Positron emission tomography (PET) is suggested for early monitoring of treatment response, assuming that effective anticancer treatment induces metabolic changes that precede morphology alterations and changes in growth. The aim of this study was to introduce multicellular tumour spheroids (MTS) to study the effect of anticancer drugs and suggest an appropriate PET tracer for further studies.
MTS of the breast cancer cell line MCF7 were exposed to doxorubicin, paclitaxel, docetaxel, tamoxifen or imatinib for 7 days for growth pattern studies and for 3 or 5 days for PET tracer studies. The effect on growth was computed using the semi-automated size determination method (SASDM). The effect on the uptake of PET tracers [18F]3'-deoxy-3'-fluorothymidine (FLT), [1-11C]acetate (ACE), [11C]choline (CHO), [11C]methionine (MET), and 2-[18F]fluoro-2-deoxyglucose (FDG) was calculated in form of uptake/viable volume of the MTS at the end of the drug exposures, and finally the uptake was related to effects on growth rate.
The drugs paclitaxel, docetaxel and doxorubicin gave severe growth inhibition, which correlated well with inhibition of the FLT uptake. FLT had, compared with ACE, CHO, MET and FDG, higher sensitivity in monitoring the therapy effects.
SASDM provides an effective, user-friendly, time-saving and accurate method to record the growth pattern of the MTS, and also to calculate the effect of the drug on PET tracer uptake. This study demonstrate the use of MTS and SASDM in combination with PET tracers as a promising approach to probe and select PET tracer for treatment monitoring of anticancer drugs and that can hopefully be applied for optimisation in breast cancer treatment.
The cytoreductive effects of anti-transferrin receptor (anti-TfnR) immunotoxins (ITs) and of ricin toxin against tumour micromasses have been evaluated in a multicellular tumour spheroid (MTS) model. More than 600 (656) MTSs obtained with human breast carcinoma (MCF7) or rat glioblastoma (9L) cell lines were treated individually with ITs or toxin and the effects induced by the treatment were measured for each MTS as volume variation vs time by applying the Gompertz growth model. Two dose-dependent patterns of MTS growth were observed in MTSs of both cell lines in response to IT or toxin treatment: (1) complete inhibition of MTS growth ('sterilisation'); and (2) partial/complete inhibition ('heterogeneous response'). Within the range of IT or toxin concentrations resulting in partial inhibition of MTS growth, the sensitivity of treated MTSs was extremely heterogeneous (the cytoreductive effects varying between 0.1 and 4 logs of cells killed for a given IT or toxin concentration). Analysis of the post-treatment regrowth kinetics indicated that treated non-sterilised and control MTSs reached the same final limiting volumes. However, the doubling time estimated for the surviving cells of treated MCF7 and 9L MTSs ranged between 15 and 50 h, indicating that each MTS had individual growing potential. In conclusion, our results indicate that at substerilising IT concentrations individual heterogenicity of MTSs may greatly influence the cytoreductive potential of ITs. An implication of our study is that the efficacy of an IT treatment in eradicating disseminated micrometastases may not be predictable a priori. The MTS model that we describe in this paper may help in dissecting out factors limiting the effect of ITs in three-dimensional tumours.
The putative tumor metastasis suppressor 1(MTSS1) is an actin-binding scaffold protein that has been implicated to play an important role in carcinogenesis and cancer metastasis, yet its role in the development of gastric cancer has not been well illustrated. In this study, we detected MTSS1 expression and explored its clinical significance in gastric cancer.
Immunohistochemistry was performed using tissue microarrays containing gastric adenocarcinoma specimens from 1,072 Chinese patients with normal adjacent mucosa, primary gastric cancer and lymph node (LN) metastasis and specific antibody against MTSS1. MTSS1 mRNA and protein expression were detected by reverse transcription-polymerase chain reaction and Western blotting. The clinical follow-up was done in the 669 patients living in Shanghai that was chose from the 1072 cases.
Complete loss of MTSS1 expression was observed in 751 cases (70.1%) of the 1,072 primary tumors and 103 (88%) of 117 nodal metastases; and loss of MTSS1 expression was significantly associated with poorly differentiated tumors, large tumor size, deep invasion level, the presence of nodal metastases and advanced disease stage. Moreover, multivariate analysis demonstrated that loss of MTSS1 expression correlated significantly with poor survival rates (RR = 0.194, 95% CI = 0.144-0.261, P < 0.001).
MTSS1 expression decreased significantly as gastric cancer progressed and metastasized, suggesting MTSS1 may serve as a useful biomarker for the prediction of outcome of gastric cancer.
Medial tibial stress syndrome (MTSS) affects 5%–35% of runners. Research over the last 40 years investigating a range of interventions has not established any clearly effective management for MTSS that is better than prolonged rest. At the present time, understanding of the risk factors and potential causative factors for MTSS is inconclusive. The purpose of this review is to evaluate studies that have investigated various risk factors and their association with the development of MTSS in runners.
Medical research databases were searched for relevant literature, using the terms “MTSS AND prevention OR risk OR prediction OR incidence”.
A systematic review of the literature identified ten papers suitable for inclusion in a meta-analysis. Measures with sufficient data for meta-analysis included dichotomous and continuous variables of body mass index (BMI), ankle dorsiflexion range of motion, navicular drop, orthotic use, foot type, previous history of MTSS, female gender, hip range of motion, and years of running experience. The following factors were found to have a statistically significant association with MTSS: increased hip external rotation in males (standard mean difference [SMD] 0.67, 95% confidence interval [CI] 0.29–1.04, P<0.001); prior use of orthotics (risk ratio [RR] 2.31, 95% CI 1.56–3.43, P<0.001); fewer years of running experience (SMD −0.74, 95% CI −1.26 to −0.23, P=0.005); female gender (RR 1.71, 95% CI 1.15–2.54, P=0.008); previous history of MTSS (RR 3.74, 95% CI 1.17–11.91, P=0.03); increased body mass index (SMD 0.24, 95% CI 0.08–0.41, P=0.003); navicular drop (SMD 0.26, 95% CI 0.02–0.50, P=0.03); and navicular drop >10 mm (RR 1.99, 95% CI 1.00–3.96, P=0.05).
Female gender, previous history of MTSS, fewer years of running experience, orthotic use, increased body mass index, increased navicular drop, and increased external rotation hip range of motion in males are all significantly associated with an increased risk of developing MTSS. Future studies should analyze males and females separately because risk factors vary by gender. A continuum model of the development of MTSS that links the identified risk factors and known processes is proposed. These data can inform both screening and countermeasures for the prevention of MTSS in runners.
medial tibial stress syndrome; injury prevention; risk factors; running injuries
In order to explore a pre-clinical method to evaluate if [18F]FDG is valid for monitoring early response, we investigated the uptake of FDG in Multicellular tumour spheroids (MTS) without and with treatment with five routinely used chemotherapy agents in breast cancer.
The response to each anticancer treatment was evaluated by measurement of the [18F]FDG uptake and viable volume of the MTSs after 2 and 3 days of treatment.
The effect of Paclitaxel and Docetaxel on [18F]FDG uptake per viable volume was more evident in BT474 (up to 55% decrease) than in MCF-7 (up to 25% decrease).
Doxorubicin reduced the [18F]FDG uptake per viable volume more noticeable in MCF-7 (25%) than in BT474 MTSs.
Tamoxifen reduced the [18F]FDG uptake per viable volume only in MCF-7 at the highest dose of 1 μM.
No effect of Imatinib was observed.
MTS was shown to be appropriate to investigate the potential of FDG-PET for early breast cancer treatment monitoring; the treatment effect can be observed before any tumour size changes occur.
The combination of PET radiotracers and image analysis in MTS provides a good model to evaluate the relationship between tumour volume and the uptake of metabolic tracer before and after chemotherapy. This feature could be used for screening and selecting PET-tracers for early assessment of treatment response.
In addition, this new method gives a possibility to assess quickly, and in vitro, a good preclinical profile of existing and newly developed anti-cancer drugs.
To report the effect of different imputation methodologies on the assessment of radiographic progression in clinical trials.
The 216-week RAPID-psoriatic arthritis (PsA) (NCT01087788) trial of certolizumab pegol (CZP) in patients with active PsA was double-blind and placebo-controlled until week 24. A primary end point was change from baseline in modified Total Sharp Score(s) (mTSS). Prespecified imputation methodology in patients with fewer than two analysable mTSS used minimum observed baseline score for missing baseline values and maximum observed week 24 score for missing week 24 values. Post hoc analyses used alternative methods of imputation in patients with fewer than two analysable mTSS. mTSS non-progressors were defined as patients with ≤0 (predefined) or ≤0.5 (post hoc) change in mTSS from baseline to week 24. Baseline mTSS and C-reactive protein levels as predictors of radiographic progression were investigated.
409 patients were randomised. Baseline demographics were similar between groups. Prespecified imputation analysis inappropriately overestimated radiographic progression (least squares mean placebo, 28.9; CZP, 18.3; p≥0.05). Multiple post hoc analyses demonstrated that CZP inhibited radiographic progression compared with placebo, particularly in patients with high baseline mTSS and C-reactive protein levels. mTSS non-progression rate was higher in CZP than placebo groups in all analyses.
Inappropriate prespecified imputation methodology resulted in an unrealistic assessment of progression in all arms. Methodologies for imputing missing radiographic data can greatly affect assessment and reporting of mTSS progression.
Anti-TNF; Psoriatic Arthritis; Outcomes research
Metastasis suppressor-1 (MTSS1) has been proposed to function as a cytoskeletal protein with a role in cancer metastasis. Recent studies have demonstrated the clinical significance of MTSS1 in certain type of cancers, yet the clinical relevance of MTSS1 in oesophageal squamous cell carcinoma (ESCC) has not been reported.
In this study, we assessed the expression levels of MTSS1 in tumours and its matched adjacent non-tumour tissues obtained from 105 ESCC patients. We also used ESCC cells with differing MTSS1 expression and assessed the influence of MTSS1 on ESCC cells.
Down-regulation of MTSS1 expression was observed both in oesophageal tumour tissues and ESCC cancer cell lines. We also reported that MTSS1 expression was associated with tumour grade (p = 0.024), lymph node metastasis (p = 0.010) and overall survival (p = 0.035). Patients with high levels of MTSS1 transcripts had a favorable prognosis in comparison with those who had reduced or absent expression levels. Using over-expression and knockdown approach, we created sublines from ESCC cells and further demonstrated that MTSS1 expression in ESCC cells significantly influenced the aggressiveness of the oesophageal cancer cells, by reducing their cellular migration and in vitro invasiveness.
MTSS1 serves as a potential prognostic indicator in human ESCC and may be an important target for cancer therapy.
metastasis suppressor-1; MTSS1; MIM; oesophageal squamous cell carcinoma; metastasis
To determine the relationship between lower extremity alignment and MTSS amongst non-professional athletes
In a prospective Study, sixty six subjects were evaluated. Bilateral navicular drop test, Q angle, Achilles angle, tibial angle, intermalleolar and intercondylar distance were measured. In addition, runner's height, body mass, history of previous running injury, running experience was recorded. Runners were followed for 17 weeks to determine occurrence of MTSS.
The overall injury rate for MTSS was 19.7%. The MTSS injury rate in girls (22%) was not significantly different from the rate in boys (14.3%). Most MTSS injuries were induced after 60 hours of exercise, which did not differ between boys and girls. There was a significant difference in right and left navicular drop (ND) in athletes with MTSS. MTSS had no significant correlation with other variables including Quadriceps, Tibia and Achilles angles, intercondylar and intermaleolar lengths and lower extremity lengths.
All measurements performed in this study were uniplanar and static. The small sample size deemed our main limitation. The accurate assessment of participants with previous history of anterior leg pain for MTSS was another limitation.
Although a significant relationship between navicular drop and MTSS was found in this study; there was not any significant relationship between lower extremity alignment and MTSS in our sample study.
miR-182 is one of the most significantly up-regulated miRNAs in hepatocellular carcinoma (HCC). Metastasis suppressor 1 (MTSS1), one target gene of miR-182, plays an important role in the metastasis of cancers. However, it remains unclear what role does function and mechanism of miR-182 and MTSS1play in HCC.
miR-182 expression was tested in 86 cases of paired HCC and normal tissues by real-time PCR and the relationships between miR-182 expression and clinicopathological parameters were analyzed. The expression of MTSS1 was evaluated by immunohistochemistry and western blot in the above tissues and its correlation with miR-182 expression was analyzed. Moreover, western blot and invasion assays were performed after transfection of pre-miR-182 or anti-miR-182 to HCC cell lines. In addition, luciferase assays was performed to confirm the regulation of miR-182 on MTSS1.
Compared with normal tissue, miR-182 was up-regulated and MTSS1 was down-regulated in HCC tissues. Moreover, the over-expression of miR-182 was correlated with intrahepatic metastasis (p = 0.034) and poor prognosis (p = 0.039) of HCC patients. There was a negative correlation between miR-182 and MTSS1 expression in both HCC tissues (r = −0.673, p < 0.01) and HCC cell lines (r = −0.931, p = 0.021). Furthermore, the up-regulation of miR-182 resulted in the down-regulation of MTSS1 and increased invasive potential of HUH-1, and reverse results were also confirmed when the expression of miR-182 was inhibited. In addition, the results of the luciferase assay demonstrated the targeted regulation of miR-182 on MTSS1.
miR-182 could promote metastasis of HCC and inhibit the expression of MTSS1. miR-182 and MTSS1 are potential prognostic markers and/or therapeutic targets in HCC.
Hepatocellular carcinoma; miR-182; Metastasis suppressor 1; Metastasis
Mtss1 encodes an actin-binding protein, dysregulated in a variety of tumors, that interacts with sonic hedgehog/Gli signaling in epidermal cells. Given the prime importance of this pathway for cerebellar development and tumorigenesis, we assessed expression of Mtss1 in the developing murine cerebellum and human medulloblastoma specimens.
During development, Mtss1 is transiently expressed in granule cells, from the time point they cease to proliferate to their synaptic integration. It is also expressed by granule cell precursor-derived medulloblastomas. In the adult CNS, Mtss1 is found exclusively in cerebellar Purkinje cells. Neuronal differentiation is accompanied by a switch in Mtss1 splicing. Whereas immature granule cells express a Mtss1 variant observed also in peripheral tissues and comprising exon 12, this exon is replaced by a CNS-specific exon, 12a, in more mature granule cells and in adult Purkinje cells. Bioinformatic analysis of Mtss1 suggests that differential exon usage may affect interaction with Fyn and Src, two tyrosine kinases previously recognized as critical for cerebellar cell migration and histogenesis. Further, this approach led to the identification of two evolutionary conserved nuclear localization sequences. These overlap with the actin filament binding site of Mtss1, and one also harbors a potential PKA and PKC phosphorylation site.
Both the pattern of expression and splicing of Mtss1 is developmentally regulated in the murine cerebellum. These findings are discussed with a view on the potential role of Mtss1 for cytoskeletal dynamics in developing and mature cerebellar neurons.
Static measures of foot posture are regularly used as part of a clinical examination to determine the need for foot level interventions. This is based on the premise that pronated and supinated foot postures may be risk factors for or associated with lower limb injury. This systematic review and meta-analysis investigates foot posture (measured statically) as a potential risk factor for lower limb overuse injuries.
A systematic search was performed using Medline, CINAHL, Embase, SportDiscus in April 2014, to identify prospective cohort studies that investigated foot posture and function as a risk factor for lower limb overuse injury. Eligible studies were classified based on the method of foot assessment: (i) static foot posture assessment; and/or (ii) dynamic foot function assessment. This review presents studies evaluating static foot posture. The methodological quality of included studies was evaluated by two independent reviewers, using an adapted version of the Epidemiological Appraisal Instrument (EAI). Where possible, effects were expressed as standardised mean differences (SMD) for continuous scaled data, and risk ratios (RR) for nominal scaled data. Meta-analysis was performed where injuries and outcomes were considered homogenous.
Twenty-one studies were included (total n = 6,228; EAI 0.8 to 1.7 out of 2.0). There was strong evidence that a pronated foot posture was a risk factor for medial tibial stress syndrome (MTSS) development and very limited evidence that a pronated foot posture was a risk factor for patellofemoral pain development, although associated effect sizes were small (0.28 to 0.33). No relationship was identified between a pronated foot posture and any other evaluated pathology (i.e. foot/ankle injury, bone stress reactions and non-specific lower limb overuse injury).
This systematic review identified strong and very limited evidence of small effect that a pronated foot posture is a risk factor for MTSS and patellofemoral pain respectively. Evaluation of static foot posture should be included in a multifactorial assessment for both MTSS and patellofemoral pain, although only as a part of the potential injury risk profile. Whilst the included measures are clinically applicable, further studies are required to determine their relationship with dynamic foot function.
Electronic supplementary material
The online version of this article (doi:10.1186/s13047-014-0055-4) contains supplementary material, which is available to authorized users.
Lower extremity; Foot; Pronation; Supination; Prospective studies; Risk factors; Musculoskeletal diseases; Review
Metastasis suppressor 1 (MTSS1) is an important tumor suppressor protein, and loss of MTSS1 expression has been observed in several types of human cancers. Importantly, decreased MTSS1 expression is associated with more aggressive forms of breast and prostate cancers, and with poor survival rate. Currently, it remains unclear how MTSS1 is regulated in cancer cells, and whether reduced MTSS1 expression contributes to elevated cancer cell proliferation and migration. Here we report that the SCFβ-TRCP regulates MTSS1 protein stability by targeting it for ubiquitination and subsequent destruction via the 26S proteasome. Notably, depletion of either Cullin 1 or β-TRCP1 led to increased levels of MTSS1. We further demonstrated a crucial role for Ser322 in the DSGXXS degron of MTSS1 in governing SCFβ-TRCP-mediated MTSS1 degradation. Mechanistically, we defined that Casein Kinase Iδ (CKIδ) phosphorylates Ser322 to trigger MTSS1's interaction with β-TRCP for subsequent ubiquitination and degradation. Importantly, introducing wild-type MTSS1 or a non-degradable MTSS1 (S322A) into breast or prostate cancer cells with low MTSS1 expression significantly inhibited cellular proliferation and migration. Moreover, S322A-MTSS1 exhibited stronger effects in inhibiting cell proliferation and migration when compared to ectopic expression of wild-type MTSS1. Therefore, our study provides a novel molecular mechanism for the negative regulation of MTSS1 by β-TRCP in cancer cells. It further suggests that preventing MTSS1 degradation could be a possible novel strategy for clinical treatment of more aggressive breast and prostate cancers.
tumor suppressor; MTSS1; ubiquitination; phosphorylation; migration
In women with breast cancer submitted to neoadjuvant chemotherapy based in doxorubicin, tumor expression of groups of three genes (PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2) have classified them as responsive or resistant. We have investigated whether expression of these trios of genes could predict mammary carcinoma response in dogs and whether tumor slices, which maintain epithelial-mesenchymal interactions, could be used to evaluate drug response in vitro.
Tumors from 38 dogs were sliced and cultured with or without doxorubicin 1 μM for 24 h. Tumor cells were counted by two observers to establish a percentage variation in cell number, between slices. Based on these results, a reduction in cell number between treated and control samples ≥ 21.7%, arbitrarily classified samples, as drug responsive. Tumor expression of PRSS11, MTSS1, CLPTM1 and SMYD2, was evaluated by real time PCR. Relative expression results were then transformed to their natural logarithm values, which were spatially disposed according to the expression of trios of genes, comprising PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2. Fisher linear discrimination test was used to generate a separation plane between responsive and non-responsive tumors.
Culture of tumor slices for 24 h was feasible. Nine samples were considered responsive and 29 non-responsive to doxorubicin, considering the pre-established cut-off value of cell number reduction ≥ 21.7%, between doxorubicin treated and control samples. Relative gene expression was evaluated and tumor samples were then spatially distributed according to the expression of the trios of genes: PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2. A separation plane was generated. However, no clear separation between responsive and non-responsive samples could be observed.
Three-dimensional distribution of samples according to the expression of the trios of genes PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2 could not predict doxorubicin in vitro responsiveness. Short term culture of mammary gland cancer slices may be an interesting model to evaluate chemotherapy activity.
Mtss1 is located within chromosomal region 8q23-24, which is one of the three most commonly amplified regions in HNSCC. Mtss1 is lost in metastatic cells but confusingly is commonly overexpressed in primary tumors. Here we address possible reasons why Mtss1 is positively selected for in primary tumors. We find that Mtss1 enhances the localization of the EGF receptor to the plasma membrane, prolonging EGF signaling and resulting in enhanced proliferation in HNSCC. Depletion of Mtss1 results in decreased EGF receptor levels and decreased phosphorylation of Erk1/2 and Akt. However, when cells are at high density and adherent to each other, analogous to conditions in a solid tumor, Mtss1 does not confer any growth advantage, either in basal conditions or following EGF stimulation. This could indicate why Mtss1 might be lost in metastases, but preserved in early primary tumors. This is supported by an organotypic assay showing that Mtss1 expressing cells display a less proliferative more epithelial-like morphology on top of a collagen matrix. Furthermore, xenograft tumors expressing Mtss1 initially grow more rapidly, but later show less proliferation and more differentiation. Mtss1 positively modulates EGF signaling at low cell densities to promote proliferation and, therefore, may be beneficial for the early stages of primary HNSCC tumor growth. However, at high cell densities, Mtss1 impacts negatively on EGF signaling and this suggests why it inhibits metastasis.
Mtss1; HNSCC; epidermal growth factor receptor
Thacker SB, Gilchrist J, Stroup DF, Kimsey CD. The prevention of shin splints in sports: a systematic review of literature. Med Sci Sports Exerc. 2002;34(1):32–40.
Among physically active individuals, which medial tibial stress syndrome (MTSS) prevention methods are most effective to decrease injury rates?
Studies were identified by searching MEDLINE (1966–2000), Current Contents (1996–2000), Biomedical Collection (1993–1999), and Dissertation Abstracts. Reference lists of identified studies were searched manually until no further studies were identified. Experts in the field were contacted, including first authors of randomized controlled trials addressing prevention of MTSS. The Cochrane Collaboration (early stage of Cochrane Database of Systematic Reviews) was contacted.
Inclusion criteria included randomized controlled trials or clinical trials comparing different MTSS prevention methods with control groups. Excluded were studies that did not provide primary research data or that addressed treatment and rehabilitation rather than prevention of incident MTSS.
A total of 199 citations were identified. Of these, 4 studies compared prevention methods for MTSS. Three reviewers independently scored the 4 studies. Reviewers were blinded to the authors' names and affiliations but not the results. Each study was evaluated independently for methodologic quality using a 100-point checklist. Final scores were averages of the 3 reviewers' scores.
Prevention methods studied were shock-absorbent insoles, foam heel pads, Achilles tendon stretching, footwear, and graduated running programs. No statistically significant results were noted for any of the prevention methods. Median quality scores ranged from 29 to 47, revealing flaws in design, control for bias, and statistical methods.
No current evidence supports any single prevention method for MTSS. The most promising outcomes support the use of shock-absorbing insoles. Well-designed and controlled trials are critically needed to decrease the incidence of this common injury.
shin splints; injury prevention methods; stress injuries; running injuries; tibial injuries
Previous studies have suggested that metastasis tumour suppressor-1 (MTSS1) plays a key role in cancer metastasis. Firstly, in this study we assessed MTSS1 expression levels in prostate cancer cell lines to reveal any changes in cell properties. Secondly, we aimed to clarify the cellular function of MTSS1 in prostate cancer cells. MTSS1 expression levels were assessed in different types of cancer cell lines through the RT-PCR analysis technique. The influence of MTSS1 was further examined via biological overexpression and knockdown in the prostate cancer cell lines. Two prostate cell lines were chosen for either knockdown or overexpression of the MTSS1 gene. The overexpression of MTSS1 in PC-3 human prostate cancer cells significantly suppressed the migratory, growth and adherence properties of the cells (p<0.01). By contrast, the knockdown of MTSS1 in DU-145 human prostate cancer cells dramatically enhanced these properties (p<0.001). We concluded that MTSS1 demonstrates the ability to play a role in controlling the metastatic nature of prostate cancer cells.
metastasis tumour suppressor-1; ribozyme transgenes; cell growth; cell migration; prostate cancer
In the IMAGE study, rituximab plus methotrexate (MTX) inhibited joint damage and improved clinical outcomes at 1 year in MTX-naïve patients with early active rheumatoid arthritis.
The aim of this study was to assess joint damage progression and clinical outcomes over 2 years.
Patients (n=755) were randomised to receive rituximab 2×500 mg+MTX, 2×1000 mg+MTX or placebo+MTX. The placebo-controlled period continued to week 104. Two-year end points were defined as secondary or exploratory and included change in total Genant-modified Sharp score (mTSS), total erosion score and joint space narrowing score from baseline to week 104. Clinical efficacy and physical function end points were also assessed.
At 2 years, rituximab 2×1000 mg+MTX maintained inhibition of progressive joint damage versus MTX alone (mTSS change 0.41 vs 1.95; p<0.0001 (79% inhibition)), and a higher proportion of patients receiving rituximab 2×1000 mg+MTX had no radiographic progression over 2 years compared with those receiving MTX alone (57% vs 37%; p<0.0001). Contrary to 1-year results, exploratory analysis of rituximab 2×500 mg+MTX at 2 years showed that progressive joint damage was slowed by ∼61% versus placebo+MTX (mTSS, exploratory p=0.0041). Improvements in clinical signs and symptoms and physical function seen after 1 year in rituximab-treated patients versus those receiving placebo were maintained at year 2. Safety profiles were similar between groups.
Treatment with rituximab 2×1000 mg+MTX was associated with sustained improvements in radiographic, clinical and functional outcomes over 2 years.
Clinical trials.gov identifier NCT00299104.
Necrosis is commonly found in the core region of solid tumours due to metabolic stress such as hypoxia and glucose deprivation (GD) resulting from insufficient vascularization. Necrosis promotes tumour growth and development by releasing the tumour-promoting cytokine high mobility group box 1 (HMGB1); however, the molecular mechanism underlying necrotic cell death remains largely unknown. In this study, we show that early growth response 1 (Egr-1) is induced in a reactive oxygen species (ROS)-dependent manner by GD in several cell lines such as A549, MDA-MB-231 and HepG2 cells that exhibit necrosis upon GD. We found that Egr-1 short hairpin RNA (shRNA) prevented GD-induced necrosis and HMGB1 release. Necrosis-inhibiting activity of Egr-1 shRNA was also seen in multicellular tumour spheroids (MTSs), an in vitro tumour model system. In contrast, Egr-1 overexpression appeared to make tumour cells more susceptible to GD-induced necrosis. Finally, Egr-1 shRNA suppressed the growth of MTSs. These findings demonstrate that Egr-1 is implicated in GD-induced necrosis and tumour progression.
early growth response 1; glucose deprivation; reactive oxygen species; necrosis; multicellular tumour spheroids
Neuroendocrine tumors (NETs) are rare tumors, with an incidence of two per 100, 000 individuals per year, and they account for 0.5% of all human malignancies.1 Other than surgery for the minority of patients who present with localized disease, there is little or no survival benefit of systemic therapy. Therefore, there is a great need to better understand the biology of NETs, and in particular define new therapeutic targets for patients with nonresectable or metastatic neuroendocrine tumors. 3D cell culture is becoming a popular method for drug screening due to its relevance in modeling the in vivo tumor tissue organization and microenvironment.2,3 The 3D multicellular spheroids could provide valuable information in a more timely and less expensive manner than directly proceeding from 2D cell culture experiments to animal (murine) models.
To facilitate the discovery of new therapeutics for NET patients, we have developed an in vitro 3D multicellular spheroids model using the human NET cell lines. The NET cells are plated in a non-adhesive agarose-coated 24-well plate and incubated under physiological conditions (5% CO2, 37 °C) with a very slow agitation for 16-24 hr after plating. The cells form multicellular spheroids starting on the 3rd or 4th day. The spheroids become more spherical by the 6th day, at which point the drug treatments are initiated. The efficacy of the drug treatments on the NET spheroids is monitored based on the morphology, shape and size of the spheroids with a phase-contrast light microscope. The size of the spheroids is estimated automatically using a custom-developed MATLAB program based on an active contour algorithm. Further, we demonstrate a simple method to process the HistoGel embedding on these 3D spheroids, allowing the use of standard histological and immunohistochemical techniques.
This is the first report on generating 3D spheroids using NET cell lines to examine the effect of therapeutic drugs. We have also performed histology on these 3D spheroids, and displayed an example of a single drug's effect on growth and proliferation of the NET spheroids. Our results support that the NET spheroids are valuable for further studies of NET biology and drug development.
Cancer Biology; Issue 66; Medicine; Neuroscience; Cell Culture; Tissue Engineering; 3D model; multicellular spheroids; therapeutic drugs; neuroendocrine tumor cell lines; agarose overlay platform; paraffin embedding
Evidences of biologics-free disease control after discontinuing adalimumab (ADA) in rheumatoid arthritis (RA) patients in clinical practice have not been sufficiently investigated. Purpose of this study is to investigate whether disease activity score 28 (DAS28)- erythrocyte sedimentation rate (ESR) remission was preserved after discontinuation of ADA in patients with RA.
This is an observational but not a randomized controlled study. Among 197 RA patients who initiated with combination of ADA with concomitant MTX, 69 (35%) acquired DAS28 (ESR) < 2.6 for at least 24 weeks. Of those 69 patients, 51 went on ADA discontinuation with their consent, and finally 50 of those with follow-up of > 24 weeks were evaluated. The effect of discontinuing ADA on clinical disease activity, functional disability and radiographic progression were evaluated by DAS28 (ESR), the clinical disease activity index (CDAI) and the simplified disease activity index (SDAI), by a health assessment questionnaire-disability index (HAQ-DI) and by the modified total Sharp score (mTSS), respectively.
The mean age of the participants was 59.5 years with the mean disease duration of 7.1 years. Out of the 50 patients, 29 (58%) were maintained in DAS28 (ESR) < 2.6 at 24 weeks after discontinuing ADA. A logistic regression analysis showed that DAS28 (ESR) at baseline significantly predicted a DAS28 (ESR) < 2.6 maintained after discontinuation of ADA, and a receiver-operating characteristic (ROC) analysis showed that the cut-off value of DAS28 (ESR) at discontinuation was 2.16. The mean HAQ-DI at six months after discontinuing ADA was 0.1 in patients who kept in DAS28 (ESR) < 2.6, and 94.9% (37/39) showed no evidence of radiographic progression (> 0.5 per year of a change in mTSS) at 1 year.
It was possible to maintain DAS28 (ESR) < 2.6 after discontinuation of ADA without functional and radiographic progression and very low DAS28 (ESR) at the discontinuation was associated with successful ADA-free DAS28 (ESR) < 2.6 in patients with RA.
University Hospital Medical Information Network Identifier: UMIN000006669.
To evaluate the long-term effectiveness and tolerability of adalimumab in the treatment of psoriatic arthritis (PsA).
Patients with PsA who completed a 24-week, double-blind study of adalimumab versus placebo were eligible to enroll in an open-label extension study and receive adalimumab 40 mg subcutaneously every other week for up to an additional 120 weeks. At the time of this analysis, available efficacy evaluations throughout 2 years of treatment (n = 245) included American College of Rheumatology (ACR) 20%, 50% and 70% improvement scores, measures of joint disease and skin disease, disability and quality of life; modified total Sharp scores (mTSS) were available for 2.75 years of treatment for patients who received adalimumab in the 24-week study.
After 24 weeks of double-blind treatment, the mean change in mTSS was −0.2 for the adalimumab group (N = 144) and 1.0 for the placebo group (N = 152; p<0.001), and outcomes for all individual ACR component variables were significantly improved in adalimumab compared with placebo-treated patients. Compared with 24-week responses, inhibition of radiographic progression and improvements in joint disease were maintained in most patients during long-term, open-label adalimumab treatment. Also, improvements in skin disease were maintained, with >20% of patients achieving the strict criterion of psoriasis area and severity index 100. The nature and frequency of adverse events during long-term adalimumab treatment were consistent with the safety profile during short-term treatment.
The clinical and radiographic efficacy of adalimumab demonstrated during short-term treatment was sustained during long-term treatment. Adalimumab has a favourable risk–benefit profile in patients with PsA.
Trial registration number:
Glandular epithelial cells differentiate into complex multicellular or acinar structures, when embedded in three-dimensional (3D) extracellular matrix. The spectrum of different multicellular morphologies formed in 3D is a sensitive indicator for the differentiation potential of normal, non-transformed cells compared to different stages of malignant progression. In addition, single cells or cell aggregates may actively invade the matrix, utilizing epithelial, mesenchymal or mixed modes of motility. Dynamic phenotypic changes involved in 3D tumor cell invasion are sensitive to specific small-molecule inhibitors that target the actin cytoskeleton. We have used a panel of inhibitors to demonstrate the power of automated image analysis as a phenotypic or morphometric readout in cell-based assays. We introduce a streamlined stand-alone software solution that supports large-scale high-content screens, based on complex and organotypic cultures. AMIDA (Automated Morphometric Image Data Analysis) allows quantitative measurements of large numbers of images and structures, with a multitude of different spheroid shapes, sizes, and textures. AMIDA supports an automated workflow, and can be combined with quality control and statistical tools for data interpretation and visualization. We have used a representative panel of 12 prostate and breast cancer lines that display a broad spectrum of different spheroid morphologies and modes of invasion, challenged by a library of 19 direct or indirect modulators of the actin cytoskeleton which induce systematic changes in spheroid morphology and differentiation versus invasion. These results were independently validated by 2D proliferation, apoptosis and cell motility assays. We identified three drugs that primarily attenuated the invasion and formation of invasive processes in 3D, without affecting proliferation or apoptosis. Two of these compounds block Rac signalling, one affects cellular cAMP/cGMP accumulation. Our approach supports the growing needs for user-friendly, straightforward solutions that facilitate large-scale, cell-based 3D assays in basic research, drug discovery, and target validation.
Mitochondrial processing peptidase (MPP) consists of α and β subunits that catalyze the cleavage of N-terminal mitochondrial-targeting sequences (N-MTSs) and deliver preproteins to the mitochondria. In plants, both MPP subunits are associated with the respiratory complex bc1, which has been proposed to represent an ancestral form. Subsequent duplication of MPP subunits resulted in separate sets of genes encoding soluble MPP in the matrix and core proteins (cp1 and cp2) of the membrane-embedded bc1 complex. As only α-MPP was duplicated in Neurospora, its single β–MPP functions in both MPP and bc1 complexes. Herein, we investigated the MPP/core protein family and N-MTSs in the kinetoplastid Trypanosoma brucei, which is often considered one of the most ancient eukaryotes. Analysis of N-MTSs predicted in 336 mitochondrial proteins showed that trypanosomal N-MTSs were comparable with N-MTSs from other organisms. N-MTS cleavage is mediated by a standard heterodimeric MPP, which is present in the matrix of procyclic and bloodstream trypanosomes, and its expression is essential for the parasite. Distinct Genes encode cp1 and cp2, and in the bloodstream forms the expression of cp1 is downregulated along with the bc1 complex. Phylogenetic analysis revealed that all eukaryotic lineages include members with a Neurospora-type MPP/core protein family, whereas cp1 evolved independently in metazoans, some fungi and kinetoplastids. Evolution of cp1 allowed the independent regulation of respiration and protein import, which is essential for the procyclic and bloodstream forms of T. brucei. These results indicate that T. brucei possesses a highly derived MPP/core protein family that likely evolved in response to its complex life cycle and does not appear to have an ancient character proposed earlier for this eukaryote.
mitochondrial processing peptidase; bc1 complex; mitochondrial targeting sequence; trypanosome; evolution
This study aimed to investigate the expression of metastasis suppressor 1 (MTSS1) in cervical intraepithelial neoplasia (CIN) and malignant cervical tissues, and the role of MTSS1 in carcinogenesis. MTSS1 expression was detected by immunohistochemistry in 147 cervical tissue specimens collected from 30 healthy individuals, 30 patients with cervical CIN I, 30 patients with CIN II–III and 57 patients with cervical cancer. The association between MTSS1 expression and clinicopathological factors was also examined. MTSS1 was found to be positively expressed in 43.33% CIN I cervical tissues, 100% CIN II–III cervical tissues and 100% malignant cervical tissues, but was weakly or negatively expressed in benign cervical tissues. The positive expression rates of MTSS1 were significantly higher in CIN II–III and malignant cervical tissues than in CIN I or normal cervical tissues (P<0.05). When examining MTSS1 expression and clinicopathological factors, the strong positive MTSS1 expression rates in early-stage versus middle- and advanced-stage cervical cancer tissues were 39.13% and 82.35%, respectively. Furthermore, the positive expression rates of MTSS1 were significantly higher in cervical tissues at an advanced clinical stage than those at an early clinical stage (P<0.05). The results suggest that the dysregulation of MTSS1 may be involved in cervical carcinogenesis, and thus MTSS1 may be a novel diagnostic biomarker or therapeutic target in cervical cancer patients.
cervical malignancy; cervical intraepithelial neoplasia; metastasis suppressor 1
Multicellular spheroids, an appropriate in vitro system for simulating 3-D tumor micro-milieu can be used for evaluating and predicting tumor response to therapeutic agents including metabolic inhibitors. However, detailed understanding of the nature, distribution and sensitivity/responses of cellular sub-populations to potential therapeutic agents/strategies is required for using this unique model with optimal precision. Spheroid characteristics may also vary considerably with the origin and type of cell line used, and thorough characterization of viable and dissociated glioma cell spheroids is not yet completely known. In order to evaluate in vivo responses of gliomas to various therapeutic strategies, especially the metabolic inhibitors capable of penetrating the blood brain barrier, we have characterized continuously growing spheroids of a human glioma cell line (BMG-1) with respect to organization, growth, viability, cell survival, cell death, metabolic and mitochondrial status, oxidative stress and radiation response using microscopy, flow cytometry and enzymatic assays. Spheroids were fed daily with fresh medium in order to maintain nutrient supply to outer cellular layers while hypoxia/necrosis developed in the innermost cells of enlarging spheroids.
Volume of spheroids, fed daily with fresh medium, increased exponentially during 7–28 days of growth through three population doublings. Proportion of G1-phase cells was higher (~60%) than exponentially growing monolayer cells (~48%). A significant fraction of S-phase cells turned metabolically inactive (disengaged in DNA synthesis) with increasing age of the spheroids, unlike in quiescent monolayer cultures, where the fraction of S-phase cells was less than 5%. With increasing spheroid size, increasing sub-populations of cells became non-viable and entered apoptosis or necrosis revealed by Annexin-V-FITC/PI staining. PI positive (necrotic) cells were not confined to the centre of the spheroid, but distributed at certain discrete foci. Average glucose consumption and lactate production were 2–3 folds higher in viable spheroid cells compared to monolayer cells, implying a compensatory increase in glycolysis possibly due to hypoxic environment. HIF-1α was expressed only in spheroids and increased in an age-dependent manner, whereas c-Myc (known to induce apoptosis in glucose-deprived cells) levels were three times higher than monolayer cells. Mitochondrial mass and activity decreased significantly during first 14 days of growth but increased with age, and were not associated with increase in ROS levels. Bcl-2 and Bax levels were higher (~2 folds) than monolayers, while the ratio (Bcl/Bax) remained unaltered. Radiation-induced oxidative stress was considerably less in spheroids as compared to monolayers, and corresponded well with increase in radioresistance demonstrated by the clonogenic assay, similar to hypoxia induced radioresistance observed in tumors.
Development of S-negative cells and reduced endogenous and radiation-induced ROS coupled with higher levels of anti (Bcl2) as well as pro (Bax) apoptotic regulators observed in spheroids suggest the intricate/complex nature of endogenous as well as induced stress resistance that could exist in tumors, which contribute to the treatment resistance.