Epidermal growth factor receptor (EGFR) mutation is strongly associated with the therapeutic effect of tyrosine kinase inhibitors (TKIs) in patients with non-small-cell lung cancer (NSCLC). Nevertheless, tumor tissue that needed for mutation analysis is frequently unavailable. Body fluid was considered to be a feasible substitute for the analysis, but arising problems in clinical practice such as relatively lower mutation rate and poor clinical correlation are not yet fully resolved.
In this study, 50 patients (32 pleural fluids and 18 plasmas) with TKIs therapy experience and with direct sequencing results were selected from 220 patients for further analysis. The EGFR mutation status was re-evaluated by Amplification Refractory Mutation System (ARMS), and the clinical outcomes of TKIs were analyzed retrospectively.
As compared with direct sequencing, 16 positive and 23 negative patients were confirmed by ARMS, and the other 11 former negative patients (6 pleural fluids and 5 plasmas) were redefined as positive, with a fairly well clinical outcome (7 PR, 3 SD, and 1 PD). The objective response rate (ORR) of positive patients was significant, 81.3% (direct sequencing) and 72.7% (ARMS) for pleural fluids, and 80% (ARMS) for plasma. Notably, even reclassified by ARMS, the ORR for negative patients was still relatively high, 60% for pleural fluids and 46.2% for plasma.
When using body fluids for EGFR mutation analysis, positive result is consistently a good indicator for TKIs therapy, and the predictive effect was no less than that of tumor tissue, no matter what method was employed. However, even reclassified by ARMS, the correlation between negative results and clinical outcome of TKIs was still unsatisfied. The results indicated that false negative mutation still existed, which may be settled by using method with sensitivity to single DNA molecule or by optimizing the extraction procedure with RNA or CTC to ensure adequate amount of tumor-derived nucleic acid for the test.
Body Fluids; EGFR Mutation; Direct Sequencing; ARMS; TKIs; NSCLC
Esophageal squamous cell carcinoma (ESCC) is an aggressive tumor with dismal prognosis and high incidence and mortality in Kazakh population. MiR-34a, a direct p53 target gene, possesses tumor-suppressive properties as they mediate apoptosis, cell cycle arrest, and senescence. The reduced expression of miR-34a by methylation in various cancers has been reported.
To determine whether aberrant miR-34a methylation occurs in esophageal cancer, the DNA methylation of 23 CpGs sites in the miR-34a promoter was quantitatively analyzed in relation to the translation initiation site by MALDI -TOF mass spectrometry in 59 ESCC tissues and 34 normal tissues from the Kazakh population. Real-time PCR was used to detect the inhibition of miR-34a expression levels and to evaluate their association with methylation.
We found that miR-34a is more frequently methylated in ESCC (0.133 ± 0.040) than in controls (0.066 ± 0.045, P < 0.01). A nearly two-fold increase in miR-34a expression for the hypomethylated promoter was found in normal esophageal tissues than ESCC with hypermethylation (P <0.0001), pointing to a negative relationship between miR-34a CpG sites methylation and expression(r = −0.594, P = 0.042). The hypermethylation of miR-34a CpG_8.9 was associated with the advanced UICC stage III/IV of the esophageal cancers, and the hypermethylation of CpG_8.9 and CpG_5 of miR-34a was significantly correlated with lymph node metastasis.
Our findings suggest that miR-34a is involved in the etiology of ESCC and that hypermethylated miR-34a is a potential biomarker for ESCC diagnosis and prognosis. Moreover, targeting miR-34a methylation by demethylating agents may offer a novel strategy for anticancer therapy of ESCC.
MiR-34a; Esophageal squamous cell carcinoma; Kazakh; Methylation
This study investigates the expression of Lewis y antigen, integrin αv, β3 in epithelial ovarian cancer tissues. We further evaluate the relationship between their expression and chemotherapy resistance of ovarian cancer and its possible clinical significance.
Tissues of 92 patients with ovarian cancer meeting the inclusion criteria with complete follow-up data were enrolled and divided into chemotherapy resistant group and sensitive group. The expression and relationship of Lewis y antigen and integrin αv, β3 are assessed in paraffin sections using immunohistochemistry and double-labeling immunofluorescence method. Multivariate logistic regression analysis was used to investigate the relationship between age, clinical stage, differentiation, histologic subtype, Lewis y antigen and integrin αv, β3 expression in ovarian cancer patients.
The expression rates of Lewis y antigen and integrin αv in the resistant group, significantly higher than the rates found in the sensitive group (p <0.05). Multivariate analysis showed that the expression of Lewis y antigen, integrin αv and ovarian cancer’s clinical stage were independent, drug resistance-related risk factors. The expression levels of Lewis y antigen and integrin αv, β3 were positively correlated with each other.
A close correlation between Lewis y antigen, integrin αv, β3 and ovarian cancer was observed. Lewis y antigen can influence the biological behavior of a tumor cell as an important composition of integrin αv, β3 by some signal pathway. And the expression of Lewis y antigen, integrin αv and ovarian cancer’s clinical stage are both independent, drug resistance-related risk factors.
Ovarian Cancer; Lewis y Antigen; Integrin αv, β3; Chemotherapeutic Drug Resistance
The tumor suppressor gene CDKN2A generates at least three different transcriptional variants, each of which is thought to encode a tumor suppressor. However, the inhibitory activities of these variants have not yet been compared in the same cells. Protein therapy is known to have several advantages over gene therapy. Thus, investigation of the exogenous protein molecule of the most effective suppressor may yield meaningful information regarding protein-based cancer therapy.
The inhibitory effects of p16INK4a, p14ARF and p12 were studied in the human lung cancer cell line A549 which lacks the CDKN2A locus. The eukaryotic expression plasmids of the three transcriptional variants were constructed and stably transfected into the cells. RNA and protein expression by the plasmids was confirmed using RT-PCR and fluorescence immunocytochemistry, respectively. Cell growth inhibition and cell-cycle redistribution after transfection were investigated based on growth curve and flow cytometry analyses. An exogenous His-tag fusion p16INK4a protein was obtained and purified by affinity chromatography. Cell growth inhibition and cell cycle arrest induced by the expression of p16INK4a protein were measured in A549 cells transduced with the exogenous protein.
While all three variants suppressed cell growth, p16INK4a had the strongest effect. Marked G1-phase accumulation and S-phase inhibition were induced by p16INK4a and p14ARF but not by p12. Exogenous p16INK4a protein was successfully expressed and purified and transduction of the fusion protein into A549 cells inhibited cell growth by G1→S arrest.
Among the three transcript variants, p16INK4a has a greater inhibitory effect than p14ARF and p12; exogenous p16INK4a protein should be further investigated for use in cancer therapy as a protein agent.
Interleukin-10(IL-10) is a multifunctional cytokine with both immunosuppressive and antiangiogenic functions. Polymorphisms in the IL-10 gene promoter genetically determine interindividual differences in IL-10 production. This study was performed to determined whether polymorphisms in the IL-10 gene promoter were associated with breast cancer in a Chinese Han population.
We genotyped 315 patients with breast cancer and 322 healthy control subjects for -1082A/G, -819T/C and -592A/C single nucleotide polymorphisms in the promoter region of the IL-10 gene by polymerase chain reactionerestriction fragment length polymorphism (PCR-RFLP).
There were no significant differences in genotype, allele, or haplotype frequencies in all three loci between patients and healthy controls. Analysis of breast cancer prognostic and predictive factors revealed that the -1082AA genotype was associated with a significantly increased risk of lymph node (LN) involvement (P = 0.041) and larger tumor size (P = 0.039) at the time of diagnosis. Furthermore, in the haplotype analysis of IL-10 gene, we found that patients carrying ATA haplotype were in higher LN involvement (p = 0.022) and higher tumor stage(p = 0.028) of breast cancer at the time of diagnosis compared with others.
Our findings suggest that IL-10 promoter polymorphisms participate in the progression of breast cancer rather than in its initial development in Chinese Han women.
Genetic factors are thought to play a role in development for colorectal carcinogenesis. ICAM-1 is a polymorphic gene, thus, the present study investigated the relationship between the polymorphisms of ICAM-1 and the susceptibility and phenotypical characteristics of colorectal cancer (CRC).
The polymorphisms at ICAM-1 exon 4 (G241R) and exon 6 (E469K) were detected by PCR with sequence-specific primers. The relationship between specific genotypes of ICAM-1 and differentiation of CRC was evaluated by the histological grade.
We showed only GG genotype of ICAM-1 individuals in either CRC or normal controls. The KK genotype of ICAM-1 K469E was found more frequently than in the controls (P < 0.05). Patients with well-differentiated CRC displayed the KK more frequently than those of poor differentiation (P < 0.05).
The findings indicate that polymorphisms of G241R are rare in Chinese population and that KK genotype of ICAM-1 K469E is significantly associated with well differentiation of CRC.
The sustained growth of tumors necessitates neovascularization. As one of the potent endogenous vascular inhibitors, endostatin has been widely used in antiangiogenesis therapy for tumor. Cisplatin is normally administered in chemotherapy for lung cancer but accompanied with serious side effects. In the current study, we investigated a novel chemo-antiangiogenesis therapeutic strategy to both improve toxic effects on lung cancer cells and reduce damages to normal cells in the anti-tumor therapy.
In vitro, we transduced LLC cells with Ad-hEndo and collected supernatants. Western blotting analysis of the supernatants revealed expression of endostatin. In vivo, to fully investigate the suppression effect on murine lung cancer of the combination therapy, we injected recombinant human endostatin adenovirus intratumorally plus a low dose of cisplatin intraperitoneally routinely. The tumor volume and survival time were observed. Angiogenesis was apparently inhibited within the tumor tissues and on the alginate beads. Assessment of apoptotic cells by the TUNEL assay was conducted in the tumor tissues.
The combination treatment significantly suppressed the tumor growth and prolonged survival time of the murine LLC tumor model. This anti-tumor activity was associated with decreased microvessel density and increased apoptotic index of tumor cells.
According to the results in this study, recombinant human endostatin adenovirus in combination with a low dose of cisplatin demonstrated apparent synergistic anti-tumor activity without marked toxicity. Thus, these observations may provide a rational alternative for lung cancer treatment.
Colorectal cancer is the third most commonly diagnosed cancer worldwide. Although surgery remains the best treatment for this disease, adjuvant chemotherapy and radiotherapy are also very important in clinical practice. However, the notorious refractory lack of responses to radiochemotherapy greatly limits the application of radiochemotherapy in the context of colorectal cancer.
There is a growing interest in the role that Aurora B may play in colorectal cancer cell survival as well as other cancer subtypes. In the current study, we sought to ascertain whether blocking of Aurora B signaling machinery by a small molecule inhibitor, CCT137690, could synergize radiation-induced colorectal cancer cell death. Results showed that CCT137690 increases the sensitivity of SW620 cells to radiation. Mechanistic studies revealed that Aurora B-Survivin pathway may be involved in this synergistic effect.
Taken together, our results for the first time show that Aurora B inhibition and radiation exert a synergistic effect, resulting in enhanced colorectal cancer cell death. This synergistic effect is clinically relevant as lower doses of radiation could be used for cancer treatment, and could provide significant clinical benefits in terms of colorectal cancer management, while reducing unwanted side-effects.
CCT137690; Aurora B; Radiotherapy; Colorectal cancer
Here we aimed to investigate the effect of COX-2 siRNA on proliferation and angiogenesis of gastric cancer cells.
The gastric cancer cell line SGC7901 was transfected with COX-2 siRNA, then the growth and angiogenesis of cells were detected by in vitro and in vivo assay. Human microarray, RT-PCR and western blot were used to identify differentially expressed angiogenesis-related molecules in cells with decreased expression of COX-2.
Down-regulation of COX-2 could significantly inhibit the in vitro and in vivo growth of gastric cancer cells, and suppress the migration and tube formation of human umbilical vein endothelial cells. Totally 23 angiogenesis-related molecules were found involved in COX-2-induced angiogenesis suppression. The results of RT-PCR and western blot showed that down-regulation of COX-2 might inhibit VEGF, Flt-1, Flk-1/KDR, angiopoietin-1, tie-2, MMP2 and OPN.
COX-2 might mediate tumor angiogenesis and growth, and could be considered as a target for gastric cancer therapy.
The purpose of the study was to explore the anti-tumor effect of ultrasound -targeted microbubble destruction mediated herpes simplex virus thymidine kinase (HSV-TK) suicide gene system on mice hepatoma.
Forty mice were randomly divided into four groups after the models of subcutaneous transplantation tumors were estabilished: (1) PBS; (2) HSV-TK (3) HSV-TK+ ultrasound (HSV-TK+US); (4) HSV-TK+ultrasound+microbubbles (HSV-TK+US+MB). The TK protein expression in liver cancer was detected by western-blot. Applying TUNEL staining detected tumor cell apoptosis. At last, the inhibition rates and survival time of the animals were compared among all groups.
The TK protein expression of HSV-TK+MB+US group in tumor-bearing mice tissues were significantly higher than those in other groups. The tumor inhibitory effect of ultrasound-targeted microbubble destruction mediated HSV-TK on mice transplantable tumor was significantly higher than those in other groups (p < 0.05), and can significantly improve the survival time of tumor-bearing mice.
Ultrasound-targeted microbubble destruction can effectively transfect HSV-TK gene into target tissues and play a significant inhibition effect on tumors, which provides a new strategy for gene therapy in liver cancer.
HBO1 (histone acetyltransferase binding to ORC1) is a histone acetyltransferase (HAT) which could exert oncogenic function in breast cancer. However, the biological role and underlying mechanism of HBO1 in breast cancer remains largely unknown. In the current study, we aimed to investigate the role of HBO1 in breast cancer and uncover the underlying molecular mechanism.
Immunohistochemistry was applied to detect HBO1 protein expression in breast cancer specimens (n = 112). The expression of protein level was scored by integral optical density (IOD) for further statistical analyses using SPSS. Real-time PCR was used to simultaneously measure mRNA levels of HBO1. The HBO1 protein expression in breast cancer cells was confirmed by western blot.
HBO1 was highly expressed in breast cancer tissues and significantly correlated with estrogen receptor α (ERα) (p < 0.001) and progestational hormone (PR) (p = 0.002). HBO1 protein level also correlated positively with histology grade in ERα positive tumors (p = 0.016) rather than ERα negative tumors. 17β-estradiol (E2) could upregulate HBO1 gene expression which was significantly inhibited by ICI 182,780 or ERα RNAi. E2-increased HBO1 protein expression was significantly suppressed by treatment with inhibitor of MEK1/2 (U0126) in T47 D and MCF-7 cells.
HBO1 was an important downstream molecule of ERα, and ERK1/2 signaling pathway may involved in the expression of HBO1 increased by E2.
Secreted protein acidic and rich in cysteine (SPARC) plays a key role in the development of many tissues and organ types. Aberrant SPARC expression was found in a wide variety of human cancers, contributes to tumor development. Because SPARC was found to be overexpressed in human gastric cancer tissue, we therefore to explore the expression of SPARC in gastric cancer lines and the carcinogenic mechanisms.
SPARC expression was evaluated in a panel of human gastric cancer cell lines. MGC803 and HGC 27 gastric cancer cell lines expressing high level of SPARC were transiently transfected with SPARC-specific small interfering RNAs and subsequently evaluated for effects on invasion and proliferation.
Small interfering RNA-mediated knockdown of SPARC in MGC803 and HGC 27 gastric cancer cells dramatically decreased their invasion. Knockdown of SPARC was also observed to significantly increase the apoptosis of MGC803 and HGC 27 gastric cancer cells compared with control transfected group.
Our data showed that downregulating of SPARC inhibits invasion and growth of human gastric cancer cells. Thus, targeting of SPARC could be an effective therapeutic approach against gastric cancer.
Epigenetic silencing of tumor suppressor genes associated with promoter methylation is considered to be a hallmark of oncogenesis. RASSF1A is a candidate tumor suppressor gene which was found to be inactivated in many human cancers. Although we have had a prelimilary cognition about the function of RASSF1A, the exact mechanisms about how RASSF1A functions in human cancers were largely unknown. Moreover, the effect of mutated K-Ras gene on the function of RASSF1A is lacking. The aim of this study was to investigate the expression profile and methylation status of RASSF1A gene, and to explore its concrete mechanisms as a tumor suppressor gene in Nasopharyngeal Carcinoma.
We examined the expression profile and methylation status of RASSF1A in two NPC cell lines, 38 primary nasopharyngeal carcinoma and 14 normal nasopharyngeal epithelia using RT-PCR and methylated specific PCR(MSP) respectively. 5-aza-dC was then added to confirm the correlation between hypermethylation status and inactivation of RASSF1A. The NPC cell line CNE-2 was transfected with exogenous pcDNA3.1(+)/RASSF1A plasmid in the presence or absence of mutated K-Ras by liposome-mediated gene transfer method. Flow cytometry was used to examine the effect of RASSF1A on cell cycle modulation and apoptosis. Meanwhile, trypan blue dye exclusion assays was used to detect the effect of RASSF1A transfection alone and the co-transfection of RASSF1A and K-Ras on cell proliferation.
Promoter methylation of RASSF1A could be detected in 71.05% (27/38) of NPC samples, but not in normal nasopharyngeal epithelia. RASSF1A expression in NPC primary tumors was lower than that in normal nasopharyngeal epithelial (p < 0.01). Expression of RASSF1A was down-regulated in two NPC cell lines. Loss of RASSF1A expression was greatly restored by the methyltransferase inhibitor 5-aza-dC in CNE-2. Ectopic expression of RASSF1A in CNE-2 could increase the percentage of G0/G1 phase cells (p < 0.01), inhibit cell proliferation and induce apoptosis (p < 0.001). Moreover, activated K-Ras could enhance the growth inhibition effect induced by RASSF1A in CNE-2 cells (p < 0.01).
Expression of RASSF1A is down-regulated in NPC due to the hypermethylation of promoter. Exogenous expression of RASSF1A is able to induce growth inhibition effect and apoptosis in tumor cell lines, and this effect could be enhanced by activated K-Ras.
CENP-E, one of spindle checkpoint proteins, plays a crucial role in the function of spindle checkpoint. Once CENP-E expression was interrupted, the chromosomes can not separate procedurally, and may result in aneuploidy which is a hallmark of most solid cancers, such as hepatocellular carcinoma (HCC). We investigate the expression of CENP-E in human hepatocellular carcinoma,. and analyze the effect of low CENP-E expression on chromosome separation in normal liver cell line (LO2).
We determined its levels in HCC and para-cancerous tissues, human hepatocellular carcinoma-derived cell line (HepG2) and LO2 cell line using real time quantitative PCR (QPCR) and Western blot. Further to know whether reduction in CENP-E expression impairs chromosomes separation in LO2 cells. we knocked down CENP-E using shRNA expressing vector and then count the aneuploid in LO2 cells using chromosomal counts assay.
We found that both CENP-E mRNA and protein levels were significantly reduced in HCC tissues and HepG2 cells compared with para-cancerous tissues and LO2 cells, respectively. A significantly-increased proportion of aneuploid in these down-knocked LO2 cells compared with those treated with control shRNA vector.
Together with other results, these results reveal that CENP-E expression was reduced in human HCC tissue, and low CENP-E expression result in aneuploidy in LO2 cells.
Lewis y antigen is difucosylated oligosaccharide and is carried by glycoconjugates at cell surface. Elevated expression of Lewis y has been found in 75% of ovarian tumor, and the high expression level is correlated to the tumor's pathological staging and prognosis. This study was to investigate the effect and the possible mechanism of Lewis y on the proliferation of human ovarian cancer cells.
We constructed a plasmid encoding α1,2-fucosyltransferase (α1,2-FT) gene and then transfected it into ovarian carcinoma-derived RMG-I cells with lowest Lewis y antigen expression level. Effect of Lewis y on cell proliferation was assessed after transfection. Changes in cell survival and signal transduction were evaluated after α-L-fucosidase, anti-Lewis y antibody and phosphatidylinositol 3-kinase (PI3K) inhibitor treatment.
Our results showed that the levels of α1,2-FT gene and Lewis y increased significantly after transfection. The cell proliferation of ovarian carcinoma-derived RMG-I cells sped up as the Lewis y antigen was increased. Both of α-L-fucosidase and anti-Lewis y antibody inhibited the cell proliferation. The phosphorylation level of Akt was apparently elevated in Lewis y-overexpressing cells and the inhibitor of PI3K, LY294002, dramatically inhibited the growth of Lewis y-overexpressing cells. In addition, the phosphorylation intensity and difference in phosphorylation intensity between cells with different expression of α1,2-FT were attenuated significantly by the monoantibody to Lewis y and by the PI3K inhibitor LY294002.
Increased expression of Lewis y antigen plays an important role in promoting cell proliferation through activating PI3K/Akt signaling pathway in ovarian carcinoma-derived RMG-I cells. Inhibition of Lewis y expression may provide a new therapeutic approach for Lewis y positive ovarian cancer.
This study was designed to mainly evaluate the activity and safety of olanzapine compared with 5-hydroxytryptamine3(5-HT3) receptor antagonists for prevention of chemotherapy-induced nausea and vomiting(CINV) in patients receiving highly or moderately emetogenic chemotherapy (HEC or MEC). The second goal was to evaluate the impact of olanzapine on quality of life (QoL) of cancer patients during the period of chemotherapy.
229 patients receiving highly or moderately emetogenic chemotherapy were randomly assigned to the test group [olanzapine(O) 10 mg p.o. plus azasetron (A) 10 mg i.v. and dexamethasone (D) 10 mg i.v. on day 1; O 10 mg once a day on days 2-5] or the control group (A 10 mg i.v. and D 10 mg i.v. on day 1; D 10 mg i.v. once a day on days 2-5). All the patients filled the observation table of CINV once a day on days 1-5, patients were instructed to fill the EORTC QLQ-C30 QoL observation table on day 0 and day 6. The primary endpoint was the complete response (CR) (without nausea and vomiting, no rescue therapy) for the acute period (24 h postchemotherapy), delayed period (days 2-5 poschemotherapy), the whole period (days 1-5 postchemotherapy). The second endpoint was QoL during chemotherapy administration, drug safety and toxicity.
229 patients were evaluable for efficacy. Compared with control group, complete response for acute nausea and vomiting in test group had no difference (p > 0.05), complete response for delayed nausea and vomiting in patients with highly emetogenic chemotherapy respectively improved 39.21% (69.64% versus 30.43%, p < 0.05), 22.05% (78.57% versus 56.52%, p < 0.05), complete response for delayed nausea and vomiting in patients with moderately emetogenic chemotherapy respectively improved 25.01% (83.07% versus 58.06%, p < 0.05), 13.43% (89.23% versus 75.80%, p < 0.05), complete response for the whole period of nausea and vomiting in patients with highly emetogenic chemotherapy respectively improved 41.38% (69.64% versus 28.26%, p < 0.05), 22.05% (78.57% versus 56.52%, p < 0.05), complete response for the whole period of nausea and vomiting in patients with moderately emetogenic chemotherapy respectively improved 26.62% (83.07% versus 56.45%, p < 0.05), 13.43% (89.23% versus 75.80%, p < 0.05). 214 of 299 patients were evaluable for QoL. Comparing test group with control group in QoL evolution, significant differences were seen in global health status, emotional functioning, social functioning, fatigue, nausea and vomiting, insomnia and appetite loss evolution in favour of the test group (p < 0.01). Both treatments were well tolerated.
Olanzapine can improve the complete response of delayed nausea and vomiting in patients receiving the highly or moderately emetogenic chemotherapy comparing with the standard therapy of antiemesis, as well as improve the QoL of the cancer patients during chemotherapy administration. Olanzapine is a safe and efficient drug for prevention of CINV.
Recent data have redefined the concept of inflammation as a critical component of tumor progression. However, there has been little development on cases where inflammation on or near a wound and a tumor exist simultaneously. Therefore, this pilot study aims to observe the impact of a wound on a tumor, to build a new mouse tumor model with a manufactured surgical wound representing acute inflammation, and to evaluate the relationship between acute inflammation or wound healing and the process of tumor growth. We focus on the two phases that are present when acute inflammation influences tumor. In the early phase, inhibitory effects are present. The process that produces these effects is the functional reaction of IFN-γ secretions from a wound inflammation. In the latter phase, the inhibited tumor is made resistant to IFN-γ through the release of TGF-β to balance the inflammatory factor effect on the tumor cells. A pair of cytokines IFN-γ/TGF-β established a new balance to protect the tumor from the interference effect of the inflammation. The tumor was made resistant to IFN-γ through the release of TGF-β to balance the inflammatory effect on the tumor cells. This balance mechanism that occurred in the tumor cells increased proliferation and invasion. In vitro and in vivo experiments have confirmed a new view of clinical surgery that will provide more detailed information on the evaluation of tumors after surgery. This study also provides a better understanding of the relationship between tumor and inflammation, as well as tumor cell attacks on inflammatory factors.
Astrocyte elevated gene-1 (AEG-1) was originally characterized as a HIV-1-inducible gene in primary human fetal astrocyte. Recent studies highlight a potential role of AEG-1 in promoting tumor progression and metastasis. The aim of this study was to investigate if AEG-1 serves as a potential therapeutic target of human neuroblastoma.
We employed RNA interference to reduce AEG-1 expression in human neuroblastoma cell lines and analyzed their phenotypic changes.
We found that the knockdown of AEG-1 expression in human neuroblastoma cells significantly inhibited cell proliferation and apoptosis. The specific downregulation induced cell arrest in the G0/G1 phase of cell cycle. In the present study, we also observed a significant enhancement of chemo-sensitivity to cisplatin and doxorubicin by knockdown of AEG-1.
Our study suggests that overexpressed AEG-1 enhance the tumorogenic properties of neuroblastoma cells. The inhibition of AEG-1 expression could be a new adjuvant therapy for neuroblastoma.
RNA interference (RNAi) has been successfully applied in suppression of hepatic cancer genes. In hepatocelluar carcinoma cell, one methionine adenosyltransferase (MAT) isozyme, MATII was found to have two catalytic subunits which were encoded by MAT2A and MAT2β respectively. During tumorigeness of hepatocelluar carcinoma, expressions of the two genes were discovered to be increased combining with a switch of MAT (form MATI to MATII), To figure out the role played by MATII in hepatic cancer, In this study, for the first time we established a dual small interfering RNA (siRNA) expression system, which could simultaneously express two different siRNA molecules specifically targeting two genes. To test the effectiveness of this system, we applied this approach to express simultaneously two different siRNA duplexes that specifically target MAT2A and MAT2β genes of hepatocelluar carcinoma respectively in HepG2 cell. Results indicated that dual siRNA could simultaneously inhibit the expression of MAT2A and MAT2β gene by 89.5% and 97.8% respectively, In addition, dual siRNA molecules were able to significantly suppress growth of hepatocelluar carcinoma cell in vitro as well as induce apoptosis which was involved in arrest cell cycle at the G1/S checkpoint and the expressions of p21, p27 and Bax.
Sunitinib alone exhibits satisfactory efficacy in several mouse homografts and xenografts but unsatisfactory efficacy in many kinds of solid tumors in clinic. Different from animals, receiving a diagnosis of cancer impacts chronic stress on patients. Here, we examine whether norepinephrine (NE), one of the most potent stress related hormones, leads to the difference in the efficacy of sunitinib between clinical and preclinical trials.
The influence of NE on mouse melanoma B16F1 cells under sunitinib was evaluated in vitro and in vivo. The β-AR/cAMP/PKA (β-adrenoceptor/cyclic adenosine monophosphate/protein kinase A) signaling pathway was also evaluated in human lung adenocarcinoma cells.
We found that NE upregulated the expression of VEGF, IL-8 and IL-6 in vitro and stimulated tumor growth in vivo, which was mediated by β-AR/cAMP/PKA signaling pathway and could be inhibited by propranolol, a β-blocker for hypertension for decades.
This research indicates exogenous norepinephrine attenuates the efficacy of sunitinib, and a combination of sunitinib and propranolol might be suggested as a new strategy in solid tumor in clinic.
Tumor; Chronic stress; Norepinephrine; Sunitinib; Propranolol
NAD (P) H: quinone oxidoreductase 1 (NQO1) is a xenobiotic metabolizing enzyme that detoxifies chemical stressors and antioxidants, providing cytoprotection in normal tissues. However, high-level expression of NQO1 has been correlated with numerous human malignancies, suggesting a role in carcinogenesis and tumor progression. This study aimed to explore the clinicopathological significance of NQO1 and as a prognostic determinant in breast cancer.
A total of 176 breast cancer patients with strict follow-up, 45 ductal carcinoma in situ (DCIS), 22 hyperplasia and 52 adjacent non-tumor breast tissues were selected for immunohistochemical staining of NQO1 protein. Immunofluorescence staining was also performed to detect the subcellular localization of NQO1 protein in MCF-7 breast cancer cells. Eight fresh breast cancers paired with adjacent non-tumor tissues were quantified using real time RT-PCR (qRT-PCR) and western blot. The correlations between NQO1 overexpression and the clinical features of breast cancer were evaluated using chi-square test and Fisher’s exact tests. The survival rate was calculated using the Kaplan–Meier method, and the relationship between prognostic factors and patient survival was also analyzed by the Cox proportional hazards models.
NQO1 protein showed a mainly cytoplasmic staining pattern in breast cancer. The strongly positive rate of NQO1 protein was 61.9% (109/176) in breast cancer, and was significantly higher than in DCIS (31.1%, 14/45), hyperplasia tissues (13.6%, 3/22) and adjacent non-tumor tissues (13.5%, 7/52). High-level expression of NQO1 protein was correlated with late clinical stage, poor differentiation, lymph node metastasis, Her2 expression and disease-free and 10-year overall survival rates in breast cancer. Moreover, multivariate analysis suggested that NQO1 emerged as a significant independent prognostic factor along with clinical stage and Her2 expression status in patients with breast cancer.
High-level expression of NQO1 appears to be associated with breast cancer progression, and may be a potential biomarker for poor prognostic evaluation of breast cancers.
Breast cancer; NQO1; Immunohistochemistry; Prognosis
miRNAs are involved in osteosarcoma (OS) chemoresistance, and TWIST reportedly enhances cisplatin-induced OS cell apoptosis by inhibiting multiple signaling pathways. In this study, we profiled miRNAs differentially expressed in chemoresistant OS, with a focus to identify miRNAs that regulate TWIST expression and OS chemoresistance.
OS patients who showed <90% tumor necrosis after neochemotherapy were defined as poor responders (chemoresistant), and those who showed ≥90% tumor necrosis were defined as good responders (control). miRNA microarray analysis was carried out with a discovery cohort (n = 12) of age-, sex- and tumor stage-matched chemoresistant and control OS patients.
Among the up-regulated miRNAs in chemoresistant OS samples, miR-33a was verified to down-regulate TWIST expression, which was supported by an inverse miRNA-33a/TWIST expression trend in the validation cohort (n = 70), target-sequence-specific inhibition of TWIST-3′ untranslated region-luciferase reporter activity by miR-33a, and alteration of TWIST expression by overexpression or inhibition of miR-33a in human OS cell lines. In Saos-2 cells treated with cisplatin, inhibition of miR-33a by antagomir-33a markedly increased cell apoptosis, which was enhanced by overexpression of TWIST. The apoptosis-inducing effect of TWIST overexpression was reversed by overexpression of miR-33a. In MG-63 cells, overexpression of miR-33a significantly decreased cisplatin-induced cell apoptosis, which was enhanced by knockdown of TWIST. Antagomir-33a significantly increased cisplatin-induced cell apoptosis, which was reversed by knockdown of TWIST.
We have demonstrated in this study that miR-33a is up-regulated in chemoresistant OS and that the miR-33a level is negatively correlated with the TWIST protein level in OS. Our in vitro data indicate that miR-33a promotes OS cell resistance to cisplatin by down-regulating TWIST; on the other hand, inhibition of miR-33a by antagomir-33a enhances cisplatin-induced apoptosis in OS cells by up-regulating TWIST expression. The findings suggest that inhibition of miR-33a/TWIST signaling could be a potential new strategy to enhance neoadjuvant chemotherapy for OS.
microRNA; miR-33a; TWIST; Osteosarcoma; Chemoresistance; Apoptosis
Hec1 (NDC80) is an integral part of the kinetochore and is overexpressed in a variety of human cancers, making it an attractive molecular target for the design of novel anticancer therapeutics. A highly potent first-in-class compound targeting Hec1, TAI-1, was identified and is characterized in this study to determine its potential as an anticancer agent for clinical utility.
The in vitro potency, cancer cell specificity, synergy activity, and markers for response of TAI-1 were evaluated with cell lines. Mechanism of action was confirmed with western blotting and immunofluorescent staining. The in vivo potency of TAI-1 was evaluated in three xenograft models in mice. Preliminary toxicity was evaluated in mice. Specificity to the target was tested with a kinase panel. Cardiac safety was evaluated with hERG assay. Clinical correlation was performed with human gene database.
TAI-1 showed strong potency across a broad spectrum of tumor cells. TAI-1 disrupted Hec1-Nek2 protein interaction, led to Nek2 degradation, induced significant chromosomal misalignment in metaphase, and induced apoptotic cell death. TAI-1 was effective orally in in vivo animal models of triple negative breast cancer, colon cancer and liver cancer. Preliminary toxicity shows no effect on the body weights, organ weights, and blood indices at efficacious doses. TAI-1 shows high specificity to cancer cells and to target and had no effect on the cardiac channel hERG. TAI-1 is synergistic with doxorubicin, topotecan and paclitaxel in leukemia, breast and liver cancer cells. Sensitivity to TAI-1 was associated with the status of RB and P53 gene. Knockdown of RB and P53 in cancer cells increased sensitivity to TAI-1. Hec1-overexpressing molecular subtypes of human lung cancer were identified.
The excellent potency, safety and synergistic profiles of this potent first-in-class Hec1-targeted small molecule TAI-1 show its potential for clinically utility in anti-cancer treatment regimens.
Hec1; NDC80; Anti-cancer drug; Therapeutics; Mitosis; Apoptosis; P53; Retinoblastoma gene; Markers for response
Parthenolide (PTL) is a sesquiterpene lactone which can induce apoptosis in cancer cells and eradicate cancer stem cells such as leukemia stem cells, prostate tumor-initiating cells and so on. However, the mechanism remains largely unclear.
Lung cancer cells were treated with parthenolide and the cell lysates were prepared to detect the given proteins by Western Blot analysis, and the cell survival was assayed by SRB and MTT assay. Cell cycle was evaluated by DNA flow cytometry analysis. TNFRSF10B, PMAIP1, ATF4 and DDIT3 genes were knocked down by siRNA technique. Apoptosis was evaluated by using Annexin V-FITC/PI staining and flow cytometry analysis.
Parthenolide (PTL) induces apoptosis and cell cycle arrest in human lung cancer cells. Moreover, PTL treatment in NSCLC cells increases expression of TNFRSF10B/DR5 and PMAIP1/NOXA. Silencing of TNFRSF10B or PMAIP1 or overexpression of CFLAR /c-FLIP (long form) could protect cells from PTL-induced apoptosis. Furthermore, PTL could increase the levels of endoplasmic reticulum stress hallmarks such as ERN1, HSPA5, p-EIF2A, ATF4 and DDIT3. Knockdown of ATF4 and DDIT3 abrogated PTL-induced apoptosis, which suggested that PTL induced apoptosis in NSCLC cells through activation of endoplasmic reticulum stress pathway. More importantly, we found that ATF4, DDIT3, TNFRSF10B and PMAIP1 were up-regulated more intensively, while CFLAR and MCL1 were down-regulated more dramatically by PTL in A549/shCDH1 cells than that in control cells, suggesting that PTL preferred to kill cancer stem cell-like cells by activating more intensive ER stress response in cancer stem cell-like cells.
We showed that parthenolide not only triggered extrinsic apoptosis by up-regulating TNFRSF10B and down-regulating CFLAR, but also induced intrinsic apoptosis through increasing the expression of PMAIP1 and decreasing the level of MCL1 in NSCLC cells. In addition, parthenolide triggered stronger ER stress response in cancer stem cell-like cells which leads to its preference in apoptotic induction. In summary, PTL induces apoptosis in NSCLC cells by activating endoplasmic reticulum stress response.
Parthenolide; TNFRSF10B; CFLAR; PMAIP1; Endoplasmic reticulum stress; DDIT3
Numerous studies have yielded inconclusive results regarding the relationship between anti-apoptotic protein Bcl-2 expression and the sensitivity to chemotherapy in the patients with breast cancer. The purpose of the current study was therefore to elaborate their relationship.
A total of 23 previously published eligible studies involving 2,467 cases were identified and included in this meta-analysis. Negative Bcl-2 expression was associated with good chemotherapy response in breast cancer patients (total objective response [OR]: risk ratio [RR] = 1.16, 95% confidence interval [CI] = 1.02-1.32, p = 0.026; total complete response [CR]: RR = 1.67, 95% CI = 1.24-2.24, p = 0.001; pathological CR: RR = 1.92, 95% CI = 1.38-2.69, p < 0.001). In further stratified analyses, this association remained for sub-groups of response in neoadjuvant chemotherapy setting, especially pathological CR. Besides, negative Bcl-2 expression was significantly associated with good OR and pathological CR in anthracycline-based chemotherapy subgroup. Furthermore, there were significant links between negative Bcl-2 expression and taxane-based chemotherapy with pathological CR, but not OR.
The results of the present meta-analysis suggest that Bcl-2 expression is a predictive factor for chemotherapy sensitivity in breast cancer patients. They could also potentially benefit further clinical treatment for breast cancers.
Bcl-2; Breast cancer; Chemotherapy; Response