Immune checkpoint inhibitors targeting programmed cell death 1 (PD1) or its ligand (PD-L1) showed activity in several cancer types.
We performed immunohistochemistry for CD3, CD8, CD20, HLA-DR, phosphatase and tensin homolog (PTEN), PD-1, and PD-L1 and pyrosequencing for assessment of the O6-methylguanine-methyltransferase (MGMT) promoter methylation status in 135 glioblastoma specimens (117 initial resection, 18 first local recurrence). PD-L1 gene expression was analyzed in 446 cases from The Cancer Genome Atlas.
Diffuse/fibrillary PD-L1 expression of variable extent, with or without interspersed epithelioid tumor cells with membranous PD-L1 expression, was observed in 103 of 117 (88.0%) newly diagnosed and 13 of 18 (72.2%) recurrent glioblastoma specimens. Sparse-to-moderate density of tumor-infiltrating lymphocytes (TILs) was found in 85 of 117 (72.6%) specimens (CD3+ 78/117, 66.7%; CD8+ 52/117, 44.4%; CD20+ 27/117, 23.1%; PD1+ 34/117, 29.1%). PD1+ TIL density correlated positively with CD3+ (P < .001), CD8+ (P < .001), CD20+ TIL density (P < .001), and PTEN expression (P = .035). Enrichment of specimens with low PD-L1 gene expression levels was observed in the proneural and G-CIMP glioblastoma subtypes and in specimens with high PD-L1 gene expression in the mesenchymal subtype (P = 5.966e-10). No significant differences in PD-L1 expression or TIL density between initial and recurrent glioblastoma specimens or correlation of PD-L1 expression or TIL density with patient age or outcome were evident.
TILs and PD-L1 expression are detectable in the majority of glioblastoma samples but are not related to outcome. Because the target is present, a clinical study with specific immune checkpoint inhibitors seems to be warranted in glioblastoma.
glioblastoma; immune checkpoint; programmed death 1; programmed death ligand 1
Personalized treatment of patients with advanced non-small-cell lung cancer based on clinical and molecular tumor features has entered clinical routine practice. The 2015 pathological classification of lung cancer mandates immunohistochemical and molecular analysis. Therapeutic strategies focused on inhibition of angiogenesis and growth factor receptor signaling. Inhibitors of angiogenesis and monoclonal antibodies directed against the epidermal growth factor receptor have shown efficacy in combination with chemotherapy. Mutations in the epidermal growth factor receptor and anaplastic lymphoma kinase have become clinically relevant therapeutic targets. Immune checkpoint inhibitors are also entering routine clinical practice. Identification of predictive biomarkers is essential and faces several challenges including tumor heterogeneity and dynamic changes of tumor features over time. Liquid biopsies may overcome some of these challenges in the future.
ALK; Biomarker; Cetuximab; EGFR mutations; Liquid biopsy; Necitumumab
Myeloid cells lacking STAT3 promote antitumor responses of NK and T cells but it is unknown if this crosstalk affects development of autochthonous tumors. We deleted STAT3 in murine myeloid cells (STAT3Δm) and examined the effect on the development of autochthonous colorectal cancers (CRCs). Formation of Azoxymethane/Dextransulfate (AOM/DSS)-induced CRCs was strongly suppressed in STAT3Δm mice. Gene expression profiling showed strong activation of T cells in the stroma of STAT3Δm CRCs. Moreover, STAT3Δm host mice were better able to control the growth of transplanted MC38 colorectal tumor cells which are known to be killed in a T cell-dependent manner. These data suggest that myeloid cells lacking STAT3 control formation of CRCs mainly via cross activation of T cells. Interestingly, the few CRCs that formed in STAT3Δm mice displayed enhanced stromalization but appeared normal in size indicating that they have acquired ways to escape enhanced tumor surveillance. We found that CRCs in STAT3Δm mice consistently activate STAT3 signaling which is implicated in immune evasion and might be a target to prevent tumor relapse.
immune surveillance; immunoediting; tumor microenvironment; tumor stroma; AOM, Azoxymethane, CRC, colorectal cancer; DSS, Dextransulfate; IHC, immunohistochemistry; STAT3, signal transducer and activator of transcription 3; TAM, tumor-associated macrophage
RET fusions have been recognized as potential therapeutic targets in advanced non-small cell lung cancer. RET fusion proteins are detected in about 2% of lung adenocarcinomas. Alectinib, a second generation ALK inhibitor, was shown to block growth of cells with RET fusions. Thus alectinib should be further evaluated within clinical trials in patients with RET fusion-positive adenocarcinomas of the lung.
Alectinib; biomarker; RET; targeted therapy; tyrosine kinase inhibitor
BACKGROUND: Differences in the adaptive immune response to various kinds of brain tumors have been poorly characterized. METHODS: We immunostained 287 neurosurgical specimens: 170 BM (lung cancer: 77 (45.3%); breast cancer: 17 (10.0%); melanoma 44 (25.9%); renal cell carcinoma 10 (5.9%) others 22 (7.7%)) and 117 GBM for CD3 (n = 287), CD8 (n = 287), PD1 (n = 287) and PDL1 (n = 234) and used previously published semiquantitative evaluation criteria. RESULTS: TIL infiltration of variable density (sparse to dense) was found in 161/170 (94.7%) BM and 78/117 (66.6%) GBM. TILs were predominantly present in the tumor stroma and perivascular areas in BM and in perivascular area in GBM. Dense infiltration with CD3+ TILs (p < 0.001), CD8+ TILs (p < 0.001) and PD1+ TILs (p < 0.001) was observed more frequently in BM than GBM. Among BM, we found significant differences in the composition of immune infiltrates with renal cell carcinoma BM showing the highest density of CD3+ and PD1+ TILs. Membranous PDL1 expression on tumor cells was evident in 25/117 (21.4%) BM and 44/117 (37.6%) GBM. Expression of PDL1 in over 5% of tumor cells was more frequently observed in GBM than in BM (p = 0.006). Dense infiltration of CD3+ TILs (9 vs. 12 months; p = 0.015) correlated with favorable survival prognosis in BM patients, while no prognostic impact of TIL infiltration was evident in GBM. Expression of PDL1 in over 5% of tumor cells was not associated with survival prognosis in BM (11 vs. 11 months; p = 0.395) or GBM (15 vs. 14 months; p = 0.859). CONCLUSION: We found high TIL densities and prognostic impact of CD3+ immune infiltrates in BM. GBM was characterized by sparse TIL infiltrates, higher expression of PDL1 and lack of prognostic impact of immune infiltrates. Our results indicate clinically relevant differences in the immune response to brain tumor types and may be of interest for studies with immunomodulatory agents.
In light of the controversial published literature, this study aims to examine the potential prognostic role of AR immunohistochemical expression in triple negative breast cancer (TNBC).
Patients and methods
Ninety patients with TNBC were included in this study; the associations between AR expression (Allred score), clinicopathological variables (stage, grade, histological subtype, tumor size, nodal status, age at diagnosis, Ki67 expression, and p53 expression), and overall survival were evaluated.
AR expression was not associated with stage, grade, histological subtype, tumor size, nodal status, age at diagnosis, Ki67 expression, and p53 expression. AR immunopositivity was not associated with overall survival either at the univariate or at the multivariate Cox regression analysis (multivariate hazard ratio =0.66, 95% confidence interval: 0.26–1.70, P=0.393).
AR expression does not seem to play a prognostic role in TNBC.
biomarkers; prognosis; AR; triple negative breast cancer
During the last decade, besides the well-established clinical-pathological predictors for the risk of late recurrence in breast cancer, such as estrogen receptor status, and T and N stage, a variety of multigene assays have been shown to improve prognostication and prediction in this setting. Several clinical trials have evaluated the role of extended endocrine therapy with tamoxifen (ATLAS) or aromatase inhibitors (MA.17, NSABP-B33 and ABCSG 6a), and other randomized studies are still ongoing. However, among this patient population, it is still not clear who could benefit from extended therapy and what the optimal treatment duration should be. New multigene assays such as EndoPredict, PAM50 ROR-score, HOXB13/IL17BR ratio and Breast Cancer Index provide significant and relevant prognostic information concerning the likelihood of recurrence beyond 5 years after surgery. The identified low-risk subgroups not only show a very favorable prognosis, they also seem to have only little benefit from extended aromatase inhibitor therapy. Many of these reverse transcriptase/polymerase chain reaction-based techniques have been validated in archived tumor material from large phase III trials, and will soon be available to routine pathology laboratories as an aid in clinical decision-making for patients.
Breast neoplasms; Late metastasis; Endocrine therapy; Prediction
The transcription factor Ecotropic Virus Integration site 1 (EVI1) regulates cellular proliferation, differentiation, and apoptosis, and its overexpression contributes to an aggressive course of disease in myeloid leukemias and other malignancies. Notwithstanding, knowledge about the target genes mediating its biological and pathological functions remains limited. We therefore aimed to identify and characterize novel EVI1 target genes in human myeloid cells.
U937T_EVI1, a human myeloid cell line expressing EVI1 in a tetracycline regulable manner, was subjected to gene expression profiling. qRT-PCR was used to confirm the regulation of membrane-spanning-4-domains subfamily-A member-3 (MS4A3) by EVI1. Reporter constructs containing various parts of the MS4A3 upstream region were employed in luciferase assays, and binding of EVI1 to the MS4A3 promoter was investigated by chromatin immunoprecipitation. U937 derivative cell lines experimentally expressing EVI1 and/or MS4A3 were generated by retroviral transduction, and tested for their tumorigenicity by subcutaneous injection into severe combined immunodeficient mice.
Gene expression microarray analysis identified 27 unique genes that were up-regulated, and 29 unique genes that were down-regulated, in response to EVI1 induction in the human myeloid cell line U937T. The most strongly repressed gene was MS4A3, and its down-regulation by EVI1 was confirmed by qRT-PCR in additional, independent experimental model systems. MS4A3 mRNA levels were also negatively correlated with those of EVI1 in several published AML data sets. Reporter gene assays and chromatin immunoprecipitation showed that EVI1 regulated MS4A3 via direct binding to a promoter proximal region. Experimental re-expression of MS4A3 in an EVI1 overexpressing cell line counteracted the tumor promoting effect of EVI1 in a murine xenograft model by increasing the rate of apoptosis.
Our data reveal MS4A3 as a novel direct target of EVI1 in human myeloid cells, and show that its repression plays a role in EVI1 mediated tumor aggressiveness.
Electronic supplementary material
The online version of this article (doi:10.1186/s13045-015-0124-6) contains supplementary material, which is available to authorized users.
EVI1; MS4A3; Transcriptional repression; Myeloid leukemia; Tumor growth
The individual risk of recurrence in hormone receptor-positive primary breast cancer patients determines whether adjuvant endocrine therapy should be combined with chemotherapy. Clinicopathological parameters and molecular tests such as EndoPredict® (EPclin) can support decision making in patients with estrogen receptor-positive, human epidermal growth factor receptor 2 (HER2)-negative cancer.
Using a life-long Markov state transition model, we determined the health economic impact and incremental cost effectiveness of EPclin-based risk stratification in combination with clinical guidelines [German-S3, National Comprehensive Cancer Center Network (NCCN), and St. Gallen] to decide on chemotherapy use.
Information on overall and metastasis-free survival came from Austrian Breast & Colorectal Cancer Study Group clinical trials 6/8 (n = 1,619) and published literature. Effectiveness was assessed as quality-adjusted life-years (QALYs). Costs (2010) were assessed from a German third-party payer perspective.
Lifetime costs per patient ranged from €28,268 (St.Gallen and EPclin) to €33,756 (NCCN). Due to an imperfect prognostic value and differences in chemotherapy use, strategies achieved between 13.165 QALYs (NCCN) and 13.173 QALYs (EPclin alone) per patient. Using German-S3 as reference, three strategies showed dominant results (St. Gallen and EPclin, German-S3 and EPclin, EPclin alone). Compared to German-S3, the addition of EPclin saved €3,388 and gained 0.002 QALYs per patient. Combining guidelines with EPclin remained preferable in sensitivity analysis.
Our study suggests that molecular markers can be sensibly combined with clinical guidelines to determine the risk profile of adjuvant breast cancer patients. Compared with the current German best practice (German-S3), combinations of EPclin with the St. Gallen, German-S3 or NCCN guideline and EPclin alone were dominant from the perspective of the German healthcare system.
Electronic supplementary material
The online version of this article (doi:10.1007/s40273-014-0227-x) contains supplementary material, which is available to authorized users.
The discovery of activating epidermal growth factor receptor (EGFR) mutations and chromosomal rearrangements involving the anaplastic lymphoma kinase (ALK) gene or the ROS1 gene has improved the treatment in patients with advanced non-small cell lung cancer (NSCLC). Activating EGFR mutations occur in about 10% of lung adenocarcinomas and are associated with high response rates and longer progression-free survival (PFS) to EGFR TKIs. ALK rearrangements are observed in 3-5% and ROS1 rearrangements in 1-2% of lung adenocarcinomas. ALK inhibitors have been shown to be particularly effective in these patients. In order to obtain more data on patients harboring EGFR, ALK, or ROS1 mutations in their tumors, a registry study will be performed. This registry is planned for 3 years and will be a multicentre, observational registry study. Approximately 15 sites in Austria will participate in this registry. It is expected that about 180 cases per year will be documented and, therefore, the total number of patients will be about 540. The objectives of the study are: (I) to evaluate the distribution of EGFR, ALK, or ROS1 mutations; (II) detection methods used in clinical routine and frequency of mutation testing; (III) to gather more data on treatment (first-line, second-line, later lines) including outcome of patients harboring these mutations in their tumors; (IV) re-biopsy at the time of disease progression in routine practice particularly in patients treated with molecular targeted therapy will be assessed; (V) mutations or genetic alterations at the time of relapse and the treatment of patients refractory to first-line EGFR TKI or ALK inhibitor treatment will be studied; (VI) treatment of patients at the time of disease progression; (VII) virtual tumor bank (decentralized stored material).
Non-small cell lung cancer (NSCLC); epidermal growth factor receptor (EGFR); ALK; ROS1; mutation
CALGB 9633 was a randomized trial of observation versus adjuvant chemotherapy for patients with stage IB non-small cell lung cancer (NSCLC). In CALGB 9633, the presence of mucin in the primary tumor was associated with shorter disease-free survival (DFS; hazard ratio (HR)=1.9, p=0.002) and overall survival (OS; HR=1.9, p=0.004).
To validate these results, mucin staining was performed on primary tumor specimens from 780 patients treated on IALT, 351 on JBR.10 and 150 on ANITA. The histochemical technique using mucicarmine was performed. The prognostic value of mucin for DFS and OS was tested in a Cox model stratified by trial and adjusted for clinical and pathological factors. A pooled analysis of all 4 trials was performed for the predictive value of mucin for benefit from adjuvant chemotherapy.
The cross-validation group had 48% squamous, 37% adenocarcinoma and 15% other NSCLC compared with 29%, 56%, and 15% respectively in CALGB. Among 1262 patients with assessable results, mucin was positive in IALT 24%, JBR.10 30%, ANITA 22% compared with 45% in CALGB. Histology was the only significant covariate (p<0.0001) in multivariate analysis with mucin seen more commonly in adenocarcinoma (56%) compared with squamous (5%) and other NSCLC (15%). Mucin was a borderline negative prognostic factor for DFS (HR=1.2 [1.0–1.5], p=0.06) but not significantly so for OS (HR=1.1 [0.9–1.4], p=0.25). Prognostic value did not vary according to histology: HR=1.3 [1.0–1.6] in adenocarcinoma vs. 1.6 [1.2–2.2] for DFS in other histology (interaction p=0.69). Mucin status was not predictive for benefit from adjuvant chemotherapy (test of interaction: DFS p=0.27; OS p=0.49).
Mucin was less frequent in the cross-validation group due to its higher percentage of squamous cell carcinomas. The negative impact of mucin was confirmed for DFS but not for OS. Mucin expression was not predictive of overall survival benefit from adjuvant chemotherapy.
Non-small cell lung cancer; prognostic factors; mucin; predictive factors; adenocarcinoma
The excision repair cross-complementation group 1 (ERCC1) protein is a potential prognostic biomarker of the efficacy of cisplatin-based chemotherapy in non–small-cell lung cancer (NSCLC). Although several ongoing trials are evaluating the level of expression of ERCC1, no consensus has been reached regarding a method for evaluation.
We used the 8F1 antibody to measure the level of expression of ERCC1 protein by means of immunohistochemical analysis in a validation set of samples obtained from 494 patients in two independent phase 3 trials (the National Cancer Institute of Canada Clinical Trials Group JBR.10 and the Cancer and Leukemia Group B 9633 trial from the Lung Adjuvant Cisplatin Evaluation Biology project). We compared the results of repeated staining of the entire original set of samples obtained from 589 patients in the International Adjuvant Lung Cancer Trial Biology study, which had led to the initial correlation between the absence of ERCC1 expression and platinum response, with our previous results in the same tumors. We mapped the epitope recognized by 16 commercially available ERCC1 antibodies and investigated the capacity of the different ERCC1 isoforms to repair platinum-induced DNA damage.
We were unable to validate the predictive effect of immunostaining for ERCC1 protein. The discordance in the results of staining for ERCC1 suggested a change in the performance of the 8F1 antibody since 2006. We found that none of the 16 antibodies could distinguish among the four ERCC1 protein isoforms, whereas only one isoform produced a protein that had full capacities for nucleotide excision repair and cisplatin resistance.
Immunohistochemical analysis with the use of currently available ERCC1 antibodies did not specifically detect the unique functional ERCC1 isoform. As a result, its usefulness in guiding therapeutic decision making is limited. (Funded by Eli Lilly and others.)
Controversy exists regarding CYP2D6 genotype and tamoxifen efficacy.
A matched case-control study was conducted utilizing the Austrian Breast and Colorectal Cancer Study Group Trial 8 that randomized post-menopausal women with estrogen receptor positive breast cancer to tamoxifen for 5 years (Arm A) or tamoxifen for 2 years followed by anastrozole for 3 years (Arm B). Cases had disease recurrence, contralateral breast cancer, second non-breast cancer, or died. For each case, controls were identified from the same treatment arm of similar age, surgery/radiation, and TNM stage. Genotyping was performed for alleles associated with no (PM; *3, *4, *6); reduced (IM; *10, and *41); and extensive (EM: absence of these alleles) CYP2D6 metabolism.
The common CYP2D6 *4 allele was in Hardy Weinberg Equilibrium. In Arm A during the first 5 years of therapy, women with 2 poor alleles (PM/PM: OR=2.45, 95% CI: 1.05–5.73, p=0.04) and women with one poor allele (PM/IM or PM/EM: OR=1.67, 95% CI: 0.95–2.93, p=0.07) had a higher likelihood of an event than women with two extensive alleles (EM/EM). In years 3–5 when patients remained on tamoxifen (Arm A) or switched to anastrozole (Arm B), PM/PM tended towards a higher likelihood of a disease event relative to EM/EM (OR= 2.40, 95% CI: 0.86–6.66, p=0.09) among women on Arm A but not among women on Arm B (OR= 0.28; 95% CI: 0.03–2.30).
In ABCSG8, the negative effects of reduced CYP2D6 metabolism were observed only during the period of tamoxifen administration, and not after switching to anastrozole.
Tamoxifen; CYP2D6; metabolism; anastrozole; breast cancer; estrogen receptor
Testing of the MGMT promoter methylation status in glioblastoma is relevant for clinical decision making and research applications. Two recent and independent phase III therapy trials confirmed a prognostic and predictive value of the MGMT promoter methylation status in elderly glioblastoma patients. Several methods for MGMT promoter methylation testing have been proposed, but seem to be of limited test reliability. Therefore, and also due to feasibility reasons, translation of MGMT methylation testing into routine use has been protracted so far. Pyrosequencing after prior DNA bisulfite modification has emerged as a reliable, accurate, fast and easy-to-use method for MGMT promoter methylation testing in tumor tissues (including formalin-fixed and paraffin-embedded samples). We performed an intra- and inter-laboratory ring trial which demonstrates a high analytical performance of this technique. Thus, pyrosequencing-based assessment of MGMT promoter methylation status in glioblastoma meets the criteria of high analytical test performance and can be recommended for clinical application, provided that strict quality control is performed. Our article summarizes clinical indications, practical instructions and open issues for MGMT promoter methylation testing in glioblastoma using pyrosequencing.
glioblastoma; MGMT; methylation; predictive; prognostic
We undertook this analysis of KRAS mutation in four trials of adjuvant chemotherapy (ACT) versus observation (OBS) to clarify the prognostic/predictive roles of KRAS in non–small-cell lung cancer (NSCLC).
KRAS mutation was determined in blinded fashion. Exploratory analyses were performed to characterize relationships between mutation status and subtype and survival outcomes using a multivariable Cox model.
Among 1,543 patients (763 OBS, 780 ACT), 300 had KRAS mutations (codon 12, n = 275; codon 13, n = 24; codon 14, n = 1). In OBS patients, there was no prognostic difference for overall survival for codon-12 (mutation v wild type [WT] hazard ratio [HR] = 1.04; 95% CI, 0.77 to 1.40) or codon-13 (HR = 1.01; 95% CI, 0.47 to 2.17) mutations. No significant benefit from ACT was observed for WT-KRAS (ACT v OBS HR = 0.89; 95% CI, 0.76 to 1.04; P = .15) or codon-12 mutations (HR = 0.95; 95% CI, 0.67 to 1.35; P = .77); with codon-13 mutations, ACT was deleterious (HR = 5.78; 95% CI, 2.06 to 16.2; P < .001; interaction P = .002). There was no prognostic effect for specific codon-12 amino acid substitution. The effect of ACT was variable among patients with codon-12 mutations: G12A or G12R (HR = 0.66; P = .48), G12C or G12V (HR = 0.94; P = .77) and G12D or G12S (HR = 1.39; P = .48; comparison of four HRs, including WT, interaction P = .76). OBS patients with KRAS-mutated tumors were more likely to develop second primary cancers (HR = 2.76, 95% CI, 1.34 to 5.70; P = .005) but not ACT patients (HR = 0.66; 95% CI, 0.25 to 1.75; P = .40; interaction, P = .02).
KRAS mutation status is not significantly prognostic. The potential interaction in patients with codon-13 mutations requires validation. At this time, KRAS status cannot be recommended to select patients with NSCLC for ACT.
Indazolium trans-[tetrachlorobis(1H-indazole)ruthenate(III)] (1, KP1019) and
(2, KP1339) are promising redox-active anticancer drug
candidates that were investigated with X-ray absorption near edge
structure spectroscopy. The analysis was based on the concept of the
coordination charge and ruthenium model compounds representing possible
coordinations and oxidation states in vivo. 1 was investigated
in citrate saline buffer (pH 3.5) and in carbonate buffer (pH 7.4)
at 37 °C for different time intervals. Interaction studies on 1 with glutathione in saline buffer and apo-transferrin in
carbonate buffer were undertaken, and the coordination of 1 and 2 in tumor tissues was studied too. The most likely
coordinations and oxidation states of the compound under the above
mentioned conditions were assigned. Microprobe X-ray fluorescence
of tumor thin sections showed the strong penetration of ruthenium
into the tumor tissue, with the highest concentrations near blood
vessels and in the edge regions of the tissue samples.
Overexpression of ecotropic viral integration site 1 (EVI1) is associated with aggressive disease in acute myeloid leukemia (AML). Despite of its clinical importance, little is known about the mechanism through which EVI1 confers resistance to antileukemic drugs. Here, we show that a human myeloid cell line constitutively overexpressing EVI1 after infection with a retroviral vector (U937_EVI1) was partially resistant to etoposide and daunorubicin as compared to empty vector infected control cells (U937_vec). Similarly, inducible expression of EVI1 in HL-60 cells decreased their sensitivity to daunorubicin. Gene expression microarray analyses of U937_EVI1 and U937_vec cells cultured in the absence or presence of etoposide showed that 77 and 419 genes were regulated by EVI1 and etoposide, respectively. Notably, mRNA levels of 26 of these genes were altered by both stimuli, indicating that EVI1 regulated genes were strongly enriched among etoposide regulated genes and vice versa. One of the genes that were induced by both EVI1 and etoposide was CDKN1A/p21/WAF, which in addition to its function as a cell cycle regulator plays an important role in conferring chemotherapy resistance in various tumor types. Indeed, overexpression of CDKN1A in U937 cells mimicked the phenotype of EVI1 overexpression, similarly conferring partial resistance to antileukemic drugs.
EndoPredict (EP) is a clinically validated multianalyte gene expression test to predict distant metastasis in ER-positive, HER2-negative breast cancer treated with endocrine therapy alone. The test is based on the combined analysis of 12 genes in formalin-fixed, paraffin-embedded (FFPE) tissue by reverse transcription-quantitative real-time PCR (RT-qPCR). Recently, it was shown that EP is feasible for reliable decentralized assessment of gene expression. The aim of this study was the analytical validation of the performance characteristics of the assay and its verification in a molecular-pathological routine laboratory.
Gene expression values to calculate the EP score were assayed by one-step RT-qPCR using RNA from FFPE tumor tissue. Limit of blank, limit of detection, linear range, and PCR efficiency were assessed for each of the 12 PCR assays using serial samples dilutions. Different breast cancer samples were used to evaluate RNA input range, precision and inter-laboratory variability.
PCR assays were linear up to Cq values between 35.1 and 37.2. Amplification efficiencies ranged from 75% to 101%. The RNA input range without considerable change of the EP score was between 0.16 and 18.5 ng/μl. Analysis of precision (variation of day, day time, instrument, operator, reagent lots) resulted in a total noise (standard deviation) of 0.16 EP score units on a scale from 0 to 15. The major part of the total noise (SD 0.14) was caused by the replicate-to-replicate noise of the PCR assays (repeatability) and was not associated with different operating conditions (reproducibility). Performance characteristics established in the manufacturer’s laboratory were verified in a routine molecular pathology laboratory. Comparison of 10 tumor samples analyzed in two different laboratories showed a Pearson coefficient of 0.995 and a mean deviation of 0.15 score units.
The EP test showed reproducible performance characteristics with good precision and negligible laboratory-to-laboratory variation. This study provides further evidence that the EP test is suitable for decentralized testing in specialized molecular pathological laboratories instead of a reference laboratory. This is a unique feature and a technical advance in comparison with existing RNA-based prognostic multigene expression tests.
Breast cancer; Prognostic multigene expression test; Analytical validation; PCR; Pathology
Cetuximab is a chimeric monoclonal antibody that is directed towards the epidermal growth factor receptor (EGFR). It has been evaluated in combination with first-line chemotherapy in several phase II and two phase III trials in patients with advanced NSCLC. The phase III FLEX trial demonstrated improved survival for cetuximab combined with cisplatin plus vinorelbine compared to chemotherapy alone. The BMS099 trial failed to show a significant improvement in progression-free survival but resulted in a hazard ratio for death similar to the one seen in the FLEX trial. A meta-analysis of four randomized trials confirmed the efficacy of cetuximab when added to chemotherapy. EGFR expression levels based on an immunohistochemistry score have recently been shown to predict benefit from cetuximab in the FLEX trial. In patients with high EGFR expression, patients had prolonged survival when treated with chemotherapy plus cetuximab compared to chemotherapy alone. In patients with low EGFR expression, outcome was not different between the two treatment arms. Thus platinum-based chemotherapy combined with cetuximab represents a new treatment option for patients with advanced NSCLC and high EGFR expression in their tumors. Cetuximab is also evaluated in combination with chemoradiotherapy in patients with stage III NSCLC.
Targeted therapy; cetuximab; EGFR; NSCLC; monoclonal antibodies
Gene expression profiles provide important information about the biology of breast tumors and can be used to develop prognostic tests. However, the implementation of quantitative RNA-based testing in routine molecular pathology has not been accomplished, so far. The EndoPredict assay has recently been described as a quantitative RT-PCR-based multigene expression test to identify a subgroup of hormone–receptor-positive tumors that have an excellent prognosis with endocrine therapy only. To transfer this test from bench to bedside, it is essential to evaluate the test–performance in a multicenter setting in different molecular pathology laboratories. In this study, we have evaluated the EndoPredict (EP) assay in seven different molecular pathology laboratories in Germany, Austria, and Switzerland. A set of ten formalin-fixed paraffin-embedded tumors was tested in the different labs, and the variance and accuracy of the EndoPredict assays were determined using predefined reference values. Extraction of a sufficient amount of RNA and generation of a valid EP score was possible for all 70 study samples (100%). The EP scores measured by the individual participants showed an excellent correlation with the reference values, respectively, as reflected by Pearson correlation coefficients ranging from 0.987 to 0.999. The Pearson correlation coefficient of all values compared to the reference value was 0.994. All laboratories determined EP scores for all samples differing not more than 1.0 score units from the pre-defined references. All samples were assigned to the correct EP risk group, resulting in a sensitivity and specificity of 100%, a concordance of 100%, and a kappa of 1.0. Taken together, the EndoPredict test could be successfully implemented in all seven participating laboratories and is feasible for reliable decentralized assessment of gene expression in luminal breast cancer.
Breast cancer; Prognosis; mRNA; Quality control
This study determined whether expression levels of a panel of biologically relevant microRNAs can be used as prognostic or predictive biomarkers in patients who participated in the International Adjuvant Lung Cancer Trial (IALT), the largest randomized study conducted to date of adjuvant chemotherapy in patients with radically resected non-small cell lung carcinoma (NSCLC). Expression of miR-21, miR-29b, miR-34a/b/c, miR-155 and let-7a was determined by quantitative real-time PCR in paraffin embedded formalin fixed tumor specimens from 639 IALT patients. Prognostic and predictive value of microRNA expression for survival were studied using a Cox model, which included every factor used in the stratified randomization, clinicopathological prognostic factors and other factors statistically related to microRNA expression. Investigation of the expression pattern of microRNAs in situ was performed. We also analyzed association of TP53 mutation status and miR-34a/b/c expression, EGFR and KRAS mutation status and miR-21 and Let-7a expression, respectively. Finally, association of p16 and miR-29b expression was assessed. Overall, no significant association was found between any of the tested microRNAs and survival, with the exception of miR-21 where a deleterious prognostic effect of lowered expression was suggested. Otherwise, no single or combinatorial microRNA expression profile predicted response to adjuvant cisplatin-based chemotherapy. Together, our results indicate that the miRNA expression patterns examined were neither predictive nor prognostic in a large patient cohort of radically resected NSCLC randomized to receive adjuvant cisplatin-based chemotherapy versus follow-up only.
non–small cell lung cancer; adjuvant chemotherapy; randomized trial; biomarker; drug resistance; microRNA
O6-Methylguanine DNA methyltransferase (MGMT) is implicated as a major predictive factor for treatment response to alkylating agents including temozolomide (TMZ) of glioblastoma multiforme (GBM) patients. However, whether the MGMT status in GBM patients should be detected at the level of promoter methylation or protein expression is still a matter of debate. Here, we compared promoter methylation (by methylation-specific polymerase chain reaction) and protein expression (by Western blot) in tumor cell explants with respect to prediction of TMZ response and survival of GBM patients (n = 71). Methylated MGMT gene promoter sequences were detected in 47 of 71 (66%) cases, whereas 37 of 71 (52%) samples were scored positive for MGMT protein expression. Although overall promoter methylation correlated significantly with protein expression (χ2 test, P < .001), a small subgroup of samples did not follow this association. In the multivariate Cox regression model, a significant interaction between MGMT protein expression, but not promoter methylation, and TMZ therapy was observed (test for interaction, P = .015). In patients treated with TMZ (n = 42), MGMT protein expression predicted a significantly shorter overall survival (OS; hazard ratio [HR] for death 5.53, 95% confidence interval [CI] 1.76–17.37; P = .003), whereas in patients without TMZ therapy (n = 29), no differences in OS were observed (HR for death 1.00, 95% CI 0.45–2.20; P = .99). These data suggest that lack of MGMT protein expression is superior to promoter methylation as a predictive marker for TMZ response in GBM patients.
O6-Methylguanine DNA methyltransferase; glioblastoma multiforme; protein expression; temozolomide
Recently, radiopharmaceutical scanning with Tc-99m-MIBI was reported to depict areas with active bone disease in multiple myeloma (MM) with both high sensitivity and specificity. This observation was explained by the uptake of Tc-99m-MIBI by neoplastic cells. The present investigation evaluates whether Tc-99m-MIBI imaging and magnetic resonance imaging (MRI) perform equally well in detecting myelomatous bone marrow lesions.
In 21 patients with MM, MRIs of the vertebral region TH12 to S1 and whole body scans with Tc-99m-MIBI were done.
Tc-99m-MIBI scanning missed bone marrow infiltration in 43 of 87 vertebrae (50.5%) in which MRI showed neoplastic bone marrow involvement. In patients with disease stage I+II, Tc-99m-MIBI scanning was negative in all of 24 vertebrae infiltrated according to MRI. In patients with disease stage III, Tc-99m-MIBI scanning detected 44 of 63 (70%) vertebrae involved by neoplastic disease.
Tc-99m-MIBI scanning underestimated the extent of myelomatous bone marrow infiltration in the spine, especially in patients with low disease stage.