ABSTRACT
BACKGROUND: High tumor mutational burden (TMB) was reported to predict the efficacy of immune checkpoint inhibitors (ICIs). Pembrolizumab, an anti-PD-1, received FDA-approval for the treatment of unresectable/metastatic tumors with high TMB as determined by the FoundationOne®CDx test. It remains to be determined how TMB can also be calculated using other tests. RESULTS: FFPE/frozen tumor samples from various origins were sequenced in the frame of the Institut Curie (IC) Molecular Tumor Board using an in-house next-generation sequencing (NGS) panel. A TMB calculation method was developed at IC (IC algorithm) and compared to the FoundationOne® (FO) algorithm. Using IC algorithm, an optimal 10% variant allele frequency (VAF) cut-off was established for TMB evaluation on FFPE samples, compared to 5% on frozen samples. The median TMB score for MSS/POLE WT tumors was 8.8 mut/Mb versus 45 mut/Mb for MSI/POLE-mutated tumors. When focusing on MSS/POLE WT tumor samples, the highest median TMB scores were observed in lymphoma, lung, endometrial, and cervical cancers. After biological manual curation of these cases, 21% of them could be reclassified as MSI/POLE tumors and considered as "true TMB high." Higher TMB values were obtained using FO algorithm on FFPE samples compared to IC algorithm (40 mut/Mb [10-3927] versus 8.2 mut/Mb [2.5-897], p < 0.001). CONCLUSIONS: We herein propose a TMB calculation method and a bioinformatics tool that is customizable to different NGS panels and sample types. We were not able to retrieve TMB values from FO algorithm using our own algorithm and NGS panel.
Subject(s)
Neoplasms , Humans , Mutation , Neoplasms/genetics , High-Throughput Nucleotide Sequencing/methodsABSTRACT
BACKGROUND: The MSH3 gene is part of the DNA mismatch repair system, but has never been shown to be involved in Lynch syndrome. A first report of four patients from two families, bearing biallelic MSH3 germline variants, with a phenotype of attenuated colorectal adenomatous polyposis raised the question of its involvement in hereditary cancer predisposition. The patients' tumours exhibited elevated microsatellite alterations at selected tetranucleotide repeats (EMAST), a hallmark of MSH3 deficiency. METHODS: We report five new unrelated patients with MSH3-associated polyposis. We describe their personal and familial history and study the EMAST phenotype in various normal and tumour samples, which are relevant findings based on the rarity of this polyposis subtype so far. RESULTS: All patients had attenuated colorectal adenomatous polyposis, with duodenal polyposis in two cases. Both women had breast carcinomas. EMAST phenotype was present at various levels in different samples of the five patients, confirming the MSH3 deficiency, with a gradient of instability in polyps depending on their degree of dysplasia. The negative EMAST phenotype ruled out the diagnosis of germline MSH3 deficiency for two patients: one homozygous for a benign variant and one with a monoallelic large deletion. CONCLUSION: This report lends further credence to biallelic MSH3 germline pathogenic variants being involved in colorectal and duodenal adenomatous polyposis. Large-scale studies may help clarify the tumour spectrum and associated risks. Ascertainment of EMAST may help with the interpretation of variants of unknown significance. We recommend adding MSH3 to dedicated diagnostic gene panels.
Subject(s)
Adenomatous Polyposis Coli , Colorectal Neoplasms, Hereditary Nonpolyposis , Colorectal Neoplasms , Humans , Female , Adenomatous Polyposis Coli/genetics , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Microsatellite Repeats/genetics , Colorectal Neoplasms, Hereditary Nonpolyposis/genetics , Genetic Predisposition to Disease , MutS Homolog 3 Protein/genetics , MutS Homolog 3 Protein/metabolismABSTRACT
In breast or ovarian cancer (BC/OC) patients with evocative personal and/or family history, multigene panel sequencing is performed on blood to diagnose hereditary predispositions. Additionally, BRCA1/BRCA2 testing can be performed on tumor sample for therapeutic purpose. The accuracy of multigene panel tumor analysis on BC/OC to detect predisposing germline pathogenic variants (gPV) has not been precisely assessed. By comparing sequencing data from blood and fresh-frozen tumor we show that tumor genomic instability causes pitfalls to consider when performing tumor testing to detect gPV. Even if loss of heterozygosity increases germline signal in most cases, somatic copy number variants (CNV) can mask germline CNV and collapse point gPV variant allele frequency (VAF). Moreover, VAF does not allow an accurate distinction between germline and somatic pathogenic variants.
Subject(s)
Breast Neoplasms , Ovarian Neoplasms , Female , Humans , Genetic Predisposition to Disease , Ovarian Neoplasms/diagnosis , Ovarian Neoplasms/genetics , BRCA1 Protein/genetics , BRCA2 Protein/genetics , Genes, BRCA2 , Breast Neoplasms/diagnosis , Breast Neoplasms/genetics , Germ-Line Mutation/geneticsABSTRACT
First-line therapy in advanced non-small-cell-lung-cancer (NSCLC) is based on chemotherapy except for patients with a tumor proportion score for programmed death ligand 1 (PD-L1) of 50% or greater, pembrolizumab is administrated. However, patients with somatic-EGFR-mutated tumors had usually been excluded from clinical applications of immune checkpoint inhibitors (ICIs). Germline-EGFR-mutated-patients are known to not respond to EGFR-Tyrosine-Kinase-inhibitors (TKIs). But what about germline EGFR mutations and response to ICIs? Herein, we describe the case of a long response to ICIs treatment in a complex metastatic NSCLC with co-occuring EGFR germline and KRAS somatic mutations, high PD-L1 score and a smoking history.
Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , B7-H1 Antigen/genetics , Immune Checkpoint Inhibitors/therapeutic use , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Germ-Line Mutation , ErbB Receptors/genetics , Mutation , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathologyABSTRACT
The clinical actionability of circulating tumor DNA requires sensitive detection methods with a short turnaround time. In the PADA-1 phase 3 trial (NCT03079011), metastatic breast cancer patients treated with an aromatase inhibitor and palbociclib were screened every 2 months for activating ESR1 mutations in blood (bESR1mut). We report the feasibility of the droplet digital polymerase chain reaction (ddPCR) and cross-validation with next-generation sequencing (NGS). bESR1mut testing was centralized in two platforms using the same ddPCR assay. Results were reported as copies/mL of plasma and mutant allele frequency (MAF). We analyzed 200 positive ddPCR samples with an NGS assay (0.5-1% sensitivity). Overall, 12,552 blood samples were collected from 1017 patients from 83 centers. Among the 12,525 available samples with ddPCR results, 11,533 (92%) were bESR1mut-negative. A total of 267 patients newly displayed bESR1mut (26% patients/2% samples) with a median copy number of 14/mL (range: 4-1225) and a median MAF of 0.83% (0.11-35), 648 samples (20% patients/5% samples) displayed persistent bESR1mut, and 77 (<1%) samples encountered a technical failure. The median turnaround time from blood drawing to result notification was 13 days (Q1:9; Q3:21 days). Among 200 ddPCR-positive samples tested, NGS detected bESR1mut in 168 (84%); 25 of the 32 cases missed by NGS had low MAF and/or low coverage. In these 200 samples, bESR1mut MAF by both techniques had an excellent intraclass correlation coefficient (ICC = 0.93; 95% CI [0.85; 0.97]). These results from a large-scale trial support the feasibility and accuracy of real-time bESR1mut tracking by ddPCR, opening new opportunities for therapeutic interventions.
Subject(s)
Circulating Tumor DNA , High-Throughput Nucleotide Sequencing , Feasibility Studies , High-Throughput Nucleotide Sequencing/methods , Humans , Mutation , Polymerase Chain Reaction/methodsABSTRACT
INTRODUCTION: About 2-3% of non-small-cell lung cancers (NSCLCs) harbor MET exon-14-skipping (METex14) mutations. Efficacy of the MET-inhibitor crizotinib has been reported, but progression-free survival (PFS) was very short. Immune-checkpoint inhibitors (ICIs) have become a cornerstone of NSCLC treatment but appear to be less effective in non-smokers and against tumors exhibiting oncogenic addiction. We describe 6 remarkable (PFS exceeding 18 months) and durable responses to ICIs of NSCLCs harboring a METex14 mutation. METHODS: Each patient's clinical and biological characteristics, and tumor responses after ICIs were examined. Complete tumor-DNA sequencing was available after starting second-line ICIs, which followed first-line chemotherapy. Tumor-cell programmed cell-death protein-1 ligand-1 (PD-L1) expression on tumor cells was evaluated using antibody clone E1L3N (Cell Signaling Technology). RESULTS: Among 25 patients with METex14-mutated NSCLCs, 13 of whom were ICI-treated, 6 had prolonged responses: 5 women, 1 man; 57-80 years old; 3 never-smokers, 1 ex-smoker and 2 smokers; 5 adenocarcinomas, 1 sarcomatoid carcinoma; 5 received nivolumab, 1 pembrolizumab. No EGFR, BRAF or KRAS mutations (only 1 minority KRAS mutation), or ALK or ROS translocations were detected. No concurrent MET amplification was observed. Tumor-mutation burden was low (<10 mutations/Mb) in 3 tested tumors. Four partial and 2 complete responses were obtained during the first 3 months for 5 patients, while pseudoprogression was initially observed in 1. Tolerance was excellent, with only 1 grade-3 immune-related adverse event. Response was maintained for 18-49 months. CONCLUSION: ICIs could be considered to treat patients whose NSCLCs harbor a METex14 mutation. More biological marker data are needed to identify which patients are most likely to benefit from ICIs.
Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Aged , Aged, 80 and over , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Exons , Female , Humans , Immunotherapy , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Male , Middle Aged , MutationABSTRACT
ESR1 mutation is frequently encountered in hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer (MBC), especially after aromatase inhibitor (AI) therapy, as a mechanism of resistance to endocrine therapy. Circulating tumor DNA-based detection of ESR1 mutation in plasma has been demonstrated as a prognostic and predictive factor for poor outcomes in subsequent AI therapy. In this case report, for the first time, we describe the detection of ESR1 mutation (p.Tyr537Ser) only in the cerebrospinal fluid (CSF) and not in the plasma of a patient with isolated leptomeningeal progression who was treated with AI for HR-positive, HER2-negative MBC (bone metastasis only). Circulating tumor DNA levels also appeared to be correlated with clinical evolution. We suggest that in the presence of isolated leptomeningeal metastasis and when tamoxifen or AI has been prescribed for HR-positive MBC, CSF should be screened for ESR1 mutations to potentially adjust systemic treatment.
ABSTRACT
BACKGROUND: Microsatellite instability (MSI) has recently emerged as a predictive pan-tumor biomarker of immunotherapy efficacy, stimulating the development of diagnostic tools compatible with large-scale screening of patients. In this context, noninvasive detection of MSI from circulating tumor DNA stands as a promising diagnostic and posttreatment monitoring tool. METHODS: We developed drop-off droplet-digital PCR (ddPCR) assays targeting BAT-26, activin A receptor type 2A (ACVR2A), and defensin beta 105A/B (DEFB105A/B) microsatellite markers. Performances of the assays were measured on reconstitution experiments of various mutant allelic fractions, on 185 tumor samples with known MSI status, and on 72 blood samples collected from 42 patients with advanced colorectal or endometrial cancers before and/or during therapy. RESULTS: The 3 ddPCR assays reached analytical sensitivity <0.1% variant allelic frequency and could reliably detect and quantify MSI in both tumor and body fluid samples. High concordance between MSI status determination by the three-marker ddPCR test and the reference pentaplex method were observed (100% for colorectal tumors and 93% for other tumor types). Moreover, the 3 assays showed correlations with r ≥ 0.99 with other circulating tumor DNA markers and their dynamic during treatment correlated well with clinical response. CONCLUSIONS: This innovative approach for MSI detection provides a noninvasive, cost-effective, and fast diagnostic tool, well suited for large-scale screening of patients that may benefit from immunotherapy agents, as well as for monitoring treatment responses.
Subject(s)
Colorectal Neoplasms/genetics , Endometrial Neoplasms/genetics , Liquid Biopsy , Microsatellite Instability , Polymerase Chain Reaction/methods , Activin Receptors, Type II/genetics , Biomarkers, Tumor , Cell Line, Tumor , Circulating Tumor DNA/blood , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/pathology , Endometrial Neoplasms/drug therapy , Endometrial Neoplasms/pathology , False Positive Reactions , Female , Genetic Markers , Humans , Limit of Detection , Microsatellite Repeats , beta-Defensins/geneticsABSTRACT
Activating mutations in the estrogen receptor 1 (ESR1) gene confer resistance to aromatase inhibitors (AI), and may be targeted by selective estrogen receptor downregulators. We designed a multiplex droplet digital PCR (ddPCR), which combines a drop-off assay, targeting the clustered hotspot mutations found in exon 8, with an unconventional assay interrogating the E380Q mutation in exon 5. We assessed its sensitivity in vitro using synthetic oligonucleotides, harboring E380Q, L536R, Y537C, Y537N, Y537S, or D538G mutations. Further validation was performed on plasma samples from a prospective study and compared with next generation sequencing (NGS) data. The multiplex ESR1-ddPCR showed a high sensitivity with a limit of detection ranging from 0.07 to 0.19% in mutant allele frequency. The screening of plasma samples from patients with AI-resistant metastatic breast cancer identified ESR1 mutations in 29% of them, all mutations being confirmed by NGS. In addition, this test identifies patients harboring polyclonal alterations. Furthermore, the monitoring of circulating tumor DNA using this technique during treatment follow-up predicts the clinical benefit of palbociclib-fulvestrant. The multiplex ESR1-ddPCR detects, in a single reaction, the most frequent ESR1 activating mutations with good sensitivity. This method allows real-time liquid biopsy for ESR1 mutation monitoring in large cohorts of patients.
Subject(s)
Estrogen Receptor alpha/genetics , Mutation/genetics , Plasma/chemistry , Polymerase Chain Reaction/methods , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Circulating Tumor DNA , Exons/genetics , Female , Fulvestrant/pharmacology , Gene Frequency/genetics , Humans , Piperazines/pharmacology , Prospective Studies , Pyridines/pharmacologyABSTRACT
Luminal androgen receptor (LAR) breast cancer accounts for 10% of all triple-negative breast cancers (TNBC). Anti-androgen therapy for this subtype is in development, but yields only partial clinical benefits. In this study, we aimed to characterize the genomic alterations of LAR TNBC, to analyze activation of the PI3K signaling pathway and to compare the response to PI3K pathway inhibitors with that to anti-androgen therapy in patient-derived xenografts (PDX) of LAR TNBC. Methods: Four LAR PDX models were identified, on the basis of their transcriptomic profiles, in a cohort of 57 PDX models of TNBC. The expression of AR-related genes, basal and luminal cytokeratins and EMT genes was analyzed by RT-PCR and IHC. AKT1 and PIK3CA mutations were identified by targeted NGS, and activation of the PI3K pathway was analyzed with a reverse-phase protein array. Three LAR PDXs with a PIK3CA or AKT1 mutation were treated with the AR inhibitor enzalutamide, a PI3K inhibitor, a dual PI3K-mTOR inhibitor and a mTORC1-mTORC2 inhibitor. Finally, we screened a clinical cohort of 329 TNBC for PIK3CA and AKT1 hotspot mutations. Results: LAR TNBC PDXs were significantly enriched in PIK3CA and AKT1 mutations, and had higher levels of luminal-androgen-like gene expression and a higher PI3K pathway protein activation score than other TNBC subtypes. Immunohistochemistry analysis revealed strong expression of the luminal cytokeratin CK18 and AR in three LAR PDX models. We found that mTOR and PI3K inhibitors had marked antitumor activity in vivo in PDX harboring genomic alterations of PIK3CA and AKT1 genes that did not respond to the AR antagonist enzalutamide. PIK3CA mutations were detected in more than one third of AR+ TNBC from patients (38%), and only 10% of AR-negative TNBC. Conclusion: Our results for PDX models of LAR TNBC resistant to enzalutamide indicate that PIK3CA and AKT1 are potential therapeutic targets.
Subject(s)
Heterografts/drug effects , Receptors, Androgen/genetics , TOR Serine-Threonine Kinases/antagonists & inhibitors , Triple Negative Breast Neoplasms/genetics , Adult , Aged , Aged, 80 and over , Benzamides , Drug Resistance, Neoplasm/genetics , Female , Humans , Middle Aged , Molecular Targeted Therapy/methods , Mutation , Nitriles , Phenylthiohydantoin/analogs & derivatives , Phenylthiohydantoin/pharmacology , Phenylthiohydantoin/therapeutic use , Phosphoinositide-3 Kinase Inhibitors/therapeutic use , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use , Receptors, Androgen/drug effects , Signal Transduction/genetics , TOR Serine-Threonine Kinases/metabolism , Triple Negative Breast Neoplasms/pathologyABSTRACT
OBJECTIVES: T790M mutations inEGFR-mutated non-small cell lung cancer (NSCLC) account for nearly 50% of acquired resistance mechanisms to EGFR-TKIs. Earlier studies suggested that tumor T790M could also be detected in TKI-naïve EGFR-mutated NSCLC. The aim of the study is to assess the prevalence and clinical significance of quantification of tumor pre-treatment T790M subclones. MATERIALS AND METHODS: We analyzed 366 EGFR-mutated NSCLC patients of the real-life IFCT Biomarkers France study with available pre-treatment formalin-fixed paraffin-embedded (FFPE) tumor DNA before treatment by first/second-generation EGFR-TKI. We used ultra-sensitive Droplet Digital Polymerase Chain Reaction (ddPCR) QX200 (BIO-RAD®, Hercules, CA, USA). All samples were tested in duplicate. RESULTS: ddPCR identified T790M in 19/240 specimens (8%). T790M-positive and T790M-negative populations were not different for clinical baseline characteristics. T790M Variant Allele Frequency (VAF) was > 0.01% <0.1%, > 0.1% <1%, > 1% <10%, and >10% in five (26.3%), six (31.6%), six (31.6%), and two (10.5%) patients, respectively. T790M VAF was >0.1% in 11/13 (84%) patients with rapid (<3 months) or usual progression (3-20 months) compared to 0/3 with low progression (>20 months) (p = 0.02). In a Cox model, T790M mutation positivity was correlated with overall survival (OS) and progression-free survival (PFS) for 10% > VAF >1% (hazard ratio [HR] = 2.83, 95% confidence interval [CI] 1.13-7.07, p = 0.03; HR=3.62, 95%CI 1.43-4.92, p = 0.007, respectively) and for VAF >10% (HR = 19.14, 95%CI 4.35-84.26, p < 0.001; HR = 17.89, 95%CI 2.21-144.86, p = 0.007, respectively). CONCLUSION: Ultra-sensitive detection of tumor T790M mutation concerned 8% of EGFR-mutated TKI-naïve NSCLC patients and has a negative prognostic value only for T790M VAF over 1%.
Subject(s)
Carcinoma, Non-Small-Cell Lung/pathology , Lung Neoplasms/pathology , Mutation , Protein Kinase Inhibitors/therapeutic use , Adenocarcinoma of Lung/drug therapy , Adenocarcinoma of Lung/genetics , Adenocarcinoma of Lung/pathology , Adult , Aged , Aged, 80 and over , Biomarkers, Tumor/genetics , Carcinoma, Large Cell/drug therapy , Carcinoma, Large Cell/genetics , Carcinoma, Large Cell/pathology , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Squamous Cell/drug therapy , Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/pathology , Drug Resistance, Neoplasm , ErbB Receptors/genetics , Female , Follow-Up Studies , France , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Male , Middle Aged , Prognosis , Retrospective Studies , Survival RateABSTRACT
INTRODUCTION: MET proto-oncogene (MET) exon 14 splice site (METex14) mutations were recently described in NSCLC and has been reported to correlate with efficacy of MET tyrosine kinase inhibitors. High diversity of these alterations makes them hard to detect by DNA sequencing in clinical practice. Because METex14 mutations induce increased stabilization of the MET receptor, it is anticipated that these mutations are associated with MET overexpression. We aim to determine whether NSCLC with high MET overexpression could define a subset of patients with a high rate of METex14 mutations. METHODS: From The French Cooperative Thoracic Intergroup PREDICT.amm cohort of 843 consecutive patients with a treatment-naive advanced NSCLC who were eligible for a first-line therapy, 108 NSCLC samples with high MET overexpression defined by an immunochemistry score 3+ were tested for METex14 mutations using fragment length analysis combined with optimized targeted next-generation sequencing. MET copy number analysis was also derived from the sequencing data. RESULTS: METex14 mutations were detected in two patients (2.2%) who also displayed a TP53 mutation and a PIK3CA mutation, respectively. An MET gene copy number increase was observed in seven additional patients (7.7%). Next-generation sequencing analysis revealed inactivating mutations in TP53 (52.7%) and PTEN (1.1%), and oncogenic mutations in KRAS (28.6%), EGFR (7.7%), PIK3CA (4.4%), BRAF (4.4%), NRAS (2.2%), GNAS (1.1%), and IDH1 (1.1%). CONCLUSIONS: The rate of METex14 mutations in NSCLC with high MET overexpression was similar to that found in unselected NSCLC. Moreover, we observed a high frequency of driver alterations in other oncogenes. Consequently these findings do not support the use of MET immunohistochemistry as a surrogate marker for METex14 mutations.
Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Carcinoma, Non-Small-Cell Lung/genetics , Exons/genetics , Humans , Lung Neoplasms/genetics , Mutation , Proto-Oncogene Mas , Proto-Oncogene Proteins c-met/geneticsABSTRACT
HER3, a member of the EGFR family of receptor tyrosine kinases coded by the ERBB3 gene, plays an important role in cancer, despite its lack of intrinsic kinase activity. As with genes coding for potential heterodimeric partners of HER3, EGFR, and HER2, oncogenic mutations of ERBB3 have been explored by several studies. In this review, we discuss the evidence presenting ERBB3 somatic mutations as potential tumoral drivers. We then show that ERBB3 mutations are not uncommon in many cancer types. Finally, we present the recent results of several studies evaluating different therapeutic approaches for treating patients with oncogenic ERBB3 mutations.
Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacology , Carcinogenesis/genetics , Neoplasms/drug therapy , Protein Kinase Inhibitors/pharmacology , Receptor, ErbB-3/genetics , Animals , Antibodies, Monoclonal/pharmacology , Antibodies, Monoclonal/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinogenesis/drug effects , Cell Line, Tumor , Clinical Trials as Topic , Humans , Mice , Molecular Targeted Therapy/methods , Mutation , Neoplasms/genetics , Neoplasms/mortality , Neoplasms/pathology , Progression-Free Survival , Protein Kinase Inhibitors/therapeutic use , Protein Multimerization/drug effects , Protein Multimerization/genetics , Receptor, ErbB-2/antagonists & inhibitors , Receptor, ErbB-2/genetics , Receptor, ErbB-2/metabolism , Receptor, ErbB-3/antagonists & inhibitors , Receptor, ErbB-3/metabolism , Signal Transduction/drug effects , Signal Transduction/genetics , Treatment Outcome , Xenograft Model Antitumor AssaysABSTRACT
Introduction: In hormone receptor-positive breast cancer, ESR1 mutations have emerged as a key mechanism of resistance to endocrine therapy. Areas covered: Here, we review currently available data on ESR1 mutations, regarding their functional impact, prevalence at different stages (and according to the material used: tissue-based analysis vs. liquid biopsy), prognostic impact and predictive value of resistance to aromatase inhibitors. Possible strategies to overcome this resistance by using selective estrogen receptor downregulators (such as fulvestrant) are also discussed. Expert opinion: ESR1 mutation detection will probably become a prognostic and predictive biomarker in the future, used in clinical practice for hormone-receptor breast cancer, especially in the metastatic setting. In the future, we should expect to assess ESR1 mutations, using liquid biopsy (by digital-PCR or next-generation sequencing), in the same way as other prognostic or predictive biomarkers, such as EGFR mutations in lung cancer, and possibly even have targeted-therapies against these mutations.
Subject(s)
Biomarkers, Tumor , Breast Neoplasms/genetics , Estrogen Receptor alpha/genetics , Mutation , Antineoplastic Agents, Immunological/pharmacology , Antineoplastic Agents, Immunological/therapeutic use , Breast Neoplasms/diagnosis , Breast Neoplasms/therapy , DNA Mutational Analysis , Drug Discovery , Drug Resistance, Neoplasm , Estrogen Receptor alpha/chemistry , Estrogen Receptor alpha/metabolism , Expert Testimony , Female , Genetic Testing , Genetic Variation , Humans , Molecular Targeted Therapy , Prognosis , Structure-Activity Relationship , Treatment OutcomeABSTRACT
Triple-negative breast cancer (TNBC) represents 10% of all breast cancers and is a very heterogeneous disease. Globally, women with TNBC have a poor prognosis, and the development of effective targeted therapies remains a real challenge. Patient-derived xenografts (PDX) are clinically relevant models that have emerged as important tools for the analysis of drug activity and predictive biomarker discovery. The purpose of this work was to analyze the molecular heterogeneity of a large panel of TNBC PDX (n = 61) in order to test targeted therapies and identify biomarkers of response. At the gene expression level, TNBC PDX represent all of the various TNBC subtypes identified by the Lehmann classification except for immunomodulatory subtype, which is underrepresented in PDX. NGS and copy number data showed a similar diversity of significantly mutated gene and somatic copy number alteration in PDX and the Cancer Genome Atlas TNBC patients. The genes most commonly altered were TP53 and oncogenes and tumor suppressors of the PI3K/AKT/mTOR and MAPK pathways. PDX showed similar morphology and immunohistochemistry markers to those of the original tumors. Efficacy experiments with PI3K and MAPK inhibitor monotherapy or combination therapy showed an antitumor activity in PDX carrying genomic mutations of PIK3CA and NRAS genes. TNBC PDX reproduce the molecular heterogeneity of TNBC patients. This large collection of PDX is a clinically relevant platform for drug testing, biomarker discovery and translational research.
Subject(s)
Gene Dosage , Gene Expression Profiling/methods , Gene Regulatory Networks , High-Throughput Nucleotide Sequencing/methods , Triple Negative Breast Neoplasms/genetics , Animals , Class I Phosphatidylinositol 3-Kinases/genetics , Female , GTP Phosphohydrolases/genetics , Gene Expression Regulation, Neoplastic , Genetic Heterogeneity , Humans , Membrane Proteins/genetics , Mice , Middle Aged , Molecular Targeted Therapy , Neoplasm Transplantation , Precision Medicine , Signal Transduction , Triple Negative Breast Neoplasms/drug therapy , Triple Negative Breast Neoplasms/pathology , Tumor Suppressor Protein p53/geneticsABSTRACT
INTRODUCTION: Evaluation of EGFR Mutation status for the administration of EGFR-TKIs in non-small cell lung Carcinoma (ERMETIC) was a prospective study designed to validate the prognostic value of EGFR/KRAS mutations in patients with advanced non-small-cell lung cancer (NSCLC), all receiving a first-generation tyrosine kinase inhibitor, erlotinib. ERMETIC2 was an ancillary project evaluating the clinical value of common EGFR/KRAS-mutated subclones regarding prognosis using highly sensitive molecular detection methods. MATERIALS AND METHODS: Tumor samples from 228 patients with NSCLC (59% adenocarcinoma, 37% women, and 19% never/former smokers) were available for reanalysis using alternative highly sensitive molecular techniques. A multivariate Cox model was used for prognostic analysis. RESULTS: Using alternative highly sensitive techniques, 16 EGFR and 51 KRAS supplementary mutations were newly identified, all still exclusive, leading to an overall rate of 12.3% (n = 28) and 33.3% (n = 76), respectively. Using real-time polymerase chain reaction (hybridization probe), they were significantly associated with progression-free survival (P = .02) and overall survival (OS) (P = .01), which were better for EGFR-mutated patients for progression-free survival (hazard ratio [HR], 0.46; 95% confidence interval [CI], 0.28-0.78) and OS (HR, 0.56; 95% CI, 0.31-1), and worse for KRAS mutations and OS (HR, 1.63; 95% CI, 1.09-2.44). Using the most sensitive technique detection for KRAS-clamp polymerase chain reaction-KRAS mutated subclones did not impact OS. CONCLUSIONS: KRAS and EGFR mutations were detected in higher proportions by alternative highly sensitive molecular techniques compared with direct Sanger sequencing. However, minor KRAS-mutated subclones offered no prognostic value when representing less than 1% of the tumor cells.
Subject(s)
Antineoplastic Agents/therapeutic use , Carcinoma, Non-Small-Cell Lung/genetics , Erlotinib Hydrochloride/therapeutic use , Lung Neoplasms/genetics , Aged , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/mortality , Cohort Studies , ErbB Receptors/genetics , Female , France , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/mortality , Male , Middle Aged , Mutation/genetics , Neoplasm Staging , Prospective Studies , Proto-Oncogene Proteins p21(ras)/genetics , Survival Analysis , Treatment OutcomeABSTRACT
BACKGROUND: High throughput molecular screening techniques allow the identification of multiple molecular alterations, some of which are actionable and can be targeted by molecularly targeted agents (MTA). We aimed at evaluating the relevance of using this approach in the frame of Institut Curie Molecular Tumor Board (MTB) to guide patients with cancer to clinical trials with MTAs. PATIENTS AND METHODS: We included all patients presented at Institut Curie MTB from 4 October 2014 to 31 October 2017. The following information was extracted from the chart: decision to perform tumour profiling, types of molecular analyses, samples used, molecular alterations identified and those which are actionable, and inclusion in a clinical trial with matched MTA. RESULTS: 736 patients were presented at the MTB. Molecular analyses were performed in 442 patients (60%). Techniques used included next-generation sequencing, comparative genomic hybridisation array and/or other techniques including immunohistochemistry in 78%, 51% and 58% of patients, respectively. Analyses were performed on a fresh frozen biopsy in 91 patients (21%), on archival tissue (fixed or frozen) in 326 patients (74%) and on both archival and fresh frozen biopsy in 25 patients (6%). At least one molecular alteration was identified in 280 analysed patients (63%). An actionable molecular alteration was identified in 207 analysed patients (47%). Forty-five analysed patients (10%) were enrolled in a clinical trial with matched MTA and 29 additional patients were oriented and included in a clinical trial based on a molecular alteration identified prior to the MTB analysis. Median time between date of specimen reception and molecular results was 28 days (range: 5-168). CONCLUSIONS: The implementation of an MTB at Institut Curie enabled the inclusion of 10% of patients into a clinical trial with matched therapy.
ABSTRACT
Neuroendocrine breast carcinomas represent a rare subtype of breast cancer. Their definition, prevalence, and prognosis remain controversial in the literature. The 2012 WHO classification of breast cancer categorizes neuroendocrine carcinomas into three morphologically distinct subtypes: well-differentiated neuroendocrine tumors, poorly differentiated neuroendocrine carcinomas, and invasive breast carcinomas with neuroendocrine differentiation. We aimed to gain insight into the clinical, morphologic, phenotypic, and molecular features of 47 neuroendocrine breast carcinomas. Targeted next-generation sequencing by an AmpliSeq 22 cancer gene hotspot panel and the Prosigna assay were performed on 42/47 and 35/47 cases, respectively. Average age at diagnosis was 69 years. All tumors were estrogen receptor-positive and the large majority expressed progesterone receptor (89%), GATA3 (98%), FOXA1 (96%), and CK8/18 (98%). There was an almost equal distribution of luminal A (52%) and B (48%) carcinomas. Almost half of the cohort (49%) displayed a high risk of recurrence score with the Prosigna test. Patients with a neuroendocrine carcinoma had a shorter disease-free survival compared with those affected by carcinomas of no special type matched for age, size, grade, and estrogen receptor status. No significant differences were observed in terms of overall survival. Stratification of neuroendocrine carcinomas using the 2012 WHO criteria did not reveal statistically significant differences among the distinct categories (well-differentiated neuroendocrine tumors, poorly differentiated neuroendocrine carcinomas, and invasive breast carcinomas with neuroendocrine differentiation), in terms of either progression-free or overall survival. Our targeted sequencing analysis found three cases (7%) harboring a PIK3CA mutation, and in three other cases (7%) TP53 mutations were detected. This study showed that neuroendocrine breast carcinoma is a distinct subtype of luminal carcinoma with a low rate of PIK3CA mutations and with an aggressive clinical behavior. An accurate identification of neuroendocrine differentiation may be useful to better tailor patient adjuvant therapy within luminal carcinomas.