Colon cancer (CC) pathological staging fails to accurately predict recurrence, and to date, no gene expression signature has proven reliable for prognosis stratification in clinical practice, perhaps ...because CC is a heterogeneous disease. The aim of this study was to establish a comprehensive molecular classification of CC based on mRNA expression profile analyses.
Fresh-frozen primary tumor samples from a large multicenter cohort of 750 patients with stage I to IV CC who underwent surgery between 1987 and 2007 in seven centers were characterized for common DNA alterations, including BRAF, KRAS, and TP53 mutations, CpG island methylator phenotype, mismatch repair status, and chromosomal instability status, and were screened with whole genome and transcriptome arrays. 566 samples fulfilled RNA quality requirements. Unsupervised consensus hierarchical clustering applied to gene expression data from a discovery subset of 443 CC samples identified six molecular subtypes. These subtypes were associated with distinct clinicopathological characteristics, molecular alterations, specific enrichments of supervised gene expression signatures (stem cell phenotype-like, normal-like, serrated CC phenotype-like), and deregulated signaling pathways. Based on their main biological characteristics, we distinguished a deficient mismatch repair subtype, a KRAS mutant subtype, a cancer stem cell subtype, and three chromosomal instability subtypes, including one associated with down-regulated immune pathways, one with up-regulation of the Wnt pathway, and one displaying a normal-like gene expression profile. The classification was validated in the remaining 123 samples plus an independent set of 1,058 CC samples, including eight public datasets. Furthermore, prognosis was analyzed in the subset of stage II-III CC samples. The subtypes C4 and C6, but not the subtypes C1, C2, C3, and C5, were independently associated with shorter relapse-free survival, even after adjusting for age, sex, stage, and the emerging prognostic classifier Oncotype DX Colon Cancer Assay recurrence score (hazard ratio 1.5, 95% CI 1.1-2.1, p = 0.0097). However, a limitation of this study is that information on tumor grade and number of nodes examined was not available.
We describe the first, to our knowledge, robust transcriptome-based classification of CC that improves the current disease stratification based on clinicopathological variables and common DNA markers. The biological relevance of these subtypes is illustrated by significant differences in prognosis. This analysis provides possibilities for improving prognostic models and therapeutic strategies. In conclusion, we report a new classification of CC into six molecular subtypes that arise through distinct biological pathways.
Despite fluoropyrimidines (FPs) constituting the main component of the chemotherapy combination protocols in 50% of chemotherapies for solid tumour treatments, incidence data for FP-related toxicity ...are poorly documented in real life. This study evaluated the number of patients receiving FP-based chemotherapies in France, along with the true incidence of FP-related serious adverse effects (SAEs) before the recent mandatory dihydropyrimidine dehydrogenase (DPD)-screening was introduced by French health authorities, DPD being the rate-limiting enzyme of 5-fluorouracil (5-FU) catabolism.
Exhaustive data on the number of patients treated with FP-based chemotherapy in 2013–2014 were collected in the Centre-Val de Loire region of France. True incidence of SAEs was extracted from a cohort of 513 patients with incident solid tumours receiving first-line FP-based chemotherapy.
After extrapolation at national level, we estimated that 76,200 patients are currently treated annually with 5FU (53,100 patients, 62% digestive system-related versus 26% breast cancers versus 12% head and neck cancers) or capecitabine (23,100 patients, 45% digestive system-related versus 37% breast cancers versus 18% non-documented). Earlier (in the first two cycles) the SAE incidence rate was 19.3% (95% confidence interval (CI) 16–23%) including one toxic death (0.2%, 95%CI 0–1%). SAE incidence rate was 32.2% (95%CI 28–36%) over the first 6 months of treatment. Incidence of death, life-threatening prognosis or incapacity/disability was 1.4% (95%CI 0.4–2.4%) and 1.6% (95%CI 0.5–2.6%) during first two cycles and first 6 months, respectively.
These data highlight the significant public health issue related to FP toxicity, with around 1200 patients developing FP-related life-threatening prognosis or incapacity/disability annually in France, including 150 toxic deaths. It is hoped that DPD-deficiency screening will reduce such iatrogenic events and eradicate toxic deaths.
•Early incidence rate of serious adverse events with fluoropyrimidines is 19.3%.•The number of FP-related toxic deaths is estimated around 150/year in France.•Death, life-threatening prognosis or incapacity affect 1200 patients/year in France.•These are declared to a pharmacovigilance centre in only 12.5% of cases.•Systematic pre-therapeutic screening of DPD deficiency is urgently needed.
Irinotecan is a major drug in the treatment of advanced colorectal cancer. Its active form is the SN38 metabolite, which is cleared by the biliary route after glucuronidation by uridine ...diphosphate–glucuronosyltransferase 1A1 (UGT1A1). UGT1A1 activity exhibits a wide intersubject variability, in part related to UGT1A1 gene polymorphisms. The present review on the impact of the deficient UGT1A1*28 variant on irinotecan efficacy and toxicity was produced by a French joint workgroup comprising the Group of Clinical Onco‐pharmacology (GPCO‐Unicancer) and the National Pharmacogenetics Network (RNPGx). It clearly emerges that for irinotecan doses at least equal to 180 mg/m2, patients homozygous for the UGT1A1*28 allele are at increased risk of developing hematological and/or digestive toxicities. Irinotecan dose reduction is thus recommended in homozygous *28/*28 patients. In addition, this personalized medicine strategy aims to secure high‐dose irinotecan administration (≥240 mg/m2) that have proven to be safe in homozygous *1/*1 patients only. The clinical relevance of this test is discussed in terms of treatment efficacy improvement, as increasing the irinotecan dose appears to be safe in patients not bearing a deficient allele. Best execution practices, cost‐effectiveness, and result interpretation are discussed with the aim of facilitating the implementation of this analysis in clinical practice. The existence of networks of laboratories performing this test in routine hospital treatment, as in France, offers the prospect of widespread screening, thus guaranteeing equal access to safe treatment and optimized therapy for patients receiving irinotecan‐based therapy in advanced colorectal cancer.
Fluourouracil (FU) is a mainstay of chemotherapy, although toxicities are common. Genetic biomarkers have been used to predict these adverse events, but their utility is uncertain.
We tested ...candidate polymorphisms identified from a systematic literature search for associations with capecitabine toxicity in 927 patients with colorectal cancer in the Quick and Simple and Reliable trial (QUASAR2). We then performed meta-analysis of QUASAR2 and 16 published studies (n = 4,855 patients) to examine the polymorphisms in various FU monotherapy and combination therapy regimens.
Global capecitabine toxicity (grades 0/1/2 v grades 3/4/5) was associated with the rare, functional DPYD alleles 2846T>A and *2A (combined odds ratio, 5.51; P = .0013) and with the common TYMS polymorphisms 5'VNTR2R/3R and 3'UTR 6bp ins-del (combined odds ratio, 1.31; P = 9.4 × 10(-6)). There was weaker evidence that these polymorphisms predict toxicity from bolus and infusional FU monotherapy. No good evidence of association with toxicity was found for the remaining polymorphisms, including several currently included in predictive kits. No polymorphisms were associated with toxicity in combination regimens.
A panel of genetic biomarkers for capecitabine monotherapy toxicity would currently comprise only the four DPYD and TYMS variants above. We estimate this test could provide 26% sensitivity, 86% specificity, and 49% positive predictive value-better than most available commercial kits, but suboptimal for clinical use. The test panel might be extended to include additional, rare DPYD variants functionally equivalent to *2A and 2846A, though insufficient evidence supports its use in bolus, infusional, or combination FU. There remains a need to identify further markers of FU toxicity for all regimens.
Aims
Determining dihydropyrimidine dehydrogenase (DPD) activity by measuring patient's uracil (U) plasma concentration is mandatory before fluoropyrimidine (FP) administration in France. In this ...study, we aimed to refine the pre‐analytical recommendations for determining U and dihydrouracil (UH2) concentrations, as they are essential in reliable DPD‐deficiency testing.
Methods
U and UH2 concentrations were collected from 14 hospital laboratories. Stability in whole blood and plasma after centrifugation, the type of anticoagulant and long‐term plasma storage were evaluated. The variation induced by time and temperature was calculated and compared to an acceptability range of ±20%. Inter‐occasion variability (IOV) of U and UH2 was assessed in 573 patients double sampled for DPD‐deficiency testing.
Results
Storage of blood samples before centrifugation at room temperature (RT) should not exceed 1 h, whereas cold (+4°C) storage maintains the stability of uracil after 5 hours. For patients correctly double sampled, IOV of U reached 22.4% for U (SD = 17.9%, range = 0–99%). Notably, 17% of them were assigned with a different phenotype (normal or DPD‐deficient) based on the analysis of their two samples. For those having at least one non‐compliant sample, this percentage increased up to 33.8%. The moment of blood collection did not affect the DPD phenotyping result.
Conclusion
Caution should be taken when interpreting U concentrations if the time before centrifugation exceeds 1 hour at RT, since it rises significantly afterwards. Not respecting the pre‐analytical conditions for DPD phenotyping increases the risk of DPD status misclassification.
Deficiency in dihydropyrimidine dehydrogenase (DPD) enzyme is the main cause of severe and lethal fluoropyrimidine-related toxicity. Various approaches have been developed for DPD-deficiency ...screening, including DPYD genotyping and phenotyping. The goal of this prospective observational study was to perform exhaustive exome DPYD sequencing and to examine relationships between DPYD variants and toxicity in advanced breast cancer patients receiving capecitabine.
Two-hundred forty-three patients were analysed (88.5% capecitabine monotherapy). Grade 3 and grade 4 capecitabine-related digestive and/or neurologic and/or hemato-toxicities were observed in 10.3% and 2.1% of patients, respectively. DPYD exome, along with flanking intronic regions 3'UTR and 5'UTR, were sequenced on MiSeq Illumina. DPD phenotype was assessed by pre-treatment plasma uracil (U) and dihydrouracil (UH2) measurement.
Among the 48 SNPs identified, 19 were located in coding regions, including 3 novel variations, each observed in a single patient (among which, F100L and A26T, both pathogenic in silico). Combined analysis of deleterious variants *2A, I560S (*13) and D949V showed significant association with grade 3-4 toxicity (sensitivity 16.7%, positive predictive value (PPV) 71.4%, relative risk (RR) 6.7, p<0.001) but not with grade 4 toxicity. Considering additional deleterious coding variants D342G, S492L, R592W and F100L increased the sensitivity to 26.7% for grade 3-4 toxicity (PPV 72.7%, RR 7.6, p<0.001), and was significantly associated with grade 4 toxicity (sensitivity 60%, PPV 27.3%, RR 31.4, p = 0.001), suggesting the clinical relevance of extended targeted DPYD genotyping. As compared to extended genotype, combining genotyping (7 variants) and phenotyping (U>16 ng/ml) did not substantially increase the sensitivity, while impairing PPV and RR.
Exploring an extended set of deleterious DPYD variants improves the performance of DPYD genotyping for predicting both grade 3-4 and grade 4 toxicities (digestive and/or neurologic and/or hematotoxicities) related to capecitabine, as compared to conventional genotyping restricted to consensual variants *2A, *13 and D949V.
Clinical data on salvage chemotherapy used after checkpoints inhibitors in oncology are reviewed, with a special focus on recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC).
...Converging evidence is emerging about high response and/or disease control rates associated with salvage chemotherapy after immunotherapy failure in advanced solid tumours. This phenomenon is mainly reported in retrospective studies for "hot tumours" such as R/M HNSCC, melanoma, lung, urothelial or gastric cancers, but also in haematological malignancies. Some physiopathological hypotheses have been raised.
Several independent series show increased response rates associated with postimmuno chemotherapy when compared with retrospective series in similar settings. Several mechanisms could be involved such as a "carry-over" allowed by a persistence of the checkpoint inhibitor, a modulation of tumour microenvironment components but also an intrinsic immunomodulatory effect of chemotherapy, increased by a specific immunologic state induced by the therapeutic pressure of checkpoint inhibitors. These data establish a rationale for prospectively evaluating the features of postimmunotherapy salvage chemotherapy.
Nucleotide excision repair (NER) modulates platinum-based chemotherapeutic efficacy by removing drug-produced DNA damage. To summarize published data on the association between polymorphisms of NER ...genes (ERCC1 and ERCC2) and responses to oxaliplatin-based chemotherapies, we carried out a meta-analysis of gastric and colorectal cancer for commonly studied polymorphisms ERCC1 rs11615C>T and ERCC2 rs13181T>G.
In 17 previously published studies, 1,787 cancer patients were treated with the oxaliplatin-based regimen. Primary outcomes included therapeutic response (TR; i.e., complete response + partial response vs. stable disease + progressive disease), progression-free survival (PFS), and overall survival (OS). We calculated OR or HR with 95% CIs to estimate the risk or hazard.
We found consistent and clinically substantial risk or hazard for TR, PFS, and OS in the oxaliplatin-treated gastric and colorectal cancer patients with an ethnic discrepancy. For ERCC1 rs11615C>T, the T allele was associated with reduced response and poor PFS and OS in Asians (TR: OR = 0.53 and 95% CI = 0.35-0.81; PFS: HR = 1.69 and 95% CI = 1.05-2.70; and OS: HR = 2.03 and 95% CI = 1.60-2.59). For ERCC2 rs13181T>G, the G allele was associated with reduced response and poor PFS and OS in Caucasians (TR: OR = 0.56 and 95% CI = 0.35-0.88; PFS: HR = 1.41 and 95% CI = 1.02-1.95; and OS: HR = 1.42 and 95% CI = 1.11-1.81).
NER ERCC1 rs11615C>T and ERCC2 rs13181T>G polymorphisms are useful prognostic factors in oxaliplatin-based treatment of gastric and colorectal cancer. Larger studies and further clinical trials are warranted to confirm these findings.
Objectives/Hypothesis
Recent preclinical and clinical studies on head and neck squamous cell carcinoma (HNSCC) revealed synergistic effects when combining anti‐EGFR agents with conventional ...chemotherapeutic drugs. Activation of the PI3‐kinase/AKT/mTOR signaling pathway has been identified as an important mechanism implicated in tumor progression and resistance to EGFR inhibitors. The aim of this study was to investigate the effects of combining the mTOR inhibitor temsirolimus (Tem) with the anti‐EGFR agent cetuximab (Cet) and conventional chemotherapeutic drugs (cisplatin and fluorouracil (C/F)) on an orthotopic model of HNSCC.
Study Design
Preclinical in vivo study.
Methods
We evaluated the anti‐tumor efficacy (measured tumor volume) of Tem, Cet, and C/F, administered alone or in combination. Investigations were performed using a human HNSCC cell line, CAL33, injected into the mouth floor of nude mice.
Results
As compared with the control, the combination of Tem and Cet led to the highest tumor inhibition and induced almost complete tumor growth arrest (P = 0.001). Tem significantly enhanced the impact of the Cet‐C/F combination on tumor growth (P < 0.001). The highest inhibitory effects of treatments on cell proliferation (Ki67 labeling), MAPK (pP42/44 labeling), and PI3K/AKT/mTOR (pS6R labeling) signaling pathways were found with the Tem‐Cet association.
Conclusion
In this orthotopic HNSCC model, the combination of Tem with Cet produced synergistic effects on tumor growth. These results were corroborated by a strong inhibition of both MAPK and PI3K‐mTOR signaling pathways.
Level of Evidence
N/A. Laryngoscope, 126:E156–E163, 2016
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