Utility of CYP2D6 copy number variants as prognostic biomarker in localized anal squamous cell carcinoma.

BACKGROUND: Anal squamous cell carcinoma (ASCC) is an infrequent tumor whose treatment has not changed since the 1970s. The aim of this study is the identification of biomarkers allowing personalized treatments and improvement of therapeutic outcomes. METHODS: Forty-six paraffin tumor samples from ASCC patients were analyzed by whole-exome sequencing. Copy number variants (CNVs) were identified and their relation to disease-free survival (DFS) was studied and validated in an independent retrospective cohort of 101 ASCC patients from the Multidisciplinary Spanish Digestive Cancer Group (GEMCAD). GEMCAD cohort proteomics allowed assessing the biological features of these tumors. RESULTS: On the discovery cohort, the median age was 61 years old, 50% were males, stages I/II/III: 3 (7%)/16 (35%)/27 (58%), respectively, median DFS was 33 months, and overall survival was 45 months. Twenty-nine genes whose duplication was related to DFS were identified. The most representative was duplications of the CYP2D locus, including CYP2D6, CYP2D7P, and CYP2D8P genes. Patients with CYP2D6 CNV had worse DFS at 5 years than those with two CYP2D6 copies (21% vs. 84%; p < .0002, hazard ratio [HR], 5.8; 95% confidence interval [CI], 2.7-24.9). In the GEMCAD validation cohort, patients with CYP2D6 CNV also had worse DFS at 5 years (56% vs. 87%; p = .02, HR = 3.6; 95% CI, 1.1-5.7). Mitochondria and mitochondrial cell-cycle proteins were overexpressed in patients with CYP2D6 CNV. CONCLUSIONS: Tumor CYP2D6 CNV identified patients with a significantly worse DFS at 5 years among localized ASCC patients treated with 5-fluorouracil, mitomycin C, and radiotherapy. Proteomics pointed out mitochondria and mitochondrial cell-cycle genes as possible therapeutic targets for these high-risk patients. PLAIN LANGUAGE SUMMARY: Anal squamous cell carcinoma is an infrequent tumor whose treatment has not been changed since the 1970s. However, disease-free survival in late staged tumors is between 40% and 70%. The presence of an alteration in the number of copies of CYP2D6 gene is a biomarker of worse disease-free survival. The analysis of the proteins in these high-risk patients pointed out mitochondria and mitochondrial cell-cycle genes as possible therapeutic targets. Therefore, the determination of the number of copies of CYP2D6 allows the identification of anal squamous carcinoma patients with a high-risk of relapse that could be redirected to a clinical trial. Additionally, this study may be useful to suggest new treatment strategies to increase current therapy efficacy.

Randomized phase II trial of FOLFIRI-panitumumab compared with FOLFIRI alone in patients with RAS wild-type circulating tumor DNA metastatic colorectal cancer beyond progression to first-line FOLFOX-panitumumab: the BEYOND study (GEMCAD 17-01).

PURPOSE: Panitumumab plus FOLFOX (P-FOLFOX) is standard first-line treatment for RAS wild-type (WT) metastatic colorectal cancer. The value of panitumumab rechallenge is currently unknown. We assessed addition of panitumumab to FOLFIRI (P-FOLFIRI) beyond progression to P-FOLFOX in patients with no RAS mutations in liquid biopsy (LB). METHODS: In this randomized phase II trial, patients were assigned (3:2 ratio) to second-line P-FOLFIRI (arm A) or FOLFIRI alone (arm B). LB for circulating tumor DNA analysis was collected at study entry and at disease progression. Primary endpoint was 6-month progression-free survival. Two-stage Simon design required 85 patients to be included (EudraCT 2017-004519-38). RESULTS: Between February 2019 and November 2020, 49 patients were screened (16 RAS mutations in LB detected) and 31 included (18 assigned to arm A and 13 to arm B). The study was prematurely closed due to inadequate recruitment. Serious adverse events were more frequent in arm A (44% vs. 23%). Overall response rate was 33% (arm A) vs. 7.7% (arm B). Six-month progression-free survival rate was 66.7% (arm A) and 38.5% (arm B). Median progression-free survival was 11.0 months (arm A) and 4.0 months (arm B) (hazard ratio, 0.58). At disease progression, RAS or BRAF mutations in LB were found in 4/11 patients (36%) in arm A and 2/10 (20%) in arm B. CONCLUSIONS: The BEYOND study suggests a meaningful benefit of P-FOLFIRI beyond progression to P-FOLFOX in metastatic colorectal cancer patients with WT RAS status selected by LB. This strategy deserves further investigation.

Is Metformin Associated With Improved Response to Neoadjuvant Chemoradiotherapy in Locally Advanced Rectal Cancer?

BACKGROUND: Efforts to determine whether metformin can increase the effectiveness of neoadjuvant chemoradiotherapy in rectal cancer have increased in recent years. However, retrospective studies have yielded inconclusive results. OBJECTIVES: The aim of this study was to compare oncological outcomes and survival after neoadjuvant chemoradiotherapy in patients with rectal cancer taking metformin versus in those not taking metformin. METHODS: This study analyzed 423 consecutive patients with locally advanced rectal cancer who underwent neoadjuvant chemoradiotherapy and curative surgery between January 2010 and May 2020; of these, 59 were taking metformin and 364 were not taking metformin. RESULTS: Patients taking metformin had a lower proportion of tumor regression (6.8% versus 22.0%, P = 0.012) as well as a lower proportion of patients achieving a pathological complete response (6.8% versus 20.6%, P = 0.011). In the multivariate analysis, independent predictors of pathologic complete response were not taking metformin (OR: 5.26, 95% CI: 1.12-24.85, P= 0.035) and cT2 stage (OR: 3.49, 95% CI: 1.10-11.07, P= 0.034); the interval was also an independent predictor of tumor regression (OR: 1.78, 95% CI: 1.06-2.96, P= 0.028). No differences were observed in survival between groups. CONCLUSION: Metformin was not associated with better tumor responses or survival after neoadjuvant treatment.

Delaying surgery by more than 10 weeks after long-course neoadjuvant radiotherapy in locally advanced rectal cancer patients improves pathologic complete response.

BACKGROUND: We currently do not know the optimal time interval between the end of chemoradiotherapy and surgery. Longer intervals have been associated with a higher pathological response rate, worse pathological outcomes and more morbidity. The aim of this study was to evaluate the effect and safety of the current trend of increasing time interval between the end of chemoradiotherapy and surgery (< 10 weeks vs. ≥ 10 weeks) on postoperative morbidity and pathological outcomes. This study analyzed 232 consecutive patients with locally advanced rectal cancer treated with long-course neoadjuvant chemoradiotherapy from January 2012 to August 2018. 125 patients underwent surgery before 10 weeks from the end of chemoradiotherapy (Group 1) and 107 patients underwent surgery after 10 or more weeks after the end of chemoradiotherapy (Group 2). Results have shown that wait for ≥ 10 weeks did not compromise surgical safety. Pathological complete response and tumor stage was statistically significant among groups. The effect of wait for ≥ 10 weeks before surgery shown higher tumor regression than the first group (Group 1, 12.8% vs Group 2, 31.8%; p < 0.001). On multivariate analysis, wait for ≥ 10 weeks was associated with pathological compete response. Patients from the second group were four time more likely to achieve pathologic complete response than patients from the first group (OR, 4.27 95%CI 1.60-11.40; p = 0.004). Patients who undergo surgery after ≥ 10 weeks of the end of chemoradiotherapy are four time more likely to achieve complete tumor remission without compromise surgical safety or postoperative morbidity.

Interferon/STAT1 and neuregulin signaling pathways are exploratory biomarkers of cetuximab (Erbitux®) efficacy in KRAS wild-type squamous carcinomas: a pathway-based analysis of whole human-genome microarray data from cetuximab-adapted tumor cell-line models.

KRAS mutation status is being used as the sole biomarker to predict therapeutic efficacy of cetuximab in metastatic colorectal cancer (mCRC). A significant number of mCRC patients with KRAS wild-type (WT) tumors, however, do not benefit from cetuximab. We are also lacking efficacy predictors in head and neck squamous cell carcinomas with an intact KRAS signaling and in non-small cell lung cancer in which KRAS mutations do not predict cetuximab efficacy. We recently established pre-clinical models of EGFR gene-amplified KRAS WT A431 squamous carcinoma cells chronically adapted to grow in the presence of cetuximab. We employed the ingenuity pathway analysis software to functionally interpret data from Agilent's whole human genome arrays in the context of biological processes, networks, and pathways. Cetuximab-induced activation of the interferon (IFN)/STAT1 appeared to switch from 'growth inhibitory' in acutely-treated cells to 'pro-survival' in chronically-adapted cells. Cetuximab treatment appeared to negatively select initially dominant IFN-sensitive clones and promoted selection of IFN- and cetuximab-refractory tumor clones constitutively bearing an up-regulated IFN/STAT1 signaling. High-levels of mRNAs coding for the EGFR ligands amphiregulin (AREG), epiregulin (EREG), and neuregulin-1/heregulin (NRG1) predicted for acute cetuximab's functioning. Chronic cetuximab, however, appeared to negatively select initially dominant AREG/EREG/NRG1-positive clones to promote selection of cetuximab-refractory clones exhibiting a knocked-down neuregulin signaling. Our current evolutionary mapping of the transcriptomic changes that occur during cetuximab-induced chronic blockade of EGFR/KRAS WT signaling strongly suggests that mRNAs coding for IFN/STAT1- and EGFR ligands-related genes can be evaluated as novel predictors of efficacy in KRAS WT squamous cancer patients being treated with cetuximab.

Stem cell property epithelial-to-mesenchymal transition is a core transcriptional network for predicting cetuximab (Erbitux™) efficacy in KRAS wild-type tumor cells.

Beyond a well-recognized effect of KRAS mutations in determining de novo inefficacy of cetuximab (CTX) in metastatic colorectal cancer, we urgently need a biomarker signature for predicting CTX efficacy in KRAS wild-type (WT) tumors. CTX-adapted EGFR gene-amplified KRAS WT tumor cell populations were induced by stepwise-chronic exposure of A431 epidermoid cancer cells to CTX. Genome-wide analyses of 44K Agilent's whole human arrays were bioinformatically evaluated by Gene Set Enrichment Analysis (GSEA)-based screening of the KEGG pathway database. Molecular functioning of CTX was found to depend on: (i) The occurrence of a positive feedback loop on Epidermal Growth Factor Receptor (EGFR) activation driven by genes coding for EGFR ligands (e.g., amphiregulin); (ii) the lack of a negative feedback on mitogen-activated protein kinase (MAPK) activation regulated by dual-specificity phosphatases (e.g., DUSP6) and; (iii) the transcriptional status of gene pathways controlling the epithelial-to-mesenchymal transition (EMT) and its reversal (MET) program (actin cytoskeleton and cell-cell communication-e.g., keratins-focal adhesion signaling-e.g., integrins-and EMT-inducing cytokines - e.g., transforming growth factor-ß). Quantitative real-time PCR, high-content immunostaining, and flow-cytometry analyses confirmed that CTX efficacy depends on its ability to promote: (i) Stronger cell-cell contacts by up-regulating the expression of the epithelial markers E-cadherin and occludin; (ii) down-regulation of the epithelial transcriptional repressors Zeb, Snail, and Slug accompanied by restoration of cortical F-actin; and (iii) complete prevention of the CD44(pos)/CD24(neg/low) mesenchymal immunophenotype. The impact of EGFR ligands/MAPK phosphatases gene transcripts in predicting CTX efficacy in KRAS WT tumors may be tightly linked with the ability of CTX to concurrently reverse the EMT status, a pivotal property of migrating cancer stem cells.

Xeroderma pigmentosum: neck lymph node metastasis of a squamous cell carcinoma of the skin treated with cetuximab.

Xeroderma pigmentosum is a genodermatosis characterized by defects in the DNA nucleotide excision repair pathway, which increases the risk of suffering skin cancers. There is lack of information about the efficacy and toxicity of chemotherapy and radiotherapy in the treatment of these patients. We present the case of a xeroderma pigmentosum patient with a neck node recurrence of a squamous cell skin carcinoma that achieved a good response and survival with cetuximab.

Intersticial pneumonitis after oxaliplatin treatment in colorectal cancer

Progressive respiratory failure developed in a 68 year-old female who was treated with single-agent oxaliplatin for colorectal cancer. Only one cycle of 5-fluorouracil had been previously administered. Computed tomography of the chest showed lesions that suggested pulmonary fibrosis. There was an unfavourable response to treatment with corticosteroids, antimicrobial and antifungical agents. Lung biopsy findings were compatible with interstitial pneumonitis. The patient died 20 days after admission due to irreversible respiratory failure. This is the first case reported in the literature of interstitial pneumonitis related to single-agent oxaliplatin administration