Tyrosine kinase inhibitors (TKIs) elicit high response rates among individuals with kinase-driven malignancies, including chronic myeloid leukemia (CML) and epidermal growth factor receptor-mutated non-small-cell lung cancer (EGFR NSCLC). However, the extent and duration of these responses are heterogeneous, suggesting the existence of genetic modifiers affecting an individual's response to TKIs. Using paired-end DNA sequencing, we discovered a common intronic deletion polymorphism in the gene encoding BCL2-like 11 (BIM). BIM is a pro-apoptotic member of the B-cell CLL/lymphoma 2 (BCL2) family of proteins, and its upregulation is required for TKIs to induce apoptosis in kinase-driven cancers. The polymorphism switched BIM splicing from exon 4 to exon 3, which resulted in expression of BIM isoforms lacking the pro-apoptotic BCL2-homology domain 3 (BH3). The polymorphism was sufficient to confer intrinsic TKI resistance in CML and EGFR NSCLC cell lines, but this resistance could be overcome with BH3-mimetic drugs. Notably, individuals with CML and EGFR NSCLC harboring the polymorphism experienced significantly inferior responses to TKIs than did individuals without the polymorphism (P = 0.02 for CML and P = 0.027 for EGFR NSCLC). Our results offer an explanation for the heterogeneity of TKI responses across individuals and suggest the possibility of personalizing therapy with BH3 mimetics to overcome BIM-polymorphism-associated TKI resistance.

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BACKGROUND:The current study was performed to report the long-term results of a trial comparing concurrent chemotherapy and radiotherapy (CCRT) with surgery and adjuvant radiotherapy (RT) in patients with stage III/IV nonmetastatic head and neck squamous cell carcinoma. METHODS: Patients with stage III/IV resectable head and neck squamous cell carcinoma were randomized to surgery followed by RT or CCRT. The trial was halted prematurely due to poor accrual. Human papillomavirus status was tested on archival material using polymerase chain reaction sequencing. RESULTS: Of the total of 119 patients, 60 patients were randomized to primary surgery (S arm) and 59 patients were randomized to CCRT (C arm). Human papillomavirus status was tested in 75 patients, and only 3 were found to be positive. The median follow-up for surviving patients was 13 years. Analysis of the entire cohort demonstrated no statistically significant difference in overall survival and disease-specific survival (DSS): 5-year rates were 45% versus 35% for overall survival (P 5.262) and 56% versus 46% for DSS (P 5.637) for the S arm and C arm, respectively. Analysis by subsites indicated that this difference favoring the S arm was mainly driven by survival data among patients with cancers of the oral cavity and maxillary sinus. For patients with oral cavity cancer, survival was significantly better in those who underwent primary surgery compared with CCRT; the 5-year DSS rate was 68% versus 12% for the S arm and C arm, respectively (P 5.038). For patients with cancers of the maxillary sinus, the 5-year DSS rate was 71% for patients on the S arm and 0% for patients on the C arm (P 5.05). CONCLU-SIONS: These long-term results demonstrate a significant advantage for primary surgery in patients with cancers of the oral cavity or maxillary sinus, providing strong support for primary surgery as the main modality of treatment for these subsites. In other subsites, CCRT and surgery with adjuvant RT were found to demonstrate similar efficacy for survival in patients with advanced resectable tumors. Cancer 2015;121:1599-607.

Purpose Mesenchymal epithelial transition factor ( MET) activation has been implicated as an oncogenic driver in epidermal growth factor receptor ( EGFR)–mutant non–small-cell lung cancer (NSCLC) and can mediate primary and secondary resistance to EGFR tyrosine kinase inhibitors (TKI). High copy number thresholds have been suggested to enrich for response to MET inhibitors. We examined the clinical relevance of MET copy number gain (CNG) in the setting of treatment-naive metastatic EGFR-mutant–positive NSCLC. Patients and Methods MET fluorescence in situ hybridization was performed in 200 consecutive patients identified as metastatic treatment-naïve EGFR-mutant–positive. We defined MET-high as CNG greater than or equal to 5, with an additional criterion of MET/centromeric portion of chromosome 7 ratiο greater than or equal to 2 for amplification. Time-to-treatment failure (TTF) to EGFR TKI in patients identified as MET-high and -low was estimated by Kaplan-Meier method and compared using log-rank test. Multiregion single-nucleotide polymorphism array analysis was performed on 13 early-stage resected EGFR-mutant–positive NSCLC across 59 sectors to investigate intratumoral heterogeneity of MET CNG. Results Fifty-two (26%) of 200 patients in the metastatic cohort were MET-high at diagnosis; 46 (23%) had polysomy and six (3%) had amplification. Median TTF was 12.2 months (95% CI, 5.7 to 22.6 months) versus 13.1 months (95% CI, 10.6 to 15.0 months) for MET-high and -low, respectively ( P = .566), with no significant difference in response rate regardless of copy number thresholds. Loss of MET was observed in three of six patients identified as MET-high who underwent postprogression biopsies, which is consistent with marked intratumoral heterogeneity in MET CNG observed in early-stage tumors. Suboptimal response (TTF, 1.0 to 6.4 months) to EGFR TKI was observed in patients with coexisting MET amplification (five [3.2%] of 154). Conclusion Although up to 26% of TKI-naïve EGFR-mutant–positive NSCLC harbor high MET CNG by fluorescence in situ hybridization, this did not significantly affect response to TKI, except in patients identified as MET-amplified. Our data underscore the limitations of adopting arbitrary copy number thresholds and the need for cross-assay validation to define therapeutically tractable MET pathway dysregulation in EGFR-mutant–positive NSCLC.

BACKGROUND: Serum carcinoembryonic antigen (CEA) is the only marker recommended for surveillance of colorectal cancer (CRC) recurrence; its sensitivity and specificity, however, are suboptimal. This study sought to evaluate the values of postoperative serum methylation levels of 7 genes for prognostication and especially for recurrence detection after curative resection. METHODS: This prospective cohort study included 150 patients with stage I-III CRC from whom 3 consecutive blood sampling was taken 1 week before, and 6 months and 1 year after operation. Methylation levels of 7 genes were evaluated via quantitative methylation-specific polymerase chain reaction. Serum CEA was measured in parallel. Univariate and multivariate survival analyses were followed by construction of receiver operating characteristic curves for recurrence detection. RESULTS: After a median follow-up of 59 months, 43 patients (28.7%) developed recurrent lesions. High serum methylation levels of TAC1 in serum at 6-month follow-up (6M-FU), and SEPT9 at 1-year follow-up (1Y-FU) were independent predictors for tumor recurrence and unfavorable cancer-specific survival (CSS) (P <.05 in all tests). Serum NELL1 methylation levels were significant alone for CSS at both 6M-FU and 1Y-FU, but not for disease-free survival. Dynamic changes of TAC1 and SEPT9 with methylation increment were also independently predictive for recurrence (P <.05 in all tests). More importantly, TAC1 at 6M-FU and SEPT9 at 1Y-FU exhibited earlier detection of potential recurrences compared with concurrent serum CEA. CONCLUSIONS: Levels of TAC1 and SEPT9 methylation detected in postoperative sera of patients with CRC appear to be novel promising prognostic markers and may probably be considered for monitoring of CRC recurrence. Cancer 2014;120:3131-41.