Search

Background: Despite therapeutic advances, lung cancer prognosis remains poor. Loss of heterozygosity (LOH) in the 3p21 region is well documented in lung cancer, but the specific causative genes have not been identified. Materials and Methods: Here, we aimed to examine the clinical impact of miR‐135a, located in the 3p21 region, in lung cancer. miR‐135a expression was assessed using quantitative real‐time polymerase chain reaction. LOH was analyzed at microsatellite loci D3S1076 and D3S1478, and promoter methylation status was determined by pyrosequencing of resected samples of primary non‐small‐cell lung cancer (NSCLC). The regulation of telomerase reverse transcriptase (TERT) was evaluated in lung cancer cells H1299 by luciferase report assays after treatment with miR‐135a mimics. Results: miR‐135a was significantly downregulated in squamous cell cancer (SCC) tumor tissues compared to normal tissues (p = 0.001). Low miR‐135a expression was more frequent in patients with SCC (p = 2.9 × 10−4) and smokers (p = 0.01). LOH and hypermethylation were detected in 27.8% (37/133) and 17.3% (23/133) of the tumors, respectively. Overall, 36.8% (49/133) of the NSCLC cases harbored either miR‐135a LOH or promoter hypermethylation. The frequencies of LOH and hypermethylation were significantly associated with SCCs (p = 2 × 10−4) and late‐stage (p = 0.04), respectively. MiR‐135a inhibited the relative luciferase activity of psiCHECK2‐TERT‐3'UTR. Conclusion: These results suggest that miR‐135a may act as a tumor suppressor to play an important role in lung cancer carcinogenesis, which will provide a new insight into the translational value of miR‐135a. Further large‐scale studies are required to confirm these findings. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the relationship between genetic variants in LKB1/AMPK/mTOR pathway and treatment outcomes of patients with non‐small cell lung cancer (NSCLC) treated with chemotherapy. A total of 379 patients with NSCLC who underwent first‐line paclitaxel‐cisplatin chemotherapy was enrolled. The associations between 19 single nucleotide variants (SNVs) in the LKB1/AMPK/mTOR pathway and the chemotherapy response and overall survival (OS) were analyzed. Among the SNVs analyzed, AKT1 rs2494750G>C and TSC1 rs2809244C>A were associated with clinical outcomes after chemotherapy in multivariate analyses. The AKT1 rs2494750G>C was significantly associated with a better response to chemotherapy (adjusted odds ratio [aOR]: 1.92, 95% confidence interval [CI]: 1.02–3.62, p = 0.04). The TSC1 rs2809244C>A were significantly associated with better OS (adjusted hazard ratio [aHR]: 0.79, 95% CI: 0.62–0.99, p = 0.04). When stratified by tumor histology, AKT1 rs2494750G>C exhibited a significant association with the chemotherapy response only in adenocarcinoma and TSC1 rs2809244C>A was also significantly associated with OS only in adenocarcinoma. This result suggests that the AKT1 rs2494750G>C and TSC1 rs2809244 C>A may be useful for predicting the clinical outcome of first‐line paclitaxel‐cisplatin chemotherapy in NSCLC. [ABSTRACT FROM AUTHOR]

Background: We investigated the clinical features and surgical outcomes of lung adenocarcinoma with minimal solid or micropapillary (S/MP) components, with a focus on stage IA. Methods: We enrolled 506 patients with lung adenocarcinoma who underwent curative resection in this study. Clinical features and surgical outcomes were compared between the groups with and without the S/MP subtype (S/MP+ and S/MP−, respectively), and between the group with an S/MP proportion of ≤5% (S/MP5) and the S/MP−. Results: The S/MP subtype was present in 247 patients (48.8%); 129 (25.5%) were grouped as the S/MP5 group. The S/MP+ and S/MP5 groups had larger tumors, higher frequency of lymph node metastasis, and more advanced stages of disease than the S/MP− group (P < 0.001, all comparisons). Pleural, lymphatic, and vascular invasions occurred more frequently in the S/MP+ and S/MP5 groups (P < 0.001, all comparisons for S/MP+ vs. S/MP−; P ≤ 0.01, all comparisons for S/MP5 vs. S/MP−). The S/MP+ and S/MP5 groups showed a shorter time to recurrence and cancer‐related death than the S/MP− group(P < 0.001, both comparisons). For stage I, the presence or absence of the S/MP subtype defined prognostic subgroups better than the stage IA/IB classification. Notably, in the multivariate analysis, the minimal S/MP component was a significant predictor of recurrence, even in stage IA. Conclusions: The presence of the minimal S/MP component was a significant predictor of poor prognosis after surgery, even in stage IA patients. Clinical trials to evaluate the advantages of adjuvant chemotherapy for this subset of patients and further investigations to understand underlying biological mechanisms of poor prognosis are needed. Key points: Significant findings of the study: We demonstrated that only minimal presence of solid or micropapillary component was profoundly associated with aggressive clinicopathological features and poor prognosis after complete resection even in stage IA lung adenocarcinoma. What this study adds: Our results suggest that minimal presence of these subtypes is a strong prognostic factor which should be taken into account in the risk assessment for adjuvant chemotherapy in lung adenocarcinoma. [ABSTRACT FROM AUTHOR]

Background: Achaete‐scute homolog 1 (ASCL1) is a basic helix‐loop‐helix transcription factor and is essential in the differentiation of neuroendocrine cells and neural tissues. ASCL1 is frequently overexpressed in small cell lung cancer (SCLC) and plays a crucial role in the pathogenesis of SCLC. Methods: This study was conducted to identify the association between single nucleotide polymorphisms (SNPs) in ASCL1 target genes and clinical outcomes of patients with SCLC after chemotherapy. A total of 261 patients diagnosed with SCLC were enrolled in this study. The association between 103 SNPs in 58 ASCL1 target genes and the response to chemotherapy and survival of patients with SCLC were analyzed. Results: Among the 103 SNPs, 10 SNPs were significantly associated with the response to chemotherapy, and 19 SNPs were associated with OS in multivariate analyses. Among these, Dopa Decarboxylase (DDC) rs12666409A>T was significantly associated with both a worse response to chemotherapy and worse OS (adjusted odds ratio [aOR] = 0.40, 95% CI = 0.18–0.90, P = 0.03; adjusted hazard ratio [aHR] = 1.52, 95% CI = 1.10–2.10, P = 0.01, respectively, under a dominant model). In a stage‐stratified analysis, the association was significant only in the extensive disease subgroup (aOR = 0.19, 95% CI = 0.06–0.60, P = 0.01; aHR = 1.73, 95% CI = 1.16–2.56, P = 0.01, respectively, under a dominant model), but not in the limited disease subgroup. Conclusion: The results of our study suggest that DDC rs12666409A>T may be useful markers for predicting the clinical outcomes of patients with SCLC undergoing chemotherapy. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the associations between polymorphisms of genes involved in the LKB1 pathway and the prognosis of patients with non‐small cell lung cancer (NSCLC) after surgical resection. Twenty‐three single nucleotide polymorphisms (SNPs) in the LKB1 pathway were investigated in 782 patients with NSCLC who underwent curative surgery. The association of SNPs with overall survival (OS) and disease‐free survival (DFS) were analyzed. Among the 23 SNPs investigated, TSC2 rs30259G > A was associated with significantly worse OS and DFS (adjusted hazard ratio for OS 1.88, 95% confidence interval 1.21–2.91, P = 0.005; adjusted hazard ratio for DFS 1.65, 95% confidence interval 1.15–2.38, P = 0.01, under codominant models, respectively). Subgroup analysis showed that SNPs were significantly associated with survival outcomes in squamous cell carcinoma, ever‐smokers, and stage I, but not in adenocarcinoma, never‐smokers, and stage II–IIIA. The results suggest that TSC2 rs30259G > A may be useful to predict prognosis in patients with NSCLC, especially squamous cell carcinoma, after curative surgery. [ABSTRACT FROM AUTHOR]

A high-throughput mapping method of RNA- RNA interactions by crosslinking, ligation, and sequencing of hybrids ( CLASH) can not only provide information about canonical but also non-canonical interactions. We evaluated the associations between variants in micro RNA target sites using CLASH data and survival outcomes of 782 early-stage non-small cell lung cancer ( NSCLC) patients who underwent curative surgical resection. Among the 100 variants studied, two variants showed significant association with survival outcomes. The POLR2A rs2071504 C > T variant was associated with poor overall and disease-free survival under a dominant model (hazard ratio [ HR] 1.42, 95% confidence interval [ CI] 1.08-1.88; P = 0.01 and HR 1.34, 95% CI 1.08-1.67; P = 0.01, respectively). Patients carrying the NR2F6 rs2288539 TT genotype showed significantly better overall survival than those with the NR2F6 rs2288539 CC or CT genotypes ( HR 0.13, 95% CI 0.02-0.90; P = 0.04). These findings suggest that POLR2A rs2071504 C > T and NR2F6 rs2288539 C > T can influence prognosis in early-stage NSCLC patients. [ABSTRACT FROM AUTHOR]