Clinical characteristics and course of pulmonary artery stump thrombosis following lung cancer surgery: A retrospective study from tertiary care hospital.

The data regarding pulmonary artery stump thrombosis (PAST) after lung cancer surgery are insufficient. The aim of the present study was to evaluate the incidence, clinical characteristics, and prognosis of PAST. We retrospectively investigated the incidence and clinical characteristics of PAST among patients who underwent lung resection for lung cancer at 2 institutions. We compared the clinical parameters between PAST and pulmonary embolism (PE) and examined the clinical course of patients with PAST. Of the 1885 patients, PAST was found in 36 patients (1.9%). Right lower lobectomy (n = 13) and middle-lower bilobectomy (n = 9) were the most common types of surgery. The median time interval from lung resection to the detection of PAST was 3.8 months. Immobilization and a history of cerebrovascular disease were not observed in the PAST group. Most of the patients with PAST (91.7%) were diagnosed incidentally, whereas many patients with PE (75.9%) were symptomatic at the time of diagnosis. During the follow-up, one patient (2.8%) had contralateral PE complications. However, no patients in the PAST group experienced pulmonary thromboembolism-related in-hospital death or adverse outcomes. There was no difference in the prognosis of patients with PAST according to the administration of anticoagulation. PAST was rarely detected in lung cancer patients on follow-up chest computed tomography after lung resection. Patients with PAST were asymptomatic in most cases and had relatively favorable clinical outcomes. However, these patients are at risk of contralateral PE, despite its rarity.

Lipid Metabolism Pathway Genes and Lung Cancer: ACADSB rs12220683G>C Is Associated with Better Survival Outcome in Patients with Non-Small Cell Lung Cancer.

INTRODUCTION: Altered lipid metabolism has been reported to be associated with prognosis in multiple cancers. This study aimed to investigate the association of polymorphisms in lipid metabolism pathway genes with survival outcomes in patients with surgically resected non-small cell lung cancer (NSCLC). METHODS: In total, 744 patients with surgically resected NSCLC (380 in the discovery cohort and 364 in the validation cohort) were included in this study. The association between 176 polymorphisms of lipid metabolism pathway genes and the clinical outcomes of NSCLC patients was analyzed. RESULTS: Among the polymorphisms investigated, ACADSB rs10902859G>A was associated with significantly better overall survival (OS) in the discovery, validation, and combined cohorts. ACADSB rs10902859G>A was located in the repressed region and had strong linkage disequilibrium (D' = 1.00 and r2 = 0.94), with rs12220683G>C located in the H3K4me3 peak region, which indicates the presence of active promoters. ACADSB rs12220683G>C was also associated with better OS in the discovery, validation, and combined cohorts (in a dominant model; adjusted hazard ratio [aHR] = 0.53, 95% confidence interval [CI] = 0.30-0.94, p = 0.03; aHR = 0.37, 95% CI = 0.15-0.89, p = 0.03; and aHR = 0.47, 95% CI = 0.29-0.75, p = 0.002, respectively). In vitro luciferase assay demonstrated that the promoter activity of ACADSB was significantly increased in the rs12220683 variant C allele compared with that in the wild G allele (p = 3 × 10-5). CONCLUSION: These results suggest that ACADSB rs12220683G>C increases promoter activity and that increased ACADSB expression may result in better OS in patients with surgically resected NSCLC.

Genetic variants in key necroptosis regulators predict prognosis of non-small cell lung cancer after surgical resection.

BACKGROUND: Necroptosis is a regulated inflammatory cell death which plays a significant role in cancer development and progression. In this study, we evaluated whether genetic variants in key regulators of necroptosis may affect survival outcome of non-small cell lung cancer (NSCLC) patients after surgical resection. METHODS: A total of 674 patients who underwent curative surgery were included. Fifteen genetic variants in key regulators of necroptosis (RIPK1, RIPK3, and MLKL) were selected. The association of these variants with survival outcomes was evaluated. RESULTS: Two variants, RIPK1 rs17548629C > T and MLKL rs877375G > C, were associated with better overall survival and disease-free survival in multivariate analyses. When the patients were divided according to histology, the associations were significant only in adenocarcinoma, but not in squamous cell carcinoma. RIPK1 rs17548629 C-to-T change was associated with significantly increased luciferase activity by modulating the binding of miR-642a. Promoter assays showed a significantly increased promoter activity in MLKL rs877375C allele compared to G allele. Consistently, the mRNA expression level of RIPK1 and MLKL showed significant positive correlation with RIPK1 rs17548629C-to-T and MLKL rs877375G-to-C changes. CONCLUSION: Two genetic variants in key regulators in necroptosis, RIPK1 rs17548629C > T and MLKL rs877375G > C, may be used as biomarkers to predict survival outcomes in surgically resected NSCLC patients.

Regulating POLR3G by MicroRNA-26a-5p as a promising therapeutic target of lung cancer stemness and chemosensitivity.

Cancer stem cells (CSCs) identified in lung cancer exhibit resistance to chemotherapy, radiotherapy, and targeted therapy. Therefore, a technology for controlling CSCs is needed to overcome such resistance to cancer therapy. Various evidences about the association between epithelial-mesenchymal transition related transcriptomic alteration and acquisition of CSC phenotype have been proposed recently. Down-regulated miR-26a-5p is closely related to mesenchymal-like lung cancer cell lines. These findings suggest that miR-26a-5p might be involved in lung cancer stemness. RNA polymerase III subunit G (POLR3G) was selected as a candidate target of miR-26a-5p related to cancer stemness. It was found that miR-26a-5p directly regulates the expression of POLR3G.Overexpression of miR-26a-5p induced a marked reduction of colony formation and sphere formation. Co-treatment of miR-26a-5p and paclitaxel decreased cell growth, suggesting that miR-26a-5p might play a role as a chemotherapy sensitizer. In the cancer genome atlas data, high miR-26a-5p and low POLR3G expression were also related to higher survival rate of patients with lung adenocarcinoma. These results suggest that miR-26a-5p can suppress lung cancer stemness and make cancer cell become sensitive to chemotherapy. This finding provides a novel insight into a potential lung cancer treatment by regulating stemness.

Genetic variants in LKB1/AMPK/mTOR pathway are associated with clinical outcomes of chemotherapy in non-small cell lung cancer.

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.

Pulmonary vein stump thrombosis after lung resection for lung cancer: clinical features and outcome.

Pulmonary vein stump thrombosis (PVST) is uncommonly encountered postoperative in-situ thrombosis in the stump of pulmonary veins after lung resection. Data regarding the incidence and clinical behaviour of PVST are scarce. Thus, this study aims to investigate the incidence, clinical characteristics and outcome of PVST after lung resection in patients with lung cancer. Follow-up enhanced chest computed tomography (CT) scans acquired after the surgery were retrospectively reviewed to determine PVST presence for patients with lung cancer who underwent lung resection in two tertiary referral centres. Out of the 1885 patients with lung cancer who underwent lobectomy or more extensive lung resection, PVST was observed in 37 patients (2.0%) on their follow-up chest CT. Most stump thrombi were observed in the left superior pulmonary vein [35 (94.6%)] and in patients who underwent left upper lobectomy [34 (91.9%)]. At the last CT follow-up of each patient, 33 (89.2%) exhibited complete resolution, three partial resolution and one stabilization. Eleven (29.7%) patients received anticoagulant therapy after the diagnosis. The rate of complete PVST resolution did not differ significantly between the anticoagulation and nonanticoagulation groups. None of the PVST patients experienced systemic embolic events, regardless of anticoagulation. The PVST incidence diagnosed at routine chest CT follow-up following lung cancer surgery was 2%. PVST was characterized by a benign clinical course without progression and systemic embolization, regardless of anticoagulation. However, further studies are required to determine individualized therapeutic strategies, including anticoagulation.

Epigenetic readers and lung cancer: the rs2427964C>T variant of the bromodomain and extraterminal domain gene BRD3 is associated with poorer survival outcome in NSCLC.

Bromodomain and extraterminal domain (BET) proteins are epigenetic readers that regulate gene expression. We investigated whether variants in BET genes are associated with survival outcomes for lung cancer. To do this, the associations between 77 variants in BET family genes and survival outcomes were analyzed in 773 non-small-cell lung cancer (NSCLC) patients who underwent surgery (349 and 424 patients in the discovery and validation cohorts, respectively). We found that six variants were significantly associated with overall survival (OS) in the discovery cohort, and one variant (rs2506711C>T) was replicated in the validation cohort. BRD3 rs2506711C>T is located in the repressed area and has a strong linkage disequilibrium with rs2427964C>T in the promoter region. BRD3 rs2427964C>T was significantly associated with worse OS in the discovery cohort, validation cohort, and combined analysis. In a luciferase assay, promoter activity in the BRD3 rs2427964 T allele was significantly higher than that in the BRD3 rs2427964 C allele, which selectively bound with the transcriptional repressor SIN3A. Knockdown of BRD3 with BRD3-specific siRNA decreased the proliferation and migration of lung cancer cells while also increasing the rate of apoptosis. These results suggest that BRD3 rs2427964C>T increases BRD3 expression through increased promoter activity, which is associated with poor prognosis for lung cancer.

Genetic variants in histone modification regions are associated with the prognosis of lung adenocarcinoma.

We investigated the association between genetic variants in the histone modification regions and the prognosis of lung adenocarcinoma after curative surgery. Potentially functional SNPs were selected using integrated analysis of ChIP-seq and RNA-seq. The SNPs were analyzed in a discovery set (n = 166) and a validation set (n = 238). The associations of the SNPs with overall survival (OS) and disease-free survival (DFS) were analyzed. A total of 279 SNPs were selected for genotyping. Among these, CAPN1 rs17583C>T was significantly associated with better OS and DFS (P = 0.001 and P = 0.007, respectively), and LINC00959 rs4751162A>G was significantly associated with worse DFS (P = 0.008). Luciferase assays showed a significantly lower promoter activity of CAPN1 in the rs17583 T allele than C allele (P = 0.008), and consistently the CT + TT genotypes had significantly lower CAPN1 expression than CC genotype (P = 0.01) in clinical samples. The rs4751162 G allele had higher promoter activity of GLRX3 than A allele (P = 0.05). The motif analyses and ChIP-qPCR confirmed that the variants are located in the active promoter/enhancer regions where transcription factor binding occurs. This study showed that genetic variants in the histone modification regions could predict the prognosis of lung adenocarcinoma after surgery.

Genetic Polymorphisms in Activating Transcription Factor 3 Binding Site and the Prognosis of Early-Stage Non-Small Cell Lung Cancer.

BACKGROUND: Activating transcription factor 3 (ATF3) plays a significant role in cancer development and progression. We investigated the association between variants in expression quantitative trait loci (eQTLs) within ATF3 binding regions and the prognosis of non-small cell lung cancer (NSCLC) after surgery. METHODS: A total of 772 patients with NSCLC who underwent curative surgery were enrolled. Using a public database (http://galaxyproject.org), we selected 104 single nucleotide polymorphisms (SNPs) in eQTLs in the ATF3 binding regions. The association of those SNPs with disease-free survival (DFS) was evaluated. RESULTS: Among those SNPs, HAX1 rs11265425T>G was associated with significantly worse DFS (aHR = 1.30, 95% CI = 1.00-1.69, p = 0.05), and ME3 rs10400291C>A was associated with significantly better DFS (aHR = 0.66, 95% CI = 0.46-0.95, p = 0.03). Regarding HAX1 rs11265425T>G, the significant association remained only in adenocarcinoma, and the association was significant only in squamous cell carcinoma regarding ME3 rs10400291C>A. ChIP-qPCR assays showed that the two variants reside in active enhancers where H3K27Ac and ATF3 binding occurs. Promoter assays showed that rs11265425 G allele had significantly higher HAX1 promoter activity than T allele. HAX1 RNA expression was significantly higher in tumor than in normal lung, and higher in rs11265425 TG+GG genotypes than in TT genotype. Conversely, ME3 expression was significantly lower in tumor than in normal lung, and higher in rs10400291 AA genotype than in CC+CA genotypes. CONCLUSIONS: In conclusion, this study shows that the functional polymorphisms in ATF3 binding sites, HAX1 rs11265425T>G and ME3 rs10400291C>A are associated with the clinical outcomes of patients in surgically resected NSCLC.

Clinical implication of minimal presence of solid or micropapillary subtype in early-stage lung adenocarcinoma.

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.

Genetic Variants in One-Carbon Metabolism Pathway Predict Survival Outcomes of Early-Stage Non-Small Cell Lung Cancer.

BACKGROUND: This study was conducted to investigate the association between genetic variants in one-carbon metabolism and survival outcomes of surgically resected non-small cell lung cancer (NSCLC). METHODS: We genotyped 41 potentially functional variants of 19 key genes in the one-carbon metabolism pathway among 750 NSCLC patients who underwent curative surgery. The association between genetic variants and overall survival (OS)/disease-free survival (DFS) were analyzed. RESULTS: Among the 41 single-nucleotide polymorphisms (SNPs) analyzed, 4 SNPs (MTHFD1L rs6919680T>G and rs3849794T>C, MTR rs2853523C>A, and MTHFR rs4846049G>T) were significantly associated with survival outcomes. MTHFD1L rs6919680T>G and MTR rs2853523C>A were significantly associated with better OS (adjusted hazard ratio [aHR] = 0.73, 95% confidence interval [CI] = 0.54-0.99, p = 0.04) and worse OS (aHR = 2.14, 95% CI = 1.13-4.07, p = 0.02), respectively. MTHFD1L rs3849794T>C and MTHFR rs4846049G>T were significantly associated with worse DFS (aHR = 1.41, 95% CI = 1.08-1.83, p = 0.01; and aHR = 1.97, 95% CI = 1.10-3.53, p = 0.02, respectively). When the patients were divided according to histology, the associations were significant only in squamous cell carcinoma (SCC), but not in adenocarcinoma (AC). In SCC, MTHFD1L rs6919680T>G and MTR rs2853523C>A were significantly associated with better OS (aHR = 0.64, 95% CI = 0.41-1.00, p = 0.05) and worse OS (aHR = 2.77, 95% CI = 1.11-6.91, p = 0.03), respectively, and MTHFD1L rs3849794T>C and MTHFR rs4846049G>T were significantly associated with worse DFS (aHR = 1.73, 95% CI = 1.17-2.56, p = 0.01; and aHR = 2.78, 95% CI = 1.12-6.88, p = 0.03, respectively). CONCLUSIONS: Our results suggest that the genetic variants in the one-carbon metabolism pathway could be used as biomarkers for predicting the clinical outcomes of patients with early-stage NSCLC.

Expression of key regulatory genes in necroptosis and its effect on the prognosis in non-small cell lung cancer.

Background: Accumulating evidence suggests that necroptosis, or programmed necrotic cell death, may play a significant role in cancer. We evaluated the expression of key molecules in necroptosis and their association with clinical features and prognosis in NSCLC. Methods: A total of 253 NSCLC patients (96 squamous cell carcinoma [SCC] cases and 157 adenocarcinoma [AC] cases) who underwent curative resection were included. Tumor tissues and corresponding normal tissues were investigated for relative mRNA expression levels of RIPK1, RIPK3, and MLKL. Difference in disease free survival (DFS) was analyzed according to the expression levels of these molecules in tumor tissues. Results: NSCLC tissues had significantly lower expression of RIPK1, RIPK3, and MLKL than normal tissues (P = 1 x 10-4, P = 8 x 10-6, and P = 4 x 10-8, respectively). In subgroup analysis, SCCs had significantly lower RIPK1, RIPK3, and MLKL expression (P = 5 x 10-4, P = 3 x 10-15, P = 1 x 10-5, respectively), and ACs had significantly lower RIPK1 and MLKL expression (P = 0.01 and P = 6 x 10-4, respectively) than normal tissues. Low expression of RIPK1, RIPK3, and MLKL in tumors was associated with a worse DFS (HR = 1.71, P = 0.01; HR = 1.53, P = 0.04; and HR = 1.53, P = 0.04, respectively) in a multivariate analysis. In SCC, none of the RIPK1, RIPK3, and MLKL expression was significantly associated with DFS. However, in AC, low expression of RIPK1, RIPK3, and MLKL was significantly associated with worse DFS (HR = 1.67, P = 0.03; HR = 1.70, P = 0.03; and HR = 1.81, P = 0.02, respectively). Conclusions: Key regulatory genes in necroptosis, RIPK1, RIPK3, and MLKL, were downregulated in NSCLC, and their lower expression in NSCLC may be used to predict early recurrence after curative resection, especially in AC.

The effect of susceptibility variants, identified in never-smoking female lung cancer cases, on male smokers.

BACKGROUND/AIMS: Genome wide and candidate gene association studies have identified polymorphisms associated with the risk of lung cancer in never-smokers. This study was conducted to evaluate the association between 11 polymorphisms identified in female never smokers and the lung cancer risk in male smokers. METHODS: This study included 714 lung cancer patients and 626 healthy controls. The polymorphisms were genotyped using SEQUENOM MassARRAY iPLEX assay or Taq-Man assay. RESULTS: Two polymorphisms were associated with the risk of lung cancer in male smokers, as in female never smokers. Male smokers carrying the rs4975616 variant allele had a significantly decreased risk of lung cancer (in a codominant model: odds ratio, 0.77; 95% confidence interval, 0.61 to 0.96; p = 0.02). The rs9387478 polymorphism also reduced lung cancer risk in male smokers (in a codominant model: odds ratio, 0.85; 95% confidence interval, 0.73 to 0.997; p = 0.046). In a stratified analysis, the association between these polymorphisms and the risk of lung cancer was predominant in lighter smokers and for cases of adenocarcinoma. CONCLUSION: These results suggest that a subset of polymorphisms known to be associated with the risk of lung cancer in female never smokers is also associated with the risk of lung cancer in male smokers.

Genetic Variant of Notch Regulator DTX1 Predicts Survival After Lung Cancer Surgery.

BACKGROUND: We evaluated the association between genetic variants in the Notch pathway and survival outcomes of patients with surgically resected NSCLC. METHODS: Sixty-four single nucleotide polymorphisms (SNPs) in the Notch pathway genes were evaluated in the discovery study (n = 354) and two sequential validation studies (n = 772 and n = 746, respectively). The association of genotype with overall survival (OS) and disease-free survival (DFS) was evaluated. RESULTS: Of the 64 SNPs analyzed in the discovery study, 9 were significantly associated with OS or DFS. Among them, the association remained significant only for Deltex-1 (DTX1) rs1732786A>G in the first validation study. The second validation study confirmed again the association between DTX1 rs1732786A>G and survival outcomes. In the combined analysis, rs1732786A>G was significantly associated with better OS and DFS (adjusted HR ·aHR· for OS, 0.75; 95% CI 0.64-0.87; P = 0.0002; aHR for DFS, 0.79; 95% CI 0.71-0.89; P = 0.0001). In vitro luciferase assay showed that the rs1732786G allele was associated with higher promoter activity compared to rs1732786A allele. Consistently, relative mRNA expression level of DTX1 showed significant positive correlation with rs1732786 A-to-G change (Ptrend = 0.02) in tumor tissues. CONCLUSIONS: These results suggest that DTX1 rs1732786 is a potential prognostic factor that may have clinical utility in the management of early stage NSCLC.

Glucose transporter 3 gene variant is associated with survival outcome of patients with non-small cell lung cancer after surgical resection.

This study was conducted to explore whether polymorphisms of glucose transporter 3 (GLUT3) gene affect the prognosis of patients with non-small cell lung cancer (NSCLC) after surgical resection. Four single nucleotide polymorphisms (SNPs) in GLUT3 were investigated in a total of 782 patients with NSCLC who underwent curative surgery. The association of the SNPs with overall survival (OS) and disease free survival (DFS) was analyzed. Among the four SNPs investigated, GLUT3 rs7309332C>T was significantly associated with OS and DFS in multivariate analyses. The SNP was associated with significantly worse OS (adjusted hazard ratio [aHR] = 1.62, 95% confidence interval [CI] = 1.04-2.53, P = 0.03, under recessive model), and worse DFS (aHR = 1.64, 95% CI = 1.18-2.29, P = 0.003, under recessive model). When stratified by tumor histology, the association between the GLUT3 rs7309332C>T and OS/DFS was not limited to either squamous cell carcinoma (SCC) or adenocarcinoma (AC), although the significant association remained only in AC for OS (P = 0.40 for SCC and P = 0.04 for OS) and only in SCC for DFS (P = 0.03 for SCC and P = 0.08 for OS). When AC patients were stratified according to EGFR mutation status, the SNP was significantly associated with DFS in patients with EGFR mutant tumors (aHR = 2.47, 95% CI = 1.15-5.30, P = 0.02, under recessive model), but not in those with EGFR wild-type tumors. This study suggests that genetic variation in GLUT3 may be useful in predicting survival of patients with early stage NSCLC.

TSC2 genetic variant and prognosis in non-small cell lung cancer after curative surgery.

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.

Functional intronic variant of SLC5A10 affects DRG2 expression and survival outcomes of early-stage non-small-cell lung cancer.

RegulomeDB is a new tool that can predict the regulatory function of genetic variants. We applied RegulomeDB in selecting putative functional variants and evaluated the relationship between these variants and survival outcomes of surgically resected non-small-cell lung cancer. Among the 244 variants studied, 14 were associated with overall survival (P < 0.05) in the discovery cohort and one variant (rs2257609 C>T) was replicated in the validation cohort. In the combined analysis, rs2257609 C>T was significantly associated with worse overall and disease-free survival under a dominant model (P = 2 × 10-5 and P = 0.001, respectively). rs2257609 is located in the SLC5A10 intron, but RegulomeDB predicted that this variant affected DRG2, not SLC5A10 expression. The expression level of SLC5A10 was not different with the rs2257609 genotype. However, DRG2 expression was different according to the rs2257609 genotype (Ptrend   = 0.03) and was significantly higher in tumor than in non-malignant lung tissues (P = 1 × 10-5 ). Luciferase assay also showed higher promoter activity of DRG2 in samples with the rs2257609 T allele (P < 0.0001). rs2257609 C>T affected DRG2 expression and, thus, influenced the prognosis of early-stage non-small-cell lung cancer. This study was approved by the Institutional Review Broad of Kyungpook National University of Hospital (Approval No. KNUMC 2014-04-210-003).

Quiescin Sulfhydryl Oxidase 1 (QSOX1) Secreted by Lung Cancer Cells Promotes Cancer Metastasis.

As lung cancer shows the highest mortality in cancer-related death, serum biomarkers are demanded for lung cancer diagnosis and its treatment. To discover lung cancer protein biomarkers, secreted proteins from primary cultured lung cancer and adjacent normal tissues from patients were subjected to LC/MS⁻MS proteomic analysis. Quiescin sulfhydryl oxidase (QSOX1) was selected as a biomarker candidate from the enriched proteins in the secretion of lung cancer cells. QSOX1 levels were higher in 82% (51 of 62 tissues) of lung cancer tissues compared to adjacent normal tissues. Importantly, QSOX1 serum levels were significantly higher in cancer patients (p < 0.05, Area Under curve (AUC) = 0.89) when measured by multiple reaction monitoring (MRM). Higher levels of QSOX1 were also uniquely detected in lung cancer tissues, among several other solid cancers, by immunohistochemistry. QSOX1-knock-downed Lewis lung cancer (LLC) cells were less viable from oxidative stress and reduced migration and invasion. In addition, LLC mouse models with QSOX1 knock-down also proved that QSOX1 functions in promoting cancer metastasis. In conclusion, QSOX1 might be a lung cancer tissue-derived biomarker and be involved in the promotion of lung cancers, and thus can be a therapeutic target for lung cancers.

Glucose Transporter 1 Gene Variants Predict the Prognosis of Patients with Early-Stage Non-small Cell Lung Cancer.

BACKGROUND: This study was conducted to investigate whether polymorphisms of glucose transporter 1 (GLUT1) gene are associated with the prognosis of patients with non-small cell lung cancer (NSCLC) after surgical resection. METHODS: Five single nucleotide polymorphisms (SNPs) in GLUT1 were investigated in a total of 354 patients with NSCLC who underwent curative surgery. The association of the SNPs with patients' survival was analyzed. RESULTS: Among the five SNPs investigated, two SNPs (GLUT1 rs3820589T > A and rs4658G > C) were significantly associated with OS in multivariate analyses. GLUT1 rs3820589T > A was associated with significantly better OS (adjusted hazard ratio [aHR] = 0.57, 95% confidence interval [CI] = 0.34-0.94, P = 0.03, under dominant model), and rs4658G > C was associated with significantly worse OS (aHR = 1.91, 95% CI = 1.09-3.33, P = 0.02, under recessive model). In the stratified analysis by tumor histology, the effect of these SNPs on OS was only significant in squamous cell carcinoma but not in adenocarcinoma. When the two SNPs were combined, OS decreased as the number of bad genotypes increased (Ptrend = 4 × 10-3). CONCLUSIONS: This study suggests that genetic variation in GLUT1 may be useful in predicting survival of patients with early stage NSCLC.

Intronic variant of EGFR is associated with GBAS expression and survival outcome of early-stage non-small cell lung cancer.

BACKGROUND: Genome-wide association studies have indicated that most of the currently identified disease and trait-associated single nucleotide polymorphisms (SNPs) are intronic or intergenic. RegulomeDB is a recently developed database that provides functional annotations for regulatory features of SNPs located in non-coding regions. We evaluated the potential regulatory SNPs in the EGFR gene region using RegulomeDB and their associations with prognosis after surgery in non-small cell lung cancer (NSCLC) patients. METHODS: A total of 698 patients with surgically resected NSCLC were enrolled and seven SNPs were selected based on the RegulomeDB database. All SNPs were genotyped using SEQUENOM MassARRAY iPLEX assay. RESULTS: Among the seven SNPs evaluated, rs9642391 (EGFR ivs19+2851C>G) was significantly associated with survival outcome (adjusted hazard ratio [HR] for overall survival = 0.70, 95% confidence interval [CI] 0.56-0.87, P = 0.001; adjusted HR for disease-free survival = 0.82, 95% CI 0.70-0.97, P = 0.02; under a codominant model). According to RegulomeDB, rs9642391C>G, which is located in intron 19 of EGFR, was predicted to influence the expression of GBAS but not EGFR. As predicted, rs9642391C>G was associated with GBAS (P = 0.024) but not EGFR messenger RNA expression in tumor tissues. CONCLUSION: In conclusion, our study provides evidence that rs9642391C>G in the intron of EGFR is associated with GBAS expression and survival outcomes of patients with surgically resected early-stage NSCLC.