Metabolism-Related Gene Expression in Circulating Tumor Cells from Patients with Early Stage Non-Small Cell Lung Cancer.

PURPOSE: Metabolic reprogramming is now characterized as one of the core hallmarks of cancer, and it has already been shown that the altered genomic profile of metabolically rewired cancer cells can give valuable information. In this study, we quantified three Metabolism-Related Gene (MRG) transcripts in the circulating tumor cells (CTCs) of early stage NSCLC patients and evaluated their associations with epithelial and EMT markers. EXPERIMENTAL DESIGN: We first developed and analytically validated highly sensitive RT-qPCR assays for the quantification of HK2, MCT1 and PHGDH transcripts, and further studied the expression of MRGs in CTCs that were isolated using a size-dependent microfluidic device (Parsortix, Angle) from the peripheral blood of: (a) 46 NSCLC patients at baseline, (b) 39/46 of these patients one month after surgery, (c) 10/46 patients at relapse and (d) 10 pairs of cancerous and adjacent non-cancerous FFPE tissues from the same NSCLC patients. Epithelial and EMT markers were also evaluated. RESULTS: MCT1 and HK2 were differentially expressed between HD and NSCLC patients. An overexpression of MCT1 was detected in 15/46 (32.6%) and 3/10 (30%) patients at baseline and at progression disease (PD), respectively, whereas an overexpression of HK2 was detected in 30.4% and 0% of CTCs in the same group of samples. The expression levels of all tested MRGs decreased in CTCs one month after surgery, but a significant increase was noticed at the time of relapse for PHGDH and MCT1 only. The expression levels of HK2 and MCT1 were associated with the overexpression of mesenchymal markers (TWIST-1 and VIM). CONCLUSION: An overexpression of MRGs was observed at a high frequency in the CTCs isolated from early NSCLC patients, thereby supporting the role of MRGs in metastatic processes. The glycolytic and mesenchymal subpopulation of CTCs was significantly predominant compared to CTCs that were glycolytic but not mesenchymal-like. Our data indicate that MRGs merit further evaluation through large and well-defined cohort studies.

DNA methylation analysis of tumor suppressor genes in liquid biopsy components of early stage NSCLC: a promising tool for early detection.

PURPOSE: Circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA) analysis represents a liquid biopsy approach for real-time monitoring of tumor evolution. DNA methylation is considered to be an early event in the process of cancer development and progression. The aim of the present study was to evaluate whether detection of DNA methylation of selected tumor suppressor genes in CTC and matched ctDNA provides prognostic information in early stage NSCLC. EXPERIMENTAL DESIGN: The methylation status of five selected gene promoters (APC, RASSFIA1, FOXA1, SLFN11, SHOX2) was examined by highly specific and sensitive real-time methylation specific PCR assays in: (a) a training group of 35 primary tumors and their corresponding adjacent non-cancerous tissues of early stage NSCLC patients, (b) a validation group of 22 primary tumor tissues (FFPEs) and 42 peripheral blood samples of early stage NSCLC patients. gDNA was isolated from FFPEs, CTCs (size-based enriched by Parsortix; Angle and plasma, and (c) a control group of healthy blood donors (n = 12). RESULTS: All five gene promoters tested were highly methylated in the training group; methylation of SHOX2 promoter in primary tumors was associated with unfavorable outcome. RASSFIA and APC were found methylated in plasma-cfDNA samples at 14.3% and 11.9%, respectively, whereas in the corresponding CTCs SLFN11 and APC promoters were methylated in 7.1%. The incidence of relapses was higher in patients with a) promoter methylation of APC and SLFN11 in plasma-cfDNA (P = 0.037 and P = 0.042 respectively) and b) at least one detected methylated gene promoter in CTC or plasma-cfDNA (P = 0.015). CONCLUSIONS: DNA methylation of these five gene promoters was significantly lower in CTCs and plasma-cfDNA than in the primary tumors. Combination of DNA methylation analysis in CTC and plasma-cfDNA was associated with worse DFI of NSCLC patients. Additional studies are required to validate our findings in a large cohort of early stage NSCLC patients.

Correlation of BRCA1, TXR1 and TSP1 mRNA expression with treatment outcome to docetaxel-based first-line chemotherapy in patients with advanced/metastatic non-small-cell lung cancer.

BACKGROUND: We explored the predictive significance of BRCA1, TXR1 and TSP1 expression in non-small-cell lung cancer (NSCLC) patients treated with docetaxel in association with cisplatin or gemcitabine. METHODS: To analyse BRCA1, TXR1 and TSP1 mRNA expression from microdissected primary tumours of 131 patients with stage IIIB (wet) and IV NSCLC, RT-qPCR was used. RESULTS: The mRNA levels of TXR1/TSP1 were inversely correlated (Spearman's test: -0.37; P=0.001). Low TXR1 mRNA levels were associated with higher response rate (RR; P=0.018), longer median progression-free survival (PFS; P=0.029) and median overall survival (mOS P=0.003), whereas high TSP1 expression was correlated with higher RR (P=0.035), longer PFS (P<0.001) and mOS (P<0.001). Higher BRCA1 mRNA expression was associated with higher RR (P=0.028) and increased PFS (P=0.021), but not mOS (P=0.4). Multivariate analysis demonstrated that low TXR1/high TSP1 expression was an independent factor for increased PFS (HR 0.49; 95% CI 0.32-0.76; P<0.001) and mOS (HR 0.37; 95% CI 0.2-0.58; P<0.001), whereas high BRCA1 expression was correlated with increased PFS (HR 0.53; 95% CI 0.37-0.78; P=0.001). CONCLUSIONS: These data indicate that TXR1/TSP1 and BRCA1 expression could be used for the prediction of taxanes' resistance in the treatment of NSCLC.

Cisplatin plus etoposide chemotherapy followed by thoracic irradiation and paclitaxel plus cisplatin consolidation therapy for patients with limited stage small cell lung carcinoma.

PURPOSE: To evaluate the efficacy and tolerance of a cisplatin plus etoposide regimen followed by thoracic radiotherapy (TRT) and paclitaxel plus cisplatin consolidation chemotherapy in patients with limited stage small cell lung cancer (SCLC). PATIENTS AND METHODS: Thirty-nine patients with limited SCLC were enrolled onto this study. Patients received three courses of cisplatin 75 mg/m2 i.v., day 1 and etoposide 100 mg/m2 i.v., days 1-3 (EP regimen), followed by TRT (45-56 Gy administered in 15 fractions), and three courses of paclitaxel 175 mg/m2 i.v., day 1 and cisplatin, as previously, on day 2 (PP regimen); cycles were repeated every 21 days. RESULTS: All patients were evaluable for toxicity and 34 for response. The overall response rate was 67% (CR: 26%; PR: 41%; intention-to-treat analysis) (95% CI: 53.0-84.2%). After a median follow-up period of 15 months, the median survival time was 15 months, the median time to tumor progression 8.3 months and the 1-year survival rate 53.8%. Grade 3/4 neutropenia occurred in 39% and 36% of patients receiving EP and PP regimens, respectively. The incidence of febrile neutropenia was 5% and 3% for EP and PP regimens, respectively. Other hematologic and non-hematologic toxicities were mild, with the exception of esophagitis occurring in 36% of patients during and/or immediately after radiotherapy. CONCLUSION: Consolidation therapy with PP after sequential EP and thoracic radiotherapy is feasible and well-tolerated; however, the efficacy results are comparable with those previously obtained in the same patients' population using a combination of EP and TRT.