Cell-by-Cell: Unlocking Lung Cancer Pathogenesis

Whole Exome Sequencing reveals clinically important pathogenic mutations in DNA repair genes across lung cancer patients

Lung cancer remains a substantial health challenge, with distinct genetic factors influencing disease susceptibility and progression. This study aimed to decipher the landscape of DNA repair gene mutations in Pakistani lung cancer patients using Whole Exome Sequencing (WES) and to investigate their potential functional implications through downstream analyses. WES analysis of genomic DNA from 15 lung cancer patients identified clinically important pathogenic mutations in 6 DNA repair genes, including, BReast CAncer gene 1 (BRCA1), BReast CAncer gene 2 (BRCA2), Excision Repair Cross Complementing rodent repair deficiency, complementation group 6 (ERCC6), Checkpoint Kinase 1 (CHEK1), mutY DNA glycosylase (MUTYH), and RAD51D (RAD51 Paralog D). Kaplan-Meier (KM) analysis showed that pathogenic mutations in BRCA1, BRCA2, ERCC6, CHEK1, MUTYH, and RAD51D genes were the prognostic biomarkers of worse OS in lung cancer patients. To explore the functional impact of these mutations, we performed Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and Immunohistochemistry (IHC) analyses. Our results revealed a down-regulation in the expression of the mutated genes, indicating a potential link between the identified mutations and reduced gene activity. This down-regulation could contribute to compromised DNA repair efficiency, thereby fostering genomic instability in lung cancer cells. Furthermore, targeted bisulfite sequencing analysis was employed to assess the DNA methylation status of the mutated genes. Strikingly, hypermethylation in the promoters of BRCA1, BRCA2, ERCC6, CHEK1, MUTYH, and RAD51D was observed across lung cancer samples harboring pathogenic mutations, suggesting the involvement of epigenetic mechanism underlying the altered gene expression. In conclusion, this study provides insights into the genetic landscape of DNA repair gene mutations in Pakistani lung cancer patients. The observed pathogenic mutations in BRCA1, BRCA2, ERCC6, CHEK1, MUTYH, and RAD51D, coupled with their down-regulation and hypermethylation, suggest a potential convergence of genetic and epigenetic factors driving genomic instability in lung cancer cells. These findings contribute to our understanding of lung cancer susceptibility and highlight potential avenues for targeted therapeutic interventions in Pakistani lung cancer patients.

Platelet-lymphocyte ratio is a prognostic marker in small cell lung cancer-A systemic review and meta-analysis

Aim

The aim of this study was to evaluate the relationship between platelet-lymphocyte ratio (PLR) and prognosis in small cell lung cancer (SCLC) patients.

Method

A comprehensive search was carried out to collect related studies. Two independent investigators extracted the data of hazard ratio (HR) and 95% confidence interval (CI) for overall survival (OS) or progression-free survival (PFS). A random-effect model was applied to analyze the effect of different PLR levels on OS and PFS in SCLC patients. Moreover, subgroup analysis was conducted to seek out the source of heterogeneity.

Results

A total of 26 articles containing 5,592 SCLC patients were included for this meta-analysis. SCLC patients with a high PLR level had a shorter OS compared with patients with a low PLR level, in both univariate (HR = 1.56, 95% CI 1.28-1.90, p < 0.0001) and multivariate (HR = 1.31, 95% CI 1.08-1.59, p = 0.007) models. SCLC patients with a high PLR level had a shorter PFS compared with patients with a low PLR level, in the univariate model (HR = 1.71, 95% CI 1.35-2.16, p < 0.0001), but not in the multivariate model (HR = 1.17, 95% CI 0.95-1.45, p = 0.14). Subgroup analysis showed that a high level of PLR shortened OS in some subgroups, including the Asian subgroup, the younger subgroup, the mixed-stage subgroup, the chemotherapy-dominant subgroup, the high-cutoff-point subgroup, and the retrospective subgroup. PLR level did not affect OS in other subgroups.

Conclusion

PLR was a good predictor for prognosis of SCLC patients, especially in patients received chemotherapy dominant treatments and predicting OS.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022383069.

Salvianolic acid B from Salvia miltiorrhiza bunge: A potential antitumor agent

Salvia miltiorrhiza Bunge (Lamiaceae) is a perennial herb widely found in China since ancient times with a high economic and medicinal value. Salvianolic acid B (Sal-B) is an important natural product derived from Salvia miltiorrhiza and this review summarizes the anticancer activity of Sal-B. Sal-B inhibits tumor growth and metastasis by targeting multiple cell signaling pathways. This review aims to review experimental studies to describe the possible anticancer mechanisms of Sal-B and confirm its potential as a therapeutic drug.

The Third Joint Meeting on Lung Cancer of the FHU OncoAge (University Côte d'Azur, Nice, France) and the University of Texas MD Anderson Cancer Center (Houston, TX, USA). Understanding New Therapeutic Options and Promising Predictive Biomarkers for Lung Cancer Patients

We are proud and happy to present this Special Issue, a follow-up to the third joint meeting on lung cancer of the FHU OncoAge (University Côte d'Azur, Nice, France) and the University of Texas MD Anderson Cancer Center (Houston, TX, USA), which was held virtually on 4 October 2021 [...].