Genomic Landscape Survey Identifies SRSF1 as a Key Oncodriver in Small Cell Lung Cancer

Area of Science:

• Oncology
• Genomics
• Molecular Biology

Background:

• Small cell lung cancer (SCLC) is an aggressive malignancy with limited treatment options and poor patient survival rates.
• Previous genetic studies in SCLC have been limited, especially in Asian populations, leaving many potential driver genes undiscovered.
• Understanding the molecular landscape of SCLC is crucial for developing effective targeted therapies.

Purpose of the Study:

• To investigate the genomic and transcriptomic profiles of primary tumors from Chinese SCLC patients.
• To identify novel genes and pathways implicated in SCLC pathogenesis and progression.
• To evaluate the potential of identified genes as prognostic biomarkers and therapeutic targets for SCLC.

Main Methods:

• Whole exome sequencing (WES) and transcriptomic sequencing were performed on 99 primary SCLC tumors from Chinese patients.
• Analysis included identifying mutations, copy number alterations, and mRNA expression levels of key genes.
• Functional studies (in vitro and in vivo) were conducted to assess the role of identified genes in SCLC tumorigenicity, DNA repair, and chemo-sensitivity.

Main Results:

• TP53 and RB1 tumor suppressor genes were frequently dysregulated (82% and 62%, respectively), with 62% of patients showing combined mutation and/or copy number loss.
• Serine/Arginine Splicing Factor 1 (SRSF1) DNA copy number gain and mRNA over-expression were significantly associated with poor survival in both discovery and validation cohorts.
• Functional studies confirmed SRSF1's importance in SCLC tumorigenicity, DNA repair, and chemo-sensitivity.

Conclusions:

• TP53 and RB1 are commonly altered in Chinese SCLC patients, highlighting their central role in the disease.
• SRSF1 is a strong prognostic biomarker for SCLC, indicating its potential clinical utility.
• Targeting SRSF1 presents a promising strategy for personalized therapy development in SCLC.