SOX7 is down-regulated in lung cancer

Area of Science:

• Genetics and Molecular Biology
• Oncology
• Cancer Genomics

Background:

• SOX7 is a transcription factor within the SOX family.
• The specific role of SOX7 in lung cancer pathogenesis remains largely unexplored.

Purpose of the Study:

• To investigate the function of SOX7 in non-small cell lung cancer (NSCLC).
• To determine the copy number alterations and expression patterns of SOX7 in NSCLC.
• To evaluate the impact of SOX7 modulation on NSCLC cell behavior.

Main Methods:

• Whole genomic copy number analysis using SNP-Chip platform on NSCLC cell lines and patient samples with EGFR mutations.
• Quantification of SOX7 gene expression in NSCLC samples and cell lines.
• Forced expression of SOX7 in NSCLC cell lines to assess its functional effects.

Main Results:

• Copy number (CN) alterations in Asian, non-smoking EGFR-mutant NSCLC showed similarities to The Cancer Genome Atlas (TCGA) collection, with some unique regions.
• The SOX7 gene was found to be homozygously deleted in 1 NSCLC cell line and heterozygously deleted in 2 others.
• SOX7 expression was significantly downregulated in 80% of NSCLC cell lines and 92% of NSCLC samples compared to normal lung tissue (p=0.0006).
• Forced expression of SOX7 markedly reduced cell growth and enhanced apoptosis in NSCLC cell lines.

Conclusions:

• SOX7 functions as a novel tumor suppressor gene in non-small cell lung cancer.
• Silencing or deletion of SOX7 is a common event in the majority of NSCLC cases.
• Restoration of SOX7 expression has therapeutic potential for NSCLC.