A preliminary study of genes related to concomitant chemoradiotherapy resistance in advanced uterine cervical squamous cell carcinoma

Background Tumor intrinsic chemoradiotherapy resistance is the primary factor in concomitant chemoradiotherapy failure in advanced uterine cervical squamous cell carcinoma. This study aims to identify a set of genes and molecular pathways related to this condition.

Methods Forty patients with uterine cervical squamous cell carcinoma in International Federation of Gynecology and Obstetrics stage IIb or IIIb, treated with platinum-based concomitant chemoradiotherapy between May 2007 and December 2012, were enrolled in this trial. Patients included chemoradiotherapy resistant (n=20) and sensitive (n=20) groups. Total RNA was extracted from fresh tumor tissues obtained by biopsy before treatment and microarray analysis was performed to identify genes differentially expressed between the two groups.

Results Microarray analysis identified 108 genes differentially expressed between concomitant chemoradiotherapy resistant and sensitive patients. Functional pathway cluster analysis of these genes revealed that DNA damage repair, apoptosis, cell cycle, Map kinase signal transduction, anaerobic glycolysis and glutathione metabolism were the most relevant pathways. Platelet-derived growth factor receptor alpha (PDGFRA) and protein kinase A type 1A (PRKAR1A) were significantly upregulated in the chemoradiosensitive group, while lactate dehydrogenase A (LDHA), bcl2 antagonist/killer 1 (BAK1), bcl2/adenovirus E1B 19 kDa interacting protein 3 (BNIP3), single-strand-selective monofunctional uracil-DNA glycosylase 1 (SMUG1), and cyclin-dependent kinase 7 (CDK7) were upregulated in the chemoradiotherapy resistant group.

Conclusion We have identified seven genes that are differentially expressed in concomitant chemoradiotherapy resistant and sensitive uterine cervical squamous cell carcinomas, which may represent primary predictors for this condition.