Prognostic significance of the Cdk5 gene in breast cancer: an in silico study

Cyclin-dependent kinase 5 (Cdk5) functions as a tumor promoter in various types of cancer. Cdk5 is overexpressed in breast cancer patients. The prognostic significance of the Cdk5 gene and its expression in breast cancer were analyzed using various bioinformatic tools. Cdk5 gene expression in different breast cancer subtypes was analyzed using the Oncomine, UALCAN, and bcGenExMiner v4.2 websites. The correlation between Cdk5 mRNA expression and promoter methylation was established using TCGA datasets from the UCSC Xena and UALCAN websites. The relationship between Cdk5 promoter methylation and different clinicopathological parameters in breast cancer patients was determined using UALCAN. Cdk5 expression is associated with various clinicopathological parameters, such as estrogen receptor, progesterone receptor, the basal-like subtype, and triple-negative breast cancer, which was analyzed using bcGenExMiner v4.2. Kaplan–Meier plotter revealed high Cdk5 expression and poor survival in breast cancer patients. In addition, a list of genes that are coexpressed with Cdk5 in breast cancer was identified from the UALCAN website. From that list, we observed that Fas-activated serine/threonine kinase (FASTK) has a predominant positive correlation with Cdk5 in breast cancer. The UCSC Xena and bcGenExMiner v4.2 websites were used to confirm the correlation between Cdk5 and FASTK. Cdk5 overexpression might induce malignancies and is associated with a poor prognosis in breast cancer patients through FASTK. Therefore, Cdk5 might act as a biomarker to predict the prognosis of breast cancer.