TNFRSF13B is a potential contributor to prostate cancer

Abstract

Background: Immunodeficiencies are genetic diseases known to predispose an individual to cancer owing to defective immunity towards malignant cells. However, the link between immunodeficiency and prostate cancer progression remains unclear. Therefore, the aim of this study was to evaluate the effects of common genetic variants among eight immunodeficiency pathway-related genes on disease recurrence in prostate cancer patients treated with radical prostatectomy.

Methods: Genetic and bioinformatic analyses on 19 haplotype-tagging single-nucleotide polymorphisms in eight immunodeficiency pathway-related genes were conducted in 458 patients with prostate cancer after receiving radical prostatectomy. Furthermore, the TNFRSF13B was knocked down in 22Rv1 and PC-3 human prostate cancer cell lines via transfecting short hairpin RNAs and cell proliferation and colony formation assays were performed. The molecular mechanisms underlying the effects of TNFRSF13B were further explored by microarray gene expression profiling.

Results: TNFRSF13B rs4792800 was found to be significantly associated with biochemical recurrence even after adjustment for clinical predictors and false discovery rate correction (adjusted hazard ratio 1.78, 95% confidence interval 1.16-2.71, p = 0.008), and the G allele was associated with higher TNFRSF13B expression (p = 0.038). Increased TNFRSF13B expression suggested poor prognosis in four independent prostate cancer datasets. Furthermore, silencing TNFRSF13B expression resulted in decreased colony formation of 22Rv1 and PC-3 cells through modulating the cell cycle and p53 signalling pathways.

Conclusions: The present study suggests the potential role of immunodeficiency pathway-related genes, primarily TNFRSF13B, in prostate cancer progression.

Keywords: Biochemical recurrence; Biomarker; Immunodeficiency; Prognosis; Prostate cancer; TNFRSF13B.

Fig. 1

Kaplan–Meier survival analysis for biochemical recurrence-free survival based on TNFRSF13B rs4792800 genotypes. Numbers in parentheses indicate the number of patients. BCR biochemical recurrence, RP radical prostatectomy

Fig. 2

Meta-analysis of the correlation between rs4792800 and TNFRSF13B expression in 7893 tissue samples from the Genotype-Tissue Expression dataset

Fig. 3

Meta-analysis of four studies evaluating the hazard ratio of high compared with low expression levels of TNFRSF13B for prostate cancer prognosis. SE standard error, IV inverse variance, CI confidence interval

Fig. 4

Silencing TNFRSF13B expression decreases the colony formation potential of human prostate cancer cells. A Silencing TNFRSF13B expression with short hairpin RNAs (shRNAs) decreased protein expression in the human prostate cancer 22Rv1 and PC-3 cell lines. Cells were transfected with an empty vector or TNFRSF13B shRNAs (shTNFRSF13B) using lentivirus, and TNFRSF13B protein expression in cells was examined via western blotting. B TNFRSF13B knockdown decreases the proliferation of 22Rv1 cells but not of PC-3 cells. Cells stably expressing an empty vector or shTNFRSF13B were seeded in 96-well plates and allowed to proliferate for four days. Cell proliferation was then estimated using MTT assay. C TNFRSF13B knockdown decreases the colony formation potential of both 22Rv1 and PC-3 cells. Cells stably expressing an empty vector or shTNFRSF13B were seeded in 6-well plates and allowed to grow for three weeks. The colonies were fixed and counted using the ImageJ software. Data are represented as mean ± standard deviation values from three independent experiments. *p < 0.05

Fig. 5

Gene expression profiling identified that cell cycle-related pathways are altered after TNFRSF13B short hairpin RNA (shTNFRSF13B) transfection in human prostate cancer cells. A Venn diagram analysis of all significantly differentially expressed (SDE) genes in 22Rv1 and PC-3 cells, displayed as the number of genes. B KEGG pathway analysis of 190 common SDE genes expressed in both 22Rv1 and PC-3 cells. C Reactome pathway analysis of 190 common SDE genes expressed in both 22Rv1 and PC-3 cells. D Knockdown of TNFRSF13B resulted in an increase of p53 protein expression in 22Rv1 cells, but no p53 expression was observed in PC-3 cells. Cells were transfected with an empty vector or shTNFRSF13B, and p53 protein expression was examined via western blotting. The representative western blot was obtained from three independent experiments

Fig. 6

Genetic and functional analyses identify the role of TNFRSF13B in prostate cancer progression. Homozygous carriers of the minor G allele of TNFRSF13B rs4792800 were identified to be significantly associated with an increased risk of biochemical recurrence in 458 patients with prostate cancer after receiving radical prostatectomy. Further gene expression profiling revealed that silencing TNFRSF13B can inhibit prostate cancer cell growth and colony formation through modulating the cell cycle and p53 signalling pathways