Table 1.
Selected microbial factors and its role in prostate cancer development.
| Microbe | Urine/Stool/PC Tissue | Assay | Mechanism of Action | Outcome | Citation |
|---|---|---|---|---|---|
| Propionibacterium spp. | PC tissue | whole genome sequencing; massive ultradeep pyrosequencing; PCR | Chronic inflammation | Increased prevalence | [21,22,24] |
| Staphylococcus spp. | |||||
| Proteobacterium spp. | |||||
| Mycoplasma genitalium | |||||
| Anaerococcus lactolyticus Varibaculum cambriense | Urine | NGS; PCR | Chronic inflammation | Increased prevalence | [15] |
| Actinobaculum schaalii | |||||
| Propionimicrobium lymphophilum | |||||
| Ureaplasma spp. | |||||
| Ochrobactrum spp. | EPS | PCR-DGGE | Immune dysfunction? | Cancer (stage) progression | [16] |
| Helicobacter pylori | PC tissue | PCR; NGS | cagA integration in PPP1R9A and NCAM | Increased prevalence | [17] |
| HPV18 | PC tissue | PCR; NGS | Viral DNA integration into FAM111B and KCNC4, intergenic and intronic regions | Increased prevalence | [17] |
| KSHV | PC tissue | PCR; NGS | Viral DNA integration into ORF75, intergenic and intronic regions | Increased prevalence | [17] |
| Gardnerella vaginalis | PC tissue | RNA-sequencing | Downregulation of immune-associated genes (LPCAT2, TLR3, TGFB2) | Increased tumor progression | [18] |
| Listeria monocytogenes | PC tissue | RNA-sequencing | Increased ROS production and cytokines release, induction of cytotoxic T-cells’ response, | Decreased Gleason score | [18] |
| Pseudomonas spp. | PC tissue | DNA and RNA sequencing | Increased small RNAs expression | Reduced progression to metastatic disease | [19] |
| Bacteroides massiliensis | Stool | NGS | Increased free estrogens in bloodstream due to β-glucuronidases | Increased prevalence | [20] |
| Trichomonas vaginalis * | human prostate cancer cell lines (PC3, DU145, and LNCaP) | Quantitative RT PCR, Reverse transcriptase PCR, Western Blot, ELISA Immunofluorescence assay | Increased IL-6 and CCL2 and CXCL8 production; induction of M2 macrophage polarization | Neoplastic progression | [44] |
| Chlamydia trachomatis * | human prostate cancer epithelial cell line (CWR-R1) | Quantitative RT PCR, Immunofluorescence assay | Increased mRNA expression for IL-6 and FGF-2 | Chemoresistance and progression to metastatic disease | [46] |
*—basic science studies; PC—prostate cancer; PCR—polymerase chain reaction; NGS—next-generation sequencing; EPS—expressed prostatic secretions; RT-PCR—real-time polymerase chain reaction; PCR-DGGE—polymerase chain reaction-denaturing gradient gel electrophoresis.