Trichomonas vaginalis: a possible foe to prostate cancer

Abstract

Prostate cancer (PCA) is the most common malignancy in men in USA, and the role of Trichomonas vaginalis (T. vag) in the development of PCA is still controversial. Clonogenic assay, PCNA staining, TUNEL staining and caspase-3 activity assay were used to investigate the in vitro role of T. vag in human prostate cancer. We further investigated the possible molecular mechanisms using RT-PCR and immunohistochemical staining. Culture supernatant of T. vag inhibits growth of PC-3 prostate cancer cells, and this correlated with upregulation of p21. Culture supernatant of T. vag induced apoptosis of PC-3 cells, and this correlated with downregulation of Bcl-2. The growth inhibition effect of culture supernatant of T. vag is also demonstrated in another prostate cancer cell line DU145, suggesting that its effect is not specific to one prostate cancer cell line. Culture supernatant of T. vag inhibits growth of prostate cancer by inhibition of proliferation and promotion of apoptosis. Such a study might be helpful to address the association between PCA and infection of T. vag.

Inflammatory mediators of prostate epithelial cells stimulated with Trichomonas vaginalis promote proliferative and invasive properties of prostate cancer cells

“…MIF produced from Tv has been reported to increase the proliferation of PCa cells, 22 while the culture medium of Tv has also been shown to be cytotoxic to PCa cells. 42 Our previous studies Moreover, many studies have suggested that chemokines, such as CCL2 (MCP-1) and CXC including CXCL8 are involved in the invasiveness and metastasis of PCa. 49,50 CCL2, a member of the CC(β) chemokine family, is thought to recruit monocytes to sites of inflammation and is reported to induce activation of CCR2 in PCa epithelial cells as well as breast cancer and multiple myeloma cells, thus stimulating their migration and proliferation of cancer cells.…”

“…The association between Tv infection and PCa still remains controversial. MIF produced from Tv has been reported to increase the proliferation of PCa cells, while the culture medium of Tv has also been shown to be cytotoxic to PCa cells . Our previous studies reported that prostate epithelial cells cultured with live Tv were induced cytotoxicity with inflammatory responses .…”

IL‑33 notably inhibits the growth of colon cancer cells

“…Following the 72 h incubation, the HCT-116 cells were detached, manually counted and analyzed using a clonogenic survival assay kit (BioVision, Inc., Milpitas, CA, USA), as previously described ( 12 , 13 , 18 – 20 ). The final HCT-116 cell survival results of the study were expressed as a percentage of the total colonies that were counted within the control group.…”

“…A detailed method for PCNA staining has been previously described ( 12 , 13 , 18 – 20 ). To summarize, samples were incubated with 0.1% saponin (Sigma-Aldrich; Merck KGaA, Darmstadt, Germany) in 1% bovine serum albumin (Thermo Fisher Scientific, Inc.) and then incubated with polyclonal rabbit antibody for PCNA (sc-7907; dilution 1:100; Santa Cruz Biotechnology, Inc., Dallas, TX, USA) at room temperature for 1 h. The Avidin-Biotin Complex Immunoperoxidase system (Vector Laboratories, Inc., Burlingame, CA, USA) was used to amplify the immunoreactivity of the sample.…”

“…The PCNA antibody was replaced with an equal amount of normal rabbit IgG (sc-2027; Santa Cruz Biotechnology, Inc.) to establish a negative control, and it was then confirmed that the control slide was negative. Lastly, MetaMorph image analysis software (Molecular Devices LLC, Sunnyvale CA, USA) was used to measure the average immunostaining intensity and the results were expressed as an average integrated immunostaining intensity, which was described previously ( 12 , 13 , 18 – 20 ).…”