Mechanism of piRNA in bisphenol A-promoted invasion and migration of prostate cancer cells / 中华预防医学杂志

Objective: To investigate the regulatory mechanisms of piwi-interacting RNA (piRNA) in bisphenol A (BPA)-induced prostate cancer cell invasion and migration. Methods: The Cancer Genome Atlas (TCGA) data was used to analyze and screen for piRNAs with significantly increased expression in prostate cancer tissues. PC-3 cells were treated with different concentrations of BPA for 12, 24, and 48 h, respectively, and the 20% inhibitory concentration (IC20) was measured using a CCK-8 assay. The expression levels of piRNAs before and after BPA treatment were determined by reverse transcription-quantitative PCR. Target genes regulated by BPA and associated with prostate cancer were screened in the Comparative Toxicogenomics Database (CTD). Dual-luciferase reporter gene assay was performed to verify the relationship between piRNA and target genes, and the expression change of the piRNA target gene was detected by Western blotting. Cell migration and invasion assays were used to determine the effects of piRNA on the malignant phenotype of prostate cancer cells. Results: After treatment of PC-3 cells with 160 μmol/L BPA, the expression of piR-sno48 was most significantly increased (P<0.05). Transfection of piR-sno48 antagomir resulted in decreased expression of endogenous piR-sno48 and a significant increase in the expression of its target gene GSTP1 (P<0.05). However, the expression of GSTP1 did not change significantly in BPA-treated PC-3 cells after transfection with piR-sno48 antagomir (P>0.05). The dual-luciferase reporter gene confirmed that piR-sno48 inhibited the expression of GSTP1 by forming an inversely complementary sequence with the 3'-UTR of GSTP1. The Transwell assay results showed that treatment with BPA significantly increased the invasion and migration ability of prostate cancer cells (P<0.01), whereas piR-sno48 antagonists significantly inhibited the effects above (P<0.01). Conclusion: BPA promotes the invasion and migration of prostate cancer cells by upregulating the expression of piR-sno48 and suppressing the expression of GSTP1. Interfering with the expression of endogenous piR-sno48 may inhibit the malignant phenotype of prostate cancer cells caused by BPA.

Mechanism of piRNA in bisphenol A-promoted invasion and migration of prostate cancer cells / 中华预防医学杂志

Objective: To investigate the regulatory mechanisms of piwi-interacting RNA (piRNA) in bisphenol A (BPA)-induced prostate cancer cell invasion and migration. Methods: The Cancer Genome Atlas (TCGA) data was used to analyze and screen for piRNAs with significantly increased expression in prostate cancer tissues. PC-3 cells were treated with different concentrations of BPA for 12, 24, and 48 h, respectively, and the 20% inhibitory concentration (IC20) was measured using a CCK-8 assay. The expression levels of piRNAs before and after BPA treatment were determined by reverse transcription-quantitative PCR. Target genes regulated by BPA and associated with prostate cancer were screened in the Comparative Toxicogenomics Database (CTD). Dual-luciferase reporter gene assay was performed to verify the relationship between piRNA and target genes, and the expression change of the piRNA target gene was detected by Western blotting. Cell migration and invasion assays were used to determine the effects of piRNA on the malignant phenotype of prostate cancer cells. Results: After treatment of PC-3 cells with 160 μmol/L BPA, the expression of piR-sno48 was most significantly increased (P<0.05). Transfection of piR-sno48 antagomir resulted in decreased expression of endogenous piR-sno48 and a significant increase in the expression of its target gene GSTP1 (P<0.05). However, the expression of GSTP1 did not change significantly in BPA-treated PC-3 cells after transfection with piR-sno48 antagomir (P>0.05). The dual-luciferase reporter gene confirmed that piR-sno48 inhibited the expression of GSTP1 by forming an inversely complementary sequence with the 3'-UTR of GSTP1. The Transwell assay results showed that treatment with BPA significantly increased the invasion and migration ability of prostate cancer cells (P<0.01), whereas piR-sno48 antagonists significantly inhibited the effects above (P<0.01). Conclusion: BPA promotes the invasion and migration of prostate cancer cells by upregulating the expression of piR-sno48 and suppressing the expression of GSTP1. Interfering with the expression of endogenous piR-sno48 may inhibit the malignant phenotype of prostate cancer cells caused by BPA.

Endoplasmic reticulum stressed hepatocellular carcinoma promotes macrophage M2 polarization through exosome-toll-like receptor 4 pathway / 中国药理学通报

Aim To explore the effect of endoplasmic reticulum (ER) stress-related exosomes derived from hepatocellular carcinoma (HCC) cells on the M2 polarization of macrophages via Toll-like receptor 4 (TLR4) and the underlying mechanism. Methods Western blot experiments were conducted to evaluate the GRP78 levels in HCC tissues and HCC cells with or without pre-treatment of tunicamycin and the identification of the isolated exosomes. Immunohistochemical staining was also employed to detect the expression of GRP78 in HCC tissues. Immunofluorescence was used to confirm the effective absorbance of exosomes by macrophages. Flow cytometry ( FCM ) , Western blot and CBA kit were used to detect M2 polarization-asso ciated markers and the expression of TLR4 on macrophages. Affymetrix gene chip and bioinformatics analy-sis were used to screen the differential expression of mRNA in macrophages stimulated by ER stressed-relat- ed exosomes and TLR4 expression. Results In clinical samples, GRP78 expression in liver cancer tissues was higher than that in the adjacent tissues. In cell experiments, tunicamycin (2.5 jxmol • L"1 ) treatment for 24 hours in HCC cells could significantly increase the expression of ER stress marker protein GRP78 compared with control group. Western blot showed that HCC cell-derived exosomes positively expressed exosom- al marker proteins,such as CD63,TSG101 and HSP70, and negatively expressed Calnexin. Interestingly, HSP70-enriched exosomes released by ER-stressed HCC cells were observed. Laser confocal microscopy found that exosomes could be effectively taken up by RAW264.7 macrophages. Flow cytometry and Western blot further indicated that ER stress-related exosomes could significantly up-regulate the expression of CD206, transformed growth factor-beta (TGF-p) and arginase-1 (Arg-1) in macrophages. Meanwhile, these exosomes could promote the secretion of IL-6 and IL- 10,and up-regulate the expression of TLR4 in macrophages. Conclusions ER stressed-HCC cells could promote macrophage M2 polarization by releasing HSP70-enriched exosomes and activating TLR4 signaling.