Anticancer Effect of Ursodeoxycholic Acid in Human Oral Squamous Carcinoma HSC-3 Cells through the Caspases

Abstract

Bear bile was used as a traditional medicine or tonic in East Asia, and ursodeoxycholic acid (UDCA) is the most important compound in bear bile. Further, synthetic UDCA is also used in modern medicine and nutrition; therefore, its further functional effects warrant research, in vitro methods could be used for the fundamental research of its anticancer effects. In this study, the apoptotic effects of UDCA in human oral squamous carcinoma HSC-3 cells through the activation of caspases were observed by the experimental methods of MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide) assay, DAPI (4’,6-diamidino-2-phenylindole) staining, flow cytometry analysis, RT-PCR (reverse transcription-polymerase chain reaction) assay and Western blot assay after HSC-3 cells were treated by different concentrations of UDCA. With 0 to 400 μg/mL UDCA treatment, UDCA had strong growth inhibitory effects in HSC-3 cells, but had almost no effect in HOK normal oral cells. At concentrations of 100, 200 and 400 μg/mL, UDCA could induce apoptosis compared to untreated control HSC-3 cells. Treatment of 400 μg/mL UDCA could induce more apoptotic cancer cells than 100 and 200 μg/mL treatment; the sub-G1 DNA content of 400 μg/mL UDCA treated cancer cells was 41.3% versus 10.6% (100 μg/mL) and 22.4% (200 μg/mL). After different concentrations of UDCA treatment, the mRNA and protein expressions of caspase-3, caspase-8, caspase-9, Bax, Fas/FasL (Fas ligand), TRAIL (TNF-related apoptosis-inducing ligand), DR4 (death receptor 4) and DR5 (death receptor 5) were increased in HSC-3 cells, and mRNA and protein expressions of Bcl-2 (B-cell lymphoma 2), Bcl-xL (B-cell lymphoma-extra large), XIAP (X-linked inhibitor of apoptosis protein), cIAP-1 (cellular inhibitor of apoptosis 1), cIAP-2 (cellular inhibitor of apoptosis 2) and survival were decreased. Meanwhile, at the highest concentration of 400 μg/mL, caspase-3, caspase-8, caspase-9, Bax, Fas/FasL, TRAIL, DR4, DR5, and IκB-α expression levels were the highest, and Bcl-2, Bcl-xL, XIAP, cIAP-1, cIAP-2, survival, and NF-κB expression levels were the lowest. These results proved that UDCA could induce apoptosis of HSC-3 cancer cells through caspase activation, and the higher concentration of UDCA had stronger effects in vitro. UDCA might be a good nutrient for oral cancer prevention.

Magnolol Triggers Caspase-Mediated Apoptotic Cell Death in Human Oral Cancer Cells through JNK1/2 and p38 Pathways

“…In this study, our results revealed that magnolol significantly repressed the cIAP-1 level in oral cancer cells. Pang et al reported that ursodeoxycholic acid induces apoptosis in HSC-3 cancer cells through caspase activation, which inhibits the translocation of NF-κB and the downregulation of c-IAP1 [27]. Thus, whether NF-κB signaling is involved in the magnolol-medicated downregulation of c-IAP1 in oral cancer, warrants further investigation.…”

Synergistic effect of ursodeoxycholic acid on the antitumor activity of sorafenib in hepatocellular carcinoma cells via modulation of STAT3 and ERK

“…Further studies are needed to investigate the effects of sorafenib and UDCA administration in vivo . In addition, not only the present study, but other UDCA-related preclinical studies use a relatively high concentration of UDCA as the IC 50 value ( 27 – 29 ). It would be more beneficial to reduce the concentration of UDCA to protect normal cells, unless the lower concentration reduces its antitumor efficacy.…”

XIAP (X-linked inhibitor of apoptosis)

“…Using tissue microarray, high XIAP expression was associated with a significant reduction in overall survival in a cohort of 193 squamous cell carcinomas (Frohwitter et al, 2017). HSC-3 cells treated with ursodeoxycholic acid (UDCA) and Ca9-22 cells treated with furano-1,2-naphthoquino (FNQ) and PP2 (a Src-specific inhibitor) presented XIAP downregulation (Lin et al, 2014;Pang et al, 2015).…”