Abstract:
Epithelial-mesenchymal transition (EMT) features are associated with pathological severity in the progression and metastasis of various cancer types, including bile duct cancer (BDC). Our previous study demonstrated that ursodeoxycholic acid (UDCA) blocked the EGFR-MAPK signaling pathway and inhibited the invasion of BDC cells. The present study was performed to determine whether UDCA inhibits EMT and promotes the expression of E-cadherin to inhibit the invasion and aggressiveness of BDC. In addition, the present study aimed to confirm that the primary mechanism of inhibition of EMT by UDCA is related to the EGFR axis. Human extrahepatic BDC cells were cultured. The effect of UDCA on cell proliferation was evaluated using MTT assays. A cell death ELISA kit was used to measure apoptosis, and western blot assays or immunofluorescence staining assays measured the expression levels of various target proteins. The mRNA expression of Slug and ZEB1 was evaluated via reverse transcription-quantitative PCR. The invasiveness of BDC cells was estimated by invasion assays and western blot assays for focal adhesion kinase (FAK). UDCA inhibited the proliferation of BDC cells as effectively as gefitinib (an EGFR inhibitor), and the combination of UDCA and gefitinib revealed an additive effect on the proliferation of cells. UDCA and gefitinib induced apoptosis, and the combination of UDCA and gefitinib demonstrated an additive effect on apoptosis in BDC cells. UDCA restored the E-cadherin expression inhibited by EGF and suppressed N-cadherin expression increased by EGF as effectively as gefitinib. UDCA suppressed the Slug and ZEB1 mRNA expression induced by EGF in BDC cells. UDCA suppressed the invasiveness of BDC cells and FAK expression linked to the invasiveness of BDC. In conclusion, UDCA enhanced E-cadherin expression and suppressed N-cadherin expression through inhibition of the EGF-EGFR axis, contributing to the inhibition of EMT and invasiveness in BDC cells. Therefore, UDCA may be applied as an adjuvant or palliative antineoplastic agent and as a therapeutic option to enhance the effect of other chemotherapeutics.
摘要:
上皮-间质转化(EMT)特征与各种癌症类型的进展和转移的病理严重程度有关。包括胆管癌(BDC)。我们先前的研究表明熊去氧胆酸(UDCA)阻断EGFR-MAPK信号通路并抑制BDC细胞的侵袭。进行本研究以确定UDCA是否抑制EMT并促进E-cadherin的表达以抑制BDC的侵袭和侵袭性。此外,本研究旨在证实UDCA抑制EMT的主要机制与EGFR轴有关。培养人肝外BDC细胞。使用MTT测定评价UDCA对细胞增殖的影响。细胞死亡ELISA试剂盒用于测量细胞凋亡,和蛋白质印迹测定或免疫荧光染色测定测量各种靶蛋白的表达水平。通过逆转录-定量PCR评估Slug和ZEB1的mRNA表达。BDC细胞的侵袭力通过侵袭测定和粘着斑激酶(FAK)的蛋白质印迹测定来估计。UDCA与吉非替尼(EGFR抑制剂)一样有效地抑制BDC细胞的增殖,UDCA和吉非替尼的组合显示了对细胞增殖的累加作用。UDCA和吉非替尼诱导细胞凋亡,UDCA和吉非替尼的组合对BDC细胞凋亡具有累加作用。UDCA与吉非替尼一样有效地恢复了EGF抑制的E-钙粘蛋白表达,并抑制了EGF增加的N-钙粘蛋白表达。UDCA抑制了EGF诱导的BDC细胞中Slug和ZEB1mRNA的表达。UDCA抑制BDC细胞的侵袭性,FAK表达与BDC的侵袭性有关。总之,UDCA通过抑制EGF-EGFR轴来增强E-cadherin表达和抑制N-cadherin表达,有助于抑制BDC细胞中的EMT和侵袭性。因此,UDCA可以作为佐剂或姑息性抗肿瘤剂和作为治疗选择应用以增强其他化疗剂的效果。