PPARD and cholangiocarcinoma: In contrast to our results, other experimental works reported that the activation of PPARβ/δ by GW501516 significantly increased the migration and invasion of highly metastatic melanoma cells through the upregulation of Snail expression (a transcriptional repressor of cdh1 gene encoding for the E-cadherin) and the decrease of E-cadherin expression [44], enhanced human cholangiocarcinoma cell proliferation [45], or enhanced colorectal cancer in APC mutated mice [46].