The role of leukemia inhibitory factor receptor (LIFR), which is important in the signal transduction of the interleukin-6 cytokine family, is still undefined in clear cell renal cell carcinoma (ccRCC). Thus, we examined the function and mechanism of LIFR in ccRCC. Low LIFR expression correlated with a poor prognosis and an aggressive tumor phenotype. Moreover, integrated LIFR DNA and mRNA analysis revealed that promoter methylation and copy number variation contributed to the reduced LIFR expression. LIFR knockdown increased 786-O and Caki-2 cell invasion and migration. Notably, the Hippo pathway was highlighted as a potential downstream target of LIFR, where loss of LIFR inhibited the kinase activity of the pathway and increased the intracellular Yes-associated protein (YAP) level. Conversely, YAP inhibition impaired the LIFR-silencing promotion of cell migration, invasion, and cancer stem cell marker expression. Moreover, drug sensitivity analysis and the Cancer Cell Line Encyclopedia database revealed that LIFR-deficient cells had high sensitivity to a YAP inhibitor and to two other anticancer drugs (PHA-665752, PF2341066). Our study revealed that LIFR attenuates tumor metastasis by suppressing YAP expression, suggesting that LIFR may serve as a potential target for ccRCC treatment.
Keywords: Yes-associated protein; clear cell renal cell carcinoma; leukemia inhibitory factor receptor; metastasis.