Bone marrow mesenchymal stem cells-secreted exosomal microRNA-205-5p exerts inhibitory effect on the progression of liver cancer through regulating CDKL3

Objective: Bone marrow mesenchymal stem cells-derived exosomes (BMSCs-exo) carrying microRNA (miR) cargo have been emerged as a promising therapy for human cancers. Therein, we pivoted on the integral function of BMSCs-exo and miR-205-5p in liver cancer through mediation of cyclin-dependent kinase-like 3 (CDKL3). Methods: Patients with liver cancer were enrolled to collect the clinical tissue and determine miR-205-5p and CDKL3 expression. miR-205-5p expression in BMSCs was altered by transfection, and BMSCs-exo were extracted and co-cultured with LM3 cells. Meanwhile, LM3 cells were independently transfected with CDKL3 low or high expression vector. Since then, cell growth in vitro was observed, and the effect of exosomal miR-205-5p on tumor growth in vivo was further investigated. Results: miR-205-5p expression was low while CDKL3 was high in liver cancer. BMSCs-exo blocked cellular growth of liver cancer in vitro and in vivo. Overexpressing exosomal miR-205-5p decelerated the biological development of liver cancer cells while suppressing exosomal miR-205-5p had the contrary function in vitro and in vivo. Loss of CDKL3 impaired the malignant activities of liver cancer cells, and could even impair the protumor effects of down-regulated exosomal miR-205-5p. Conclusion: It is clearly concluded that BMSCs-secreted exosomal miR-205-5p exerts inhibitory effect on the progression of liver cancer through regulating CDKL3.