Exosomes-coated bcl-2 siRNA inhibits the growth of digestive system tumors both in vitro and in vivo

The therapeutic application of small interfering RNA is limited by the lack of an effective delivery system to tumors. In the present study, an efficient approach to deliver siRNA to cancer cells using exosome system was developed. Exosomes were isolated from bovine milk and exosomes-coated bcl-2 siRNA (exosiBcl-2) was synthesized using ultrasonic approach. The anticancer effect of exsosiBcl-2 was studied by Confocal microscopy, flow cytometry, scratch wound healing and Transwell experiments, RT-qPCR and Western blot approaches, etc. Xenograft nude mice tumor model was performed to check the antitumor activity of exosiBcl-2 in vivo. ExosiBcl-2 can cross the cell membrane efficiently and inhibit the growth of cancer cells. ExosiBcl-2 treatment led to apoptosis and dramatic inhibition of migration and invasion of cancer cells via downregulating metastatic related genes. In vivo study revealed that exosiBcl-2 inhibited the tumor growth significantly in nude mice. ExosiBcl-2 has potential to be developed as a novel anticancer agent.