RETRACTED: Promotion of tumor progression by exosome transmission of circular RNA circSKA3
William W. Du, Xiangmin Li, Jian Ma, Ling Fang, Nan Wu, Feiya Li, Preet Dhaliwal, Weining Yang, Albert Yee, Burton B. Yang
Abstract
, circSKA3-containing exosomes potentiated tumor development and invasion that were inhibited by blocking exosome transmission. The ascites isolated from tumor-bearing mice or breast cancer patients showed high levels of circSKA3 and integrin β1. Single-cell culture and single-cell PCR showed that circSKA3 was heterogeneously expressed, the cells expressing higher levels of circSKA3 had a higher potential to form large colonies. This property was similar to c-myc, but circSKA3 expression had no correlation with c-myc levels. The effects of circSKA3 on cell migration and invasion appeared to predominate c-myc functions. By releasing circSKA3-containing exosomes to cancer cells expressing lower levels of circSKA3, the large colonies could regulate the activities of small colonies, enhancing the tumor-forming capacity of the entire population. Thus, we provide evidence that the transmission of circular RNAs in tumor-derived exosomes may allow for the maintenance of advantageous invasive sub-clones in breast cancer.