ITGB1 and posterior cortical atrophy: The exosomal proteins secreted by PCa cell lines are relatively high in tetraspanins such as CD9, CD82, CD61, heat shock protein (HSP) family HSP90, HSP70, and integrin proteins ITGA3, ITGB1, etc., and previous studies have confirmed these Proteins may play a role in the occurrence and development of tumors.