CDKN1B and cancer: Furthermore, CAF-secreted exosomes carry various microRNA that change cancer cell behaviour, i.e., CAF-exosomes are rich in miR-196a, which targets ING5 and CDKN1B mRNA, resulting in the reduction of ING5 and p27KIP1, CDK2/4 and cyclin D1/E activity, respectively, and they are deprived of miR-34a and miR-3188 that leads to the activation of AKT/β-catenin and Bcl-2 and their downstream pathways [122,224,225,226,245].