In summary, this study provides novel evidence that in a model of papillary thyroid carcinoma, miR-26a suppresses proliferation and colony formation efficiency, induces G2 cell cycle arrest, promotes cell apoptosis and inhibits tumor growth in vivo by targeting CKS2 and ultimately regulating the expression of cyclinB1, cdk1, bcl-xl and AKt. The gene discussed is BCL2L1; the disease is differentiated thyroid carcinoma.