Oncogenic transformation induced by the p110beta, -gamma, and -delta isoforms of class I phosphoinositide 3-kinase.

ABSTRACT: Class I phosphoinositide 3-kinase contains four isoforms of the catalytic subunit, p110alpha, -beta, -gamma, and -delta. At physiological levels of expression, the wild-type p110alpha isoform lacks oncogenic potential, but gain-of-function mutations and overexpression of p110alpha are correlated with oncogenicity. The p110beta, -gamma, and -delta isoforms induce transformation of cultured cells as wild-type proteins. This oncogenic potential requires kinase activity and can be suppressed by the target of rapamycin inhibitor rapamycin. The p110delta isoform constitutively activates the Akt signaling pathway; p110gamma activates Akt only in the presence of serum. The isoforms differ in their requirements for upstream signaling. The transforming activity of the p110gamma isoform depends on ra

SUBMITTER: Kang S 

PROVIDER: S-EPMC1360601 | biostudies-literature | 2006 Jan

REPOSITORIES: biostudies-literature