PIK3CB and neoplasm: We have examined the protein levels of the class I PI3K catalytic (p110α and p110β) and regulatory subunits (p85α and p85β), PTEN, Akt and phosphorylated Akt on serine 473 (p-S473-Akt) and threonine 308 (p-T308-Akt) in whole cell extracts of 7 endometrial cancer cell lines versus a non-tumor immortalized endometrial cell line (EM).