CDK2 and colon carcinoma: However, depletion of cdk2 showed severe S-phase defects in several human cell lines (HeLa [cervical carcinoma], NCI-H1299 [non-small cell lung carcinoma], A375 & SKMEL5 [both melanoma]) [91], [92], [93], [94] but not in others (SW480 and HT-29 [both colon carcinoma]) [93], [95].