Up‐regulation of p27(Kip1) Correlates Inversely with Anchorage‐independent Growth of Human Cancer Cell Lines

We examined the correlation between anchorage‐independent growth and cell cycle‐related molecules using 39 human cancer cell lines. They consisted of lung‐, colon‐, stomach‐, breast‐, ovarian‐, brain‐, renal‐ and melanoma‐derived cell lines. Their anchorage‐independent growth ability varied, but was not clearly related to the tissue of origin. There was a tendency for the levels of cyclin D1, cyclin E, cyclin A, p27, and p21 to show a tissue‐dependent expression pattern. Statistical analysis revealed an inverse correlation of the p27 level with anchorage‐independent growth (r=−0.456, P<0.01). Thus, the regulation of p27 is suggested to be linked to the anchorage independence of human cancer cells.