Alterations of p16-pRb Pathway and Chromosome Locus 9p21–22 in Sporadic Invasive Breast Carcinomas

The p16-pRb pathway represents a vital cell-cycle checkpoint. In the present study we investigated the alterations of this G1-phase protein pathway using immunohistochemical and molecular methods in a series of 55 breast carcinomas and correlated the findings with clinicopathological features of the patients. Furthermore, we examined its relationship with the status of the chromosomal region 9p21–22 performing a deletion map analysis because there are indications that, in addition to CDKN2and MTS2/p15INK4Btumor suppressor genes (TSGs), this area harbors other TSG(s).