PD0332991/Paclitaxel in Advanced Breast Cancer

breast cancer, patient must have histologically or cytologically-confirmed metastatic, any er, pr or her2 status is allowed., tumor must express retinoblastoma (rb) protein, defined as, any measurable staining by immunohistochemistry on the invasive tumor component, <3 prior cytoxic chemotherapy regimens for metastatic disease., performance status of 0-1 on the eastern cooperative oncology group performance scale and life expectancy > 3 months., patient must have evaluable disease. measureable disease is not required., the subject has adequate organ function, interventional, phase1