CD44 and neoplasm: The intensity of immunohistochemical staining of CD44, CD147, CD31, Ki-67, Caspase-3(active), TUNEL in tumor xenografts from PC-3M-luc, PC-3M-luc-scr, PC-3M-luc-CD44-KD and PC-3M-luc-CD147-KD with DTX and/or veihicle treatment.