Results Elevated Mcl 1 expression is linked with PCa progress and bone metastasis To investigate the clinical significance of Mcl 1 in PCa progression, immunohistochemical analyses were carried out to find out the expression of Mcl 1 in the human PCa tissue microarray with matched typical adjacent tissue and bone metastatic bone specimens We defined tumors with Gleason score 2 6 also differentiated Gleason score 7 as inter mediately differentiated and Gleason score 8 10 as poorly differentiated Mcl one immunointensity was greater from typical tissues to properly differentiated cancer and even further elevated in higher grade PCa, while the difference involving Mcl 1 intensity in intermediate and poorly differentiated cancers was not statistically considerable Intriguingly, Mcl 1 staining in bone metastatic tumors was remarkably increased pared to that in either intermediate or poorly differentiated PCa These data corre lated elevated Mcl 1 expression to clinical PCa progres sion, specifically bone metastasis.
Mcl 1 is often a survival issue in human PCa cells We now have established a few lines of human PCa models that closely mimic the selleck chemical clinical progression of PCa bone metastasis, such as the ARCaP model When inoculated both orthotopically or intracardially, ARCaPM cells are capable of metastasizing sponta neously to bone and soft tissues, forming mixed osteo blastic and osteolytic lesions in mouse skeleton The ARCaPM C2 subclone, derived from metastatic bone tissues immediately after two rounds of intracardiac injection of ARCaPM cells in athymic mice, varieties pre dictable metastases to bone, adrenal gland as well as other soft tissue with increased propensity and shorter latency Reverse transcription PCR and immunoblotting analyses located that Mcl one was sub stantially expressed by ARCaPM cells, and more improved in ARCaPM C2 cells Similarly, greater Mcl 1 expression was observed in metastatic C4 two and C4 2B cells when pared to their par ental, androgen dependent human PCa cell line LNCaP These final results recommended a achievable association among Mcl 1 expression and inva sive phenotypes of PCa cells.
To examine the function of Mcl 1 in PCa cell survival, a Mcl 1 compact interfering RNA was transfected into ARCaPM cells. siRNA treatme nt successfully inhib ited Mcl 1 expression and considerably decreased ARCaPM cell viability by 36% right after 72 h Annexin V staining by fluorescence activated cell sorting analysis showed the PHA-665752 Mcl 1 siRNA induced apopto sis in 24.