The over expression of genes possibly coding for proteins as markers of canine prostate tumor

Abstract Prostate cancer is the second leading cause of cancer related diseases among men. There already has been developed a marker protein for human prostate cancer known as Prostate specific antigen (PSA), which is used to detect prostate carcinoma in men. However the significant false positive rate is very high, which results in taking unnecessary painful biopsies from the prostate. Canine prostate cancer mostly resembles human androgen refractory poorly differentiated prostate cancer. That’s why we are trying to find a marker protein for the dog with a high sensitivity and which still has got the required specificity. In an American research they’ve found six protein peaks which could be a possible marker protein for canine prostate cancer by surface enhanced laser desorption ionization time of flight mass spectrometry (SELDI-TOF). [22] The following proteins have been identified to belong to the protein peaks: beta defensine 138, a fragment of kcne2,a fragment of mastcatory myosin heavy chain 16, a fragment of arginine_vasopressine precursor, nonhistone chromosomal protein HMG-17 en apolipoprotein cI precursor (apo-cI). Beta defensine 138 a fragment of arginine_vasopressine precursor didn’t appear to be expressed in the prostate in former research, so they haven’t been investigated in this research. Plasminogen appeared to be another protein which belonged to one of the peaks. The overexpression of these proteins in prostate carcinoma cell lines (CPA and ACE) were compared to a normal prostate cell line (CAPE) and a transitional cell line (k9TCC) in the dog. Apo-cI appeared to be the best possibility to serve as a marker protein. It had a slightly higher expression of this protein in CPA and ACE then in CAPE and K9TCC. In addition it was over expressed in the prostate carcinoma tissue pcai compared to other tissues. HMG-17 was also expressed very high, but this protein wasn’t specific for the prostate. The other proteins couldn’t be distinguished in expression between cell lines. Also there wasn’t a higher expression in pcai in these tissues. The difference in expression between the cell lines of apo-cI was to small to conclude it is the new canine marker for canine prostate carcinomas. There has to be done more research