The expression of genes coding for putative plasma protein markers for canine prostate carcinoma in normal and malignant prostate tissue

Abstract

Just like humans the dog has the ability to develop prostate carcinomas spontaneously. In humans the protein PSA is used as a biomarker for detection of prostatic disorders and for detection of prostatic carcinomas in an early stage. In the dog no such biomarkers for detection of prostatic disease are known. According to a manuscript from the Chand Khanna Group in Bethesda who depicted by proteomic approach certain genes as possibilities for certain peaks measured by surface enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS) on serum from dogs with prostate carcinomas, proteins for these research were chosen. These proteins are Apo-C-I, AVP precursor, ß-defensin 138, HMG-17, KCNE2 and masticatory myosin heavy chain 16. The aim of this research was to verify the expression of the genes encoding these proteins in normal prostates and prostate carcinomas of the dog and if those genes were up regulated in the prostate carcinomas. The results are obtained first by validation of quantitative RT-PCR on different tissues in which these genes normally are expressed. Thereafter the quantitative RT-PCR was done on amplified RNA obtained by micro dissection from normal prostates and canine prostate carcinomas. It is possible that the genes encoding Apo-C-I, HMG-17, KCNE2 and MYH16 are expressed in normal prostate tissues and prostate carcinomas. Indications are found that the gene encoding Apo-C-I could be up regulated in prostate carcinomas and therefore this is the most reliable protein for further investigation for a potential biomarker for prostate carcinomas in the dog. The fact that Apo-C-I is a possible marker can be reasoned because of the role of apolipoproteins in fat metabolism. Phospholipidogenesis de novo is required in the membranogenesis of tumor cells. In the human prostate Apolipoprotein E (ApoE) has a unique function in the prostate together with fatty acid synthase (FAS) in carcinogenesis and tumor progression.