Now a day's pets, dogs & cats form an important part of society and their health care have gain much popularity among owners. The hazardous radiations, along with other ailments cause different cancers in them which are the most fatal diseases. This increase in cancer prevalence is also related to animals living to increasingly older ages due to better nutrition, vaccination and health care provided to them. In order to provide proper treatment and care to these animal cancer patients, it is important to gather knowledge about the genes involve in causing them. There are many genes which regulate the cell cycle progression, cell proliferation and cell differentiation. Here in this study we have tried to understand this dreadful disease at molecular level. And hoping the knowledge gain through this would help in providing better treatment in future, not only to pets but also to humans. Dogs and humans share anatomical and physiological similarities, and a large number of cancers are diagnosed and managed to some extent in dogs annually. More importantly the basic biology of cancer in dogs is analogous to human cancers. According to an estimate every fourth dog suffers with cancer.
The deregulation and mutations in proto-oncogenes are the subjects under study. One such proto-oncogene is Myc, whose translated protein act as a transcription factor and regulates the expression of various genes. Myc protein binds DNA at specific sites, i-e e-box sequence and initiates the transcription of other genes, and controls their expression. Myc is assumed to regulate 15% of all cellular genes. Elevated expression of Myc is spotted in about 70% of all cancers.
The sampling was done from pet dogs and cats, belonging to different breeds with diagnosed tumor type, from the pet centre of university of veterinary and animal sciences, Lahore and various private pet clinics. 3-5 ml blood was collected aseptically and genomic DNA was extracted from blood using inorganic extraction method & its quantity was checked by NanoDrop spectophotometer. Four primer sets were designed to amplify protein coding region of Myc gene. After amplification through PCR, DNA sequencing was done. Data interpretation was done by using several softwares like BLAST alignment tool, Chromas Lite, Mega 5.2, Phyre 2, VMD 1.9.1, & PyMOL. A polymorphic change was detected in the protein coding region of Myc gene, which causes an amino acid substitution at lys355 by Arg, thus changing the Myc protein sequence. But this change might not affect protein structure much, as in some bHLH proteins Arg355 resides normally. Some changes in the 3'UTR were also detected which might play crucial part in stabilizing the Myc protein, by altering silencer box or miRNA binding sites. Thus high level of stable Myc protein causes increase cell division leading to tumor production.
This study will make available the genetic data and contribute substantial addition in the existing information in animal genetic resources. It would also aid in future to assess the possibility whether Myc can serve as a useful marker for diagnosis and prognosis of these malignancies. The need for today is to develop valid biomarkers, which can be incorporated in ongoing in vivo and in vitro clinical mechanistic and improve the diagnosis & prognosis of this dreadful disease.