Oncogenomics.

The rapid developments in the field of genomics and proteomics are expected to lead to a further increase in the potential for early diagnosis, the fine-tuning of prognostic features of specific tumors and the detection of cancer predisposition. Oncogenomics has identified new drug targets for genotype-specific treatments and provided strategies to validate these targets and to develop drugs. With the potential need to stratify patients by genotype, clinical testing of targeted drugs has become more complicated while expectations of patients, investors, and funding agencies have become accelerated. Oncogenomics has progressed logically from molecular profiling to model systems, cancer pharmacology and clinical trials. Oncogenomics covers cutting-edge issues such as array-based diagnostics, pharmacogenomics, pharmacoproteomics and molecularly targeted therapeutics includes discussions of ethical, legal, and social issues related to cancer genomics and clinical trials.

Enzymatic studies of cisplatin induced oxidative stress in hepatic tissue of rats.

Cisplatin is an active cytotoxic agent that has proved to be successful in the treatment of various types of solid tumors. The drug-induced nephrotoxicity has been very well documented in clinical oncology. However, hepatotoxicity has been rarely characterized and paid attention to, and is the least studied. We have used rat as the model to evaluate the effect of cisplatin on liver antioxidant enzymes and to determine whether these modulations in enzymatic activities are involved in hepatotoxicity. Reports obtained from our study indicate that cisplatin increases lipid peroxidation in the treated tissue of rat. The drug is also involved in altering the thiol status of the tissue with concomitant alterations in the enzymatic antioxidants. Glutathione and glutathione reductase levels were significantly decreased after cisplatin therapy, whereas glutathione peroxidase, gamma-glutamyl transpeptidase and catalase showed a significant increase. No statistically significant change was observed in glutathione-S-transferase activity. After cisplatin treatment, cytochrome P 450 showed a significant increase, whereas cytochrome b5 was decreased. Thus, an alteration in enzymatic antioxidant status with increase in lipid peroxidation indicates that the enzymes play an important role in combating free radical induced oxidative stress on the tissue.