Identification of novel heterozygous Apex 1 gene variant (Glu87Gln) in patients with head and neck cancer of Indian origin

Determination of the effects of fusaric acid, a mycotoxin, on cytotoxicity, gamma-H2AX, 8-hydroxy-2 deoxyguanosine and DNA repair gene expressions in pancreatic cancer cells

Pancreatic cancer has a poor prognosis and is an important public health problem for developing countries. Oxidative stress plays an important role in cancer initiation, progression, proliferation, invasion, angiogenesis and metastasis. For this reason, one of the important strategic targets of new cancer therapeutics is to drive cancer cells into apoptosis through oxidative stress. In nuclear and mitochondrial DNA, 8-hydroxy-2'-deoxyguanosine and gamma-H2AX (γ-H2AX) are used as important oxidative stress biomarkers. Fusaric acid (FA) is a mycotoxin that mediates toxicity produced by Fusarium species and exhibits anticancer effects in various cancers via inducing apoptosis, cell cycle arrest, or other cellular mechanisms. The aim of this study was to determine the effects of fusaric acid on cytotoxic and oxidative damage in MIA PaCa-2 and PANC-1 cell lines. In this context, dose and time dependent cytotoxic effect of fusaric acid was determined by XTT method, mRNA expression levels of genes related to DNA repair were determined by RT-PCR, and its effect on 8-hydroxy-2'-deoxyguanosine and γ-H2AX levels was revealed by ELISA assay. According to XTT results, fusaric acid inhibits cell proliferation in MIA PaCa-2 and Panc-1 cells in a dose- and time-dependent manner. IC50 doses were determined as 187.74 μM at 48 h in MIA PaCa-2 cells and 134.83 μM at 48 h in PANC-1 cells, respectively. γ-H2AX and 8-OHdG changes were not found significant in pancreatic cancer cells. The mRNA expression levels of DNA repair-related genes NEIL1, OGG1, XRCC and Apex-1 change with exposure to fusaric acid. This study contributes to the therapeutic approaches to be developed for pancreatic cancer and demonstrates the potential of fusaric acid as an anticancer agent.

R248W Mutations in p53 Gene are Rare Among Indian Patients with Head-and-Neck Cancer

Cancer is one of the curses to humankind, decades of research in eradicating the disease from the society is proven difficult. Close interaction between clinicians and scientists helps us to translate clinical observations into molecular mechanism of the disease. The Cancer Genome Atlas data suggest that genetic alterations in p53 gene play a crucial role in head-and-neck squamous cell carcinoma (HNSCC) tumorigenesis. Understanding p53 aberrations and their impact on other cellular activities can help with the design of new, more effective therapeutic strategy that target p53 mutation-bearing HNSCC, thereby producing a personalized medicine approach for the disease.

In an effort to identify the role of R248W mutation of p53 gene in HNSCC patients of Indian origin, tumor samples were collected from 55 patients (n = 55), and polymerase chain reaction–restriction fragment length polymorphism technique was used to screen for the mutation using genomic DNA isolated from the tumors.

The results reveal that except for one patient (heterozygous), all the patients were negative for the mutation.

These results suggest that p53 R248W mutations are less prevalent in HNSCC Indian patients.

Prevalence of K-ras Codon 12 Mutations in Indian Patients with Head and Neck Cancer

In human tumors, somatic mutation frequently occur in K-ras gene at codon 12, which makes the K-ras protein hyper active leading to uncontrolled signaling for cell division: one of the important hall mark of cancer. In order to correlate mutations in K-ras to cause, response to treatment, disease progression and recurrence of Head and Neck Squamous Cell Carcinoma (HNSCC) the following study was undertaken. By using PCR-RFLP method prevalence of codon 12 in K-ras gene was studied in 56 HNSCC patients. High frequency of K-ras mutation was detected in codon 12 (60.71%). The result of this study helps us in understanding the role of K-ras somatic mutations in HNSCC patients and in designing novel treatment protocols for HNSCC patients.