New Delhi, Nov 18 (India Science Wire): Oropharyngeal cancer or tonsil cancer
as it is known in common parlance is increasingly becoming a matter of grave
concern. In 2018, a total of 92,887 new cases and 51,005 deaths due to the
disease were reported across the world. India has the highest incidence as well
as the mortality rate for this cancer type, with 17,903 new cases and 14,953
deaths reported for 2018.
Several etiological factors are associated with the development of the cancer
including consumption of tobacco (smoking and smokeless), areca nut, alcohol
and Human Papilloma Virus (HPV).
In India specifically, the higher incidence rates of the cancer have been
correlated to specific dietary and lifestyle habits such as chewing of areca or
betel nut, and consumption and exposure to smokeless tobacco. Studies have
also found it to be more prevalent among lower income groups. In particular,
there is a high incidence of this cancer type in the northeastern states of India
like Meghalaya, where the consumption of arecanut and tobacco is very high.
DNA Methylation is one of the ways in which genetic modifications happen,
which leads to a change in the expression of genes. It occurs early and
commonly in cancer. Further, there is a stable change of DNA, which can be
monitored in a lab. It is easy to detect even in small amounts and is known to
have potential in predicting survival differences and/or responses to therapy.
The identification and characterization of differentially methylated genes and
regions are used for the early detection of cancers leading to more effective
diagnosis and better treatment outcomes.
A study on the whole genome methylation profile for tonsil cancer was
recently undertaken on a subset of the northeast India population. There is a
need to expand the scope for such studies.
A team of scientists from the Department of Biotechnology’s National Institute
of Biomedical Genomics (DBT-NIBMG), Kalyani, North-eastern Hill University
(NEHU) and North Eastern Indira Gandhi Regional Institute of Health and
Medical Sciences (NEIGRIHMS), Shillong have sought to fill the gap, though
partially. They have jointly investigated the changes in the DNa methylation
and expression of genes in tumours of patients suffering from Oropharyngeal
cancer in Meghalaya. They, among other things, have found that as many as
241 genes were overexpressed and 194 were muted due to changes in the
DNA methylation in the tumor tissue of these patients.
The findings of the study are expected to significantly improve upon the
understanding of the disease and thus help in the development of better
drugs, diagnostic methods. The study was conducted under a research grant
funded by the Department of Biotechnology.
Speaking to India Science Wire, Dr.ArindamMaitra of NIBMG, a leader of the
study team along with Dr.SrimoyeeGhosh of NEHU, said, “this was the first
comprehensive study on genome whole genome DNA methylation and gene
expression of this cancer type from this region, albeit on a limited number of
patients. We plan to expand the study to a larger number of patients in other
states of the north east region. We have identified key changes in the
epigenome in these tumours which are predicted to have major roles in the
development of this cancer. We would like to use this information for the
development of biomarkers of oropharyngeal cancer which can be
implemented in the clinic for improved diagnosis and management of
patients”.
Besides Dr Maitra and Dr.Ghosh, the team consisted ofDr.Neizekhotuo Brian
Shunyu from NEIGRIMS and Lastborn Marathon, SahanaGhosh,
ArindamPalodhi, and Mohamed Imran. They have published a report of their
work in Frontiers of Genetics. (India Science Wire)