Pune research group gives new hope for targeted therapy to ovarian cancer patients

PUNE: Research at the National Centre for Cell Sciences (NCCS) here, has succeeded in showing the direction for personalised, targeted therapy for patients suffering

PUNE: Research at the National Centre for Cell Sciences (NCCS) here, has succeeded in showing the direction for personalised, targeted therapy for patients suffering from High Grade Serous Carcinoma (HGSC), the most dominant form of epithelial ovarian cancer known for its aggressiveness and high mortality rate.

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Led by award-winning scientist Sharmila Bapat, the team of researchers has identified three patient sub-types within HGSC paving the way for new drug targets and better therapy outcomes. A report on this clinical stratification of HGSC tumour using a panel of six biomarkers was published in the Journal of Clinical Medicine, an international peer-reviewed journal published by the Switzerland-based MDPI (Multidisciplinary Digital Publishing Institute), earlier this year.

The NCCS ovarian cancer research group, the first-of-its-kind to be initiated in India in 2001, worked with onco-pathologists from four other centres which included Tata Medical Centre, Kolkata, KEM Hospital, Pune, Armed Forces Medical College (AFMC), Pune and Inlaks and Budhrani Hospital, Pune, to validate the findings of this study.

“Earlier, the gold standard for cancer diagnosis was pathology, where biopsy would reveal malignant cells and after surgery, a histopathological section would reveal the tumour sub-type. In the last two decades, cancer research has moved towards molecular characterisation. Sometimes, tumours that show the same sub-type in histopathological section might be different at a molecular level. We started looking for molecular markers then and the TCGA came in handy,” explained Bapat.

TCGA is ‘The Cancer Genome Atlas’, an open source of molecular profiles of several tumour types started in 2006 in the US.

“TCGA became an important source of data for us. Through computational analysis, we were able to identify three patient subtypes within HGSC. It was then validated at the cell line level (mouse models) which can be studied for different parameters. Then, a student of mine, Dr. Swapnil Kamble, actually looked at samples of Indian patients. We collaborated with the above centres and our findings were validated by experts at the clinical level,” Bapat said.

Bapat, who is known for her earlier work on ovarian cancer stem cells, said that this latest study, which began in 2014, accounts for the heterogeneity of ovarian cancer and raises important questions about our readiness to treat sub-types that are not targeted by PARP1 inhibitors, the standard treatment available for ovarian cancer in clinics.

“While our study has established the class stratification within HGSC, another finding it has thrown up is that certain tumours also switch classes after therapy. Do we have the class-specific therapies required to treat them? Further research should move in this direction,” she said.

HGSC: Most dominant form of ovarian cancer

•High Grade Serous Carcinoma (HGSC) is a type of tumour found in the epithelial layer of the ovary and is the most dominant form of ovarian cancer. Though the incidence of the disease is low, the mortality rate is very high.

•HGCS is called as the silent killer because the symptoms are general (like bloating, fatigue) and non-specific and may not be taken seriously.

•While cervical cancer and breast cancer can be picked up early due to surveillance, early diagnosis of ovarian cancer remains a challenge.

•No specific screening tests and no targeted therapy (other than PARP1 inhibitors) have led to poor therapy outcomes for ovarian cancer.