Hudson Institute researchers have shown for the first time that a diabetes drug called sitagliptin can limit tumour growth, and possibly extend survival rates from epithelial ovarian cancer, the most common and dangerous type of ovarian cancer.
Key points
- Type 2 diabetes drug sitagliptin has been shown to help the immune response to ovarian cancer
- The drug intercepts a rogue enzyme, DPP4, that stops cancer-fighting T-cells from doing their job
- The pre-clinical study suggests sitagliptin may be suitable as an additional therapy for patients between chemotherapy cycles and to improve overall survival.
In this study, published in Cancers, researchers looked at how sitagliptin, an FDA-approved drug that is often used to treat Type 2 diabetes, can improve the immune response by blocking the enzyme DPP4 which stops cancer-fighting T-cells from infiltrating tumours.
Current treatments for ovarian cancer involve highly invasive surgery and chemotherapy. However, recurrence of the disease and acquired resistance to chemotherapy is common, accounting for the disproportionally high mortality rate among epithelial ovarian cancer patients.
What did the ovarian cancer study show?
Hudson Institute researcher Dr Amy Wilson, the first author on the study said, "Several aspects of the immune system act as an SOS signal when an ovarian tumour is growing. The immune system responds to this SOS call by sending in cells such as T-cells to help eliminate the growing tumour."
However, ovarian cancer tumours are cunning, and can 'cut the cord' between the tumour and the immune system using the enzyme DPP4. They do this by switching off the SOS signal and allowing the tumour to hide from the immune system and continue to grow.
Preclinical trials have shown that sitagliptin helps restore communication within the immune system by blocking DPP4, and reducing the number of immuno-suppressive molecules circulating in the body.
"Our data suggests that sitagliptin may be suitable as an additional therapy for patients between chemotherapy cycles as a new approach to enhance immunity, optimise T-cell activation and improve overall survival," said Dr Wilson.
Hudson Institute Director and CEO Professor Elizabeth Hartland said: "Treatments for ovarian cancer haven't changed much in 30 years. Women are desperate for new approaches that can improve survival rates. Our ovarian cancer researchers are dedicated to better health outcomes for these patients."
How does this study move ovarian cancer research forward?
Immunotherapy – the treatment of disease by activating or helping the immune system – is a relatively new form of treatment that shows great potential. "This study shows that sitagliptin may help the immune system do its job, when all other treatments have failed," Dr Wilson said.
Epithelial ovarian cancer facts
- There is no available screening test for any type of ovarian cancer
- About 1500 women are diagnosed each year in Australia with all types of ovarian cancer and about 1000 die from the disease
- Epithelial ovarian cancer is the most common and dangerous type of ovarian cancer
- Epithelial ovarian cancer has a 43 per cent five-year survival rate
- 70 per cent of women with epithelial ovarian cancer will relapse within three years of initial treatment.
Collaborators | RMIT
Funders | NHMRC, Victorian Government's Operational Infrastructure Support Program
