HIV research paves way for new ovarian cancer therapies

HIV research has identified a new target for ovarian cancer by selectively blocking a cleft in the retinoblastoma protein that protects tumour-supporting macrophages.

The discovery could make ovarian – and potentially other – cancers more responsive to immunotherapies, treatments that use the body’s immune system to fight disease.

Scientists at the Wistar Institute found that targeting a specific cleft in the retinoblastoma protein removed only tumour-supporting macrophages while sparing those that fight disease.

Macrophages are immune cells that can either attack tumours or shield them from harm.

The work builds on decades of HIV studies led by Dr Luis Montaner, executive vice president of the Wistar Institute and director of its HIV Cure and Viral Diseases Center.

Montaner said: “This target emerged from our work understanding how macrophages survive HIV infection.

“It shows how insights from one field of medicine can inform breakthroughs in another.”

Targeting tumour-protecting macrophages without harming beneficial ones has long been a challenge.

Wistar researchers showed that selectively inhibiting this protein cleft depleted only tumour-supporting macrophages, leaving protective immune cells intact. Animal studies confirmed tumour shrinkage using this approach.

Montaner said: “This is a first-in-kind target against a solid tumour.

“It opens new avenues for therapies that could complement existing immunotherapies.”

The study highlights the value of long-term, cross-disciplinary research. It took more than 10 years from the initial HIV-linked finding to identifying this cancer target.

Next steps include exploring applications in acute myeloid leukaemia, pancreatic cancer and combination therapies.