New research shows HIV promotes cancer growth
People living with HIV are at a greater risk of dying from certain cancers because their infected immune systems promote the aggressive growth of tumors, according to new research.
The discovery puts the spotlight on an underrepresented population in cancer research. While HIV-positive patients are living longer with the help of anti-retroviral therapies, they are at risk for many of the same diseases that come with aging.
The latest findings, published in the journal Nature Communications last month, identify that HIV-infected T-cells, the main fighters in the immune system, produce and give off microscopic particles that promote cancer growth while they travel around the body.
“This is the first publication in the field to specifically address the question” why HIV-positive patients develop specific types of cancer and when, said Ge Jin, lead author of the study and an associate professor in the Department of Biological Sciences at Case Western Reserve University School of Dental Medicine.
Age is a known risk factor for developing cancers, with half of diagnoses occurring in people 65 years old and older. By 2030, more than 20 percent of the population of people living with HIV will be 65 and older.
While there are an about 1.1 million people living with HIV in the U.S., an estimated 40,000 new diagnoses occur each year.
Before the development of anti-retroviral therapies and as HIV developed into AIDS, people were 500 times more likely to be diagnosed with blood cancers like Kaposi sarcoma and 12 times more likely to develop non-Hodgkin’s lymphoma.
Those numbers are steadily declining with use of anti-retrovirals, according to the National Cancer Institute, but HIV-positive patients are at an elevated risk for anal, lung, liver, head and neck cancer and Hodgkin’s lymphoma.
The cancer institute says the elevated risk arises from a combination of factors including higher rates of hepatitis B and C, human papillomavirus and a patient’s suppressed immune system, but the latest research highlights HIV itself as a contributing factor.
Jesse Milan Jr., CEO of AIDS United, a nonprofit policy and advocacy group, said the new research shifts understanding on how people living with HIV develop new diseases.
“We see higher rates of multiple types of cancer, heart disease and even dementia. Till now, these effects have mostly been attributed to inflammation associated with any viral infection, in addition HIV’s impact on the immune system,” Mr. Milan said in an email to The Washington Times.
“But this latest research suggests that the virus itself supports the development of some cancers As people live longer with HIV, thanks to ever-improving treatments, the population living with the disease will trend significantly older,” Mr. Milan wrote. “It’s imperative that we start to prepare for what that will mean for our health care delivery systems.”
Mr. Ge said he was prompted to do the research because of the conflicting science about people with HIV living longer but developing certain cancers at higher rates, earlier in their lives and more aggressively.
“Even if HIV is under control by [anti-retroviral therapy], people just simply don’t understand why they have higher incidence rate of those cancers compared to general population,” he said.
In the study, Mr. Ge and colleagues found that the HIV-infected T-cells traveling around the body produce and give off “small, teeny-tiny, nano-particles” called exosomes that “promote cancer cell proliferation and invasion.”
“This inspired us to think about, maybe this is the reason HIV-positive patients, they have higher instance in those specific cancers,” he said.
The scientists went further, finding that HIV-infected T-cells have a receptor that matches with that of cancer cells of specific diseases like lung cancer and causes cancer cells to grow, stimulate movement and invade other parts of the body.
Mr. Ge said this discovery can spark thinking about new treatments.
“If you have something that stimulates their cancer growth, if we have a drug that eliminates it or blocks it, then the RNA can’t do it’s job, that will delete the cancer progression,” he said.