Research Advances Understanding of Cancer Rates in HIV-Infected Patients

Overview of the Study

Recent research conducted by Case Western Reserve University in the United States has made significant progress in uncovering the reasons behind the elevated cancer rates among HIV-infected patients. While antiretroviral therapy has effectively reduced the risk of AIDS-related cancers, such as Kaposi’s sarcoma and certain B-cell lymphomas, cancer remains a predominant cause of mortality for individuals diagnosed with AIDS or chronic HIV infection.

Increased Cancer Risk with Age

As HIV-infected individuals age, the likelihood of developing non-AIDS-defining cancers rises. This trend is likely attributed to the extended lifespans enabled by antiretroviral treatments. Specifically, older HIV-infected patients exhibit heightened risks for various cancers, including lung, oral cavity/pharyngeal, anal, and liver cancers.

The Connection Between HIV and Cancer

Extracellular Vesicles as a Link

A report published in Nature Communications, led by researcher Ge Jin, proposes that extracellular vesicles (EVs) play a crucial role in linking HIV infection to cancer development. These EVs are small membrane-bound vesicles secreted by cells, containing molecular cargo that can be transferred to other cells throughout the body. Their significance in cancer research lies in their ability to communicate cancer-related signals across different cell types.

Effects of EVs on Cancer Cell Dynamics

Jin’s team discovered that EVs released by HIV-infected cells contribute to the growth of cancer cells. The research involved isolating EVs from HIV-infected immune cells and blood samples of HIV-positive patients. When these EVs were introduced to cancerous cells, researchers observed notable changes in behavior. Specifically, cancer cells treated with EVs from HIV-infected sources exhibited increased growth rates, motility, and tissue invasion compared to those treated with EVs from uninfected cells.

Identifying the Molecular Mechanisms

The study identified a specific RNA molecule within the HIV-related EVs, known as the HIV transactivating response (TAR) element RNA, which was linked to the upregulation of cancer-related genes and the activation of cancer signaling pathways.

Future Directions in Cancer Prevention Research

Need for Human Studies

This research marks a significant advancement in understanding the relationship between HIV and cancer risk. The study utilized both controlled laboratory samples and human subject data, enhancing the applicability of the findings to real-world HIV-infected populations. Nevertheless, further human studies are essential before these insights can inform the development of preventative treatments for clinical application.

Implications for Cancer Prevention

Understanding the mechanisms of cancer risk associated with HIV is critical for prevention efforts. The findings from this study offer valuable information for researchers and healthcare professionals regarding the interplay between HIV and cancer. They also highlight potential molecular targets for future preventative treatment strategies.

References

Chen, L., Feng, Z., Yue, H., Bazdar, D., Mbonye, U., Zender, C., Harding, C.V., Bruggeman, L., Karn, J., Sieg, S.F., Wang, B., & Jin, G. Exosomes derived from HIV-1-infected cells promote growth and progression of cancer via HIV TAR RNA. Nat. Comm. 9:4585 (2018).
Mahale, P., Engels, E. A., Coghill, A. E., Kahn, A. R. & Shiels, M. S. Cancer risk in older people living with human immunodeficiency virus infection in the United States. Clin. Infect. Dis. 67, 50–57 (2018).