Patterns of HIV viremia and viral suppression before diagnosis of non-AIDS-defining cancers in HIV-infected individuals

How Does Infection with Human Papillomavirus 16 and 18 Impact on DNA Damage and Repair in Cervical Cells and Peripheral Blood?

Human papillomavirus (HPV) infection is one of the most common sexually transmitted diseases worldwide and a prime cause of cervical cancer. The HPV DNA is detected in approximately 80-90% of all cervical cancers, with HPV 16 and 18 being the high risk conferring human carcinogens. DNA damage and diminished DNA repair mechanisms are potential biological surrogates of HPV infection that warrant further research in different tissues and populations. Notably, we do not know the extent to which the high risk HPV 16 and 18 differentially affect cervical cells versus other systems such as peripheral blood lymphocytes (PBLs). We evaluated DNA damage and repair in women who tested positive for HPV 16 or HPV 18 and healthy control women without HPV 16 or HPV 18 infection. We found that the DNA damage as measured by the Comet assay was markedly greater in cervical cells of women with HPV 16 (mean: 8.1 as% DNA in tail, 95% CI: 7.6-8.7) or HPV 18 infection (mean: 9.6, 95% CI: 8.9-10.2) than controls (mean: 6.7, 95% CI: 6.2-7.4) (p < 0.05). By contrast, in PBLs, we did not find a significant difference in DNA damage between women with HPV 16 or 18 infection versus controls, as measured by the Comet assay or the Conventional Chromosomal Aberration analysis (p > 0.05). We observed, however, the DNA repair capacity, as measured by the X-ray induced challenge (XRC) assay, was significantly impaired in PBLs from women with HPV 16 or 18 infection compared to controls (p < 0.05). This is the first comparative study, to the best of our knowledge, suggesting that the cervical swab cells might be better suited than peripheral lymphocytes as biosamples for detection of HPV 16 or 18 biological effects on DNA damage. In addition, these findings suggest that the Comet assay performed only in PBLs may potentially lead to false negative diagnosis of DNA damage. Taken together, these observations contribute to development of future diagnostic innovation and precision sampling strategies for robust detection of the biological effects of HPV 16 or 18 in women. We conclude by a brief discussion of implications for HPV clinical diagnostics and precision medicine innovation.

Virologic and Immunologic Outcomes in HIV-Infected Patients with Cancer

Achievement and maintenance of virologic suppression after cancer diagnosis have been associated with improved outcomes in HIV-infected patients, but few studies have analyzed the virologic and immunologic outcomes after a cancer diagnosis. All HIV-infected patients with a diagnosis of cancer between 2000 and 2011 in an urban clinic population in Baltimore, MD, were included for review. HIV-related outcomes (HIV-1 RNA viral load and CD4 cell count) were abstracted and compared for patients with non-AIDS-defining cancers (NADCs) and AIDS-defining cancers (ADCs). Four hundred twelve patients with baseline CD4 or HIV-1 RNA viral load data were analyzed. There were 122 (30%) diagnoses of ADCs and 290 (70%) NADCs. Patients with NADCs had a higher median age (54 years vs. 43 years, p < .0001) and a higher frequency of hepatitis C coinfection (52% vs. 36%, p = .002). The median baseline CD4 was lower for patients with ADCs (137 cells/mm³ vs. 314 cells/mm³) and patients with NADCs were more likely to be suppressed at cancer diagnosis (59% vs. 25%) (both p < .0001). The median CD4 for patients with NADCs was significantly higher than patients with ADCs at 6 and 12 months after diagnosis and higher at 18 and 24 months, but not significantly. Patients with an NADC had 2.19 times (95% CI 1.04-4.62) the adjusted odds of being suppressed at 12 months and 2.17 times the odds (95% CI 0.92-5.16) at 24 months compared to patients with an ADC diagnosis. For patients diagnosed with ADCs and NADCs in this urban clinic setting, both virologic suppression and immunologic recovery improved over time. Patients with NADCs had the highest odds of virologic suppression in the 2 years following cancer diagnosis.

Immediate Antiretroviral Therapy Reduces Risk of Infection-Related Cancer During Early HIV Infection

BACKGROUND

 In the Strategic Timing of Antiretroviral Treatment (START) study, immediate combination antiretroviral therapy (cART) initiation reduced cancer risk by 64%. We hypothesized that risk reduction was higher for infection-related cancer and determined by differences in CD4 cell counts and human immunodeficiency virus (HIV) RNA between the study arms.

METHODS

 Incident malignancies in START were categorized into infection-related and infection-unrelated cancer. We used Cox models to assess factors associated with both cancer categories. We used sequential adjustment for baseline covariates, cancer risk factors, and HIV-specific variables to investigate potential mediators of cancer risk reduction with immediate cART.

RESULTS

 There were 14 cancers among persons randomized to immediate cART (6 infection-related and 8 infection-unrelated) and 39 cancers in the deferred arm (23 infection-related and 16 infection-unrelated); hazard ratios of immediate vs deferred cART initiation were 0.26 (95% confidence interval [CI], .11-.64) for infection-related and 0.49 (95% CI, .21-1.15) for infection-unrelated cancer. Independent predictors of infection-related cancer were older age, higher body mass index, low- to middle-income region, HIV RNA, and baseline CD8 cell count. Older age and baseline CD8 cell count were independent predictors of infection-unrelated cancer. Adjustment for latest HIV RNA level had little impact on the protective effect of immediate cART on infection-related cancer. Adjustment for latest HIV RNA level, but not for CD4 cell count or cancer risk factors, attenuated the effect of immediate cART on infection-unrelated cancer.

CONCLUSIONS

 Immediate cART initiation significantly reduces risk of cancer. Although limited by small sample size, this benefit does not appear to be solely attributable to HIV RNA suppression and may be also mediated by other mechanisms.