Non-AIDS-defining cancers and HIV infection

Burden of non-AIDS-defining and non-virus-related cancers among HIV-infected patients in the combined antiretroviral therapy era

The risk of cancer is substantially increased in HIV-infected patients. However, little is known about non-AIDS-defining cancers (NADCs) without an infectious etiology. A total of 5,090 HIV-infected patients registered in the Local Health Authority (LHA) of Brescia and receiving primary care at our clinic were included in a retrospective (1999-2009) analysis. The cancer diagnoses were obtained through a record-linkage procedure between our database and the LHA general database and population-based Cancer Registry of LHA. We compared risks of these malignancies with those of the general population living in the same health area by using age-standardized incidence ratios (SIRs). Poisson regression analysis was used to assess factors associated with non-virus-related NADCs. We recorded an increase in the SIR of non-virus-related NADCs over time, with 138 cancers diagnosed in 131 patients. The mean incidence rate was 42.6/10,000 person years and the median age at the diagnosis was 49 (range, 28-78) years old. Stratifying for gender, only HIV-infected males had an increased risk of non-virus-related NADCs [SIR=1.86; 95% confidence interval (CI), 1.55-2.26]. Risk was higher for lung (SIR=3.59; 95% CI, 2.36-5.45) and testis cancer (SIR=3.11; 95% CI, 1.48-6.52). However,, cancers of the prostate and breast in HIV-positive men and women were null (SIR=1.10; 95% CI, 0.53-2.32 and SIR=0.91; 95% CI, 0.47-1.74, respectively). The only predictors of non-virus-related NADCs included older age [incidence rate ratio (IRR)=1.10; 95% CI, 1.08-1.12 per each additional year, p<0.001] and a shorter or no exposition to combined antiretroviral therapy (cART) (IRR=2.31; 95% CI, 1.38-3.89, p=0.002). A CD4⁺ count lower than 50/mm³ was significantly associated with cancers only in the univariate model (IRR=1.40; 95% CI, 0.99-1.98, p=0.057). HIV-infected men showed a 2-fold increased risk of non-virus-related NADCs compared to the general population. However, the use of cART appeared to be beneficial in protecting against the development of these malignancies.

Changing patterns of anal canal carcinoma in the United States

PURPOSE

Persistent human papillomavirus infection is associated with squamous cell carcinoma of the anal canal (SCCA). With changing sexual behaviors, SCCA incidence and patient demographics may also have changed in recent years.

METHODS

The Surveillance, Epidemiology, and End Results public-use data set from 1973 to 2009 was analyzed to determine incidence trends for and demographic factors characterizing SCCA. Joinpoint analyses identified time points when incidence rates changed. For comparison, similar analyses were conducted for anal adenocarcinoma.

RESULTS

Joinpoint analyses identified 1997 as the single inflection point among 11,231 patients with SCCA, at which the slope of incidence rates statistically increased (1997 to 2009 v 1973 to 1996: risk ratio [RR], 2.2; 95% CI, 2.1 to 2.3). Annual percent change (APC) increased for all SCCA stages and was the greatest for anal carcinoma in situ (CIS; APC, 14.2; 95% CI, 10.2 to 18.4). Demographic changes characterizing later versus earlier time period included younger age at diagnosis and rising incidence rates in all stage, sex, and racial groups. During 1997 to 2009, women were less likely to present with CIS (RR, 0.3; 95% CI, 0.3 to 0.3) but more likely to present with localized (RR, 1.2; 95% CI, 1.1 to 1.3) and regional SCCA (RR, 1.5; 95% CI, 1.4 to 1.7). In contrast, adenocarcinoma APCs among 1,791 patients remained stable during this time period.

CONCLUSION

CIS and SCCA incidence increased dramatically after 1997 for men and women, although men were more likely to be diagnosed with CIS. These changes likely resulted from available screening in men and argue for efforts to identify high-risk individuals who may benefit from screening.

Chromosomal radiosensitivity of HIV positive individuals

PURPOSE

Radiosensitivity in relation to the human immunodeficiency virus (HIV) status is important in South Africa as the prevalence of HIV infections is high. In this study the in vitro chromosomal radiosensitivity of HIV positive individuals was investigated and compared with that of HIV negative individuals.

MATERIALS AND METHODS

Blood samples from 59 HIV positive and 39 HIV negative individuals were exposed in vitro to doses of 6MV X-rays ranging from 1-4 Gy. Chromosomal radiosensitivity was assessed with the micronucleus assay. Micronuclei are a measure of chromosomal damage and were quantified in at least 500 binucleated lymphoblasts (BN) per sample. Un-irradiated control samples from each donor were also analysed.

RESULTS

In 47% of HIV positive individuals difficulties with cell stimulation by adding phytohaemagglutinin (PHA) to blood cultures were noticed which resulted in insufficient yield of BN for microscopic analysis. Micronuclei frequencies were consistently higher in irradiated lymphocytes obtained from HIV positive individuals compared to that observed in cells from HIV negative donors. Data for both groups were fitted to the linear-quadratic equation Y = alphaD + betaD(2) where Y is the number of micronuclei in 500 binucleated cells and D is the dose in Gy. The fitted parameters for respectively HIV positive and HIV negative lymphocytes are alpha = 80.17 Gy(-1), beta = 14 Gy(-2) and alpha = 54.5 Gy(-1), beta = 16.2 Gy(-2). The confidence ellipses of these parameters are separated indicating that the increase in radiosensitivity is statistically significant.

CONCLUSION

T-lymphocytes of HIV infected individuals were considerably more sensitive to X-rays compared to that of HIV negative donors. This may have implications for normal tissue tolerance during radiotherapy as well as for the radiological health of radiation workers.

Infectious complications of cancer chemotherapy in HIV patients

The outcome for HIV-infected patients with cancer has dramatically improved in the highly active antiretroviral therapy (HAART) era, probably due to improvements in immune status and bone marrow function that allow the possibility of increased drug-dose intensity with a higher complete remission rate. Although data regarding the optimal management of these cancers are lacking, current studies suggest that patients with HIV-associated malignancies could be treated using approaches similar to those for their counterparts in the general population (ie, with chemotherapy, radiation, and appropriate use of supportive measures). In the HAART era, the AIDS-related mortality rate has decreased by approximately 70%, and so the cause of the growing number of reports of cancers in HIV patients is unclear. Clearly, non-AIDS-defining malignancies account for more morbidity and mortality than AIDS-defining malignancies. Prevention strategies are needed to adequately deal with HIV-associated cancers in an aging and growing HIV-positive population.

Natural immunity to pluripotency antigen OCT4 in humans

OCT4 is a transcription factor critical for the pluripotency of human embryonal stem (ES) and induced pluipotency stem (IPS) cells. OCT4 is commonly expressed in germ-cell tumors as well as putative cancer stem cells in several tumors, and is a key determinant of oncogenic fate in germ-cell tumors. The capacity of the human immune system to recognize this critical stem-cell gene is not known, but has implications for preventing tumors with ES/IPS-based therapies and targeting stem-cell pathways in cancer. Here we show that OCT4-specific T cells can be readily detected in freshly isolated T cells from most (>80%) healthy donors. The reactivity to OCT4-derived peptides resides primarily in the CD45RO(+) memory T-cell compartment and consists predominantly of CD4(+) T cells. T cells reactive against OCT4-derived peptides can be readily expanded in culture using peptide-loaded dendritic cells. In contrast to healthy donors, immunity to OCT4 was detected in only 35% of patients with newly diagnosed germ-cell tumors. However, chemotherapy of germ-cell tumors led to the induction of anti-OCT4 immunity in vivo in patients lacking such responses at baseline. These data demonstrate the surprising lack of immune tolerance to this critical pluripotency antigen in humans. Harnessing natural immunity to this antigen may allow immune-based targeting of pluripotency-related pathways for prevention of cancers, including those in the setting of ES/IPS-based therapies.

Non-AIDS-defining deaths and immunodeficiency in the era of combination antiretroviral therapy

OBJECTIVE

To assess whether immunodeficiency is associated with the most frequent non-AIDS-defining causes of death in the era of combination antiretroviral therapy (cART).

DESIGN

Observational multicentre cohorts.

METHODS

Twenty-three cohorts of adults with estimated dates of human immunodeficiency virus (HIV) seroconversion were considered. Patients were seroconverters followed within the cART era. Measurements were latest CD4, nadir CD4 and time spent with CD4 cell count less than 350 cells/microl. Outcomes were specific causes of death using a standardized classification.

RESULTS

Among 9858 patients (71 230 person-years follow-up), 597 died, 333 (55.7%) from non-AIDS-defining causes. Non-AIDS-defining infection, liver disease, non-AIDS-defining malignancy and cardiovascular disease accounted for 53% of non-AIDS deaths. For each 100 cells/microl increment in the latest CD4 cell count, we found a 64% (95% confidence interval 58-69%) reduction in risk of death from AIDS-defining causes and significant reductions in death from non-AIDS infections (32, 18-44%), end-stage liver disease (33, 18-46%) and non-AIDS malignancies (34, 21-45%). Non-AIDS-defining causes of death were also associated with nadir CD4 while being cART-naive or duration of exposure to immunosuppression. No relationship between risk of death from cardiovascular disease and CD4 cell count was found though there was a raised risk associated with elevated HIV RNA.

CONCLUSION

In the cART era, the most frequent non-AIDS-defining causes of death are associated with immunodeficiency, only cardiovascular disease was associated with high viral replication. Avoiding profound and mild immunodeficiency, through earlier initiation of cART, may impact on morbidity and mortality of HIV-infected patients.

Malignant lymphomas (ML) and HIV infection in Tanzania

Background

HIV infection is reported to be associated with some malignant lymphomas (ML) so called AIDS-related lymphomas (ARL), with an aggressive behavior and poor prognosis. The ML frequency, pathogenicity, clinical patterns and possible association with AIDS in Tanzania, are not well documented impeding the development of preventive and therapeutic strategies.

Methods

Sections of 176 archival formalin-fixed paraffin-embedded biopsies of ML patients at Muhimbili National Hospital (MNH)/Muhimbili University of Health and Allied Sciences (MUHAS), Tanzania from 1996–2001 were stained for hematoxylin and eosin and selected (70) cases for expression of pan-leucocytic (CD45), B-cell (CD20), T-cell (CD3), Hodgkin/RS cell (CD30), histiocyte (CD68) and proliferation (Ki-67) antigen markers. Corresponding clinical records were also evaluated. Available sera from 38 ML patients were screened (ELISA) for HIV antibodies.

Results

The proportion of ML out of all diagnosed tumors at MNH during the 6 year period was 4.2% (176/4200) comprising 77.84% non-Hodgkin (NHL) including 19.32% Burkitt's (BL) and 22.16% Hodgkin's disease (HD). The ML tumors frequency increased from 0.42% (1997) to 0.70% (2001) and 23.7% of tested sera from these patients were HIV positive. The mean age for all ML was 30, age-range 3–91 and peak age was 1–20 years. The male:female ratio was 1.8:1. Supra-diaphragmatic presentation was commonest and histological sub-types were mostly aggressive B-cell lymphomas however, no clear cases of primary effusion lymphoma (PEL) and primary central nervous system lymphoma (PCNSL) were diagnosed.

Conclusion

Malignant lymphomas apparently, increased significantly among diagnosed tumors at MNH between 1996 and 2001, predominantly among the young, HIV infected and AIDS patients. The frequent aggressive clinical and histological presentation as well as the dominant B-immunophenotype and the HIV serology indicate a pathogenic association with AIDS. Therefore, routine HIV screening of all malignant lymphoma patients at MNH is necessary to enable comprehensive ARL diagnosis and formulation of preventive and therapeutic protocols.

Dose-reduced busulfan, cyclophosphamide, and autologous stem cell transplantation for human immunodeficiency virus-associated lymphoma: AIDS Malignancy Consortium study 020

Intensive chemotherapy for human immunodeficiency virus (HIV)-associated non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (HL) has resulted in durable remissions in a substantial proportion of patients. High-dose chemotherapy and autologous stem cell transplantation (AuSCT), moreover, has resulted in sustained complete remissions in selected patients with recurrent chemosensitive disease. Based on a favorable experience with dose-reduced high-dose busulfan, cyclophosphamide, and AuSCT for older patients with non-HIV-associated aggressive lymphomas, an AIDS Malignancy Consortium multicenter trial was undertaken using the same dose-reduced busulfan and cyclophosphamide preparative regimen with AuSCT for recurrent HIV-associated NHL and HL. Of the 27 patients in the study, 20 received an AuSCT. The median time to achievement of an absolute neutrophil count (ANC) of >or= 0.5 x 10(9)/L was 11 days (range, 9-16 days). The median time to achievement of an unsupported platelet count of >or= 20 x 10(9)/L was 13 days (range, 6-57 days). One patient died on day +33 posttransplantation from hepatic veno-occlusive disease (VOD) and multiorgan failure. No other fatal regimen-related toxicity occurred. Ten of 19 patients (53%) were in complete remission at the time of their day +100 post-AuSCT evaluation. Of the 20 patients, 10 were alive and event-free at a median of 23 weeks post-AuSCT. Median overall survival (OS) was not reached by 13 of the 20 patients alive at the time of last follow-up. This multi-institutional trial demonstrates that a regimen of dose-reduced high-dose busulfan, cyclophosphamide, and AuSCT is well tolerated and is associated with favorable disease-free survival (DFS) and OS probabilities for selected patients with HIV-associated NHL and HL.

Interventions for treating AIDS-associated Hodgkin s lymphoma in treatment-naive adults

BACKGROUND

Hodgkin's disease (HD) is the most common non-AIDS-defining malignancy in HIV-infected patients. Its unusually aggressive tumour behaviour includes a higher frequency of unfavourable histologic subtypes, high-stage and extranodal involvement by the time of presentation (anal canal, stomach), and poor therapeutic outcome, in comparison with HD outside the HIV setting. The optimal therapeutic strategy is still controversial, and median overall survival is short, ranging from 12 to 18 months. Thus, there is a need to identify the efficacy and safety of different interventions for AIDS-associated HD on overall survival and disease-free survival in treatment-naive adults with AIDS.

OBJECTIVES

To assess the effects of different interventions for treating AIDS-associated Hodgkin's disease including chemotherapy, bone marrow transplantation (BMT), and gene therapy on overall survival and disease-free survival in treatment-naive adults with AIDS.

SEARCH STRATEGY

We searched The Cochrane HIV/AIDS Group Trials Register (September 2006), which comprises references identified from comprehensive electronic database searches and handsearching of relevant journals and abstract books of conference proceedings. We also searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (Issue 3, 2006), MEDLINE (1966 to September 2006), EMBASE (1974 to September 2006) LILACS (1982 to September 2006), ISI Web of Knowledge (1993 to September 2006), and AIDSearch (1980 to December 2006). Date of most recent search: December 2006.

SELECTION CRITERIA

We searched for published or unpublished randomised controlled trials.

DATA COLLECTION AND ANALYSIS

We intended to summarise data by standard Cochrane Collaboration methodologies, but no eligible randomised controlled trials were identified.

MAIN RESULTS

We were unable to find any randomised controlled trials of interventions for treating AIDS-associated HD in treatment-naive adults with AIDS.

AUTHORS' CONCLUSIONS

Randomised controlled trials are needed to establish the efficacy and safety of interventions for treating AIDS-associated HD in treatment-naive adults with AIDS.

The growing problem of non-AIDS-defining malignancies in HIV

PURPOSE OF REVIEW

The incidence and spectrum of non-AIDS-defining cancers has continued to grow. As HIV-infected individuals live longer due to highly active antiretroviral therapy, their risk of dying from one of these cancers is increased. The recent literature pertaining to non-AIDS-defining cancers is reviewed.

RECENT FINDINGS

Recent epidemiological studies have identified higher rates of carcinoma of the anus, lung, breast, skin, conjunctiva, liver and prostate; hematopoietic malignancies such as Hodgkin's lymphoma, plasma-cell neoplasia and leukemia; and other neoplasms like melanoma and leiomyosarcoma in HIV-positive patients. The role of HIV-induced immunosuppression in the development of these non-AIDS-defining cancers appears less important than lifestyle habits like smoking and sun exposure, as well as coinfection with human papilloma, hepatitis B, hepatitis C and Epstein-Barr viruses.

SUMMARY

It is unclear whether the growing number of reports on non-AIDS-defining cancers reflects a true increased incidence or merely the product of increased surveillance, detection and reporting. Highly active antiretroviral therapy not only promotes longevity in the HIV-positive population, but may increase their risk of developing cancer like Hodgkin's lymphoma. Assertive prevention strategies are needed to adequately deal with non-AIDS-defining cancers in an aging and growing HIV-positive population.

HIV-1 Vpr induces ATM-dependent cellular signal with enhanced homologous recombination

An ATM-dependent cellular signal, a DNA-damage response, has been shown to be involved during infection of human immunodeficiency virus type-1 (HIV-1), and a high incidence of malignant tumor development has been observed in HIV-1-positive patients. Vpr, an accessory gene product of HIV-1, delays the progression of the cell cycle at the G2/M phase, and ATR-Chk1-Wee-1, another DNA-damage signal, is a proposed cellular pathway responsible for the Vpr-induced cell cycle arrest. In this study, we present evidence that Vpr also activates ATM, and induces expression of gamma-H2AX and phosphorylation of Chk2. Strikingly, Vpr was found to stimulate the focus formation of Rad51 and BRCA1, which are involved in repair of DNA double-strand breaks (DSBs) by homologous recombination (HR), and biochemical analysis revealed that Vpr dissociates the interaction of p53 and Rad51 in the chromatin fraction, as observed under irradiation-induced DSBs. Vpr was consistently found to increase the rate of HR in the locus of I-SceI, a rare cutting-enzyme site that had been introduced into the genome. An increase of the HR rate enhanced by Vpr was attenuated by an ATM inhibitor, KU55933, suggesting that Vpr-induced DSBs activate ATM-dependent cellular signal that enhances the intracellular recombination potential. In context with a recent report that KU55933 attenuated the integration of HIV-1 into host genomes, we discuss the possible role of Vpr-induced DSBs in viral integration and also in HIV-1 associated malignancy.