HIV-Associated Lung Cancer

Implementation of a lung cancer screening initiative in HIV-infected subjects

In this pilot program of low-dose computed tomography (LDCT) for the screening of lung cancer (LC) in a targeted population of people with HIV (PWH), its prevalence was 3.6%; the number needed to screen in order to detect one case of lung cancer was 28, clearly outweighing the risks associated with lung cancer screening. While data from additional cohorts with longitudinal measurements are needed, PWH are a target population for lung cancer screening with LDCT.

Cancer Etiology and Prevention Principle: "1 + X"

Cancer was previously thought to be an inevitable aspect of human health with no effective treatments. However, the results of in-depth cancer research suggest that most types of cancer may be preventable. Therefore, a comprehensive understanding of the disparities in cancer burden caused by different risk factors is essential to inform and improve cancer prevention and control. Here, we propose the cancer etiology and prevention principle "1 + X," where 1 denotes the primary risk factor for a cancer and X represents the secondary contributing risk factors for the cancer. We elaborate upon the "1 + X" principle with respect to risk factors for several different cancer types. The "1 + X" principle can be used for precise prevention of cancer by eliminating the main cause of a cancer and minimizing the contributing factors at the same time.

Responses of Mast Cells to Pathogens: Beneficial and Detrimental Roles

Mast cells (MCs) are strategically located in tissues close to the external environment, being one of the first immune cells to interact with invading pathogens. They are long living effector cells equipped with different receptors that allow microbial recognition. Once activated, MCs release numerous biologically active mediators in the site of pathogen contact, which induce vascular endothelium modification, inflammation development and extracellular matrix remodeling. Efficient and direct antimicrobial mechanisms of MCs involve phagocytosis with oxidative and non-oxidative microbial destruction, extracellular trap formation, and the release of antimicrobial substances. MCs also contribute to host defense through the attraction and activation of phagocytic and inflammatory cells, shaping the innate and adaptive immune responses. However, as part of their response to pathogens and under an impaired, sustained, or systemic activation, MCs may contribute to tissue damage. This review will focus on the current knowledge about direct and indirect contribution of MCs to pathogen clearance. Antimicrobial mechanisms of MCs are addressed with special attention to signaling pathways involved and molecular weapons implicated. The role of MCs in a dysregulated host response that can increase morbidity and mortality is also reviewed and discussed, highlighting the complexity of MCs biology in the context of host-pathogen interactions.

[Advances in Diagnosis and Management of Subcentimeter Pulmonary Nodules]

With the widespread use of high-resolution multislice spiral computed tomography and the popularization of regular physical examinations, the prevalence of clinically diagnosed subcentimeter pulmonary nodules is increasing. Subcentimeter pulmonary nodules have low malignant probability, however, the diagnosis and management are of high difficulty and it is likely to misdiagnose and miss malignant nodules. Therefore, the evaluation and management of subcentimeter pulmonary nodules have always been the key points of clinical work. This article reviews and summarizes the progress in the evaluation and management of subcentimeter pulmonary nodules.

Efavirenz and Lopinavir/Ritonavir Alter Cell Cycle Regulation in Lung Cancer

Highly active anti-retroviral treatment (HAART) is currently the most effective treatment for HIV/AIDS. Additionally, HIV positive patients receiving HAART have a better health-related quality of life (HRQoL). Cancers previously associated with HIV/AIDS also known as the AIDS defining cancers (ADCs), such as Kaposi's sarcoma and non-Hodgkin's lymphoma have been on the decline since the introduction of HAART. However, non-AIDS defining cancers (NADCs), in particular, lung cancers have been documented to be on the rise. The association between the use of HAART components and lung carcinogenesis is poorly understood. This study aimed at elucidating the effects of two HAART components [efavirenz (EFV), and lopinavir/ritonavir (LPV/r)] on lung cancer. This was achieved through the use of in vitro cell biological approaches to assess cell health, including cell viability, Real Time Cell Analysis (RTCA) growth monitoring, evaluation of the cell cycle, and progression to apoptosis, following on drug treatments. At plasma level concentrations, both EFV and LPV/r induced S-phase arrest, while at lower concentrations both drugs promoted the progression of cells into G2/M phase following cell cycle FACS analysis. At higher concentrations although cell viability assays reflected anti-proliferative effects of the drugs, this was not statistically significant. RTCA showed a significant decline in cell viability in response to the highest dose of LPV/r. Dual staining by Annexin V-FITC and PI confirmed significant pro-apoptotic effects were promoted by LPV/r. Both EFV and LPV/r exert double-edged oncogenic effects on MRC-5 and A549 lung cells, acting to either promote cell proliferation or to enhance apoptosis. This is affected by EFV and LPV/r altering cell cycle progression, with a significant S-phase arrest, this being an indication of cellular stress, cytotoxicity, and DNA damage within the cell.

HIV gp120 Induces the Release of Proinflammatory, Angiogenic, and Lymphangiogenic Factors from Human Lung Mast Cells

Human lung mast cells (HLMCs) express the high-affinity receptor FcεRI for IgE and are involved in chronic pulmonary diseases occurring at high frequency among HIV-infected individuals. Immunoglobulin superantigens bind to the variable regions of either the heavy or light chain of immunoglobulins (Igs). Glycoprotein 120 (gp120) of HIV-1 is a typical immunoglobulin superantigen interacting with the heavy chain, variable 3 (V_H3) region of human Igs. The present study investigated whether immunoglobulin superantigen gp120 caused the release of different classes of proinflammatory and immunoregulatory mediators from HLMCs. The results show that gp120 from different clades induced the rapid (30 min) release of preformed mediators (histamine and tryptase) from HLMCs. gp120 also caused the de novo synthesis of cysteinyl leukotriene C₄ (LTC₄) and prostaglandin D₂ (PGD₂) from HLMCs. Incubation (6 h) of HLMC with gp120 induced the release of angiogenic (VEGF-A) and lymphangiogenic (VEGF-C) factors from HLMCs. The activating property of gp120 was mediated through the interaction with IgE V_H3⁺ bound to FcεRI. Our data indicate that HIV gp120 is a viral superantigen, which induces the release of different proinflammatory, angiogenic, and lymphangiogenic factors from HLMCs. These observations could contribute to understanding, at least in part, the pathophysiology of chronic pulmonary diseases in HIV-infected individuals.

Lung Cancer (LC) in HIV Positive Patients: Pathogenic Features and Implications for Treatment

: The human immunodeficiency virus (HIV) infection continues to be a social and public health problem. Thanks to more and more effective antiretroviral therapy (ART), nowadays HIV-positive patients live longer, thus increasing their probability to acquire other diseases, malignancies primarily. Senescence along with immune-system impairment, HIV-related habits and other oncogenic virus co-infections increase the cancer risk of people living with HIV (PLWH); in the next future non-AIDS-defining cancers will prevail, lung cancer (LC) in particular. Tumor in PLWH might own peculiar predictive and/or prognostic features, and antineoplastic agents' activity might be subverted by drug-drug interactions (DDIs) due to concurrent ART. Moreover, PLWH immune properties and comorbidities might influence both the response and tolerability of oncologic treatments. The therapeutic algorithm of LC, rapidly and continuously changed in the last years, should be fitted in the context of a special patient population like PLWH. This is quite challenging, also because HIV-positive patients have been often excluded from participation to clinical trials, so that levels of evidence about systemic treatments are lower than evidence in HIV-uninfected individuals. With this review, we depicted the epidemiology, pathogenesis, clinical-pathological characteristics and implications for LC care in PLWH, offering a valid focus about this topic to clinicians.

Expanding Access to Lung Cancer Clinical Trials by Reducing the Use of Restrictive Exclusion Criteria: Perspectives of a Multistakeholder Working Group

Low rates of adult patient participation have been a persistent problem in cancer clinical trials and have continued to be a barrier to efficient drug development. The routine use of significant exclusion criteria has contributed to this problem by limiting participation in studies and creating significant clinical differences between the study cohorts and the real-world cancer patient populations. These routine exclusions also unnecessarily restrict opportunities for many patients to access potentially promising new therapies during clinical development. Multiple efforts are underway to broaden eligibility criteria, allowing more patients to enroll in studies and generating more robust data regarding the effect of novel therapies in the population at large. Focusing specifically on lung cancer as an example, a multistakeholder working group empaneled by the LUNGevity Foundation identified 14 restrictive and potentially outdated exclusion criteria that appear frequently in lung cancer clinical trials. As a part of the project, the group evaluated data from multiple recent lung cancer studies to ascertain the extent to which these 14 criteria appeared in study protocols and played a role in excluding patients (screen failures). The present report describes the working group's efforts to limit the use of these routine exclusions and presents clinical justifications for reducing the use of 14 criteria as routine exclusions in lung cancer studies, potentially expanding trial eligibility and improving the generalizability of the results from lung cancer trials.

Human immunodeficiency virus infection and mortality risk among lung cancer patients: A systematic review and meta-analysis

BACKGROUND

Previous studies have suggested that patients with human immunodeficiency virus (HIV) infection are at higher risk of lung cancer, but the impact of HIV infection on the risk of mortality among lung cancer patients is still unclear. We conducted a systematic review and meta-analysis to clarify the association between HIV infection and mortality risk among lung cancer patients.

METHODS

PubMed and Embase databases were searched to identify studies assessing the association between HIV infection and mortality risk among lung cancer patients. Only studies reporting adjusted relative risk (RR) of mortality among lung cancer patients with HIV infection were included. Meta-analysis of random-effect model was utilized to calculate the pooled RR with 95% confidence interval (CI).

RESULTS

Twelve cohort studies were finally included. Compared with lung cancer patients without HIV infection, the pooled RR of mortality among lung cancer patients with HIV infection was 1.48 (95% CI, 1.22-1.78, P < .001; I = 88.6%). After excluding 2 studies with low quality, HIV infection was still significantly associated with an elevated risk of mortality among lung cancer patients (RR = 1.51, 95% CI, 1.25-1.82, P < .001; I = 89.8%). Sensitivity analysis showed that the statistical significance of the pooled RR was not changed by excluding any one study.

CONCLUSION

The outcomes from the meta-analysis provide strong evidence for the elevated risk of mortality among lung cancer patients with HIV infection, and HIV infection is an important prognostic factor in lung cancer patients.

Pulmonary disease in HIV-infected adults in the era of antiretroviral therapy

: HIV in the antiretroviral therapy era is characterized by multimorbidity and the frequent occurrence of HIV-associated non-AIDS chronic health conditions. Respiratory symptoms and chronic pulmonary diseases, including chronic obstructive pulmonary disease, asthma, and cardiopulmonary dysfunction, are among the conditions that may present in persons living with HIV. Tobacco smoking, which is disproportionately high among persons living HIV, strongly contributes to the risk of pulmonary disease. Additionally, features associated with and at times unique to HIV, including persistent inflammation, immune cell activation, oxidative stress, and dysbiosis, may also contribute. This review summarizes the available literature regarding epidemiology of and risk factors for respiratory symptoms and chronic pulmonary disease in the current era.