HIV+ MALT lymphoma remission induced by highly active antiretroviral therapy alone

Cytotoxic effect of Efavirenz in BxPC-3 pancreatic cancer cells is based on oxidative stress and is synergistic with ionizing radiation

The non-nucleoside reverse transcriptase inhibitor (NNRTI) Efavirenz is frequently used in human immunodeficiency virus treatment, but also efficient against cancer in mouse models. Its radiosensitizing effect makes it a promising drug for combination with radiotherapy. The efficacy of Efavirenz combined with irradiation was assessed with immunostaining of DNA-damage markers and colony formation assays in BxPC-3 pancreatic cancer cells. Gene expression and protein phosphorylation of the Efavirenz-sensitive BxPC-3 cells was compared to the resistant primary fibroblasts SBL-5. Oxidative stress, mitochondrial damage and cell death were studied with live-cell microscopy and flow cytometry. Combined Efavirenz and radiation significantly increased the number of γH2AX and phospho-ataxia telangiectasia mutated foci. Efavirenz and ionizing radiation had a synergistic effect using the clonogenic survival assay. Efavirenz selectively induced cell death in the BxPC-3 cells. The differing gene expression of cell cycle and apoptotic regulator genes in both cell cultures after Efavirenz treatment match with this selective effect against cancer cells. In the phosphoprotein array, an early phosphorylation of extracellular signal-related kinase 1/2 and p38 mitogen-activated protein kinase was notably detected in the cancer cells. The phosphorylation of AKT decreased in the cancer cells whereas it increased in the fibroblasts. Oxidative stress and mitochondrial membrane depolarization appeared in the cancer cells immediately after Efavirenz treatment, but not in the fibroblasts. Efavirenz has an anti-cancer effect against pancreatic cancer mainly by the induction of oxidative stress. The antitumor potential of Efavirenz and radiotherapy are additive.

Efavirenz Has the Highest Anti-Proliferative Effect of Non-Nucleoside Reverse Transcriptase Inhibitors against Pancreatic Cancer Cells

Background

Cancer prevention and therapy in HIV-1-infected patients will play an important role in future. The non-nucleoside reverse transcriptase inhibitors (NNRTI) Efavirenz and Nevirapine are cytotoxic against cancer cells in vitro. As other NNRTIs have not been studied so far, all clinically used NNRTIs were tested and the in vitro toxic concentrations were compared to drug levels in patients to predict possible anti-cancer effects in vivo.

Methods

Cytotoxicity was studied by Annexin-V-APC/7AAD staining and flow cytometry in the pancreatic cancer cell lines BxPC-3 and Panc-1 and confirmed by colony formation assays. The 50% effective cytotoxic concentrations (EC50) were calculated and compared to the blood levels in our patients and published data.

Results

The in vitro EC50 of the different drugs in the BxPC-3 pancreatic cancer cells were: Efavirenz 31.5μmol/l (= 9944ng/ml), Nevirapine 239μmol/l (= 63786ng/ml), Etravirine 89.0μmol/l (= 38740ng/ml), Lersivirine 543μmol/l (= 168523ng/ml), Delavirdine 171μmol/l (= 78072ng/ml), Rilpivirine 24.4μmol/l (= 8941ng/ml). As Efavirenz and Rilpivirine had the highest cytotoxic potential and Nevirapine is frequently used in HIV-1 positive patients, the results of these three drugs were further studied in Panc-1 pancreatic cancer cells and confirmed with colony formation assays. 205 patient blood levels of Efavirenz, 127 of Rilpivirine and 31 of Nevirapine were analyzed. The mean blood level of Efavirenz was 3587ng/ml (range 162–15363ng/ml), of Rilpivirine 144ng/ml (range 0-572ng/ml) and of Nevirapine 4955ng/ml (range 1856–8697ng/ml). Blood levels from our patients and from published data had comparable Efavirenz levels to the in vitro toxic EC50 in about 1 to 5% of all patients.

Conclusion

All studied NNRTIs were toxic against cancer cells. A low percentage of patients taking Efavirenz reached in vitro cytotoxic blood levels. It can be speculated that in HIV-1 positive patients having high Efavirenz blood levels pancreatic cancer incidence might be reduced. Efavirenz might be a new option in the treatment of cancer.

Cytotoxic effect of efavirenz is selective against cancer cells and associated with the cannabinoid system

BACKGROUND

Recently, a regression of precancerous lesions in HIV-1-infected patients after initiation of HAART was reported. Nonnucleoside reverse transcriptase inhibitors (NNRTIs) as efavirenz (EFV) might be mediators of this effect, as they are known to have a cytotoxic effect on tumour cells. A potential mechanism involved in this effect may be the activation of the cannabinoid receptor to mediate tumour toxicity.

METHODS

Several tumour-derived and fibroblast cell lines were studied. Cytotoxicity of EFV was evaluated by Annexin-Pi staining. The expression of the cannabinoid receptors CB1, CB2 and GPR55 was analysed by western blot, quantitative reverse transcriptase (qRT-PCR) and fluorescence activated cell sorting. The influence of the cannabinoid agonists and antagonists on the effects of EFV was investigated. Furthermore, the effect of EFV on the phosphorylation state of the growth factors Erk, Akt and the tumour suppressor protein p53 was tested.

RESULTS

EFV revealed a selective cytotoxic effect on several tumour cell lines, whereas primary fibroblasts were not affected. The cytotoxic effect was associated with the expression of CB1. The combination of EFV with cannabinoid agonists showed an increase in toxicity. The phosphorylation state of Erk and Akt was not affected by EFV, whereas p53 showed an increased phosphorylation.

CONCLUSION

EFV has a selective cytotoxic effect on several tumour cells. Furthermore, EFV led to an activating phosphorylation of the tumour suppressor protein p53 going in line with earlier reports that EFV may be antitumourigenic and a potential cytostatic drug. The observed synergistic effect with cannabinoid agonists implicates an involvement of the cannabinoid system.

Characteristics of B-cell lymphomas in HIV/HCV-coinfected patients during the combined antiretroviral therapy era: an ANRS CO16 LYMPHOVIR cohort study

Hepatitis C virus (HCV) infection is frequent among HIV-infected patients. We describe, the characteristics of 6 HIV/HCV-coinfected patients with B-cell non-Hodgkin lymphoma (NHL) included in a prospective cohort study of HIV-related lymphomas. Five of the 6 cases had features of marginal zone/lymphoplasmacytic NHL versus 1 of 33 HIV only-infected patients. Remarkably, anti-HCV treatment led to a hematological response in a patient with splenic marginal zone lymphoma. This supports the role of chronic antigenic stimulation by HCV on lymphomagenesis and further evaluation of HCV antiviral therapy in coinfected patients with NHL.

Immunopathologic differences of Sjögren's syndrome versus sicca syndrome in HCV and HIV infection

A clinical picture of dry eye and dry mouth with the histological counterpart of focal lymphocytic sialoadenitis, usually detected in minor salivary glands, is considered the hallmark of Sjögren's syndrome. The association of sicca complaints and focal sialoadenitis can be also found in a number of other diseases, including some systemic viral infections. Among these conditions, chronic hepatitis C virus infection, associated with mixed cryoglobulinaemia and extra-hepatic manifestations, and HIV infection, particularly in the phase of diffuse interstitial lymphocytic infiltration, may mimic the clinical and histological aspects of Sjögren's syndrome. However, each disorder is characterised by specific, disease-related immunopathological aspects. Besides sicca complaints, the various disorders may also share a number of systemic extra-glandular features and the possible development of mucosa-associated lymphoid tissue lymphomas. This latter event represents in all of these diseases the final result of an antigen-driven chronic stimulation of B lymphocytes.

GI-lymphomas in immunosuppressed patients (organ transplantation; HIV)

Gastrointestinal lymphoma plays a major role complicating different diseases presenting with immunosuppression, both primary and acquired immunodeficiency (incl. HIV, transplantation, immunosuppression following chemotherapy, or inflammatory bowel disease). Lymphoma in diseases with immunosuppression are clinically and pathologically heterogeneous, but share some features such as frequent involvement of extranodal sites, diffuse aggressive histology, B-cell lineage derivation, viral association with EBV and clinically aggressive courses. While gastrointestinal lymphoma in congenital immunodeficiency disorders seems to be a rare event inspite of higher prevalences, in post-transplant lymphoproliferative disorders (PTLD) the gastrointestinal tract is one of the most important organs of lymphoma. In HIV-associated non-Hodgkin's lymphoma, gastrointestinal lesions as the most frequent extranodal localisation occur in 30-50% of lymphoma patients, are late events of HIV infection with severe immunosuppression and are mainly diagnosed with advanced disease stages Ann Arbour III or IV. They are characterised by unusual, often multifocal localisation in the gastrontestinal tract, high rates of life-threatening complications (bleeding, perforation or obstruction) and high-grade B-cell histology. With the introduction of highly active antiretroviral therapy (HAART) in the therapeutic concept in AIDS, a decrease of AIDS-related GI lymphoma was noted with improved survival rates and prognosis of lymphoma. Therapy strategies including chemotherapy, immunotherapy and HAART will show promising results in response and survival rates.

Long-term complete regression of nodal marginal zone lymphoma transformed into diffuse large B-cell lymphoma with highly active antiretroviral therapy alone in human immunodeficiency virus infection

Since the introduction of combination antiretroviral therapy (cART), there has been a decrease in the incidence of non-Hodgkin lymphoma among the HIV-infected population and also significantly improved survival rates. We describe a remarkable case of a HIV-infected patient whose large B-cell lymphoma, most likely arising by transformation of a nodal marginal zone lymphoma, completely regressed with the use of cART alone. He remained disease-free for almost 3 years and he finally died from presumed flare up of his lymphoma. There are very few cases of spontaneous regression of lymphomas with cART alone in the HIV population. This is an extreme example of the significance of cART in improving survival in HIV-non-Hodgkin lymphoma and changing the face of the HIV epidemic in general.

Update on HIV lymphoma

In industrialized nations people infected with HIV remain at increased risk for malignancies despite highly active antiretroviral therapy. In these countries, lymphoma is the most common HIV-associated malignancy. This review summarizes progress from January 2005 to February 2007. The majority of investigation has been in diffuse large B cell lymphoma, with infusional therapy remaining promising but cumbersome. Rituximab likely improves complete response rates, and, possibly overall survival, but is likely associated with increased infections in a subset of patients with very low CD4 counts. Biologic insights have been attained in the spectrum of HIV-associated non-Hodgkin's lymphoma, Hodgkin's lymphoma, and virologic coinfections. Overall, the outcome for non-Hodgkin's lymphoma and Hodgkin's lymphoma in the setting of HIV continues to improve as insights into the pathophysiology and treatment advance.

Non-Hodgkin's lymphoma of mucosa-associated lymphoid tissue

The concept of mucosa-associated lymphoid tissue (MALT) lymphomas was introduced by Isaacson and Wright [Cancer 1983; 52:1410-1416] in 1983. After more than 20 years of clinical research MALT lymphomas are now recognized as a distinct subtype of non-Hodgkin's lymphoma (NHL) with unique pathogenic, histological, and clinical features. Although this subtype of NHL occurs frequently, optimal management remains elusive. This manuscript reviews features of the clinical presentation, diagnosis, pathology, molecular characteristics, and management of both gastric and non-gastric MALT lymphoma.

Update in HIV lymphoma

PURPOSE OF REVIEW

Despite the control of HIV infection in industrialized nations, individuals infected with HIV remain at increased risk of malignancies. Lymphoma is the most common HIV-associated malignancy in these countries. This review summarizes progress from January 2005 to March 2006.

RECENT FINDINGS

Investigators continue to demonstrate that HIV-associated non-Hodgkin's lymphoma remains a significant problem, even in the era of highly active antiretroviral therapy. The majority of work has been in diffuse large B-cell lymphoma, with infusional therapy remaining promising, and rituximab an area of investigation. The latter improves complete response rates, but is associated with an increased incidence of infections. Biological insights have been gained into the spectrum of HIV-associated non-Hodgkin's lymphoma and Hodgkin's disease, and include further work on virological co-infections.

SUMMARY

The outcome for individuals infected with HIV and developing non-Hodgkin's lymphoma and Hodgkin's disease continues to improve as insights into the pathophysiology and treatment advance.

Lymphome pulmonaire du MALT révélant un sida

INTRODUCTION

We report the case of a patient with an isolated pulmonary mucosa associated lymphoid tissue (MALT) lymphoma that revealed an acquired immune deficiency syndrome (AIDS).

CASE REPORT

A 30 year old man from Central Africa was admitted to hospital with cough, dyspnoea and general weakness. A diagnosis of HIV infection was made promptly. The thoracic CT scan revealed diffuse bilateral ground glass opacities as well as consolidation of the right upper lobe. After a non-diagnostic endoscopy the diagnosis of a low grade B cell MALT lymphoma (CD20+) was made by lung biopsy and confirmed by the presence of the t(11;18) translocation. No extrathoracic lymphoma was found. Treatment with rituximab and triple anti-retroviral therapy led to a rapid and complete remission that was maintained for 3 years after the diagnosis.

CONCLUSION

Pulmonary MALT lymphoma may reveal AIDS. A combination of rituximab and anti-retroviral therapy led to complete remission in this patient.