Induction of interleukin-1 and glucocorticoid hormones by HIV promotes viral replication and links human chromosome 2 to AIDS pathogenesis: genetic mechanisms and therapeutic implications

Involvement of Alarmins in the Pathogenesis and Progression of Multiple Myeloma

OBJECTIVE

Multiple Myeloma (MM) is a haematological disease resulting from the neoplastic transformation of plasma cells. The uncontrolled growth of plasma cells in the bone marrow and the delivery of several cytokines causes bone erosion that often does not regress, even in the event of disease remission. MM is characterised by a multi-step evolutionary path, which starts with an early asymptomatic stage defined as monoclonal gammopathy of undetermined significance (MGUS) evolving to overt disease.

DATA SOURCES AND STUDY SELECTION

We have selected scientific publications on the specific topics "alarmis, MGUS, and MM", drawing from PubMed. The keywords we used were alarmines, MGUS, MM, and immune system.

RESULTS

The analysis confirms the pivotal role of molecules such as high-mobility group box-1, heat shock proteins, and S100 proteins in the induction of neoangiogenesis, which represents a milestone in the negative evolution of MM as well as other haematological and non-haematological tumours.

CONCLUSIONS

Modulation of the host immune system and the inhibition of neoangiogenesis may represent the therapeutic target for the treatment of MM that is capable of promoting better survival and reducing the risk of RRMM.

Lymphocyte Subsets and Inflammatory Cytokines of Monoclonal Gammopathy of Undetermined Significance and Multiple Myeloma

Almost all multiple myeloma (MM) cases have been demonstrated to be linked to earlier monoclonal gammopathy of undetermined significance (MGUS). Nevertheless, there are no identified characteristics in the diagnosis of MGUS that have been helpful in differentiating subjects whose cancer may progress to a malignant situation. Regarding malignancy, the role of lymphocyte subsets and cytokines at the beginning of neoplastic diseases is now incontestable. In this review, we have concentrated our attention on the equilibrium between the diverse lymphocyte subsets and the cytokine system and summarized the current state of knowledge, providing an overview of the condition of the entire system in MGUS and MM. In an age where the therapy of neoplastic monoclonal gammopathies largely relies on drugs capable of acting on the immune system (immunomodulants, immunological checkpoint inhibitors, CAR-T), detailed knowledge of the the differences existing in benign and neoplastic forms of gammopathy is the main foundation for the adequate and optimal use of new drugs.

HIV-1 accessory protein Vpr: relevance in the pathogenesis of HIV and potential for therapeutic intervention

The HIV protein, Vpr, is a multifunctional accessory protein critical for efficient viral infection of target CD4⁺ T cells and macrophages. Vpr is incorporated into virions and functions to transport the preintegration complex into the nucleus where the process of viral integration into the host genome is completed. This action is particularly important in macrophages, which as a result of their terminal differentiation and non-proliferative status, would be otherwise more refractory to HIV infection. Vpr has several other critical functions including activation of HIV-1 LTR transcription, cell-cycle arrest due to DCAF-1 binding, and both direct and indirect contributions to T-cell dysfunction. The interactions of Vpr with molecular pathways in the context of macrophages, on the other hand, support accumulation of a persistent reservoir of HIV infection in cells of the myeloid lineage. The role of Vpr in the virus life cycle, as well as its effects on immune cells, appears to play an important role in the immune pathogenesis of AIDS and the development of HIV induced end-organ disease. In view of the pivotal functions of Vpr in virus infection, replication, and persistence of infection, this protein represents an attractive target for therapeutic intervention.

Glucocorticoids suppress human immunodeficiency virus type-1 long terminal repeat activity in a cell type-specific, glucocorticoid receptor-mediated fashion: direct protective effects at variance with clinical phenomenology

Glucocorticoid administration and/or excess secretion have been associated with increased Human Immunodeficiency Virus Type-1 (HIV-1) replication and AIDS progression. The HIV-1 long terminal repeat (LTR) promoter contains glucocorticoid-responsive element (GRE)-like sequences that could mediate a positive effect of glucocorticoids on HIV-1. In addition, we recently demonstrated that the HIV-1 accessory protein Vpr is a potent coactivator of the glucocorticoid receptor, which, like the host coactivator p300, potentiates the effect of glucocorticoids on GRE-containing, glucocorticoid-responsive genes. Such an effect may increase the sensitivity of several host target tissues to glucocorticoids by several fold, and may, thus, contribute to a positive effect of glucocorticoids on the HIV-1-LTR in infected host cells. In this study, we determined the direct effect of glucocorticoids on HIV-1-LTR by examining the ability of dexamethasone to modulate the activity of this promoter coupled to the luciferase reporter gene in human cell lines. Dexamethasone markedly inhibited Tat-stimulated, p300- or Vpr-enhanced luciferase activities in a cell-type specific, dose-dependent, and glucocorticoid receptor-mediated fashion. This effect of dexamethasone was not potentiated by Vpr, was antagonized by the glucocorticoid receptor antagonist RU 486 and required the DNA-binding domain of the receptor. These data suggest that the inhibitory effect of glucocorticoids on the HIV-1-LTR may be exerted via non-GRE-dependent inhibition of the strongly positive host transcription factor NF-kappaB, which interacts with the DNA- and ligand-binding domains of the receptor. Alternatively, it is also possible that dexamethasone-activated glucocorticoid receptor competes with other transcription factors for their binding sites on the promoter region or squelches transcription factors shared by HIV-1-LTR and glucocorticoid-responsive promoters. We conclude that glucocorticoids suppress, rather than stimulate, the HIV-1 promoter, thus acting, protectively for the host. Their apparent negative clinical association with AIDS is most likely due to immunosuppression of the host.

Interleukin-1 receptor antagonist as a treatment of HIV infection

The human immunodeficiency virus (HIV) apparently utilizes human chromosome 2, interleukin-1 (IL-1), glucocorticoid hormones, and viral Tat protein to accelerate its replication and the synthesis of all HIV proteins. HIV Tat protein binds to the long terminal repeat (LTR) ribonucleic acid, including the trans-acting responsive (TAR) sequence and the promoter region to increase HIV replication. Tat-TAR transactivation requires a factor encoded on the long arm of chromosome 2. The interaction of HIV with chromosome 2 may also cause the observed inhibition of interleukin-1 receptor antagonist (IL-1RA), thus increasing the production of IL-1. IL-1, in turn, stimulates the HIV-1 enhancer region of the LTR, thus increasing HIV gene expression and replication. IL-1 also induces glucocorticoid hormone synthesis which stimulates HIV in the virion infectivity factor (Vif) region, thus increasing HIV infectivity. It is, thus, proposed that IL-1RA not only may serve to inhibit HIV-induced IL-1, but may be the unidentified human chorionic gonadotropin-associated factor recently found to have anti-HIV and anti-Kaposi's sarcoma activity.

The role of interleukin-1 beta in the pathogenesis of multiple myeloma

Interleukin-1 beta has potent OAF activity, can increase the expression of adhesion molecules, and can induce paracrine IL-6 production (see Fig. 1). These biologic effects of IL-1 beta closely parallel several of the clinical features of human myeloma, such as osteolytic bone lesions, homing of myeloma cells to the bone marrow, and IL-6-induced cell growth. The increased production of adhesion molecules could explain why myeloma cells are found predominantly in the bone marrow. These fixed monoclonal plasma cells could subsequently stimulate osteoclasts through the production of IL-1 beta and paracrine generation of IL-6, resulting in osteolytic disease. Also, IL-6 produced by either a paracrine or autocrine mechanism can support the growth of the myeloma cells that may be manifested clinically by an elevated labeling index. In the future, continued follow-up of IL-1 beta-positive and IL-1 beta-negative MGUS patients should determine whether aberrant expression of IL-1 beta by monoclonal plasma cells is a critical genetic event in the progression of MGUS to myeloma. Because MGUS is relatively common in the general population and myeloma is incurable in almost all cases, identification of MGUS patients who are likely to progress to active myeloma will be important in the development of new therapeutic strategies. For example, an effective chemopreventive agent that prevents or delays the transition from MGUS to myeloma could have a major effect on the treatment of patients with monoclonal gammopathies.

Comparison of Interleukin-1β Expression by In Situ Hybridization in Monoclonal Gammopathy of Undetermined Significance and Multiple Myeloma

We investigated whether interleukin-1β (IL-1β) is differentially expressed in plasma cells from monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma (MM) patients because IL-1β appears to play a major role in the development of lytic bone lesions, the major clinical feature distinguishing MGUS from myeloma. In situ hybridization (ISH) for IL-1β was performed using bone marrow aspirates from 51 MM, 7 smoldering MM, 21 MGUS, and 5 normal control samples. Using the ISH technique IL-1β mRNA was detectable in the plasma cells from 49 of 51 patients with active myeloma and 7 of 7 patients with smoldering myeloma. In contrast, 5 of 21 patients with MGUS and 0 of 5 normal controls had detectable IL-1β message. Bone lesions were present in 40 of the 51 MM patients analyzed, and all 40 patients had IL-1β mRNA by ISH. These results show that greater than 95% of MM patients but less than 25% of MGUS patients are positive for IL-1β production. In the future, continued follow-up of IL-1β positive and negative MGUS patients should determine whether aberrant expression of plasma cell IL-1β is predictive of those MGUS patients that will eventually progress to active myeloma.

Comparison of Interleukin-1β Expression by In Situ Hybridization in Monoclonal Gammopathy of Undetermined Significance and Multiple Myeloma

We investigated whether interleukin-1β (IL-1β) is differentially expressed in plasma cells from monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma (MM) patients because IL-1β appears to play a major role in the development of lytic bone lesions, the major clinical feature distinguishing MGUS from myeloma. In situ hybridization (ISH) for IL-1β was performed using bone marrow aspirates from 51 MM, 7 smoldering MM, 21 MGUS, and 5 normal control samples. Using the ISH technique IL-1β mRNA was detectable in the plasma cells from 49 of 51 patients with active myeloma and 7 of 7 patients with smoldering myeloma. In contrast, 5 of 21 patients with MGUS and 0 of 5 normal controls had detectable IL-1β message. Bone lesions were present in 40 of the 51 MM patients analyzed, and all 40 patients had IL-1β mRNA by ISH. These results show that greater than 95% of MM patients but less than 25% of MGUS patients are positive for IL-1β production. In the future, continued follow-up of IL-1β positive and negative MGUS patients should determine whether aberrant expression of plasma cell IL-1β is predictive of those MGUS patients that will eventually progress to active myeloma.

Biology of the Transition of Monoclonal Gammopathy of Undetermined Significance (MGUS) to Multiple Myeloma

BACKGROUND: Approximately 25% of patients with monoclonal gammopathy of undetermined significance (MGUS) eventually develop multiple myeloma (MM) or a related plasma cell disorder that is universally fatal. In this report, we examine the changes that occur in the clonal plasma cell that are likely to be important in the progression of MGUS to active myeloma. METHODS: Studies that investigate the mechanisms involved in the multistep pathogenesis of monoclonal gammopathies are reviewed. Cytokines such as IL-6 and IL-1-beta, adhesion molecules, viruses, and oncogenes including ras, bcl-2, Rb, and p53 are discussed. RESULTS: IL-1-beta is produced by plasma cells from virtually all MM patients but is undetectable in most MGUS patients. IL-1-beta has potent osteoclast activating factor activity, can increase the expression of adhesion molecules, and can induce paracrine IL-6 production. The increased production of adhesion molecules could explain why myeloma cells are found predominantly in the bone marrow. Subsequently, these "fixed" monoclonal plasma cells could now stimulate osteoclasts through the production of IL-1-beta and paracrine generation of IL-6 resulting in osteolytic disease. With continued progression of the myeloma, the monoclonal plasma cells may later acquire the ability to produce IL-6 in an autocrine fashion that will be manifested clinically by an elevated labeling index. CONCLUSIONS: A better understanding of the progression of MGUS to myeloma may lead to novel therapeutic strategies to prevent the development of MM.