HIV/AIDS: epidemiology, pathophysiology, and treatment of Kaposi sarcoma-associated herpesvirus disease: Kaposi sarcoma, primary effusion lymphoma, and multicentric Castleman disease

Abstract

Kaposi sarcoma-associated herpesvirus infection is associated with the development of 3 proliferative diseases: Kaposi sarcoma, primary effusion lymphoma, and multicentric Castleman disease. These conditions are also intimately associated with human immunodeficiency virus infection, and important synergistic interactions between these 2 viruses have been described. Despite differences in viral gene expression patterns in each condition, Kaposi sarcoma-associated herpesvirus encodes similar oncogenic proteins that promote the activation of sequential and parallel signaling pathways. Therapeutic strategies have been implemented to target these unique signaling pathways, and this sort of molecular targeting is the focus of many current research efforts. The scope of this review is to present contemporary knowledge about the epidemiology, virology, and immunology of Kaposi sarcoma-associated herpesvirus and to highlight several key oncogene products that may be targets for chemotherapy.

Figure 1

Extensive papular/nodular Kaposi sarcoma on leg (Fig 1a) and back (Fig 1b) in a Uganda patient. (Fig1c) Cutaneous KS of plaque stage (H&E stain, magnification x 200) (Fig 1d) Kaposi sarcoma cutaneous tumor in which the spindled tumor cells demonstrate HHV8 immunoreactivity (LNA-1 immunohistochemical stain).

Figure 1

Extensive papular/nodular Kaposi sarcoma on leg (Fig 1a) and back (Fig 1b) in a Uganda patient. (Fig1c) Cutaneous KS of plaque stage (H&E stain, magnification x 200) (Fig 1d) Kaposi sarcoma cutaneous tumor in which the spindled tumor cells demonstrate HHV8 immunoreactivity (LNA-1 immunohistochemical stain).

Figure 2

Lymph node with HIV-associated MCD showing multiple regressing follicles surrounded by an expanded and vascular interfollicular zone (H&E stain, magnification x 100).

Figure 3

(Fig 3a) Pericardial primary effusion lymphoma (CT scan of the chest). (Fig 3b) Photomicrograph of pericardial fluid, cytospin preparation with atypical lymphoid cells with basophilic cytoplasm and vacuolization (Wright-Giemsa, original magnification x 600), Inset: prominent mitosis (arrow) in one of the lymphoma cells. (Fig 3c) HIV-associated PEL showing lymphoma cells with HHV8 viral nuclear inclusions (cell block preparation; H&E stain). [Figs 3a and 3b, copyright 2007, The AIDS Reader, CMPMedica., all rights reserved]

Figure 3

(Fig 3a) Pericardial primary effusion lymphoma (CT scan of the chest). (Fig 3b) Photomicrograph of pericardial fluid, cytospin preparation with atypical lymphoid cells with basophilic cytoplasm and vacuolization (Wright-Giemsa, original magnification x 600), Inset: prominent mitosis (arrow) in one of the lymphoma cells. (Fig 3c) HIV-associated PEL showing lymphoma cells with HHV8 viral nuclear inclusions (cell block preparation; H&E stain). [Figs 3a and 3b, copyright 2007, The AIDS Reader, CMPMedica., all rights reserved]

Figure 3

(Fig 3a) Pericardial primary effusion lymphoma (CT scan of the chest). (Fig 3b) Photomicrograph of pericardial fluid, cytospin preparation with atypical lymphoid cells with basophilic cytoplasm and vacuolization (Wright-Giemsa, original magnification x 600), Inset: prominent mitosis (arrow) in one of the lymphoma cells. (Fig 3c) HIV-associated PEL showing lymphoma cells with HHV8 viral nuclear inclusions (cell block preparation; H&E stain). [Figs 3a and 3b, copyright 2007, The AIDS Reader, CMPMedica., all rights reserved]