Exploring the Role of IL-32 in HIV-Related Kaposi Sarcoma

  • George Semango
  • , Bas Heinhuis
  • , Theo S Plantinga
  • , Willeke A M Blokx
  • , Gibson Kibiki
  • , Tolbert Sonda
  • , Daudi Mavura
  • , Elisante J Masenga
  • , Mramba Nyindo
  • , Andre J A M van der Ven
  • , Leo A B Joosten

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

The intracellular proinflammatory mediator IL-32 is associated with tumor progression; however, the mechanisms remain unknown. We studied IL-32 mRNA expression as well as expression of other proinflammatory cytokines and mediators, including IL-1α, IL-1β, IL-6, IL-8, tumor necrosis factor (TNF)-α, the proangiogenic and antiapoptotic enzyme cyclooxygenase-2, the IL-8 receptor C-X-C chemokine receptor (CXCR) 1, and the intracellular kinase focal adhesion kinase-1. The interaction of IL-32 expression with expression of IL-6, TNF-α, IL-8, and cyclooxygenase-2 was also investigated. Biopsy specimens of 11 HIV-related, 7 non-HIV-related Kaposi sarcoma (KS), and 7 normal skin tissues (NSTs) of Dutch origin were analyzed. RNA was isolated from the paraffin material, and gene expression levels of IL-32 α, β, and γ isoforms, IL1a, IL1b, IL6, IL8, TNFA, PTGS2, CXCR1, and PTK2 were determined using real-time quantitative PCR. Significantly higher expression of IL-32β and IL-32γ isoforms was observed in HIV-related KS biopsy specimens compared with non-HIV-related KS and NST. The splicing ratio of the IL-32 isoforms showed IL-32γ as the highest expressed isoform, followed by IL-32β, in HIV-related KS cases compared with non-HIV-related KS and NST. Our data suggest a possible survival mechanism by the splicing of IL-32γ to IL-32β and also IL-6, IL-8, and CXCR1 signaling pathways to reverse the proapoptotic effect of the IL-32γ isoform, leading to tumor cell survival and thus favoring tumor progression.

Original languageEnglish
Pages (from-to)196-203
Number of pages8
JournalAmerican Journal of Pathology
Volume188
Issue number1
DOIs
Publication statusPublished - Jan 2018
Externally publishedYes

Keywords

  • Apoptosis/genetics
  • Chemokines, CXC/metabolism
  • Cyclooxygenase 2/metabolism
  • Cytokines/metabolism
  • Disease Progression
  • HIV Infections/complications
  • Humans
  • Interleukins/metabolism
  • Sarcoma, Kaposi/metabolism
  • Signal Transduction/physiology
  • Skin Neoplasms/metabolism
  • Skin/metabolism

Fingerprint

Dive into the research topics of 'Exploring the Role of IL-32 in HIV-Related Kaposi Sarcoma'. Together they form a unique fingerprint.

Cite this