A 40-year-old man presents with multiple violaceous skin nodules on the trunk and oral cavity. He is HIV-positive with a CD4 count of 80 cells/μL. Biopsy shows spindle-shaped cells and slit-like vascular spaces. HHV-8 is detected by PCR. Which viral protein of HHV-8 is primarily responsible for driving angiogenesis in this lesion?

• A Latency-associated nuclear antigen (LANA)
• B Viral cyclin (v-cyclin)
• C Viral G protein-coupled receptor (vGPCR) ✓
• D Viral FLICE inhibitory protein (vFLIP)

Explanation

The patient has Kaposi sarcoma caused by HHV-8. The viral GPCR (vGPCR) is a constitutively active homolog of cellular GPCRs that activates the VEGF pathway, driving angiogenesis and spindle cell proliferation. LANA maintains episomal latency. v-cyclin drives cell cycle. vFLIP inhibits apoptosis. All contribute to oncogenesis but vGPCR is the key angiogenic driver.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.