Molecular Study of Iraqi Patients with Brain Tumors Infection with HTLV-1

Abstract Background: HTLV-1 is associated with the chronic, persistent infection of T cells, which can result in neoplastic or inflammatory diseases; HTLV-1 indirectly damages the central nervous system to cause associated neuropathies starting with the virus crossing the blood–brain barrier, then enters and infects the cells of the central nervous system. Objectives: The study aimed to determine the percentage of HTLV-1 and estimate the genetic polymorphism of tumor necrosis factor-alpha (TNF-α), Killer-cell immunoglobulin-like receptor (KIR), and interleukin-1 receptor antagonist (IL-1Ra) genes in Iraqi patients with brain tumors and control groups. Materials and Methods: Case–control research has been carried out on (100) brain tissues enrolled in the current research, including (75) randomly selected brain tumors with different types and grades and (25) autopsies included as baseline control obtained from dead cases. The specimens were collected during the period from January 2022 to September 2022. Each participant provided tissue samples, which were then stored frozen at −80°C for RNA extraction and used in quantitative real-time polymerase chain reaction (PCR) and conventional PCR tests to detect the HTLV-I , TNF-α, KIR, and IL-1Ra genes. Results: Of 75 brain tumor specimens, 50 (66.7%) had a viral infection, whereas 25 (33.3%) specimens without a viral genome were detected in this study. According to the real-time PCR result for the (50) specimens with viral genome, the rate of HTLV-I infection was 42% (21 of 50). In contrast, the percentage of negative results was 58% (29 of 50). Gene polymorphisms of the TNF‑α‑G>T (rs1800629) and KIR2DS2 -A>T (rs78713511) genes have been associated with risk in the Iraqi patient with brain tumors, with significant differences ( P G (rs2234679) and 376C>T (rs16065) variants, respectively. Conclusion: Polymorphism of TNF-α and KIRs in Iraqi patients with brain tumors could point to that act as a risk factor in the pathogenesis of idiopathic brain tumors. Also, indicate that IL-1Ra might be a protective factor in Iraqi patients with brain tumors. The following conclusion leads to the idea that HTLV-1 acts as a cofactor in patients with brain tumors.