Comparison of TGF-β, IL-10 levels and LMP-1 in gastric and oropharyngeal carcinoma associated with EBV infection

Increasing interest has been focused on the Epstein-Barr Virus (EBV)-associated cancers, including oropharyngeal cancer (OPC) and gastric cancer (GC). Different cytokines, growth factors and proteins take part in oncogenesis. The aim of our study was to generate a comparison of interleukin 10 (IL-10) and transforming growth factor β (TGF-β) levels, as well as latent membrane protein (LMP-1), Epstein-Barr virus capsid antigen (EBVCA), Epstein-Barr virus nuclear antigen (EBNA) and early antigen (EA) frequency in the serum of patients with GC and OPC. The study involved 50 patients with diagnosed GC and 50 patients with OPC. All studied patients were EBV positive. Fresh-frozen tumor tissue fragments were tested using nested PCR assay for EBV DNA detection. Sera from all individuals were investigated using ELISA tests to detect the presence of EBVCA IgG, EBNA IgG, EA IgG, as well as to determine the levels of IL-10 and TGF-β. The obtained results were subjected to statistical analysis. In patients with GC, the levels of TGF-β and IL-10 were significantly higher than in OPC patients. However, the frequency and level of EBVCA, EBNA and EA in patients with OPC and GC were not significantly different. In contrast, TGF-β and IL-10 levels were significantly higher in EBVaGC, as compared to OPC, suggesting their role in gastric carcinogenesis. The differences in frequency of LMP-1 detection in patients with OPC and GC may suggest different mechanism of oncogenesis. Further studies are required to clarify the role of Epstein-Barr virus in cancer development

The role of toll-like receptor 9 (TLR9) in Epstein-Barr virus-associated gastric cancer

Epstein-Barr virus-associated gastric carcinoma (EBVaGC) is the most common malignancy caused by EBV infection. Toll-like receptors (TLRs) as major components of innate immune system are crucial in the development of inflammatory processes and carcinogenesis. The aim of our study was to evaluate tissue and serum level of TLR9 in EBV-positive and EBV-negative gastric cancer patients. The study involved 30 EBV(+) and 30 EBV(-) patients. EBV DNA was detected in fresh frozen tumor tissue. In serum samples TLR9 level, transforming growth factor β (TGFβ), interleukin 10 (IL-10) and antibodies against EBV were detected using ELISA tests. TLR9 level was also measured in homogenate of tumour tissue. TLR9 level was statistically lower in EBV(+) patients both in serum and tissue, with statistically higher level in tissue than in serum. Lower level of TLR9 was accompanied by higher level of Epstein-Barr virus capsid antigen (EBVCA), Epstein-Barr virus nuclear antigen (EBNA) and early antigen (EA). A lower level of TLR9 was detected in patients with poorly differentiated cancer (G3) and greater lymph nodes involvement (N3-N4). Lower level of TLR9 in patients with EA may point to TLR9 role in reactivation of EBV infection