Co-presence of Epstein–Barr virus and high-risk human papillomaviruses in Syrian colorectal cancer samples

Abstract

We recently performed two studies exploring the presence of Epstein-Barr virus (EBV) and high-risk human papillomaviruses (HPVs) types 16, 18, 31, 33 and 35 in human colorectal cancers from the Syrian population. Herein, we report that EBV and high-risk HPVs are co-present in colorectal cancers from Syria. We reveal that 17 (~17%) of 102 cancer samples are positive for both EBV and high-risk HPVs and their copresence is associated with high/intermediate grade invasive carcinomas. These data suggest that EBV and high-risk HPVs are co-present in human colorectal cancers where they might cooperate on the initiation and/or progression of these cancers. Thus, we believe that future studies are necessary to confirm the co-presence of these oncoviruses and their cooperative role in human colorectal carcinogenesis.

Does human papillomavirus cause human colorectal cancer? Applying Bradford Hill criteria postulates

“…Polymerase chain reaction (PCR) technique was employed by most of the studies [ 8 , 10 , 11 , 13 , 17 - 35 , 37 – 49 , 52 , 54 , 55 , 57 – 91 ] to detect the presence of HPV in the normal, adjacent/benign and diseased samples using L1, E6 and E7 gene-specific primers which specifically target [ 6 , 11 , 16 , 18 , 31 , 33 , 35 , 39 , 40 , 42 , 45 , 51 – 59 ] the subtypes of HPV, and from them, in addition, few studies also employed the second techniques including immunohistochemistry [ 67 ] and Southern blotting [ 13 , 28 ] to validate their PCR results.…”

“…Few studies also used immunohistochemistry [ 31 , 36 , 51 , 56 ], gene chip technology [ 53 ], Southern blotting [ 50 ] and in situ hybridisation [ 12 ] for the detection of HPV, and they did not validate their results through any other technique.…”

“…So far, in Syria, the association between HPV and CRC has been accessed by only two studies [ 31 , 70 ]. These studies utilised immunohistochemistry and PCR techniques for HPV detection with primers specific for L1, E6 and E7 regions of the viral genome and documented HPV detection positivity ratios in varying frequencies ranging from 36.2% [ 31 ] to 53.8% [ 70 ] in CRC samples ( Table 1 ).…”

High-Risk Human Papillomaviruses and Epstein–Barr Virus in Colorectal Cancer and Their Association with Clinicopathological Status

“…The tumors were considered positive for E6 and LMP1 if cancer cells exhibited positivity ≥1% of the cells [ 69 ]. In the case of LMP1 protein expression, we also evaluated the presence of viral infection in tumor-infiltrating lymphocytes and stromal cells [ 69 , 70 ].…”

Co-incidence of Human Papillomaviruses and Epstein–Barr Virus Is Associated With High to Intermediate Tumor Grade in Human Head and Neck Cancer in Syria

“…Moreover, it has been reported that the co-occurrence of high-risk HPVs and EBV in oral cancer is associated with a significant increase in the invasiveness ability of cancer cells ( 25 ). We recently demonstrated that the co-presence of high-risk HPVs and EBV is linked to high/intermediate grade in different types of human carcinomas including HN ( 5 , 26 , 27 ). Thus, it is evident that the co-presence of high-risk HPVs and EBV in high-grade human carcinomas could suggest a possible cooperation between their oncoproteins; however, there are only few studies regarding the co-presence of high-risk HPVs and EBV in the ME region focusing only on NPCs.…”