Detection of Epstein-Barr virus encoded small RNA genes in oral squamous cell carcinoma and non-cancerous oral cavity samples

Abstract

Background Epstein-Barr Virus (EBV) is a human oncogenic virus that can lead to cancer in lymphoid and epithelial cells and is one of the hypothesized causes of oral cavity lesions including oral squamous cell carcinoma (OSCC), but the etiological association remains undetermined. The present investigation aimed to explore the EBV presence, viral load, and EBV-encoded small RNA (EBER) sequence variation in tissue samples of patients with OSCC and other oral cavity lesions including oral lichen planus (OLP), and oral irritation fibroma (OIF). Methods In total, 88 oral cavity samples (23 with OSCC, 29 with OLP, and 36 with OIF diagnosis) were examined by Real-Time PCR technique and some of them were sequenced. Results Viral EBER sequence was detected in 6 out of the 23 OSCC (31.4%), 6 out of the 29 OLP (20.7%), and 3 out of the 36 OIF cases (8.3%). The mean EBV copy number was higher in OSCC samples (1.2 × 10−2 ± 1.3 × 10−2 copies/cell) compared to OLP (2.2 × 10−3 ± 2.6 × 10−3 copies/cell) and OIF (2.4 × 10−4 ± 2.0 × 10−4 copies/cell) samples, although this difference was not statistically significant (P = 0.318). The EBER gene was amplified and sequenced in 5 OSCC, 3 OLP, and 2 OIF samples with high EBV viral load. One OSCC, two OLP, and two OIF isolates showed different nucleotide variations compared with EBV-WT and AG876 prototype sequences: C6834T, C6870T, C6981T, C7085T, C7085G, and C7094T. Conclusion In our study the presence of more than one genome copies per tumor cell indicates the possible role of EBV infection in oral cancers. However, more studies should be conducted to clarify the role of EBV in OSCC carcinogenesis.

Investigating the role of Epstein-Barr virus and human papillomavirus types 16 and 18 co-infections in cervical disease of Iranian women

“…The viral load of target genes was assessed by dividing the viral DNA copy number by half of the copy number of the RNase P gene, considering that each diploid cell contains two copies of the RNase P gene. Recombinant plasmids, containing the target gene sequences of HPV-16 E6 , HPV-18 E7 , and EBV EBER , along with the conserved region of the RNase-P cellular gene (Internal control), were prepared as real-time PCR standards based on previous studies ( 45 , 46 ). According to a previously established protocol, quantitative real-time PCR was performed using a Rotor-Gene ® Q real-time PCR system (QIAGEN GmbH, Hilden, Germany).…”

Oral microbiota and oral squamous cell carcinoma: a review of their relation and carcinogenic mechanisms

“…Human oncogenic virus EBV has been connected to the development of cancer in epithelial and lymphoid cells ( 111 ). However, it’s important to note that the relationship between past EBV infection and OSCC is not entirely clear.…”

Mechanisms and Potential Clinical Implications of Oral Microbiome in Oral Squamous Cell Carcinoma

“…Therefore, HNSCC is further divided into HPV-positive and HPV-negative types, which is conducive to exploring different causes and treatment options. The EBV is related to OSCC as well, as 55% of 155 OSCC samples from eight different countries and ethnicities were EBV-positive [30,31]. As to yeasts, Candida albicans is more prevalent in patients with oral cancer than in healthy people [32].…”