Abstract 3184: Differential expression of viral agents in lymphoma tissues of patients with ABC diffuse large B-cell lymphoma from high and low endemic infectious disease region
Authors: Moshfegh Ali , Högfeldt Therese , Jaing Crystal , Lundahl Joachim , Osterborg Anders , Loughlin Kevin M. , Gardner Shea N. , Gharizadeh Baback , Porwit Anna , Bahnassy Abeer A. , Zekri Abdel-Rahman N. , Khaled Hussein M. , Mellstedt Hakan 
Published: May 2015

Environmental factors play an important role in the development of cancer. Infectious organisms are one of the major causes of cancer among environmental factors. Several viruses have been classified as infectious agents causing cancer as EBV, HTLV-1, herpes virus-8 and hepatitis. Since the introduction of vaccines against viral infections as HPV and HBV, the incidence of cervical cancer and HCC respectively has decreased.

The aim of the study was to investigate the detection of viral and microbial agents in the lymphoma tissues of ABC DLBCL patients from Sweden (low infectious disease region) and Egypt (high infectious disease region) according to WHO classification. Microbial detection array (MDA) technique was used to identify viral detection in the tissue samples as well as antigen and antibody detection of serum samples of patients.

A differential detection of viruses in lymphoma tissues was noted comparing Swedish and Egyptian patients. Viruses that were detected in all groups (both controls and patients) were excluded leaving exclusively found viruses in each group. HBV had the highest expression including the complete genome and was only found in Egyptian patients. JCV was found both in Egyptian and Swedish patients but with a higher expression in the Egyptian patients while not detected in Swedish and Egyptian controls. Generally, the highest expressions were found in Egyptian patients compared to Swedish patients and controls from both countries. Few viruses were found in the control groups.

Based on serum HBV PCR, Egyptian patients were divided into a HBV antigen positive (HBV+) and HBV negative (HBV-) group. The relative expression of STAT3 did not differ between HBV+ and HBV- Egyptian patients but was significantly higher in the Swedish patients compared to the total Egyptian patient population. Since, miR-1234 might regulate STAT3, we also related the relative miR-1234 expression to HBV status. There was no difference in the relative expression of miR-1234 between HBV+ and HBV- Egyptian patients, while Swedish patients (HBV-) showed a significantly lower relative expression of miR-1234, compared to the total Egyptian patient population. miR-1234 related inversely to the expression patterns of STAT3.

The results indicate that Egyptian patients have a higher viral load and that HBV was the most common virus. However, our results may be of importance for treatment strategies in Egyptian patients since previous data have shown HBV reactivation in patients from high endemic infectious area during Rituximab treatment.

In summary, indicated that viral agents as JCV and HBV may be involved in the tumorigenesis of ABC DLBCL. We could not detect a relation of STAT3 expression to HBV. However, the regulation of STAT3 by miR-1234 might be associated to other viral infections and to the higher viral load as noted in the Egyptian patients.

Citation Format: Ali Moshfegh, Therese Högfeldt, Crystal Jaing, Joachim Lundahl, Anders Osterborg, Kevin Mc Loughlin, Shea N. Gardner, Baback Gharizadeh, Anna Porwit, Abeer A. Bahnassy, Abdel-Rahman N. Zekri, Hussein M. Khaled, Hakan Mellstedt. Differential expression of viral agents in lymphoma tissues of patients with ABC diffuse large B-cell lymphoma from high and low endemic infectious disease region. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3184. doi:10.1158/1538-7445.AM2014-3184