الفهرس | Only 14 pages are availabe for public view |
Abstract Hepatocellular carcinoma (HCC) is the third most frequent cause of death from cancer worldwide, which accounts for about 6% of all newly diagnosed cancer cases worldwide (Tagliamonte et al., 2016). Current therapies for early disease, which include liver transplantation, surgical resection or local ablation, do not lead to long-term cure in the majority of patients with advanced HCC (Chaparro et al., 2008). The immune evasion in HCC represents a main barrier to the delivery of an effective immunotherapy (Raufi and Tirona, 2017). Therefore, inhibiting the immune suppressive effect of cancer cells represents an important step in cancer immunotherapy. Although protocols differ, a common outline in immunotherapy is the activation of dendritic cells (DCs) in order to enhance antigen presentation. Studying the surface and molecular markers can aid in evaluating efficient immunotherapeutic tools (Wang et al., 2015). The present study aimed to enhance antigen presentation of tumor-associated antigens (TAAs) by attenuating liver cancer cells using ribonuclease A and subsequent co-culturing cancer cells with their autogenic or allogenic DCs and lymphocytes.HCC patients were fully diagnosed by means of clinical, radiological and laboratory examinations before being selected in the present work. Successful culturing of HCC core biopsy was approximately 15 out of 50 specimens which was therefore selected in the current study. Blood samples and liver core biopsy were obtained from fifteen newly diagnosed HCC patients. Peripheral blood mononuclear cells (PBMCs) were isolated and lymphocytes and monocytes were further isolated from the isolated PBMCs using tissue culture. Monocytes were then propagated and differentiated to immature dendritic cells. HCC explants were cultured in vitro to liberate cultured cancer cells. Cancer cells (HepG2 or patient’s HCC cells) were attenuated by ribonuclease A, meanwhile only HCC cells were treated with sorafenib and a group of untreated cells act as a control. Gene expressions of CD44, TAP-2, LMP-2, lactate dehydrogenase (LDH) and interleukin-12 levels in culture media supernatant and immunophenotypes of the cultured immune cells were evaluated. The results are summarized as follows: • Attenuating HepG2 cells with ribonuclease A and subsequent pulsation to allogenic immune cells showed a paradoxical effect on antigen presentation. • Attenuating HCC cells using ribonuclease A and subsequent pulsation to its autologous immune cells showed enhanced presentation of tumor associated antigens.• Treating HCC cells with sorafenib and subsequent pulsation to its autologous immune cells did not show significant change in antigen presentation. • Combination of ribonuclease A attenuation and sorafenib treatment of HCC cells showed the lowest antigen presentation confirming their antagonism. |