en Other Other Original article Original article <span style="font-size:11pt"><span style="line-height:normal"><span sans-serif="" style="font-family:Calibri,"><b><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times="">Introduction:</span></span></b><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times=""> According to global cancer statistics, oral cancer is the 11^th most prevalent cancer worldwide. Despite the availability of numerous modern treatments for oral cancer, a complete reduction of mortality rates has not been achieved</span></span><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times="">. Bacterial toxins have potential applications in inducing apoptosis or targeting tumor cells for destruction</span></span><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times="">. The present study aimed to investigate the impact of <i>Staphylococcus aureus</i> <i>seb</i> and <i>&alpha;-toxin</i> genes on apoptotic-related gene mRNA expression, as well as apoptosis induction in KB cell lines, focusing on <i>BAX</i>, <i>RB</i>, <i>BCL-2</i>, and <i>BAG-1</i> genes.<b> Methods: </b>The transfection of KB cells was performed using Lipofectamine 2000 to introduce pcDNA3.1 (+)-<i>seb</i>, pcDNA3.1 (+)-<i>&alpha;-toxin</i>, or an empty pcDNA3.1 (+) plasmid</span></span><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times="">. The cells were cultured in DMEM supplemented with 10% FBS and 800 mg/L of G418 to select cells containing the plasmids. Subsequently, real-time RT-PCR was performed to measure the mRNA expression levels of <i>BAX</i>, <i>RB</i>, <i>BCL-2</i>, and <i>BAG-1</i> genes</span></span><span style="font-size:10.0pt"><span style="font-family:" times-roman="">. Cell apoptosis was assessed using Annexin V/PI staining and flow cytometry</span></span><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times="">.</span></span><b><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times=""> Results:</span></span></b><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times=""> The <i>seb</i> and <i>&alpha;-toxin</i> significantly alter the expression of apoptotic-related genes in the KB cell line</span></span><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times="">. In transfected KB cells, there was a significant increase in the mRNA expression of <i>BAX</i> and <i>RB</i> genes and a substantial decrease in the mRNA expression of <i>BCL-2</i> and <i>BAG-1</i> compared to the control group. Annexin test and flow cytometry analysis revealed that <i>seb</i> was more effective than &alpha;-toxin in inducing apoptosis.</span></span><b><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times=""> Conclusions:</span></span></b><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times=""> The <i>seb</i> and <i>&alpha;-toxin</i> genes of <i>S. aureus</i> exhibit an inhibitory effect on the growth, proliferation, and invasion of oral cancer cells by modulating gene expression in the apoptotic pathway. Hence, these<i> </i>toxins are promising for controlling and treating human oral cancer</span></span></span></span></span> Staphylococcus aureus, enterotoxin type B, α-toxin, apoptosis, oral cancer, KB cell line, gene expression 96 102 http://jommid.pasteur.ac.ir/browse.php?a_code=A-10-376-3&slc_lang=en&sid=1 Milad Heidari milad.gnc@yahoo.com 0000-0001-8247-9729 Yes Shahrekord Branch, Islamic Azad University, Biotechnology Research Center, Shahrekord, Iran Abbas Doosti 0000-0001-8052-5963 No Shahrekord Branch, Islamic Azad University, Biotechnology Research Center, Shahrekord, Iran