en Cancer Cancer Original Article Original Article <p><span style="font-size:11pt"><span style="line-height:107%"><span style="font-family:Calibri,sans-serif"><a name="_Hlk175498079"><span style="font-size:10.0pt"><span style="line-height:107%"><span new="" roman="" style="font-family:" times="">Esophageal </span></span></span></a><span style="font-size:10.0pt"><span style="line-height:107%"><span new="" roman="" style="font-family:" times="">cancer presents a challenge in gastroenterology and traditional chemotherapy and radiation therapy have less therapeutic activity with severe side effects. Thus, there is need for effective and safer alternatives. Probiotics, particularly <i>Lactobacillus plantarum</i> (<i>L</i>. <i>plantarum</i>) and its bacteriocins, might prevent or treat esophageal tumors. We aimed to investigate the use of <i>L. plantarum</i> and its bacteriocin as esophageal cancer therapy. First, we obtained 100 isolates of Lactobacillus spp. from dairy product samples. They screened for bacteriocin production and identified by PCR and gel electrophoresis for 16S ribosomal RNA gene. Bacteriocin was partially purified and tested against two different pathogens.&nbsp; Both L. plantarum and its bacteriocin were examined for cytotoxicity in vitro against esophageal cancer cell line (SK-GT4) and normal rat embryo fibroblast (REF) cells by MTT assay. Apoptosis was determined using an acridine orange /propidium iodide assay. The results showed that the isolate gives a high bacteriocin production about (2000AU/ml). In addition to antimicrobial activity, there was significant anticancer activity. <i>L</i>. <i>plantarum</i> had an IC₅₀ of 51.01 CFU/ml and bacteriocin IC₅₀ of 281.9 AU/ml against cancer cells. Both showed no cytotoxicity towards normal REF cells. Furthermore, there was a significant increase in apoptosis induction and in caspase-3 activity in cancer cells treated with L. plantarum and bacteriocin compared to untreated cells. In conclusion, <i>L. plantarum</i> and its bacteriocin show potent killing effect against esophageal cancer cells with no effect against normal cells indicating safety and selectivity with activation of apoptosis via caspase-3 induction suggesting potential clinical advantage.</span></span></span></span></span></span><br> <br> &nbsp;</p> Lactobacillus plantarum, Bacteriocin, antitumor activity, apoptosis, Gastro-intestinal tumors. 286 302 http://ijmcmed.org/browse.php?a_code=A-10-7999-1&slc_lang=en&sid=1 Salam Sabri sabrisalam99@gmail.com 100319475328460031496 100319475328460031496 No Department of Biology, Faculty of Sciences, Shahid Bahonar University of Kerman, Kerman, Iran. Saeed Esmaeili Mahani Semahani@uk.ac.ir 100319475328460031497 100319475328460031497 No Department of Biology, Faculty of Sciences, Shahid Bahonar University of Kerman, Kerman, Iran. Ahmed Majeed Al-Shammari alshammari.am@uomustansiriyah.edu.iq 100319475328460031498 100319475328460031498 Yes Experimental Therapy Department, Iraqi Center for Cancer and Medical Genetic Research, Mustansiriyah University, Baghdad, Iraq. Khalid Jaber Kadhum luti Khalid.kadhum@sc.uobaghdad.edu.iq 100319475328460031499 100319475328460031499 No Department of Biotechnology Science, College of Science, University of Baghdad, Baghdad, Iraq. Mehdi Abbas Nejad mabbas@uk.ac.ir 100319475328460031500 100319475328460031500 No Department of Biology, Faculty of Sciences, Shahid Bahonar University of Kerman, Kerman, Iran.