RT Journal Article SR Electronic T1 Imaging the Different Mechanisms of Prostate Cancer Cell-killing by Tumor-targeting Salmonella typhimurium A1-R JF Anticancer Research JO Anticancer Res FD International Institute of Anticancer Research SP 5225 OP 5229 VO 35 IS 10 A1 AISADA UCHUGONOVA A1 YONG ZHANG A1 RENEE SALZ A1 FANG LIU A1 ATSUSHI SUETSUGU A1 LEI ZHANG A1 KARSTEN KOENIG A1 ROBERT M. HOFFMAN A1 MING ZHAO YR 2015 UL http://ar.iiarjournals.org/content/35/10/5225.abstract AB Background/Aims: We previously developed a genetically-modified bacterial strain of Salmonella typhimurium, auxotrophic for leucine and arginine, which also expresses green fluorescent protein (GFP), termed S. typhimurium A1-R. S. typhimurium A1-R was found to be effective against metastatic human prostate, breast, pancreatic, cervical and ovarian cancer, as well as osteosarcoma, fibrosarcoma and glioma, in clinically relevant nude mouse models. Materials and Methods: To understand the tumor cell-killing mechanism of S. typhimurium A1-R-GFP, we studied the interaction of S. typhimurium A1-R-GFP with three different prostate cancer cell lines in vitro. S. typhimurium-GFP invasion, proliferation, and means of killing in three different human prostate cancer cell lines were visualized by confocal fluorescence microscopy with the Olympus FV1000. Results: We found that S. typhimurium A1-R-induced cancer-cell death had different mechanisms in different prostate cancer cell lines, occurring through apoptosis and necrosis in the PC-3 prostate cancer cell line, and by cell bursting in the LNCaP and DU-145 prostate cancer cell lines. The time required for S. typhimurium A1-R-GFP to kill the majority of cancer cells varied from line to line, ranging from 2 hours to 48 hours. Conclusion: Understanding the various mechanisms of cancer-cell killing by S. typhimurium A1-R will be important for its use as a general therapeutic for cancer.