Tumor-specific cell-cycle decoy by Salmonella typhimurium A1-R combined with tumor-selective cell-cycle trap by methioninase overcome tumor intrinsic chemoresistance as visualized by FUCCI imaging.
We previously reported real-time monitoring of cell cycle dynamics of cancer cells throughout a live tumor intravitally using a fluorescence ubiquitination cell cycle indicator (FUCCI). Approximately 90% of cancer cells in the center and 80% of total cells of an established tumor are in G0/G1 phase. Longitudinal real-time FUCCI imaging demonstrated that cytotoxic agents killed only proliferating cancer cells at the surface and, in contrast, and had little effect on the quiescent cancer cells. Resistant quiescent cancer cells restarted cycling after the cessation of chemotherapy. Thus cytotoxic chemotherapy which targets cells in S/G2/M, is mostly ineffective on solid tumors, but causes toxic side effects on tissues with high fractions of cycling cells, such as hair follicles, bone marrow and the intestinal lining. We have termed this phenomenon tumor intrinsic chemoresistance (TIC). We previously demonstrated that tumor-targeting Salmonella typhimurium A1-R (S. typhimurium A1-R) decoyed quiescent cancer cells in tumors to cycle from G0/G1 to S/G2/M demonstrated by FUCCI imaging. We have also previously shown that when cancer cells were treated with recombinant methioninase (rMETase), the cancer cells were selectively trapped in S/G2, shown by cell sorting as well as by FUCCI. In the present study, we show that sequential treatment of FUCCI-expressing stomach cancer MKN45 in vivo with S. typhimurium A1-R to decoy quiescent cancer cells to cycle, with subsequent rMETase to selectively trap the decoyed cancer cells in S/G2 phase, followed by cisplatinum (CDDP) or paclitaxel (PTX) chemotherapy to kill the decoyed and trapped cancer cells completely prevented or regressed tumor growth. These results demonstrate the effectiveness of the praradigm of "decoy, trap and shoot" chemotherapy.
['Yano|Shuya|S|', 'Takehara|Kiyoto|K|', 'Zhao|Ming|M|', 'Tan|Yuying|Y|', 'Han|Qinghong|Q|', 'Li|Shukuan|S|', 'Bouvet|Michael|M|', 'Fujiwara|Toshiyoshi|T|', 'Hoffman|Robert M|RM|']
D000818:Animals D000970:Antineoplastic Agents D013437:Carbon-Sulfur Lyases D002453:Cell Cycle D002945:Cisplatin D019008:Drug Resistance, Neoplasm D005453:Fluorescence D016195:G2 Phase D006367:HeLa Cells D006801:Humans D021621:Imaging, Three-Dimensional D008819:Mice, Nude D009369:Neoplasms D017239:Paclitaxel D011994:Recombinant Proteins D016196:S Phase D012486:Salmonella typhimurium D054875:Ubiquitination
cell-cycle decoy Salmonella typhimurium A1-R trap methioninase FUCCI cancer stomach cancer cisplatinum paclitaxel nude mice