BioCentury
ARTICLE | Distillery Therapeutics

Cancer

October 3, 2017 7:40 PM UTC

Patient sample, cell culture and mouse studies suggest antibiotics could help treat Gemzar gemcitabine-resistant colorectal and pancreatic cancers. In 113 tumor samples from pancreatic ductal adenocarcinoma (PDAC) patients, bacterial DNA -- primarily from the Gammaproteobacteria class -- was detected in 86 samples (76%), whereas in 20 healthy pancreas samples from organ donors, bacterial DNA was detected in 3 samples (15%). In a human colorectal cancer line, co-culture with E. coli, Klebsiella pneumoniae or one of 10 other bacterial species expressing cytidine/deoxycytidine deaminase (CDD), or with bacteria isolated from the tumors of 14 PDAC patients, increased resistance to gemcitabine compared with co-culture with non-CDD-expressing bacteria or no co-culture. In a mouse model of colon cancer with intratumoral E. coli infection, Gemzar plus the antibiotic ciprofloxacin decreased tumor growth compared with gemcitabine alone. Next steps include exploring the effect of intratumoral bacteria on resistance to other therapeutic agents in undisclosed tumor types...