%0 Journal Article %A KAMILA ŚRODA-POMIANEK %A OLGA WESOŁOWSKA %A BERENIKA SZCZĘŚNIAK-SIĘGA %A BARTOSZ PUŁA %A PIOTR DZIĘGIEL %A JADWIGA MANIEWSKA %A WIESŁAW MALINKA %A ANNA PALKO-ŁABUZ %A KRYSTYNA MICHALAK %T Effect of New Oxicam Derivatives on Efflux Pumps Overexpressed in Resistant a Human Colorectal Adenocarcinoma Cell Line %D 2015 %J Anticancer Research %P 2835-2840 %V 35 %N 5 %X Background: Oxicams are non-steroidal anti-inflammatory drugs (NSAIDs). Antitumor potential of NSAIDs has often been reported in literature. We studied antitumor activity of newly synthesized oxicam derivatives (PR17 and PR18) against doxorubicin-sensitive and resistant human colorectal adenocarcinoma cells (LoVo and LoVo/Dx). Materials and Methods: The cytotoxicity of oxicam derivatives alone and in combination with doxorubicin was assessed. Inhibition of P-glycoprotein (ABCB1) transport activity was monitored by flow cytometry. Expression of ABCB1 gene was analyzed by semi-quantitative reverse transcription PCR, while ABCB1 protein expression was assessed by western blotting. Results: Oxicam derivative PR18 was more cytotoxic to cancer cells than PR17. PR18 was observed to sensitize LoVo/Dx cells to doxorubicin and was identified as an effective multidrug resistance modulator. Additionally, ABCB1 expression was reduced in the presence of PR18. Conclusion: PR18 was identified as an effective modulator in LoVo/Dx resistant human colorectal adenocarcinoma cells which overexpressed ABCB1 efflux pump. %U https://ar.iiarjournals.org/content/anticanres/35/5/2835.full.pdf