title: Combination of tolfenamic acid and curcumin induces colon cancer cell growth inhibition through modulating specific transcription factors and reactive oxygen species.
abstract: Curcumin (Cur) has been extensively studied in several types of malignancies including colorectal cancer (CRC); however its clinical application is greatly affected by low bioavailability. Several strategies to improve the therapeutic response of Cur are being pursued, including its combination with small molecules and drugs. We investigated the therapeutic efficacy of Cur in combination with the small molecule tolfenamic acid (TA) in CRC cell lines. TA has been shown to inhibit the growth of human cancer cells in vitro and in vivo, via targeting the transcription factor specificity protein1 (Sp1) and suppressing survivin expression. CRC cell lines HCT116 and HT29 were treated with TA and/or Cur and cell viability was measured 24-72 hours post-treatment. While both agents caused a steady reduction in cell viability, following a clear dose/ time-dependent response, the combination of TA+Cur showed higher growth inhibition when compared to either single agent. Effects on apoptosis were determined using flow cytometry (JC-1 staining to measure mitochondrial membrane potential), Western blot analysis (c-PARP expression) and caspase 3/7 activity. Reactive oxygen species (ROS) levels were measured by flow cytometry and the translocation of NF-kB into the nucleus was determined using immunofluorescence. Results showed that apoptotic markers and ROS activity were significantly upregulated following combination treatment, when compared to the individual agents. This was accompanied by decreased expression of Sp1, survivin and NF-kB translocation. The combination of TA+Cur was more effective in HCT116 cells than HT29 cells. These results demonstrate that TA may enhance the anti-proliferative efficacy of Cur in CRC cells.
authors.affiliation: Institute for Cancer Research, University of North Texas Health Science Center, Fort Worth, TX 76107, USA.|Texas College of Osteopathic Medicine, University of North Texas Health Science Center, Fort Worth, TX 76107, USA.
authors.forename: Umesh T
authors.initials: UT
authors.lastname: Sankpal
authors.affiliation: Department of Hematology Medical Oncology, Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA.
authors.forename: Ganji Purnachandra
authors.initials: GP
authors.lastname: Nagaraju
authors.affiliation: Texas College of Osteopathic Medicine, University of North Texas Health Science Center, Fort Worth, TX 76107, USA.
authors.forename: Sriharika R
authors.initials: SR
authors.lastname: Gottipolu
authors.affiliation: Texas College of Osteopathic Medicine, University of North Texas Health Science Center, Fort Worth, TX 76107, USA.
authors.forename: Myrna
authors.initials: M
authors.lastname: Hurtado
authors.affiliation: Institute for Cancer Research, University of North Texas Health Science Center, Fort Worth, TX 76107, USA.|JPS Center for Cancer Care, Fort Worth, TX 76104, USA.
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Jordan
authors.affiliation: Preclinical Services, University of North Texas Health Science Center, Fort Worth, TX 76107, USA.|College of Pharmacy, University of North Texas Health Science Center, Fort Worth, TX 76107, USA.
authors.forename: Jerry W
authors.initials: JW
authors.lastname: Simecka
authors.affiliation: Department of Hematology Medical Oncology, Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA.
authors.forename: Mamoru
authors.initials: M
authors.lastname: Shoji
authors.affiliation: Department of Hematology Medical Oncology, Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA.
authors.forename: Bassel
authors.initials: B
authors.lastname: El-Rayes
authors.affiliation: Institute for Cancer Research, University of North Texas Health Science Center, Fort Worth, TX 76107, USA.|Texas College of Osteopathic Medicine, University of North Texas Health Science Center, Fort Worth, TX 76107, USA.|Preclinical Services, University of North Texas Health Science Center, Fort Worth, TX 76107, USA.
authors.forename: Riyaz
authors.initials: R
authors.lastname: Basha
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000187:drug effects; D000970:Antineoplastic Agents / Q000494:pharmacology*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D053148:Caspase 3 / Q000378:metabolism; D053179:Caspase 7 / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003110:Colonic Neoplasms / Q000188:drug therapy*; D003474:Curcumin / Q000494:pharmacology*; D005434:Flow Cytometry; D045325:HCT116 Cells; D019073:HT29 Cells; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins / Q000096:biosynthesis*; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D016328:NF-kappa B / Q000378:metabolism; D000071137:Poly (ADP-Ribose) Polymerase-1 / Q000096:biosynthesis; D017382:Reactive Oxygen Species / Q000378:metabolism*; D016329:Sp1 Transcription Factor / Q000096:biosynthesis*; D000077022:Survivin; D062367:ortho-Aminobenzoates / Q000494:pharmacology*
chemical_list: D000970:Antineoplastic Agents; C107489:BIRC5 protein, human; D051034:Inhibitor of Apoptosis Proteins; D016328:NF-kappa B; D017382:Reactive Oxygen Species; D016329:Sp1 Transcription Factor; C108209:SP1 protein, human; D000077022:Survivin; D062367:ortho-Aminobenzoates; C009500:tolfenamic acid; C499320:PARP1 protein, human; D000071137:Poly (ADP-Ribose) Polymerase-1; D053148:Caspase 3; D053179:Caspase 7; D003474:Curcumin
keywords: NF-kB; Sp1; colon cancer; curcumin; tolfenamic acid