title: Curcumin sensitizes human colorectal cancer to capecitabine by modulation of cyclin D1, COX-2, MMP-9, VEGF and CXCR4 expression in an orthotopic mouse model.
abstract: Because of the poor prognosis and the development of resistance against chemotherapeutic drugs, the current treatment for advanced metastatic colorectal cancer (CRC) is ineffective. Whether curcumin (a component of turmeric) can potentiate the effect of capecitabine against growth and metastasis of CRC was investigated. The effect of curcumin on proliferation of CRC cell lines was examined by mitochondrial dye-uptake assay, apoptosis by esterase staining, nuclear factor-kappaB (NF-kappaB) by electrophoretic mobility shift assay and gene expression by Western blot analysis. The effect of curcumin on the growth and metastasis of CRC was also examined in orthotopically implanted tumors in nude mice. In vitro, curcumin inhibited the proliferation of human CRC cell lines, potentiated capecitabine-induced apoptosis, inhibited NF-kappaB activation and suppressed NF-kappaB-regulated gene products. In nude mice, the combination of curcumin and capecitabine was found to be more effective than either agent alone in reducing tumor volume (p = 0.001 vs. control; p = 0.031 vs. capecitabine alone), Ki-67 proliferation index (p = 0.001 vs. control) and microvessel density marker CD31. The combination treatment was also highly effective in suppressing ascites and distant metastasis to the liver, intestines, lungs, rectum and spleen. This effect was accompanied by suppressed expression of activated NF-kappaB and NF-kappaB-regulated gene products (cyclin D1,c-myc, bcl-2, bcl-xL, cIAP-1, COX-2, ICAM-1, MMP-9, CXCR4 and VEGF). Overall, our results suggest that curcumin sensitizes CRC to the antitumor and antimetastatic effects of capecitabine by suppressing NF-kappaB cell signaling pathway.
authors.affiliation: Department of Experimental Therapeutics, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA.
authors.forename: Ajaikumar B
authors.initials: AB
authors.lastname: Kunnumakkara
authors.forename: Parmeswaran
authors.initials: P
authors.lastname: Diagaradjane
authors.forename: Preetha
authors.initials: P
authors.lastname: Anand
authors.forename: Kuzhuvelil B
authors.initials: KB
authors.lastname: Harikumar
authors.forename: Harikumar B
authors.initials: HB
authors.lastname: Kuzhuvelil
authors.forename: Amit
authors.initials: A
authors.lastname: Deorukhkar
authors.forename: Juri
authors.initials: J
authors.lastname: Gelovani
authors.forename: Sushovan
authors.initials: S
authors.lastname: Guha
authors.forename: Sunil
authors.initials: S
authors.lastname: Krishnan
authors.forename: Bharat B
authors.initials: BB
authors.lastname: Aggarwal
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D000069287:Capecitabine; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D003474:Curcumin / Q000494:pharmacology*; D019938:Cyclin D1 / Q000235:genetics*; D051546:Cyclooxygenase 2 / Q000235:genetics*; D003841:Deoxycytidine / Q000031:analogs & derivatives* / Q000494:pharmacology; D004357:Drug Synergism; D005472:Fluorouracil / Q000031:analogs & derivatives* / Q000494:pharmacology; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D006801:Humans; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000235:genetics*; D051379:Mice; D016328:NF-kappa B / Q000037:antagonists & inhibitors; D009362:Neoplasm Metastasis / Q000517:prevention & control; D019718:Receptors, CXCR4; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics*
chemical_list: D000970:Antineoplastic Agents; C527276:CXCR4 protein, human; D016328:NF-kappa B; D019718:Receptors, CXCR4; D042461:Vascular Endothelial Growth Factor A; D003841:Deoxycytidine; D019938:Cyclin D1; D000069287:Capecitabine; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D020780:Matrix Metalloproteinase 9; D003474:Curcumin; D005472:Fluorouracil