Ursolic Acid Inhibits Growth and Metastasis of Human Colorectal Cancer in an Orthotopic Nude Mouse Model by Targeting Multiple Cell Signaling Pathways: Chemosensitization with Capecitabine

• Published in: Clinical cancer research Vol. 18; no. 18; pp. 4942 - 4953
• Main Authors: PRASAD, Sahdeo, YADAV, Vivek R, GUHA, Sushovan, AGGARWAL, Bharat B, SUNG, Bokyung, REUTER, Simone, KANNAPPAN, Ramaswamy, DEORUKHKAR, Amit, DIAGARADJANE, Parmeswaran, WEI, Caimiao, BALADANDAYUTHAPANI, Veerabhadran, KRISHNAN, Sunil
• Format: Journal Article
• Language: English
• Published: Philadelphia, PA American Association for Cancer Research 15.09.2012
• Subjects: Animals; Antimetabolites, Antineoplastic - administration & dosage; Antimetabolites, Antineoplastic - pharmacology; Antimetabolites, Antineoplastic - toxicity; Antineoplastic agents; Antineoplastic Combined Chemotherapy Protocols - administration & dosage; Antineoplastic Combined Chemotherapy Protocols - therapeutic use; Apoptosis - drug effects; beta Catenin - metabolism; Biological and medical sciences; Capecitabine; Cell Line, Tumor; Cell Proliferation - drug effects; Cell Survival - drug effects; Colorectal Neoplasms - drug therapy; Colorectal Neoplasms - metabolism; Colorectal Neoplasms - pathology; Deoxycytidine - administration & dosage; Deoxycytidine - analogs & derivatives; Deoxycytidine - pharmacology; Deoxycytidine - toxicity; Disease Models, Animal; Drug Resistance, Neoplasm - drug effects; Drug Synergism; ErbB Receptors - metabolism; Fluorouracil - administration & dosage; Fluorouracil - analogs & derivatives; Fluorouracil - pharmacology; Fluorouracil - toxicity; Gastroenterology. Liver. Pancreas. Abdomen; Humans; Ki-67 Antigen - metabolism; Male; Medical sciences; Mice; Mice, Nude; Neoplasm Metastasis - drug therapy; NF-kappa B - antagonists & inhibitors; NF-kappa B - metabolism; Pharmacology. Drug treatments; Platelet Endothelial Cell Adhesion Molecule-1 - metabolism; Signal Transduction - drug effects; STAT3 Transcription Factor - metabolism; Stomach. Duodenum. Small intestine. Colon. Rectum. Anus; Triterpenes - administration & dosage; Triterpenes - therapeutic use; Tumor Suppressor Proteins - metabolism; Tumors; Ursolic Acid; Xenograft Model Antitumor Assays; Antineoplastic agent; Animal model; Rectal disease; Targeting; Capecitabine; Growth; Colorectal cancer; Metastasis; Cell signaling; Signal transduction; Target; Signaling pathway; Intestinal disease; Pyrimidine nucleoside; Human; Orthotopic; Fluoropyrimidine derivatives; Rodentia; Malignant tumor; Prodrug; Colonic disease; Vertebrata; Mammalia; Mouse; Chemosensitivity; Digestive diseases; Inhibitor; Cancer
• ISSN: 1078-0432; 1557-3265
• DOI: 10.1158/1078-0432.CCR-11-2805

Development of chemoresistance, poor prognosis, and metastasis often renders the current treatments for colorectal cancer (CRC) ineffective. Whether ursolic acid, a component of numerous medicinal plants, either alone or in combination with capecitabine, can inhibit the growth and metastasis of human CRC was investigated. The effect of ursolic acid on proliferation of CRC cell lines was examined by mitochondrial dye uptake assay, apoptosis by esterase staining, NF-κB activation by DNA-binding assay, and protein expression by Western blot. The effect of ursolic acid on the growth and chemosensitization was also examined in orthotopically implanted CRC in nude mice. We found that ursolic acid inhibited the proliferation of different colon cancer cell lines. This is correlated with inhibition of constitutive NF-κB activation and downregulation of cell survival (Bcl-xL, Bcl-2, cFLIP, and survivin), proliferative (cyclin D1), and metastatic (MMP-9, VEGF, and ICAM-1) proteins. When examined in an orthotopic nude mouse model, ursolic acid significantly inhibited tumor volume, ascites formation, and distant organ metastasis, and this effect was enhanced with capecitabine. Immunohistochemistry of tumor tissue indicated that ursolic acid downregulated biomarkers of proliferation (Ki-67) and microvessel density (CD31). This effect was accompanied by suppression of NF-κB, STAT3, and β-catenin. In addition, ursolic acid suppressed EGF receptor (EGFR) and induced p53 and p21 expression. We also observed bioavailability of ursolic acid in the serum and tissue of animals. Overall, our results show that ursolic acid can inhibit the growth and metastasis of CRC and further enhance the therapeutic effects of capecitabine through the suppression of multiple biomarkers linked to inflammation, proliferation, invasion, angiogenesis, and metastasis.