title: Combined inhibitory effects of curcumin and phenethyl isothiocyanate on the growth of human PC-3 prostate xenografts in immunodeficient mice.
abstract: Earlier studies using prostate cancer cells in culture showed that phenethyl isothiocyanate (PEITC) and curcumin have significant chemopreventive and possibly chemotherapeutic effects. However, their in vivo effects are still lacking. Hence, this study was undertaken to determine the possible in vivo efficacy of prostate cancer-prevention as well as cancer-therapeutic treatment by PEITC and curcumin alone or in combination. We evaluated the effects on tumor growth in vivo, using NCr immunodeficient (nu/nu) mice bearing s.c. xenografts of PC-3 human prostate cancer cells. Molecular biomarkers representing proliferation and apoptosis were determined. Continued i.p. injection of curcumin or PEITC (6 and 5 mumol; thrice a week for 28 days), beginning a day before tumor implantation significantly retarded the growth of PC-3 xenografts. Combination of i.p. administration of PEITC (2.5 mumol) and curcumin (3 mumol) showed stronger growth-inhibitory effects. Next, we evaluated the cancer-therapeutic potential of curcumin and PEITC in mice with well-established tumors, and the results showed that PEITC or curcumin alone had little effect, whereas combination of curcumin and PEITC significantly reduced the growth of PC-3 xenografts. Immunohistochemistry staining and Western blot analysis revealed that the inhibition of Akt and nuclear factor-kappaB signaling pathways could contribute to the inhibition of cell proliferation and induction of apoptosis. Taken together, our results show that PEITC and curcumin alone or in combination possess significant cancer-preventive activities in the PC-3 prostate tumor xenografts. Furthermore, we found that combination of PEITC and curcumin could be effective in the cancer-therapeutic treatment of prostate cancers.
authors.affiliation: Center for Cancer Prevention Research, Department of Pharmaceutics, Ernest Mario School of Pharmacy, Rutgers-The State University of New Jersey, 160 Freilinghuysen Road, Piscataway, NJ 08854, USA.
authors.forename: Tin Oo
authors.initials: TO
authors.lastname: Khor
authors.forename: Young-Sam
authors.initials: YS
authors.lastname: Keum
authors.forename: Wen
authors.initials: W
authors.lastname: Lin
authors.forename: Jung-Hwan
authors.initials: JH
authors.lastname: Kim
authors.forename: Rong
authors.initials: R
authors.lastname: Hu
authors.forename: Guoxiang
authors.initials: G
authors.lastname: Shen
authors.forename: Changjiang
authors.initials: C
authors.lastname: Xu
authors.forename: Avanthika
authors.initials: A
authors.lastname: Gopalakrishnan
authors.forename: Bandaru
authors.initials: B
authors.lastname: Reddy
authors.forename: Xi
authors.initials: X
authors.lastname: Zheng
authors.forename: Allan H
authors.initials: AH
authors.lastname: Conney
authors.forename: Ah-Ng Tony
authors.initials: AN
authors.lastname: Kong
mesh_terms: D000818:Animals; D016588:Anticarcinogenic Agents / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D014408:Biomarkers, Tumor / Q000032:analysis; D049109:Cell Proliferation / Q000187:drug effects; D003474:Curcumin / Q000494:pharmacology*; D016867:Immunocompromised Host; D007150:Immunohistochemistry; D007263:Infusions, Parenteral; D017879:Isothiocyanates / Q000494:pharmacology*; D008297:Male; D051379:Mice; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000276:immunology / Q000517:prevention & control*; D014183:Transplantation, Heterologous
chemical_list: D016588:Anticarcinogenic Agents; D000970:Antineoplastic Agents; D014408:Biomarkers, Tumor; D017879:Isothiocyanates; C058305:phenethyl isothiocyanate; D003474:Curcumin