BACKGROUND: Uterine leiomyosarcoma (LMS) has an unfavorable response to standard chemotherapeutic regimens. Two natural occurring compounds, curcumin and epigallocatechin gallate (EGCG), are reported to have anti-cancer activity. We previously reported that curcumin reduced uterine LMS cell proliferation by targeting the AKT-mTOR pathway. However, challenges remain in overcoming curcumin's low bioavailability. METHODS: The human LMS cell line SKN was used. The effect of EGCG, curcumin or their combination on cell growth was detected by MTS assay. Their effect on AKT, mTOR, and S6 was detected by Western blotting. The induction of apoptosis was determined by Western blotting using cleaved-PARP specific antibody, caspase-3 activity and TUNEL assay. Intracellular curcumin level was determined by a spectrophotometric method. Antibody against EGCG cell surface receptor, 67-kDa laminin receptor (67LR), was used to investigate the role of the receptor in curcumin's increased potency by EGCG. RESULTS: In this study, we showed that the combination of EGCG and curcumin significantly reduced SKN cell proliferation more than either drug alone. The combination inhibited AKT, mTOR, and S6 phosphorylation, and induced apoptosis at a much lower curcumin concentration than previously reported. EGCG enhanced the incorporation of curcumin. 67LR antibody partially rescued cell proliferation suppression by the combination treatment, but was not involved in the EGCG-enhanced intracellular incorporation of curcumin. CONCLUSIONS: EGCG significantly lowered the concentration of curcumin required to inhibit the AKT-mTOR pathway, reduce cell proliferation and induce apoptosis in uterine LMS cells by enhancing intracellular incorporation of curcumin, but the process was independent of 67LR.
BACKGROUND: Uterine leiomyosarcoma (LMS) has an unfavorable response to standard chemotherapeutic regimens. Two natural occurring compounds, curcumin and epigallocatechin gallate (EGCG), are reported to have anti-cancer activity. We previously reported that curcumin reduced uterine LMS cell proliferation by targeting the AKT-mTOR pathway. However, challenges remain in overcoming curcumin's low bioavailability. METHODS: The human LMS cell line SKN was used. The effect of EGCG, curcumin or their combination on cell growth was detected by MTS assay. Their effect on AKT, mTOR, and S6 was detected by Western blotting. The induction of apoptosis was determined by Western blotting using cleaved-PARP specific antibody, caspase-3 activity and TUNEL assay. Intracellular curcumin level was determined by a spectrophotometric method. Antibody against EGCG cell surface receptor, 67-kDa laminin receptor (67LR), was used to investigate the role of the receptor in curcumin's increased potency by EGCG. RESULTS: In this study, we showed that the combination of EGCG and curcumin significantly reduced SKN cell proliferation more than either drug alone. The combination inhibited AKT, mTOR, and S6 phosphorylation, and induced apoptosis at a much lower curcumin concentration than previously reported. EGCG enhanced the incorporation of curcumin. 67LR antibody partially rescued cell proliferation suppression by the combination treatment, but was not involved in the EGCG-enhanced intracellular incorporation of curcumin. CONCLUSIONS:EGCG significantly lowered the concentration of curcumin required to inhibit the AKT-mTOR pathway, reduce cell proliferation and induce apoptosis in uterine LMS cells by enhancing intracellular incorporation of curcumin, but the process was independent of 67LR.
Authors: G A Omura; J A Blessing; F Major; S Lifshitz; C E Ehrlich; C Mangan; J Beecham; R Park; S Silverberg Journal: J Clin Oncol Date: 1985-09 Impact factor: 44.544
Authors: Keith I Block; Charlotte Gyllenhaal; Leroy Lowe; Amedeo Amedei; A R M Ruhul Amin; Amr Amin; Katia Aquilano; Jack Arbiser; Alexandra Arreola; Alla Arzumanyan; S Salman Ashraf; Asfar S Azmi; Fabian Benencia; Dipita Bhakta; Alan Bilsland; Anupam Bishayee; Stacy W Blain; Penny B Block; Chandra S Boosani; Thomas E Carey; Amancio Carnero; Marianeve Carotenuto; Stephanie C Casey; Mrinmay Chakrabarti; Rupesh Chaturvedi; Georgia Zhuo Chen; Helen Chen; Sophie Chen; Yi Charlie Chen; Beom K Choi; Maria Rosa Ciriolo; Helen M Coley; Andrew R Collins; Marisa Connell; Sarah Crawford; Colleen S Curran; Charlotta Dabrosin; Giovanna Damia; Santanu Dasgupta; Ralph J DeBerardinis; William K Decker; Punita Dhawan; Anna Mae E Diehl; Jin-Tang Dong; Q Ping Dou; Janice E Drew; Eyad Elkord; Bassel El-Rayes; Mark A Feitelson; Dean W Felsher; Lynnette R Ferguson; Carmela Fimognari; Gary L Firestone; Christian Frezza; Hiromasa Fujii; Mark M Fuster; Daniele Generali; Alexandros G Georgakilas; Frank Gieseler; Michael Gilbertson; Michelle F Green; Brendan Grue; Gunjan Guha; Dorota Halicka; William G Helferich; Petr Heneberg; Patricia Hentosh; Matthew D Hirschey; Lorne J Hofseth; Randall F Holcombe; Kanya Honoki; Hsue-Yin Hsu; Gloria S Huang; Lasse D Jensen; Wen G Jiang; Lee W Jones; Phillip A Karpowicz; W Nicol Keith; Sid P Kerkar; Gazala N Khan; Mahin Khatami; Young H Ko; Omer Kucuk; Rob J Kulathinal; Nagi B Kumar; Byoung S Kwon; Anne Le; Michael A Lea; Ho-Young Lee; Terry Lichtor; Liang-Tzung Lin; Jason W Locasale; Bal L Lokeshwar; Valter D Longo; Costas A Lyssiotis; Karen L MacKenzie; Meenakshi Malhotra; Maria Marino; Maria L Martinez-Chantar; Ander Matheu; Christopher Maxwell; Eoin McDonnell; Alan K Meeker; Mahya Mehrmohamadi; Kapil Mehta; Gregory A Michelotti; Ramzi M Mohammad; Sulma I Mohammed; D James Morre; Vinayak Muralidhar; Irfana Muqbil; Michael P Murphy; Ganji Purnachandra Nagaraju; Rita Nahta; Elena Niccolai; Somaira Nowsheen; Carolina Panis; Francesco Pantano; Virginia R Parslow; Graham Pawelec; Peter L Pedersen; Brad Poore; Deepak Poudyal; Satya Prakash; Mark Prince; Lizzia Raffaghello; Jeffrey C Rathmell; W Kimryn Rathmell; Swapan K Ray; Jörg Reichrath; Sarallah Rezazadeh; Domenico Ribatti; Luigi Ricciardiello; R Brooks Robey; Francis Rodier; H P Vasantha Rupasinghe; Gian Luigi Russo; Elizabeth P Ryan; Abbas K Samadi; Isidro Sanchez-Garcia; Andrew J Sanders; Daniele Santini; Malancha Sarkar; Tetsuro Sasada; Neeraj K Saxena; Rodney E Shackelford; H M C Shantha Kumara; Dipali Sharma; Dong M Shin; David Sidransky; Markus David Siegelin; Emanuela Signori; Neetu Singh; Sharanya Sivanand; Daniel Sliva; Carl Smythe; Carmela Spagnuolo; Diana M Stafforini; John Stagg; Pochi R Subbarayan; Tabetha Sundin; Wamidh H Talib; Sarah K Thompson; Phuoc T Tran; Hendrik Ungefroren; Matthew G Vander Heiden; Vasundara Venkateswaran; Dass S Vinay; Panagiotis J Vlachostergios; Zongwei Wang; Kathryn E Wellen; Richard L Whelan; Eddy S Yang; Huanjie Yang; Xujuan Yang; Paul Yaswen; Clement Yedjou; Xin Yin; Jiyue Zhu; Massimo Zollo Journal: Semin Cancer Biol Date: 2015-12 Impact factor: 15.707