title: Capilliposide from Lysimachia capillipes inhibits AKT activation and restores gefitinib sensitivity in human non-small cell lung cancer cells with acquired gefitinib resistance.
abstract: Most gefitinib-treated patients with non-small cell lung cancer (NSCLC) would eventually develop resistance. Lysimachia capillipes (LC) capilliposide extracts from LC Hemsl. show both in vitro and in vivo anti-cancer effects. In this study we investigated whether LC capilliposide in combination with gefitinib could overcome the resistance of NSCLC cells to gefitinib and identified the signaling pathways involved. Treatment with LC capilliposide alone inhibited the growth of a panel of NSCLC cell lines (PC-9, H460, H1975, H1299 and PC-9-GR) sensitive or resistant to gefitinib with IC50values in the range of μg/mL. In the gefitinib-resistant PC-9-GR cells (which have a T790M EGFR mutation), LC capilliposide (at the IC30, i.e.1.2 μg/mL) markedly enhanced the inhibitory effects of gefitinib with its IC50 value being decreased from 6.80±1.00 to 0.77±0.12 μmol/L. By using the median effect analysis we showed that combination treatment of LC capilliposide and gefitinib could restore gefitinib sensitivity in PC-9-GR cells. Furthermore, LC capilliposide (1.2 μg/mL) significantly increased the apoptotic responses to gefitinib (0.77 μmol/L) in PC-9-GR cells, but did not affect gefitinib-induced G0/G1arrest. Moreover, LC capilliposide (1.2 μg/mL) in combination with gefitinib (0.77, 1.0 μmol/L) markedly decreased the phosphorylation of the EGFR downstream signaling molecule AKT, which neither LC capilliposide nor gefitinib alone affected. In PC-9-GR cells with siRNA knockdown of AKT, addition of LC capilliposide was unable to increase gefitinib sensitivity. In a PC-9-GR xenograft mouse model, combination treatment with LC capilliposide (15 mg·kg-1·d-1, ip) and gefitinib (50 mg·kg-1·d-1, ip) dramatically enhanced tumor growth suppression (with a TGI of 109.3%), compared with TGIs of 22.6% and 56.6%, respectively, in mice were treated with LC capilliposide or gefitinib alone. LC capilliposide can restore the cells' sensitivity to gefitinib through modulation of pAKT levels, suggesting that a combination of LC capilliposide and gefitinib may be a promising therapeutic strategy to overcome gefitinib resistance in NSCLCs with a T790M mutation.
authors.affiliation: College of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, China.|Department of Oncology, Hangzhou First People's Hospital, Nanjing Medical University, Hangzhou 310006, China.
authors.forename: Shi-Rong
authors.initials: SR
authors.lastname: Zhang
authors.affiliation: College of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, China.|Department of Oncology, Hangzhou First People's Hospital, Nanjing Medical University, Hangzhou 310006, China.
authors.forename: Ya-Si
authors.initials: YS
authors.lastname: Xu
authors.affiliation: Department of Oncology, Hangzhou First People's Hospital, Nanjing Medical University, Hangzhou 310006, China.
authors.forename: Er
authors.initials: E
authors.lastname: Jin
authors.affiliation: Department of Oncology, Hangzhou First People's Hospital, Nanjing Medical University, Hangzhou 310006, China.
authors.forename: Lu-Cheng
authors.initials: LC
authors.lastname: Zhu
authors.affiliation: Department of Oncology, Hangzhou First People's Hospital, Nanjing Medical University, Hangzhou 310006, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Xia
authors.affiliation: Department of Pathology and Laboratory Medicine, University of California at Los Angeles, Los Angeles CA, 90095, USA.
authors.forename: Xu-Feng
authors.initials: XF
authors.lastname: Chen
authors.affiliation: College of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, China.
authors.forename: Fan-Zhu
authors.initials: FZ
authors.lastname: Li
authors.affiliation: Department of Oncology, Hangzhou First People's Hospital, Nanjing Medical University, Hangzhou 310006, China.
authors.forename: Sheng-Lin
authors.initials: SL
authors.lastname: Ma
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D017209:Apoptosis / Q000187:drug effects; D002289:Carcinoma, Non-Small-Cell Lung / Q000201:enzymology* / Q000473:pathology; D059447:Cell Cycle Checkpoints / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D019008:Drug Resistance, Neoplasm / Q000187:drug effects; D005260:Female; D000077156:Gefitinib; D006801:Humans; D008175:Lung Neoplasms / Q000201:enzymology* / Q000473:pathology; D051379:Mice; D010766:Phosphorylation / Q000187:drug effects; D029623:Primulaceae / Q000737:chemistry*; D047428:Protein Kinase Inhibitors / Q000494:pharmacology / Q000627:therapeutic use; D051057:Proto-Oncogene Proteins c-akt / Q000037:antagonists & inhibitors* / Q000378:metabolism; D011799:Quinazolines / Q000494:pharmacology / Q000627:therapeutic use*; D034741:RNA, Small Interfering / Q000494:pharmacology; D012503:Saponins / Q000494:pharmacology / Q000627:therapeutic use*; D014315:Triterpenes / Q000494:pharmacology / Q000627:therapeutic use*; D023041:Xenograft Model Antitumor Assays
chemical_list: D000970:Antineoplastic Agents; C000621632:LC capilliposide; D047428:Protein Kinase Inhibitors; D011799:Quinazolines; D034741:RNA, Small Interfering; D012503:Saponins; D014315:Triterpenes; D051057:Proto-Oncogene Proteins c-akt; D000077156:Gefitinib