title: Chinese herbal medicine Fuzheng Kang-Ai decoction sensitized the effect of gefitinib on inhibition of human lung cancer cells through inactivating PI3-K/Akt -mediated suppressing MUC1 expression.
abstract: BACKGROUND
  Chinese herbal medicine (CHM) Fuzheng Kang-Ai (FZKA for short) decoction has been used as adjuvant treatment strategies in lung cancer patients for decades. However, the molecular mechanism underlying the therapeutic potential especially in sensitizing the effect of EGFR-TKI gefitinib has not been well elucidated.
  
  
  METHODS
  Cell viability was detected by MTT assay. Cell cycle distribution was detected by flow cytometry. Western blot were used to examine phosphorylation and protein levels of Akt, p65, p50 and MUC1. The mRNA level of MUC1 was measured by qRT-PCR. Transient transfection experiments were used to overexpression of Akt, p65 and MUC1. Tumor xenograft and bioluminescent imaging experiments were carried out to confirm the in vitro findings.
  
  
  RESULTS
  Cell viability was inhibited by FZKA treatment and showed more significant when treated with FZKA and gefitinib in combine in lung cancer cells. FZKA induced the cell arrest at G0/G1 phase. Mechanistically, we showed that the phosphorylation of Akt, protein expressions of p65 and MUC1 were suppressed by FZKA and even more responses were observed in the FZKA and gefitinib combining. Overexpressed Akt overcame the effect of FZKA on p65 protein, and exogenously expressed p65 resisted the inhibitory effect of MUC1 protein expression by FZKA. On the contrary, while overexpressed MUC1 had no effect on p65 expression, it feedback increased phosphorylation of Akt, and more importantly, reversed the cell growth inhibition affected by FZKA. In line with the above, our results confirmed the synergistic effects of FZKA and gefitinib combination on tumor growth, the phosphorylation of Akt, and protein expression of p65 and MUC1 in vivo.
  
  
  CONCLUSIONS
  This study shows that FZKA decoction inhibits the growth of NSCLC cells through Akt-mediated inhibition of p65, followed by reducing the expression of MUC1. More importantly, there is a synergistic effect of FZKA decoction and gefitinib combination with greater suppression. The positive feedback regulatory loop of MUC1 to Akt signaling pathway further added the important role of MUC1 in mediating the overall responses of FZKA decoction in this process. The in vitro and in vivo study provides an additional and a novel mechanism by which the FZKA decoction enhances the growth inhibition of gefitinib in gefitinib-resistant NSCLC cells.
authors.affiliation: Laboratory of Tumor Molecular Biology and Targeted Therapies of TCM, China; Department of Medical Oncology, Guangdong Provincial Hospital of Chinese Medicine, The Second Clinical Medical Collage, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong Province 510120, China.
authors.forename: Longmei
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of Medical Oncology, Guangdong Provincial Hospital of Chinese Medicine, The Second Clinical Medical Collage, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong Province 510120, China.
authors.forename: SuMei
authors.initials: S
authors.lastname: Wang
authors.affiliation: Laboratory of Tumor Molecular Biology and Targeted Therapies of TCM, China.
authors.forename: Fang
authors.initials: F
authors.lastname: Zheng
authors.affiliation: Department of Medical Oncology, Guangdong Provincial Hospital of Chinese Medicine, The Second Clinical Medical Collage, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong Province 510120, China. Electronic address: wwanyin@126.com.
authors.forename: WanYin
authors.initials: W
authors.lastname: Wu
authors.affiliation: Laboratory of Tumor Molecular Biology and Targeted Therapies of TCM, China; Department of Medical Oncology, Guangdong Provincial Hospital of Chinese Medicine, The Second Clinical Medical Collage, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong Province 510120, China. Electronic address: hann2012@outlook.com.
authors.forename: Swei Sunny
authors.initials: SS
authors.lastname: Hann
mesh_terms: D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000494:pharmacology; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy* / Q000378:metabolism; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D004365:Drugs, Chinese Herbal / Q000008:administration & dosage / Q000494:pharmacology*; D000077156:Gefitinib; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D018396:Mucin-1 / Q000235:genetics / Q000378:metabolism*; D019869:Phosphatidylinositol 3-Kinases / Q000235:genetics / Q000378:metabolism*; D051057:Proto-Oncogene Proteins c-akt / Q000235:genetics / Q000378:metabolism*; D011799:Quinazolines / Q000008:administration & dosage / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; D004365:Drugs, Chinese Herbal; C060192:MUC1 protein, human; D018396:Mucin-1; D011799:Quinazolines; D012333:RNA, Messenger; C000606530:fuzheng kang'ai; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D000077156:Gefitinib
keywords: Akt; FZKA decoction; Gefitinib; MUC1; NSCLC cells; P65