title: γ-Sitosterol from Acacia nilotica L. induces G2/M cell cycle arrest and apoptosis through c-Myc suppression in MCF-7 and A549 cells.
abstract: BACKGROUND
  Acacia nilotica is widely distributed in Asia. In India, it occupies an important place in the indigenous system of medicine against anti-inflammatory, antioxidant, cancers, and/or tumors.
  
  
  OBJECTIVE
  The purpose of this study is to investigate the inhibitory effect of Acacia nilotica leaves extract and γ-Sitosterol on cell proliferation, the apoptotic effect and cell cycle arrest in breast and lung cancer cells.
  
  
  METHODS
  GC-MS and HPLC were used to determine the chemical constituents of this extract and γ-Sitosterol respectively. Human MCF-7 and A549 cell lines were treated with Acacia nilotica extract and γ-Sitosterol. Cell viability was determined by MTT assay. Cell proliferation was determined by BrdU incorporation assay. Apoptosis was detected by cell morphologic observation through AO/EtBr staining, cell cycle analysis, and immunoblot analysis on the expression of protein associated with cell cycle arrest.
  
  
  RESULTS
  Experimental results of bioactive compound analysis indicate that γ-Sitosterol, bioactive ingredients of Acacia nilotica extract. The IC(50) value of extract on MCF-7 and A549 cancer cells was 493.3±15.2 and 696.6±11.5 μg/ml, respectively. Acacia nilotica extract and γ-Sitosterol were inhibited the cell proliferation by 54.34±1.8 and 42.18±3.9% for MCF-7 and 58.26±1.5 and 44.36±3.05% for A549 cells. The percentage of apoptotic cells observed in the MCF-7 and A549 cell lines were increased to 42.46 and 36.8% of extract; 46.68 and 43.24% for γ-Sitosterol respectively. Flow cytometric analysis results demonstrate that cells were arrested at the G2/M phase and decrease the c-Myc expression.
  
  
  CONCLUSIONS
  This study demonstrates in vitro results, which support the ethnomedical use of γ-Sitosterol against cancer. Experimental results of this study suggest that γ-Sitosterol exerts potential anticancer activity through the growth inhibition, cell cycle arrest and the apoptosis on cancer cells.
authors.affiliation: Department of Zoology, School of Life Sciences, Bharathiar University, Coimbatore 641046, TN, India.
authors.forename: Shenbagamoorthy
authors.initials: S
authors.lastname: Sundarraj
authors.forename: Ramar
authors.initials: R
authors.lastname: Thangam
authors.forename: Vellingiri
authors.initials: V
authors.lastname: Sreevani
authors.forename: Krishnasamy
authors.initials: K
authors.lastname: Kaveri
authors.forename: Palani
authors.initials: P
authors.lastname: Gunasekaran
authors.forename: Shanmugam
authors.initials: S
authors.lastname: Achiraman
authors.forename: Soundarapandian
authors.initials: S
authors.lastname: Kannan
mesh_terms: D000045:Acacia; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D002453:Cell Cycle / Q000187:drug effects; D059447:Cell Cycle Checkpoints / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D019926:Cyclin B / Q000378:metabolism; D019927:Cyclin E / Q000378:metabolism; D006801:Humans; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D018515:Plant Leaves; D016271:Proto-Oncogene Proteins c-myc / Q000378:metabolism; D012855:Sitosterols / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D019926:Cyclin B; D019927:Cyclin E; D010936:Plant Extracts; D016271:Proto-Oncogene Proteins c-myc; D012855:Sitosterols; C025473:gamma-sitosterol