title: Combination Therapy with AKT3 and PI3KCA siRNA Enhances the Antitumor Effect of Temozolomide and Carmustine in T98G Glioblastoma Multiforme Cells.
abstract: BACKGROUND
  Glioblastoma multiforme (GBM) is the most malignant and invasive human brain tumor, and it is characterized by a poor prognosis and short survival time. Current treatment strategies for GBM, using surgery, chemotherapy and/or radiotherapy, are ineffective. The PI3K/AKT/PTEN signaling pathway is frequently deregulated in this cancer, and it is connected with regulation of the cell cycle, apoptosis, and autophagy.
  
  
  OBJECTIVE
  The current study was undertaken to examine the effect of small interfering RNA (siRNA) targeting the AKT3 and PIK3CA genes on the susceptibility of T98G cells to temozolomide (TMZ) and carmustine (BCNU).
  
  
  METHODS
  T98G cells were transfected with AKT3 or PI3KCA siRNA. Transfection efficiency was assessed using flow cytometry and fluorescence microscopy. The influence of AKT3 and PI3KCA siRNA in combination with TMZ and BCNU on T98G cell viability, proliferation, apoptosis, and autophagy was evaluated as well. Alterations in messenger RNA (mRNA) expression of apoptosis-related and autophagy-related genes were analyzed using quantitative reverse transcription polymerase chain reaction (QRT-PCR).
  
  
  RESULTS
  Transfection of T98G cells with AKT3 or PI3KCA siRNA and exposure to TMZ and BCNU led to a significant reduction in cell viability, accumulation of subG1-phase cells, and reduction of cells in the S and G2/M phases, as well as induction of apoptosis or necrosis, and regulation of autophagy.
  
  
  CONCLUSIONS
  The siRNA-induced AKT3 and PI3KCA mRNA knockdown in combination with TMZ and BCNU inhibited proliferation and induced apoptosis and autophagy in T98G cells. Thus, knockdown of these genes in combination with TMZ and BCNU may offer a novel therapeutic strategy to more effectively control the growth of human GBM cells, but further studies are necessary to confirm a positive phenomenon for the treatment of GBM.
authors.affiliation: Department of Medical Genetics, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Jedności 8 Street, 41-200, Sosnowiec, Poland. mpaul@sum.edu.pl.
authors.forename: Monika
authors.initials: M
authors.lastname: Paul-Samojedny
authors.affiliation: Department of Clinical Chemistry and Laboratory Diagnostics, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Katowice, Poland.
authors.forename: Adam
authors.initials: A
authors.lastname: Pudełko
authors.affiliation: Department of Medical Genetics, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Jedności 8 Street, 41-200, Sosnowiec, Poland.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Kowalczyk
authors.affiliation: Department of Medical Genetics, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Jedności 8 Street, 41-200, Sosnowiec, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Fila-Daniłow
authors.affiliation: Department of Medical Genetics, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Jedności 8 Street, 41-200, Sosnowiec, Poland.
authors.forename: Renata
authors.initials: R
authors.lastname: Suchanek-Raif
authors.affiliation: Department of Medical Genetics, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Jedności 8 Street, 41-200, Sosnowiec, Poland.
authors.forename: Paulina
authors.initials: P
authors.lastname: Borkowska
authors.affiliation: Department of Medical Genetics, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Jedności 8 Street, 41-200, Sosnowiec, Poland.
authors.forename: Jan
authors.initials: J
authors.lastname: Kowalski
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D017209:Apoptosis / Q000187:drug effects; D001343:Autophagy / Q000187:drug effects; D001932:Brain Neoplasms / Q000188:drug therapy* / Q000235:genetics; D002330:Carmustine / Q000008:administration & dosage; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003606:Dacarbazine / Q000008:administration & dosage / Q000031:analogs & derivatives; D005909:Glioblastoma / Q000188:drug therapy* / Q000235:genetics; D006801:Humans; D009687:Nuclear Proteins / Q000235:genetics*; D051057:Proto-Oncogene Proteins c-akt / Q000235:genetics*; D034741:RNA, Small Interfering / Q000235:genetics*; D015398:Signal Transduction / Q000187:drug effects; D000077204:Temozolomide; D014157:Transcription Factors / Q000235:genetics*
chemical_list: D009687:Nuclear Proteins; C503859:PI3KCA protein, human; D034741:RNA, Small Interfering; D014157:Transcription Factors; D003606:Dacarbazine; C491754:AKT3 protein, human; D051057:Proto-Oncogene Proteins c-akt; D002330:Carmustine; D000077204:Temozolomide