title: Modulating Heat Shock Proteins 70 and 90 Expression by Low Power Laser Irradiation (635nm and 780nm) in Jurkat E6.1 T-lymphocyte Leukemia Cell Line.
abstract: BACKGROUND
  Heat shock proteins (HSPs) are molecular chaperones involved in protein folding, stability and turnover, and due to their role in cancer progression, the effect of low power laser irradiation (LPLI) on the expression of HSP70 and HSP90 in Jurkat E6.1 T-lymphocyte leukemia (JELT) cell line was investigated in vitro.
  
  
  METHODS
  JETL cells were irradiated with LPLI at 635nm and 780m wavelengths (energy density 9.174 J/cm(2)), and assessed for the expression of HSP70 and HSP90 by flow cytometry after 24, 48 and 72 incubation time periods (ITPs).
  
  
  RESULTS
  At 24 hours ITP post-irradiation, control cultures showed that 10.7% of cells expressed HSP70, while LPLI cultures at 635nm and 780nm manifested a higher expression (32.1and 21.3%, respectively), and the difference was significant (P ≤ 0.05). However, at 48 hours ITP, the three means were decreased but approximated (5.6, 4.9 and 6.2%, respectively), while at 72 hours ITP, they were markedly increased (45.2, 76.5 and 66.7%, respectively). In contrast, HSP90 responded differently to LPLI. At 24 hours ITP, control cultures and 780nm cultures showed a similar expression (55.9 and 55.9%, respectively), but both means were significantly higher than that of 635nm cultures (24.0%). No such difference was observed at 48 hours ITP, and at 72 hours ITP, control cultures and 635nm cultures shared approximated means (31.7 and 35.6%, respectively); but both means were significantly higher than the observed mean in 780nm cultures (15.2%).
  
  
  CONCLUSIONS
  The results highlighted that HSP70 and HSP90 expression responded differently to LPLI in JETL cells; an observation that may pave the way for further investigations in malignant cells.
authors.affiliation: Tropical-Biological Research Unit, College of Science, University of Baghdad, Jadirya, Baghdad, Iraq.
authors.forename: Ali Hussein
authors.initials: AH
authors.lastname: Ad'hiah
authors.affiliation: Tropical-Biological Research Unit, College of Science, University of Baghdad, Jadirya, Baghdad, Iraq.
authors.forename: Layla Mohammed Hassan
authors.initials: LM
authors.lastname: Al-Ameri
authors.affiliation: Institute of Laser for Postgraduate Studies, University of Baghdad, Baghdad, Iraq.
authors.forename: Amel Mustfa
authors.initials: AM
authors.lastname: Maki
authors.affiliation: School of Healthcare Science, Manchester Metropolitan University, Manchester, UK.
authors.forename: Qiuyu
authors.initials: Q
authors.lastname: Wang
authors.affiliation: School of Healthcare Science, Manchester Metropolitan University, Manchester, UK.
authors.forename: Mayada Hameed
authors.initials: MH
authors.lastname: ALQaisi
keywords: Heat shock proteins; Jurkat cell; laser Irradiation; leukemia cell; low-Power