title: Quantum dot imaging for HSP70 and HSF‑1 kinetics in SCC‑25 cells with or without leucine deprivation following heat shock.
abstract: The aim of this study was to develop a quantum dot-based approach for heat shock protein 70 (HSP70) and heat shock factor 1 (HSF-1) kinetics following heat shock, and to discover approaches to thermotherapy based on disrupting the effect of activation of HSF-1 and the accumulation of HSP70 by leucine deprivation. SCC-25 cells cultured with limiting leucine or normal leucine were stressed at 42˚C for 30 min, and were cultured for 2, 4, 6, 8 and 10 h, respectively. The expression of HSP70 and HSF-1 was observed using confocal laser microscopy and semi-quantitative analysis was performed by Image-Pro Plus. At 6 h after heating, HSF-1 in cells cultured with normal leucine was activated and translocated from the cytosol to the nucleus, and the synthesis of HSP70 reached the maximum value and had a tendency to gather in the nucleus. However, in cells cultured with limiting leucine, HSF-1 activity decreased and accumulation of HSP70 was not found. Leucine deprivation results in the inactivation of HSF-1 leading to slight accumulation of HSP70 and no tendency to gather in the nucleus. Thus, HSF-1 may serve as a novel therapeutic target in the treatment of oral cancer.
authors.affiliation: Guangdong Provincial Stomatological Hospital, Southern Medical University, Guangzhou, Guangdong 510280, PR China.
authors.forename: Jun
authors.initials: J
authors.lastname: Chen
authors.forename: Jie
authors.initials: J
authors.lastname: Pan
authors.forename: Jianjiang
authors.initials: J
authors.lastname: Zhao
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Qiu
authors.forename: Junfa
authors.initials: J
authors.lastname: Zheng
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Wang
authors.forename: Yuhua
authors.initials: Y
authors.lastname: Huang
authors.forename: Hongxing
authors.initials: H
authors.lastname: Chu
mesh_terms: D045744:Cell Line, Tumor; D004268:DNA-Binding Proteins / Q000378:metabolism*; D005456:Fluorescent Dyes / Q000737:chemistry; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism*; D000076249:Heat Shock Transcription Factors; D018869:Heat-Shock Response; D006801:Humans; D007700:Kinetics; D007930:Leucine / Q000378:metabolism*; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D045663:Quantum Dots; D013194:Staining and Labeling / Q000379:methods; D014157:Transcription Factors / Q000378:metabolism*
chemical_list: D004268:DNA-Binding Proteins; D005456:Fluorescent Dyes; C000619706:HSF1 protein, human; D018840:HSP70 Heat-Shock Proteins; D000076249:Heat Shock Transcription Factors; D014157:Transcription Factors; D007930:Leucine