Exposure to low-frequency electromagnetic fields does not alter HSP70 expression or HSF-HSE binding in HL60 cells.

C A Morehouse; R D Owen

doi:10.1667/0033-7587(2000)153[0658:etlfef]2.0.co;2

Home/Archive/PubMed

PubMed · 10790289

Exposure to low-frequency electromagnetic fields does not alter HSP70 expression or HSF-HSE binding in HL60 cells.

C A Morehouse·R D Owen

View original source ↗Export metadata ↓

Abstract

Environmental exposure to extremely low-frequency electromagnetic fields (ELF EMFs) has been identified as a possible contributor to increased cancer incidence and other diseases. In vitro studies designed to probe for biological mechanisms that might explain such relationships have included several studies of gene expression. While gene expression studies have focused on MYC, effects of ELF EMFs on the expression of beta-actin, histone H2B, beta-tubulin, SRC, FOS and JUN have also been reported. In addition, some investigators have reported both an induction of HSP70 expression and an increase in HSF-HSE binding in HL60 (human promyelocytic leukemia) cells after exposure to a 60 Hz magnetic field. In this study, HL60 cells were exposed to a weak 60 Hz magnetic field (6.3 or 8.0 microT) or to a positive control heat shock (42 or 44 degrees C). While heat shock led to reproducible induction of HSP70 expression and HSF-HSE binding, no significant effect of exposure to ELF EMFs on either of these end points was observed.

Explore related subjects

Blotting, Northern DNA DNA-Binding Proteins Dose-Response Relationship, Radiation Electromagnetic Fields Electrophoresis, Agar Gel Gene Expression HL-60 Cells HSP70 Heat-Shock Proteins Heat Shock Transcription Factors Heat-Shock Response Hot Temperature Humans Promoter Regions, Genetic Protein Binding Reproducibility of Results Transcription Factors Journal Article Research Support, U.S. Gov't, P.H.S.

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

C A Morehouse, R D Owen. 2000. Exposure to low-frequency electromagnetic fields does not alter HSP70 expression or HSF-HSE binding in HL60 cells.. https://doi.org/10.1667/0033-7587(2000)153%5B0658%3Aetlfef%5D2.0.co%3B2

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2025

Northern Blotting: Protocols for Radioactive and Nonradioactive Detection of RNA.

Northern blotting is a common technique in RNA biology, allowing to detect and quantify RNAs of interest following separation by gel electrophoresis, transfer to a membrane, and hybridization of specific anti-complementary labelled probes. In this chapter, we describe our protocol for efficient RNA extraction from yeast, separation on agarose gel, and capillary transfer to a membrane. We provide two different methods for strand-specific detection of several types of RNAs using oligonucleotide probes, the first using radioactive 32P-labelled probes, the second based on nonradioactive digoxigenin-labelled probes.

Blotting, Northern↗

PubMed2007

Osteoprotegerin expression in dendritic cells increases with maturation and is NF-kappaB-dependent.

Dendritic cells (DC) comprise a unique leukocyte population which controls primary immune responses. Recent studies indicate that DC express osteoprotegerin (OPG), a secreted tumor necrosis factor receptor homolog, which regulates DC survival, monocyte chemotaxis, and B cell development and function by ligating TNF family member receptor activator of NF-kappaB ligand (RANKL). The precise regulators of OPG expression in DC have not been investigated. In this study, we assessed OPG mRNA steady state levels by Northern blot analysis and OPG protein secretion by an immunoassay in monocyte-derived DC of different maturation, and the effect of different cytokines and hormones on OPG expression. OPG was upregulated with maturation of DC, whereas pretreatment of DC with 1alpha,25(OH)(2) vitamin D(3), tamoxifen, or dexamethasone, agents that inhibit differentiation of DC, decreased OPG expression. In vivo, OPG was found to be colocalized with mature CD83(+) DC in human tonsils by immunofluorescence confocal microscopy analysis. Furthermore, OPG was upregulated by TNF superfamily members TNF-alpha, anti-CD40, and RANKL, and by ligands of the Toll-like/IL-1 receptor family including IL-1beta, double-stranded RNA (poly I:C), or lipopolysaccharide (LPS), all of which induce maturation of DC. Gene silencing by small interfering RNA (siRNA) directed against transcription factor NF-kappaB abrogated the expression of OPG as demonstrated by real-time PCR. In summary, we describe that the expression of OPG by DC increases with maturation and is NF-kappaB-dependent, possibly regulating immune responses in lymphoid tissues.

Blotting, Northern↗

PubMed2007

Up-regulation of fibroblast growth factor 3 is associated with tumor metastasis and recurrence in human hepatocellular carcinoma.

Recently, we established a hepatocellular carcinoma (HCC) cell line (named H4-M) from a metastatic HCC tumor. In H4-M, a marker chromosome containing a homogeneously staining region (hsr) was identified by cytogenetic analysis. The hsr was characterized by chromosome microdissection and the result showed that the hsr was composed of DNA sequence from 11q13. Oncogenes CCND1 and FGF3 were localized within the complicon and overexpressions of CCND1 and FGF3 were confirmed by Northern blot analysis. Clinical significance of FGF3 overexpression was studied by immunohistochemistry (IHC) using an HCC tissue microarray (TMA) containing 60 pairs of primary/metastatic HCCs and 30 pairs of primary/recurrent HCCs. TMA study showed that overexpression of FGF3 was significantly associated with HCC metastasis and recurrence (p<0.01), suggesting that up-regulation of FGF3 may play an important role in HCC metastasis and recurrence.

Blotting, Northern↗