Signal transduction of gap junctional genes, connexin32, connexin43 in human hepatocarcinogenesis

Abstract

AIM:To inve s ti ga te ga p ju n ct io na l i nt er c el lu la r communication (GJIC) in hepatocellular carcinoma cell lines, and signal transduction mechanism of gap junction genes connexin32(cx32),connexin43(cx43) in human hepatocarcinogenesis. METHODS:Scarped loading and dye transfer (SLDT) was employed with Lucifer Yellow (LY) to detect GJIC function in hepatocellular carcinoma cell lines HHCC, SMMC-7721 and normal control liver cell line QZG. After Fluo-3AM loading, laser scanning confocal microscope (LSCM) was used to measure concentrations of intracellular calcium [Ca 2+ ]i in the cells. The phosphorylation on tyrosine of connexin proteins was examined by immunoblot. RESULTS:SLDT showed that ability of GJIC function was higher in QZG cell than that in HHCC and SMMC-7721 cell lines. By laser scanning confocal microscopy, concentrations of intracellular free calcium [Ca

Liver cell lines for the study of hepatocyte functions and immunological response

“…We therefore assessed the gap junction intercellular communication (GJIC) in the novel cell lines by the transfer of LY‐CH. The molecular mass of LY‐CH is sufficiently small at 457 Da to allow free passage of the dye into adjacent cells via the gap junctions, thus indicating that the gap junctions are intact and allow intercellular communication (33). Following iontophoretic injection of LY‐CH, the cells were examined for transfer of the dye to neighbouring cells.…”

Modifications in Connexin Expression in Liver Development and Cancer

“…In addition, in cultures of primary hepatocytes, which are inherently prone to alterations in the differentiation status and thus can serve as an experimental model to study this condition, inhibitors of histone deacetylases, constituting another critical determinant of the epigenome, have been demonstrated to affect connexin expression and GJIC in favour of the differentiated status (Vinken et al, 2006c(Vinken et al, , 2007. Another hallmark of tumour cells includes aberrant connexin localisation (Leithe et al, 2006;Ma et al, 2000Ma et al, , 2002Ma et al, , 2003Mesnil et al, 2005). Thus, Cx32 typically accumulates in the cytoplasm of cancerous human hepatocytes, both in vitro and in vivo (Kawasaki et al, 2011;Li et al, 2007).…”

Efficacy of continuous positive airway pressure on TNF-α in obstructive sleep apnea patients: A meta-analysis

“…TNF-α is an important mediator of the immune response. Chronic inflammatory injury involving numerous inflammatory factors such as TNF-α, C-reactive protein, interleukin-6 (IL-6), and interleukin-8 (IL-8) is the leading cause of cardiovascular and cerebrovascular complications [ 10 , 11 ]. In OSAHS patients, an increase in serum TNF-α affects lipid metabolism and energy consumption, resulting in weight gain and metabolic disorders [ 12 ].…”