Effect of Photobiomodulation on Protein Kinase Cδ, Cytochrome C, and Mitochondria in U87 MG Cells

C-X-C motif chemokine receptor 4 inhibition promotes the effect of plantamajoside in hepatocellular carcinoma

BACKGROUND AND STUDY AIM

Hepatocellular carcinoma (HCC) is the fifth leading cause of cancer-related mortality worldwide, and, more than half of these cases are diagnosed in China. However, effective treatment for HCC is still limited.

MATERIAL AND METHODS

C-X-C motif chemokine receptor 4 (CXCR4) was first activated and inhibited in HepG2 cells using a pharmacological method. HepG2 cell proliferation was detected using the CCK-8 method. Metastasis and apoptosis of HepG2 cells were detected using wound healing and flow cytometry. The expression of each target molecule related to metastasis and invasion, such as MMPs, E-cadherin and the PI3K/AKT/Mcl-1/PARP signaling pathway was detected by western blotting. The secretion of molecular metastases was detected using competitive ELISA.

RESULTS

This study constructed a CXCR4 activation and inhibition model in HepG2 cells. CXCR4 inhibition promoted the inhibitory effect of plantamajoside on the proliferation and metastasis of cells, which led to apoptosis. Furthermore, we found that the expression of apoptosis-related proteins was increased after treatment with plantamajoside combined with CXCR4 inhibition. In addition, the expression and secretion of pro-metastatic proteins, including MMPs and E-cadherin were decreased. We also noticed that this effect might be mediated by the PI3K/AKT/Mcl-1/PARP signaling pathway.

CONCLUSION

CXCR4 inhibition may contribute to the treatment of HCC. Inhibition of CXCR4 expression contributes to the therapeutic effect of plantamajoside; the effect of plantamajoside might be mediated by the PI3K/AKT/Mcl-1/PARP signaling pathway; and CXCR4 might be a therapeutic target of HCC.

The Remodulation of Actin Bundles during the Stimulation of Mitochondria in Adult Human Fibroblasts in Response to Light

β-actin belongs to cytoskeletal structures that change dynamically in cells according to various stimuli. Human skin can be considered as an organ that is very frequently exposed to various stress factors, of which light plays an important role. The present study focuses on adult human fibroblasts exposed to two types of light stress. Orange light with a wavelength of 590 nm was used here to stimulate the photosensitizer localized in the cells as a residual dose of photodynamic therapy (PDT). On the other hand, near-infrared light with a wavelength of 808 nm was considered for photobiomodulation (PBM), which is often used in healing processes. Confocal fluorescence microscopy was used to observe changes in intercellular communication, mitochondrial structures, and cytoskeletal dynamics defined by the remodulation of β-actin of fibroblasts. The number of β-actin bundles forming spherical structures was detected after light exposure. These structures as β-actin oligomers were confirmed with super-resolution microscopy. While PDT led to the disintegration of actin oligomers, PBM increased their number. The interaction of β-actin with mitochondria was observed. The combination of PDT and PBM treatments is important to minimize the side effects of cancer treatment with PDT on healthy cells, as shown by the cell metabolism assay in this work. In this work, β-actin is presented as an important parameter that changes and is involved in the response of cells to PDT and PBM.