Bisphenol A exposure inhibits vascular smooth muscle cell responses: Involvement of proliferation, migration, and invasion.

Previous studies have associated bisphenol A (BPA) with malignant tumor formation, infertility, and atherosclerosis in vitro and in vivo. However, the precise mechanisms through which BPA affects the cardiovascular system under normal conditions remain unclear. Therefore, this study investigated the biological mechanisms through which BPA affects the responses of aortic vascular smooth muscle cells (VSMCs). BPA treatment inhibited the proliferative activity of VSMCs and induced G2/M-phase cell cycle arrest via stimulation of the ATM-CHK2-Cdc25C-p21WAF1-Cdc2 cascade in VSMCs. Furthermore, BPA treatment upregulated the phosphorylation of mitogen-activated protein kinase (MAPK) pathways such as ERK, JNK, and p38 MAPK in VSMCs. However, the phosphorylation level of AKT was down-regulated by BPA treatment. Additionally, the phosphorylation of ERK, JNK, and p38 MAPK was suppressed when the cells were treated with their respective inhibitors (U0126, SP600125, and SB203580). BPA suppressed MMP-9 activity by reducing the binding activity of AP-1, Sp-1, and NF-κB, thus inhibiting the invasive and migratory ability of VSMCs. These data demonstrate that BPA interferes with the proliferation, migration, and invasion capacities of VSMCs. Therefore, our findings suggest that overexposure to BPA can lead to cardiovascular damage due to dysregulated VSMC responses.

Scaffold-Free Coculture Spheroids of Human Colonic Adenocarcinoma Cells and Normal Colonic Fibroblasts Promote Tumorigenicity in Nude Mice.

The aim of this study was to form a scaffold-free coculture spheroid model of colonic adenocarcinoma cells (CACs) and normal colonic fibroblasts (NCFs) and to use the spheroids to investigate the role of NCFs in the tumorigenicity of CACs in nude mice. We analysed three-dimensional (3D) scaffold-free coculture spheroids of CACs and NCFs. CAC Matrigel invasion assays and tumorigenicity assays in nude mice were performed to examine the effect of NCFs on CAC invasive behaviour and tumorigenicity in 3D spheroids. We investigated the expression pattern of fibroblast activation protein-α (FAP-α) by immunohistochemical staining. CAC monocultures did not form densely-packed 3D spheroids, whereas cocultured CACs and NCFs formed 3D spheroids. The 3D coculture spheroids seeded on a Matrigel extracellular matrix showed higher CAC invasiveness compared to CACs alone or CACs and NCFs in suspension. 3D spheroids injected into nude mice generated more and faster-growing tumors compared to CACs alone or mixed suspensions consisting of CACs and NCFs. FAP-α was expressed in NCFs-CACs cocultures and xenograft tumors, whereas monocultures of NCFs or CACs were negative for FAP-α expression. Our findings provide evidence that the interaction between CACs and NCFs is essential for the tumorigenicity of cancer cells as well as for tumor propagation.

Characterization of the cytokine profile of platelet rich plasma (PRP) and PRP-induced cell proliferation and migration: Upregulation of matrix metalloproteinase-1 and -9 in HaCaT cells.

BACKGROUND: The underlying rationale of platelet rich plasma (PRP) therapy is that an injection of concentrated PRP at the site of injury may promote tissue repair via cytokine release from platelets. The molecular mechanisms of PRP therapy in the skin wound healing process are not well understood at present, and would benefit from clarification. METHODS: PRP was stimulated with angonists for 5 min, and cytokine profile analysis was performed. To investigate the wound healing activity of PRP, cell proliferation and migration analyses were performed in skin cells. The effects of PRP were analyzed on the expression and activity of matrix metalloproteinase (MMP)-1, -2, -9, and the activation of transcription factors. RESULTS: Thrombin was found to be a strong stimulator of PRP activation to release growth factors and chemokines. PRP induced cell proliferation and migration in HUVECs, HaCaT cells, and HDFs, as well as MMP-1and MMP-9 expression in HaCaT cells, but PRP did not have a significant effect on the expression or activity of MMPs in HDFs. The transcription factors, including signal transducer and activator of transcription-3 (STAT-3) were found to be phosphorylated following PRP treatment in HaCaT cells. CONCLUSION: In this study, we have identified the cytokine profile of activated PRP after agonist stimulation. We have shown that PRP plays an active role in promoting the proliferation and migration of skin cells via the regulation of MMPs, and this may be applicable to the future development of PRP therapeutics to enhance skin wound healing.