Although recent studies have demonstrated the anti-tumor effects of garlic extract (GE), the exact molecular mechanism is still unclear. In this study, we investigated the molecular mechanism associated with the inhibitory action of GE against bladder cancer EJ cell responses. Treatment with GE significantly inhibited proliferation of EJ cells dose-dependently through G2/M-phase cell cycle arrest. This G2/M-phase cell cycle arrest by GE was due to the activation of ATM and CHK2, which appears to inhibit phosphorylation of Cdc25C (Ser216) and Cdc2 (Thr14/Tyr15), this in turn was accompanied by down-regulation of cyclin B1 and up-regulation of p21WAF1. Furthermore, GE treatment was also found to induce phosphorylation of MAPK (ERK1/2, p38MAPK, and JNK) and AKT. In addition, GE impeded the migration and invasion of EJ cells via inhibition of MMP-9 expression followed by decreased binding activities of AP-1, Sp-1, and NF-κB motifs. Based on microarray datasets, we selected Heat shock protein A6 (HSPA6) as the most up-regulated gene responsible for the inhibitory effects of GE. Interestingly, overexpression of HSPA6 gene resulted in an augmentation effect with GE inhibiting proliferation, migration, and invasion of EJ cells. The augmentation effect of HSPA6 was verified by enhancing the induction of G2/M-phase-mediated ATM-CHK2-Cdc25C-p21WAF1-Cdc2 cascade, phosphorylation of MAPK and AKT signaling, and suppression of transcription factor-associated MMP-9 regulation in response to GE in EJ cells. Overall, our novel results indicate that HSPA6 reinforces the GE-mediated inhibitory effects of proliferation, migration, and invasion of EJ cells and may provide a new approach for therapeutic treatment of malignancies.

MicroRNAs (miRs) serve either as oncogenes or tumor-suppressor genes in tumor progression. MicroRNA-20b (miR‑20b) is known to be involved with the oncomirs of several types of cancers. However, in the present study we describe how miR-20b inhibits the proliferation, migration and invasion of bladder cancer EJ cells. In the present study, miR-20b was downregulated in bladder cancer cell lines, and its overexpression resulted in a significant reduction in the proliferation of EJ cells. In addition, via a bioinformatics approach, we identified cell cycle-regulated genes that are the putative targets of miR-20b. The transfection of miR-20b into EJ cells induced G1 phase cell cycle arrest via the decreased expression of cyclin D1, CDK2 and CDK6 without affecting another G1 phase cell cycle regulator, cyclin E. The cell cycle inhibitor p21WAF1 was upregulated in the miR-20b transfected cells. Moreover, the enforced expression of miR-20b resulted in impaired wound-healing migration and invasion in the EJ cells. Based on our target prediction analysis of miRs, we confirmed that miR-20b overexpression strongly impedes MMP-2 expression via suppressive activation of the Sp-1 binding motif, an important transcription factor present in the MMP-2 promoter. Herein, we report the novel concept that miR-20b exerts a suppressive effect on both cell cycle-modulated proliferation and MMP-2-mediated migration and invasion in bladder cancer EJ cells.

The pharmacological effects of Rosa hybrida are well known in the cosmetics industry. However, the role of Rosa hybrida in cardiovascular biology had not previously been investigated, to the best of our knowledge. The aim of the present study was to elucidate the effect of water extract of Rosa hybrida (WERH) on platelet‑derived growth factor (PDGF)-stimulated vascular smooth muscle cells (VSMCs). VSMC proliferation, which was stimulated by PDGF, was inhibited in a non-toxic manner by WERH treatment, which also diminished the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and AKT. Treatment with WERH also induced G1-phase cell cycle arrest, which was due to the decreased expression of cyclins and cyclin-dependent kinases (CDKs), and induced p21WAF1 expression in PDGF-stimulated VSMCs. Moreover, WERH treatment suppressed the migration and invasion of VSMCs stimulated with PDGF. Treatment with WERH abolished the expression of matrix metalloproteinase-9 (MMP-9) and decreased the binding activity of nuclear factor-κB (NF-κB), activator protein-1 (AP-1), and specificity protein 1 (Sp1) motifs in PDGF-stimulated VSMCs. WERH treatment inhibited the proliferation of PDGF‑stimulated VSMCs through p21WAF1‑mediated G1-phase cell cycle arrest, by decreasing the kinase activity of cyclin/CDK complexes. Furthermore, WERH suppressed the PDGF-induced phosphorylation of ERK1/2 and AKT in VSMCs. Finally, treatment with WERH impeded the migration and invasion of VSMCs stimulated by PDGF by downregulating MMP-9 expression and a reduction in NF-κB, AP-1 and Sp1 activity. These results provide new insights into the effects of WERH on PDGF-stimulated VSMCs, and we suggest that WERH has the potential to act as a novel agent for the prevention and/or treatment of vascular diseases.

Preclinical Research Previous studies have shown that morin exerts diverse pharmacological activities. In this study, we investigated the inhibitory activity of morin on bladder cancer EJ cells. Morin significantly inhibited EJ cell proliferation, which was related to the G1-phase cell cycle arrest together with the reduced expression of cyclin D1, cyclin E, CDK2, and CDK4 via increased expression of p21WAF1. Morin also increased ERK1/2 phosphorylation and decreased JNK and AKT phosphorylation without altering the p38MAPK phosphorylation levels. Morin treatment suppressed the migration and invasion of EJ cells in wound-healing and transwell cell invasion assays. Zymographic and electrophoretic mobility shift assays showed that morin suppressed the expression of matrix metalloproteinase-9 (MMP-9) via repression of the binding activity of AP-1, Sp-1, and NF-κB. Collectively, these results demonstrate that morin reduced cyclin D1, cyclin E, CDK2 and CDK4 expression via the induction of p21WAF1 expression, increased ERK1/2 phosphorylation and decreased JNK, and AKT phosphorylation, and prevented MMP-9 expression via the inhibition of transcription factors AP-1, Sp-1, and NF-κB, thereby resulting in the inhibition of growth, migration, and invasion of bladder cancer EJ cells. These results provide a novel insight into the use of morin in the prevention of bladder cancer. Drug Dev Res 78 : 81-90, 2017. © 2017 Wiley Periodicals, Inc.

Hyper-proliferation and migration of vascular smooth muscle cells (VSMCs) are closely associated with atherosclerosis. Recently, the flavonol morin has been reported to exhibit potent anti-oxidant and anti-inflammatory activities. Therefore, we investigated molecular mechanisms of morin in VSMCs stimulated by PDGF. Morin effectively inhibited PDGF-stimulated proliferation of VSMCs through a G1 cell-cycle arrest, leading to down-regulation of CDK2, CDK4, cyclin D1, and cyclin E proteins. Interestingly, PDGF markedly down-regulated p27KIP1 protein expression; however, morin treatment restored the p27KIP1expression to the basal level. Morin did not affect phosphorylation of MAPKs (ERK, p38, and JNK); however, phosphorylation of AKT was dramatically suppressed by morin in PDGF-stimulated VSMCs. Using the PI3K inhibitor, LY294002, we revealed that AKT is a key regulator in the inhibitory mechanism of morin against PDGF-induced proliferation of VSMCs. Morin disturbed migratory and invasive potential of VSMCs via suppression of matrix metalloproteinase-9 (MMP-9) activity. Using electrophoretic mobility shift assays, we verified that NF-κB, AP-1, and Sp-1 transcription factors are implicated in the mode of action of morin, which suppresses the MMP-9 activity in PDGF-induced VSMCs. Based on the results, we believe that morin may be a potential therapeutic agent for atherosclerosis without negative side effect.