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Drug resistance is the predominant cause of mortality in late-stage patients with ovarian cancer. Histone deacetylase inhibitors (HDACis) have emerged as a novel type of second line drug with high specificity for tumor cells, including ovarian cancer cells. However, HDACis usually exhibit relatively low potencies when used as a single agent. The majority of current clinical trials are combination strategies. These strategies are more empirical than mechanism-based applications. Previously, it was reported that the adhesion molecule cluster of differentiation 146 (CD146) is significantly induced in HDACi-treated tumor cells. The present study additionally confirmed that the induction of CD146 is a common phenomenon in vorinostat-treated ovarian cancer cells. AA98, an anti-CD146 monoclonal antibody (mAb), was used to target CD146 function. Synergistic antitumoral effects between AA98 and vorinostat were examined in vitro and in vivo. The potential effect of combined AA98 and vorinostat treatment on the protein kinase B (Akt) pathway was determined by western blotting. The present study found that targeting of CD146 substantially enhanced vorinostat-induced killing via the suppression of activation of Akt pathways in ovarian cancer cells. AA98 in combination with vorinostat significantly inhibited cell proliferation and increased apoptosis. In vivo, AA98 synergized with vorinostat to inhibit tumor growth and prolong survival in ovarian cancer. These data suggest that an undesired induction of CD146 may serve as a protective response to offset the antitumor efficacy of vorinostat. By contrast, targeting CD146 in combination with vorinostat may be exploited as a novel strategy to more effectively kill ovarian cancer cells. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the impact of filaggrin knockdown on the function of normal human epidermal keratinocytes (NHEKs). Filaggrin expression levels in NHEKs were knocked down by lentivirus (LV) encoding small hairpin RNA (shRNA), with control cells infected with nonsense shRNA or not infected. Cell migration and invasion were assayed using Transwell inserts, cell adhesion and proliferation by the Cell Counting kit-8 assay, and apoptosis and cell cycle progression by flow cytometry. shRNA efficiently suppressed expression of filaggrin protein. The LV group had significantly decreased cell migration, adhesion and proliferation, and increased apoptosis compared with the control groups (P=0.027). In addition, the proportion of cells in G1 and G2 phases were significantly increased in the LV group compared with control groups (P=0.018). The results of the present study demonstrate that filaggrin knockdown inhibits NHEK migration, adhesion and proliferation, promotes apoptosis and disturbs cell cycle progression. [ABSTRACT FROM AUTHOR]

Background Stromal cell-derived factor-1 (SDF-1) plays a critical role in adult brain injury repair including neurogenesis and vasculogenesis. However, the effects of recombinant SDF-1(rSDF-1) treatment on hypoxic-ischemic (HI) brain injury in neonatal mice are not clear. Materials and Methods Seven-day-old (P7) C57BL/6J mice were divided into sham group, control group, and rSDF-1 group. Mice brains were collected to determine histopathological damage and the expression level of SDF-1, caspase-3, and Ki67 on P8, P10, P14, and P21. Passive avoidance and elevated plus-maze tests were also assessed on P20 and P21. Results Compared with control group, rSDF-1 treatment increased the weight ratio of left and right brain hemisphere (p < 0.05), reduced the number of electric foot shocks (p < 0.05) and the percentage of time spent in the open arms (p < 0.05), meanwhile, increased the retention latency (p < 0.05) and the percentage of time spent in the enclosed arms (p < 0.05) on P20 and P21. High expression of Ki67 and low expression of caspase-3 were also observed. Discussion This study showed that rSDF-1 treatment effectively alleviated brain injury shown by reducing in caspase-3 expression and increasing in Ki67 expression. Moreover, rSDF-1 treatment significantly improved behavioral performances in juvenile mice after HI. [ABSTRACT FROM AUTHOR]

: Aims Endothelial progenitor cells (EPCs) are circulating pluripotent vascular cells capable of enhancing re-endothelialization and diminishing neointima formation following arterial injury. Glycogen synthase kinase (GSK)-3β is a protein kinase that has been implicated in the regulation of progenitor cell biology. We hypothesized that EPC abundance and function could be enhanced with the use of an inhibitor of GSK-3β (GSKi), thereby resulting in improved arterial repair. : Methods and results Human EPCs were expanded ex vivo, treated with a specific GSKi, and then assessed for both yield and functional characteristics by in vitro assays for adherence, apoptosis, and survival. In vivo functionality of treated human EPCs was assessed in immune-tolerant mice subjected to femoral artery wire injury. Re-endothelialization was assessed at 72 h and neointima formation at 7 and 14 days following injury. GSKi treatment resulted in an improvement in the yield of EPCs and a reduction in apoptosis in cells derived from both healthy controls and patients with coronary artery disease. Treatment also increased vascular endothelial growth factor secretion, up-regulated expression of mRNA for the α-4 integrin subunit, and improved adhesion, an effect which could be abrogated with an α-4 integrin blocking antibody. EPCs without or with ex vivo GSKi treatment enhanced re-endothelialization 72 h following injury as well as reduced neointima formation at 7 days (e.g. endothelial coverage: 7.2 ± 1.7% vs. 70.7 ± 5.8% vs. 87.2 ± 4.1%; intima to media ratios: 1.05 ± 0.19 vs. 0.39 ± 0.08 vs. 0.14 ± 0.02; P < 0.05 for all comparisons), an effect that was persistent at 14 days. : Conclusion GSKi improves the functional profile of EPCs and is associated with improved re-endothelialization and reduced neointima formation following injury. [ABSTRACT FROM AUTHOR]

Progenitor cell therapy is hindered in patients with diabetes mellitus (DM) due to cellular senescence. Glycogen synthase kinase-3β (GSK3β) activity is increased in DM, potentially exacerbating impaired cell-based therapies. Thus, we aimed to determine if and how GSK3β inhibitors (GSKi) can improve therapeutic efficacy of endothelial progenitor cells (EPC) from patients with DM. Patients with DM had fewer EPCs and increased rates of apoptosis. DM EPCs also exhibited higher levels of GSK3β activity resulting in increased levels of phosphorylated β-catenin. Proteomic profiling of DM EPCs treated with GSKi identified 37 nonredundant, differentially regulated proteins. Cathepsin B (cathB) was subsequently confirmed to be differentially regulated and showed 40% less baseline activity in DM EPCs, an effect reversed by GSKi treatment. Finally, in vivo efficacy of cell-based therapy was assessed in a xenotransplant femoral wire injury mouse model. Administration of DM EPCs reduced the intima-to-media ratio, an effect that was further augmented when DM EPCs were pretreated with GSKi yet absent when cathB was antagonized. In DM, increased basal GSK3β activity contributes to accelerated EPC cellular senescence, an effect reversed by small molecule antagonism of GSK3β, which enhanced cell-based therapy after vascular injury. [ABSTRACT FROM AUTHOR]

Alpha-fetoprotein (AFP)-producing gastric cancer (AFPGC), represented by the production of AFP, has a more aggressive behavior than common gastric cancer. The underlying mechanisms are not well understood. Arsenic trioxide (As2O3) is used clinically to treat acute promyelocytic leukemia(APL) and has activity in vitro against several solid tumor cell lines, with induction of apoptosis and inhibition of proliferation the prime effects. Signal transducer and activator of transcription 3 (STAT3) has an important role in tumorigenesis of various primary cancers and cancer cell by upregulating cell-survival and downregulating tumor suppressor proteins. Here, we found decreased expression of AFP and STAT3 after induction of apoptosis by As2O3 in the AFPGC FU97 cells. Also, the level of the STAT3 target oncogene Bcl-2 was decreased with As2O3, and that of the tumor suppressor Bax was increased. Furthermore, STAT3 expression and depth of invasion and lymph node metastasis were associated. Survival of patients with gastric cancer was lower with AFP and STAT3 double overexpression than with overexpression of either alone. Downregulation of AFP and STAT3 expression plays an important role in As2O3-induced apoptosis of AFPGC cells, which suggests a new mechanism of As2O3-induced cell apoptosis. As2O3 may be a possible agent for AFPGC treatment. [ABSTRACT FROM AUTHOR]