XAF1 expression and regulatory effects of somatostatin on XAF1 in prostate cancer cells

Characterisation of key biomarkers in diabetic ulcers via systems bioinformatics

Diabetic ulcers (DUs) are characterised by a high incidence and disability rate. However, its pathogenesis remains elusive. Thus, a deep understanding of the underlying mechanisms for the pathogenesis of DUs has vital implications. The weighted gene co-expression network analysis was performed on the main data from the Gene Expression Omnibus database. Gene Ontology (GO) terms, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were adopted to analyse the potential biological function of the most relevant module. Furthermore, we utilised CytoHubba and protein-protein interaction network to identify the hub genes. Finally, the hub genes were validated by animal experiments in diabetic ulcer mice models. The expression of genes from the turquoise module was found to be strongly related to DUs. GO terms, KEGG analysis showed that biological functions are closely related to immune response. The hub genes included IFI35, IFIT2, MX2, OASL, RSAD2, and XAF1, which were higher in wounds of DUs mice than that in normal lesions. Additionally, we also demonstrated that the expression of hub genes was correlated with the immune response using immune checkpoint, immune cell infiltration, and immune scores. These data suggests that IFI35, IFIT2, MX2, OASL, RSAD2, and XAF1 are crucial for DUs.

Chelerythrine chloride induces apoptosis in renal cancer HEK-293 and SW-839 cell lines

Previous studies have demonstrated that the benzo[c]phenanthridine alkaloid chelerythrine chloride (CC) has inhibitory effects on various tumors. However, the anticancer activity of CC and its underlying mechanisms have not been elucidated in renal cancer cells. The present study examined the effects of CC on growth inhibition and apoptosis of renal cancer cells in vitro and in vivo. Flow cytometry and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays revealed that CC markedly suppressed the growth of HEK-293 and human renal cancer SW-839 cells in a time- and dose-dependent manner. The xenograft mouse model, which was performed in nude mice, exhibited a reduced tumor growth following CC treatment. In addition, the present study revealed that CC significantly decreased the phosphorylation of extracellular signal-regulated kinase (ERK) and Akt, which was accompanied by upregulation of p53, B-cell lymphoma 2 (Bcl-2)-associated X protein, cleaved caspase-3 and cleaved poly (adenosine diphosphate-ribose) polymerase (PARP), and downregulation of Bcl-2, caspase-3 and PARP. Furthermore, the use of PD98059, a specific mitogen-activated protein kinase kinase inhibitor, potentiated the proapoptotic effects of CC, which indicated that CC may induce apoptosis in renal cancer cells partly via inhibition of ERK activity. Overall, the results of the present study demonstrated that CC may be developed as a potential anticancer treatment for patients with renal cancer.

SULF2 overexpression positively regulates tumorigenicity of human prostate cancer cells

Background

SULF2 is a 6-O-endosulfatase which removes 6-O sulfate residues from N-glucosamine present on heparan sulfate (HS). The sulfation pattern of HS influences signaling events mediated by heparan sulfate proteoglycans (HSPGs) located on cell surface, which are critical for the interactions with growth factors and their receptors. Alterations in SULF2 expression have been identified in the context of several cancer types but its function in cancer is still unclear where the precise molecular mechanism involved has not been fully deciphered. To further investigate SULF2 role in tumorigenesis, we overexpressed such gene in prostate cancer cell lines.

Methods

The normal prostate epithelial cell line RWPE-1 and the prostate cancer cells DU-145, and PC3 were transfected with SULF2-expressing plasmid pcDNA3.1/Myc-His(−)-Hsulf-2. Transfected cells were then submitted to viability, migration and colony formation assays.

Results

Transfection of DU-145 and PC3 prostate cancer cells with SULF2 resulted in increased viability, which did not occur with normal prostate cells. The effect was reverted by the knockdown of SULF2 using specific siRNAs. Furthermore, forced expression of SULF2 augmented cell migration and colony formation in both prostate cell lines. Detailed structural analysis of HS from cells overexpressing SULF2 showed a reduction of the trisulfated disaccharide UA(2S)-GlcNS(6S). There was an increase in epithelial-mesenchymal transition markers and an increase in WNT signaling pathway.

Conclusions

These results indicate that SULF2 have a pro-tumorigenic effect in DU-145 and PC3 cancer cells, suggesting an important role of this enzyme in prostatic cancer metastasis.

Somatostatin derivative (smsDX) targets cellular metabolism in prostate cancer cells after androgen deprivation therapy

Cancer cell metabolism responsive to androgen deprivation therapy (ADT) may be involved in the development and progression of prostate cancer and the ultimate failure of androgen-deprivation therapy. To investigate the metabolism regulation effects on androgen-independent growth of prostate cancer, an established LNCaP-s cell model that resembles the clinical scenario of castration-resistant prostate cancer (CRPC), was used in this current study. This cell line was cultured from androgen-sensitive LNCaP parental cells, in an androgen-reduced condition, resembling clinical androgen deprivation therapy. To assess the effects of smsDX on the invasiveness of prostate cancer cells we used wound healing assay and Matrigel™ invasion assay. We evaluated differentially expressed proteins of the parental LNCaP cells and LNCaP-s cells after ADT by means of two-dimensional gel electrophoresis (2-DE) followed by MALDI-TOF mass spectrometric analysis. The covered area in the wound and the number of cells invading through a Matrigel chamber were significantly smaller for cells treated with smsDX than they were for control cells treated with vehicle. 56 proteins were found differentially expressed in LNCaP-s cells compared to LNCaP cells, majority of them were down-regulated after ADT treatment. 104 proteins of LNCaP cells and 86 in LNCaP-s cells, separately, were found differentially expressed after treatment with smsDX, When we explored these protein functions within the website UniProtKB/Swiss-Prot, surprisingly, most of the proteins were found to be involved in the cellular metabolism and mitochondrial function regulation. LNCaP-s as potential metastatic androgen-independent cancer cells, its metabolism and mitochondrial functions could be altered by a new somatostatin derivative smsDX, the smsDX regulatory effects on metabolism in LNCaP-s deliver more therapeutic information with the treatment of CRPC.

EZH2 is required for breast and pancreatic cancer stem cell maintenance and can be used as a functional cancer stem cell reporter

Although cancer is largely seen as a disease stemming from genetic mutations, evidence has implicated epigenetic regulation of gene expression as a driving force for tumorigenesis. Epigenetic regulation by histone modification, specifically through polycomb group (PcG) proteins such as EZH2 and BMI-1, is a major driver in stem cell biology and is found to be correlated with poor prognosis in many tumor types. This suggests a role for PcG proteins in cancer stem cells (CSCs). We hypothesized that epigenetic modification by EZH2, specifically, helps maintain the CSC phenotype and that in turn this epigenetic modifier can be used as a reporter for CSC activity in an in vitro high-throughput screening assay. CSCs isolated from pancreatic and breast cancer lines had elevated EZH2 levels over non-CSCs. Moreover, EZH2 knockdown by RNA interference significantly reduced the frequency of CSCs in all models tested, confirming the role of EZH2 in maintenance of the CSC population. Interestingly, genes affected by EZH2 loss, and therefore CSC loss, were inversely correlated with genes identified by CSC enrichment, further supporting the function of EZH2 CSC regulation. We translated these results into a novel assay whereby elevated EZH2 staining was used as a reporter for CSCs. Data confirmed that this assay could effectively measure changes, both inhibition and enrichment, in the CSC population, providing a novel approach to look at CSC activity. This assay provides a unique, rapid way to facilitate CSC screening across several tumor types to aid in further CSC-related research.

New Agonist- and Antagonist-Based Treatment Approaches for Advanced Prostate Cancer

Increased understanding of prostate cancer biology has led to new treatment strategies and promising new agents for treating prostate cancer, in particular peptide-based agonists and antagonists. In this review article, new therapy modalities and potential approaches for the treatment of advanced prostate cancer are discussed, including agonists and antagonists of luteinizing hormone-releasing hormone, antagonists of bombesin/gastrin-releasing peptide, and growth hormone-releasing hormone and somatostatin analogues. Though the prognosis of patients with prostate cancer is much improved by some of these treatment approaches, including combination treatment methods, extensive side-effects are still reported. These include sexual dysfunction, functional lesions of the liver and renal system, osteoporosis, anaemia and diarrhoea. Future studies should focus on new treatment agents and treatment approaches that can eliminate side-effects and improve quality of life in patients with prostate cancer on the basis of potent treatment efficacy.