Dongbin Bi

Gene expression patterns combined with network analysis identify hub genes associated with bladder cancer

OBJECTIVES To explore molecular mechanisms of bladder cancer (BC), network strategy was used to find biomarkers for early detection and diagnosis. METHODS The differentially expressed genes (DEGs) between bladder carcinoma patients and normal subjects were screened using empirical Bayes method of the linear models for microarray data package. Co-expression networks were constructed by differentially co-expressed genes and links. Regulatory impact factors (RIF) metric was used to identify critical transcription factors (TFs). The protein-protein interaction (PPI) networks were constructed by the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) and clusters were obtained through molecular complex detection (MCODE) algorithm. Centralities analyses for complex networks were performed based on degree, stress and betweenness. Enrichment analyses were performed based on Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. RESULTS Co-expression networks and TFs (based on expression data of global DEGs and DEGs in different stages and grades) were identified. Hub genes of complex networks, such as UBE2C, ACTA2, FABP4, CKS2, FN1 and TOP2A, were also obtained according to analysis of degree. In gene enrichment analyses of global DEGs, cell adhesion, proteinaceous extracellular matrix and extracellular matrix structural constituent were top three GO terms. ECM-receptor interaction, focal adhesion, and cell cycle were significant pathways. CONCLUSIONS Our results provide some potential underlying biomarkers of BC. However, further validation is required and deep studies are needed to elucidate the pathogenesis of BC.

miR-1301 promotes prostate cancer proliferation through directly targeting PPP2R2C

Prostate cancer is the leading cause of cancer deaths among men in the worldwide, its important to find new prognostic factors and therapeutic targets. microRNAs play critical roles in the development and progression of prostate cancer. Here we revealed miR-1301 promoted prostate cancer progression. miR-1301 was upregulated in prostate cancer tissues and cells, overexpression of miR-1301 promoted anchorage-dependent and -independent growth using MTT analysis, colony formation analysis and soft agar growth analysis, whereas knockdown of miR-1301 suppressed anchorage-dependent and -independent growth. We also found overexpression of miR-1301 inhibited p27 expression and promoted Cyclin D1 expression, whereas knockdown of miR-1301 reduced this effect, suggesting miR-1301 promoted the G1/S transition. These results suggested miR-1301 promoted cell proliferation of prostate cancer. microRNAs can inhibit target mRNA translation or/and induce mRNA degradation, we found tumor suppresser PPP2R2C was the target of miR-1301, simultaneous downregualtion of PPP2R2C and miR-1301 promoted anchorage-dependent and -independent growth. These findings suggested miR-1301 promoted prostate cancer proliferation by inhibiting PPP2R2C, and might a therapeutic target for prostate cancer.

A Potent Chemotherapeutic Strategy with Eg5 Inhibitor against Gemcitabine Resistant Bladder Cancer

Development of resistance to gemcitabine is a major concern in bladder cancer therapy, and the mechanism remains unclear. Eg5 has been recently identified as an attractive target in cancer chemotherapy, so novel targeted chemotherapy with Eg5 inhibitor is expected to improve the anticancer effect in gemcitabine-resistant bladder cancer. In this research, RT112-Gr cells were 350-fold less sensitive to gemcitabine than the parental cell lines, while KU7-Gr cells were 15-fold less sensitive to gemcitabine than the parental cell lines. Human OneArray Microarray analysis was performed to obtain broad spectrum information about the genes differentially expressed in RT112 and RT112-Gr cells. The anti-proliferative activity of S(MeO)TLC, an Eg5 inhibitor, was analyzed in RT112-Gr cell lines using a cell viability assay. Furthermore, the inhibitory effect was evaluated in vivo using subcutaneous xenograft tumor model. According to the result of Human OneArray® GeneChip, RRM1 and RRM2 were up-regulated, while there was no significant change in Eg5. Trypan blue staining confirmed that in S(MeO)TLC and Gemcitabine combining S(MeO)TLC group cell viability were significantly decreased in RT112-Gr cells as compared with other groups. S(MeO)TLC and S(MeO)TLC+gemcitabine groups prominently suppressed tumor growth in comparison with other groups’ in vivo. There were no significant differences in S(MeO)TLC and gemcitabine+S(MeO)TLC group in the effect of inhibition of bladder cancer in vivo and in vitro. Our data collectively demonstrated that S(MeO)TLC represents a novel strategy for the treatment of gemcitabine resistant bladder cancer.

Elevated expression of HIF-lα in actively growing prostate tissues is associated with clinical features of benign prostatic hyperplasia

Background Benign prostatic hyperplasia (BPH) is one of the most common diseases in middle-age or older men. Increasing evidence has shown that BPH is associated with hypoxia microenvironment. Methods We retrospectively collected patient data and tissue samples from fetal prostates(FP), normal prostates(NP), intra-acinar of BPH, peri-acinar of BPH, prostate cancers and sarcomas of prostate. The expression of HIF-1α, as well as VEGF was visualized by immunohistochemistry and statistically analyzed with clinical parameters. Results Expression of HIF-lα was observed in intra-acinar of BPH (69.5%), prostate cancer (85.7%) and all FPs, while NP and peri-acinar of BPH tissues were all stained negative. HIF-lα levels in FPs and the malignant tumors were higher than BPH tissues(p < 0.05), and the expression of HIF-lα in intra-acinar of BPH was higher than NP and peri-acinar of BPH (p < 0.05). The expression of HIF-lα was correlated with the weight of intra-acinar of prostate (p < 0.05). And patients with prostate weight larger that 72.45g were prone to have HIF-lα moderate-positive expression, according to the ROC curve (AUC = 0.734, 95%CI = 0.630-0.838). Moreover, the risk of acute urine retention (AUR) for HIF-lα moderate-positive patients increased significantly (OR=5.517, 95%CI = 2.434-12.504). Conclusions HIF-lα expression is increased in highly proliferative prostate tissues and correlated with the weight of intra-acinar prostate. Moreover, HIF-lα is also an independent risk factor for AUR occurrence in BPH patients.

Invasive Epithelioid Angiomyolipoma with Tumor Thrombus in the Inferior Vena Cava: A Case Report and Literature Review

Renal angiomyolipoma (AML) is a benign tumor. However, rare cases of renal AML demonstrate aggressive behaviors such as tumor thrombus extension into the inferior vena cava (IVC). We successfully treated a case of epithelioid AML in the right kidney involving the IVC. We also reviewed and analyzed 45 case reports of the common type of AML. Radiologists and clinicians should know that epithelioid AML can be an aggressive tumor.

CYLD downregulates Livin and synergistically improves gemcitabine chemosensitivity and decreases migratory/invasive potential in bladder cancer: the effect is autophagy-associated

Although GC (gemcitabine and cisplatin) chemotherapy remains an effective method for treating bladder cancer (BCa), chemoresistance is a major obstacle in chemotherapy. In this study, we determined whether gemcitabine resistance correlates with migratory/invasive potential in BCa and whether this relationship is regulated by the cylindromatosis (CYLD)-Livin module. First, we independently investigated the correlation of CYLD/Livin and gemcitabine resistance with the potential for tumor migration and invasiveness. Second, we found that co-transfected CYLD and Livin dramatically improved sensitivity to gemcitabine chemotherapy and decreased migration/invasion potential. Next, we determined that CYLD may regulate Livin by the NF-κB-dependent pathway. We also found that CYLD overexpression and Livin knockdown might improve gemcitabine chemosensitivity by decreasing autophagy and increasing apoptosis in BCa cells. Finally, the effects of CYLD-Livin on tumor growth in vivo were evaluated. Our study demonstrates that CYLD-Livin might represent a potential therapeutic for chemoresistant BCa.

Ubenimex inhibits cell proliferation, migration and invasion by inhibiting the expression of APN and inducing autophagic cell death in prostate cancer cells

Prostate cancer is the second most frequently diagnosed cancer in males worldwide and is commonly associated with metastasis. Moreover, in prostate cancer, aminopeptidase N (APN) expression is closely correlated with metastasis. Ubenimex, an APN inhibitor, is widely used as an adjunct therapy for cancer, enhancing the function of immunocompetent cells and conferring antitumor effects. However, due to the low expression of APN, it is rarely used to treat prostate cancer. Recently, the induction of autophagy as a molecular mechanism has been strongly connected with tumor cell death. Thus, we investigated whether ubenimex could inhibit cell proliferation, migration and invasion by downregulating APN expression to induce autophagic cell death in prostate cancer cells. The LNCaP and PC-3 cell lines were treated with different doses of ubenimex. Cell viability was measured using growth curve analysis and WST-8 proliferation assay. Autophagic cell death was assessed using fluorescence microscopy and acridine orange/ethidium bromide (AO/EB) staining. Protein expression was assessed by immunofluorescence and western blot analyses. Autophagosomes were evaluated using transmission electron microscopy. Wound-healing migration assays were performed to determine the migratory ability of the PC-3 cells. In addition, nude mice were used in the present study to examine PC-3 cell proliferation in vivo. The results revealed that APN expression differed between the metastatic and non-metastatic prostate cancer cells. In addition, ubenimex inhibited APN expression in the prostate cancer cells. Ubenimex increased prostate cancer cell death, as determined using the lactate dehydrogenase (LDH) cytotoxicity assay. This effect was accompanied by increased levels of LC3B. Furthermore, ubenimex inhibited PC-3 cell proliferation in vivo and in vitro. Ubenimex inhibited the cell migration and invasion in prostate cancer cells by downregulating APN expression. Finally, ubenimex induced autophagic cell death in both metastatic and non-metastatic prostate cancer cells. Based on these results, ubenimex appears to be an excellent adjunctive therapy for the treatment of prostate cancer.

HCRP1 regulates proliferation, invasion, and drug resistance via EGFR signaling in prostate cancer

Previous studies showed that HCRP1 is decreased in tumor cells compared with normal tissue, and functions as a tumor suppressor. However, its expression pattern and function in human prostate cancer remain unclear. In this study we examined HCRP1 expression in prostate cancer cell lines via western blotting. Thereafter, we performed CCK-8 assay and matrigel invasion assay after cells were transfected with HCRP1 overexpression plasmid or siRNA. We further investigated the possible mechanism involved in HCRP1s regulation to prostate cancer cell proliferation and invasion. We found that HCRP1 negatively regulates EGFR activity and expression of its downstream proteins. Moreover, we found that HCRP1 is negatively correlated with multi-drug resistant related proteins after cells were treated with paclitaxel, cisplatin or gefitinib, indicating its inhibiting effect of chemotherapy resistance. In summary, our results provided evidence that HCRP1 is a negative regulator in prostate cancer progression, metastasis and multi-drug resistance.