The Inhibitory Effect of PDIA6 Downregulation on Bladder Cancer Cell Proliferation and Invasion.

Protein disulfide isomerases A6 (PDIA6) belongs to the PDI family. Recently, PDIA6 was found to have a close association with various cancers. However, there has been little investigation into the biological functions of PDIA6 in bladder cancer (BC). In this study, we explored the expression pattern and functional significance of PDIA6 in BC. We found that PDIA6 was overexpressed in BC tissues and cell lines. The in vitro study showed that PDIA6 downregulation significantly inhibited BC proliferation and invasion. In addition, the in vivo experiment demonstrated that PDIA6 downregulation decreased the volume, weight, and metastasis of tumors. Furthermore, PDIA6 downregulation reduced the protein expression of ß-catenin, cyclin D1, and c-Myc and thus suppressed the Wnt/ß-catenin signaling pathway. In conclusion, we suggest that PDIA6 could be targeted for the treatment of BC.

Clinicopathological Significance of Matrix Metalloproteinase-2 Protein Expression in Renal Cell Carcinoma Patients.

OBJECTIVE: To conduct a metaanalysis in order to determine the association between matrix metalloproteinase (MMP)-2 expression and renal cell carcinoma (RCC) progression. STUDY DESIGN: Cohort studies were identified after an exhaustive search of the following electronic databases: PubMed, China Biomedicine, Web of Science, Wanfang database, and China National Knowledge Infrastructure. Summary odds ratios with 95% confidence interval were calculated. RESULTS: Seventeen clinical studies were eligible for the present metaanalysis. Overall, increased MMP-2 protein expression levels had a positive correlation with several RCC clinical parameters, such as tumor node metastasis (TNM) stage, differentiation grade, lymph node metastasis (LNM), and tumor size (all p < 0.05). Country-stratified analysis revealed statistically significant differences in MMP-2 expression levels, based on the 4 clinical parameters studied, in the Chinese population (all p < 0.05). The results indicated that the MMP-2 protein level in RCC patients with non-clear cell type was higher than that in the patients with clear cell carcinoma (p < 0.05). A positive correlation was found between RCC differentiation grade and MMP-2 protein levels in only the streptavidin-peroxidase subgroup (p < 0.05), while there were significant associations between MMP-2 protein level and TNM stage, LNM, and tumor size (p < 0.05). CONCLUSION: Our metaanalysis suggests that RCC patients with a high MMP-2 expression level exhibit rapid progression of RCC and that high MMP-2 expression level is associated with poor prognosis.

[Expression of Smad4 in prostate cancer LNCaP and ARCaP cell lines with different metastatic potentials and its significance].

OBJECTIVE: To observe the expression of Smad4, the core of TGF-beta/Smads signal transduction pathway in different prostate cancer cell lines, and explore their molecular mechanism of bone metastatic potential. METHODS: The Millicell polycarbonate filter coated with matrigel was used to confirm the invasive potency of LNCaP and ARCaP cell lines (IF11 and IA8). The expressions of the Smad4 protein and mRNA in these prostate cancer cells with different metastatic potentials were detected by Western blotting and RT-PCR, respectively. RESULTS: ARCaP cell lines (IF11 and IA8) exhibited a stronger potency of invasion than LNCaP (P < 0.01). The Smad4 protein and mRNA highly expressed in the LNCaP cell line that was well-known with a low metastatic potential, but not in the ARCaP (IF11 or IA8) cells with high metastatic potentials (P < 0.01). CONCLUSION: Smad4 expresses differently in LNCaP and ARCaP cell lines with different metastatic potentials and, as a tumor suppressive gene, its deficient expression may play an important role in the invasion and metastasis of advanced prostate cancer.

[Over-expression of hypoxia-inducible factor 1 alpha increases angiogenesis of LNCaP cells in vivo].

OBJECTIVE: To observe the influence of hypoxia-inducible factor 1 alpha (HIF-1alpha) on angiogenesis in prostate carcinoma in vivo and to investigate its molecular mechanism. METHODS: LNCaP/HIF-1alpha and LNCaP cells were cultured, the level of PSA in the supernatant of the culture medium detected by ELISA assay before and after the transfection, and the cellular cycle measured by flow cytometry. Nude mouse models of subcutaneous tumor were established with LNCaP/HIF-1alpha and LNCaP cells, the tumor growth observed, and tumor specimens collected for immunohistochemical staining. RESULTS: Compared with the LNCaP cells, LNCaP/HIF-1alpha cells showed an obviously decreased PSA level (t = 8.243, P < 0.05) and enhanced proliferous activity. The tumorigenesis rate increased and the tumorigenesis time advanced in the LNCaP/HIF-1alpha group of the nude mice. Immunohistochemistry displayed higher expressions of VEGF, iNOS and Ang-2 in the LNCaP/HIF-1alpha than in the LNCaP group. CONCLUSION: The over-expression of HIF-1alpha can up-regulate VEGF and iNOS involved in angiogenesis in vivo and contribute to the invasive potency of LNCaP cells. HIF-1alpha may have no influence on Ang-2 either in vitro or in vivo, while the expression of Ang-2 is regulated by other factors in vivo.

[Transforming growth factor beta upregulates the expression of invasion and metastasis associated proteins in prostate cancer LNCaP cell lines in vitro].

OBJECTIVE: To determine the effect of the transforming growth factor beta (TGF-beta) on the expression of invasion and metastasis associated proteins in the prostate cancer LNCaP cell line in vitro. METHODS: The prostate cancer cell line LNCaP was treated with TGF-beta in vitro. Western blotting was used to detect the expression of the "invasion and metastasis" associated proteins E-Cadherin, N-Cadherin and Vimentin. RESULTS: The expression of N-Cadherin and Vimentin of the LNCaP cells treated with TGF-beta for 12 hours was significantly upregulated, but not that of E-Cadherin. CONCLUSION: TGF-beta may induce epithelial-mesenchymal transition (EMT) of LNCaP cells which might be of importance in promoting prostate cancer cells invading to ambient tissues and metastasizing to distant organs.

Effect of long-term partial bladder outlet obstruction on caldesmon isoforms and their correlation with contractile function.

AIM: In the present study, we investigate the expression of caldesmon (CAD) isoforms in rabbit detrusor smooth muscles (DSM) during the progression of partial bladder outlet obstruction and relate them with the time course of obstruction. METHODS: Detrusor samples were obtained from the bladders of rabbits with partial bladder outlet obstruction and sham-operated control rabbits after 1, 2, 4, and 8 weeks of obstruction. Contractile responses to field stimulation and carbachol were determined in the isolated bladder strips. Western blotting was used to determine the relative levels of CaD isoform expression at the protein levels. RESULTS: The contractile responses decreased progressively over the course of obstruction. The expression of l-CaD increased significantly to approximately the same extent as the 1-4-week obstructed groups and further in the 8-week obstructed group. The expression of h-CaD increased in all of the obstructed bladders, but at significantly higher levels in the 1-2-week obstructed bladders compared to the control and 4-8-week obstructed bladders. CONCLUSIONS: The changes in the isoforms of CaD may be part of the molecular mechanism for bladder compensation following partial bladder outlet obstruction. The overexpression of l-CaD and the h-CaD/l-CaD ratio could be markers for the status of DSM remodeling and dysfunction.

[Over-expression of hypoxia-inducible factor-1 alpha increases angiogenesis of LNCaP cells].

OBJECTIVE: To evaluate the effect of hypoxia-inducible factor-1 alpha (HIF-la) on angiogenesis in human prostate cancer cells. METHODS: Human prostate cancer cells of the line LNCaP were cultured and transfected by the recombinant plasmid pcDNA3. 1(-)/HIF-1alpha containing the gene HIF-1alpha with the Lipofectamine 2000 system. The positive clone cells were selected by G418 and confirmed by Western blotting and immunofluorescence (LNCaP/HIF-1alpha cells). The expressions of VEGF, iNOS and Ang-2 were detected by Western blotting. RESULTS: The expression of HIF-1alpha in the LNCaP/HIF-1alpha cells was distinctly higher than that in the LN-CaP cells. Compared with the LNCaP cells, the expressions of VEGF and iNOS were up-regulated, whereas Ang-2 remained unchanged in the LNCaP/HIF-1alpha cells. CONCLUSION: The over-expression of HIF-1alpha can induce an increase in angiogenesis proteins and improve the angiogenesis potency of prostate cancer.