Quanlin Li

Diagnostic value of SFRP1 as a favorable predictive and prognostic biomarker in patients with prostate cancer.

Growing genetic and molecular biological evidence suggests that the disruption of balance between Secreted Frizzled-Related Protein-1 (SFRP1) and β-catenin plays an important role in the initiation and development of multiple cancers. The aim of this study was to examine whether the expression of SFRP1 and β-catenin is associated with the clinical-pathologic features of patients with prostate cancer (PCa), and to evaluate their potential roles as predictive and prognostic biomarkers. In this study, a total of 61 patients with PCa and 10 patients with benign prostatic hyperplasia were included, and we showed that the expression of SFRP1 and β-catenin was correlated with the Gleason score, survival rate and response for endocrine therapy of PCa. The survival rates of PCa patients with low SFRP1 expression (P = 0.016) or high β-catenin expression (P = 0.004) were significantly poorer. A negative correlation (r = -0.275, P = 0.032) between SFRP1 and β-catenin was observed by Chi-square test. Multivariate analysis suggested that SFRP1 (hazard ratio, 0.429; 95% confidence intervals, 0.227–0.812; P = 0.009) may serve as an independent predictive and prognostic factor for PCa. We also showed that the protein and mRNA levels of SFRP1 in androgen-dependent PCa cell line LNCaP were significantly higher than those in androgen-independent PCa cell lines DU145 and PC3. However, the protein level of β-catenin in LNCaP cells was significantly lower than that in DU145 and PC3 cells, and no significant difference of β-catenin mRNA level was observed in LNCaP, DU145 and PC3 cells. Bisulfite sequencing PCR assay revealed significantly lower methylation level of SFRP1 promoter in LNCaP cells than that in DU145 and PC3 cells. Taken together, these findings suggest that SFRP1, which expression inversely correlates with that of β-catenin, is a favorable predictive and prognostic biomarker.

arsenic trioxide inhibits viability and induces apoptosis through reactivating the Wnt inhibitor secreted frizzled related protein-1 in prostate cancer cells

Background Growing evidence suggests that arsenic trioxide (As2O3) induces apoptosis and inhibits tumor cell growth in prostate cancer (PCa), although details of the mechanism are still inconclusive. We investigated the antitumor effect of As2O3 in human PCa cell lines LNCaP and PC3 and the underlying mechanisms by focusing on the Wnt signaling pathway. Methods The effect of As2O3 on the viability and apoptosis of PCa cells was investigated by cholecystokinin-8 and flow cytometry. The expression of the related proteins in the Wnt signaling pathway and the downstream target genes of the Wnt signaling pathway was examined by Western blot and quantitative real-time PCR assay. The methylation status of the SFRP1 gene promoter was assessed by bisulfite sequencing. Results As2O3 inhibited the viability of PCa cells and induced apoptosis of PCa cells in a dose-dependent manner. The protein level of phosphoglycogen synthase kinase-3β was upregulated, whereas the protein level of β-catenin and the mRNA levels of c-MYC, MMP-7, and COX-2 were downregulated in a dose-dependent manner in PCa cells treated with As2O3. In addition, As2O3 upregulated the protein and mRNA levels of secreted frizzled related protein-1, and increased the demethylation of the SFRP1 gene promoter. Conclusion Our results suggest that As2O3 may inhibit cell viability and induce apoptosis through reactivating the Wnt inhibitor secreted frizzled related protein-1 in both androgen-dependent and -independent human PCa.

In vitro anticancer activities of osthole against renal cell carcinoma cells

Renal cell carcinoma (RCC) is a common urinary malignancy that is resistant to chemotherapy and radiotherapy. Osthole, a monomer compound extracted from a traditional Chinese herb, has potent anti-tumor effects on various types of cancer cells. However, the therapeutic effects of osthole on RCC remain unclear. In our study, osthole could suppress the proliferation and colony formation of two RCC cell lines, ACHN and 786-O cells, in a dose-dependent manner. Treatment with osthole resulted in a significant, dose-dependent increase in the expression of pro-apoptotic proteins (cleaved caspase-3 and Bax) and decreased expression of anti-apoptotic proteins (Bcl-2 and survivin), which were consistent with evidence of apoptotic nuclear morphology revealed by DAPI staining. Pre-treatment with osthole attenuated the migratory and invasive abilities of RCC cells in a dose-dependent manner, as evidenced by a reduction in migrating cells in a Transwell assay and a decreased wound closure ratio in a scratch assay as compared with the control. Additionally, osthole down-regulated the expression of migration/invasion-related proteins matrix metalloproteinase (MMP)-2 and MMP-9. Osthole significantly up-regulated epithelial biomarkers (E-cadherin and beta-catenin) and down-regulated mesenchymal biomarkers (N-cadherin and vimentin). Furthermore, our results suggest that osthole suppressed the expression of epithelial-mesenchymal transition transcriptional factors Smad-3, Snail-1, and Twist-1. Taken together, the results of this study suggest that osthole might be a potential novel herbal agent against RCC.

PIM1 mediates epithelial-mesenchymal transition by targeting Smads and c-Myc in the nucleus and potentiates clear-cell renal-cell carcinoma oncogenesis

Emerging evidence has shown that the PIM serine/threonine kinase family, including PIM1, PIM2 and PIM3, is associated with tumour progression towards metastasis. PIM1, an attractive molecular target, has been identified as a potential prognostic biomarker for haematological and epithelial malignancies. However, to date, the potential regulatory roles and molecular mechanisms by which PIM1 affects the development and progression of cancers, including clear-cell renal-cell carcinoma (ccRCC), remain largely unknown. Herein, we present the first evidence that PIM1 is aberrantly overexpressed in human ccRCC tissues and cell lines and positively correlated with human ccRCC progression. In our study, depletion of PIM1 attenuated ccRCC cell proliferation, colony formation, migration, invasion and angiogenesis, suggesting that PIM1 expression may be a cancer-promoting event in ccRCC. Mechanistically, we observed that PIM1 could interact with Smad2 or Smad3 in the nucleus and subsequently phosphorylate Smad2 and Smad3 to induce the expression of transcription factors, including ZEB1, ZEB2, Snail1, Snail2 and Twist, to promote epithelial-mesenchymal transition (EMT). In addition, PIM1-mediated phosphorylation of c-Myc activates the expression of the above transcription factors to synergistically promote EMT but does not activate Smads. Collectively, our results demonstrate that aberrant expression of PIM1 contributes to ccRCC development and progression. Moreover, our data reveal a potential molecular mechanism in which PIM1 mediates crosstalk between signalling pathways, including different Smad proteins and c-Myc, which target downstream transcription factors (ZEB1, ZEB2, Snail1, Snail2 and Twist) to trigger EMT. Together, our data suggest that PIM1 may be a potential therapeutic target for ccRCC patients.

Salinomycin suppresses cancer cell stemness and attenuates TGF-β-induced epithelial-mesenchymal transition of renal cell carcinoma cells

Metastatic Renal cell carcinoma (RCC) remains a difficult oncologic challenge. Salinomycin is a monocarboxylic polyether antibiotic, which has been proved to possess anti-tumor activities in multiple types of cancer cells. However, its effects on RCC cells remains unclear. In our study, salinomycin could inhibit the proliferation and viability of RCC cell lines 786-O and ACHN. The TUNEL assay revealed that treatment with salinomycin induced DNA breaking in RCC cells. Consistently, Western blotting showed up-regulation of pro-apoptotic biomarkers (cleaved caspase3/9 and cleaved PARP1) and down-regulation of anti-apoptotic biomarker (survivin) in RCC cells after salinomycin treatment, suggesting that salinomycin could induce RCC cell apoptosis. salinomycin treatment also suppressed the sphere formation ability of RCC cells and decreased the expressions of CD105, ALDH1 and CD44, biomarkers for reflecting the stemness of RCC cells. salinomycin treatment effectively down-regulated SMO and Gli1, two key proteins in Hedghog signaling pathway, in a dose-dependent manner. Moreover, salinomycin could suppress the invasion and migration of RCC cells in the presence of TGF-β1, as observed in wound-healing and Transwell assays. salinomycin treatment attenuated TGF-β1-induced epithelial-mesenchymal transition (EMT), as evidenced by its ability to increase E-cadherin expression and decrease N-cadherin, Snail and MMP-2 expressions in RCC cells. Finally, salinomycin inhibited the tumorigenecity of RCC cells in vivo. Our study provides the evidence that salinomycin possess multiple anti-tumor activities against RCC, as it, in particular, suppressed the cancer stem cell properties and attenuated TGF-β-induced EMT. Therefore, it may serve as a potentially therapeutic candidate for metastatic RCC and improve the prognosis of RCC patients.

Sinomenine hydrochloride attenuates the proliferation, migration, invasiveness, angiogenesis and epithelial-mesenchymal transition of clear-cell renal cell carcinoma cells via targeting Smad in vitro

New strategies for the treatment of clear-cell renal cell carcinoma (ccRCC) are urgently needed. Recently, accumulating evidence has demonstrated that sinomenine hydrochloride (SH), extracted from the plant sinomenium acutum, has potent anti-cancer activity in multiple human malignant solid tumors. However, the underlying molecular mechanism by which SH treatment exerts its antagonizing tumorigenic effects has not been clearly elucidated. In this study, we showed that SH treatment exerted profound effects on cell growth in ccRCC in a dose- and time-dependent manner in vitro. Furthermore, treatment with SH significantly suppressed the migration, invasiveness and angiogenesis of ccRCC cells in vitro. Mechanistically, we revealed that SH treatment blocked epithelial-mesenchymal transition (EMT) through the downregulation of the expression of the transcription factors Snail1 and Twist in ccRCC cells. Additionally, the depletion of p-Smad2 and p-Smad3 was required for SH treatment to inhibit EMT effectively. Taken together, these findings indicate an anti-cancer role for SH in ccRCC cells and reveal a potential molecular mechanism by which Smad / EMT axis functions in ccRCC, as its hyperactivation has been associated with cell proliferation, migration, invasiveness and angiogenesis in this cancer type. These observations suggest that SH can act as an efficacious adjuvant chemotherapeutic candidate that targets the Smad/EMT axis in patients with ccRCC.

Nodal activates smad and extracellular signal-regulated kinases 1/2 pathways promoting renal cell carcinoma proliferation.

Expression of the nodal gene is high in a number of tumor cell types and may promote tumor growth. The expression of lefty, an inhibitor of nodal is often reduced in tumor cells. To the best of our knowledge, few studies have investigated the expression of nodal and lefty in renal cell carcinoma (RCC) cells. In the present study, quantitative polymerase chain reaction assays demonstrated that the level of nodal expression in RCC cells was high compared with that of adjacent non-tumor tissue cells, while the opposite pattern was observed for the level of lefty expression. Furthermore, lefty overexpression in RCC cells inhibited the expression of nodal. Nodal overexpression promoted RCC cell proliferation and invasion, and inhibited RCC cell apoptosis. Nodal downregulation and lefty overexpression led to similar observations: The inhibition of RCC cell proliferation and invasion, and the promotion of RCC cell apoptosis. The results of the present study suggested that the expression of nodal promoted RCC growth by activating the smad and extracellular signal-regulated kinases 1/2 pathways. The expression of lefty in RCC cells was lower than that in adjacent non-tumor cells, which may result in the overexpression of nodal, thereby promoting the growth of RCC. The results of the present study may therefore be useful for the development of novel biomarkers for RCC tumor diagnosis, and suggest a potential target gene for the treatment of RCC.