Overexpression of NIMA-related kinase 2 is associated with progression and poor prognosis of prostate cancer.

BACKGROUND: The NIMA-related kinase 2 (NEK2) is a serine/threonine kinase that is involved in regulation of centrosome duplication and spindle assembly during mitosis. Dysregulation of these processes causes chromosome instability and aneuploidy, which are hallmark changes of many solid tumors. However, whether aberrant expression of NEK2 is associated with outcome of prostate cancer (PCa) patients remains to be determined. METHODS: Expression of NEK2 in human PCa cells and primary PCa tissues was assessed by quantitative RT-PCR. Expression of NEK2 in human PCa cells was depleted with siRNA. Effects of the depletion on cell proliferation, survival, and tumorigenicity were assessed both in vitro with cell cultures and in vivo with subcutaneous implantation of xenografts. In silico analyses of the online Taylor dataset were carried out to determine whether the expression level of NEK2 correlated with the clinicopathological characteristics of prostate cancer. RESULTS: Compared with benign human prostatic epithelial cells and tissues, the expression of NEK2 was elevated in human PCa cells and primary PCa tissues. Depleting NEK2 expression inhibited human PCa cell proliferation in vitro and xenograft growth in vivo. Expression level of NEK2 in PCa positively correlated with the Gleason score and pathologic stage of the patient. CONCLUSION: The results suggest that overexpression of NEK2 has the potential to serve as a biomarker for PCa prognosis. Further validation with large sample pool is warrant.

Down-regulation of dual-specificity phosphatase 5 predicts poor prognosis of patients with prostate cancer.

Dual-specificity phosphatase 5 (DUSP5), which specifically inactivates the extracellular signal-regulated kinase (ERK) 1/2 within the mitogen-activated protein kinase (MAPK) signaling, has recently been considered to be a tumor suppressor. However, its role in prostate cancer is still elusive. In this study, we performed immunohistochemistry analysis on human tissue microarray (TMA) to detect the DUSP5 protein expression pattern. The results indicated that DUSP5 was down-regulated in the human prostate cancer relative to the adjacent benign tissues (IRS: PCa = 4.29 ± 1.72 versus Benign = 4.89 ± 1.58, P = 0.04). In addition, when we linked the DUSP5 protein levels to the clinicopathological features of the patients, we found that the downregulation of DUSP5 was significantly associated with advanced pathological stage (P = 0.004) and high Gleason score (P = 0.009). Moreover, we attempted to validate these findings and investigate the prognostic value of DUSP5 in a publicly available microarray-based Taylor Dataset. Statistic analysis demonstrated that the downregulation of DUSP5 was closely correlated with high Gleason score (P = 0.011), positive metastasis (P < 0.001) and biochemical recurrence (BCR) (P = 0.016). More importantly, Kaplan-Meier analysis revealed that significant differences between patients with high and low DUSP5 expression level in regard to the BCR-free survival of overall (P = 0.009), non-metastatic (P = 0.006) and patients with Gleason score 7 (P = 0.044). Multivariate analysis by Cox regression indicated that DUSP5 could be an independent predictor for the risk of BCR (HR: 0.41, 95% CI: 0.2-0.82; P = 0.012). In summary, our findings disclose that DUSP5 may be an important tumor suppressor that inhibits the progression of PCa. The downregulation of DUSP5 may accurately predict poor prognosis in PCa patients.

miR-195 Inhibits Tumor Progression by Targeting RPS6KB1 in Human Prostate Cancer.

PURPOSE: To investigate the involvement of hsa-miRNA-195-5p (miR-195) in progression and prognosis of human prostate cancer. EXPERIMENTAL DESIGN: qRT-PCR was performed to detect miR-195 expression in both prostate cancer cell lines and clinical tissue samples. Its clinical significance was statistically analyzed. The roles of miR-195 and its candidate target gene, ribosomal protein S6 kinase, 70 kDa, polypeptide 1 (RPS6KB1) in prostate cancer progression were confirmed on the basis of both in vitro and in vivo systems. RESULTS: miR-195 downregulation in prostate cancer tissues was significantly associated with high Gleason score (P = 0.001), positive metastasis failure (P < 0.001), and biochemical recurrence (BCR, P < 0.001). Survival analysis identified miR-195 as an independent prognostic factor for BCR-free survival of prostate cancer patients (P = 0.022). Then, we confirmed the tumor suppressive role of miR-195 through prostate cancer cell invasion, migration, and apoptosis assays in vitro, along with tumor xenograft growth, angiogenesis, and invasion in vivo according to both gain-of-function and loss-of-function experiments. In addition, RPS6KB1 was identified as a novel direct target of miR-195 through proteomic expression profiling combined with bioinformatic target prediction and luciferase reporter assay. Moreover, the reexpression and knockdown of RPS6KB1 could respectively rescue and imitate the effects induced by miR-195. Importantly, RPS6KB1 expression was closely correlated with aggressive progression and poor prognosis in prostate cancer patients as opposed to miR-195. Furthermore, we identified MMP-9, VEGF, BAD, and E-cadherin as the downstream effectors of miR-195-RPS6KB1 axis. CONCLUSION: The newly identified miR-195-RPS6KB1 axis partially illustrates the molecular mechanism of prostate cancer progression and represents a novel potential therapeutic target for prostate cancer treatment.

MicroRNA-224 and its target CAMKK2 synergistically influence tumor progression and patient prognosis in prostate cancer.

We previously demonstrated that microRNA (miR)-224 expression was significantly reduced in human prostate cancer (PCa) tissues and predicted unfavorable prognosis in patients. However, the underlying mechanisms of miR-224 have not been fully elucidated. In this study, calcium/calmodulin-dependent protein kinase kinase 2 (CAMKK2) was identified as a target gene of miR-224. Then, we found that enforced expression of miR-224 could suppress PCa cell proliferation and cell cycle by regulating the expression of CAMKK2 in vitro. In addition, the expression levels of miR-224 in PCa tissues were negatively correlated with those of CAMKK2 mRNA significantly (Spearman's correlation: r = -0.66, P = 0.004). Moreover, combined low miR-224 expression and high CAMKK2 expression (miR-224-low/CAMKK2-high) was closely correlated with advanced clinical stage (P = 0.028). Furthermore, PCa patients with miR-224-low/CAMKK2-high expression more frequently had shorter overall survival than those in groups with other expression patterns of two molecules. In conclusion, our data offer the convincing evidence that miR-224 and its target gene CAMKK2 may synergistically contribute to the malignant progression of PCa. Combined detection of miR-224 and CAMKK2 expressions represents an efficient predictor of patient prognosis and may be a novel marker which can provide additional prognostic information in PCa.

MicroRNA-224 inhibits progression of human prostate cancer by downregulating TRIB1.

Our previous microarray data showed that microRNA-224 (miR-224) was downregulated in human prostate cancer (PCa) tissues compared with adjacent benign tissues. However, the underlying mechanisms by which miR-224 is involved in PCa remain unclear. In this study, we identified TRIB1 as a target gene of miR-224. Forced expression of miR-224 suppressed PCa cell proliferation, invasion and migration, and promoted cell apoptosis by downregulating TRIB1. Moreover, the expression level of miR-224 in PCa tissues was negatively correlated with that of TRIB1. miR-224 downregulation was frequently found in PCa tissues with metastasis, higher PSA level and clinical stage, whereas TRIB1 upregulation was significantly associated with metastasis. Both miR-224 downregulation and TRIB1 upregulation were significantly associated with poor biochemical recurrence-free survival of patients with PCa. In conclusion, these findings reveal that the aberrant expression of miR-224 and TRIB1 may promote PCa progression and have potentials to serve as novel biomarkers for PCa prognosis.

MicroRNA-30c serves as an independent biochemical recurrence predictor and potential tumor suppressor for prostate cancer.

MicroRNA-30c (miR-30c) acts as a tumor suppressor or a tumor promoter in various human malignancies. However, the involvement of miR-30c in prostate cancer (PCa) is still unclear. The aim of this study was to investigate the molecular function and the clinical significance of miR-30c in PCa. Expression levels of miR-30c in PCa tissues and cells were detected by quantitative real-time-PCR (qRT-PCR). Additionally, the associations of miR-30c expression with clinicopathological features and prognosis in PCa patients were analyzed. The potential role of miR-30c in tumorigenesis of PCa cells was further evaluated by in vitro cell assays. MiR-30c was significantly down-regulated in PCa tissues and cells compared with the corresponding controls (P<0.05). In addition, the downregulation of miR-30c in PCa tissues was significantly associated with higher Gleason score (P=0.009), advanced pathological stage (P=0.016) and biochemical recurrence (P=0.034). Moreover, Kaplan-Meier survival analysis showed that the reduced expression of miR-30c was correlated with shorter biochemical recurrence-free survival (P=0.023). The multivariate analysis also identified miR-30c as an independent prognostic predictor for biochemical recurrence-free survival in patients with PCa. Furthermore, the enforced expression of miR-30c suppressed proliferation, migration and invasion of PCa cells in vitro. Our data indicated the involvement of miR-30c in PCa progression and suggested its potential role as an independent predictor of biochemical recurrence in PCa. On cellular level, miR-30c may function as a tumor suppressor for PCa cells by inhibiting tumor cell proliferation, migration and invasion.

Decreased expression of myosin light chain MYL9 in stroma predicts malignant progression and poor biochemical recurrence-free survival in prostate cancer.

The aim of this study was to investigate the associations of myosin light chain (MYL9) downregulation with tumor progression and prognosis in patients with prostate cancer (PCa). MYL9 protein expression in human PCa and non-cancerous prostate tissues was detected by Western blot and immunohistochemistry analyses, which was validated by microarray-based Taylor data at mRNA level. Then, the associations of MYL9 expression with clinicopathological features and clinical outcome of PCa patients were statistically analyzed. Both Western blot and immunohistochemistry analyses found that MYL9 expression was significantly decreased (both P < 0.001) in PCa tissues compared with those in non-cancerous prostate tissues. In addition, MYL9 was mainly expressed in the cytoplasm of stromal cells of prostate tissues, and the decreased expression of MYL9 in PCa tissues was significantly correlated with the older age of patients (P = 0.011), the higher Gleason score (P < 0.001), the advanced pathological stage (P = 0.002), the presence of metastasis (P < 0.001) and PSA failure (P = 0.001). Furthermore, both univariate and multivariate analyses showed that the downregulation of MYL9 was an independent predictor of shorter overall survival (P = 0.026 and P = 0.009, respectively) and biochemical recurrence-free survival (P = 0.001 and P = 0.002, respectively). Our data strongly confirmed for the first time that the decreased expression of MYL9 may play an important role in tumor progression of PCa. More importantly, the downregulation of MYL9 may efficiently predict both overall and biochemical recurrence-free survivals in PCa patients.

Global analysis of the differentially expressed miRNAs of prostate cancer in Chinese patients.

BACKGROUND: Our recent study showed the global physiological function of the differentially expressed genes of prostate cancer in Chinese patients was different from that of other non-Chinese populations. microRNA are estimated to regulate the expression of greater than 60% of all protein-coding genes. To further investigate the global association between the transcript abundance of miRNAs and their target mRNAs in Chinese patients, we used microRNA microarray approach combined with bioinformatics and clinical-pathological assay to investigate the miRNA profile and evaluate the potential of miRNAs as diagnostic and prognostic markers in Chinese patients. RESULTS: A total of 28 miRNAs (fold change ≥ 1.5; P ≤ 0.05) were differentially expressed between tumor tissue and adjacent benign tissue of 4 prostate cancer patients.10 top Differentially expressed miRNAs were validated by qRT-PCR using all 20 tissue pairs. Compared to the miRNA profile of non-Chinese populations, the current study showed that miR-23b, miR-220, miR-221, miR-222, and miR-205 maybe common critical therapeutic targets in different populations. The integrated analysis for mRNA microarray and miRNA microarray showed the effects of specifically inhibiting and/or enhancing the function of miRNAs on the gene transcription level. The current studies also identified 15 specific expressed miRNAs in Chinese patients. The clinical feature statistics revealed that miR-374b and miR-19a have significant correlations with clinical-pathological features in Chinese patients. CONCLUSIONS: Our findings showed Chinese prostate cancer patients have a common and specific miRNA expression profile compared with non-Chinese populations. The miR-374b is down-regulated in prostate cancer tissue, and it can be identified as an independent predictor of biochemical recurrence-free survival.

Expression of SOCSs in human prostate cancer and their association in prognosis.

Suppressors of cytokine signaling (SOCS) proteins have been identified as negative feedback regulators of cytokine-mediated signaling in various tissues, and demonstrated to play critical roles in tumorigenesis and tumor development of different cancers. The involvement of SOCSs in human prostate cancer (PCa) has not been fully elucidated. Thus, the aim of this study is to investigate the expression patterns and the clinical significance of SOCSs in PCa. The expression changes of SOCSs at mRNA and protein levels in human PCa tissues compared with adjacent benign prostate tissues were, respectively, detected by using real-time quantitative reverse transcriptase-polymerase chain reaction (QRT-PCR) and immunohistochemistry analyses. The associations of SOCSs expression with clinicopathological features and clinical outcome of PCa patients were further statistically analyzed. Among SOCSs, both QRT-PCR and immunohistochemistry analyses found that SOCS2 expression was upregulated (at mRNA level: change ratio = 1.98, P = 0.031; at protein level: 5.12 ± 0.60 vs. 2.68 ± 0.37, P = 0.016) and SOCS6 expression was downregulated (at mRNA level: change ratio = -1.65, P = 0.008; at protein level: 3.03 ± 0.32 vs. 4.0.72 ± 0.39, P = 0.004) in PCa tissues compared with those in non-cancerous prostate tissues. In addition, the upregulation of SOCS2 in PCa tissues was correlated with the lower Gleason score (P < 0.001), the absence of metastasis (P < 0.001) and the negative PSA failure (P = 0.009); the downregulation of SOCS6 tended to be found in PCa tissues with the higher Gleason score (P = 0.016), the advanced pathological stage (P = 0.007), the positive metastasis (P = 0.020), and the positive PSA failure (P = 0.032). Furthermore, both univariate and multivariate analyses showed that the downregulation of SOCS2 was an independent predictor of shorter biochemical recurrence-free survival. Our data offer the convincing evidence for the first time that the dysregulation of SOCS2 and SOCS6 may be associated with the aggressive progression of PCa. SOCS2 may be potential markers for prognosis in PCa patients.

[Effects of PPAR-gamma on the proliferation and glycolysis metabolism of prostate cancer cells].

OBJECTIVE: To investigate the effects of the expression of the PPAR-gamma gene on the proliferation and glycolysis metabolism of prostate cancer cells. METHODS: Using RNAi, we constructed lowly--expressed shRNA-PPARgamma adenoviruses and transfected them to PC3 prostate cancer cells, with blank vectors as controls. Then we detected the proliferation and apoptosis of the cells, glycolysis metabolism related genes and lactate accumulation by CCK-8 kit, and compared the results between the two groups. RESULTS: Compared with the control group, the PPAR-gamma gene expression was obviously inhibited by RNAi in the PC3 cells, and its protein expression was reduced to (26.00 +/- 4.06)%. The proliferation inhibition rate was (39.5 +/- 4.92)% on the 2nd day, and the apoptosis rate was as high as (21.03 +/- 3.08)%. The glycolysis metabolism related gene products (Myc and Glut-1) were significantly decreased, and the lactate concentration was reduced to 69.71% of that of the controls on the 4th day. There were statistically significant differences in the above findings as compared with the control group (P < 0.01). CONCLUSION: PPAR-gamma gene knockdown is expected to be a new way to treat prostate cancer.

SOXs in human prostate cancer: implication as progression and prognosis factors.

BACKGROUND: SOX genes play an important role in a number of developmental processes. Potential roles of SOXs have been demonstrated in various neoplastic tissues as tumor suppressors or promoters depending on tumor status and types. The aim of this study was to investigate the involvement of SOXs in the progression and prognosis of human prostate cancer (PCa). METHODS: The gene expression changes of SOXs in human PCa tissues compared with non-cancerous prostate tissues was detected using gene expression microarray, and confirmed by real-time quantitative reverse transcriptase-polymerase chain reaction (QRT-PCR) analysis and immunohositochemistry. The roles of these genes in castration resistance were investigated in LNCaP xenograft model of PCa. RESULTS: The microarray analysis identified three genes (SOX7, SOX9 and SOX10) of SOX family that were significantly dis-regulated in common among four PCa specimens. Consistent with the results of the microarray, differential mRNA and protein levels of three selected genes were found in PCa tissues by QRT-PCR analysis and immunohistochemistry. Additionally, we found that the immunohistochemical staining scores of SOX7 in PCa tissues with higher serum PSA level (P = 0.02) and metastasis (P = 0.03) were significantly lower than those with lower serum PSA level and without metastasis; the increased SOX9 protein expression was frequently found in PCa tissues with higher Gleason score (P = 0.02) and higher clinical stage (P < 0.0001); the down-regulation of SOX10 tend to be found in PCa tissues with higher serum PSA levels (P = 0.03) and advanced pathological stage (P = 0.01). Moreover, both univariate and multivariate analyses showed that the down-regulation of SOX7 and the up-regulation of SOX9 were independent predictors of shorter biochemical recurrence-free survival. Furthermore, we discovered that SOX7 was significantly down-regulated and SOX9 was significantly up-regulated during the progression to castration resistance. CONCLUSIONS: Our data offer the convince evidence that the dis-regulation of SOX7, SOX9 and SOX10 may be associated with the aggressive progression of PCa. SOX7 and SOX9 may be potential markers for prognosis in PCa patients. Interestingly, the down-regulation of SOX7 and the up-regulation of SOX9 may be important mechanisms for castration-resistant progression of PCa.

MicroRNA-23b downregulates peroxiredoxin III in human prostate cancer.

To investigate the mechanism by which peroxiredoxin III (PRDX3) is altered in human prostate cancer (PCa), we used microRNA (miRNA) target prediction program and miRNA microarray to predict and identify miR-23b as a candidate miRNA that targets PRDX3. We showed that miR-23b suppresses PRDX3 protein expression in human DU145 cells under normal and hypoxic conditions. Additionally, the clinical significance of miR-23b and PRDX3 expression in PCa patients was also confirmed. In conclusion, our data suggest that the effects of PRDX3 in PCa progression may be caused by the regulation function of miR-23b, and consequently, miR-23b may be involved in the response of PCa cells to hypoxia stress.

Extracellular matrix metalloproteinase inducer: a novel poor prognostic marker for human seminomas.

OBJECTIVE: Extracellular matrix metalloproteinase inducer (EMMPRIN) is a glycosylated member of the immunoglobulin superfamily whose function in human seminomas is unknown. We have recently determined that EMMPRIN possesses the ability to stimulate fibroblast and endothelial cell matrix metalloproteinase production, and that its expression was frequently up-regulated in several tumours of the urinary system. Thus, EMMPRIN expression might be associated with the progression of human seminomas. The aim of this study was to investigate whether the presence of EMMPRIN in seminoma tissues might help to predict the patients' prognosis. METHODS: Paraffin-embedded tissues from 65 patients with seminomas and 20 normal testes were processed for immunohistochemical staining using a mouse monoclonal antibody generated against human EMMPRIN, as primary antibody, and a biotinylated goat-anti-mouse IgG, as secondary antibody. In addition, the correlation of EMMPRIN expression with clinicopathologic characteristics and patients' prognosis was also analysed. RESULTS: EMMPRIN was detected in cancerous tissues of 53 patients with seminoma, but not normal testes. Thirty- five patients showed weakly to moderately positive and 18 patients intensely positive expression. Moreover, positive EMMPRIN staining correlated significantly with various clinicopathological factors (increased TNM stage and higher histological differentiation type) as well as decreased tumour-specific survival (log-rank, p=0.02). In particular, EMMPRIN expression was an independent prognosticator as shown by Cox regression analysis (p<0.001). CONCLUSION: EMMPRIN expression in a primary tumour predicts an unfavourable prognosis in human seminoma, suggesting its crucial role in the progression of this tumour.

Identification of novel serological tumor markers for human prostate cancer using integrative transcriptome and proteome analysis.

The aim of this study was to identify novel serological tumor markers for human prostate cancer (PCa). We compared the gene expression profile of PCa tissues to adjacent benign tissues of prostate using gene expression microarray. 1207 genes that were consistently different from adjacent benign tissues of prostate (paired t test, P<0.05) were selected as differentially expressed genes (DEGs). Among them, 652 DEGs were upregulated in PCa, whereas 555 DEGs were downregulated in PCa. In addition, two-dimensional fluorescence difference gel electrophoresis (2D-DIGE) coupled with MS was performed to screen for candidate markers in the proteome of PCa and adjacent benign tissues of prostate. A total of 89 spots were significantly up-regulated (ratio≥2, P<0.01) in PCa samples, whereas 66 spots were down-regulated (ratio≤-2, P<0.01). Sixty gene products were identified among these spots. Moreover, 14 potential candidate markers, which were identified as differentially expressed molecules by both gene expression microarray and 2D-DIGE, were chosen for validation and analysis by ELISA. The serum levels of three proteins correlated well with the 2D-DIGE results. Furthermore, the increased serum level of Inosine monophosphate dehydrogenase II (IMPDH2) was significantly associated with the clinicopathological features of the patients with PCa, suggesting its potential as a serological tumor marker. These results demonstrated that integrative transcriptome and proteome analysis could be a powerful tool for marker discovery in PCa. We suggest IMPDH2 as a novel serological tumor marker for detection of early PCa and evaluation of tumor progression.

Expression of CD147 is associated with prostate cancer progression.

Novel molecular markers that are associated with prostate cancer (PCa) progression will provide valuable information in the diagnosis and treatment of the disease. Extracellular matrix metalloproteinase inducer (CD147) has been demonstrated to be involved in tumor invasion, metastasis, growth and survival. In our study, we examined whether the expression of CD147 can be used as a prognostic marker for predicting PCa progression. Tissue samples from 240 patients who received radical prostatectomy for PCa were obtained. CD147 expression in these samples was evaluated using immunohistochemical staining with a monoclonal antibody specifically against CD147. Increased expression of CD147 was correlated with higher Gleason scores (GS), positive surgical margin, prostate-specific antigen (PSA) failure, metastasis and reduced overall survival. Both univariate Cox regression analysis and multivariate analysis including competing biological variables demonstrated that increased CD147 expression was associated with increased risk for reduced PSA failure-free, metastasis-free and overall survival. Kaplan-Meier survival curves showed that the CD147 overexpression was a significant predictor for the PSA failure-free, metastasis-free and the overall survival in both pT2 and pT3 PCa patients. More significantly, higher expression of CD147 can serve as an independent prognostic predictor for PSA failure-free survival in PCa patients when they are stratified by GS. Our study results demonstrate the involvement of CD147 in PCa progression and suggest its potential role as an independent predictor of biochemical recurrence, development of metastasis and reduced overall survival in PCa.

Expression of hedgehog pathway components is associated with bladder cancer progression and clinical outcome.

Hedgehog (Hh) pathway has been implicated in the tumorigenesis of a large number of human tumors. But its effects on the progression and prognosis of bladder cancer remain poorly understood. The aim of this study was to investigate expression patterns of Hh pathway components in bladder cancer and to elucidate their prognostic values in this tumor. The expression of sonic hedgehog (Shh), its receptor Patched (Ptch1), and downstream transcription factor Gli1 in 118 specimens of bladder cancer and 30 specimens of adjacent normal bladder tissue was determined by immunohistochemistry. Statistical analyses were applied to test the relationship between the expression of these three proteins and clinicopathologic features and prognosis. Immunohistochemical staining results showed the localizations of Shh and Ptch1 proteins to be mainly located in the cytoplasm of bladder cancer cells, whereas Gli1 was mainly localized in the nuclear of tumor cells. Additionally, positive expression of Shh, Ptch1 and Gli1 proteins was correlated with pathological stage (P = 0.006, 0.006 and 0.008, respectively), venous invasion (P = 0.01, 0.01 and 0.012, respectively) and lymph node metastasis (P = 0.009, 0.01 and 0.013, respectively), but not with other factors including age, gender, tumor grade and recurrence of superficial cancer. Moreover, patients with positive expression of Shh, Ptch1 and Gli1 proteins respectively showed poorer disease-free (P = 0.002, 0.002 and 0.001, respectively) and overall survival (all P < 0.001) than those with negative expression of these three proteins. Univariate and multivariate analysis of prognostic factors in bladder cancer patients indicated that the expression patterns of Shh, Ptch1 and Gli1 proteins were independent unfavorable prognostic factors (all P < 0.001). This is the first report describing about the correlation between Hh pathway and the prognosis of bladder cancer. Expression of Shh, Ptch1 and Gli1 proteins was greater in bladder cancers than in the adjacent normal tissues. The examination of their expression is potentially valuable in prognostic evaluation of bladder cancer.

Classical and alternative nuclear factor-κB pathways: a comparison among normal prostate, benign prostate hyperplasia and prostate cancer.

Nuclear factor-κB (NF-κB) is controlled by the classical and alternative NF-κB pathways, the role of which in prostate cancer (PCa) is not clearly defined. To provide this missing translational link, we compared the classical and alternative NF-κB pathways in normal prostate, benign prostate hyperplasia (BPH) and PCa. Prostate specimens were divided into three groups: group A, PCa (n = 68); group B, BPH (n = 60); and group C, normal prostates (n = 15). The gene expression levels of NF-κB1 and NF-κB2 were determined by real-time quantitative RT-PCR. Additionally, we analyzed the expression and sub-cellular localization of phosphorylated P50 (p-P50) and phosphorylated P52 (p-P52) proteins by immunohistochemical staining. Furthermore, associations were made between NF-κB pathway proteins and patients' prognosis. Compared with BPH and normal prostate tissues, the expression of NF-κB1 gene was differentially down-regulated by >1.5-fold, whereas NF-κB2 gene was differentially up-regulated by >2-fold in PCa tissues. The proportion of p-P50 positive patients in group A (26.5%) was significantly lower than in group B (88.3%, p = 0.005) and C (100%, p = 0.002). The proportion of p-P52 positive patients in group A (42.6%) was significantly higher than in group B (11.7%, p = 0.009) and C (6.7%, p = 0.008). Comparison of the survival curves in group A according to p-P52 expression showed a significant difference between positive and negative patients. The p-P52 positive patients showed worse prognosis (p = 0.019). Our findings suggest for the first time that the classical and alternative NF-κB pathways have an important role in PCa. p-P52 might be a predictor of poor prognosis for PCa.

[Multicenter case-control study of the relationship between smoking and bladder cancer in China].

OBJECTIVE: To explore the relationship between smoking and bladder cancer in China. METHODS: A multicenter case-control study was conducted from September 2005 to June 2008. A total of 432 bladder cancer patients, matched with 392 control cases, received a questionnaire including the type of exposure (active vs. passive smoking), the age of beginning and/or quitting smoking, smoking amount and time and depth of smoke inhalation. RESULTS: Both active smoking and passive smoking increased the incidence of bladder cancer (P < 0.05). Bladder cancer risk increased 1.89 times in active smokers and 1.88 times in passive smokers compared to non-smokers (P < 0.05). Smoke amount and time were significantly correlated with bladder cancer risk (P < 0.05). But the age of beginning smoking did not affect the bladder cancer risk (P > 0.05). Inhaling smoke into mouth or throat was also a risk factor for bladder cancer (P < 0.05). CONCLUSION: There is a strong association between smoking and bladder cancer. Active and passive smoking, smoke amount and time, and the depth of smoke inhalation are risk factors for bladder cancer. The best way of preventing bladder cancer is never smoking.

Extracellular matrix metalloproteinase inducer expression has an impact on survival in human bladder cancer.

AIM: Extracellular matrix metalloproteinase inducer (EMMPRIN) has been shown to promote tumor invasion and metastasis via stimulating matrix metalloproteinase synthesis in neighboring fibroblasts, to enhance angiogenesis via vascular endothelial growth factor, to induce chemoresistant tumor cells via the production of hyaluronan, and to confer resistance of cancer cells to anoikis through inhibition of Bim. The purpose of this study was to investigate the expression of EMMPRIN in human primary bladder cancer and to evaluate its prognostic value. METHODS: EMMPRIN expression patterns were detected by immunohistochemistry. In order to determine its prognostic value, overall survival (OS) and progression-free survival (PFS) were evaluated using the Kaplan-Meier method, and multivariate analysis was performed using the Cox proportional hazard analysis. RESULTS: Of the 101 cases with bladder cancers, 68 (67.3%) cases were positive for EMMPRIN expression. When categorized into negative vs. positive expression, EMMPRIN was associated with the stage (p=0.006), the grade (p=0.002), carcinoma in situ (p=0.01), the recurrence (p=0.009), the progression (p=0.009), and the death (p=0.01) of patients with bladder cancer. Moreover, positive EMMPRIN expression clearly predicted poorer PFS (p=0.008) and OS (p=0.006). In the multivariate analysis, positive EMMPRIN expression was an independent prognostic factor for PFS (p=0.03) and OS (p=0.03). CONCLUSION: EMMPRIN expression was greater in bladder cancers than in the adjacent normal tissues and may be a useful prognostic marker for patients with bladder cancer.

CK20 and Ki-67 as significant prognostic factors in human bladder carcinoma.

Aberrant expression of CK20 and Ki-67 has been documented in many kinds of primary tumors and has proved useful as an ancillary diagnostic aid for those tumors. The aim of this study was to analyze the expression patterns of CK20 and Ki-67 in human bladder carcinomas (BCa) and to evaluate their clinical significance in the progression of BCa. CK20 and Ki-67 expression in BCa and normal bladder tissues were detected by immunohistochemical staining. The Spearman correlation was calculated between the expression of CK20 and Ki-67 in BCa tissues. The correlation of CK20 and Ki-67 expression with the clinicopathological characteristics and the prognosis of BCa were subsequently assessed. CK20 expression was positively expressed in 103/154 (66.9%) of BCa and 2/30 (6.67%) of normal bladder tissues, respectively. The positive expression rate of Ki-67 in BCa tissues was also significantly higher than those in normal bladder tissues (81.8 vs. 10%, p < 0.01). The Spearman analysis indicated that the expression level of CK20 has a significant positive correlation with that of Ki-67 (rs = 0.86, p = 0.02). Pathologic findings demonstrated that the intensity of CK20 and Ki-67 staining in cancerous tissues was associated significantly with tumor grades (p = 0.03, p < 0.01), distant metastasis (both p < 0.01) and TNM grades (p = 0.01, p = 0.03) of BCa. The progression-free survival of the patients with CK20 (+)/Ki-67 (+) expression was poorest (p < 0.01). The results suggest that the expression of CK20 and Ki-67 may be an important feature of BCa, and the detection of their co-expression may benefit the prediction of BCa prognosis.