Matriptase-Induced Phosphorylation of MET is Significantly Associated with Poor Prognosis in Invasive Bladder Cancer; an Immunohistochemical Analysis.

Hepatocyte growth factor (HGF) plays an important role in cancer progression via phosphorylation of MET (c-met proto-oncogene product, receptor of HGF). HGF-zymogen (pro-HGF) must be processed for activation by HGF activators including matriptase, which is a type II transmembrane serine protease and the most efficient activator. The enzymatic activity is tightly regulated by HGF activator inhibitors (HAIs). Dysregulated pro-HGF activation (with upregulated MET phosphorylation) is reported to promote cancer progression in various cancers. We retrospectively analyzed the expression of matriptase, phosphorylated-MET (phospho-MET) and HAI-1 in tumor specimens obtained from patients with invasive bladder cancer by immunohistochemistry. High expression of phospho-MET and increased expression of matriptase were significantly associated with poor prognosis, and high matriptase/low HAI-1 expression showed poorer prognosis. Furthermore, high expression of matriptase tended to correlate with phosphorylation of MET. Increased expression of matriptase may induce the ligand-dependent activation of MET, which leads to poor prognosis in patients with invasive bladder cancer.

[Effectiveness of acupuncture and moxibustion therapy for the treatment of refractory interstitial cystitis].

The efficacy of acupuncture and moxibustion treatment was examined on eight female patients with refractory interstitial cystitis (IC) who had been treated conservatively with hydrodistension, intravesical instillation of dimethyl sulfoxide, or oral medication. These patients had received hydrodistension on an average of 2.3±1.8 times. Moxa needles were applied to Ciliao in bladder meridian 32 and Xialiao in bladder meridian 34, and electroacupuncture was performed on Zhongliao in bladder meridian 33 at 3 Hz for 20 min once a week. The bladder condition was assessed by the visual analogue scale (VAS) score, the O'Leary-Sant Interstitial Cystitis Symptom Index (ICSI), the Interstitial Cystitis Problem Index (ICPI), and the maximum voided volume (MVV). After 3 months, patients who showed a reduction of >2 in their VAS score, reduction of <30% of ICSI and ICPI, and increase of >100 ml MVV were considered responders. There were three responders, and after repeated therapy to maintain these effects, they no longer required hydrodistension. Two responders had no recurrence for 48 months or more. Acupuncture and moxibustion resulted in improvement in 38% of the patients (3/8) with refractory IC, and repeated therapy maintained the therapeutic effects. This therapy is traditional and relatively noninvasive. Although its precise mechanism of action is unclear, this study suggests that acupuncture and moxibustion treatment may be a complementary and alternative therapeutic option for refractory IC.

Identification of the α2 chain of interleukin-13 receptor as a potential biomarker for predicting castration resistance of prostate cancer using patient-derived xenograft models.

BACKGROUND: Several treatment strategies use upfront chemotherapy or androgen receptor axis-targeting therapies for metastatic prostate cancer. However, there are no useful biomarkers for selecting appropriate patients who urgently require these treatments. METHODS: Novel patient-derived xenograft (PDX) castration-sensitive and -resistant models were established and gene expression patterns were comprehensively compared. The function of a gene highly expressed in the castration-resistant models was evaluated by its overexpression in LNCaP prostate cancer cells. Protein expression in the tumors and serum of patients was examined by immunohistochemistry and ELISA, and correlations with castration resistance were analyzed. RESULTS: Expression of the α2 chain of interleukin-13 receptor (IL13Rα2) was higher in castration-resistant PDX tumors. LNCaP cells overexpressing IL13Rα2 acquired castration resistance in vitro and in vivo. In tissue samples, IL13Rα2 expression levels were significantly associated with castration-resistant progression (p < 0.05). In serum samples, IL13Rα2 levels could be measured in 5 of 28 (18%) castration-resistant prostate cancer patients. CONCLUSION: IL13Rα2 was highly expressed in castration-resistant prostate cancer PDX models and was associated with the castration resistance of prostate cancer cells. It might be a potential tissue and serum biomarker for predicting castration resistance in prostate cancer patients.

Expression of protease activating receptor-2 (PAR-2) is positively correlated with the recurrence of non-muscle invasive bladder cancer: an immunohistochemical analysis.

Background: Matriptase, which is a Type II transmembrane serine protease, has the potential to activate several growth factors, including pro-hepatocyte growth factor (HGF). A G protein-coupled transmembrane cell-surface receptor and a protease-activated receptor 2 (PAR-2) are also required for activation by matriptase. Activation of PAR-2 has been reported to induce the progression of various cancers. In a previous study, we evaluated the correlation between upregulation of MET phosphorylation with high matriptase expression and worse prognosis in patients with muscle invasive bladder cancer; however, expression of PAR-2, matriptase and MET in non-muscle invasive bladder cancer (NMIBC) has not been evaluated. Materials and methods: We retrospectively analyzed the expression of PAR-2, matriptase and MET using 55 paraffin-embedded specimens obtained from patients with NMIBC by immunohistochemistry. Results: MET was significantly expressed in high-grade urothelial carcinoma (UC) and pathological T1 cancers. High expression of PAR-2 was significantly associated with a worse recurrence rate in NMIBC. In subgroup analysis, the expression of PAR-2 was also correlated with high recurrence rate in low-grade UC. In addition, expression of matriptase tended to correlate with worse recurrence rate in high-grade UC. Conclusion: Increased expression of PAR-2 was significantly correlated with worse recurrence rate in patients with NMIBC. In addition, expression of matriptase also indicated a tendency toward recurrence in high-grade UC, suggesting an important role of matriptase-induced PAR-2 activation in NMIBC.

Caveolin-1 and -2 regulate cell motility in castration-resistant prostate cancer.

BACKGROUND: Caveolin (Cav)-1 and Cav-2 are cell membrane proteins, which are structural proteins of caveolae and are reported to be positive regulators of cell survival and metastasis in prostate cancer (PC). In a previous study, we reported that elevated levels of Cav-1 and Cav-2 were significantly associated with PC progression. However, their functions in PC have not yet been clarified. In this study, we examined the function of Cav-1 and Cav-2 in PC cell invasiveness and motility. MATERIALS AND METHODS: We introduced Cav-1- and Cav-2-specific small interfering into PC3 cells to knock-down (KD) both molecules. We also performed cell proliferation assay, wound healing assay, migration assay, and invasion assay using PC3 cells and compared the results between Cav-1-KD, Cav-2-KD, and negative control PC3 cells. In addition, we performed real-time quantitative PCR (RT-qPCR) and RT2 Profiler PCR Array analysis to identify factors influencing migration. RESULTS: We observed no significant difference in the proliferative and invasive activities of Cav-1-KD and Cav-2-KD PC3 cells; however, the cell motility was significantly decreased compared with negative control PC3 cells. RT-qPCR revealed that the expression of vimentin and N-cadherin was downregulated in Cav-1-KD PC3 cells. In addition, PCR array revealed a decreased expression of MGAT5, MMP13, and MYCL in Cav-1-KD PC3 and ETV4, FGFR4, and SRC in Cav-2-KD PC3. CONCLUSION: Cav-1 and Cav-2 may positively contribute to the upregulation of castration-resistant PC cell migration. Cav-induced regulation of several molecules including vimentin, N-cadherin, MGAT5, MMP13, MYCL, ETV4, FGFR4, and SRC may have an important role in PC3 cell motility. However, further examination will be required.

Dysregulated HAI-2 Plays an Important Role in Renal Cell Carcinoma Bone Metastasis through Ligand-Dependent MET Phosphorylation.

MET, a c-met proto-oncogene product and hepatocyte growth factor (HGF) receptor, is known to play an important role in cancer progression, including bone metastasis. In a previous study, we reported increased expression of MET and matriptase, a novel activator of HGF, in bone metastasis. In this study, we employed a mouse model of renal cell carcinoma (RCC) bone metastasis to clarify the significance of the HGF/MET signaling axis and the regulator of HGF activator inhibitor type-2 (HAI-2). Luciferase-transfected 786-O cells were injected into the left cardiac ventricle of mice to prepare the mouse model of bone metastasis. The formation of bone metastasis was confirmed by whole-body bioluminescent imaging, and specimens were extracted. Expression of HGF/MET-related molecules was analyzed. Based on the results, we produced HAI-2 stable knockdown 786-O cells, and analyzed invasiveness and motility. Expression of HGF and matriptase was increased in bone metastasis compared with the control, while that of HAI-2 was decreased. Furthermore, we confirmed increased phosphorylation of MET in bone metastasis. The expression of matriptase was upregulated, and both invasiveness and motility were increased significantly by knockdown of HAI-2. The significance of ligand-dependent MET activation in RCC bone metastasis is considered, and HAI-2 may be an important regulator in this system.

Matriptase and MET are prominently expressed at the site of bone metastasis in renal cell carcinoma: immunohistochemical analysis.

High MET expression in renal cell carcinoma (RCC) and MET activation in bone metastases are reportedly important in progression of several cancers. To find new treatment targets in bone metastasis, we immunohistochemically analyzed expression levels of MET and matriptase (specific cellular activator of hepatocyte growth factor). We obtained nephrectomy specimens from 17 RCC patients with metastasis, and bone metastases specimens from 7 RCC patients who underwent metastasectomies, and who were treated at our hospital between 2008 and 2012. We tested the samples with anti-human MET polyclonal antibody and anti-human matriptase polyclonal antibody, and compared postoperative overall survival (OS) rates between positive and negative groups. High MET expression was seen at primary sites in 8/17 (47%) nephrectomy specimens, and 6/7 (86%) bone specimens. Matriptase was expressed in 6/17 (35%) nephrectomy specimens, and all 7 (100%) bone specimens. Interestingly, matriptase was strongly expressed in osteoclasts of 5/7 bone specimens. Postoperative OS rate was significantly higher in the MET(-) group than the MET(+) group. The high MET and matriptase expression seen in RCC cells in bone metastasis accompanied by matriptase expression in osteoclasts indicates their importance in bone metastasis.