Hirofumi Kishi

Epigenetic inactivation of wnt inhibitory factor-1 plays an important role in bladder cancer through aberrant canonical Wnt/β-catenin signaling pathway

Purpose: Aberrant activation of the Wingless-type (Wnt) pathway plays a significant role in the pathogenesis of several human cancers. Wnt inhibitory factor-1 (Wif-1) was identified as one of the secreted antagonists that can bind Wnt protein. We hypothesize that Wif-1 plays an important role in bladder cancer pathogenesis. Experimental Design: To test this hypothesis, epigenetic and genetic pathways involved in the Wif-1 gene modulation and expression of Wnt/β-catenin-related genes were analyzed in 4 bladder tumor cell lines and 54 bladder tumor and matched normal bladder mucosa. Results: Wif-1 mRNA expression was significantly enhanced after 5-aza-2′-deoxycytidine treatment in bladder tumor cell lines. Wif-1 promoter methylation level was significantly higher and Wif-1 mRNA expression was significantly lower in bladder tumor samples than in bladder mucosa samples. In the total bladder tumor and bladder mucosa samples, an inverse correlation was found between promoter methylation and Wif-1 mRNA transcript levels. However, loss-of-heterozygosity at chromosome 12q14.3 close to the Wif-1 gene loci was a rare event (3.7%). Nuclear accumulation of β-catenin was significantly more frequent in bladder tumor than in bladder mucosa and inversely correlated with Wif-1 expression. In addition, known targets of the canonical Wnt/β-catenin signaling pathway, such as c-myc and cyclin D1, were up-regulated in bladder tumor compared with bladder mucosa, and this up-regulation was associated with reduced Wif-1 expression at both mRNA and protein levels. Furthermore, transfection of Wif-1 small interfering RNA into bladder tumor cells expressing Wif-1 mRNA transcripts had increased levels of c-myc and cyclin D1 and accelerated cell growth. Conclusion: This is the first report showing that CpG hypermethylation of the Wif-1 promoter is a frequent event in bladder tumor and may contribute to pathogenesis of bladder cancer through aberrant canonical Wnt/β-catenin signaling pathway. The present study elucidates novel pathways that are involved in the pathogenesis of bladder cancer.

COMBINATION CHEMOTHERAPY WITH PACLITAXEL, ESTRAMUSTINE AND CARBOPLATIN FOR HORMONE REFRACTORY PROSTATE CANCER

PURPOSE The activity of estramustine phosphate is synergistic with paclitaxel against hormone refractory prostate cancer. Moreover, the single agent activity of carboplatin has demonstrated a 17% response rate in measurable disease. Therefore, we conducted a prospective trial to establish more effective chemotherapy consisting of paclitaxel, estramustine phosphate and carboplatin for hormone refractory prostate cancer. MATERIALS AND METHODS The study included 32 patients with hormone refractory prostate cancer. Prior chemotherapy was accepted. Patients were treated with 100 mg./m.2 paclitaxel intravenously weekly, 10 mg./kg. estramustine phosphate orally daily and carboplatin intravenously to an area under the curve of 6 on day 1 of every 4-week cycle. Treatment was continued until disease progression or excessive toxicity. RESULTS Of the 32 patients 30 were assessable for response. A median of 7 consecutive cycles was administered per patient. Ten patients had received prior cytotoxic chemotherapy. Levels of prostate specific antigen decreased by greater than 50% in 100% of patients and by greater than 90% in 56.7%. Partial response was obtained in 61.1% of measurable lesions. Consumption of medication for cancer induced pain was reduced in 89.5% of patients. Tumor volume reduction and/or antitumor therapeutic effects were exhibited in 81.0% of patients with positive biopsy. At a median followup of 48 weeks median time to progression was 48 weeks and median overall survival was 95 weeks. Two patients suffered myocardial infarction and hepatic insufficiency, respectively, and discontinued treatment during the first cycle. Major toxicities were grade 3 or 4 anemia in 59.4% of patients, leukopenia in 37.5%, thrombocytopenia in 28.1% and neuropathy in 12.5%. However, all toxicity was temporary and reversible with dose reduction or temporary cessation of chemotherapeutic agents. CONCLUSIONS Paclitaxel, estramustine phosphate and carboplatin chemotherapy was extremely effective for hormone refractory prostate cancer. Although hematological and neurotoxicity were modest, this therapy may be more manageable with lower doses.

Neoadjuvant Chemotherapy for Locally Advanced Urothelial Cancer of the Upper Urinary Tract

Cisplatin-based multiple-drug chemotherapy is currently considered the most effective treatment for advanced and metastatic urothelial cancers. We treated 15 patients with locally advanced urothelial cancers of the upper urinary tract using the cisplatin-based multiple-drug regimen in a neoadjuvant setting. The regimens administered were: M-VAC (methotrexate, vinblastine, doxorubicin and cisplatin); MEC (methotrexate, etoposide and cisplatin), or M-VEC (methotrexate, vinblastine, epirubicin and cisplatin). Total nephroureterectomy was performed in all patients and response was evaluated pathologically Of 15 patients 2 (13%) achieved a pathological complete response, 6 (40%) a pathological partial response, for an overall response rate of 53% (95% confidence limits 29-77%). The median durations of response were 54 months for patients with a pathological complete response and 15.5 months for patients with a pathological partial response. One of six patients with a pathological partial response and 4 of 7 with no remission died of cancer. While a positive relationship between the pathological response and prognosis was observed, adequate follow-up is needed to assess the ability of neoadjuvant chemotherapy to improve the prognosis of patients with locally advanced urothelial cancer of the upper urinary tract.

CpG methylation at promoter site −140 inactivates TGFβ2 receptor gene in prostate cancer

The action of transforming growth factor β (TGF‐β) is mediated through type 1 (TβRI) and type 2 (TβRII) receptors. Prostate cancer cells are often resistant to TGF‐β signaling due to loss of TβRII expression. The authors of the current study hypothesized that CpG methylation of the TβRII promoter at the Sp1 binding site −140 mediates this loss of TβRII expression in prostate cancer.

Traumatic rhabdomyolysis resulting from continuous compression in the exaggerated lithotomy position for radical perineal prostatectomy

Abstract This report demonstrates a case of rhabdomyolysis as a result of the exaggerated lithotomy position during radical perineal prostatectomy. The pathogenesis, diagnosis, management, and preventive measures of rhabdomyolysis are also reviewed.

Blockade of Paclitaxel-Induced Thymidine Phosphorylase Expression Can Accelerate Apoptosis in Human Prostate Cancer Cells

Recently, survival benefit by chemotherapy using paclitaxel (PTX) and the induction of thymidine phosphorylase (TP) by PTX have been reported in several solid tumors. On the other hand, TP confers antiapoptotic effect on tumor cells through inhibition of caspase-8 activation in vitro. On the basis of these previous observations, we hypothesized that (a) TP can be induced after PTX treatment in human prostate cancer (PC) and (b) blockade of PTX-induced TP expression can enhance the apoptotic processes in human PC cells. PTX was used to find TP expression in all eight hormone-refractory PC cases after chemotherapy; however, cleaved caspase-8 was not expressed after chemotherapy in the six hormone-refractory PC cases with strong TP expression. In PC cell lines (PC-3, DU 145, and LNCaP), TP expression after PTX treatment was clearly up-regulated in a dose-dependent manner. Cell viability of PC cell lines treated with PTX and TP antisense was significantly reduced in a time-dependent and dose-dependent manner compared with the PTX treatment alone. Likewise, apoptotic index of PC cells treated with PTX and TP antisense was significantly increased in comparison with PTX alone. After complete blockade of PTX-induced TP translation by TP antisense transfection, cleaved form of caspase-3 and poly(ADP-ribose) polymerase was increased, and this exaggeration of apoptosis also ran parallel with caspase-8 activation in a PTX dose-dependent manner. However, in PC cell lines treated with TP antisense alone, neither caspase-3 nor poly(ADP-ribose) polymerase was cleaved despite caspase-8 activation. These results indicate that PTX-induced TP up-regulation is associated with decreased caspase-8 activation. This study is the first report showing that blockade of PTX-induced TP expression could exaggerate the processing of apoptosis in PC cells treated with PTX. Our results provide preclinical evidence that TP could be a new molecular target for enhancing the potency of PTX-mediated apoptosis in PC cells.

Clinical Value of Argyrophilic Organizer Region in Bladder Transitional Cell Carcinoma

For the purpose of elucidating whether or not argyrophilic organizer regions (AgNORs) predict the biological behaviors of bladder tumors, the AgNOR was analyzed in 80 primary bladder transitional cell carcinomas (TCCs), using the computer-assisted image analyzer. The AgNOR parameters used were the mean AgNOR count (C-AgNOR) and the percentage of cells exhibiting more than 3 AgNOR dots or 4 AgNOR dots within nuclei (3P-AgNOR and 4P-AgNOR, respectively). The correlation of C-AgNOR with 3P-AgNOR and 4P-AgNOR reached a high statistical significance (p < 0.0001, respectively). All of these three AgNOR parameters correlated with histological grade, whereas the difference between grade I and II proved to be higher in 3P-AgNOR and in 4P-AgNOR (p < 0.01, respectively) as compared with that in C-AgNOR (p < 0.05). Similarly, these three parameters correlated with histological stage, whereas the statistical significance of the correlation was less prominent in C-AgNOR. Moreover, the prognostic relevance was noted in C-AgNOR (p = 0.041), whereas it was indicative in 3P-AgNOR as well as in 4P-AgNOR (p = 0.090 and p = 0.061, respectively). These results suggest that 3P-AgNOR and 4P-AgNOR reflect the difference in the proliferative activity of individual TCCs more precisely than C-AgNOR. Since the biological behaviors of individual TCCs cannot be predicted by the proliferative activity alone, the AgNOR in TCCs has a rather limited value regarding the prediction of survival.

MP48-12 EXTRAORDINARY ELEVATION OF SERPINB2 GENE AFTER ANTI-CANCER DRUG TREATMENT IN BLADDER CANCER

of morphine on bladder cancer cell growth in vitro and examined whether those effects can be reversed with receptor blockers. METHODS: Cell lines: Adherent epithelial cell lines were used:RT-112 Human urinary bladder transitional carcinoma cell lines, histological grade G2 (moderately differentiated). PNT2 Normal (virally transformed) Human prostate epithelial cell line. These cells were grown using routine cell culture techniques supplemented with 10% foetal calf serum and antibiotics. Proliferation assay: The assay recorded residual viable biomass (RVB) 72 hours into exposure with the agent being studied RESULTS: Doubling dilution of morphine produced a bell-shaped curve, with high (non-clinical)concentrations inhibiting growth, followed by stimulation between 100 and 1 microgram per ml (clinically relevant concentrations shown in Figure 1 green circle), reverting to control levels thereafter. The near-normal PNT-2 cell line showed minimal responsiveness to morphine Incubation with naloxone alone has little effect on residual biomass compared to controls Conversely, pre-incubating with a fixed concentration of Naloxone, then titrating morphine across the plate showed stimulation to decrease as the relative proportion of blocker rises (Figure 2) CONCLUSIONS: Morphine in clinically relevant concentrations stimulated growth in the RT-112 transitional carcinoma cell line, as assessed by the MTT assay. This effect was minimal under the same conditions using the virally transformed normal prostate cell line (PNT2). Treating cells with the antagonists Naloxone or Naltrexone inhibited the action of morphine. The tentative implication is that using opioids in cancer patients despite their important role in pain relief may also tend to promote tumour growth.

MP38-20 METABOLIC DIFFERENCE IDENTIFIED BY PROTON MR-SPECTROSCOPY IS ASSOCIATED WITH INTRA-TUMOR HETEROGENEITY IN PROSTATE CANCER

25.5% had Gleason 6, 25.5% had Gleason 7, and 9.0%, had Gleason 810 on final histopathology. Fusion Biopsy of PIRADSv2 3 lesions (n1⁄466) revealed no cancer in 65.2%, Gleason 6 in 15.2%, Gleason 7 in 19.7% and Gleason 8-10,in 0% of patients. Of 83 patients with clinically significant cancer, 26 (31.3%) would have been missed on standard biopsy and 12 (14.5%) would have been missed using fusion biopsy alone. Concordance between both biopsy modalities was 63.1%. CONCLUSIONS: mp-MRI targeted fusion biopsy improves the detection of clinically significant prostate cancer in select patients. However, our results demonstrate that a significant proportion of these cancers will not be detected by a targeted biopsy alone. Therefore, standard template biopsies should remain an integral component of any fusion biopsy program.

Usefulness of an immunochromatographical assay, PSA Rapid Test as a primary screening test for prostate cancer

BackgroundThe recent rapid increase of mass screening for prostate cancer by measuring PSA in Japan will increase the economic burden to the healthcare system. PSA Rapid Test (PRT) is a simple inexpensive test. The usefulness of PRT as a primary screening test for prostate cancer was evaluated.MethodsWhen we conducted educational lectures for prostate cancer in our city, screening for prostate cancer using PRT was offered to the male participants. The results of the tests were handed to participants in writing at the end of the lectures. When the results were judged as positive, letters of referral to our institute were enclosed.ResultsOne hundred and fourteen (18.6%) of 614 men were judged as positive by PRT. Of the 114 men with positive PRT, 73 (64%) visited our institution. Finally, 37 men underwent a transrectal prostate biopsy and a diagnosis of prostate cancer was made in 21 men (3.4% of all participants). The total costs for the PSA tests in this study were summed to be approximately