Background/aims. We have reported that tubular epithelial cell injury caused by renal ischemia−reperfusion is attenuated in conditional VHL knockout (VHL-KO) mice and also that induction of hypoxia-inducible factor (HIF) suppresses angiotensin II-accelerated Habu snake venom (HV) glomerulonephropathy in rats. However, it remains unknown whether VHL knockdown protects glomerular endothelial cells from endothelium-targeted glomerulonephritis. Methods and results.VHL-KO mice with HV glomerulonephropathy (HV GN) had fewer injured glomeruli, a lower mesangiolysis score and reduced blood urea nitrogen levels. Immunoreactivity of vascular endothelial growth factor (VEGF) in the glomerular capillaries was enhanced by VHL knockdown and was conserved even in VHL-KO mice with HV GN, despite HV-attenuating endothelial VEGF expression in vitro . VHL-KO mice showed enhanced nitric oxide (NO) production in glomerular endothelial cells and tubular cells, associated with activated VEGF expression in the kidney (i.e. an activated NO–VEGF axis). The levels of NO in glomeruli and tubules were conserved even in mice with HV GN. In contrast, suppressing NO production in glomerular endothelial cells by an NO synthase inhibitor, Nϖ -nitro- L -arginase, completely blunted the protection of VHL-KO from HV GN. The activated NO-VEGF axis in the kidney of VHL-KO mice was also associated with an elevation in Flk-1 phosphorylation and increased levels of IL-10 and IP-10. Conclusion. Conditional VHL knockdown may enhance the NO–VEGF axis and protect glomerular endothelial cells from HV GN, thereby providing resistance to injury of tubular epithelial cells and glomerular endothelial cells.
We describe a 75-year-old man with undifferentiated prostate cancer that was treated with radiation therapy. He presented at a nearby general hospital with dysuria and pain upon micturition. He was diagnosed with undifferentiated prostate cancer by a needle biopsy and referred to our hospital for further examination and treatment. Enhanced computed tomography and magnetic resonance images showed prostate cancer and right obturator lymph node metastasis measuring 2.5 cm. Cystoscopy and colonoscopy revealed direct invasion of the urinary bladder and rectum. We constructed a vesical fistula and an artificial anus, and then treated the primary tumor and lymph node metastasis with radiation. Undifferentiated prostate cancer is extremely rare and to our knowledge only a few cases have been reported. We suggest that radiation might be effective for treating undifferentiated prostate cancer with or without local invasion and/or metastasis along with total body control.
Allelic losses within several tumor suppressor genes have been detected frequently in various types of human cancer. We investigated the roles and possible interactions of the tumor suppressor genes p53, Rb, DCC and APC in bladder cancer.Loss of heterozygosity (LOH) of these 4 genes was examined in 45 human bladder cancers by polymerase chain reaction and restriction fragment length polymorphism assay.Of the evaluated cases, LOH was seen at P53 in 38%, at Rb in 22%, at DCC in 36% and at APC in 6% of tumors. Loss of heterozygosity at p53 and Rb was predominantly observed in high grade (grade 3) and/or invasive (T2 or greater) tumors, whereas LOH at DCC was present irrespective of tumor grade and stage. Allelic losses at either p53, Rb, DCC or APC were seen in 82% of high grade tumors, but in only 21% of low grade (grade 1 and 2) tumors (p<0.005). Similarly, 71% of invasive tumors had LOH at one or more loci compared with 20% of superficial (Ta and T1) tumors (p<0.005). Interestingly, p53-LOH and Rb-LOH were often observed simultaneously in the same tumor.These results suggest that loss of the p53, Rb and/or DCC genes is involved in most of the late and some of the early steps of bladder carcinogenesis.
Through genome-wide expression profile analysis, hypoxia-inducible protein 2 (HIG2) has previously been identified as an oncoprotein involved in development/progression of renal cell carcinoma (RCC). We subsequently identified a highly immunogenic HLA-A*0201/0206-restricted epitope peptide (HIG2-9-4) corresponding to a part of HIG2 and applied it as a therapeutic vaccine. We conducted a phase I clinical trial using the HIG2-9-4 peptide for patients with advanced RCC. Nine patients having HLA-A*0201 or HLA-A*0206 with metastatic or unresectable RCC after failure of the cytokine and/or tyrosine kinase inhibitor therapies were enrolled in this study. The patients received subcutaneous administration of the peptide as an emulsion form with Montanide ISA-51 VG once a week in a dose-escalation manner (doses of 0.5, 1.0, or 3.0 mg/body, 3 patients for each dose). The primary endpoint was safety, and the secondary endpoints were immunological and clinical responses. Vaccinations with HIG2-9-4 peptide could be well tolerated without any serious systemic adverse events. Peptide-specific cytotoxic T lymphocyte (CTL) responses were detected in eight of the nine patients. Doses of 1.0 or 3.0 mg/body seemed to induce a CTL response better than did a dose of 0.5 mg/body, although the number of patients was too small to draw a firm conclusion. The disease control rate (stable disease for ≥4 months) was 77.8 %, and the median progression-free survival time was 10.3 months. HIG2-9-4 peptide vaccine treatment was tolerable and effectively induced peptide-specific CTLs in RCC patients. This novel peptide vaccine therapy for RCC is promising.
The combination therapy of urinary bladder cancer with radiation and hyperthermia with bleomycin was investigated. Immediately following daily external irradiation (40 Gy/4 weeks), patients were irrigated with a solution of warmed saline (intravesical temperature, 42–43°C) containing 30 μg/ml bleomycin. Of a total of 56 patients, complete responses were observed in 25, and partial responses in 21. Among T2-T3 cases, an 84% response rate was noted in combination therapy, whereas a 56% response rate was observed after radiation alone (50–70 Gy). The side-effects of the combination therapy were limited to reversible bladder irritation, and bladder capacity could be maintained within normal limits. These results suggest that combination therapy represents an effective conservative therapy for the management of bladder cancer.
Hemangioblastoma is one of the benign tumors in the central nervous system. It is often associated with the von Hippel-Lindau (VHL) disease, a well known hereditary tumor syndrome. It is believed that inactivation of both alleles of VHL tumor suppressor gene is essential in the tumorigenic processes in hemangioblastomas associated with VHL disease. The molecular basis for the development of sporadic hemangioblastomas is not known. Here, we analyzed 13 cases of primary sporadic hemangioblastomas for somatic mutations of VHL gene with single strand conformational polymorphism analyses of the tumor DNAs. We detected abnormal single strand conformational polymorphism pattern in 7 tumors (54%). Of these 7 possibly mutated tumors, we successfully characterized 3 tumors by direct sequencing. We were unable to sequence 4 tumors because of the poor quality of DNA obtained from paraffin blocks. Somatic mutations in the 3 tumors were 2 missense mutations and 1 microdeletion. These mutations were observed in 1 tumor in exon 1 and 2 tumors in exon 2. Our results suggest that mutations of VHL tumor suppressor gene are involved in the development of at least 20% of sporadic central nervous system hemangioblastomas.
To enhance the convenience and reduce the cost of prostate cancer (PC) screening, a one-step prostate-specific antigen (PSA) test was evaluated in a large population. The PSA SPOT test kit enables rapid detection of human PSA in serum or plasma at or above a cutoff level of 4 ng/mL to aid in the diagnosis of PC.PC screening using the PSA SPOT test was offered to male participants in educational public lectures that we conducted in various cities. Test results were reported to participants at the end of the lectures. Blood samples from 1429 men were evaluated. Two independent observers interpreted the tests at 15 and 30 min. The remaining serum samples were subsequently tested using a conventional quantitative assay.The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the test were 79.9, 93.0, 65.4, 96.6, and 91.2%, respectively. The sensitivity and specificity of the test changed with variations in the reading time. Quantitative assessment of the intensity of the band was correlated with the PSA value.PSA testing using this kit can be easily performed. The low cost and speed of the test make it a useful and convenient tool for primary PC screening.
Renal oncocytomas and chromophobe renal cell carcinomas (RCCs) share a common phenotype and both originate from the intercalated cells of the collecting duct. This makes it very difficult to differentiate between the two tumors immunohistochemically. Therefore, we studied the results of immunohistochemistry focusing on certain characteristic structures that are occasionally present in renal oncocytomas. We carried out Hale's colloidal iron staining and immunohistochemistry for various cytokeratins (cytokeratins 7, 8, 10, 10/13, 14, 18, 19 and 20, and AE1/AE3) in four oncocytomas and six chromophobe RCCs. In addition, one renal oncocytoma and one chromophobe RCC were studied using electron microscopy. Two renal oncocytomas and one chromophobe RCC were completely unstained by colloidal iron. There was no evident difference between the immunohistochemical characteristics of oncocytomas and those of chromophobe RCCs. However, in all four renal oncocytomas we identified intracytoplasmic ring-like positive reactions for some cytokeratins (at least 3 antigens of cytokeratins 7, 8 and 19, and AE1/AE3), which corresponded ultrastructurally to the intracytoplasmic lumens (ICLs). In contrast, no such structures were found in any of the chromophobe RCCs using the antibodies employed. Therefore, immunohistochemical identification of ICLs by cytokeratin typing may be useful for differentiating between renal oncocytomas and chromophobe RCCs and be more sensitive in this respect than colloidal iron staining.
