Hidefumi Kinoshita

Antiandrogen bicalutamide promotes tumor growth in a novel androgen-dependent prostate cancer xenograft model derived from a bicalutamide-treated patient.

Androgen ablation therapies are effective in controlling prostate cancer. Although most cancers relapse and progress despite androgen ablation, some patients experience antiandrogen withdrawal syndrome, in which those treated with antiandrogen show clinical improvement when antiandrogen is discontinued. Although the androgen receptor (AR) is suggested to play an important role in prostate cancer progression even after the androgen ablation, limited tissue availability for molecular studies and small numbers of human prostate cancer cell lines have restricted prostate cancer research. Here, we describe KUCaP, a novel serially transplantable human prostate cancer xenograft model. We established KUCaP from liver metastatic tissue of a patient treated with antiandrogen bicalutamide. KUCaP expressed the AR with a point mutation at amino acid 741 (tryptophan to cysteine; W741C) in the ligand-binding domain. This mutation was also present in cancerous tissue used for generation of KUCaP. Although the growth of KUCaP in male mice was androgen dependent, bicalutamide aberrantly promoted the growth and prostate-specific antigen production of KUCaP. For the first time, we show the agonistic effect of bicalutamide to a xenograft with clinically induced AR mutation. This bicalutamide-responsive mutant AR will serve in the development of new therapies for androgen ablation-resistant prostate cancers.

Increased risk of prostate cancer associated with AA genotype of cyclin D1 gene A870G polymorphism

CCND1 mRNA is alternatively spliced to produce 2 transcripts, and the splicing pattern may be modulated by a frequent A870G single‐nucleotide polymorphism within the conserved splice donor site of exon 4. Several studies have suggested a significant association between the CCND1 genotype and onset or progression of various cancers. To investigate the correlation of the polymorphism with genetic susceptibility to PCa and its disease status, we examined the polymorphism in 214 cases of PCa, 234 cases of BPH and 254 male controls. The CCND1 A allele was more frequently observed in the PCa group (p = 0.015) and the BPH group (p = 0.018) than the control group. Men with the AA genotype had an increased risk of PCa (aOR = 1.93, 95% CI 1.13–3.30, p = 0.016) and BPH (aOR = 1.84, 95% CI 1.09–3.09, p = 0.023) compared to those with the GG genotype. No significant association was observed when men with the AG genotype were compared to those with the GG genotype (PCa: aOR = 1.00, 95% CI 0.65–1.54, BPH: aOR = 0.91, 95% CI 0.60–1.39). The risk of PCa associated with the AA genotype appeared to be stronger in men aged 73 years or younger (aOR = 2.89, 95% CI 1.38–6.01, p = 0.005), whereas no association was found in men older than 73 years (aOR = 1.02, 95% CI 0.44–2.34). No significant difference in genotype frequency was found among patients with low‐, intermediate‐ and high‐grade tumors (p = 0.730) or between patients with localized and metastatic PCa (p = 0.679). However, in patients with high‐grade or metastatic PCa, a significantly increased risk associated with the AA genotype compared to controls was observed, while no significant results were found in those with low/intermediate or localized PCa. The A allele of the CCND1 A870G polymorphism was recessively associated with susceptibility to PCa and BPH in a Japanese population, giving a 2‐fold increased risk of PCa and BPH in men with the AA genotype compared to those with the GG genotype. Although the risk of PCa associated with the AA genotype appeared to contribute especially to men aged 73 years or younger and the A allele may be associated with disease status of PCa, these conjectures require validation in future studies on a larger number of subjects.

Allelic Frequency of p53 Gene Codon 72 Polymorphism in Urologic Cancers

Alterations in the p53 tumor suppressor gene appear to be important in the development of many human tumors. The wild‐type p53 gene has a polymorphism at codon 72 that presents the arginine (CGC) or proline (CCC) genotype, which recently has been reported to be associated with genetically determined susceptibility to smoking‐related lung cancers. To determine whether this p53 genotype influences individual risk of urologic cancer and/or its progression, we used polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) analysis to assay the allelic frequencies of this polymorphism in 85 renal cell carcinoma patients, 151 urothelial cancer patients, 33 testicular cancer patients, 28 prostatic cancer patients and 56 patients without neoplastic disease. The allelic distributions of the three genotypes (Arg/Arg, Arg/Pro, Pro/Pro) in patients with renal cell carcinoma (29.4%, 55.3%, 15.3%), urothelial cancers (45.7%, 39.7%, 14.6%), testicular cancer (45.4%, 48.5%, 6.1%) or prostate cancer (42,9%, 50.0%, 7.1%) did not differ significantly from those in the normal controls. However, Pro/Pro genotype in renal cell carcinoma and urothelial cancer (smoking‐related cancers) was more frequent than that in prostate cancer and testicular cancer (smoking‐unrelated cancers) with borderline significance (P=0.0881). There was no particular correlation between frequency of the three genotypes and grade or stage of each type of tumor. The association of genetic predisposition to urologic cancers with p53 gene codon 72 polymorphism is not so clear as the previous study of Japanese lung cancer patients, but this polymorphism may play some role in urothelial cancers and renal cell carcinoma, in which smoking is an epidemiological risk factor.

Expression Patterns Of Multidrug-Resistance (MDR1), Multidrug Resistance-Associated Protein (MRP), Glutathione-S-Transferase-pi (GST-pi) and DNA Topoisomerase II (TOPO II) Genes In Renal Cell Carcinomas And Normal Kidney

PURPOSE Expression levels of the multidrug-resistance (mdr1), multidrug resistance-associated protein (MRP), glutathione-S-transferase-pi (GST-pi) and DNA topoisomerase II (Topo II) genes in normal kidney and renal cell carcinomas were analyzed to study the complexity of the roles of these genes. MATERIALS AND METHODS The reverse transcription-polymerase chain reaction (RT-PCR) assay was used with beta 2 microglobulin (beta 2 m) as the internal control. RESULTS In normal kidneys, the expression levels of the 4 genes in individual normal kidney samples correlated significantly with one another. Comparisons of the expression levels between normal kidneys and renal cell carcinomas showed that only the mean MRP gene expression level was higher in renal cell carcinomas than in normal kidneys (p = 0.018). The expression patterns of the 4 genes in renal cell carcinomas differed markedly for nonpapillary and papillary tumors. The mean MRP/beta 2 m ratio for the papillary type was significantly lower than that for the nonpapillary alveolar type carcinoma (p = 0.004). The 4 genes showed moderate positive correlations with one another in alveolar type renal carcinoma similar to the correlations observed in normal kidneys. In contrast, in papillary type, MRP expression was inversely correlated with mdr1 and Topo II expression. CONCLUSION Differences in cytogenetic changes, origins and natural histories between papillary and nonpapillary carcinoma may be associated with these distinct expression patterns of the resistance-related genes. Further study is required to clarify whether the differences in the expression patterns between these 2 structural types of carcinoma affect their chemosensitivities and clinical outcomes.

LOW FREQUENCY OF POSITIVE TELOMERASE ACTIVITY IN A CHROMOPHOBE SUBTYPE OF RENAL CELL CARCINOMA

PURPOSE In malignant tumors, telomerase reactivation plays an important role in the acquisition of cellular immortality. We evaluated the telomerase activity in renal cell carcinomas (RCCs) with special reference to their clinicopathologic features. MATERIALS AND METHODS Telomerase activity was examined in 47 RCCs and 9 RCC cell lines by telomeric repeat amplification protocol assay (TRAP). The telomere lengths were assessed by Southern analysis of terminal restriction fragments (TRFs) generated by Hinfl-digested DNA. RESULTS Thirty-six (77%) of the 47 RCCs and all 9 RCC cell lines showed telomerase activity, whereas no activity was detected in any of 30 normal kidneys. When the tumors were histopathologically classified, only one (17%) of the 6 chromophobe cell carcinomas was telomerase-positive. This frequency was significantly low (p < 0.001) when compared with those in clear cell RCCs (93%; 26/28). In 40 of the 47 patients, DNA from the tumor tissues and the paired normal kidneys was available for analysis of the TRF lengths. No tumor showed elongated TRF length compared to its paired normal kidney. Regarding the relationship between telomere length and telomerase activity, 23 (74%) of the 31 telomerase-positive RCC and 6 (67%) of the 9 telomerase-negative RCC exhibited reduced TRF. There was no significant correlation between the telomere reduction and telomerase activity. CONCLUSION The mechanism for preventing telomere shortening may differ according to RCC subtype. Alternatively, telomerase-negative tumors may have yet to reach the immortal stage when they progress to clinical cancer. The telomerase activity status may contribute to the biological potential and the prognosis of RCCs.

Assessment of a protocol for prophylactic antibiotics to prevent perioperative infection in urological surgery: a preliminary study.

Background: The aim of the present study was to assess the usability and efficacy of our new protocol of prophylactic antibiotic use to prevent perioperative infection in urological surgery.

N-ras mutation in 7,12-dimethylbenz[a]anthracene (DMBA)-induced erythroleukemia in Long-Evans rats

Intravenous injections of 7,12-dimethylbenz[a]anthracene (DMBA) induce erythroblastic leukemia (erythroleukemia) with No.2 trisomy in Long-Evans rats. Activation of some oncogenes such as abl and Ha-ras has been reported to occur in relation to the secondary chromosomal translocations. In the present studies, a consistent type of mutation, A to T transversion in codon 61 of N-ras gene, was found in all of 6 cultured leukemia cell lines and 5 primary leukemias induced by DMBA. The N-ras mutation was also found in bone marrow cells of 2 out of 8 preleukemias. On the contrary, no mutation was observed in Ha- and Ki-ras genes in all leukemias and preleukemias. The consistent occurrence of above N-ras mutation in leukemias indicates that it plays an important role in DMBA-leukemogenesis.

Prognostic factors of patients with metastatic renal cell carcinoma with removed metastases: a multicenter study of 556 patients.

OBJECTIVE To investigate the prognosis and prognostic factors of patients with metastatic renal cell carcinoma who underwent metastasectomy. METHODS We sent questionnaires to Japanese hospitals. The questionnaires included data of patients with metastatic renal cell carcinoma who had their metastatic lesions removed between January 1988 and December 2009. We collected them and retrospectively analyzed these data and calculated the overall survival from the first metastasectomy until death or last follow-up. We also analyzed the relationship between survival and clinico-pathologic features and determined adverse prognostic factors. Furthermore, we identified a poor prognostic group by counting the number of prognostic factors. RESULTS A sample size of 556 patients from 48 institutions was studied. The median overall survival was 80 months. Four adverse prognostic factors were detected: incomplete resection by metastasectomy (hazard ratio [HR], 2.15), brain metastasis (HR, 3.73), >1.0 mg/dL C-reactive protein (HR, 2.45), and the highest histologic grade in Japanese classification (nuclei of tumor cells are larger than nuclei of normal tubular cells; HR, 1.88). The median overall survivals of patients with 3 or 4 prognostic factors, 2 factors, and 0 and 1 factors were 10 months, 42 months, and 105 months, respectively. CONCLUSION Four adverse prognostic factors for predicting the survival of patients with removed metastases were identified. Patients with 3 or 4 of these adverse prognostic factors had a worse prognosis.

Increased Akt and phosphorylated Akt expression are associated with malignant biological features of prostate cancer in Japanese men.

To investigate the relationship between the expression of Akt (a serine/threonine kinase that plays a central role in tumorigenesis), phosphorylated Akt (p‐Akt), prostate cancer tumour grade, androgen receptor (AR)‐staining score, and Ki67 labelling index (LI) in Japanese men.

Carcinosarcoma arising in mixed epithelial and stromal tumor of the kidney

Mixed epithelial and stromal tumor of the kidney (MESTK) is characterized macroscopically by a mixture of solid and cystic parts and microscopically by a mixture of an epithelial component resembling collecting ducts and showing müllerian differentiation in a stromal component (1–3). We here report the first case of carcinosarcoma suggesting malignant müllerian mixed tumor arising in MESTK. A 54-year-old woman presented with macroscopic hematuria. A renal tumor measuring 7.6 cm in maximum diameter was observed in the upper pole of the left kidney. No tumors were seen in the uterus or ovaries. Metastatic disease was ruled out. The patient died of systemic metastases 5 months after radical nephrectomy. Metastases were not histologically confirmed. Macroscopically, the tumor had a predominantly cystic appearance with solid areas; microscopically, it was composed of a mixture of epithelial and stromal components. The benignlooking epithelial cells resembled the collecting duct system, endometrial or tubal epithelium. Proliferation of the spindle cells resembled ovarian stroma or smooth muscle-like structures. The malignant neoplastic cells formed approximately 40% of the total neoplastic mass. The malignant epithelial cells showed the histologic features of adenocarcinoma with endometrioid features and pseudostratification of round to oval nuclei (Fig. 1A). Additionally, malignant stromal components resembling undifferentiated sarcoma, chondrosarcoma (Fig. 1B) or rhabdomyosarcoma (Fig. 1C) were detected. Immunohistochemically, the adenocarcinomatous and sarcomatous components were diffusely positive for CD10 (Fig. 1D). SYT-SSX fusion transcripts were not detected in the ma-