Takayuki Sugiyama

Evaluation of S100A10, annexin II and B‐FABP expression as markers for renal cell carcinoma

This study aimed to analyze expression of S100A10, annexin II and B‐FABP genes in renal cell carcinoma (RCC) and their potential value as tumor markers. Furthermore, any correlation between the gene expression and prognostic indicators of RCC was analyzed. Expression of each gene was estimated by RT‐PCR in the non‐neoplastic (normal) and tumorous parts of resected kidney samples. Also, each antigen was immunostained in RCC and normal kidney tissues. Expression of the S100A10 gene averaged 2.5‐fold higher in the tumor than that in the normal tissues (n = 47), after standardization against that of β‐actin. However, expression of annexin II, a natural ligand of S100A10, was only 1.64‐fold higher. In the tissue sections of RCC, S100A10 and annexin II were immunostained in membranes. In the normal renal epithelia, however, both antigens were stained in the Bowmans capsule and the tubules from Henles loop through the collecting duct system, but not in the proximal tubules, from where most RCC are derived. In contrast, expression of the B‐FABP gene was 20‐fold higher in the tumor. No B‐FABP was immunohistochemically detected in normal kidney sections, but it was stained in the cytoplasm of RCC tissue sections. S100A10 and B‐FABP genes were overexpressed regardless of nuclear grade and stage of RCC. Immunopositivity in RCC tissues (n = 13) was 100% for S100A10 and annexin II, and 70% for B‐FABP; however, no clear relationship was observed in either antigen with nuclear grade and stage. It was found that all three performed well as RCC markers. B‐FABP was most specific to RCC, as it was expressed little in normal kidney tissues. (Cancer Sci 2007; 98: 77–82)

Analysis of the regulation of fatty acid binding protein 7 expression in human renal carcinoma cell lines

BackgroundImproving the treatment of renal cell carcinoma (RCC) will depend on the development of better biomarkers for predicting disease progression and aiding the design of appropriate therapies. One such marker may be fatty acid binding protein 7 (FABP7), also known as B-FABP and BLBP, which is expressed normally in radial glial cells of the developing central nervous system and cells of the mammary gland. Melanomas, glioblastomas, and several types of carcinomas, including RCC, overexpress FABP7. The abundant expression of FABP7 in primary RCCs compared to certain RCC-derived cell lines may allow the definition of the molecular components of FABP7s regulatory system.ResultsWe determined FABP7 mRNA levels in six RCC cell lines. Two were highly expressed, whereas the other and the embryonic kidney cell line (HEK293) were weakly expressed FABP7 transcripts. Western blot analysis of the cell lines detected strong FABP7 expression only in one RCC cell line. Promoter activity in the RCC cell lines was 3- to 21-fold higher than that of HEK293. Deletion analysis demonstrated that three FABP7 promoter regions contributed to upregulated expression in RCC cell lines, but not in the HEK293 cell. Competition analysis of gel shifts indicated that OCT1, OCT6, and nuclear factor I (NFI) bound to the FABP7 promoter region. Supershift experiments indicated that BRN2 (POU3F2) and NFI bound to the FABP7 promoter region as well. There was an inverse correlation between FABP7 promoter activity and BRN2 mRNA expression. The FABP7-positive cell lines NFI-DNA complex migrated faster than in other cell lines. Levels of NFIA mRNA were higher in the HEK293 cell line than in any of the six RCC cell lines. In contrast, NFIC mRNA expression was lower in the HEK293 cell line than in the six RCC cell lines.ConclusionsThree putative FABP7 promoter regions drive reporter gene expression in RCC cell lines, but not in the HEK293 cell line. BRN2 and NFI may be key factors regulating the expression of FABP7 in certain RCC-derived cell lines.

Comparative Assessment of Efficacies Between 2 Alternative Therapeutic Sequences With Novel Androgen Receptor-Axis-Targeted Agents in Patients With Chemotherapy-Naïve Metastatic Castration-Resistant Prostate Cancer

Background The objective of this study was to compare the efficacies of sequential therapies with novel androgen receptor‐axis‐targeted (ARAT) agents in patients with docetaxel‐naïve metastatic castration‐resistant prostate cancer (mCRPC). Patients and Methods This study included 108 consecutive patients with mCRPC who sequentially received abiraterone acetate (AA) and enzalutamide (Enz), in either order, without prior treatment with docetaxel. The combined prostate‐specific antigen (PSA) progression‐free survival (PFS) was defined as the sum of PFS1 and PFS2, representing PSA PFSs on the first and second ARAT agents, respectively. Results Of these patients, 49 and 59 received ARAT therapy with the AA‐to‐Enz sequence (AA‐to‐Enz group) and with the reverse sequence (Enz‐to‐AA group), respectively. No significant differences in the baseline characteristics were noted between the 2 groups. In the overall patient population, the PSA response rate to the second‐line ARAT agent (21.3%) was significantly lower than that of the first‐line ARAT agent (58.3%). The combined PSA PFS in the AA‐to‐Enz group (median, 18.4 months) was significantly superior to that of the Enz‐to‐AA group (median, 12.8 months). Furthermore, multivariate analysis identified the treatment sequence (ie, AA‐to‐Enz vs. Enz‐to‐AA group) in addition to performance status as an independent predictor of combined PSA PFS in these patients. However, there was no significant difference in overall survival (OS) between the 2 groups. Conclusions Although cross‐resistance between ARAT agents is a common phenomenon in docetaxel‐naïve patients with mCRPC, different efficacies were observed favoring the AA‐to‐Enz rather than Enz‐to‐AA sequence in this series with respect to combined PSA PFS but not OS. Micro‐Abstract The investigation of the efficacy of sequential therapies with novel androgen receptor‐axis‐targeted (ARAT) agents for docetaxel‐naïve patients with metastatic castration‐resistant prostate cancer revealed the superiority of the abiraterone‐to‐enzalutamide sequence over the reverse sequence regarding combined prostate‐specific antigen progression‐free survival, but not overall survival. Therefore, despite the occurrence of cross‐resistance with either sequence, ARAT therapy with the abiraterone‐to‐enzalutamide sequence might be preferable.

Reduced expression of the DNA glycosylase gene MUTYH is associated with an increased number of somatic mutations via a reduction in the DNA repair capacity in prostate adenocarcinoma

8‐Hydroxyguanine (8OHG), a major oxidative DNA lesion, is known to accumulate in prostate cancer; however, the status of one of its repair enzymes, MUTYH, in prostate cancer remains to be elucidated. In this study, we showed that the expression levels of MUTYH mRNA and protein were significantly lower in prostate cancer than in non‐cancerous prostatic tissue by examining two independent, publicly available databases and by performing an immunohistochemical analysis of prostate cancer specimens obtained at our hospital, respectively. About two‐thirds of the prostate cancers exhibited a reduced MUTYH expression. When the effect of reduced MUTYH expression in prostate adenocarcinoma on the somatic mutation load was examined using data from the Cancer Genome Atlas (TCGA) database, the numbers of total somatic mutations and somatic G:C to T:A mutations were significantly higher in the reduced MUTYH expression group than in the other group (P < 0.0001 and P = 0.0013, respectively). To determine the reason why reduced MUTYH expression leads to somatic mutation loads in prostate adenocarcinoma, we compared the DNA repair capacities between PC‐3 prostatic cell line derived clones with different MUTYH expression levels. Both the capacities to cleave DNA containing adenine:8OHG mispairs and to suppress mutations caused by 8OHG were significantly lower in prostatic cell lines with lower MUTYH expression than in prostatic cell lines with higher MUTYH expression. These results suggested that reduced MUTYH expression is associated with somatic mutation loads via a reduction in DNA repair capacity in prostate adenocarcinoma.

Genetic Polymorphisms of CYP2A6 in a Case-Control Study on Bladder Cancer in Japanese Smokers

Several of the procarcinogens inhaled in tobacco smoke, the primary risk factor for bladder cancer, are activated by CYP2A6. The association between the whole-gene deletion of CYP2A6 (CYP2A6*4) and a reduced risk of bladder cancer was suggested in Chinese Han smokers. However, there is no evidence for association between the risk of bladder cancer and CYP2A6 genotypes in the Japanese population. Using genomic DNA from smokers of the Japanese population (163 bladder cancer patients and 116 controls), we conducted a case-control study to assess the association between CYP2A6 polymorphisms and the risk of bladder cancer. Determination of CYP2A6 genotypes was carried out by amplifying each exon of CYP2A6 using polymerase chain reaction (PCR) and Sanger sequencing. The CYP2A6*4 allele was identified by an allele-specific PCR assay. Bladder cancer risk was evaluated using the activity score (AS) system based on CYP2A6 genotypes. The odds ratios (95% confidence interval) for the AS 0, AS 0.5, AS 1.0, and AS 1.5 groups were 0.46 (0.12-1.83), 0.43 (0.15-1.25), 0.86 (0.40-1.86), and 1.36 (0.60-3.06), respectively. In conclusion, although decreased CYP2A6 AS tended to reduce the risk of bladder cancer in Japanese smokers, no significant association was recognized in this population. However, given the relatively small size of the sample, further study is required to conclude the lack of a statistically significant association between CYP2A6 genotypes and the risk of bladder cancer.

Impact of gender in renal cell carcinoma: the relationship of FABP7 and BRN2 expression with overall survival

Objective To investigate the relationship between gender differences in fatty acid-binding protein7 (FABP7) and BRN2 (POU class 3 homeobox 2) expression in renal cell carcinoma (RCC) and the prognosis of patients with RCC. Materials and Methods immunohistochemical (IHC) staining as well as reverse transcription-polymerase chain reaction (RT-PCR) was performed in renal tissues from 103 patients (83 men, mean age = 63.6 years old; 20 women, mean age = 63.1 years old) underwent radical nephrectomy from January 1, 2001 through December 31, 2010. The probability of overall patient survival was estimated using the Kaplan–Meier method. Results FABP7 mRNA expression was more frequent in men (P = 0.07) while BRN2 protein expression was significantly more frequent in women (P = 0.029). In particular, FABP7 was expressed in 100% of G1 renal cell carcinoma both in mRNA and protein levels. In women, FABP7 (–) and BRN2 (+) groups had a worse prognosis both in mRNA level (P = 0.038) and protein level (P = 0.058). BRN2 was expressed 100% of papillary RCC both in mRNA and protein levels. Conclusions Our results demonstrated that gender was a key factor in FABP7 and BRN2 expression in RCC, and the combination with FABP7 and BRN2 stratified by gender could be a new potential prognostic factor in patients with RCC.

Efficacy of Adjuvant Interferon-alpha Therapy Following Curative Resection in Renal Cell Carcinoma: Before the Molecular Targeting Therapy Era

OBJECTIVE Although present treatment programs for renal cell carcinoma (RCC) typically involve molecular-targeting drugs, interferon-alpha (IFN-alpha) remains an important therapeutic drug for this cancer. METHODS We evaluated the effect of adjuvant therapy in 508 patients with RCC following curative surgery. Patients were classified into one of the two categories based on the duration and the total dose of IFN-alpha treatment. RESULTS Median follow-up time was 65.5 months. Overall survival rates at 5, 10, 15 and 20 years were 88.8%, 80.5%, 69.6% and 54.1%, respectively. Cause-specific survival rates at 5, 10, 15 and 20 years were 95.0%, 89.1%, 83.0% and 83.0%, respectively. Coxs proportional hazard model revealed that C-reactive protein, T classification, histological grade and age were significantly independent factors indicative of a poor prognosis. Our examination of the 253 patients diagnosed as pT1-2N0M0 who underwent adjuvant IFN-alpha therapy following surgery found that the therapy was not significantly associated with either cause-specific or disease-free survival. With regard to effects of duration of therapy and total dose of IFN-alpha, patients with a total IFN-alpha exposure of > or = 180 x 10(6) international units (IU) had a better prognosis than those exposed to <180 x 10(6) IU. CONCLUSIONS Adjuvant therapy using large doses of IFN-alpha may improve the prognosis of patients with RCC following curative resection, and the new possibility of IFN-alpha therapy merits further investigation.

Axitinib Controlled Metastatic Renal Cell Carcinoma for 5 Years

We present two patients with a long-term response to axitinib for cytokine-refractory metastatic renal cell carcinoma. One patient has had a continuing partial response for 58 months with cytokine-intolerant metastatic renal cell carcinoma and the other patient has had continuing stable disease accompanied by a mixed response for 57 months with cytokine-refractory and intolerant metastatic renal cell carcinoma. The condition of hypertension as an adverse event markedly depended on whether or not axitinib was administered. The patients responded to axitinib with an elevation of diastolic blood pressure to 90 mmHg or higher until 2 weeks after starting axitinib. To get a long-term response to axitinib, it may be important to control well the balance between treatment effect and adverse events while using drug withdrawal.

Comparison of Alternative Androgen Receptor-axis-targeted Agent (ARATA) and Docetaxel as Second-line Therapy for Patients With Metastatic Castration-resistant Prostate Cancer With Progression After Initial ARATA in Real-world Clinical Practice in Japan

&NA; The present study included 222 patients with metastatic castration‐resistant prostate cancer. Of the 222 patients, 108 and 114 received an alternative androgen receptor‐axis‐targeted agent (ARATA) or docetaxel, respectively, after the failure of initial ARATA. We found that the oncologic outcomes, including the response rate, progression‐free survival, and overall survival, were significantly superior in the 114 patients receiving docetaxel compared with those of the 108 patients receiving ARATA. Background: The objective of the present study was to assess the oncologic outcomes of patients receiving second‐line therapy against metastatic castration‐resistant prostate cancer (mCRPC). Patients and Methods: The present study included 222 consecutive mCRPC patients with progression during initial androgen receptor‐axis‐targeted agent (ARATA) therapy with either abiraterone acetate (AA) or enzalutamide (Enz). Of these 222 patients, 108 subsequently received an alternative ARATA (AA‐to‐Enz, n = 49; Enz‐to‐AA, n = 59) and 114 received docetaxel (DTX; AA‐to‐DTX, n = 54; Enz‐to‐DTX, n = 60). Results: The prostate‐specific antigen (PSA) level in the 114 patients receiving DTX was significantly greater than that in the 108 patients receiving ARATA. However, no significant differences were found in the remaining parameters between the 2 groups. The PSA response rate, PSA progression‐free survival (PFS), and overall survival (OS) during second‐line therapy in the DTX group (n = 114) were significantly superior to those for the ARATA group (n = 108; PSA response rate, 42.1% vs. 21.3%; median PSA PFS, 7.2 vs. 4.2 months; median OS, 17.5 vs. 14.5 months). Similar trends were confirmed by comparing these outcomes among 4 therapy groups, with significant differences (PSA response rate, Enz‐to‐AA vs. AA‐to‐DTX and Enz‐to‐AA vs. Enz‐to‐DTX; PSA PFS, AA‐to‐Enz vs. Enz‐to‐AA, AA‐to‐Enz vs. AA‐to‐DTX, Enz‐to‐AA vs. AA‐to‐DTX, and Enz‐to‐AA vs. Enz‐to‐DTX; and OS, Enz‐to‐AA vs. AA‐to‐DTX and Enz‐to‐AA vs. Enz‐to‐DTX). Furthermore, the introduction of DTX was independently associated with improved PSA PFS, but not OS, on multivariate analysis. Conclusion: Favorable oncologic outcomes can be expected with DTX treatment, rather than with alternative ARATA, for mCRPC patients after failure of an initial ARATA.

Impact of Thymidine Phosphorylase-Expressing Macrophages for Surgical Margin in Partial Nephrectomy

Objectives: We investigated the relationship between the surgical margin in partial nephrectomy (PN) and thymidine phosphorylase (TP)-expressing macrophages in peritumoral tissue of renal cell carcinoma (RCC). Methods: In 46 patients who underwent radical nephrectomy, we measured TP protein levels in tumor tissue, peritumoral tissue and normal tissue, and conducted immunohistochemical staining for TP and macrophages. In addition, we prospectively conducted PN with a 5-mm margin in 11 patients with pT1a RCC. Results: The TP protein level and TP-positive macrophages were correlated with T classification, histological grade, mode of infiltration and venous invasion. However, for pT1 RCC, TP-positive macrophages in pT1a were significantly lower than in pT1b (p = 0.0140), while there was no significant difference in TP protein levels between pT1a and pT1b. No surgical margin was positive in 11 patients who underwent PN with a 5-mm margin, and no patient had local recurrence or distant metastasis during follow-up. Conclusions: The TP protein level and TP-positive macrophages in the peritumor area are thought to be associated with tumor progression in RCC, while a similar relationship was not found in pT1a RCC. These data suggest that a 5-mm margin might be safe to reduce the risk of local recurrence when PN is performed for treatment of solitary pT1a RCC.