Hiroshi Miyamoto

Prof. Hiroshi Miyamoto

University of Rochester Medical Center
orcid

Research Focus & Metrics

Academic Career Length

35Years (1992-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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3 April 2007 in JNCI: Journal of the National Cancer Institute
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Journal Article
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Hiroshi MiyamotoHiroshi Miyamoto
Hiroshi Miyamoto
ZYZhiming Yang
Zhiming Yang
YCYei-Tsung Chen
Yei-Tsung Chen
HIHitoshi Ishiguro
Hitoshi Ishiguro
HUHiroji Uemura
Hiroji Uemura
CCChawnshang Chang
Chawnshang Chang
Males have a higher incidence of bladder cancer than females, but the reason remains unknown. Unlike prostate cancer, human bladder cancer is not generally considered to be dependent on hormone activity. We investigated the possible involvement of androgens and the androgen receptor (AR) in bladder cancer. We used N -butyl- N -(4-hydroxybutyl)nitrosamine (BBN) to induce bladder cancer in wild-type male and female mice, with and without castration in males, and in AR knockout (ARKO) male and female mice, with and without dihydrotestosterone (DHT) supplementation in males. We also treated human bladder cancer cell lines, including TCC-SUP and UMUC3, and mouse xenograft models established from these same lines with androgen deprivation therapy (antiandrogen treatment or castration), AR–small-interfering RNA (AR-siRNA), or the anti-AR molecule ASC-J9, which causes selective degradation of the AR. More than 92% of wild-type male and 42% of wild-type female mice treated with BBN eventually developed bladder cancer, whereas none of the male or female ARKO mice did. Treatment with BBN induced bladder cancer in 25% of ARKO mice supplemented with DHT and in 50% of castrated wild-type male mice. Androgen deprivation of AR-positive human bladder cancer cells by androgen depletion in vitro or castration in mice and/or by treatment with the antiandrogen flutamide in vitro or in vivo, as well as AR knockdown by AR-siRNA or by ASC-J9, suppressed cell proliferation in vitro and xenograft tumor growth in vivo. Our findings implicate the involvement of both androgens and the AR in bladder cancer. Targeting AR and androgens may provide novel chemopreventive and therapeutic approaches for bladder cancer.

26 April 2004 in The Prostate
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Hiroshi MiyamotoHiroshi Miyamoto
Hiroshi Miyamoto
EMEdward M. Messing
Edward M. Messing
CCChawnshang Chang
Chawnshang Chang

26 June 2020 in Archives of Pathology & Laboratory Medicine
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Journal Article
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JEJonathan I. Epstein
Jonathan I. Epstein
MAMahul B. Amin
Mahul B. Amin
SFSamson W. Fine
Samson W. Fine
FAFerran Algaba
Ferran Algaba
MAManju Aron
Manju Aron
KTKiril Trpkov
Kiril Trpkov
Context.—: Controversies and uncertainty persist in prostate cancer grading. Objective.—: To update grading recommendations. Data Sources.—: Critical review of the literature along with pathology and clinician surveys. Conclusions.—: Percent Gleason pattern 4 (%GP4) is as follows: (1) report %GP4 in needle biopsy with Grade Groups (GrGp) 2 and 3, and in needle biopsy on other parts (jars) of lower grade in cases with at least 1 part showing Gleason score (GS) 4 + 4 = 8; and (2) report %GP4: less than 5% or less than 10% and 10% increments thereafter. Tertiary grade patterns are as follows: (1) replace “tertiary grade pattern” in radical prostatectomy (RP) with “minor tertiary pattern 5 (TP5),” and only use in RP with GrGp 2 or 3 with less than 5% Gleason pattern 5; and (2) minor TP5 is noted along with the GS, with the GrGp based on the GS. Global score and magnetic resonance imaging (MRI)-targeted biopsies are as follows: (1) when multiple undesignated cores are taken from a single MRI-targeted lesion, an overall grade for that lesion is given as if all the involved cores were one long core; and (2) if providing a global score, when different scores are found in the standard and the MRI-targeted biopsy, give a single global score (factoring both the systematic standard and the MRI-targeted positive cores). Grade Groups are as follows: (1) Grade Groups (GrGp) is the terminology adopted by major world organizations; and (2) retain GS 3 + 5 = 8 in GrGp 4. Cribriform carcinoma is as follows: (1) report the presence or absence of cribriform glands in biopsy and RP with Gleason pattern 4 carcinoma. Intraductal carcinoma (IDC-P) is as follows: (1) report IDC-P in biopsy and RP; (2) use criteria based on dense cribriform glands (>50% of the gland is composed of epithelium relative to luminal spaces) and/or solid nests and/or marked pleomorphism/necrosis; (3) it is not necessary to perform basal cell immunostains on biopsy and RP to identify IDC-P if the results would not change the overall (highest) GS/GrGp part per case; (4) do not include IDC-P in determining the final GS/GrGp on biopsy and/or RP; and (5) “atypical intraductal proliferation (AIP)” is preferred for an intraductal proliferation of prostatic secretory cells which shows a greater degree of architectural complexity and/or cytological atypia than typical high-grade prostatic intraepithelial neoplasia, yet falling short of the strict diagnostic threshold for IDC-P. Molecular testing is as follows: (1) Ki67 is not ready for routine clinical use; (2) additional studies of active surveillance cohorts are needed to establish the utility of PTEN in this setting; and (3) dedicated studies of RNA-based assays in active surveillance populations are needed to substantiate the utility of these expensive tests in this setting. Artificial intelligence and novel grading schema are as follows: (1) incorporating reactive stromal grade, percent GP4, minor tertiary GP5, and cribriform/intraductal carcinoma are not ready for adoption in current practice.

5 January 2012 in BJU International
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Hiroshi MiyamotoHiroshi Miyamoto
Hiroshi Miyamoto
JYJorge L. Yao
Jorge L. Yao
ACAlcides Chaux
Alcides Chaux
YZYichun Zheng
Yichun Zheng
IHIawen Hsu
Iawen Hsu
SYShuyuan Yeh
Shuyuan Yeh
What's known on the subject? and What does the study add? Steroid hormone receptor signals have been implicated in bladder tumourigenesis and tumour progression. The expression of androgen and/or oestrogen receptors has been assessed in bladder cancer, leading to conflicting data of expression levels and their relationship to histopathological characteristics of the tumours. We simultaneously analyze three receptors in non‐neoplastic bladder tissues as well as in primary and metastatic bladder tumour specimens. Our data demonstrate that the expression status correlates with tumour grades/stages and patients’ outcomes. OBJECTIVE: To assess the expression of the androgen receptor (AR) and oestrogen receptors (ERs) in bladder tumours because recent studies have shown conflicting results and the prognostic significance of their expression remains unclear. PATIENTS AND METHODS: We investigated the expression of AR, ERα and ERβ in 188 bladder tumour specimens, as well as matched 141 non‐neoplastic bladder and 14 lymph node metastasis tissues, by immunohistochemistry. We then evaluated the relationships between their expression and the clinicopathological features available for the present patient cohort. RESULTS: AR/ERα/ERβ was positive in 80%/50%/89% of benign urothelium, 50%/67%/41% of benign stroma, 42%/27%/49% of primary tumours and 71%/64%/71% of metastatic tumours. Significantly lower expression of AR/ERα was found in high‐grade tumours (36%/23%) and tumours invading muscularis propria (33%/19%) compared to low‐grade tumours (55%; P = 0.0232/38%; P = 0.0483) and tumours not invading muscularis propria (51%; P = 0.0181/35%; P = 0.0139), respectively. Significantly higher expression of ERβ was found in high‐grade tumours (58%) and tumours invading muscularis propria (67%) compared to low‐grade tumours (29%; P = 0.0002) and tumours not invading muscularis propria (34%; P < 0.0001), respectively. Kaplan–Meier and log‐rank tests further showed that positivity of ERβ (but not AR or ERα) was associated with the recurrence of low‐grade tumours ( P = 0.0072); the progression of low‐grade tumours ( P = 0.0005), high‐grade tumours not invading muscularis propria ( P = 0.0020) and tumours invading muscularis propria ( P = 0.0010); or disease‐specific mortality in patients with tumours invading muscularis propria ( P = 0.0073). CONCLUSIONS: Compared to benign bladders, a significant decrease in the expression of AR, ERα or ERβ in bladder cancer was seen. Loss of AR or ERα was strongly associated with higher grade/more invasive tumours, whereas ERβ expression was increased in high‐grade/invasive tumours and predicted a worse prognosis.

12 May 1998 in Proceedings of the National Academy of Sciences
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SYShuyuan Yeh
Shuyuan Yeh
Hiroshi MiyamotoHiroshi Miyamoto
Hiroshi Miyamoto
HSHiroki Shima
Hiroki Shima
CCChawnshang Chang
Chawnshang Chang
While all three coactivators ARA 70 , steroid receptor coactivator 1, and RAC3/ACTR can enhance androgen receptor (AR) transcriptional activity at 1 nM dihydrotestosterone, we here demonstrate that only ARA 70 can induce AR transcriptional activity >30-fold in the presence of 10 nM 17β-estradiol (E2), but not diethylstilbestrol. The significance of this newly described E2-induced AR transcriptional activity in DU145 human prostate cancer cells was further strengthened by finding patients with Reifenstein partial-androgen-insensitive syndrome that fail in the E2-AR-ARA 70 pathway. Together, our data suggest, for the first time, testosterone/dihydrotestosterone may not be the only ligands for the AR. E2 represents another important natural ligand for AR that may play an essential role for the AR function and the development of the male reproductive system.

23 June 1998 in Proceedings of the National Academy of Sciences
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Hiroshi MiyamotoHiroshi Miyamoto
Hiroshi Miyamoto
SYShuyuan Yeh
Shuyuan Yeh
GWGeorge Wilding
George Wilding
CCChawnshang Chang
Chawnshang Chang
Although hormone therapy with antiandrogens has been widely used for the treatment of prostate cancer, some antiandrogens may act as androgen receptor (AR) agonists that may result in antiandrogen withdrawal syndrome. The molecular mechanism of this agonist response, however, remains unclear. Using mammalian two-hybrid assay, we report that antiandrogens, hydroxyflutamide, bicalutamide (casodex), cyproterone acetate, and RU58841, and other compounds such as genistein and RU486, can promote the interaction between AR and its coactivator, ARA70, in a dose-dependent manner. The chloramphenicol acetyltransferase assay further demonstrates that these antiandrogens and related compounds significantly enhance the AR transcriptional activity by cotransfection of AR and ARA70 in a 1:3 ratio into human prostate cancer DU145 cells. Our results suggest that the agonist activity of antiandrogens might occur with the proper interaction of AR and ARA70 in DU145 cells. These findings may provide a good model to develop better antiandrogens without agonist activity.