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result(s) for
"Sakamoto, Hiromasa"
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Detection of von Hippel‐Lindau gene mutation in circulating cell‐free DNA for clear cell renal cell carcinoma
2021
The therapeutic landscape of metastatic clear cell renal cell carcinoma (ccRCC) has rapidly expanded, and there is an urgent need to develop noninvasive biomarkers that can select an optimal therapy or evaluate the response in real time. To evaluate the clinical utility of circulating tumor DNA (ctDNA) analysis in ccRCC, we established a highly sensitive assay to detect mutations in von Hippel‐Lindau gene (VHL) using a combination of digital PCR and multiplex PCR–based targeted sequencing. The unique assay could detect VHL mutations with a variant allele frequency (VAF) <1.0%. Further, we profiled the mutation status of VHL in 76 cell‐free DNA (cfDNA) and 50 tumor tissues from 56 patients with ccRCC using the assay. Thirteen VHL mutations were identified in cfDNA from 12 (21.4%) patients with a median VAF of 0.78% (range, 0.13%‐4.20%). Of the 28 patients with VHL mutations in matched tumor tissues, eight (28.6%) also had VHL mutation in cfDNA with a median VAF of 0.47% (range, 0.13%‐2.88%). In serial ctDNA analysis from one patient, we confirmed that the VAF of VHL mutation changed consistent with tumor size by radiographic imaging during systemic treatment. In conclusion, VHL mutation in cfDNA was detected only in a small number of patients even using the highly sensitive assay; nevertheless, we showed the potential of ctDNA analysis as a novel biomarker in ccRCC.
Somatic genome profiling of cell‐free DNA (cfDNA) and matched tumor tissues from patients with clear cell renal cell carcinoma focusing on VHL mutations was conducted. By combination of digital PCR and targeted sequencing, thirteen VHL mutations were identified in cfDNA from 12 (21.4%) patients with a median VAF of 0.78% (range, 0.13%‐4.20%). Of the 28 patients with VHL mutations in matched tumor tissues, eight (28.6%) also had VHL mutation in cfDNA with a median VAF of 0.47% (range, 0.13%‐2.88%).
Journal Article
Squamous cell and urothelial carcinomas in an ileal neobladder
2022
Introduction
In cases of ileal neobladder following radical cystectomy for the treatment of bladder cancer, tumor development in the isolated gut segment is extremely rare. Herein, we report a case of squamous cell and urothelial carcinomas in the ileal neobladder 23 years after radical cystectomy.
Case presentation
A 71‐year‐old man was referred to our hospital for further examination of a solitary tumor in an ileal neobladder. At the age of 48 years, he underwent radical cystectomy with ileal neobladder reconstruction. Transurethral resection of the bladder tumor was performed, and histopathological findings showed squamous cell carcinoma with high‐grade urothelial carcinoma.
Conclusion
To our knowledge, this is the first report of squamous cell and urothelial carcinomas in an ileal neobladder. While secondary tumor development in an ileal neobladder is rare, it is a cause for concern as a late postoperative adverse event. Therefore, long‐term follow‐ups are recommended.
Journal Article
Role of IL13RA2 in Sunitinib Resistance in Clear Cell Renal Cell Carcinoma
by
Tsuruyama, Tatsuaki
,
Sakamoto, Hiromasa
,
Utsunomiya, Noriaki
in
Analysis
,
Animals
,
Antineoplastic agents
2015
Vascular endothelial growth factor (VEGF) and mammalian target of rapamycin are well-known therapeutic targets for renal cell carcinoma (RCC). Sunitinib is an agent that targets VEGF receptors and is considered to be a standard treatment for metastatic or unresectable clear cell RCC (ccRCC). However, ccRCC eventually develops resistance to sunitinib in most cases, and the mechanisms underlying this resistance are not fully elucidated. In the present study, we established unique primary xenograft models, KURC1 (Kyoto University Renal Cancer 1) and KURC2, from freshly isolated ccRCC specimens. The KURC1 xenograft initially responded to sunitinib treatment, however finally acquired resistance. KURC2 retained sensitivity to sunitinib for over 6 months. Comparing gene expression profiles between the two xenograft models with different sensitivity to sunitinib, we identified interleukin 13 receptor alpha 2 (IL13RA2) as a candidate molecule associated with the acquired sunitinib-resistance in ccRCC. And patients with high IL13RA2 expression in immunohistochemistry in primary ccRCC tumor tends to have sunitinib-resistant metastatic site. Next, we showed that sunitinib-sensitive 786-O cells acquired resistance in vivo when IL13RA2 was overexpressed. Conversely, shRNA-mediated knockdown of IL13RA2 successfully overcame the sunitinib-resistance in Caki-1 cells. Histopathological analyses revealed that IL13RA2 repressed sunitinib-induced apoptosis without increasing tumor vasculature in vivo. To our knowledge, this is a novel mechanism of developing resistance to sunitinib in a certain population of ccRCC, and these results indicate that IL13RA2 could be one of potential target to overcome sunitinib resistance.
Journal Article
Spontaneous remission of rectal ulcer associated with SpaceOAR® hydrogel insertion in radiotherapy for prostate cancer
2020
Introduction
The SpaceOAR® hydrogel system separates the prostate and rectum to reduce rectal irradiation during prostate radiotherapy. However, it could induce rectal toxicity.
Case presentation
A 75‐year‐old man with localized prostate cancer underwent external beam radiotherapy with the use of SpaceOAR® System. However, postimplant magnetic resonance imaging showed hydrogel infiltration to the rectum. Three months after implantation, he complained of bowel symptoms, including bloody stool. Colonofiberscopy and computed tomography revealed a rectal ulcer associated with SpaceOAR® hydrogel insertion. He was treated with fasting, fluid replacement, and blood transfusion. One year after implantation, complete healing was confirmed during outpatient follow‐up.
Conclusion
To our knowledge, this is the first report of a rectal ulcer associated with SpaceOAR® hydrogel insertion assessed by magnetic resonance imaging beforehand. Postimplant magnetic resonance imaging evaluation might be a useful follow‐up tool in such cases.
Journal Article
An EP4 Antagonist ONO-AE3-208 Suppresses Cell Invasion, Migration, and Metastasis of Prostate Cancer
by
Zhang, Zhengyu
,
Xu, Song
,
Sakamoto, Hiromasa
in
Animals
,
Antineoplastic Agents - pharmacology
,
Antineoplastic Agents - therapeutic use
2014
EP4 is one of the prostaglandin E2 receptors, which is the most common prostanoid and is associated with inflammatory disease and cancer. We previously reported that over-expression of EP4 was one of the mechanisms responsible for progression to castration-resistant prostate cancer, and an EP4 antagonist ONO-AE3-208 in vivo suppressed the castration-resistant progression regulating the activation of androgen receptor. The aim of this study was to analyze the association of EP4 with prostate cancer metastasis and the efficacy of ONO-AE3-208 for suppressing the metastasis. The expression levels of EP4 mRNA were evaluated in prostate cancer cell lines, LNCaP, and PC3. EP4 over-expressing LNCaP was established, and their cell invasiveness was compared with the control LNCaP (LNCaP/mock). The in vitro cell proliferation, invasion, and migration of these cells were examined under different concentrations of ONO-AE3-208. An in vivo bone metastatic mouse model was constructed by inoculating luciferase expressing PC3 cells into left ventricle of nude mice. Their bone metastasis was observed by bioluminescent imaging with or without ONO-AE3-208 administration. The EP4 mRNA expression levels were higher in PC3 than in LNCaP, and EP4 over-expression of LNCaP cells enhanced their cell invasiveness. The in vitro cell invasion and migration were suppressed by ONO-AE3-208 in a dose-dependent manner without affecting cell proliferation. The in vivo bone metastasis of PC3 was also suppressed by ONO-AE3-208 treatment. EP4 expression levels were correlated with prostate cancer cell invasiveness and EP4 specific antagonist ONO-AE3-208 suppressed cell invasion, migration, and bone metastasis, indicating that it is a potential novel therapeutic modality for the treatment of metastatic prostate cancer.
Journal Article
Amino‐terminal enhancer of split gene AES encodes a tumor and metastasis suppressor of prostate cancer
2017
A major cause of cancer death is its metastasis to the vital organs. Few effective therapies are available for metastatic castration‐resistant prostate cancer (PCa), and progressive metastatic lesions such as lymph nodes and bones cause mortality. We recently identified AES as a metastasis suppressor for colon cancer. Here, we have studied the roles of AES in PCa progression. We analyzed the relationship between AES expression and PCa stages of progression by immunohistochemistry of human needle biopsy samples. We then performed overexpression and knockdown of AES in human PCa cell lines LNCaP, DU145 and PC3, and determined the effects on proliferation, invasion and metastasis in culture and in a xenograft model. We also compared the PCa phenotypes of Aes/Pten compound knockout mice with those of Pten simple knockout mice. Expression levels of AES were inversely correlated with clinical stages of human PCa. Exogenous expression of AES suppressed the growth of LNCaP cells, whereas the AES knockdown promoted it. We also found that AES suppressed transcriptional activities of androgen receptor and Notch signaling. Notably, AES overexpression in AR‐defective DU145 and PC3 cells reduced invasion and metastasis to lymph nodes and bones without affecting proliferation in culture. Consistently, prostate epithelium‐specific inactivation of Aes in Ptenflox/flox mice increased expression of Snail and MMP9, and accelerated growth, invasion and lymph node metastasis of the mouse prostate tumor. These results suggest that AES plays an important role in controlling tumor growth and metastasis of PCa by regulating both AR and Notch signaling pathways.
Aes suppresses metastatic spread of human prostate cancer cell grafts to the bone in mice. In vivo bioluminescence images of mice injected with luciferase‐expressing PC3 cels into the left cardiac ventricle.
Journal Article
Improvement of prognosis in patients with metastatic renal cell carcinoma and Memorial Sloan-Kettering Cancer Center intermediate risk features by modern strategy including molecular-targeted therapy in clinical practice
2014
Objectives
To identify the patient subgroups benefitting the most from the modern strategy including molecular-targeted therapy among patients with metastatic renal cell carcinoma (mRCC) in clinical practice.
Methods
Retrospective analysis of 144 patients with mRCC diagnosed between 1992 and 2011 at Kyoto University Hospital was conducted. Multivariate analysis using the Cox proportional hazards model was conducted to identify prognostic factors associated with overall survival (OS). Subgroup analysis was conducted to identify patients who benefitted the most from molecular-targeted therapy.
Results
Independent factors associated with worse OS are: tumors of histological type other than clear-cell, decreased hemoglobin (Hb), elevated lactate dehydrogenase (LDH), elevated C-reactive protein (CRP), and metastases at ≥ 3 sites. Median OS of patients treated with molecular-targeted therapy alone or with prior immunotherapy and those treated with immunotherapy alone was 57, 45 and 28 months, respectively. Molecular-targeted therapy had more effect on OS than immunotherapy alone among female patients, patients with Memorial Sloan-Kettering Cancer Center (MSKCC) intermediate risk features, and patients with metastatic progression less than 1 year after initial diagnosis of RCC, compared with their counterparts.
Conclusions
The modern strategy including molecular-targeted therapy may improve OS in patients with mRCC and MSKCC intermediate risk features in clinical practice, relative to those with other risk features. However, the prognosis for patients with tumors of histological type other than clear-cell, decreased Hb, elevated LDH, elevated CRP, or metastases at ≥ 3 sites remains poor even in the modern molecular-targeted era. Novel treatment strategies are necessary to improve prognosis in these patients.
Journal Article
A family case with germline TSC1 and mtDNA mutations developing bilateral eosinophilic chromophobe renal cell carcinomas without other typical phenotype of tuberous sclerosis
by
Sakamoto, Hiromasa
,
Utsunomiya, Noriaki
,
Takeda, Masashi
in
Adult
,
Cancer
,
Carcinoma, Renal Cell - genetics
2018
AimWe examined the genetic alterations in a mother and son with multiple eosinophilic chromophobe renal cell carcinomas (chRCCs) showing no other features.MethodsGermline DNA and bilateral renal cell carcinoma DNA were genetically analysed by whole-exome sequencing. Candidate gene alterations in the first patient’s germline were investigated in her child’s germline and the chRCCs.ResultsWe detected several germline gene alterations in the mother. Among the identified alterations, TSC1 and mitochondrial DNA mutations were also confirmed in her son. Regarding somatic alterations in bilateral chRCCs, no common candidate gene alteration was found.ConclusionTo the best of our knowledge, this is the first report of whole-exome sequencing revealing bilateral eosinophilic chRCCs associated with tuberous sclerosis complex in a family case without classical phenotype. These results suggest that germline TSC1 and mitochondrial DNA gene mutations may be involved in the development of chRCCs in some cases.
Journal Article
CCL2 as a potential therapeutic target for clear cell renal cell carcinoma
by
Tsuruyama, Tatsuaki
,
Sakamoto, Hiromasa
,
Utsunomiya, Noriaki
in
Adult
,
Aged
,
Aged, 80 and over
2016
We previously reported that the pVHL‐atypical PKC‐JunB pathway contributed to promotion of cell invasiveness and angiogenesis in clear cell renal cell carcinoma (ccRCC), and we detected chemokine (C‐C motif) ligand‐2 (CCL2) as one of downstream effectors of JunB. CCL2 plays a critical role in tumorigenesis in other types of cancer, but its role in ccRCC remains unclear. In this study, we investigated the roles and therapeutic potential of CCL2 in ccRCC. Immunohistochemical analysis of CCL2 expression for ccRCC specimens showed that upregulation of CCL2 expression correlated with clinical stage, overall survival, and macrophage infiltration. For functional analysis of CCL2 in ccRCC cells, we generated subclones of WT8 cells that overexpressed CCL2 and subclones 786‐O cells in which CCL2 expression was knocked down. Although CCL2 expression did not affect cell proliferation in vitro, CCL2 overexpression enhanced and CCL2 knockdown suppressed tumor growth, angiogenesis, and macrophage infiltration in vivo. We then depleted macrophages from tumor xenografts by administration of clodronate liposomes to confirm the role of macrophages in ccRCC. Depletion of macrophages suppressed tumor growth and angiogenesis. To examine the effect of inhibiting CCL2 activity in ccRCC, we administered CCL2 neutralizing antibody to primary RCC xenografts established from patient surgical specimens. Inhibition of CCL2 activity resulted in significant suppression of tumor growth, angiogenesis, and macrophage infiltration. These results suggest that CCL2 is involved in angiogenesis and macrophage infiltration in ccRCC, and that CCL2 could be a potential therapeutic target for ccRCC.
Antiangiogenic‐targeted therapies are used for treatment of advanced renal cell carcinoma. Our clinical data, corroborated by xenograft models, suggest that CCL2 is involved in tumor progression and may serve as novel therapeutic target for clear cell renal cell carcinoma.
Journal Article