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Dive into the research topics where Takehiro Sejima is active.

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Featured researches published by Takehiro Sejima.


European Urology | 1999

Expression of bcl-2, p53 oncoprotein, and proliferating cell nuclear antigen in renal cell carcinoma.

Takehiro Sejima; Ikuo Miyagawa

Objectives: This study was designed to examine the immunohistochemical expression of bcl-2, p53, and proliferating cell nuclear antigen (PCNA) and the relation of this expression to clinicopathological characteristics and prognosis in renal cell carcinoma (RCC). Methods: The expression of bcl-2, p53 protein, and PCNA was studied by immunohistochemical methods in paraffin-embedded nephrectomy specimens from 53 patients whose clinicopathological data had already become clear. Results: The expression of the bcl-2 protein was recognized in 34 cases (64%); the expression of the p53 protein, however, was seen in only 1 case. Bcl-2 positivity was not associated with any pathological parameters or prognosis. If the percentage of PCNA-positive cancer cells as compared to the total amount of cancer cells was defined as a labeling index (LI), a high PCNA LI number correlated significantly with a high T category, high grade, venous invasion, and shortened survival. Among the conventional pathological parameters, the T category, nuclear grade, and venous invasion had the most significant effect on prognosis. A multivariate analysis in the parameters of PCNA, T category, nuclear grade, and venous invasion demonstrated that only nuclear grade had a significant effect on prognosis. Conclusions: The inhibitory effect of the bcl-2 gene on apoptosis related to tumor development is not clear, and the expression of the p53 protein is uncommon in RCC. PCNA seems to be a good objective and quantitative marker of the biological malignant potential in RCC, although the assessment of malignant potential in combination with conventional pathological parameters is indispensable.


International Journal of Oncology | 2014

Serum miR-210 as a potential biomarker of early clear cell renal cell carcinoma.

Hideto Iwamoto; Yusuke Kanda; Takehiro Sejima; Mitsuhiko Osaki; Futoshi Okada; Atsushi Takenaka

Early detection and treatment are critical in the management of renal cell carcinoma (RCC). However, there is no standard serum biomarker to facilitate early diagnosis or prognostic stratification in patients with RCC. Recent reports suggest that circulating microRNAs (miRNAs) have great potential as biomarkers for diagnosis and prognosis in patients with several types of cancers. Further, many studies using miRNA microarray analysis demonstrated that miR-210 expression in clear cell carcinoma (CCC), which is the largest subtype of RCC, was significantly upregulated in tumor tissue. Therefore, we investigated whether serum miR-210 could be a useful biomarker for the diagnosis and progression of CCC. This study included 34 CCC patients and 23 healthy controls (HC). First, we analyzed tissue miR-210 levels in tumor tissues and matched normal tissues from the 34 CCC patients. Second, we investigated the serum miR-210 levels in the 34 CCC patients and the 23 HC patients. Real-time polymerase chain reaction (PCR) was used to measure miRNA levels. Moreover, we examined the correlation between serum miR-210 levels and the clinicopathological parameters. Among patients with CCC, expression of miR-210 was higher in tumor tissues compared to normal tissues (P<0.001). Serum miR-210 levels were higher in CCC patients compared to HCs (P=0.001). Receiver operating characteristic (ROC) curve analysis showed an area under the ROC curve (AUC) of 0.77 (95% confidence interval, 0.65-0.89) and a sensitivity and specificity of 65 and 83%, respectively. In addition, there was no significant association between serum miR-210 levels and age, sex, tumor size or existence of metastasis at diagnosis among the 34 CCC patients. In conclusion, serum miR-210 upregulation may occur in the early stage of CCC and serum miR-210 can be a useful biomarker for early CCC in humans.


Scientific Reports | 2015

Prostatic ischemia induces ventral prostatic hyperplasia in the SHR; possible mechanism of development of BPH

Motoaki Saito; Panagiota Tsounapi; Ryo Oikawa; Shogo Shimizu; Masashi Honda; Takehiro Sejima; Yukako Kinoshita; Shuhei Tomita

In the light of increasing evidence that benign prostatic hyperplasia is associated with cardiovascular disease, we have investigated the relationship between prostatic blood flow and prostatic hyperplasia in the spontaneously-hypertensive-rat (SHR). Twelve-week-old male SHRs were treated with nicorandil for six weeks. Wistar-Kyoto rats were used as controls. Six weeks after nicorandil treatment, blood pressure and the prostatic blood flow were estimated, and tissue levels of malondialdehyde, HIF-1α, TGF-β1, bFGF, dihydrotestosterone, and α-SMA were measured. SHRs showed significant increases in blood pressure, tissue levels of malondialdehyde, HIF-1α, TGF-β1, bFGF, α-SMA and a significant decrease in the prostatic blood flow. Although treatment with nicorandil failed to alter the blood-pressure and α-SMA, it significantly ameliorated the increased levels of malondialdehyde, HIF-1α, TGF-β1, and bFGF. There were no significant differences in tissue levels of dihydrotestosterone among any groups. These data indicate that development of prostatic hyperplasia may be associated with prostatic hypoxia, which nicorandil prevents via its effect to increase the blood flow.


Urologic Oncology-seminars and Original Investigations | 2013

The significant immunological characteristics of peripheral blood neutrophil-to-lymphocyte ratio and Fas ligand expression incidence in nephrectomized tumor in late recurrence from renal cell carcinoma

Takehiro Sejima; Hideto Iwamoto; Shuichi Morizane; Nobuyuki Hinata; Akihisa Yao; Tadahiro Isoyama; Motoaki Saito; Atsushi Takenaka

OBJECTIVE In order to characterize the significance of immune system function in patients with advanced renal cell carcinoma (RCC), we investigated the interactive relationships among the following parameters: metastatic characteristics, expression of Fas ligand (FasL) in nephrectomized specimens, immunological parameters, and patients prognosis. MATERIALS AND METHODS Thirty-five patients with advanced RCC were stratified into 3 groups according to the characteristics of metastasis timing, at first presentation (mFP), within 5 years of nephrectomy (early-recurrence), after 5 years (late-recurrence). Immunological parameters [hemoglobin, lymphocyte count, neutrophil/lymphocyte ratio (NLR), serum albumin, Eastern Cooperative Oncology Group (ECOG) performance status (PS), and Charlson Comorbidity Index], FasL expression in RCC, and patient prognosis from occurrence of metastasis were compared among the groups. Thirty-five patients were also stratified into 2 groups according to FasL positivity and individual parameters. Patients prognosis and the remaining immunological parameters were compared between groups. RESULTS The NLRs of the late-recurrence group were significantly lower than those of the mFP (P = 0.0004) and early-recurrence (P = 0.013) groups. The FasL mRNA positivity of the late-recurrence group was significantly lower than those of the mFP (P = 0.001) and early-recurrence (P = 0.0277) groups. The prognosis of the late-recurrence group was significantly better than that of the early-recurrence group (P = 0.0255). NLRs were significantly lower in the FasL-negative group than in the -positive group (P = 0.0182). The cause-specific survival rates of the ECOG PS 0 group were significantly higher than that of the ECOG PS > 0 group (P < 0.0001). CONCLUSIONS Our results suggest the associations of the prognosis in advanced RCC with peripheral blood NLR and FasL expression in nephrectomized tumor. The characteristics of lower values of NLR and FasL expression positivity in late-recurrence compared with other metastatic timings suggest strong host immune activity, and may imply relatively long survival. On the other hand, elucidation of the patients general condition obtained not only by chemical data but also by ECOG PS is crucial in the management of patients with advanced RCC.


International Journal of Urology | 2014

Prognostic impact of preoperative hematological disorders and a risk stratification model in bladder cancer patients treated with radical cystectomy.

Takehiro Sejima; Shuichi Morizane; Akihisa Yao; Tadahiro Isoyama; Motoaki Saito; Takashi Amisaki; Tsutomu Koumi; Atsushi Takenaka

The present study investigated prognostic indicators, including clinicopathological and preoperative hematological factors, and developed a prognostic factor‐based risk stratification model in bladder cancer patients treated with radical cystectomy.


Pharmacological Research | 2012

Hydroxyfasudil ameliorates penile dysfunction in the male spontaneously hypertensive rat

Motoaki Saito; Fumiya Ohmasa; Fotios Dimitriadis; Panagiota Tsounapi; Takehiro Sejima; Shogo Shimizu; Yukako Kinoshita; Keisuke Satoh

Hypertension represents a major risk factor for erectile dysfunction. Although the etiology of hypertension-induced erectile dysfunction is multifactorial and still unknown, Rho-Rho kinase pathway is one of the key factors. To investigate whether administration of hydroxyfasudil, a Rho kinase inhibitor could prevent dysfunction of NO-induced relaxation in corpus cavernosum smooth muscle in the SHR (spontaneously hypertensive rat), twelve-week-old male SHRs were treated with hydroxyfasudil (3 or 10 mg/kg, i.p.) once a day for 6 weeks. Wistar rats and SHRs treatment with vehicle were used as age-matched controls. Penile cGMP concentrations and Rho kinase activities were determined, and penile function was estimated by organ bath studies with norepinephrine-induced contractions and acetylcholine-induced relaxations. The participation mRNA levels of eNOS and participation protein levels of eNOS and phosphorylated eNOS were investigated by quantitative real-time PCR methods and immunoblot analysis, respectively. The SHR showed significantly decreased cGMP concentrations, increased Rho kinase activities, norepinephrine-induced hyper-contractions, and acetylcholine-induced hypo-relaxations in the penile tissue. Treatment with hydroxyfasudil significantly improved the decreased penile cGMP concentrations, the increased Rho kinase activities, the increased norepinephrine-induced contractions, and the decreased acetylcholine-induced relaxation in a dose-dependent manner. Although there were no significant differences in expression protein levels of eNOS among any of the groups, down-regulation of eNOS mRNAs as well as phosphorylated eNOS were significantly ameliorated after treatment with hydroxyfasudil. Our data suggest that hydroxyfasudil ameliorates hypertension-associated dysfunction of NO-induced relaxation in corpus cavernosum smooth muscle possibly via inhibition of the Rho-Rho kinase pathway and activation of NO-eNOS pathway in the SHR.


Urologia Internationalis | 2012

Fas expression in renal cell carcinoma accurately predicts patient survival after radical nephrectomy.

Takehiro Sejima; Shuichi Morizane; Nobuyuki Hinata; Akihisa Yao; Tadahiro Isoyama; Motoaki Saito; Atsushi Takenaka

Objectives: To investigate Fas, Fas ligand (FasL) and Bcl-2 expression, which are considered to be important apoptotic regulatory factors in renal cell carcinomas (RCCs). Patients and Methods: mRNA quantification and immunohistochemistry allowed for the determination of the expression of these three factors in surgically resected tumors from 82 patients with RCC. The correlation of protein and gene expression with more than 10 years of survival data following nephrectomy (along with clinical and pathologic parameters) was analyzed using uni- and multivariate statistical models. Results: A significantly poorer outcome was observed in patients with tumors expressing high levels of Fas mRNA in the multivariate analysis (p = 0.0002). In addition, patient survival was significantly worse in FasL mRNA-positive tumor cases when compared with FasL mRNA-negative cases (p = 0.0345). Ten cases relapsed more than 5 years after nephrectomy. Among them, the tumors of 8 cases (80%) did not express FasL mRNA. Analysis of Bcl-2 did not show statistical significance of Bcl-2 expression as a prognostic indicator. Conclusions: The data suggest that pronounced Fas expression is a surrogate biomarker of active cancer cell proliferation. Given the FasL tumor counterattack theory, FasL overexpression in RCC may be one of the host immune deficiencies, consequently leading to poor prognosis.


International Journal of Urology | 2015

High neutrophil‐to‐lymphocyte ratio predicts poor clinical outcome in patients with castration‐resistant prostate cancer treated with docetaxel chemotherapy

Akihisa Yao; Takehiro Sejima; Hideto Iwamoto; Toshihiko Masago; Shuichi Morizane; Masashi Honda; Atsushi Takenaka

To evaluate the prognostic significance of the neutrophil‐to‐lymphocyte ratio in patients receiving chemotherapy with docetaxel for castration‐resistant prostate cancer.


Journal of Andrology | 2014

Blocking of the ATP sensitive potassium channel ameliorates the ischaemia‐reperfusion injury in the rat testis

Shogo Shimizu; Ryo Oikawa; Panagiota Tsounapi; Keiji Inoue; Takahiro Shimizu; K. Tanaka; Darryl T. Martin; Masashi Honda; Takehiro Sejima; Shuhei Tomita; Motoaki Saito

There is increasing evidence that the effects of administered ATP sensitive potassium (KATP) channel openers or blockers during ischaemia are still controversial in many organs/tissues. Testicular torsion detorsion which causes ischaemia‐reperfusion (IR) injury, cannot be predicted, thus an effective drug should be administered during or after the ischaemia. The aim of this study was to examine whether the administration of KATP channel openers or blockers during ischaemia ameliorates IR injury in the testis. Eight‐week‐old male Sprague–Dawley rats were subjected to 2 h right testicular ischaemia followed by 24 h reperfusion. The selective mitochondrial (mito) KATP channel blocker, 5‐hydroxydecanoate (5‐HD) (40 mg/kg), the non‐selective KATP channel blocker glibenclamide (5 mg/kg), the selective mito KATP channel opener diazoxide (10 mg/kg) and the non‐selective KATP channel opener cromakalim (300 μg/kg) were administered intraperitoneally 15 min prior to the ischaemia or 75 min after the induction of ischaemia. Tissue damage was evaluated by malondialdehyde concentration, myeloperoxidase activity, histological evaluation and TdT‐mediated dUTP nick end labelling assay in the testis. There was a significant increase in oxidative stress, neutrophil infiltration, histological damage and apoptosis in the testicular IR model. A significant reduction in the testicular IR injury was observed with the administration of glibenclamide, but not 5‐HD, diazoxide or cromakalim during ischaemia. The administration of non‐selective KATP channel blocker glibenclamide ameliorated the testicular IR injury. On the other hand, the selective mito KATP channel blocker, 5‐HD and KATP channel openers did not reduce the testicular IR injury. These data suggest that blocking of the membrane KATP channel may have a protective effect during the testicular ischaemia. Glibenclamide could be an effective drug to manage the post‐ischaemic injury caused by the testicular torsion‐detorsion.


The Journal of Urology | 2012

Detailed Histological Investigation of the Female Urethra: Application to Radical Cystectomy

Nobuyuki Hinata; Gen Murakami; Shin-ichi Abe; Masashi Honda; Tadahiro Isoyama; Takehiro Sejima; Atsushi Takenaka

PURPOSE We histologically examined the urethral anatomy to assess whether the surgical procedure for radical cystectomy should be modified in females. MATERIALS AND METHODS Anatomical and histological studies were performed on 20 adult female cadavers. Semiserial sections were processed for histological examination and immunohistochemistry. To assess the clinical value of the antegrade approach we examined blood loss and function in 12 consecutive patients who underwent radical cystectomy by this approach. RESULTS Vaginal wall smooth muscle contributed to urethral wall formation, in addition to a thin layer of proper urethral smooth muscle, particularly when the bladder detrusor was poorly developed or degenerated. The middle urethra was attached tightly to the vaginal smooth muscles with abundant veins running at the interface. The urethral sphincter and its inferoposterior continuation (urethrovaginal sphincter) were embedded in the elastic fiber rich perineal membrane. The membrane was U shaped, wrapping around the anterior aspect of the middle urethra and extending posterior along the distal vagina to end at the lateral extension of the perineal body near the external anal sphincter. Mean estimated blood loss was 965 ml. Of patients who received a neobladder hypercontinence was observed in 14.3% and 57.1% achieved continence. CONCLUSIONS There is topographical variation in the anatomy of tissues surrounding the female urethra. Care should be taken when dissecting the tissues dorsal or lateral to the urethra. The antegrade approach is useful since the urethra can be dissected under direct vision and traction can be applied to these structures.

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