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101.
Fas (CD95) is a cell surface glycoprotein that mediates apoptotic cell death when cross-linked with agonistic anti-Fas monoclonal antibodies (MAbs) or the endogenous Fas ligand. In this study, we investigated the in vitro biological properties of a panel of anti-human Fas MAbs. We found that five anti-Fas MAbs of IgG1 subclass (B.E28, B.G30, B.L25, DX2, and B.G34) induced marked apoptotic cell death in Fas-expressing leukemia cells, although this killing was delayed when compared to the cytolytic effect mediated by the prototypic anti-Fas MAb of IgM subclass (clone CH-11). On the other hand, four clones (ZB4, B.G27, B.D29, and B.K14) efficiently blocked apoptotic cell death induced by the CH-11 MAb or Fas ligand. The ability of these MAbs to inhibit cell death appeared to correlate with their relative affinity for the Fas molecule. Furthermore, different clones recognized the same epitope and elicited different effects (induction or inhibition of cell killing); conversely, different clones elicited the same effect but recognized different epitopes. These results suggest that the different biological effects of anti-Fas MAbs would not be mediated in an epitope-restricted manner. The relative binding affinity might correlate to some extent with the biological properties of the MAb. 相似文献
102.
After examining the in vitro cell-kill kinetics of various anticancer drugs by using cultured human cell lines, Shimoyama et al. classified the drugs into two groups according to the types of action: 1) type-I drugs (cytocidal and concentration-dependent action) such as alkylating agents and anticancer antibiotics; 2) type-II drugs (cytostatic and time-dependent action) such as antimetabolites, Vinca alkaloids and L-asparaginase. In the present paper, we will present a rational basis for such a classification by using cell-kill pharmacodynamic models, and consider the optimal dosage regimen depending on the type of drugs by combining the cell-kill kinetic and pharmacokinetic models. In these models, classification of the drugs depends on whether the cell population is kinetically homogenous or not. It is assumed that cell population is homogenous for type-I drugs and there exist both drug sensitive and insensitive cell populations for type-II drugs. The concentration (or dose)-time-cell survival curves in both in vitro and in vivo, which are simulated based on the kinetic models, are consistent with the experimental data found in the literature. Further analysis on the optimal dose regimen according to these kinetic models clarified that the type-I drugs showed a similar cell-kill effect irrespective of the mode of administration as long as the area under the plasma unbound concentration curves (AUCp, free) is kept constant, while the type-II drugs are more effective by multiple dosing or infusion regimen than single administration of a large dose of drugs. In other words, the extents of AUCp, free and the residence time in the plasma (above certain concentrations of drugs) are determinants of the in vivo cell-kill effects of type-I drugs and type-II drugs, respectively. If the pharmacokinetics of newly developed anticancer drugs in human are predicted from the animal data according to the so-called "animal scale-up" technique and combined with the in vitro cell-kill kinetic data by the use of proposed kinetic models, one may obtain not only the optimal dosage regimen but also good screening systems for truly active drugs for the treatment of human cancer. 相似文献
103.
Naoki Fujita Shingo Hatakeyama Kazutaka Okita Masaki Momota Takuma Narita Yuki Tobisawa Tohru Yoneyama Hayato Yamamoto Atsushi Imai Hiroyuki Ito Takahiro Yoneyama Yasuhiro Hashimoto Kazuaki Yoshikawa Chikara Ohyama 《Urologic oncology》2021,39(3):191.e9-191.e16
ObjectivesTo investigate the impact of chronic kidney disease (CKD) on oncological outcomes in patients with high-risk non-muscle invasive bladder cancer (NMIBC) who underwent adjuvant induction bacillus Calmette-Guérin (BCG) therapy after transurethral resection of bladder tumor (TURBT).Materials and MethodsWe conducted a multi-institutional retrospective study assessing 209 patients with high-risk NMIBC who underwent TURBT and subsequent adjuvant induction BCG therapy from December 1998 to April 2019. Patients were divided into 2 groups: those with preoperative estimated glomerular filtration rate (eGFR) ≥ 60 ml/min/1.73 m2 (non-CKD group), and those with eGFR < 60 ml/min/1.73 m2 (CKD group). Primary endpoints were intravesical recurrence-free survival (RFS) and muscle-invasive bladder cancer (MIBC)-free survival. Background-adjusted multivariate analyses with the inverse probability of treatment weighting (IPTW) method using the propensity score were performed to evaluate the impact of CKD on intravesical RFS, MIBC-free survival, metastasis-free survival, cancer-specific survival, and overall survival. Moreover, multivariable analyses were performed to assess the impact of CKD on intravesical recurrence and MIBC progression, adjusting for the competing risk of death using the Fine-Gray competing risk regression model.ResultsMedian age and follow-up period after TURBT were 72 years and 45 months, respectively. Of 209 patients, 71 (34%) were diagnosed with CKD before TURBT. Background-adjusted multivariate analyses with the IPTW method indicated that CKD was significantly associated with shorter intravesical RFS, MIBC-free survival, metastasis-free survival, cancer-specific survival, and overall survival. In the Fine-Gray competing risk regression model, CKD showed significantly higher probabilities of intravesical recurrence and MIBC progression, with an adjusted subdistribution hazard ratio of 1.886 (95% confidence interval 1.069–3.330, P = 0.028) and 3.740 (95% confidence interval 1.060–13.20, P = 0.040), respectively.ConclusionsCKD presents a risk factor of poor oncological outcomes in patients with high-risk NMIBC who underwent adjuvant induction BCG therapy after TURBT. 相似文献
104.
Kyo Togashi Shingo Hatakeyama Yuta Kojima Masaki Momota Takuma Narita Hiromichi Iwamura Itsuto Hamano Tomoko Hamaya Naoki Fujita Teppei Okamoto Tohru Yoneyama Hayato Yamamoto Takahiro Yoneyama Yasuhiro Hashimoto Chikara Ohyama 《Urologic oncology》2021,39(3):192.e7-192.e14
ObjectivesWe aimed to evaluate the effect of frailty on health-related quality-of-life (HRQOL) and lower urinary symptoms (LUTS) following robot-assisted radical prostatectomy (RARP) in patients with prostate cancer (CaP).Materials and MethodsWe longitudinally evaluated geriatric 8 (G8), HRQOL, and LUTS for 12 months in 118 patients with RARP from January 2017 to April 2020. Patients were divided into frail (G8 ≤14) and nonfrail (G8 >14) groups. We compared the effect of frailty on HRQOL and LUTS between the frail and nonfrail groups before and 12 months after RARP.ResultsThe median age of patients was 68 years. The number of patients in the frail and nonfrail groups were 41 and 77, respectively. No significant difference in patients’ background was observed between the groups, except for the presence of cardiovascular disease (22% vs. 7.8%, P = 0.041). There was no significant difference in HRQOLs and LUTS between the groups at baseline. Similarly, HRQOLs, LUTS, and pad-free continence rates were not significantly different between the groups at 12 months after RARP. In the nonfrail group, LUTS at 12 months following RARP significantly improved compared to those at the baseline, but it did not significantly improve in the frail group. Multivariable logistic regression analysis demonstrated that frailty was not significantly associated with LUTS worsening.ConclusionsFrailty was not significantly associated with the worsening of HRQOL, LUTS, and pad-free continence rates in patients treated with RARP. 相似文献
105.
Hirotaka Horiguchi Shingo Hatakeyama Tohru Yoneyama Mihoko Sutoh Yoneyama Toshikazu Tanaka Naoki Fujita Teppei Okamoto Hayato Yamamoto Takahiro Yoneyama Tadashi Yoshizawa Yasuhiro Hashimoto Toshiaki Kawaguchi Chikara Ohyama 《Urologic oncology》2021,39(4):238.e9-238.e17
ObjectivesTo investigate the association between Ki67 index and programmed death-ligand 1 (PD-L1) expression in muscle-invasive bladder cancer (MIBC) patients after RC.Materials and MethodsWe retrospectively evaluated 262 MIBC patients treated with RC between April 2004 and April 2020. The impact of Ki67 index and PD-L1 expression on prognosis was evaluated by univariate Cox regression analysis. In addition, a pathomolecular risk score, including Ki67 and PD-L1, was developed to predict prognosis and pathological factors. We also evaluated the link between the Ki67 index and PD-L1 under the IL-6 stimulation in the bladder cancer cell lines of T24 and 5637 cells.ResultsThe median age and follow-up period was 69 years and 52 months, respectively. Ki67 index and PD-L1 expression were significantly associated with tumor recurrence. Univariate Cox regression analysis showed that pT3–4, mixed histology, lymphovascular invasion positive (LVI+), pN+, Ki67-high (>17%), and PD-L1+ were significantly associated with recurrence-free survival (RFS). The pathomolecular risk score was developed using resection margin+ (1 point), mixed histology (1 point), LVI+ (1 point), pN+ (1 point), and Ki67-high (1 point). RFS and overall survival were significantly shorter in patients with higher pathomolecular risk scores (>1) than in those with lower risk scores (≤1). Cell proliferation was significantly increased in the T24 and 5637 cells under the IL-6 stimulation, while PD-L1 expression was not.ConclusionsA significant effect of Ki67-high and PD-L1 expression on poor prognosis was observed in patients with MIBC. Further studies are necessary to elucidate the precise mechanisms of cell proliferation and PD-L1 expression in patients with MIBC. 相似文献
106.
Masayuki Tomioka Tohru Yoneyama Yuki Tobisawa Kota Kawase Chie Nakai Manabu Takai Daiki Kato Koji Iinuma Keita Nakane Kosuke Mizutani Yasuhiro Hashimoto Takuya Koie 《Translational andrology and urology》2021,10(3):1192
BackgroundAlthough the patients with muscle-invasive bladder cancer (MIBC) generally have poor prognosis, the utility of these biomarkers for the prediction of oncological outcomes in MIBC has not been completely explored. Ghrelin regulates processes associated with cancer, including cell proliferation, apoptosis, cell migration, cell invasion, and angiogenesis. Thus, we aimed to evaluate the impact of serum ghrelin levels on survival in MIBC.MethodsIn this study, we reviewed the clinical and pathological records of 56 patients who were diagnosed with MIBC between November 2015 and November 2019 at Gifu and Hirosaki University Hospitals. We focused on 27 patients who had received chemotherapy and collected blood samples before and after chemotherapy. Blood samples were collected before chemotherapy and after completing two cycles of chemotherapy. Serum acyl (AG) and desacyl ghrelin (DG) were measured using AG and DG enzyme-linked immunosorbent assay kits (SCETI, Tokyo, Japan), respectively.ResultsThe 3-year overall and progression-free survival (PFS) rates were 82.9% and 68.3%, respectively. According to the AG level after chemotherapy, the 3-year PFS rates were 77.5% and 53.0% in patients with AG levels ≥1.34 and <1.34 pg/mL, respectively (P=0.038). With regard to DG levels after chemotherapy, the 3-year PFS rates were 90.9% and 43.3% in patients with DG levels <92.3 and ≥92.3 pg/mL, respectively (P=0.039). On multivariate analysis, serum AG levels were significantly associated with PFS.ConclusionsThis study suggested the usefulness of the ghrelin as a prognostic predictor of PFS in patients with MIBC. 相似文献
107.
Bibek Dutta Taichi Asami Tohru Imatomi Kento Igarashi Kento Nagata Tomomi Watanabe-Asaka Takako Yasuda Shoji Oda Manfred Shartl Hiroshi Mitani 《Journal of radiation research》2021,62(1):12
Transgenic expression in medaka of the Xiphophorus oncogene xmrk, under a pigment cell specific mitf promoter, induces hyperpigmentation and pigment cell tumors. In this study, we crossed the Hd-rR and HNI inbred strains because complete genome information is readily available for molecular and genetic analysis. We prepared an Hd-rR (p53+/−, p53−/−) and Hd-rR HNI hybrid (p53+/−) fish-based xmrk model system to study the progression of pigment cells from hyperpigmentation to malignant tumors on different genetic backgrounds. In all strains examined, most of the initial hyperpigmentation occurred in the posterior region. On the Hd-rR background, mitf:xmrk-induced tumorigenesis was less frequent in p53+/− fish than in p53−/− fish. The incidence of hyperpigmentation was more frequent in Hd-rR/HNI hybrids than in Hd-rR homozygotes; however, the frequency of malignant tumors was low, which suggested the presence of a tumor suppressor in HNI genetic background fish. The effects on tumorigenesis in xmrk-transgenic immature medaka of a single 1.3 Gy irradiation was assessed by quantifying tumor progression over 4 consecutive months. The results demonstrate that irradiation has a different level of suppressive effect on the frequency of hyperpigmentation in purebred Hd-rR compared with hybrids. 相似文献
108.
Koji Inaba Keisuke Tsuchida Tairo Kashihara Rei Umezawa Kana Takahashi Kae Okuma Naoya Murakami Yoshinori Ito Hiroshi Igaki Minako Sumi Yuko Nakayama Yasuo Shinoda Tomohiko Hara Yoshiyuki Matsui Motokiyo Komiyama Hiroyuki Fujimoto Jun Itami 《Journal of radiation research》2021,62(3):511
Although systemic therapy is the standard treatment for metastatic prostate cancer, a randomized controlled trial showed radiotherapy to the prostate improved overall survival of metastatic prostate cancer patients with the low metastatic burden. Additionally, a randomized phase II trial showed that metastasis-directed therapy for oligo-recurrent prostate cancer improved androgen-deprivation therapy (ADT)-free survival. Therefore, administering radiotherapy to both prostate and metastatic regions might result in better outcomes. Thus, we report the treatment results of radiotherapy to both prostate and metastatic regions. Our institutional database was searched for patients who received radiotherapy to the prostate and metastatic regions. We summarized patient characteristics and treatment efficacy and performed statistical analysis to find possible prognostic factors. A total of 35 patients were included in this study. The median age was 66 years, and the median initial prostate-specific antigen (PSA) level was 32 ng/ml. The Gleason score was 7 in 10 patients, 8 in 13 patients, and 9 in 12 patients. The median radiotherapy dose was 72 Gy to the prostate and 50 Gy to the metastatic bone region. The 8-year overall survival, cause-specific survival, progression-free survival, and freedom from biochemical failure rate were 81, 85, 53, and 57%. Among the 35 patients, 12 were disease-free even after ADT was discontinued. In selected patients with metastatic prostate cancer, ADT and radiotherapy to the prostate and metastatic sites were effective. Patients with good response to ADT may benefit from radiotherapy to both prostate and metastatic regions. 相似文献
109.
Expression of membrane-bound and soluble receptor activator of NF-kappaB ligand (RANKL) in human T cells 总被引:1,自引:0,他引:1
The receptor activator of NF-kappaB ligand (RANKL) and its receptor RANK are critical regulators for immune responses as well as bone remodeling. RANKL is a type II transmembrane protein that has two forms-a membrane-anchored protein and a secreted protein. In this report, we demonstrate for the first time the kinetical expression of two forms of RANKL in human T cells using two monoclonal antibodies (mAbs) against human RANKL, which we newly derived. Freshly isolated T cells rarely expressed mRANKL, while the activation of T cells induced a substantial but minimal level of mRANKL as well as the accumulation of considerable amounts of sRANKL. The addition of the metalloprotease inhibitor KB-R8301 efficiently suppressed the release of sRANKL from activated T cells or RANKL-transfectants, and reciprocally enhanced the mRANKL expression. The membrane form of RANKL was also expressed on the infiltrating T cells in the rheumatoid synovial fluid and in the gingival tissues of patients with periodontitis. Our results demonstrate that the expression of mRANKL on T cells is strictly limited, and the majority of RANKL protein produced by T cells may be active in the soluble form after shedding. The mAbs that were derived in this study may be useful for investigating the regulation and function of RANKL in immune responses and bone remodeling. 相似文献
110.
Photoreceptor differentiation of retinoblastoma: An electron microscopic study of 29 retinoblastomas
Yasuo Tajima Shigeru Munakata Yasuo Ishida Tohru Nakajima Isamu Sugano Koichi Nagao Kensei Minoda Yoichiro Kondo 《Pathology international》1994,44(12):837-843
Retinoblastomas exhibit a unique form of differentiation to produce cell elements similar to those seen in a photoreceptor cell. An ultrastructural study was performed on 29 cases of retinoblastoma to further clarify the cytologic characteristics of the tumor cells. The age of the retinoblastomas averaged 17.1 months and the tumor cells showing photo-receptor differentiation were demonstrated in 10 cases (35%). The findings were especially notable in retinoblastomas with Flexner-Wintersteiner rosette formation (seven cases, 28%). Similar photoreceptor differentiation was also evident in solid cell clusters without rosette formation (four cases, 14%). The presence of photoreceptor elements was assumed to be significantly frequent both in Flexner-Wintersteiner rosettes and in the solid cell clusters. The cell cytoplasm also showed proliferation of long mitochondria and microtubules, reflecting photoreceptor differentiation. The hereditary-type retinoblastoma showed more advanced cell differentiation than the non-hereditary type. Photoreceptor differentiated retinoblastoma showed rather indolent growth compared with the undifferentiated type, and the former can expect a curative treatment by operation. These observations provide additional findings of the biological nature of retinoblastomas. 相似文献