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41.
Crk (C10 regulator of kinase) adaptor proteins are highly expressed in many types of human cancers and often contribute to aggressive cancer phenotypes. Crk II, a member of CRK family, has been reported to regulate cell migration and metastasis in breast cancer cells. However, its role in other cancer types has not been reported. In this study, we investigated the molecular function of Crk II in prostate cancer (PCa) cells (CWR-22rv1) in vitro and using a mouse tumor model. Results showed that Crk II knockdown by shRNA-mediated silencing (Crk II-shRNA) in the PCa cells significantly inhibited both cancer cell migration and invasion in cell culture study. Crk II-shRNA cancer cells also significantly decreased colony formation in vitro, but had no significant reduction of tumor volume after 4 weeks of cancer cell xenografting in vivo when compared to the scramble control. Interestingly, Crk II-shRNA cancer cells showed a greatly reduced level of insulin-like growth factor 1 receptor (IGF-1R) and decreased signaling of the IGF-1R/PI3K/Akt axis upon IGF-1 ligand stimulation. A close interaction between Crk II and IGF-1R was demonstrated upon co-immunoprecipitation of IGF-1R with Crk II protein. Further, treatment of cells with either proteosomal degradation or protein synthesis inhibitor showed higher proportion of ubiquitin-associated IGF-1R and faster degradation of IGF-1R in Crk II-shRNA cells in comparison with that in the control cancer cells. Taken together, these data suggest that Crk II plays an important role in the regulation of IGF-1R protein stability and affects downstream of IGF-1R signaling pathways. Therefore, targeting Crk-II can block IGF-1R growth signaling and suppress cancer cell invasion and progression.  相似文献   
42.
T淋巴细胞受体(TCRs)在抗原识别免疫应答中作用重要,其多样性与宿主免疫反应及肿瘤预后判断密切相关。目的:采用高通量测序技术研究前列腺癌组织和癌旁组织中T细胞受体(TCR)克隆多样性及其克隆序列。方法:收集5例PC患者的癌组织和癌旁组织,提取DNA后经多重PCR技术对TCRβ链CDR3区进行扩增。用Illumina MiSeq进行测序,经过数据处理和比对分析,比较前列腺癌组织TCR CDR3组库的组成特征。结果:前列腺癌组织具有更高程度的克隆百分比和较高的高度扩增克隆比HEC(HEC:频率样本总读数的0. 5%的TCR克隆),并获得了24对在癌组织样本中差异表达的V-J基因组合、16对在癌旁组织样本中差异表达的V-J基因组合。结论:前列腺癌组织与癌旁组织均存在差异性的V-J基因组合以及高克隆表达的HEC,其中癌组织样品具有更高的HEC。PC发生发展对免疫学研究提供了新的数据,对PC免疫监视、T细胞受体变异标志等研究提供了参考,对以后继续研究打下了基础。  相似文献   
43.
AimThe purpose of this study is to evaluate the long term tolerability of hypofractionated helical tomotherapy (HT) in localized prostate cancer patients.BackgroundPrevious hypofractionated schedules with conventional RT were associated with excessive toxicity, likely due to inadequate sophistication of treatment delivery. There are few data about late toxicity after HT.Materials and methodsWe evaluated 38 patients with primary adenocarcinoma of the prostate. There were 9 (24%), 15 (39%), and 14 (37%) patients with high, intermediate, and low risk, respectively. Patients were treated with hypofractionated HT from May 2008 to February 2011. Hypofractionation regimens included: 68.04 Gy at 2.52 Gy/fraction (N = 25; 66%), 70 Gy at 2.5 Gy/fraction (N = 4; 11%) and 70.2 Gy at 2.6 Gy/fraction (N = 9; 23%). Late genitourinary (GU) and gastrointestinal (GI) toxicity was scored using the Radiation Therapy Oncology Group scoring system.ResultsMedian age at diagnosis was 70 years (range 49–80) and median follow-up, 5.8 years. Late grade 1, 2 and 3 GI toxicity were 13%, 24%, and 2.6%, respectively. Late grade 1, 2, 3 GU toxicity were 29%, 21%, and 8%, respectively. Sexual toxicity was evaluated in 19 patients to be grade 1, 2 in 11% and grade 3 in 16%. Multivariate analysis showed that patients with higher values of rectum V50 associated with late GI toxicity (P = 0.025). Patients with PSA ≤8 (P = 0.048) or comorbidities (P = 0.013) at diagnosis were associated with higher late GU toxicity. Additionally, PSA ≤8 also associated with moderate (grade ≥2) late GU toxicity in the multivariate analysis (P = 0.028).ConclusionsHypofractionated HT can be delivered safely with limited rates of moderate and severe late toxicity. The proportion of the rectum that receives a moderate and high dose, having comorbidities, and PSA at diagnosis seem to associate with long term toxicity.  相似文献   
44.
AimTo study the dosimetric impact of statistical uncertainty (SU) per plan on Monte Carlo (MC) calculation in Monaco? treatment planning system (TPS) during volumetric modulated arc therapy (VMAT) for three different clinical cases.BackgroundDuring MC calculation SU is an important factor to decide dose calculation accuracy and calculation time. It is necessary to evaluate optimal acceptance of SU for quality plan with reduced calculation time.Materials and methodsThree different clinical cases as the lung, larynx, and prostate treated using VMAT technique were chosen. Plans were generated with Monaco? V5.11 TPS with 2% statistical uncertainty. By keeping all other parameters constant, plans were recalculated by varying SU, 0.5%, 1%, 2%, 3%, 4%, and 5%. For plan evaluation, conformity index (CI), homogeneity index (HI), dose coverage to PTV, organ at risk (OAR) dose, normal tissue receiving dose ≥5 Gy and ≥10 Gy, integral dose (NTID), calculation time, gamma pass rate, calculation reproducibility and energy dependency were analyzed.ResultsCI and HI improve as SU increases from 0.5% to 5%. No significant dose difference was observed in dose coverage to PTV, OAR doses, normal tissue receiving dose ≥5 Gy and ≥10 Gy and NTID. Increase of SU showed decrease in calculation time, gamma pass rate and increase in PTV max dose. No dose difference was seen in calculation reproducibility and dependent on energy.ConclusionFor VMAT plans, SU can be accepted from 1% to 3% per plan with reduced calculation time without compromising plan quality and deliverability by accepting variations in point dose within the target.  相似文献   
45.
AimTo analyse the efficacy and toxicity of postprostatectomy SRT in patients with a BCR evaluated with mpMRI.BackgroundMultiparametric magnetic resonance imaging (mpMRI) has the ability to detect the site of pelvic recurrence in patients with biochemical recurrence (BCR) after radical prostatectomy (RP). However, we do not know the oncological outcomes of mpMRI-guided savage radiotherapy (SRT).ResultsLocal, lymph node, and pelvic bone recurrence was observed in 13, 4 and 2 patients, respectively. PSA levels were significantly lower in patients with negative mpMRI (0.4 ng/mL [0.4]) vs. positive mpMRI (2.2 ng/mL [4.1], p = 0.003). Median planning target volume doses in patients with visible vs. non-visible recurrences were 76 Gy vs. 70 Gy. Overall, mean follow-up was 41 months (6–81). Biochemical relapse-free survival (bRFS) at 3 years was 82.3% and 82.5%, respectively, for the negative and positive mpMRI groups (p = 0.800). Three-year rates of late grade ≥2 urinary and rectal toxicity were 14.8% and 1.9%, respectively; all but one patient recovered without sequelae.ConclusionSRT to the macroscopic recurrence identified by mpMRI is a feasible and well-tolerated option. In this study, there were no differences in bRFS between MRI-positive and MRI-negative patients, indicating effective targeting of MRI-positive lesions.  相似文献   
46.
Study the effect of stachydrine hydrochloride to prostatic hyperplasia in mice which made of the urogenital sinus implantation. KM male mices were selected.The group was given the respective drugs for gavage, the group of BG and MG were given the distilled water which the same amount as the drugs group for 21 consecutive days. The level of DHT, ACP, Non PACP were measured in serum, the average wet weight of the prostate and prostate index were calculated, the expression of bFGF, EGF, IGF-I, TGF-β in prostate tissue were measured, the pathological changes of the prostate, kidney, thymus, spleen were observed by HE staining. Compared with MG, stachydrine hydrochloride high (SHH), medium (SHM) and low (SHL) group could reduced the level of DHT and PACP in serum significantly (P < 0.01); SHM and SHL could increased the express of TGF-β1 significantly (P < 0.05); SHH, SHM, SHL could reduced the express of EGF significantly (P < 0.01); SHM could reduced the express of IGF-Ⅰ significantly (P < 0.01); Compared with MG, SHH, SHM, SHL could reduced the pathological changes of prostate significantly (P < 0.01); FG could reduced the kidney pathological changes significantly (P < 0.01). Stachydrine hydrochloric had no significant effect on the kidney. Stachydrine hydrochloride had the effect of improve thymus, spleen pathological changes. Stachydrine hydrochloride has a good inhibition effect on prostatic hyperplasia model in mices.  相似文献   
47.
Prostate cancer (PC) is the second most commonly occurring cancer in men. Conventional chemotherapy has wide variety of disadvantages such as high systemic toxicity and low selectivity. Targeted drug delivery is a promising approach to decrease side effects of therapy. Prostate specific membrane antigen (PSMA) is overexpressed in prostate cancer cells while low level of expression is observed in normal cells. In this study we describe the development of Glu-urea-Lys based PSMA-targeting conjugates with paclitaxel. A series of new PSMA targeting conjugates with paclitaxel was designed and synthesized. The cytotoxicity of conjugates was evaluated against prostate (LNCaP, 22Rv1 and PC-3) and non-prostate (Hek293T, VA13, A549 and MCF-7) cell lines. The most promising conjugate 21 was examined in vivo using 22Rv1 xenograft mice model. It demonstrated good efficiency comparable with paclitaxel, while reduced toxicity. 3D molecular docking study was also performed to understand underlying mechanism of binding and further optimization of the linker substructure and conjugates structure for improving the target affinity. These conjugates may be useful for further design of novel PSMA targeting delivery systems for PC.  相似文献   
48.
BackgroundMartinique has one of the highest incidences of prostate cancer (PCa) worldwide. We analysed overall survival (OS) among patients with PCa in Martinique, using data from a population-based cancer registry between 2005 and 2014.MethodsThe log-rank test was used to assess the statistical differences between survival curves according to age at diagnosis, risk of disease progression including Gleason score, stage at diagnosis and Prostate Specific Antigen (PSA). A multivariable Cox model was constructed to identify independent prognostic factors for OS.ResultsA total of 5045 patients were included with a mean age at diagnosis of 68.1±9.0 years [36.0 – 98.0 years]. Clinical stage was analysed in 4999 (99.1% of overall), 19.5% were at low risk, 34.7% intermediate and 36.9% at high risk. In our study, 8.9% of patients with available stage at diagnosis, were regional/metastatic cancers. Median PSA level at diagnosis was 10.4 ng/mL. High-risk PCa was more frequent in patients aged 65-74 and ≥75 years as compared to those aged <65 years (36.6% and 48.8% versus 28.7% respectively; p<0.0001). One-year OS was 96.3%, 5-year OS was 83.4 and 10-year OS was 65.0%. Median survival was not reached in the whole cohort. High-risk PCa (HR=2.32; p<0.0001), regional/metastatic stage (HR= 9.51; p<0.0001) and older age (65-74 and ≥75 years - respectively HR=1.70; and HR=3.38), were independent prognostic factors for OS (p<0.0001).ConclusionThis study provides long term data that may be useful in making cancer management decisions for patients with PCa in Martinique.  相似文献   
49.
目的探讨超声引导下前列腺穿刺联合外周血循环肿瘤细胞(CTCs)检测对前列腺癌预后的预测效果。方法选取2011年1月至2017年12月期间于郑州大学第二附属医院收治的83例前列腺癌患者为研究对象,全部患者均根据超声引导下经直肠前列腺穿刺活检术确诊为前列腺癌,检测病理标本中CK34BE12、p63、α-甲酰基辅酶A消旋酶(AMACR)等免疫标志物的表达状况,并采用Cell Search细胞搜索系统检测外周血CTCs的数量,据此分为阳性组(≥5个/7.5 ml)和阴性组(<5个/7.5 ml)。分析穿刺组织中免疫标志物表达状况、外周血CTCs计数与患者临床病理特征、生存状况的相关性。各标志物的阳性例数、Gleason评分>7分的比例、TNM分期等定性资料的比较采用x^2检验或Fisher确切概率法,年龄、血常规、凝血功能、肝功能、PSA水平等定量资料的比较采用t检验。采用Kaplan-Meier法进行生存分析,采用多因素Cox比例风险回归模型分析患者预后的预测因素。结果(1)全部患者中外周血CTCs、穿刺组织中CK34BE12、p63、AMACR的阳性率分别为31.33、3.61、3.61、86.75。CTCs阳性组的AMACR阳性率为100.00,高于CTCs阴性组的80.70,差异有统计学意义(x^2=4.227,P<0.05)。(2)AMACR阳性组患者的血红蛋白(HB)低于AMACR阴性组[(123.66±13.33)g/L比(134.89±20.08)g/L,t=2.420,P=0.018],血小板(PLT)、血清谷丙转氨酶、D-二聚体(DD)、前列腺特异抗原(PSA)水平、Gleason评分>7分的比例均高于AMACR阴性组[(197.23±36.98)×10^9/L比(172.83±33.33)×10^9/L,t=2.062,P=0.042;(38.80±10.03)U/L比(31.46±7.83)U/L,t=2.317,P=0.023;(255.00±38.80)μg/L比(220.81±30.99)μg/L,t=2.785,P=0.007;(26.60±12.23)ng/ml比(17.90±8.88)ng/ml,t=2.263,P=0.026;45.83比9.09,x^2=3.916,P=0.048],差异有统计学意义(P<0.05)。CTCs阳性组患者的HB低于CTCs阴性组[(121.69±15.89)g/L比(132.73±18.85)g/L,t=2.767,P=0.007],血清碱性磷酸酶、DD、PSA水平、Gleason评分>7分、T3~T4期、M1期的比例均高于CTCs阴性组[(105.69±30.56)U/L比(88.89±35.58)U/L,t=2.205,P=0.030;(256.63±35.86)μg/L比(236.98±33.30)μg/L,t=2.368,P=0.020;(30.09±11.89)ng/ml比(23.33±10.99)ng/ml,t=2.533,P=0.013;57.69比33.33,x^2=4.381,P=0.036;30.77比8.77,x^2=4.981,P=0.026;50.00比17.54,x^2=9.390,P=0.002],差异有统计学意义(P<0.05)。(3)全部患者的中位生存时间为58.33个月,1、3、5年的生存率分别为88.95、51.81、30.12。AMACR阳性组、CTCs阳性组患者的中位生存时间为40.93、36.93个月,低于AMACR阴性组、CTCs阴性组的66.66、69.56个月,差异有统计学意义(P<0.05)。多因素Cox比例风险回归模型分析结果表明,Gleason评分>7分、M1期、AMACR阳性、CTCs阳性是患者死亡的独立危险因素(HR=1.883、3.666、2.009、2.923,P<0.05)。结论超声引导下前列腺穿刺联合外周血CTCs检测对前列腺癌患者的预后具有重要的预测价值,临床上可根据穿刺组织中AMACR表达水平和外周血CTCs计数进行预后的综合分析。  相似文献   
50.
BackgroundTo examine changes in prostate cancer incidence and mortality rates, and 5-year relative survival, in relation to changes in the rate of prostate specific antigen (PSA) screening tests and the use of radical prostatectomy (RP) in the Australian population.MethodsProstate cancer stage-specific incidence rates, 5-year relative survival and mortality rates were estimated using New South Wales Cancer Registry data. PSA screening test rates and RP/Incidence ratios were estimated from Medicare Benefits Schedule claims data. We used multiple imputation to impute stage for cases with “unknown” stage at diagnosis. Annual percentage changes (APC) in rates were estimated using Joinpoint regression.ResultsTrends in the age-standardized incidence rates for localized disease largely mirrored the trends in PSA screening test rates, with a substantial ‘spike’ in the rates occurring in 1994, followed by a second ‘spike’ in 2008, and then a significant decrease from 2008 to 2015 (APC −6.7, 95% CI −8.2, −5.1). Increasing trends in incidence rates were observed for regional stage from the early 2000s, while decreasing or stable trends were observed for distant stage since 1993. The overall RP/Incidence ratio increased from 1998 to 2003 (APC 9.6, 95% CI 3.8, 15.6), then remained relatively stable to 2015. The overall 5-year relative survival for prostate cancer increased from 58.4% (95% CI: 55.0–61.7%) in 1981–1985 to 91.3% (95% CI: 90.5–92.1%) in 2011–2015. Prostate cancer mortality rates decreased from 1990 onwards (1990–2006: APC −1.7, 95% CI −2.1, −1.2; 2006–2017: APC −3.8, 95% CI −4.4, −3.1).ConclusionsOverall, there was a decrease in the incidence rate of localized prostate cancer after 2008, an increase in survival over time and a decrease in the mortality rate since the 1990s. This seems to indicate that the more conservative use of PSA screening tests in clinical practice since 2008 has not had a negative impact on population-wide prostate cancer outcomes.  相似文献   
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