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41.
目前临床上有许多怀疑前列腺癌但穿刺阴性的病例,为了避免漏诊,多数患者必须接受重复穿刺。尽管部分患者经重复穿刺确诊为前列腺癌,而更多患者经过长期随访以及反复穿刺最终确诊为良性病变。近期研究证实,癌灶附近的组织学表现正常的组织中也可发生与癌灶相似的分子改变。因此,我们认为在前列腺癌的发生过程中存在区域效应。在这一理论指导下,选择适当的可反映前列腺癌区域效应的标记物,在穿刺阴性的标本中检出与癌灶相似的分子改变,就可以帮助临床医生在常规病理诊断之前,提前预测前列腺癌的发生。如果能够找到这样的标记物,并在大规模的诊断试验中证实其可行性,那么就可以极大地改善前列腺癌诊断的现状。  相似文献   
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Nitric oxide (NO) participates in neuronal lesions in the digestive form of Chagasdisease and the proximity of parasitised glial cells and neurons in damaged myentericganglia is a frequent finding. Glial cells have crucial roles in manyneuropathological situations and are potential sources of NO. Here, we investigateperipheral glial cell response to Trypanosoma cruzi infection toclarify the role of these cells in the neuronal lesion pathogenesis of Chagasdisease. We used primary glial cell cultures from superior cervical ganglion toinvestigate cell activation and NO production after T. cruziinfection or lipopolysaccharide (LPS) exposure in comparison to peritonealmacrophages. T. cruzi infection was greater in glial cells, despitesimilar levels of NO production in both cell types. Glial cells responded similarlyto T. cruzi and LPS, but were less responsive to LPS thanmacrophages were. Our observations contribute to the understanding of Chagas diseasepathogenesis, as based on the high susceptibility of autonomic glial cells toT. cruzi infection with subsequent NO production. Moreover, our findingswill facilitate future research into the immune responses and activation mechanismsof peripheral glial cells, which are important for understanding the paradoxicalresponses of this cell type in neuronal lesions and neuroprotection.  相似文献   
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Synthesis and biological evaluation of a series of 6-aminopyrazolyl-pyridine-3-carbonitriles as JAK2 kinase inhibitors was reported. Biochemical screening, followed by profile optimization, resulted in JAK2 inhibitors exhibiting good kinase selectivity, pharmacokinetic properties, physical properties and pharmacodynamic effects.  相似文献   
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Cervical cancer development following a persistent infection with high-risk human papillomavirus (hrHPV) is driven by additional host-cell changes, such as altered DNA methylation. In previous studies, we have identified 12 methylated host genes associated with cervical cancer and pre-cancer (CIN2/3). This study systematically analyzed the onset and DNA methylation pattern of these genes during hrHPV-induced carcinogenesis using a longitudinal in vitro model of hrHPV-transformed cell lines (n = 14) and hrHPV-positive cervical scrapings (n = 113) covering various stages of cervical carcinogenesis. DNA methylation analysis was performed by quantitative methylation-specific PCR (qMSP) and relative qMSP values were used to analyze the data. The majority of genes displayed a comparable DNA methylation pattern in both cell lines and clinical specimens. DNA methylation onset occurred at early or late immortal passage, and DNA methylation levels gradually increased towards tumorigenic cells. Subsequently, we defined a so-called cancer-like methylation-high pattern based on the DNA methylation levels observed in cervical scrapings from women with cervical cancer. This cancer-like methylation-high pattern was observed in 72% (38/53) of CIN3 and 55% (11/20) of CIN2, whereas it was virtually absent in hrHPV-positive controls (1/26). In conclusion, hrHPV-induced carcinogenesis is characterized by early onset of DNA methylation, typically occurring at the pre-tumorigenic stage and with highest DNA methylation levels at the cancer stage. Host-cell DNA methylation patterns in cervical scrapings from women with CIN2 and CIN3 are heterogeneous, with a subset displaying a cancer-like methylation-high pattern, suggestive for a higher cancer risk.  相似文献   
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HPV16型E7复制型DNA疫苗诱发的抗肿瘤免疫反应   总被引:5,自引:0,他引:5  
为了研制有效的疫苗 ,用于HPV16型重度感染和与其感染相关的宫颈癌晚期病人手术后的免疫治疗 ,用复制型DAN疫苗载体 pSCA1,在其CMVIE启动子之下插入修饰的HPV16型E7基因mE7- 3( 2 4G、2 6G、6 7R) ,构建成 pSCA1mE7- 3复制型DNA疫苗。以重组质粒免疫C5 7BL/ 6小鼠 ,检测诱发的特异性CTL活性 ;将免疫后的小鼠用TC - 1肿瘤细胞攻击 ,观察免疫保护效果。实验结果显示 :pSCA1mE7- 3复制型DNA疫苗能诱导小鼠产生针对TC - 1肿瘤细胞的特异性CTL反应 ;复制型DNA疫苗免疫后的小鼠能耐受 1× 10 4 TC - 1细胞的攻击 ,成瘤时间推迟 ,并且成瘤率明显下降 ,部分小鼠得到保护能免受肿瘤攻击。因此pSCA1mE7- 3复制型DNA疫苗可作为HPV16相关肿瘤的癌前病变及中晚期病人术后免疫治疗的候选疫苗。  相似文献   
49.
NAG11和NAG12基因转染对鼻咽癌细胞生长的影响   总被引:1,自引:0,他引:1  
为了考察鼻咽癌表达下调/缺失基因NAG11和NAG12对鼻咽癌细胞系HNE1生长的影响,构建了NAG11和NAG12基因真核表达载体pcDNA3.1(+)/NAG11和pcDNA3.1(+)/NAG12,采用脂质体转染技术将真核重组质粒和空载体质粒分别导入HNE1细胞,观察转染后HNE1细胞生物学特性的变化,结果显示,NAG11重表达对HNE1细胞生长和细胞周期没有明显的影响,而NAG12重表达对HNE1细胞有生长抑制作用,与空载体转染组相比,倍增时间由24.1h延长至31.1h,停滞于G0-G1期细胞数由51.42%增加至68.14%。以上实验进一步说明鼻咽癌是多基因改变的疾病,NAG12的重表达有助于处国咽癌恶性表型的逆转。  相似文献   
50.
BackgroundRecent studies have reported that diffuse large B-cell lymphoma (DLBCL) involving different primary extranodal sites have distinct clinicopathological characteristics and prognosis. However, the risk of secondary malignant neoplasms (SMNs) in DLBCL survivors with different primary extranodal sites are unknown.MethodsA total of 40,714 patients diagnosed with stage I/II DLBCL were included from the Surveillance, Epidemiology, and End Results (SEER) database from 1983 to 2015.The standardized incidence ratio (SIR) and absolute excess risk (AER) were used to assess the risk of SMNs.ResultsThe results show that the risk of SMN was significantly higher in extranodal DLBCL than in the US general population (SIR, 1.18; 95% CI, 1.11–1.26), and the risk of developing SMN remains significantly elevated with increased latency. Moreover, there were multiple site-specific risk patterns. There was a 22%, 44%, 66%, 123% and 151% increased risk of SMN 10 years after primary gastrointestinal tract, head/neck, skeletal, lung and liver/pancreas DLBCL diagnosis, respectively. There was a significant decrease risk of SMN with increasing age at diagnosis for primary gastrointestinal tract and skeletal DLBCL. In addition, DLBCL patients with primary sites in the gastrointestinal tract, thyroid and liver/pancreas had the highest incidences of secondary stomach cancer, second thyroid cancer, and second hepatobiliary cancer, respectively, which indicated that the initial site of DLBCL may predict the type of SMN.ConclusionsThe strategies for cancer surveillance after extranodal DLBCL diagnosis may need to be individualized according to the subsite of extranodal DLBCL.  相似文献   
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