组织蛋白酶B在甲状腺肿瘤组织中的表达及其意义

目的探讨组织蛋白酶B(CathepsinB,CTSB)在甲状腺肿瘤组织中的表达及其与甲状腺肿瘤发生发展的相关性。方法采用荧光原底物法检测甲状腺癌、甲状腺腺瘤及正常甲状腺各30份组织标本中CTSB的活性,采用Western blot法检测各组织中CTSB蛋白的表达。结果甲状腺癌和甲状腺腺瘤组织中CTSB的活性及蛋白表达水平均显著高于正常甲状腺组织(P<0.05),而甲状腺癌组织中二者均显著高于甲状腺腺瘤组织(P<0.05)。结论 CTSB的表达与甲状腺肿瘤的发生发展密切相关。     

1-整合蛋白在甲状腺肿瘤及其正常甲状腺组织中的表达

目的 研究1-整合蛋白在甲状腺肿瘤及其正常甲状腺组织中的表达情况.方法 采用S-P免疫组化检测方法,对甲状腺34例乳头状腺癌.19例滤泡腺瘤.6例滤泡腺癌.2例髓样癌和10例结节状增生进行1-整合蛋白检测.结果 79.4%(27/34)的甲状腺乳头状癌组织表现为1-整合蛋白在癌细胞中过度表达,而滤泡状腺瘤和腺癌,髓样癌和结节状增生组织中则表现为1-整合蛋白阴性.在伴有淋巴结转移的乳头状腺癌中,5例表现为原发灶与继发灶1-整合蛋白表达分布特点的明显不同,而3例表现为原发灶阳性,但继发灶却阴性.在伴有淋巴结转移的原发灶中1-整合蛋白阳性率达91.7%,而在无转移的原发灶中阳性率为72.7%.结论 1-整合蛋白的免疲组化检测有助于甲状腺乳头状癌的诊断,但与淋巴结转移无关.而且,1-整合蛋白在淋巴结转移灶的表达特点明显与原发灶不同.     

化学反应摩尔焓变的测定及Origin在数据处理中的应用

针对目前化学反应摩尔焓变实验教学中存在的问题,对量热计的加料装置进行了改进,并用同电脑可连接的温度测量仪测量、记录体系温度变化,并将实验数据导入Origin制图,减少了人为的误差,提高了实验的精确度,结果表明:实验相对误差小于0.5%。     

新型防砂技术在辽河油田套变井中的研究及应用

针对套变井防砂难题,在总结原有防砂技术的基础上,研究开发出该新型防砂工艺技术。该技术创造性的提出采用机械充填防砂技术解决套管变形井出砂难题,恢复套管变形井产能,并成功应用到现场,解决了一大批油井因套管变形及油层出砂而无法正常生产的难题。该技术为套管变形井、特别是油层部位套管变形井的治理、提高油层动用程度提出了一条可行的解决方案。     

Glut-1、VEGF在胰腺癌中的表达及意义

目的研究葡萄糖转运蛋白-1(Glut-1)及血管内皮生长因子(VEGF)在胰腺癌中的表达及意义。方法应用半定量RT-PCR及免疫组织化学染色技术检测Glut-1、VEGF在胰腺癌及正常胰腺组织中的表达。结果RT-PCR结果显示Glut-1mRNA、VEGFmRNA在正常胰腺和胰腺癌组织中均有表达,但在胰腺癌组织中的表达量明显高于正常胰腺组织(P<0.01);免疫组化染色阳性细胞计数显示Glut-1、VEGF在胰腺癌组织中的阳性细胞数明显多于正常胰腺组织(P<0.01)。结论Glut-1与VEGF的异常表达可能在胰腺癌的发生中起协同作用;VEGF通过上调Glut-1表达促进胰腺癌的发生发展。     

全低变技术在年产5万t合成氨节能装置中的特征及效益

该文对全低变工艺的特征进行了论述 ,并针对存在的问题提出了改进措施     

有机酸及相关盐类在果蔬护色、防褐变中的应用研究

考察了不同浓度的曲酸、抗坏血酸、乳酸及ZnC l2、CaC l2、乳酸锌、乳酸钙处理苹果和梨的防褐变时间。结果表明,曲酸的护色效果最好。当曲酸浓度>0.1%时,防褐变效果很好,24 h时只有轻微褐变;当乳酸钙浓度>1.0%,抗坏血酸浓度>0.25%,ZnC l2浓度>0.75%,CaC l2浓度>1.0%时,防褐变效果均较好。     

抗肿瘤坏死因子-α单链抗体在大肠杆菌中的表达及表达条件的优化

目的构建抗肿瘤坏死因子-α(Tumor necrosis factor-α,TNF-α)单链抗体(Single chain fragment variable,scFv)的原核高效表达体系,并优化表达条件。方法在引物中添加编码6×His的核苷酸片段,使目的蛋白C-末端带有6×His标签。从质粒pCANTAB 5E-scFv中PCR扩增scFv基因,连接至pBV220载体,连接产物分别转化至E.coli BL21(DE3)和DH5α中,42℃诱导表达,并对诱导时间、培养基pH值和类型进行优化,Western blot分析表达产物的反应原性。结果 PCR扩增出的scFv基因片段长度约770 bp,且序列正确;重组表达质粒pBV220-scFv经酶切鉴定证明构建正确;在E.coli BL21(DE3)中可获得表达,在E.coli DH5α中不表达;表达的重组scFv相对分子质量约为28 000,以包涵体形式存在于胞浆中,表达量约占菌体总蛋白的15%,且可与抗His-Tag抗体发生特异性反应;工程菌的最佳诱导表达条件为:以E.coli BL21(DE3)为宿主菌,在pH 7.4的LB培养基中,42℃诱导5 h。结论将scFv的表达载体更换为pBV220,可提高scFv的表达量,在优化表达条件下,scFv的表达水平进一步提高。     

基于TCGA数据库和蛋白-蛋白对接分析DMGDH在肾透明细胞癌组织中的表达及临床意义

目的:本研究旨在明确二甲基甘氨酸脱氢酶(DMGDH)基因在泛癌中的表达情况及与患者预后的相关性,并探讨DMGDH在肾透明细胞癌(KIRC)中的相关功能及可能机制.方法:利用癌症基因组图谱(TCGA)数据分析DMGDH在泛癌中的表达差异情况,并通过Cox回归法分析DMGDH与各种肿瘤临床预后的相关性.根据DMGDH的表达...     

S100A4蛋白在甲状腺乳头状癌中的表达及意义

目的探讨甲状腺乳头状癌中S100A4蛋白的表达,分析其与甲状腺乳头状癌发生及淋巴结转移的关系。方法应用免疫组织化学SP法检测50例甲状腺乳头状癌组织、14例甲状腺腺瘤组织、26例结节性甲状腺肿组织和10例正常甲状腺组织中S100A4蛋白的表达。结果甲状腺乳头状癌中S100A4蛋白的阳性表达率为78.00%,明显高于甲状腺腺瘤组织、结节性甲状腺肿组织及正常甲状腺组织(P<0.05);S100A4蛋白在癌组织中的表达与甲状腺乳头状癌淋巴结转移有关(P<0.05)。结论 S100A4蛋白的高表达与甲状腺乳头状癌的发生发展和淋巴结转移密切相关,其检测有助于鉴别甲状腺良恶性病变,并预测肿瘤的发展和预后。     

MicroRNA Expression in Clear Cell Renal Cell Carcinoma Cell Lines and Tumor Biopsies: Potential Therapeutic Targets

This study was carried out to quantitate the expression levels of microRNA-17, -19a, -34a, -155, and -210 (miRs) expressed in nine clear cell renal cell carcinoma (ccRCC) and one chromophobe renal cell carcinoma cell line with and without sarcomatoid differentiation, and in six primary kidney tumors with matching normal kidney tissues. The data in the five non-sarcomatoid ccRCC cell lines—RC2, CAKI-1, 786-0, RCC4, and RCC4/VHL—and in the four ccRCC with sarcomatoid differentiation—RCJ41T1, RCJ41T2, RCJ41M, and UOK-127—indicated that miR-17 and -19a were expressed at lower levels relative to miR-34a, -155, and -210. Compared with RPTEC normal epithelial cells, miR-34a, miR-155, and miR-210 were expressed at higher levels, independent of the sarcomatoid differentiation status and hypoxia-inducible factors 1α and 2α (HIFs) isoform expression. In the one chromophobe renal cell carcinoma cell line, namely, UOK-276 with sarcomatoid differentiation, and expressing tumor suppressor gene TP53, miR-34a, which is a tumor suppressor gene, was expressed at higher levels than miR-210, -155, -17, and -19a. The pilot results generated in six tumor biopsies with matching normal kidney tissues indicated that while the expression of miR-17 and -19a were similar to the normal tissue expression profile, miR-210, -155, -and 34a were expressed at a higher level. To confirm that differences in the expression levels of the five miRs in the six tumor biopsies were statistically significant, the acquisition of a larger sample size is required. Data previously generated in ccRCC cell lines demonstrating that miR-210, miR-155, and HIFs are druggable targets using a defined dose and schedule of selenium-containing molecules support the concept that simultaneous and concurrent downregulation of miR-210, miR-155, and HIFs, which regulate target genes associated with increased tumor angiogenesis and drug resistance, may offer the potential for the development of a novel mechanism-based strategy for the treatment of patients with advanced ccRCC.     

Accumulation of Uroporphyrin I in Necrotic Tissues of Squamous Cell Carcinoma after Administration of 5-Aminolevulinic Acid

5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PpIX) fluorescence is widely used for the intraoperative detection of malignant tumors. However, the fluorescence emission profiles of the accompanying necrotic regions of these tumors have yet to be determined. To address this, we performed fluorescence and high-performance liquid chromatography (HPLC) analyses of necrotic tissues of squamous cancer after 5-ALA administration. In resected human lymph nodes of metastatic squamous cell carcinoma, we found a fluorescence peak at approximately 620 nm in necrotic lesions, which was distinct from the PpIX fluorescence peak at 635 nm for viable cancer lesions. Necrotic lesions obtained from a subcutaneous xenograft model of human B88 oral squamous cancer also emitted the characteristic fluorescence peak at 620 nm after light irradiation: the fluorescence intensity ratio (620 nm/635 nm) increased with the energy of the irradiation light. HPLC analysis revealed a high content ratio of uroporphyrin I (UPI)/total porphyrins in the necrotic cores of murine tumors, indicating that UPI is responsible for the 620 nm peak. UPI accumulation in necrotic tissues after 5-ALA administration was possibly due to the failure of the heme biosynthetic pathway. Taken together, fluorescence imaging of UPI after 5-ALA administration may be applicable for the evaluation of tumor necrosis.     

Effect of EGFR on SQSTM1 Expression in Malignancy and Tumor Progression of Oral Squamous Cell Carcinoma

Oral squamous cell carcinoma (OSCC) is one of the most common types of malignant tumor. Sequestosome 1 (SQSTM1) serves as an adaptor of autophagy for degrading protein aggregates. The regulation of autophagy by EGFR and its clinical impacts are indicated in various types of cancer. However, the association of EGFR and SQSTM1 in OSCC is still unknown. Our results show that the expression levels of SQSTM1 and EGFR proteins are higher in tumor tissues than in the corresponding tumor-adjacent (CTAN) tissues of OSCC patients. The expression levels of SQSTM1 were positively associated with the EGFR expression level. High co-expression of SQSTM1 and EGFR is associated with poor prognosis in OSCC patients. Moreover, SQSTM1 expression is decreased in EGFR-knockdown cells. Cell growth and invasion/migration are also decreased in cells with single/combined knockdowns of EGFR and SQSTM1 or in SQSTM1-knockdown cells without EGFR kinase inhibitor Lapatinib treatment compared to that in scrambled cells. However, cell growth and invasion/metastasis were not significantly different between the scrambled cells and SQSTM1-knockdown cells in the presence of Lapatinib. This study is the first to indicate the biological roles and clinical significance of SQSTM1 regulation by EGFR in OSCC.     

Spreading of Isolated Ptch Mutant Basal Cell Carcinoma Precursors Is Physiologically Suppressed and Counteracts Tumor Formation in Mice

Basal cell carcinoma (BCC) originate from Hedgehog/Patched signaling-activated epidermal stem cells. However, the chemically induced tumorigenesis of mice with a CD4Cre-mediated biallelic loss of the Hedgehog signaling repressor Patched also induces BCC formation. Here, we identified the cellular origin of CD4Cre-targeted BCC progenitors as rare Keratin 5⁺ epidermal cells and show that wildtype Patched offspring of these cells spread over the hair follicle/skin complex with increasing mouse age. Intriguingly, Patched mutant counterparts are undetectable in age-matched untreated skin but are getting traceable upon applying the chemical tumorigenesis protocol. Together, our data show that biallelic Patched depletion in rare Keratin 5⁺ epidermal cells is not sufficient to drive BCC development, because the spread of these cells is physiologically suppressed. However, bypassing the repression of Patched mutant cells, e.g., by exogenous stimuli, leads to an accumulation of BCC precursor cells and, finally, to tumor development.     

Frequent Epigenetic Suppression of Tumor Suppressor Gene Glutathione Peroxidase 3 by Promoter Hypermethylation and Its Clinical Implication in Clear Cell Renal Cell Carcinoma

The goal of this study is to identify novel tumor suppressor genes silenced by promoter methylation in clear cell renal cell carcinoma (ccRCC) and discover new epigenetic biomarkers for early cancer detection. Reactive oxygen species (ROS) is a major cause of DNA damage that correlates with cancer initiation and progression. Glutathione peroxidase 3 (GPX3), the only known extracellular glycosylated enzyme of GPXs, is a major scavenger of ROS. GPX3 has been identified as a tumor suppressor in many cancers. However, the role of GPX3 in ccRCC remains unclear. This study aimed to investigate its epigenetic alteration in ccRCC and possible clinicopathological association. In our study, GPX3 methylation and down-regulation were detected in 5 out of 6 ccRCC cell lines and the GPX3 mRNA and protein expression level in ccRCC tumors was significantly lower than in adjacent non-malignant renal tissues (p < 0.0001). Treatment with 5-Aza-2''-deoxycytidine restored GPX3 expression in ccRCC cells. Aberrant methylation was further detected in 77.1% (162/210) of RCC primary tumors, but only 14.6% (7/48) in adjacent non-malignant renal tissues. GPX3 methylation status was significantly associated with higher tumor nuclear grade (p = 0.014). Thus, our results showing frequent GPX3 inactivation by promoter hypermethylation in ccRCC may reveal the failure in the cellular antioxidant system in ccRCC and may be associated with renal tumorigenesis. GPX3 tumor specific methylation may serve as a biomarker for early detection and prognosis prediction of ccRCC.     

BAK和BAG-1蛋白在结直肠癌中的表达及其意义

目的探讨BAK和BAG-1蛋白在结直肠癌中的表达及其意义。方法采用免疫组化SP法对80例结直肠癌、40例结直肠腺瘤及25例癌旁正常结直肠黏膜组织中BAK和BAG-1蛋白的表达进行检测,并分析其与结直肠癌临床病理特征之间的相关性。结果 BAK和BAG-1蛋白在结直肠癌中过度表达,表达率分别为72.5%(58/80)和80%(64/80),且BAG-1蛋白与肿瘤的分化程度呈负相关,BAK蛋白与肿瘤的分化程度呈正相关。有淋巴结转移的结直肠癌,其BAG-1蛋白的表达率为96.7%(29/30),无淋巴结转移的结直肠癌,其BAG-1蛋白的表达率为70%(35/50),两者相比差异有统计学意义(P<0.01)。结论 BAK和BAG-1蛋白的过度表达与肿瘤的分化程度密切相关,且BAG-1蛋白的过度表达还与肿瘤的淋巴结转移密切相关;结直肠癌的发生机制可能涉及BAK和BAG-1调节环路中多个基因的异常。     

肺癌抑癌基因1对鼻咽癌细胞株HNE-1增殖与侵袭能力的影响

目的探讨肺癌抑癌基因1(Tumor suppressor in lung cancer 1,TSLC1)对鼻咽癌细胞株HNE-1增殖与侵袭能力的影响。方法采用RT-PCR法从乳腺癌细胞株MCF-7中扩增TSLC1基因全长编码区序列,构建重组真核表达质粒pcDNA3.1-TSLC1,转染HNE-1细胞,RT-PCR及Western blot检测TSLC1基因mRNA和蛋白的表达水平。MTT和Transwell小室试验检测TSLC1基因过表达对HNE-1细胞增殖及侵袭能力的影响。结果重组表达质粒pcDNA3.1-TSLC1经双酶切及测序证明构建正确;稳定转染重组表达质粒的HNE-1细胞中TSLC1基因出现过表达;TSLC1基因过表达可显著抑制HNE-1细胞的增殖与侵袭能力。结论 TSLC1基因过表达对HNE-1细胞增殖与侵袭能力具有明显的抑制作用,为鼻咽癌的基因治疗提供了理想的分子靶点。