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91.
目的探讨磷酰肌醇-3激酶途径在K562、NB4和HL60细胞增殖和凋亡抗性中的不同作用。方法短期培养法直接法G显带检测K562细胞和CML患者骨髓原代细胞的染色体核型,RQ-PCR检测K562细胞和CML患者骨髓原代细胞的bcr/abl基因;用磷酰肌醇-3激酶特异抑制剂渥曼青霉素(WT)抑制磷酰肌醇-3激酶活性,经细胞生长曲线测定、半固体集落形成实验、流式细胞膜联蛋白V标记技术检测细胞凋亡百分比和凋亡指数。观察K562、NB4和HL60细胞增殖能力及凋亡抗性的变化。统计学采用t检验。结果K562细胞G显带检出Ph染色体,RQ-PCR检测K562细胞存在bcr/abl基因;与标准Ph染色体表达的CML患者骨髓原代细胞的bcr/abl基因完全吻合;K562、NB4和HL60细胞在24h、48h、72h的增殖抑制率分别为41.33%、57.46%、65.85%和26.29%、5.51%、2.10%及32.14%、17.14%、13.14%。生长曲线显示WT抑制磷酰肌醇-3激酶途径可显著抑制K562细胞的增殖(P<0.05),而对NB4和HL60细胞增殖无明显影响(P>0.05)。K562、NB4和HL60细胞加和不... 相似文献
92.
Brian Cameron Allen M. Gown Hisham K. Tamimi 《American journal of obstetrics and gynecology》1994,170(6):1616-1622
OBJECTIVE: Much debate exists on the initiation of chemotherapy for women at risk for persistent gestational trophoblastic disease. This is a result of a lack of early predictors for the development of persistent gestational trophoblastic disease after evacuation of a complete hydatidiform mole, because the only current reliable method of detection and diagnosis lies in persistent or rising postmolar β-human chorionic gonadotropin values. We used immunocytochemical techniques to retrospectively study the expression of the c-erb B-2 oncogene product in formalin-fixed, paraffin-embedded trophoblastic tissues as a potential indicator of the development of persistent gestational trophoblastic disease. STUDY DESIGN: In this retrospective study 56 trophoblastic tumors were examined by means of immunocytochemical techniques to stain for the oncogene product for evidence of c-erb B-2 expression. Our 56 cases included original tissue from 20 cases of complete mole that progressed to persistent gestational trophoblastic disease, seven cases of choriocarcinoma after term pregnancy or abortion, and 29 cases of hydatidiform mole representing postevacuation, spontaneously regressing disease (including one partial mole). We also studied 11 cases of first-trimester trophoblast and 15 cases of term placenta as additional controls. RESULTS: Our results showed positive immunostaining for c-erb B-2 gene product in one case of persistent gestational trophoblastic disease, with negative staining in all other cases in the study groups and controls. CONCLUSION: Analysis for the significance of c-erb B-2 expression in persistent gestational trophoblastic disease showed that this correlation between c-erb B-2 expression and persistent gestational trophoblastic disease is not significant, suggesting that future efforts should be directed at the involvement of different oncoproteins. (AM J Obstet Gynecol 1994;170:1616-22.) 相似文献
93.
State of Adenomatous Polyposis Coli Gene and ras Oncogenes in Japanese Prostate Cancer 总被引:3,自引:1,他引:3
Hiroyoshi Suzuki Sara Aida Susumu Akimoto Tatsuo Igarashi Ryuichi Yatani Jun Shimazaki 《Cancer science》1994,85(8):847-852
Genetic alterations of ras oncogenes (K-, H- and N- ras ) and adenomatous polyposis coli (APC) gene in tissues of prostate cancer from Japanese patients were examined using PCR-SSCP (polymerase chain reaction-single strand conformation polymorphism) analysis and direct sequencing. Tissues from 8 cases of untreated stage B prostate cancer surgically removed and from 10 cases of endocrine therapy-resistant metastatic disease obtained at autopsy were used in the present study. In four out of 18 cases (22%), ras point mutations were found, two in either codon 12 or 61 of K-ras and two in either 13 or 61 of H- ras . These point mutations were detected in one of the stage B cases (13%) and in three of the autopsy cases (30%). All these cases were poorly differentiated adenocarcinoma. In autopsy cases showing ras mutation in cancerous prostate, the same alteration was observed in metastatic tissues. No APC gene mutation was detected in any sample, although polymorphism was found in some cases. These results indicate that ras oncogene mutations are related to the progression of prostate cancer, whereas APC gene alteration is not involved in tumorigenesis and development of this cancer. 相似文献
94.
Byron E. Butterworth Catherine S. Sprankle Susan M. Goldsworthy Daniel M. Wilson Thomas L. Goldsworthy 《Molecular carcinogenesis》1994,9(1):24-32
Furan administered by gavage for 2 yr has been reported to induce hepatocellular carcinomas in male and female B6C3F1 mice and in male but not female F344 rats. Chronic exposure studies in our laboratory using bioassay conditions showed extensive hepatocellular toxicity and sustained increases in regenerative cell proliferation after 1,3, and 6 wk of treatment in male and female rats and male mice. Altered expression of growth-control genes associated with this hyperproliferative state may enhance the susceptibility of these genes to mutation or may provide a selective growth advantage to preneoplastic cells. Quantitative northern blot analysis of mRNA was used to examine the expression of the oncogenes myc, fos, and Ha-ras in the livers of animals treated with furan. In male rats, a single administration of 30 mg/kg furan produced necrosis and a subsequent wave of cell proliferation 48 h after treatment and induced transient peaks in the expression of myc, fos, and Ha-ras 6–24 h after treatment. In male rat liver from our cell proliferation studies, only a slight increase in myc expression was seen at the end of week 1 of treatment. However, beginning at week 3 and increasing at week 6, up to a 15-fold increase over control values was observed in the expression of myc in the treated animals. The only other notable increase in expression observed in any animals from the cell proliferation study was a threefold increase in myc at week 6 in treated female rats. The absence of an increase in Ha-ras expression in the male mouse liver suggests that the unique patternof Ha-ras mutations previously reported in furan-induced mouse liver tumors is not due to increased mutational susceptibility related to overexpression of this gene. The lack of sustained expression of myc, fos, and Ha-ras in rapidly proliferating liver suggests that continuous expression of these genes is not necessary to maintain increased rates of cell replication. The large increase in myc expression in male but not female rats suggests an adaptive change that may be related to the sex-specific incidence of furan-induced hepatocellular carcinomas in rats. © 1994 Wiley-Liss, Inc. 相似文献
95.
96.
97.
表皮生长因子受体在大肠癌及癌前病变组织中的研究 总被引:4,自引:0,他引:4
用抗表皮生长因子受体(EGFR)的单抗和免疫组化ABC法,对正常大肠粘膜,大肠腺瘤伴异型增生及大肠腺癌进行标记,发现正常大肠粘膜全部为阴性,大肠腺瘤伴异型增生则有较高的表达率,而一旦癌变后,表达率有所下降,EGFR的表达与大肠腺癌的低分性及高浸相关,EGFR表达的肿瘤易发生淋巴结转移,研究结果提示,EGFR的表达与大肠癌的发生有一定关系,并可作为判断大肠癌生物学行为的一个有用指标。 相似文献
98.
Yasuni Nakanuma Kenichi Harada Akira Ishikawa Yoh Zen Motoko Sasaki 《Journal of hepato-biliary-pancreatic sciences》2003,10(4):265-281
Intrahepatic cholangiocarcinoma (ICC) is the second most common malignant tumor of the liver, and ICC is reportedly increasing recently. ICC is usually adenocarcinoma with variable desmoplastic reaction, although there are several special or unusual histological features. ICC may arise at the large intrahepatic bile duct near the hepatic hilus and also from the bile ductules at the border of the hepatic parenchyma. On the anatomical level, the pathology of ICC differs depending on the region from which the ICC arises. At the large intrahepatic bile duct, ICC presents papillary growth and periductal infiltration. Some cases show extensive papillary growth and intraluminal spread with marked gastroenteric metaplasia. Mucus core protein 1 is expressed in aggressive ICC. ICC arising from ductules shares phenotypes of hepatocellular carcinoma. ICC in chronic biliary diseases, particularly arising in hepatolithiasis, presents precancerous lesions that include biliary epithelial dysplasia, as well as in-situ carcinoma. Chronic advanced hepatitis C is one of the background diseases of ICC. Chronic inflammation, with the upregulation of cyclooxygenase-2 and growth factors, and the formation of reactive oxygen species are one of the causative factors in the DNA damage of biliary epithelial cells. K-ras mutation and aberrant expression of p53 are found in one-third of ICCs. The latter may be due to mdm-2 upregulation. Hepatocyte growth factor/met and interleukin 6 (IL6)/IL6 receptor are involved in cell proliferation/mitoinhibition and apoptosis in ICC. Fibrous stroma formation and invasion involve the proliferation of Α-smooth muscle antigen-positive stromal cells, and cell-to-cell and cell-to-matrix interactions involving E-cadherin/catenin and CD44 and matrix proteinases may be involved in the invasion of ICC. Evasion of immune surveillance involving the Fas/FasL system is important in the malignant progression of ICC. Further molecular and genetic studies are mandatory to evaluate the pathogenesis and progression of ICC. 相似文献
99.
Expression of c-erbB2 in gestational trophoblastic disease and its clinical significance 总被引:1,自引:0,他引:1
Summary: In order to explore a potential indicator of predicting the occurrence and development of gestational trophoblastic tumor, the expression of c-erbB2 oncogene in human normal placenta, hyda tidiform mole and choriocarcinoma was investigated. The expression of c-erbB2 was detected im munohistochemically by monoclonal antibody against the gene on the formalin-fixed paraffin sections of 21 hydatidiform moles, 21 invasive moles, 20 choriocarcinomas and 30 normal placentas. Results showed that the expression level of c-erbB2 was significantly higher in gestational trophoblastic tumor than in hydatidiform mole and normal placenta of midterm and term pregnancy (P<0. 05), while there was no significant difference between patients with gestational trophoblastic tumor of stage Ⅲ ,Ⅳ and those of stage Ⅰ , Ⅱ . It was demonstrated that overexpression of c-erbB2 may closely associ ated with malignant transformation of hydatidiform mole, not only providing important insight into pathogenesis of gestational trophoblastic tumor, but also having an important significance for the ear-ly diagnosis and early treatment of gestational trophoblastic tumor. 相似文献
100.