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941.
Highly metastatic variants of mouse colon 38 colon carcinoma cells were established by repeated selection in vivo for liver metastasis and designated as SL4 cells. The SL4 cells formed colonies in the liver of 100% of syngenic mice when injected intrasplenically, while the incidence of liver metastasis was 27% of mice injected with parental cells. The weight of livers, which is an indicator of experimental hepatic metastasis formation, was significantly higher after intrasplenic injection and subsequent splenoctomy with SL4 cells than colon 38 cells. The incidence of hepatic metastasis after intracecal injection of SL4 cells was significantly higher than that of colon 38 cells. The SL4 cells were tested in vitro for their properties. Differences were not detected in the motility and invasive behavior between colon 38 cells and SL4 cells. SL4 cells showed a higher proliferation rate than colon 38 cells under adherent conditions. SL4 cells maintained a capacity to proliferate under non-adherent conditions whereas parental cells did not. SL4 cells should be a useful tool to study the mechanism of hepatic metastasis of colon carcinoma cells and to develop methods to prevent hepatic metastasis.  相似文献   
942.
Lymphocyte subpopulations (B cells, CD4, CD8), interleukin-20 receptors (IL-2), monocytes/macrophages (Leu M5), and HLA-DR antigen expression were studied immunohistochemically on frozen sections from 38 bladder cancer specimens. T cells predominated over B cells in all tumours. CD4-positive lymphocytes predominated over CD8 in the stroma (CD4/CD8: 1·35/1), while in epithelial tumour cells CD8 was the prominent subpopulation (CD8/CD4: 1·75/1). Aberrant HLA-DR expression was found in 21·05 per cent of bladder tumours. A strong correlation between CD4 and CD8 population densities and macrophages with the other subpopulations was noticed. In HLA-DR-positive tumours, there was no correlation of the percentage of positive cells with CD4- and CD8-positive lymphocyte populations. Various parameters including IL-2 receptors, B cells, CD8- and CD4-positive cells, and macrophages did not differ significantly between the groups of tumours expressing and not expressing HLA-DR antigen. There were no statistically significant differences in the population densities of B cells, CD8- or CD4-positive cells, IL-2 receptor, monocytes/macrophages, and HLA-DR antigen expression among various clinicopathological parameters, including growth pattern, histological grade and clinical stage or patient's age and sex. These findings suggest that in transitional cell carcinoma of the urinary bladder, HLA-DR antigen expression is independent of lymphocyte subpopulations. It is therefore possible that HLA-DR expression by tumour cells reflect the existence of separate HLA-DR-positive or HLA-DR-negative tumour clones.  相似文献   
943.
通过光镜和电镜对21例乳腺单纯癌和10例小叶增生病的观察,将其中9例单纯癌和7例小叶增生病的细胞连接变化,用Weibel氏形态定量法进行形态定量对比分析。结果表明:癌细胞的缝隙、桥粒、相嵌、并列和紧密等连接量的减少,与小叶增生病相比,两者差异有显著性。癌细胞连接量的减少与细胞分化程度有关。缝隙连接的减少,显示细胞恶变的开始;桥粒、相嵌和并列连接的减少,显示癌细胞分化程度的变化。减少程度愈高,分化程度愈低;恶性度愈高,侵袭性愈强。  相似文献   
944.
The expression of Fas antigen at the surface of renal cell carcinoma and the susceptibility to Fas-mediated lysis by a tumor specific CTL clone were investigated. Renal cell carcinoma cell lines expressed Fas antigen and were susceptible to apoptosis mediated by antibodies to Fas/APO1. Using RT-PCR, we further showed that these cell lines expressed mRNA for Fas deleted transmembrane region, corresponding to a soluble form of Fas/APO-1. To investigate the role of the Fas/FasL pathway in the cytotoxic response against RCC cells, we analyzed the induction of Fas-L on a tumor specific T cell clone (CTL 8C2), previously generated against one RCC cell line. Fas-L expression on CTL 8C2 was detected by RT-PCR after stimulation with autologous tumor cells. However, the cytotoxic activity of CTL 8C2 was completely abolished when EGTA was added, suggesting that the cytolysis was mainly mediated by a Ca++-dependent pathway, perforin/granzyme-based.  相似文献   
945.
Expression of syndecan-1, a cell surface proteoglycan that binds growth factors and extracellular matrix components, was studied in normal and pathological human uterine cervix using immunohistochemical methods. Normal cervical squamous epithelium showed positive staining for syndecan-1 in all cell layers, except the basal cell layer, whereas endocervical columnar epithelium stained weakly. In non-neoplastic reactive lesions, metaplastic squamous cells were positive for syndecan-1, whereas columnar cells showed weak or negative staining. In cervical condylomas, cells showing koilocytotic atypia were positive for syndecan-1. The progression of cervical intraepithelial neoplasia (CIN) grade I to grade III was associated with reduced syndecan-1 expression and localization of syndecan-1 to more superficial cell layers. In squamous cell carcinomas (SCCs), syndecan-1 expression correlated with histological differentiation, being absent from most poorly differentiated tumours. The results suggest that loss of syndecan-1 from atypical cells is an early event during cervical carcinogenesis and show a close association of syndecan-1 expression with preserved epithelial morphology and differentiation.  相似文献   
946.
ABSTRACT: Leukocyte adherence inhibition (LAI) assay was used to evaluate cell-mediated immunity in patients with invasive squamous cell carcinoma of the cervix. The reactivity of the peripheral blood leukocytes of these patients was evaluated after incubation with pooled extracts of allogeneic squamous cell carcinoma of the cervix. One hundred sixty-seven sets of LAI assays were performed on 54 individuals, including 23 patients with Stage I squamous cell carcinoma of the cervix, 9 patients with other stages of this tumor, 9 patients with unrelated tumors and 13 normal healthy volunteers. A protein concentration of one milligram per milliliter in the tumor extract and 10% fetal bovine serum in the feeding media gave the best results. Eighty-seven percent (28/32) of patients with squamous cell carcinoma of the cervix showed marked specific reactivity. No difference was found in the LAI indices of different stages of the disease.  相似文献   
947.
The clinicopathological features of central intraductal papillomas of the breast presenting with florid usual ductal hyperplasia or atypical ductal hyperplasia (ADH) were analyzed in a retrospective series of 119 patients, whose lesions were sent to the Armed Forces Institute of Pathology from 1976 to 1990. After histological review considering predefined morphological and quantitative criteria, the 119 central papillomas were classified into 22 papillomas with florid usual ductal hyperplasia (18%), 40 papillomas with focal atypia (34%), 24 atypical papillomas (20%) and 33 carcinomas arising in a papilloma (28%). After a median period of follow-up of 110 months, 16 recurrences (5 papillomas, 2 carcinomas arising in a papilloma, 4 ductal carcinomas in situ, 5 invasive carcinomas) occurred. No statistically significant difference was observed in relation to recurrence for the various categories of papillomas. The presence of epithelial hyperplasia, ADH or lobular neoplasia in the surrounding breast as well as infarction of the papilloma were significant predictive factors of recurrence (P=0.02 and P=0.005, respectively, log-rank test). The main reason for the observed low rate of significant recurrences in this series was that epithelial atypia (whether comprising 20% or 60% of the papillary lesion) was, in most of the cases, localized in a confined lesion that was completely excised.  相似文献   
948.
Sarcomatoid carcinoma is a rare variant of malignant tumor arising from the urinary tract. This tumor had been termed carcinosarcoma because of its carcinomatous and sarcomatous components. There is still some confusion in the terminology between true carcinosarcoma and sarcomatoid carcinoma; however, the latter is now regarded as primarily a malignant epithelial tumor with pseudosarcomatous transformation.
Four cases of sarcomatoid carcinoma arising from the urinary tract are reported. The patients were a 77 year old female, and three males aged 62, 69 and 80 years. All but the eldest patient complained of gross hematurla. Surgical removal was performed in the younger three cases, and an autopsy was done in the remaining case. All the tumors were macroscopically polypoid. Histopathologic examination revealed fasciculated spindle-cell tumors with myxold stroma or malignant fibrous histiocytoma-like spindle cell tumors. The epithelial nature was proven in these sarcomatous cells by immunohistochemical andlor electron-microscopic examinations. Only a small amount of squamous cell carcinoma components was also evident in the latter three cases. Although the younger three patients were alive at 44, 23 and 39 months'follow-up, respectively, constant careful monitoring Is recommended.  相似文献   
949.
The correlation of p53 protein overexpression and the K-ras codon 12 mutatlon wlth histologlc type, grade of cytologic atypla, depth of lnvasion and other histologlc prognostic factors was studied In paraffin sectlons from 43 ductectatic-and 70 solid-type pancreatic ductal carcinomas. Overexpression of p53 was found in 23.3% (10143) of ductectatic carcinomas (17.2% of intraductal and 35.7% of lnvaslve carclnomas) and in 61.4% (43/70) of solid carcinomas. In ductectatic cancers, p53 overexpression was detected In 14.8% (4/27) of carcinomas wlth lowgrade atypla (CAL), 50.0% (5110) of carcinomas wlth high-grade atypla (CAH) and in 16.7% (In) of mixed low- and hlgh-grade cancers. In the last group, expression was restricted to an area of CAH. In solld cancers, p53 overexpression did not dlffer by histologic type or grade. Overexpresslon of p53 and K-ras mutatlons did not correlate with histologlc prognostic factors (lymphatic, venous and perineural Invasion, and lymph node metastasls) in ductectatlc and solld cancers or depth of invasion of solld carclnomas. Our data suggest that p53 alteratlon occurs at an early intraductal stage of solld carcinoma, irrespectlve of cellular atypla, but Is low in ductectatic CAL and becomes hlgher In ductectatlc CAH. K-ras mutatlon, present In a high percentage of tumors of all groups and not correlating with the factors above, showed no changes In frequency with tumor progression.  相似文献   
950.
Cryostat sections from seventy-eight female breast carcinomas were assayed for oestrogen receptors by isoelectric focusing. Adjacent cryostat sections stained by Miller's elastic/van Gieson's method were graded for elastosis. Elastosis was similarly graded on near-equatorial paraffin sections from the same tumours. A positive correlation was obtained between elastosis in the near equatorial sections and oestrogen receptor positivity (p less than 0.0005), menstrual status (p less than 0.05) and parity (p less than 0.01) but no correlation was found between these factors and elastosis graded on cryostat sections from the more peripheral areas which had been selected for oestrogen receptor assay. These observations suggest that the central region of breast carcinomas, where connective tissue responses are fully developed, exhibits grades of elastosis with greater clinical significance. This may explain the conflicting published observations on the correlations between elastosis and oestrogen receptor status, which we believe are due to the lack of uniformity in tissue sampling. The possible implications of the absence of significant correlation between elastosis grades and tumour size, nodal status and disease-free interval are discussed.  相似文献   
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