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1.
L Ossowski 《Cell》1988,52(3):321-328
We have previously shown that inhibition of uPA activity of a human tumor-HEp3-results in a drastic reduction of its metastasis in the chick embryo. Using 125IUdR-labeled tumor cells, we have now studied the role of uPA in individual steps of tumor metastasis. We found that, 48 hr after inoculation of tumor cells on the CAM, the organs of the embryos, inoculated with cells in which uPA was inhibited, contained 4-fold less cells than the controls. Neither the initial advance of the tumor mass into the CAM nor the process of extravasation was affected by the inhibition of tumor uPA. However, the infiltration of the CAM mesenchyme by individual tumor cells was blocked when tumor uPA activity or production was inhibited. In addition, indirect evidence implicated uPA as an essential factor in the tumor cell intravasation.  相似文献   

2.
Summary The mouse mammary fatpad is immunologically privileged relative to the subcutis for the transplantation of nonmalignant tissues. Mouse mammary tumors, however, induce tumor-specific immunity in the mammary fatpad. Immunizing tumor cells were injected into the fatpad or subcutis at several time periods before challenge tumor cells were injected into the subcutis on the contralateral side and the time of onset of concomitant immunity was determined. Mice immunized by transplantion of tumor cells into the subcutis became resistant to challenge tumor transplants before mice immunized with tumor cells transplanted into the fatpad. By utilizing a metastatic tumor line which is resistant to thioguanine and ouabain, it was directly demonstrated that tumor cells from a s.c. implant reached the regional inguinal lymph node before tumor cells from a mammary fatpad tumor implant.  相似文献   

3.
Bladder cancer is one of the most common tumors of the genitourinary tract. Here, we use phage display to identify a peptide that targets bladder tumor cells. A phage library containing random peptides was screened for binding to cells from human bladder tumor xenografts. Phage clones were further selected for binding to a bladder tumor cell line in culture. Six clones displaying the consensus sequence CXNXDXR(X)/(R)C showed selective binding to cells from primary human bladder cancer tissue. Of these, the CSNRDARRC sequence was selected for further study as a synthetic peptide. Fluorescein-conjugated CSNRDARRC peptide selectively bound to frozen sections of human bladder tumor tissue, whereas only negligible binding to normal bladder tissue was observed. When the fluorescent peptide was introduced into the bladder lumen, in a carcinogen-induced rat tumor model, it selectively bound to tumor epithelium. Moreover, when the peptide was intravenously injected into the tail vein, it homed to the bladder tumor but was not detectable in normal bladder and control organs. Next, we examined whether the peptide can detect tumor cells in urine. The fluorescent peptide bound to cultured bladder tumor cells but not to other types of tumor cell lines. Moreover, it bound to urinary cells of patients with bladder cancer, while showing little binding to urinary cells of patients with inflammation or healthy individuals. The CSNRDARRC peptide may be useful as a targeting moiety for selective delivery of therapeutics and as a diagnostic probe for the detection of bladder cancer.  相似文献   

4.
Summary Lactate dehydrogenase (LDH) and LDH isoenzyme activities were determined in tumor tissue, tumor cystic fluid, and serum from athymic mice with transplants of a human testicular germ cell tumor. High activity of LDH-1 was found in tumor tissue and tumor cystic fluid. By histochemical staining LDH was found in all tumor cells. Most tumor cells had a faint staining reaction while some cells dispersed throughout the tumor had a strong staining reaction. The serum LDH-1 in athymic mice with tumor transplants correlated markedly with the tumor volume. The results indicate that serum LDH-1 was derived from the testicular germ cell tumor transplants.  相似文献   

5.
The mechanisms of tumor rejection by cell-mediated immunity were reviewed in a rat autochthonous and syngeneic tumor-host system. The immune system could mediate a complete regression of autochthonous tumor if the tumor cells were immunogenic. Neutrophils and macrophages first appeared following transplantation of autochthonous tumor. Lymphocytes increased in the tumor tissue as the tumor began to show regression. Degenerated tumor tissue was infiltrated by macrophages and plasma cells. The identification of rat hematopoietic cells including various subsets of lymphocytes and inflammatory cells became possible owing to a variety of monoclonal antibodies reacting with these cells. Major populations of tumor-infiltrating lymphocytes (TIL) were found to be R1-3B3 (CD5)- and R1-10B5 (CD8)-positive cells in methylcholanthrene-induced autochthonous tumor. These CD5- and CD8-positive lymphocytes were also recognized in an N-nitrosourea-induced syngeneic tumor-host system and actually showed specific cytotoxicity against tumor cells in vitro. Macrophages were recognized in tumor tissues more predominantly in the early and terminal phase of tumor rejection; their functions are still uncertain but they are considered to have important immunomodulatory effects. A variety of cytokines were thought to play an important role in augmenting host immunity to achieve tumor rejection. Neutrophils in the tumor tissue were shown to produce a factor attracting lymphocytes to the tumor site, which was designated as lymphocyte migration factor. Subsequently, activities of colony-stimulating factor, interleukin-1, -2, and -3, and cytotoxic-T-cell-generating factor (CGF), which induces final maturation of cytotoxic T cells, were detected at the tumor site as well as in the regional lymph nodes and the spleen. CGF was found to be produced by W3/25 (CD4)-positive T cells. Lymphocytes residing in the spleen of the immune rats did not show cytotoxic activity against tumor cells but significant tumor lysis activity was recognized with TIL. This suggests that lymphocytes may achieve maturation after they leave the spleen. Cellular reactions occurring at the tumor site were enhanced at each step by various cytokines produced by lymphocytes as well as by inflammatory cells. This cytokine cascade seems to be essential for obtaining a sufficient immune response for tumor rejection. When an established T9 subcutaneous tumor with a diameter of 10 mm was treated by intratumoral infusion of lymphokine-activated killer (LAK) cells, the tumor showed complete regression after 2-3 weeks of transient growing.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

6.
7.
Tryptophan degradation in transplanted tumor cells undergoing rejection   总被引:6,自引:0,他引:6  
The depletion of an essential amino acid, tryptophan, caused by indoleamine 2,3-dioxygenase induction in vitro, has been shown to be due to a mechanism that is used in self-defense against inhaled microorganisms and tumor growth. In this communication, we report the results of measuring dioxygenase activity in the peritoneal exudate cells and tumor cytotoxicity at the transplantation loci after in vivo transplantation of tumor cells into the peritoneal cavity of syngeneic or allogeneic strains of mice. The enzyme was induced only when the tumor cells were being rejected from allogeneic animals and no change was observed when the cells continued to grow in syngeneic animals. Furthermore, when the syngeneic tumor cells in a diffusion chamber were i.p. transplanted simultaneously with i.p. injection of allogeneic tumor cells, the enzyme was induced not only in allografted tumor cells but also in the syngeneic tumor cells. Under these conditions, the tumor cells in the diffusion chamber ceased to grow and 50% of the cells were rejected. To determine the type of cells containing the induced enzyme, the peritoneal exudate cells (tumor cells and host cells--mostly small lymphocytes) were separated into six fractions by sedimentation under gravity and by differential centrifugation. Approximately 80% of total enzyme activity was localized in a tumor-rich fraction (98.9% purity), whereas only 0.2% of the activity was found in a lymphocyte-rich fraction (99.5% purity). The localization of indoleamine 2,3-dioxygenase in the tumor cells was confirmed by complement-dependent lysis with specific antibodies against tumor and host cells.  相似文献   

8.
The relationship between hematologic status and severity of tumor affliction in green turtles (Chelonia mydas) with fibropapillomatosis (FP) was examined. During 1 wk periods in July 1997 and July 1998, we bled 108 free-ranging green turtles from Pala'au (Molokai, Hawaii, USA) where FP is endemic. Blood was analyzed for hematocrit, estimated total solids, total white blood cell (WBC) count and differential WBC count. Each turtle was assigned a subjective tumor score ranging from 0 (no visible external tumors) to 3 (heavily tumored) that indicated the severity of FP. There was a progressive increase in monocytes and a decrease in all other hematologic parameters except heterophils and total numbers of white blood cells as tumor score increased. These data indicate that tumor score can relate to physiologic status of green turtles afflicted with FP, and that tumor score is a useful field monitor of severity of FP in this species.  相似文献   

9.
An adult squirrel monkey with a history of long-term exposure to microwave radiation was found at necropsy to have a malignant tumor of the right cerebral cortex. Gross examination revealed a mass with expanding borders in the right frontoparietal cortex with compression of the adjacent lateral ventricle. Microscopy revealed a tumor composed of sheets of moderate-sized cells, resembling an oligodendroglioma, with clear cytoplasm and central nuclei interrupted by delicate vasculature. Malignant features were present in the form of marked nuclear pleomorphism, frequent mitotic figures, and focal necrosis. A neuronal cell origin for this tumor was supported by immunohistochemical analysis, which revealed immunopositivity for neurofilament proteins and neuron-specific enolase. Staining for vimentin and glial fibrillary acid protein was negative, except in reactive astrocytes at the tumor margins and adjacent to intra-tumoral blood vessels. Antibody activity against Ki-67 antigen, a marker of rapidly proliferating tumor cells, and p53 oncoprotein was strongly positive, indicative of the aggressive and malignant nature of this tumor. The tumor was diagnosed as a cerebral primitive neuroectodermal tumor.  相似文献   

10.
In this study, we estimated interstitial histamine concentrations in normal and malignant tissues after a single intravenous (i.v.) injection of 0.5 mg/kg histamine dihydrochloride in the rat. The microdialysis technique was used to collect interstitial fluid from subcutis, liver and a NGW adenocarcinoma. Histamine was absorbed with equal efficiency to all tissues (t 1/2 AB 3.9-7.7 minutes) but maximum concentration (Cmax; nmol/l) of histamine was higher in liver (2,388 +/- 357) than in subcutis (951 +/- 125) (p < 0.01) and subcutaneous tumor (523 +/- 140) (p = 0.01) and, moreover, Cmax in liver tumor (1,752 +/- 326) was higher than in subcutaneous tumor (p = 0.01). The tl/2 elimination was significantly longer in subcutis and subcutaneous tumor than in liver and liver tumor. Area under the curve (AUC; mmol-min/l) for histamine was significantly lower in subcutaneous tumor (9.8 +/- 2.3) than in liver (17.6 +/- 1.9) (p = 0.03) and liver tumor (15.8 +/- 1.8) (p = 0.03). Local tissue blood flow as assessed by the 14C-ethanol method was not significantly altered by the histamine administration. In conclusion, after an i.v. injection of histamine dihydrochloride a higher maximum concentration and AUC of histamine was reached in liver and liver tumor than in subcutaneous tissues.  相似文献   

11.
Summary Lewis T241 fibrosarcoma, a syngeneic tumor in C57 BL/6J mice, was found to be poorly immunogenic. When tumor-bearing animals (TBA) were challenged with tumor cells either concomitantly or after excision of a growing tumor no protection was observed. In vivo (Winn) neutralization assays also showed a lack of tumor immunogenicity. However, in vitro studies showed that a significant proliferative response could be elicited from the spleen cells of TBA when these cells were cultured with either mitomycin-C-treated tumor cells or KCl tumor extract. Similarly, macrophage migration inhibition factor (MIF) was produced by TBA spleen cells upon incubation with KCl tumor extract, but no cell-mediated cytotoxicity to T241 target cells was observed with various lymphoid cell populations at any stage of tumor growth. Immunization of syngeneic animals with Vibrio cholerae neuraminidase(VCN)-treated, irradiated tumor cells alone or admixed with Freund's complete adjuvant (FCA) resulted in decreased tumor growth and fewer pulmonary metastases following challenge with 106 tumor cells. No complete tumor rejection was observed. In contrast, 13 of 16 animals immunized with irradiated tumor cells admixed with FCA rejected 105 tumor cells. Animals that grew tumors had significantly reduced tumor growths and pulmonary metastases. Lymph node and peritoneal exudate cells (PEC) of immunized animals showed significant cytotoxicity to T241 cells.  相似文献   

12.
目的建立人卵巢癌SCID小鼠移植瘤模型和相应体外细胞系.方法将病理证实的人卵巢浆液性乳头状腺癌手术切除标本移植于SCID小鼠皮下,成瘤后行鼠间传代,取移植瘤细胞体外分离培养、传代和建系,并应用细胞、分子生物学手段对移植瘤和建系细胞进行一系列生物学特性检测.结果历时14个月传至5代,皮下移植瘤存活率为90%,持续6个月,体外建系(OVA-319)细胞生长稳定.镜下观察组织形态学和超微结构符合原肿瘤组织基本特征;染色体分布在12~46条之间,多为异倍体,显示人类肿瘤异常染色体;流式细胞术和RT-PCR技术分析原代、体内移植瘤和OVA-319细胞结果一致,表现为瘤细胞生长活跃、细胞周期分布相仿,MAGE-2基因在mRNA水平异常表达.结论人卵巢癌SCID小鼠移植瘤模型和OVA-319细胞系为人类肿瘤的研究提供了良好的实验材料.  相似文献   

13.
In China, the giant panda (Ailuropoda melanoleuca) is an endangered and rare national first-class protected animal with important research and ecological value. Tumor poses a serious threat to animal health. In this paper, a giant panda testicular tumor was diagnosed by macro and histopathologic examination, which aims to supplement the relevant data of giant panda tumor research, and also provides a reference for the diagnosis of giant panda tumor. Macro examination found that the testis was swollen about twice and the sheath was intact. The parenchyma was uniform in texture, grayish white with gray yellow caseous necrosis in the center. Histopathologically, the normal tissue structure of testis was lost and eroded by tumor cells. The tumor cells were similar to spermatogonia, round or polygonal, but with larger size, hyperchromatic cytoplasm and increased nuclear chromatin. Pathologic mitotic phases were found in tumor cells, and necrosis lesions with different sizes are distributed in tumor tissues. On the basis of macro and histopathologic examination results, the tumor was diagnosed as seminoma (also known as germ cell carcinoma), which is the first report of testicular seminoma in the giant panda.  相似文献   

14.
Variation in the distribution of trace elements in hepatoma   总被引:3,自引:0,他引:3  
There are many reports of reduction of zinc level and rise of copper level in serum of patients with liver disease. However, there are a few reports that compare the trace elements in tumor tissues and nontumor tissues of the liver with hepatoma. We studied trace element distribution in tumor tissues and nontumor tissues of liver with hepatoma and compared them with data from normal liver tissues. Zinc (Zn), copper (Cu), selenium (Se), cadmium (Cd), mercury (Hg), and iron (Fe) were chosen as the trace elements to be observed. We observed falls of Zn, Cd, and Hg levels in tumor tissues and the rise of Cu level as a result of this investigation. Zn, Cd, and Hg levels in tumor tissues were significantly lower than those in nontumor tissues and Zn, Cd, and Hg levels in nontumor tissues were significantly lower than in normal liver tissues. This tendency was clearer for Cd and Hg than for Zn. Although the distribution of Cu was not significant, a distribution contrary to that of Zn was shown. These findings indicate that the distribution of Zn, Cd, and Hg can serve as supportive evidence that could be useful as a tumor marker. Selenium showed almost the same accumulation tendency among tumor tissues, nontumor tissues, and normal livers. Although correlation was observed among most metals in the normal liver, there was almost no correlation in tumor tissues.  相似文献   

15.
A carcinoid tumor of the cervix in a 40-year-old woman was studied by cytology, histology, electron microscopy, immunohistochemistry and hormonal analysis. The preoperative cytologic and histologic findings strongly suggested a carcinoid tumor of the cervix. The serum serotonin level was elevated; immunohistochemical studies demonstrated the presence of serotonin in the cytoplasm of the tumor cells. Following radical hysterectomy, the concentration of serotonin was measured in the excised tumor; it was about 20 times higher than the level seen in normal cervical tissue, confirming that the tumor was a serotonin-secreting carcinoid of the uterine cervix.  相似文献   

16.
目的观察直接注入法和瘤块种植法制作Wistar大鼠肝癌模型的差异。方法采用大鼠含有Walker-256肿瘤细胞的腹水离心洗涤后接种于另一组大鼠的后腿后外侧皮下,待肿瘤长到直径约为1.0em,取下肿瘤并切成1.0-2.0mm^3大小。然后将瘤块接种于15只大鼠的肝叶上;另一组(15只)按上述方式将癌性腹水接种于正常大鼠的肝叶上;两组均在第7天后采用CT和开腹后游标卡尺分别测量种植性肝癌的直径。结果腹水直接注射法与瘤块种植法的肿瘤成瘤率分别为:86.7%和80%,两者并不具有统计学意义(P〉0.05)。第7天时,直接注射法所形成肿瘤的直径大于瘤块种植法的肿瘤(P〈0.05)。但瘤块法所引起的腹腔转移的可能性要少于腹水直接种法。结论直接注射法和瘤块种植法制作大鼠肝癌模型均可以满足临床实验研究的需要,但直接注射法的成瘤时间短,腹腔转移可能性也大;瘤块种植法成瘤时间略长,但腹腔转移可能性少于直接法。  相似文献   

17.
Summary A suspension of heat-killed Aspergillus fumigatus mycelium inhibited the growth of a chemically-induced mouse bladder tumor (MBT). Tumor growth was inhibited when the mycelium was injected into mice in a mixture with the tumor cells, when injected into growing tumors, and when introduced IP at the time tumor cells were injected into the hind leg muscle. In the concentrations that affected tumor growth no toxicity of the fungus preparation was observed. The fungal suspension was more effective against MBT than a Corynebacterium parvum strain known to be a potent biologic response modifier. A significant increase in the number of mouse peritoneal exudate cells (PEC) was noted following inoculation with the mycelium. The induced PEC were cytotoxic to the tumor cells in vivo, suggesting that at least part of the tumor inhibition by the mycelium is host-mediated.  相似文献   

18.
Pathological examination was performed on a male 196-day-old Sprague-Dawley rat with hindrance of the motility. A tumor was found to locate in the right lateral ventricle. It was poorly demarcated, and was reddish gray in color. The tumor cells were pleomorphic, fusiform or polygonal in shape and varied in size, sometimes with formation of pseudorosettes. The tumor was diagnosed as ependymoma.  相似文献   

19.
陈量  孙立  袁胜涛 《生物磁学》2011,(21):4175-4177
肿瘤的微环境对肿瘤的发生,发展具有重要的意义。实体瘤中除肿瘤细胞外存在大量的非肿瘤细胞,如肿瘤闻质细胞、成纤维细胞、血管内皮细胞、免疫细胞、脂肪细胞等等,这一系列的细胞与肿瘤细胞相互作用,通过一系列的因子分泌而促使肿瘤的进一步的恶化,目前传统的抗肿瘤药物研究往往局限于肿瘤细胞本身而忽略了肿瘤周围的细胞作用,使得肿瘤久治不愈。将来的药物开发应该围绕肿瘤细胞为主体的同时,兼顾微环境中的其他细胞,多靶点治疗肿瘤,真正实现肿瘤的治愈。  相似文献   

20.
The antitumor effect of extracts obtained from the fruit body of Agaricus blazei Murill was examined in a double-grafted tumor system, in which BALB/ c mice received simultaneous intradermal injections of Meth-A tumor cells in both the right (106 cells) and left flank (2 × 105 cells), and were then injected with 5 mg of extracts of A. blazei in the right tumor on days 3, 4 and 5. Intratumoral administration of ethanol-soluble (Fraction 1), water-ethanol-soluble (Fraction 2), ammonium oxalate-soluble (Fraction 3) and ammonium oxalate-insoluble (Fraction 4) fractions resulted in inhibition of tumor growth, with Fraction 3 showing the most tumoricidal activity, producing regression of the right tumor and inhibitition of growth of the left, non-injected tumor. The maximum effect was obtained using 0.5 mg of Fraction 3 and this amount was used in subsequent experiments. The antitumor effect of intratumorally administered Fraction 3 was enhanced by oral ad lib administration of feed containing 0.083% of Fraction 3. When immunized spleen cells from mice that had been cured by intratumoral administration of 0.5 mg of Fraction 3 were directly injected (2 × 107 cells/mouse) into the Meth-A tumor, tumor growth was inhibited. The tumor cells on day 7 from the Fraction 3-treated right tumor and from the left tumor were cultured for 24 h and their culture supernatants were assayed for neutrophil or macrophage chemotactic activity. Significant macrophage chemotactic factor activity was detected in the culture media from the left tumor tissue. Serum levels of immunosuppressive acidic protein (IAP), produced by activated macrophages and neutrophils, increased transiently soon after intradermal injection of 0.5 mg of Fraction 3. These results suggest that regression of the left non-injected tumor was due to an immune reaction, involving induction of cytotoxic cells in the spleen, and the release of chemotactic factors in the distant tumor.  相似文献   

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