CXCR4、CCR7及其配体与非小细胞肺癌器官特异性转移的研究进展

肿瘤的转移是恶性肿瘤最重要的生物学特性之一,具体的机制目前仍未明确.研究证明,肿瘤的转移不是随意的,而是具有选择性的,即器官特异性.     

癌细胞和人血管内皮粘附与器官特异转移相关

目的：检测5种不同类型的人肿瘤细胞系与4种不同采源的人微血管内皮的粘附，并探讨粘附作用与肿瘤器官特异性转移的相关性。方法：人微血管内皮培养形成完全汇合的静止内皮单层后，与Calcein AM标记人肿瘤细胞系进行粘附测定。结果：8种食管癌细胞系中，有6种与人肺内皮的粘附显著强于与肝窭内皮的粘附；7种食管癌细胞系与人正常食管厦食管癌内皮的粘附均强于与人正常肺内皮和肝窭内皮的粘附．这与食管癌临床上肺转移多于肝转移，但相对于远处转移，更倾向于食管内侵袭播散性转移的特征一致。4种结肠癌细胞系与人肝窦内皮粘附均显著强于与人肺内皮和食管正常内皮．与临床上结肠癌主要发生肝转移的特征一致。肝癌、胃癌、肺癌细胞系与内皮的粘附也与临床上转移特征一致。结论：不同组织类型肿瘤细胞与器官采源不同的人内皮细胞的粘附能力具有明显的组织特异性和选择性，且这种粘附特性与临床上肿瘤的组织特异性转移密切相关。阻断这种粘附作用有可能治疗肿瘤转移。     

Regulation of Gelatinase Production in Metastatic Renal Cell Carcinoma by Organ-specific Fibroblasts

We have recently established a human renal cell carcinoma KG-2 line that is tumorigenic in the subcutis (ectopic) and kidney (orthotopic) of nude mice but spontaneously metastasizes to the lung only after orthotopic implantation. KG-2 cells growing in the kidney (orthotopic) and lung metastases secreted higher levels of gelatinase than did cells growing in the subcutis (ectopic). We examined whether organ-specific fibroblasts play a role in the regulation of gelatinase production and invasion by renal carcinoma cells. The gelatinase level in the culture supernatants of KG-2 cells was increased by their cultivation with mouse kidney or lung fibroblasts. In contrast, cocultivation of KG-2 cells with mouse skin fibroblasts resulted in a significant reduction of gelatinase activity. Similar results were obtained by culturing KG-2 cells in the media conditioned by the different mouse fibroblasts. We, therefore, investigated effects on KG-2 cells of cytokines and growth factors known to be produced by fibroblasts of various origins. Of ten cytokines and growth factors tested, basic fibroblast growth factor, hepatocyte growth factor, and transforming growth factor-β₁ (TGF-β₁) stimulated gelatinase expression by the cultured KG-2 cells. Parallel immunohistochemical analyses revealed that mouse kidney and lung fibroblasts produced higher levels of TGF-β₁ than did skin fibroblasts. These results indicate that gelatinase production by KG-2 renal cell carcinoma cells is influenced by the organ microenvironment. Specifically, organ-specific fibroblasts regulate the production of degradative enzymes by KG-2 cells and, hence, profoundly influence their invasive and metastatic capacity.     

Organotropic Chemopreventive Effects of n-3 Unsaturated Fatty Acids in a Rat Multi-organ Carcinogenesis Model

Organotropic chemopreventive effects of n‐3 unsaturated fatty acids were studied using a multi‐organ carcinogenesis model in male rats. Rats were treated with diethylnitrosamine (DEN), N‐methyl‐N‐nitrosourea (MNU), N‐butyl‐N‐4‐hydroxybutylnitrosamine (BBN), 1,2‐dimethylhydrazine (DMH) and dihydroxy‐di‐n‐propylnitrosamine (DHPN) during the first 7 weeks, and then given unsaturated fatty acid (UFAs), docosahexaenoic acid (n‐3, C_22:6) (DHA), eicosapentaenoic acid (n‐3, C_20:5) (EPA), linoleic acid (n‐6, C_18:2) (LA) or oleic acid (n‐9, C_18:1) (OA) at a dose of 1.0 ml/rat, 3 tunes a week by gavage for the consecutive 30 weeks. All rats were fed a low LA basal diet throughout the experiment and a calorie‐restricted basal diet during the period of UFAs feeding administration. DHA significantly reduced tumor size and numbers in the large intestine as compared to OA treatment. Furthermore, DHA showed a tendency to inhibit carcinogenesis in the small intestine and lung. EPA also showed a tendency to inhibit intestinal carcinogenesis. On the other hand, LA showed a tendency to inhibit lung carcinogenesis, but to promote large intestinal carcinogenesis. However these UFAs did not influence preneoplastic and neoplastic lesion development in the liver, kidney, and urinary bladder. Levels of the administered fatty acids were clearly increased in the serum and organs. In contrast, arachidonic acid (AA) levels in the large and small intestines and liver were markedly decreased by treatment with DHA and EPA. Decreased levels of AA in the large intestine correlated well with tumor incidence, although the number of glutathione S‐transferase‐positive (GST‐P⁺) foci showed an inverse correlation with AA levels. The data thus provide evidence that an organotropism exists with regard to the influence of UFAs on carcinogenesis, which correlates with reduction of tissue AA levels in the target organs.     

肺癌纵隔淋巴结转移规律的分析

目的：探讨肺癌纵隔淋巴结转移的规律与特点。方法：对358例肺癌行肺切除加淋巴结廓清术，对其中132例N2肺癌病例的281组转移性纵隔淋巴结进行临床病理分析。结果：两组以上N2转移占62.1%，跳跃式转移占12.1%，左侧肺癌N2转移发生率较高的依次为5，7，6组淋巴结，右侧肺癌N2转移发生率较高的依次为4，7，3组淋巴结；瘤体越大N2转移发生率越高，肺癌分化程度越差，N2转移发生率越高，病理类型不同，N2转移发生率分别为，小细胞癌80.0%，腺癌45.1%，大细胞癌33.3%，鳞癌24.0%，结论：对N2肺癌行广泛，全面的纵隔淋巴结清扫是十分必要的。     

Organotropic chemopreventive effects of n-3 unsaturated fatty acids in a rat multi-organ carcinogenesis model.

Organotropic chemopreventive effects of n-3 unsaturated fatty acids were studied using a multi-organ carcinogenesis model in male rats. Rats were treated with diethylnitrosamine (DEN), N-methyl-N-nitrosourea (MNU), N-butyl-N-4-hydroxybutylnitrosamine (BBN), 1,2-dimethylhydrazine (DMH) and dihydroxy-di-n-propylnitrosamine (DHPN) during the first 7 weeks, and then given unsaturated fatty acid (UFAs), docosahexaenoic acid (n-3, C(22:6)) (DHA), eicosapentaenoic acid (n-3, C(20:5)) (EPA), linoleic acid (n-6, C(18:2)) (LA) or oleic acid (n-9, C(18:1)) (OA) at a dose of 1.0 ml/rat, 3 times a week by gavage for the consecutive 30 weeks. All rats were fed a low LA basal diet throughout the experiment and a calorie-restricted basal diet during the period of UFAs feeding administration. DHA significantly reduced tumor size and numbers in the large intestine as compared to OA treatment. Furthermore, DHA showed a tendency to inhibit carcinogenesis in the small intestine and lung. EPA also showed a tendency to inhibit intestinal carcinogenesis. On the other hand, LA showed a tendency to inhibit lung carcinogenesis, but to promote large intestinal carcinogenesis. However these UFAs did not influence preneoplastic and neoplastic lesion development in the liver, kidney, and urinary bladder. Levels of the administered fatty acids were clearly increased in the serum and organs. In contrast, arachidonic acid (AA) levels in the large and small intestines and liver were markedly decreased by treatment with DHA and EPA. Decreased levels of AA in the large intestine correlated well with tumor incidence, although the number of glutathione S-transferase-positive (GST-P(+)) foci showed an inverse correlation with AA levels. The data thus provide evidence that an organotropism exists with regard to the influence of UFAs on carcinogenesis, which correlates with reduction of tissue AA levels in the target organs.     

Enhancement of Tumor Proliferation by Cyclosporine A in Early Phase of Experimental Hepatic Metastasis

The effect of cyclosporine A (CsA) on in vivo growth of hepatic metastasis was studied. Murine colon 38 tumor cells (1 × 10⁵) were inoculated via the superior mesenteric vein. Mice were grouped depending on CsA dosage and time schedules: Group A: CsA 30 mg/kg body weight on the 7, 8 and 9th post tumor inoculation days hy gavage; Group B: CsA 15 mg/kg body weight 30 min before tumor inoculation and 2 times more at 24 h intervals; Group C: CsA 30 mg/kg body weight at the same dose timing as Group B. Measurement of the diameter of the largest tumor serially by weekly laparotomy up to 4 weeks revealed that the tumor growth rates were significantly greater in Groups B and C than those in Group A or the control (without CsA). The mean tumor doubling times in the control, and Groups A, B and C were 2.2±1.3, 2.0±0.5, 1.5±0.4 and 1.3±0.8 days, respectively. The mean tumor numbers of hepatic metastasis were 13.2±8.3, 11.3±7.3, 19.4±8.7 and 19.6±6.8, respectively. Values of tumor proliferation index obtained by bromodeoxyuridine immunohistochemistry were 10.0±6.1%, 14.9±8.0%, 28.6±8.2% and 30.1±12.4%, respectively, with significant differences (Groups B and C vs. A or control, P <0.05). In vitro MTT assay showed that cell viability rates were greater than 100% in the medium containing CsA concentrations of less than 10⁻⁷ mol/liter. However, a cytostatic effect of CsA was apparent at higher concentrations. In contrast to the previous in vivo finding of a cytostatic effect of CsA on tumor cells, we found a cytoproliferative action when CsA was administered early in the course of metastatic tumor implantation in the liver. The mechanism of cytoproliferative effect of CsA is unknown but may involve multiple factors.     

Organ-specific effects of 1,2-dimethylhydrazine in hamster

Uptake and metabolism of the carcinogen 1,2-dimethylhydrazine (DMH) were compared in isolated epithelial cells from the colon and the small intestine. A new method was developed to separate colonic epithelial cells into surface columnar cells and crypt cells without the use of any proteolytic enzymes. Colonic columnar cell-enriched fraction exhibited DMH metabolism two to three times higher than that of crypt cells. The carcinogen binding was much lower in the small intestine as compared to the colon. In the small intestine, the crypt cell-enriched fraction showed higher carcinogen binding as compared to villus cells. Pyrazole was found to inhibit DMH binding by isolated small intestinal and colonic epithelial cells. The extent of inhibition was maximum in cells showing the greatest ability to incorporate DMH.     

pH值调控肿瘤细胞生长转移的机制

实体瘤存在一个显著的特征是肿瘤胞内呈碱性和胞外呈酸性的微环境,这种酸性微环境能促进肿瘤细胞的生长、侵袭转移.调节肿瘤酸性微环境的主要因子是膜离子交换体,这些离子交换体如NHE和VHA不仅是肿瘤酸性微环境的主要调节者,而且能促进肿瘤细胞的生长转移.通过调节肿瘤胞内外pH值变化可以抑制肿瘤细胞生长转移,但pH值的变化对肿瘤细胞生长转移的调控机制尚不清楚.全文对肿瘤细胞转移的发生机制、肿瘤酸性微环境的形成和膜离子交换体对其调节作用以及三者的关系进行阐述.     

Comprehensive Network Analysis of the Molecular Regulation Mechanism for Breast Cancer Metastasis

Breast cancer is one of malignant severe diseases that cause cancer death in women. Although research about the pathogenesis and studies about treatment mechanisms in breast cancer have become clear focuses, we have no clear conclusion yet. Therefore, this research is based on a modular approach to explore key factors and molecular mechanisms that affect breast cancer metastasis. First of all, it is necessary to download breast cancer-related data on the GEO database, and we analyzed the difference between primary tumors and metastatic lesions to obtain differential gene expression profiles. On this basis, a series of bioinformatics analyses were performed to comprehensively, and they were presented to identify critical regulators in breast cancer metastasis. We have obtained a total of five co-expression modules, among which HECW1, FBN1, and other genes have effective regulation in dysfunction modules, and thus they would be recognized as driving genes for breast cancer metastasis. Module genes were significantly enriched in biological function, for instance, leukocyte-cell adhesion and negative regulation in the immune system process. At the same time, it substantially regulates signaling pathways, for example, fatty acid degradation, synthesis, and degradation of ketone bodies, and amino acid metabolism. Finally, we identified ncRNA pivots (including FENDRR, miR-19a-3p, and miR-26b-5p) and TF pivot (including NFKB1 and SP1) to regulate dysfunction modules significantly. Our study identified the coexpression network of genes involved in breast cancer metastasis. These results may be helpful to reveal the gene modules and regulatory factors of breast cancer. Importantly, we identified a long non-coding FENDRR that inhibits breast cancer metastasis through a fatty acid degradation signaling pathway, providing new directions and targets for subsequent studies.     

Metformin Suppresses Ovarian Cancer Growth and Metastasis with Enhancement of Cisplatin Cytotoxicity In Vivo

Ovarian cancer is the most lethal gynecologic cancer in women. Its high mortality rate (68%) reflects the fact that 75% of patients have extensive (>stage III) disease at diagnosis and also the limited efficacy of currently available therapies. Consequently, there is clearly a great need to develop improved upfront and salvage therapies for ovarian cancer. Here, we investigated the efficacy of metformin alone and in combination with cisplatin in vivo. A2780 ovarian cancer cells were injected intraperitoneally in nude mice; A2780-induced tumors in nude mice, when treated with metformin in drinking water, resulted in a significant reduction of tumor growth, accompanied by inhibition of tumor cell proliferation (as assessed by immunohistochemical staining of Ki-67, Cyclin D1) as well as decreased live tumor size and mitotic cell count. Metformin-induced activation of AMPK/mTOR pathway was accompanied by decreased microvessel density and vascular endothelial growth factor expression. More importantly, metformin treatment inhibited the growth of metastatic nodules in the lung and significantly potentiated cisplatin-induced cytotoxicity resulting in approximately 90% reduction in tumor growth compared with treatment by either of the drugs alone. Collectively, our data show for the first time that, in addition to inhibiting tumor cell proliferation, metformin treatment inhibits both angiogenesis and metastatic spread of ovarian cancer. Overall, our study provides a strong rationale for use of metformin in ovarian cancer treatment.     

Organ-specific biotransformation of ormaplatin in the Fischer 344 rat

We examined the intracellular biotransformation products of ormaplatin [(d,l-trans)1,2-diaminocyclohexanetetrachloroplatinum(IV)] (formerly called tetraplatin) in liver, kidney, spleen, small intestine, and plasma of the adult male Fischer 344 rat. Previous studies have established that the rank order of ormaplatin toxicity in Fischer 344 rats is spleen gastrointestinal tract > kidney liver. Animals were given tritium-labelled drug i.v. at 12.5 mg/kg, and tissues were harvested 30 min later. The kidney was found to concentrate total and cytosolic platinum to a greater extent than any of the other tissues. The absolute amount of cytosolic platinum, in micrograms per gram tissue, that was irreversibly bound to protein and/or other macromolecules was also greatest in the kidney. However, when the amount bound was expressed as a percentage of the total cytosolic platinum, the kidney was significantly lower than any other tissue. Of the various low molecular mass platinum biotransformation species characterized, by far the most abundant were complexes of platinum with the sulfur-containing molecules cysteine, methionine, and glutathione (GSH). There was more of the methionine complex in the blood plasma than in any of the tissues except for the spleen. No significant differences among the tissues were detected for the dichloro, cysteine, methionine, or the GSH complexes. The tritium-labelled diaminocyclohexane (DACH) carrier ligand appeared to remain stably bound to the platinum while in the plasma, as there was less free DACH ligand detected in plasma ultrafiltrate than in any tissue ultrafiltrate. Among the tissues, the free DACH levels were in the range of 20% of the radioactivity recovered from the HPLC column and were not significantly different. Consequently, neither biodistribution nor tissue-specific biotransformation of ormaplatin provides a ready explantation for the tissue specificity of ormaplatin toxicity in Fischer 344 rats. However, in kidney there was much less of the reactive PtCl₂(DACH) species than has previously been reported for the corresponding Pt(NH₃)₂Cl₂ species in cisplatin-treated rats. Thus, these data suggest a possible explanation for differences in nephrotoxicity induced by cisplatin versus that by ormaplatin.Abreviations DACH (d,l)Trans-1,2-diaminocyclohexane - PtCl ₂ (DACH) (d,l)trans-1,2-diaminocyclohexanedichloroplatinum(II) - DDTC diethyldithiocarbamate - WR-2721 S-2-(3-aminopropylamino)-ethylphosphorothioic acid - HPLC high-performance liquid chromatography - RP reverse phase chromatography - SCX strong cationexchange chromatography - AAS flameless atomic absorption spectroscopy - LSC liquid scintillation counting - MWCO molecular weight cutoff - GSH reduced glutathione This work was supported by National Institutes of Health Grants CA55326 and ES07126.     

乙酰肝素酶在乳腺癌侵袭转移中的作用及调控机制*

乙酰肝素酶（Heparanase ,HPSE）是目前发现的哺乳动物细胞中唯一能降解细胞外基质和基底膜中硫酸肝素蛋白多糖侧链—硫酸乙酰肝素的内源性糖苷酶,是目前抗肿瘤转移的理想靶点。HPSE在乳腺癌中常有高表达,并与肿瘤大小和淋巴结转移等密切相关。体外研究表明,乳腺癌细胞中HPSE启动子活性增高,转染HPSE的乳腺癌细胞在体内成瘤后,其肿瘤体积、重量、微血管密度以及癌细胞存活时间均明显高于阴性对照组。应用反义核酸技术或RNA干扰技术封闭或沉默HPSE基因表达后,乳腺癌细胞黏附和侵袭能力显著降低,表明HPSE在乳腺癌侵袭转移中发挥极其重要的作用。HPSE在乳腺癌侵袭转移中受多种机制调控,主要有：雌激素与其受体结合后作用于HPSE基因特定区域,从而提高HPSE转录活性,增强其基因和蛋白的表达;HPSE可使破骨细胞刺激因子产生增加,从而导致骨质溶解破坏,为乳腺癌骨转移奠定基础;HPSE诱导循环淋巴细胞产生刺激因子,从而促进乳腺癌的侵袭转移。此外,HPSE基因还受p53基因、ETS 基因、EGR 1 基因、PI-88因子、COX-2 等的调控。本文就HPSE在乳腺癌中的表达状况、在侵袭转移中的作用及调控机制进行综述。