甲酰肽受体家族受体与恶性肿瘤

甲酰肽受体家族受体包括甲酰肽受体（FPR）、类甲酰肽受体1和类甲酰肽受体2是主要表达在吞噬细胞表面的一类七次跨膜、G蛋白偶联受体。这些受体被相应的激动剂激活后，能活化吞噬细胞，引起细胞的趋化移动和炎症介质的释放等生物学效应，从而在天然免疫和炎症反应中发挥重要作用。近年来，人们发现甲酰肽受体家族受体也高表达于某些恶性肿瘤细胞的表面，且与这些肿瘤的发生、发展、转移以及治疗有着密切的关系，这无疑揭示了甲酰肽受体家族受体一个新的重要作用，值得深入研究和探讨。     

Malignant progression of B16 melanoma cells induced in vitro by growth factors produced by highly malignant cells

Four mouse B16 melanoma subclones (G3.15, G3.5, G3.12 and G3.26) exhibit progressively greater growth capacity in vitro and in vivo. Previously, non-metastatic G3.15 cells were sequentially converted, in monolayer cultures, to the moderately-metastatic G3.5 cells, and then to a highly-metastatic G3.5^* phenotype. Both conversions were induced by hypoxia followed by confluence, and also occurred in tumors. G3.5^* cells were comparable with, yet distinguishable from, G3.12 cells in being growth-autonomous in culture. In this study, the presumption that rapidly-growing G3.26 cells represented the ultimate progression step in this clonal system was examined. Both G3.12 and G3.5^* cells converted in vitro to the G3.26 phenotype during growth in serum-free medium conditioned by G3.26 cell growth. By selective filtration of conditioned medium and characterization of the stability of growth- and conversion-promoting activities, three distinct activities were found to promote a two-step G3.12 to G3.26 phenotype conversion: (1) a < 10 kDa filtrate stimulated slight attachment and proliferation of G3.12 cells, effects that were reversible, partly attributable to accumulated lactate, and fully mimicked by medium acidification to pH 6.5; (2) medium acidification, together with a heat- and acid-stable but partially trypsin-sensitive > 10 kDa activity, induced G3.12 G3.5^* conversion that resulted in acquisition of growth autonomy; and (3) a heat-, acid- and trypsin-sensitive > l0 kDa activity induced G3.5^* G3.26 conversion, characterized by anchorage-independent growth in soft agar, and potent lung colonization following intravenous injection. Phenotype analysis of G3.12 tumors and lung metastases revealed that G3.5^*-like cells were regularly present in tumors and metastases, whereas G3.26-like cells occurred almost exclusively in large lung metastases. While G3.12 cells might convert to G3.5^* cells in order to disseminate, G3.26 cells are apparently not involved in metastatic spread but probably account for the rapid growth of established metastases.     

Adhesion of carcinoma cells to rat hepatocytes and rat fibronectin is inhibited by the OPAR monoclonal antibody,which is directed against a rat liver-specific carbohydrate epitope

The OPAR mouse monoclonal antibody (mAb) directed against rat hepatocytes was previously shown to inhibit adhesion of TA3/Ha mammary carcinoma cells to hepatocytes. The antigen is abundantly present at the surface of hepatocytes beneath the endothelium of liver capillaries where we have observed invasion of carcinoma cells to occur. The OPAR mAb reacted with three major bands on a Western blot of liver plasma membrane proteins. The same proteins were also seen upon immunoprecipitation from iodinated liver plasma membrane proteins. We have isolated OPAR antigens by lectin wheat germ agglutinin (WGA) and OPAR affinity chromatography. Amino acid sequence analysis revealed that two of the bands were 1-macroglobulin and C4-binding protein, which are serum components produced by hepatocytes. The presence of the epitope on distinct proteins and our previous observation that it can be detected in the Golgi apparatus but not in the endoplasmic reticulum, suggested that OPAR reacts with a liver-specific glycoconjugate. Loss of OPAR reactivity after neuraminidase and N-glycosidase F treatment showed that the epitope contains sialic acid residues on N-linked sugar moieties. OPAR also reacted with rat fibronectin, and inhibited adhesion of TA3/St cells to fibronectin. This explains the inhibition by the OPAR mAb of TA3/St cell adhesion to hepatocytes, which we have shown to be due mainly to interaction with hepatocyte surface-associated fibronectin. However, adhesion of the related TA3/Ha cells to hepatocytes, which is mediated by the ₆P4 integrin, and does not involve binding to fibronectin, is also inhibited. This suggests that ₆₄ on liver-metastasizing carcinoma cells binds to an OPAR epitope-carrying glycoprotein produced by hepatocytes.     

Biological properties and gene expression associated with metastatic potential of human osteosarcoma

Lung metastasis has a great influence on the prognosis of patients with osteosarcoma. We previously established two high-metastatic sublines, M112 and M132, from the HuO9 human osteosarcoma cell line by in vivo selection. In this study, we newly isolated a high-metastatic subline, H3, and three low-metastatic sublines, L6, L12 and L13, from HuO9 by the dilution plating method. Three high-metastatic sublines produced more than 200 metastatic nodules in the lung, while three low-metastatic sublines produced no or few nodules after injection of 2 × 10⁶ cells into the tail vein of nude mice. There were significant differences in the motility and invasiveness between high- and low-metastatic sublines, whereas the growth rates in vitro and the tumorigenicity in vivo showed no correlation with their metastatic abilities. Early adherence to culture plates was significantly lower in two of three low-metastatic sublines, which occupied smaller surface areas on the culture plates than other sublines did. Comparison of the expression of 637 cancer-related genes by cDNA microarray revealed that seven genes were differentially expressed between high- and low-metastatic sublines. Among them, five genes (AXL, TGFA, COLL7A1, WNT5A, and MKK6) were associated with adherence, motility, and/or invasiveness. These results suggest that the differences in motility/invasiveness and adhesive abilities are key determinants of lung metastasis in osteosarcoma. This revised version was published online in July 2006 with corrections to the Cover Date.     

The developmentally regulated neural crest-associated glycotope HNK-1 predicts metastasis in cutaneous malignant melanoma

Aberrant glycosylation is a common feature of metastatic sub-clones of malignant tumours and in uveal melanoma in particular, the HNK-1 glycotope has been positively correlated with poor prognosis. So far, no such correlation has been investigated in cutaneous melanoma. In order to do so, HNK-1 expression was evaluated immunohistochemically in 100 primary cutaneous melanomas and correlated with metastasis after up to 10-years' follow-up. Furthermore, HNK-1 expression was analysed in metastatic deposits (19 distant cutaneous metastases and six sentinel lymph node metastases), as well as in benign nevi. Kaplan-Meier analysis revealed a positive association between HNK-1 expression and metastasis (p < 0.005) and multivariate Cox regression analysis adjusted for the standard prognostic markers ulceration and vertical tumour thickness confirmed HNK-1 expression as an independent prognostic marker. HNK-1 expression was preserved in 42% of the distant cutaneous metastases, but metastatic cells in lymph nodes were devoid of HNK-1 immunoreactivity. None of the benign pigmented lesions exhibited HNK-1 immunoreactivity. Expression of the HNK-1 glycotope in cutaneous malignant melanoma is an independent prognostic marker of metastasis. Differential HNK-1 expression at the metastatic sites implies that its expression is modulated by the surrounding environment. As HNK-1 is also transiently expressed during migration of melanocyte precursor cells derived from the neural crest, recapitulation of this transient expression might occur during metastatic spread of cutaneous malignant melanoma.     

不同转移特性瘤细胞系的筛选及其生物学特性

目的：探讨与肿瘤转移相关的某些生物学特性。方法：将小鼠乳腺癌Ｃａ７６１－ＦＰ８／Ｌ和Ｃａ７６１－ＦＬ１０／Ｌ经体内筛选得到细胞系Ｃａ７６１－Ｐ５Ｂ和Ｃａ７６１＝Ｌ６Ｂ，并观察其瘤细胞与凝集反应、靶器官组织条件培养基对瘤细胞真挚化作用等，结果：Ｃａ７６１－Ｐ５Ｂ具有高肺转移、低淋巴结转移特性，Ｃａ７６１－Ｌ５Ｂ具有低肺、低淋巴结转移特性。两个瘤细胞系的细胞表面的糖基表达，对条件培养的趋化反应不同。结     

Inhibition of experimental metastasis and cell adhesion of murine melanoma cells by chondroitin sulfate-derivatized lipid, a neoproteoglycan with anti-cell adhesion activity

Chondroitin sulfate dipalmitoylphosphatidylethanolamine (CS-PE), when immobilized onto substratum, inhibited the adhesion of B16F10 mouse melanoma cells to fibronectin-coated dishes (anti-adhesion activity). CS-PE showed the most potent anti-adhesion activity for the melanoma cells among various GAG-PEs. CS-PE also inhibited the adhesion of B16F10 cells to Matrigel and the invasion of the cells into Matrigel. In the in vivo system of experimental metastasis, administration of B16F10 cells with CS-PE into C57BL/6 mice significantly inhibited lung metastasis. The inhibition degree of CS or hyaluronic acid-PE was lower than CS-PE. CS-PE administered intravenously into mice before the injection of B16F10 cells also inhibited metastasis. Pretreatment of B16F10 cells with CS-PE caused some but a lower degree of inhibition. When CS-PE was injected intravenously into mice, more binding in the lung was found than when CS was injected. CS-PE but not CS inhibited the retention in the lung of fluorochrome-labeled B16F10 cells when injected intravenously into mice. Since there was no significant effect of CS-PE on the viability and growth of B16F10 cells, the results suggest that CS-PE immobilized onto the subendothelial matrix may prevent melanoma cells from adhering to the subendothelial substrata of lung capillaries and inhibit subsequent invasion processes of metastasis.     

Evidence for the causal role of endogenous interferon-alpha/beta in the regulation of angiogenesis,tumorigenicity, and metastasis of cutaneous neoplasms

Primary tumor growth and metastasis depend on angiogenesis, which is determined by the balance between proangiogenic and antiangiogenic molecules. Interferon (IFN)-α and -β inhibit angiogenesis through downregulation of interleukin-8, matrix metalloproteinase-9, and basic fibroblast growth factor. To provide evidence for the causal role of IFN-α/β in the induction of neoplasms, their angiogenesis, and hence, progressive growth, we carried out experiments using 129S6 IFN-α/β receptor −/− mice back-crossed to BALB/c nude mice. Subcutaneous angiogenesis was determined following implantation of gelfoam sponges containing 0.4% agarose and several proangiogenic molecules. Tumorigenicity and production of lung metastasis were determined subsequent to subcutaneous and intravenous injections, respectively, of highly metastatic A375SM human melanoma cells. Carcinogenesis was induced by chronic exposure of mice to UVB radiation (5 kJ/m², 3 times/week). Angiogenesis, tumorigenicity, and production of metastasis, as well as development of autochthonous skin tumors, were all accelerated in IFN-α/β receptor −/− mice as compared to control mice. Collectively, the data show that inability to respond to endogenous IFN-α/β (through a mutation in the IFN-α/β receptor) leads to increased susceptibility to carcinogenesis, enhanced angiogenesis, tumorigenicity, and metastasis. This revised version was published online in July 2006 with corrections to the Cover Date.     

肺腺癌细胞微环境及转移与黏附分子表达的关系

目的研究肺腺癌细胞生长环境及转移性与黏附分子CD44v6和CD29的表达关系。方法将起源相同、转移性不同的两个肺腺癌细胞系AGZY和Anip分别用简便肿瘤多细胞球体(MTS)培养法培养，并设常规单层贴壁细胞培养对照。通过倒置显微镜、扫描及透射电镜观察MTS形成情况，并用免疫组化法分别对MTS及贴壁细胞上CD44v6和CD29表达进行检测。结果MTS培养成功，贴壁细胞与MTS在细胞结构及细胞连接结构上相似，两种MTS在形态及结构上差异无显著性。免疫组化结果显示，CD29在高转移性的Anip细胞及其MTS上呈阳性表达；在低转移性的AGZY细胞及其MTS上阴性表达。CD44v6在Anip和AGZY细胞及MTS上均呈阳性表达，差异无显著性。贴壁细胞与MTS上两种黏附分子表达均无差异。结论成功建立了一种简易制备MTS的方法。细胞生长方式(单层贴壁与MTS)可能不影响CD44v6和CD29的表达。CD29表达可能与肺腺痛转移性相关；CD44v6表达可能与肺腺癌转移无关。     

Effects of suramin on metastatic ability,proliferation, and production of urokinase-type plasminogen activator and plasminogen activator inhibitor type 2 in human renal cell carcinoma cell line SN12C-PM6

Effects of suramin, a polysulfonated naphthylurea compound, on metastatic ability, proliferation, and production of plasminogen activators and plasminogen activator inhibitors were studied using the highly metastatic human renal cell carcinoma cell line, SN12C-PM6. After renal subscapular implantation of tumor cells in nude mice, suramin significantly inhibited metastasis of tumor cells to the lungs and liver. In vitro growth of tumour cells was inhibited by suramin in a dose-dependent manner, at relatively low doses (ID₅₀ = 105 µg/ml). Plasminogen activator inhibitor type 2 (PAI-2) production by tumor cells was enhanced by suramin (100 µg/ml), whereas urokinase-type plasminogen activator (uPA) production was suppressed. Thus, the increase in PAI-2 and the decrease in uPA production correlated with the inhibitory effects on tumour growth and metastasis by suramin. Therefore suramin may be beneficial for the treatment of patients with an early stage of renal cancer with potential risk of metastasis.