The MHC class-II and CD44 molecules are involved in the induction of tumour necrosis factor (TNF) gene expression by human monocytes stimulated with tumour cells

Tumour necrosis factor alpha (TNF) mRNA is detected in the macrophage infiltrate surrounding the tumour, but the cellular/ molecular interactions leading to TNF gene expression in macrophages are unknown. The in vitro system in which human blood monocytes are stimulated with human cancer cells for TNF release was used to study such interactions. Monoclonal antibodies (MAbs) against various adhesion molecules (LFA-I, LFA-3, (CAM-I, VNR, VLAβI chain) were unable to block TNF production in co-culture of monocytes with a human pancreatic carcinoma (HPC) cell line. However, anti-CD44 and anti-HLA-DR MAbs effectively blocked TNF release and TNF-mRNA induction in monocytes. Pre-incubation of monocytes with anti-HLA-DR and tumour cells with anti-CD44 MAbs had a similar effect. It was concluded that CD44 molecules are involved in tumour-monocyte interactions and that HLA-DR determinants of monocytes are engaged in signal transduction for TNF gene activation. These findings may suggest that certain surface determinants of tumour cells act as ligands for MHC class-II molecules and induce TNF production in monocytes.     

Involvement of pattern recognition receptors in the induction of cytokines and reactive oxygen intermediates production by human monocytes/macrophages stimulated with tumour cells

BACKGROUND: Some ligands of pattern recognition receptors (PRR) are present on tumour cells. The role of PRR in signalling for cytokine and reactive oxygen intermediates (ROI) production by monocytes and monocyte-derived macrophages (MDM) stimulated with tumour cells was studied. MATERIALS AND METHODS: Monocytes/MDM were pretreated with PRR ligands or anti-PRR monoclonal antibodies (mAbs) and stimulated with tumour cells. Cytokine secretion was measured by enzyme-linked immunoassay (ELISA) and ROI production by luminol-dependent chemiluminescence (CL). RESULTS: The ligands of scavenger receptor A (SR-A): (fucoidan, polyguanylic acid (polyG) and modified low density lipoproteins (LDL)) and B (SR-B) (native and modified LDL, phosphatidylserine (PdS)) and of mannose receptor (MR) (mannan), induced tumour necrosis factor alpha (TNF) and ROI (except LDL) release by monocytes. Production of TNF and interleukin-10 (IL-10) by MDM was stimulated by SR-A ligands and mannan. Tumour cell-induced TNF and IL-10 production by monocytes, but not MDM, was diminished by fucoidan and polyG, while ROI release was reduced by MR and SR-A ligands. Supplementation of tumour cells with modified LDL and PdS enhanced their stimulatory capacity. TNF and ROI release by tumour cells-stimulated monocytes was inhibited by anti-CD36 and anti-MR (clone PAM-1) mAbs. CONCLUSION: SR and MR may be involved to different extents in the induction of cytokines and ROI production by monocytes, but not MDM, stimulated with tumour cells.     

Characterisation of tumour-infiltrating macrophages: impact on response and survival in patients receiving primary chemotherapy for breast cancer

The role of the tumour microenvironment and complex cellular interactions has attracted interest in responses to primary chemotherapy. Of particular interest are tumour-infiltrating T cells and tumour-infiltrating macrophages (TIMs). We evaluated TIMs and their key activation markers in patients with breast cancer undergoing primary chemotherapy related to response and survival. One hundred and ninety nine patients with large or locally advanced breast cancers received primary chemotherapy. Clinical data, histopathological responses to chemotherapy and survival were examined related to infiltrating cells in tumour microenvironments: cluster of differentiation (CD)3 (pan T cell); CD4 (helper T cells); CD8 (cytotoxic T cells); CD25 (activated T cells); CD68, suppressor of cytokine signalling (SOCS)1, SOCS3 (macrophages); and CD11c and CD205 (dendritic). In tumours demonstrating better responses to chemotherapy, there were significantly fewer CD4(+) T-helper cells than a poorer response (p?相似文献   

N-acetyl-L-cysteine suppresses constitutive expression of CD11a/LFA-1alpha protein in myeloid lineage

We investigated the possible involvement of redox regulation in constitutive expression of CD11a/LFA-1alpha, a leukocyte integrin alpha subunit, in myeloid cells using antioxidants. In unstimulated HL-60 cells, CD11a/LFA-1alpha was highly expressed, however, no expression of CD11b and CD11c proteins was detected. N-acetyl-L-cysteine (NAC) markedly down-regulated CD11a/LFA-1alpha expression in a dose-dependent manner. The down-regulated CD11a/LFA-1alpha expression was gradually recovered when NAC was deprived 24h after treatment. Pyrrolidine dithiocarbamate (PDTC) also suppressed the level of expression CD11a/LFA-1alpha protein, although the effect of PDTC was less potent than NAC. Both NAC and PDTC suppressed NF-kappaB binding activity to consensus DNA probe, and this result was correlated with a suppressive effect to CD11a/LFA-1alpha expression. Furthermore, NAC also down-regulated CD11a/LFA-1alpha expression in both U937 cells and peripheral blood monocytes. These results indicated that the constitutive CD11a/LFA-1alpha expression in the myeloid lineage is implicated in oxidative stress occurring spontaneously, suggesting that alteration of the intracellular redox state using antioxidants may be effective in the modulation of cell adhesion associated with extravasation in leukocytes, at least, in myeloid cells.     

Crosstalk between colon cancer cells and macrophages via inflammatory mediators and CD47 promotes tumour cell migration

Tumour-associated macrophages (TAMs) of the M2 phenotype are present in the stroma of many tumours and are frequently associated with the progression of several types of cancer. We investigated the role of M2 macrophages in colon cancer progression and found that human colon cancer tissue had elevated numbers of CD68⁺ (macrophage marker) cells and CD206⁺ (M2 macrophage marker) cells and increased CD47 expression. To explore potential interplay between colon cancer cells and M2 macrophages, we differentiated the monocyte cell line THP-1 into M1 and M2 macrophages (CD206^high and Th2 cytokine-secreting cells), respectively. M2 macrophages migrated faster than M1 macrophages towards SW480-conditioned medium. Similarly, M2 macrophage-conditioned medium induced SW480 cell migration and CD47 expression. Factors released by macrophages were involved in this induction. In addition, SW480 cells migrated faster when co-cultured with M2 macrophages. Inhibition of CD47 with blocking antibodies or siRNA significantly reduced the migration of SW480 cells in the presence of M2 macrophages. This effect was further decreased via blocking antibodies against the CD47 ligand signal-regulatory protein α (SIRPα). Additionally, cancer cells also secreted significant levels of IL-10, thereby promoting M2 macrophage differentiation. These findings indicate that a TAM-enriched tumour microenvironment promotes colon cancer cell migration and metastasis.     

Defective antigen presentation resulting from impaired expression of costimulatory molecules in breast cancer

Previous experiments from our laboratory have shown that immune mechanisms aiming at the destruction of tumour cells including the recognition of target cells and their elimination via the expression of intercellular adhesion molecule-1 (ICAM-1; CD54), the production of tumour necrosis factor-alpha (TNF-alpha) by monocytes and appropriate function of lymphocyte subpopulations were defective in breast cancer. Previous observations were extended to assess expression levels and regulatory mechanisms of costimulatory molecules CD54, CD80 and CD86 on monocytes derived from patients with early breast cancer (EBC). In addition, antigen presentation by antigen-presenting cells (APC) was analyzed within this context. We report that monocytes derived from patients with EBC exhibited significantly decreased expression levels of CD54 (p = 0.0002), CD80 (p = 0.009) and CD 86 (p = 0.002) compared with monocytes derived from healthy females. Simultaneously, lipopolysaccharide (LPS)-induced TNF-alpha production of monocytes was found to be defective in patients with EBC. Finally, T-cell proliferation in response to tetanus toxoid (TT) was significantly decreased in patients with EBC compared with healthy control females (p < 0.0001). Furthermore, T-cell proliferation in response to TT-pulsed APC derived from healthy controls was significantly inhibited in the presence of anti-CD54 and/or anti-CD80 antibodies in a dose-dependent manner, thus corroborating the necessity of the presence of CD54 and CD80 as costimulatory molecules in the present setting. We conclude that monocytes derived from patients with EBC showed a simultaneous defect of expression of CD54 and its regulation via TNF-alpha, CD80 and CD86 as well as T-cell proliferation following exposure to TT-pulsed APC. Based upon these findings, it is speculated that defects in costimulatory molecule expression might contribute to tolerance of the immune system towards the presence of malignant cells in patients with EBC.     

CD44 stimulation induces integrin-mediated adhesion of colon cancer cell lines to endothelial cells by up-regulation of integrins and c-Met and activation of integrins.

For cancer metastasis, tumor cells present in the circulation must first adhere to the endothelium. Integrins lymphocyte function-associated antigen (LFA) 1 and very late antigen 4 play a central role in leukocyte adhesion to the endothelium and subsequent migration into tissues. The majority of tumor cells derived from solid cancers including colorectal cancer do not express suitable adhesion receptors, LFA-1 and very late antigen 4. We investigated the mechanisms of adhesion and transendothelial migration of cancer cells using colorectal carcinoma cell lines. Our results showed the following novel features of CD44 on the cells: (a) colon cancer cells express high levels of CD44; (b) stimulation of cancer cells by CD44 cross-linking or fragmented hyaluronan markedly induces the expression of LFA-1s, some of which reveal an activation epitope on the cells; (c) CD44 cross-linking induces F-actin polymerization in the cell cortex; (d) fragmented hyaluronan induces up-regulation of the activation epitope of LFA-1, which is mediated through protein kinase C; (e) stimulation of CD44 augments the LFA-1-mediated adhesion of cancer cells to endothelial cells and intercellular adhesion molecule 1-transfected cells and facilitates transendothelial migration; (f) stimulation of CD44 also induces expression of the hepatocyte growth factor (HGF) receptor c-Met on cancer cells; and (g) HGF further amplifies the LFA-1-mediated adhesion of cells prestimulated by CD44-derived signaling. Our results indicated that stimulation by CD44 induces "outside-in signaling," which consists of a direct pathway via CD44 and an alternate pathway through the induction of c-Met expression via HGF. Such stimuli augment the expression and trigger the function of integrins via "inside-out signaling" in colon cancer cells, which leads to amplification of integrin-mediated adhesion to the vessel wall and subsequent transendothelial migration.     

Cross-talk between human monocytes and cancer cells during reactive oxygen intermediates generation: the essential role of hyaluronan.

Human monocytes exhibit considerable cytocidal activity against tumor (but not normal cells) associated, at least partly, with the generation of reactive oxygen intermediates (ROIs). The present study examined the role of surface determinants and hyaluronan (HA) in the induction of ROI production by human monocytes stimulated with cancer cells, as measured by luminol-enhanced chemiluminescence (CL). The inhibitory effect of monoclonal antibodies (MAbs) indicated the engagement of CD18, CD29 and CD44 adhesion molecules. Preincubation of monocytes and tumor cells, expressing CD44 determinants, with either anti-CD44 MAb or HA inhibited CL generation. Addition of HA to monocytes decreased the expression of CD44 and induced CL response. Supernatants from the cultures of tumor cells stimulated CL response of monocytes, an effect that was abolished by treatment of the supernatants with hyaluronidase (HAase) or by preincubation of monocytes with an anti-CD44 MAb. These results indicate that several surface molecules of monocytes, including CD44, are required to trigger the generation of ROI after their contact with tumor cells, whereas HA overexpressed on some cancer cells may allow monocytes (via CD44) to distinguish between transformed and normal cells. However, blocking of CD44 on monocytes by free HA dampens their response to tumor cells. Taken together, these observations suggest that the presence of HA in the tumor stroma may modulate effector functions of infiltrating macrophages and their interactions with cancer cells in situ.     

TX-1877, a bifunctional hypoxic cell radiosensitizer, enhances anticancer host response: immune cell migration and nitric oxide production

We investigated in the current study the effect of TX-1877, a bifunctional hypoxic cell radiosensitizer, in augmenting anticancer host response. In the syngeneic squamous cell carcinoma-bearing mouse model, a single administration of TX-1877 significantly inhibited the primary tumor growth as well as lung metastasis. TX-1877 administration resulted in a significant infiltration of immune cells, such as CD4+T, CD8+T cells, macrophages and dendritic cells (DCs), and an increased expression of chemokines for cytotoxic T lymphocytes (CTLs), helper T-cell 1 (Th1) cells, monocytes/macrophages and DCs, in tumor tissues. Nitric oxide (NO) production and the expression of inducible NO synthase (iNOS) and interferon-gamma, a major Th1 cytokine that plays a major role in anticancer immunity, were also enhanced. Furthermore, neutralization of NO by N-monomethyl-L-arginine acetate resulted in a marked inhibition of the antitumor effect of TX-1877. In tumor-draining lymph nodes, MHC class I-restricted CD8+ memory CTLs specific for inoculated cancer cells were induced by TX-1877. In in vitro experiments, TX-1877 induced chemokines and iNOS/NO in several types of culture cells. These findings strongly suggested that TX-1877 induces migration of CD8+CTLs, CD4+Th1 cells, macrophage/monocytes and dendritic cells into the tumor site, and that this migration is mediated by chemokine induction. In addition, it was suggested that NO produced by several types of cells stimulated by TX-1877 in the tumor sites plays a major role in the anticancer effect of TX-1877. TX-1877 was thus shown to be an effective immunopotentiator as well as a hypoxic cell radiosensitizer.     

Expression of the leucocyte integrin LFA-1 (CD11a/CD18) and its ligand ICAM-1 (CD54) in lymphoid malignancies is related to lineage derivation and stage of differentiation but not to tumor grade.

The leucocyte adhesion molecule LFA-1 (CD11a/CD18) and its counter structure ICAM-1 (CD54) play a pivotal role in cell-cell interactions in the immune system and hence their expression on malignant cells might play an important role in determining the biological behavior of lymphoid malignancies. This study examined the LFA-1 (CD11a/CD18) and ICAM-1 (CD54) expression profiles of a large series of non-Hodgkin's lymphomas (NHL, n = 220) and lymphoid leukemias (LL, n = 48), which, by their differentiation-antigen phenotype represented essentially all stages of lymphoid development from stem cell to mature activated T- and B-lymphocyte. It was found that NHL and LL differentially express LFA-1 and ICAM-1 molecules according to their lineage derivation, stage of differentiation, and growth pattern. Specifically: (a) T-cell neoplasms nearly always express LFA-1 whereas B-cell tumors are often LFA-1 low/negative; (b) ICAM-1 expression is largely confined to tumors with a mature or activated T- or B-cell phenotype; (c) neoplasms with a leukemic dissemination pattern are either ICAM-1 low or negative. Importantly, neither LFA-1 nor ICAM-1 expression was related to tumor grade.     

Ionizing radiation induces macrophage foam cell formation and aggregation through JNK-dependent activation of CD36 scavenger receptors

PURPOSE: Irradiated arteries of cancer patients can be associated with atherosclerosis-like lesions containing cholesterol-laden macrophages (foam cells). Endothelial cell damage by irradiation does not completely explain the foam cell formation. We investigated the possible underlying mechanisms for ionizing radiation (IR)-induced foam cell formation. METHODS AND MATERIALS: Human peripheral blood monocytes were activated by macrophage colony-stimulating factor and then treated with varying doses of IR in vitro in the absence of endothelial cells. Scavenger receptor expression and foam cell formation of IR-treated macrophages were investigated in the presence or absence of oxidized low-density lipoprotein. We also assessed the importance of mitogen-activated protein kinase activity in the macrophage colony-stimulating factor-activated human monocytes (macrophages) for the foam cell formation. RESULTS: We found that IR treatment of macrophage colony-stimulating factor-activated human peripheral blood monocytes resulted in the enhanced expression of CD36 scavenger receptors and that cholesterol accumulated in the irradiated macrophages with resultant foam cell formation in the presence of oxidized low-density lipoprotein. Furthermore, when cultured on collagen gels, human macrophages formed large foam cell aggregates in response to IR. Antibodies against CD36 inhibited the IR-induced foam cell formation and aggregation, indicating that the IR-induced foam cell formation and the subsequent aggregation are dependent on functional CD36. In addition, we found that IR of human macrophages resulted in c-Jun N-terminal kinase activation and that c-Jun N-terminal kinase inhibition suppressed IR-induced CD36 expression and the subsequent foam cell formation and aggregation. CONCLUSION: Taken together, these results suggest that IR-induced foam cell formation is mediated by c-Jun N-terminal kinase-dependent CD36 activation.     

Bladder cancer cells do not express co-stimulatory molecules B7-1, B7-2 and B7-3

It is widely established that BCG is an effective treatment for transitional cell carcinoma (TCC). Its clinical benefit might be attributable to effects both on immuno-competent cells themselves and the tumour, e.g., the induction of MHC Class II and ICAM-1 expression which are known to facilitate effector cell/ target cell interactions. It is of interest that the success of this therapy might be due in part to the induction of B7 molecules which could provide vital co-stimulatory signals to the host immune system. We showed that a panel of 8 TCC cell lines failed to express B7-1,-2,-3 molecules constitutively or after stimulation. Bladder cancer cells shed following immunotherapy also failed to express B7. After therapy B7 expression, however, was found on cells of lymphocytic and monocytic lineage produced locally. Of other co-stimulatory molecules examined (ICAM-3, HSP72, CD1b, VCAM) only CD40 appeared to be expressed on some of TCC cell lines. All cell lines failed to express previously predicted ICAM-3 indicating a possible existence of a novel ligand for LFA-1.     

The prognostic value of CD44 isoform expression in endometrial cancer.

Isoforms of the transmembrane glycoprotein CD44 have been implicated in tumour cell adhesion, tumour differentiation and metastatic spread in various human malignancies. We investigated the expression of CD44 isoforms containing variant exons v3, v5, v6 and v7-8 in 156 human endometrium cancer specimens by means of immunohistochemistry. CD44 isoforms CD44v3, CD44v5, CD44v6 and CD44v7-8 were detected in 26% (41 out of 156), 31% (48 out of 156), 22% (35 out of 156) and 15% (23 out of 156) of the tumour samples respectively. The expression of CD44 isoforms CD44v3, CD44v5 and CD44v7-8 showed no prognostic impact. In the univariate analysis, the expression of CD44v6 showed an association with shortened overall survival (log-rank test, P = 0.06). Multivariate analysis correcting for the confounding variable histological grading revealed CD44v6 not to be a prognostic factor in endometrial cancer (log-rank test, P = 0.06). Comparing the expression of CD44 isoforms CD44v3, CD44v5, CD44v6 and CD44v7-8 in 45 specimens of normal endometrial tissue, we found an up-regulation of all investigated CD44 isoforms in the secretory phase compared with the proliferative phase of the menstrual cycle. Our data indicate that the expression of CD44 isoforms, while obviously playing a role in the functional changes of normal endometrium, is not an adverse predictive factor in endometrial cancer.     

Expression of adhesion molecules in B-cell chronic lymphocytic leukaemia: an analysis in lymphoid compartments--peripheral blood, bone marrow and lymph node

The trafficking or homing of different lymphoid subsets to particular microenvironment is mediated by specific cell adhesion molecules (CAMs) expressed on lymphocytes and endothelial cells. B-cell chronic lymphocytic leukaemia (B-CLL) or Non-Hodgkin's lymphoma of small lymphocytic, B-cell type are monoclonal expansions of mature lymphocytes. The relative distribution of the tumor lymphocytes among various lymphoid compartments vary from patient to patient. Very few studies underlying this issue are available. To this effect, we have analysed the expression of LFA-1; VLA-4, ICAM-1; CD44H and CD44v6 (haematopoietic and variant form respectively) on freshly isolated lymphocytes obtained from bone marrow (BM), peripheral blood (PB) and lymph node (LN) by flow cytometry. Overall, we find strong expression of CD44H, low to moderate expression of LFA-1, negative to low expression of VLA-4 and lack of expression of CD44v6. ICAM-1 expression was observed only in patients with prominent lymphadenopathy. Higher expression of CD44H in PB lymphoid cells relative to that of BM lymphoid cells correlated with higher PB lymphocytosis (p < 0.001). Proliferating cell nuclear antigen expression in LN sections correlated inversely with VLA-4 expression on BM and PB lymphoid cells (p < 0.05). There was no significant correlation between expression of CAMs and bcl-2 protein.     

Flow cytometric investigation of immune-response-related surface molecules on human colorectal cancers

Our purpose was to clarify whether human colorectal cancer cells are equipped to present tumour-associated-antigens to the immune system, and whether this ability correlates with lymphoid infiltration, the Dukes' stage and Jass classification. Enzymatically dissociated tumour cells from 70 different colorectal cancers were monitored by multiparameter flow cytometry. Gating on EP4⁺ cells, the expression of the surface molecules HLA class I, HLA class II, CD80 (B7-1), CD54 (ICAM-1) and CD58 (LFA-3) was evaluated. In 60 of 70 tumours, all tumour cells expressed HLA class I, in 10 tumours 15-96% of the tumour cells expressed HLA class I. In 1 tumour, all tumour cells expressed HLA class II, in 67 tumours some expressed HLA class II, in 2 tumours none expressed HLA class II. Expression of CD58 was heterogeneous, and there was no or only sparse expression of CD80 and CD54. Expression of the HLA class I molecules, but not the class II, was correlated with lymphoid infiltration and the Jass classification. Expression of these surface molecules was not correlated with the Dukes' stage. The tumour cells were generally equipped to present antigens to the effector arm of the immune system since HLA class I is expressed, but the tumour cells were not optimal in stimulating an immune response, since HLA class II and CD58 were only marginally expressed and CD80 and CD54 were absent. Int. J. Cancer (Pred. Oncol.) 79:283–287, 1998.© 1998 Wiley-Liss, Inc.     

T-cell lymphomas mask slower developing B-lymphoid and myeloid tumours in transgenic mice with broad haemopoietic expression of MYC

Deregulation of MYC expression occurs in many haematological malignancies. Previous studies modelling MYC-induced lymphomagenesis in the mouse used transgenic vectors that directed MYC overexpression in a lineage-specific manner. Here, we describe a transgenic mouse strain in which constitutive MYC expression is driven broadly in haemopoiesis by a vector containing regulatory elements of the Vav gene. Healthy young VavP-MYC17 mice had multiple haemopoietic abnormalities, most notably increased size and numbers of B-lymphoid cells, monocytes and megakaryocytes. The mice rapidly developed tumours and, surprisingly, these were exclusively T-cell lymphomas, mostly of mature CD4(+) CD8(-) T cells, a tumour type that is seldom seen in mouse models. To examine tumour development in the absence of the susceptible T cells, we bred VavP-MYC17 mice lacking the Rag1 recombinase. They survived longer and succumbed to tumours of several different haemopoietic cell types: pre-T cells, pro-B cells, macrophages and unusual progenitor cells. Thus, although T-lineage cells have the shortest latent period to transformation, the VavP-MYC17 transgene drives malignant transformation of multiple cell types and VavP-MYC17 mice provide a new model for tumours of multiple haemopoietic lineages.     

三阴性乳腺癌细胞源性外泌体活化的巨噬细胞促进乳腺癌细胞的迁移和侵袭

目的:研究三阴性乳腺癌（triple-negative breast cancer,TNBC）细胞来源的外泌体对巨噬细胞极化作用以及经外泌体活化的巨噬细胞对TNBC细胞迁移和侵袭能力的影响及作用机制。方法:提取TNBC细胞BT-549和MDA-MB-231外泌体,透射电镜、纳米颗粒跟踪分析（nanoparticle tracking analysis,NTA）、蛋白质印记(Western blot)鉴定外泌体;流式细胞术检测经外泌体处理后巨噬细胞分子标志物CD206、CD80的表达;实时荧光定量PCR检测单核细胞THP-1、巨噬细胞M0及外泌体处理后巨噬细胞中CD163、转化生长因子β(transforming growth factor β,TGF-β)、一氧化氮合酶(nitric oxide synthase,iNOS)、肿瘤坏死因子α(tumor necrosis factor α,TNF-α)的mRNA水平;Transwell实验分析外泌体活化的巨噬细胞对TNBC细胞迁移和侵袭的影响,Western blot方法检测MMP-2、MMP-9、N-cadherin、E-cadherin的蛋白水平。结果:透射电镜下BT-549和MDA-MB-231细胞的外泌体具有膜结构囊状小泡并表达外泌体的分子标记物CD81、CD63;BT-549细胞来源的外泌体直径分布为80~150 nm,MDA-MB-231细胞来源的外泌体直径分布为100~200 nm;经BT-549和MDA-MB-231细胞源性外泌体处理的巨噬细胞与M0相比,CD206均有稳定表达（P＜0.05),而CD80表达未见明显差异;外泌体处理后巨噬细胞的CD163、TGF-β mRNA表达水平均增加（P＜0.01),iNOS mRNA表达水平降低（P＜0.05),TNF-α mRNA表达水平未见明显变化;外泌体处理后的巨噬细胞使得TNBC细胞的迁移、侵袭穿膜数目增加(P＜0.01),N-cadherin、MMP-2和MMP-9蛋白表达增加（P＜0.05),E-cadherin 蛋白表达降低（P＜0.05)。结论:TNBC细胞分泌的外泌体可以诱导巨噬细胞向M2极化,进而促进TNBC细胞间质转化,增强TNBC细胞的迁移和侵袭能力。     

Immunohistochemical and serological evaluation of CD44 splice variants in human ovarian cancer.

The surface glycoprotein CD44 is widely distributed in different tissues. In contrast to healthy tissue, tumour samples show a more complex pattern of CD44 expression, indicating a loss of splice control. Beside cell-surface expression, the measurement of soluble CD44 in serum of cancer patients could be useful in early diagnosis and assessment of disease status. We evaluated the surface expression of CD44 isoforms in 22 ovarian cancer patients by means of immunohistochemistry. Additionally, we investigated 134 serological samples of these patients for the occurrence of CD44 isoform expression. For CD44 standard, CD44v5 and CF44v6 mean serum levels in patients with clinically detectable or non-detectable ovarian cancer were 422.4 +/- 143.8 ng ml-1 and 547.4 +/- 148.2 ng ml-1, 12.3 +/- 7.9 ng ml-1 and 21.9 +/- 12.2 ng ml-1 and 105.5 +/- 37.9 ng ml-1 and 144.9 +/- 50.9 ng ml-1 respectively (P-values not significant). CD44 surface proteins containing epitopes encoded by splice variants CD44v5, CD44v6 and CD44v7-8 were immunohistochemically detected in 9% (n = 2), 13% (n = 3) and 4% (n = 1) of the 22 tumour samples respectively. In the present study we showed that in ovarian cancer CD44 isoforms CD44v5 and CD44v6 are expressed in very low amounts by the tumours. In accordance with this, we found that the presence of tumour is not associated with higher serum levels of CD44standard, CD44v5 and CD44v6 in preoperative serum samples in ovarian cancer patients.