Expression of CD44 variant isoforms CD44v3 and CD44v6 is increased on T cells from patients with systemic lupus erythematosus and is correlated with disease activity

Objective

To quantify the expression of CD44 and variant isoforms CD44v3 and CD44v6 on T cells from patients with systemic lupus erythematosus (SLE), and to assess correlations of the level of expression of these molecules with disease manifestations.

Methods

Information on clinical and demographic characteristics was collected, and blood samples were obtained from 72 patients with SLE and 32 healthy control subjects matched to the patients by sex, race, and age. Expression of CD44 and variants CD44v3 and v6 on T cell subsets was determined by flow cytometry, and Pearson's correlations of their expression levels with clinical variables, SLE Disease Activity Index (SLEDAI) scores, and presence of lupus nephritis were determined. Wilcoxon's rank sum tests and conditional multivariable regression analyses were applied to identify differences in the expression of CD44 between patients with SLE and healthy controls.

Results

Expression of CD44 was higher on CD4+ and CD8+ T cells from SLE patients compared with controls (P ≤ 0.03). Expression of CD44v3 and CD44v6 was also higher on total T cells and CD4+ and CD8+ T cells from SLE patients compared with controls (P ≤ 0.03). Cell surface levels of CD44v3 on total T cells, CD4+ T cells, and CD8+ T cells as well as cell surface expression of CD44v6 on total T cells and CD4+ T cells were correlated with the SLEDAI score (P < 0.05). The presence of lupus nephritis was associated with the expression of CD44v6 on total T cells, CD4+ T cells, and CD4−CD8− T cells (P < 0.05). Positivity for anti–double‐stranded DNA antibodies was associated with the expression levels of CD44v6 on T cells (P < 0.05).

Conclusion

These results indicate that expression levels of CD44v3 and CD44v6 on T cells may represent useful biomarkers of SLE activity.

     

Expression of epidermal growth factor receptor and CD44 splicing variants sharing exons 6 and 9 on gastric and esophageal carcinomas: a two-color flow-cytometric analysis

Quantitative analysis based on the percentage of positive cells by two-color flow cytometry was used to quantify the surface expression of epidermal growth factor receptor (EGFR), and exons v6 and v9 of CD44 splice variants on tumor. Almost all patients with primary gastric and esophageal carcinomas, and benign mucosa of the stomach and esophagus showed usually high levels of EGFR expression, a mean of approximately 60% of cells being positive. Metastatic gastric carcinoma showed significantly higher levels of EGFR expression, a mean of 80% of cells being positive. Reduced expression of EGFR was observed in irradiated esophageal carcinoma. Adenocarcinomas, including primary and metastatic lesions, or cancer cell lines of the stomach revealed consistently very low or undetectable levels of expression of exon v6 of the CD44 variant (CD44v) protein. However, CD44v containing exon v9 could be detected in normal gastric epithelium and primary gastric carcinoma as well as in six adenocarcinoma cell lines. Exon v9 is significantly overexpressed on metastatic adenocarcinoma cells obtained from malignant ascites. On the other hand, normal squamous epithelium and primary squamous cell carcinoma (SCC) of the esophagus, and two SCC cell lines showed coexpression of exons v6 and v9 of CD44v. The expression of the CD44v6 molecule was significantly reduced in the irradiated primary SCC, although CD44v9 expression on the primary SCC remained unchanged after the radiation therapy. These results suggest that up-regulation of EGFR and CD44v9 molecules on gastric carcinomas, especially metastatic adenocarcinomas, shows tumor growth and tumor progression. In addition, down-regulation of EGFR and CD44v6 molecules on irradiated esophageal carcinoma may be involved in the mechanisms suppressing tumor growth and metastatic potential. Received: 24 June 1998 / Accepted: 1 September 1998     

Expression and significance of CD44s, CD44v6, and nm23 mRNA in human cancer

AIM: To investigate the relationship between the expression levels of nm23 mRNA, CD44s, and CD44v6,and oncogenesis, development and metastasis of human gastric adenocarcinoma, colorectal adenocarcinoma,intraductal carcinoma of breast, and lung cancer.METHODS: Using tissue microarray by immuhistochemical (IHC) staining and in situ hybri-dization (ISH), we examined the expression levels of nm23mRNA, CD44s, and CD44v6 in 62 specimens of human gastric adenocarcinoma and 62 specimens of colorectal adenocarcinoma; the expression of CD44s and CD44v6in 120 specimens of intraductal carcinoma of breast and 20 specimens of normal breast tissue; the expression of nm23 mRNA in 72 specimens of human lung cancer and 23 specimens of normal tissue adjacent to cancer.RESULTS: The expression of nm23 mRNA in the tissues of gastric and colorectal adenocarcinoma was not significantly different from that in the normal tissues adjacent to cancer (P＞0.05), and was not associated with the invasion of tumor and the pathology grade of adenocarcinoma (P＞0.05). However, the expression of nm23 mRNA was correlated negatively to the lymph node metastasis of gastric and colorectal adenocarcinoma (r = -0.49, P＜0.01; r = -4.93, P＜0.01). The expression of CD44s in the tissues of gastric and colorectal adenocarcinoma was significantly different from that in the normal tissues adjacent to cancer (P＜0.05;P＜0.01). CD44v6 was expressed in the tissues of gastric and colorectal adenocarcinoma only, the expression of CD44v6 was significantly associated with the lymph node metastasis, invasion and pathological grade of the tumor (r = 0.47, P＜0.01; r = 5.04, P＜0.01). CD44sand CD44v6 were expressed in intraductal carcinoma of breast, the expression of CD44s and CD44v6 was significantly associated with lymph node metastases and invasion (P＜0.01). However, neither of them was expressed in the normal breast tissue. In addition, the expression of CD44v6 was closely related to the degree of cell differentiation of intraductal carcinoma of breast (x2= 5.68, P＜0.05). The expressional level of nm23mRNA was closely related to the degree of cell differentiation (P＜0.05) and lymph node metastasis (P＜0.01), but the expression of nm23 gene was not related to sex, age, and type of histological classification (P＞0.05).CONCLUSION: Patients with overexpression of CD44s and CD44v6 and low expression of nm23 mRNA have a higher lymph node metastatic rate and invasion. In addition, overexpression of CD44v6 is closely related to the degree of cell differentiation. Detection of the three genes is able to provide a reliable index to evaluate the invasion and metastasis of tumor cells.     

骨桥蛋白及 CD44 v6在肺腺癌侵袭转移中的作用

目的：探讨骨桥蛋白（ OPN）及其受体CD44v6在肺腺癌侵袭转移中的作用。方法应用免疫组化方法检测129例癌旁组织、肺原位腺癌（AIS）、伏壁样生长为主型腺癌（LPA）患者手术切除标本中OPN、CD44v6的表达情况。检测H358细胞（原位癌细胞系）和A549细胞中OPN、CD44v6蛋白及mRNA的表达,Transwell 试验观察OPN、CD44 v6对H358细胞、A549细胞侵袭力的影响。结果 OPN、CD44 v6在LPA组织中的表达阳性率显著高于AIS及癌旁组织,AIS高于癌旁组织,OPN与CD44v6的表达呈显著正相关（ P＜0．05）。 OPN、CD44v6及OPN mR-NA、CD44v6 mRNA在A549细胞中的表达水平高于H358细胞。 Transwell试验提示OPN对A549细胞的趋化作用高于H358细胞。使用OPN抗体阻断OPN对两种细胞的趋化作用,两种细胞穿过数均减少;阻断CD44 v6受体通道后,OPN对两种细胞的趋化作用明显减弱。结论 OPN-CD44 v6复合体对肺腺癌的侵袭能力具有重要作用,OPN有望成为评估肺腺癌进展及预测肿瘤转移潜能的指标。     

Endothelial adhesion of synchronized gastric tumor cells changes during cell cycle transit and correlates with the expression level of CD44 splice variants

AIM: To study adhesion capacity and CD44 expression of human gastric adenocarcinoma MKN45 cells at different stages of a first cell cycle. METHODS: MKN45 cells were synchronized by aphidicolin and assayed for adhesion to an endothelial cell (HUVEC) monolayer. Surface expression of CD44 and CD44 splice variants on MKN45 cells was evaluated by flow cytometry. Functional relevance of CD44 adhesion receptors was investigated by blocking studies using anti CD44 monoclonal antibodies or by hyaluronan digestion. RESULTS: Adhesion of MKN45 to HUVEC was increased during G2/M transit, after which adhesion returned to baseline levels with cell cycle completion. In parallel, CD44 splice variants CD44v4, CD44v5, and CD44v7 were all up-regulated on MKN45 during cell cycle progression with a maximum effect in G2/M. The function of CD44 surface receptors was assessed with specific receptor blocking monoclonal antibodies or removal of hyaluronan by digestion with hyaluronidase. Both strategies inhibited tumor cell adhesion to HUVEC by nearly 50%, which indicates that MKN45-HUVEC-interaction is CD44 dependent. CONCLUSION: CD44 expression level is linked to the cell cycle in gastrointestinal tumor cells, which in turn leads to cell cycle dependent alterations of their adhesion behaviour to endothelium.     

Endothelial adhesion of synchronized gastric tumor cells changes during cell cycle transit and correlates with the expression level of CD44 splice variants

AIM: To study adhesion capacity and CD44 expression of human gastric adenocarcinoma MKN45 cells at different stages of a first cell cycle.METHODS: MKN45 cells were synchronized by aphidicolin and assayed for adhesion to an endothelial cell (HUVEC)monolayer. Surface expression of CD44 and CD44 splice variants on MKN45 cells was evaluated by flow cytometry.Functional relevance of CD44 adhesion receptors was investigated by blocking studies using anti CD44 monoclonal antibodies or by hyaluronan digestion.RESULTS: Adhesion of MKN45 to HUVEC was increased during G2/M transit, after which adhesion returned to baseline levels with cell cycle completion. In parallel, CD44splice variants CD44v4, CD44v5, and CD44v7 were all upregulated on MKN45 during cell cycle progression with a maximum effect in G2/M. The function of CD44 surface receptors was assessed with specific receptor blocking monodonal antibodies or removal of hyaluronan by digestion with hyaluronidase. Both strategies inhibited tumor cell adhesion to HUVEC by nearly 50%, which indicates that MKN45-HUVEC-interaction is CD44 dependent.CONCLUSION: CD44 expression level is linked to the cell cycle in gastrointestinal tumor cells, which in turn leads to cell cyde dependent alterations of their adhesion behaviour to endothelium.     

Expression of CD44 variants in osteosarcoma

The standard form of CD44 (CD44H) is a transmembranous glycoprotein, widely distributed on a variety of human lymphoid cells, epithelial cells and tumours. CD44 has many variant forms, which are generated by alternative splicing. In recent years, CD44 has been reported to be related to the degree of tumour differentiation, tumour cell invasion, and metastasis. We investigated 44 tumour specimens in 39 patients with osteosarcoma immunochemically to analyse the expression of CD44 standard (CD44H) and variant exon-encoded gene products (CD44v3, v4, v5, v6, v7, v9, and v10). Furthermore, the relationship between CD44 expression and the clinical outcome of patients with osteosarcoma was analysed. Membrane accentuation and exclusive cytoplasmic reactivity were analysed as separate staining patterns. Tumour cells and some multinucleated giant cells were markedly stained. CD44H, v3, v4, v5, v6, v7, v9, and v10 were expressed in 85%, 49%, 54%, 59%, 46%, 5%, 28%, and 10% of the specimens respectively. The cumulative 5-year metastasis-free survival was 58% in CD44v6-negative cases and 24% in CD44v6-positive cases (P=0.046). However, the cumulative 5-year metastasis-free survival was not significantly different between cases positive and negative for other variants of CD44. Multivariate analysis (Cox proportional-hazard model) with CD44v6 expression (positive or negative), chemotherapy (intensive or non-intensive), tumour site (proximal or distal), and age (at least 30 years or less than 30 years) showed that expression of CD44v6 and chemotherapy were important prognostic factors in patients with osteosarcoma. Overexpression of CD44 isoforms containing variant v6 is correlated with poor prognosis in patients with osteosarcoma. Received: 4 March 1999 / Accepted: 7 June 1999     

原发性肝细胞癌中CD44v6和nm23H1基因的转录表达及临床意义

研究CD44v6 mRNA和nm23H1 mRNA表达与肝细胞癌（HCC）侵袭转移和预后的关系。应用原位杂交方法，检测分析HCC组织中CD44v6 mRNA和nm23H mRNA表达。99例HCC中，CD44v6 mRNA和nm23H1 mRNA表达阳性率分别为41．4％和76．8％。CD44v6mRNA表达与nm23H1mRNA表达呈负相关。CD44v6和nm23HmRNA表达均与HCC侵袭转移倾向和预后相关。检测CD44v6和nm23H1表达有可能成为HCC 侵袭转移和预后判断的病理生物学指标。     

Levels of v5 and v6 CD44 splice variants in serum of patients with colorectal cancer are not correlated with pT stage，histopathological grade of malignancy and clinical features

AIM: This study was designed to compare the levels of v5 and v6 splice variants of CD44 evaluated using ELISA test in the serum of patients with colorectal cancer in different stages of progression of the disease estimated in pT stage according to WHO score, histopathological grade of malignancy and some clinicopathological features. METHODS: The serum obtained from 114 persons with colorectal adenocarcinomas was examined using ELISA method. pT stage and grade of malignancy of the tumour were examined in formalin fixed and paraffin embedded materials obtained during operation. RESULTS: Only the level of CD44 v5 in the serum of patients before operation with G2 pT4 tumour was lower than that in other probes and the difference was statistically significant. We did not find any other correlations between the level of v5 and v6 CD44 variants and other evaluated parameters. CONCLUSION: The level of CD44 v5 and v6 estimated by ELISA test in the serum can not be used as a prognostic factor in colorectal cancer.     

CD44 Splice Variants as Prognostic Markers in Colorectal Cancer

Background: Splice variants of CD44 play a causal role in the metastatic spread of pancreatic carcinoma in the rat. In previous studies we have shown that homologues of these CD44 isoforms (CD44v6) are overexpressed during colorectal tumorigenesis in man and that CD44v6 overexpression is associated with an unfavorable prognosis in this disease. In the present study we have assessed the prognostic significance of CD44 variants containing exon v5. In addition, we have used a panel of different antibodies against CD44v6 and applied a combined scoring system to improve its value as prognosticator. Methods: Expression of CD44 variants was studied by immunohistochemistry on frozen tissue sections, and the prognostic value of the CD44 variant expression was assessed using univariate and multivariate analysis. Results: Our studies show that expression of CD44v6, but not CD44v5, has significant prognostic value. Analysis of CD44v6 expression by means of a combined scoring system, on the basis of a panel of three different monoclonal antibodies (mAbs), makes CD44v6 a highly significant prognostic marker that is independent of Dukes stage, tumor grade, or tumor localization. Conclusion: Assessment of CD44v6 expression by a combination of mAbs yields an independent prognosticator that may be of value in identifying patients with a high propensity to develop distant metastasis.     

CD44v6和MMP-9在胎盘原位滋养细胞肿瘤中的表达及相关性

目的探讨CD44v6和基质金属酶-9（MMP-9）在胎盘原位滋养细胞肿瘤（PSTT）中的表达及相关性。方法采用SABC免疫组化法检测30例正常绒毛、15例PSTT的CD44v6和MMP-9表达情况。结果CD44v6在正常胎盘绒毛、良性PSTT、恶性PSTT的阳性表达率分别是3．3％、30．3％、100％,组间比较差异有统计学意义（P〈0．05）;而MMP-9的阳性表达率分别为6．7％、38．5％、100％,组间比较差异有统计学意义（P〈0．05）。结论CD44v6和MMP-9的过表达促进PSTT的浸润转移,二者具有正协同作用,联合检测CD44v6和MMP-9蛋白可作为PSTT的浸润转移及评价预后生物学指标。     

胆囊癌组织中CD44v6和nm23的表达及其意义

目的研究胆囊癌组织中CD44v6、nm23蛋白表达及意义和两者之间的关系。方法用免疫组化的方法检测 36例胆囊癌和27例癌旁上皮组织中CD44v6和nm23蛋白的表达。结果胆囊癌组织中CD44v6和nm23的阳性率分别为41.7％和72.2％,均与癌旁上皮的阳性率有显著性差异:CD44v6的表达与胆囊癌的淋巴结转移呈正相关,而与组织学类型、临床分期无关;nm23的表达与胆囊癌的淋巴结转移、临床分期呈负相关,而与组织学类型无关。CD44v6和nm23蛋白的表达呈负相关。结论 CD44v6和nm23蛋白可能在胆囊癌的形成、淋巴结转移和病程进展等方面起着重要作用,且两者呈互相拮抗的关系,可作为判断胆囊癌侵袭和淋巴结转移的标记物。     

VEGF和CD44v6过表达与乳腺癌浸润转移的关系

目的检测血管内皮生长因子(VEGF)和转移相关黏附分子44v6(CD44v6)在乳腺癌中的表达情况,探讨两者与淋巴结转移的关系。方法采用免疫组化SP法检测92例乳腺浸润性癌中VEGF、CD44v6的表达情况。结果 VEGF在正常乳腺组织和乳腺癌中的阳性表达率分别为6.7%(3/45)和90.2%(83/92),且VEGF在淋巴结转移组中的阳性表达率(53/55)明显高于无淋巴结转移组(P<0.05)。CD44v6在正常乳腺组织及乳腺癌中的阳性表达率分别为8.9%(4/45)和85.9%(79/92),而且CD44v6在淋巴结转移组中的阳性表达率(51/55)明显高于无淋巴结转移组(P<0.05)。VEGF和CD44v6表达呈正相关关系(r=0.497,P<0.05)。结论 VEGF、CD44v6在乳腺癌组织中高表达,且均与淋巴结转移有关(P<0.05),两者可能在乳腺癌的远处转移中起协同作用。     

明胶酶、CD44v6在结直肠癌中的表达及意义

目的探讨明胶酶在结直肠癌中的表达及其CD44v6在结直肠癌侵袭转移过程中的关系。方法采用明胶酶谱（gel zymography）和S-P免疫组化对50例结直肠癌癌组织和相应正常组织中的明胶酶、CD44v6进行检测。结果明胶酶在结直肠癌中的表达水平显著高于正常组织（P〈0．05）；明胶酶与结直肠癌的Duke’s分期呈同步的正相关（P〈0．05）；明胶酶在CD44v6强阳性组中表达量升高显著（P〈0．05）。结论明胶酶与结直肠癌的侵袭转移性有着密切的关系，不仅在癌细胞的酶解，而且在癌细胞的黏附、运动过程中有可能发挥着重要作用。