Comparison between interphase and metaphase cytogenetics in detecting chromosome 7 defects in hematological neoplasias

Monosomy 7 (–7) is one of the most common chromosomal abnormalities found in the leukemic cells of patients with acute myelogenous leukemia (AML) and myelodysplastic syndrome (MDS). Because patients with –7 have a poor prognosis, their identification is important for treatment planning. Conventionally, –7 is detected by the G-banding technique. This study examines the use of fluorescent in situ hybridization (FISH) methodology to detect –7 cells in interphase nuclei and metaphase chromosomes. Fifteen AML or MDS patients whose leukemic cells were found to have –7 by G-banding at disease presentation were studied. In 13 of these patients, –7 could be detected in interphase by FISH using a chromosome 7-specific centromeric DNA probe. The two patients whose leukemic cells were not detectable by interphase FISH had –7 and t(1q;7p), which were detectable by FISH in metaphase using a chromosome 7-specific painting probe. Metaphase FISH was particularly useful in further defining chromosome 7 defects in cells that contained aberrant or marker chromosomes. For example, in 6 patients, chromosome 7 sequences were detectable in aberrant or marker chromosomes by metaphase FISH, but not by G-banding. These results suggest that metaphase FISH is an important adjunct to conventional cytogenetic methods for defining chromosome 7 abnormalities in AML and MDS patients. Furthermore, interphase FISH is useful for follow-up studies in patients who are found informative for the FISH study at presentation.     

CD44与大肠癌

CD44与大肠癌@田慧军$武汉大学人民医院消化内科!武汉430060~~     

Up-regulation of CD44 in rheumatoid chondrocytes

The adhesion molecule CD44 is thought to play an important role in the inflammatory process. To identify the expression of CD44 in articular chondrocytes in rheumatoid arthritis (RA), monoclonal anti-CD44 antibodies were immunohistochemically used to react with articular cartilage specimens of 15 patients with RA, 9 with osteoarthritis (OA), and 6 with femoral neck fracture (FF). The proportion of CD44-positive chondrocytes in RA was 93 +/- 2% (N=16), which was significantly higher than that in OA (59 +/- 7%, N=9, p<0.001) and FF (46 +/- 5%, N=6, p<0.001). Among CD44 isoforms examined, the hemopoietic form was dominant in chondrocytes in RA. Therefore, up-regulation of CD44 on chondrocytes may play a significant role in cartilage degeneration in RA.     

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     

CD44-specific antibody treatment and CD44 deficiency exert distinct effects on leukocyte recruitment in experimental arthritis

CD44, the leukocyte adhesion receptor for hyaluronan, has been considered a therapeutic target on the basis of the robust anti-inflammatory effect of CD44-specific antibodies in animal models of immune-mediated diseases. However, CD44 deficiency does not provide substantial protection against inflammation. Using intravital video microscopy in a murine model of rheumatoid arthritis, we show that CD44 deficiency and anti-CD44 antibody treatment exert disparate effects on leukocyte recruitment in inflamed joints. Leukocyte rolling, which is increased in CD44-deficient mice, is promptly abrogated in anti-CD44-treated wild-type mice. CD44-specific antibodies also trigger platelet deposition on granulocytes and subsequent depletion of this leukocyte subset in the circulation. These in vivo effects require CD44 cross-linking and are reproducible with an antibody against Gr-1, a molecule that, like CD44, is highly expressed on granulocytes. Anticoagulant pretreatment, which prevents platelet deposition, mitigates both granulocyte depletion and the suppressive effect of CD44-specific antibody on joint swelling. Our observations suggest that cross-linking of prominent cell surface molecules, such as CD44 or Gr-1, can initiate a rapid self-elimination program in granulocytes through engagement of the coagulation system. We conclude that the robust anti-inflammatory effect of CD44-specific antibodies in arthritis is primarily the result of their ability to trigger granulocyte depletion.     

CD44v17在胃癌组织中的表达及其与临床生物学特性之间的关系

目的 探讨一种新的CD44变异体（CD44v17）在胃癌组织中的表达及其与临床生物学特性之间的关系.方法根据本实验室在MCF-7／Adr中新发现的1种CD44剪切拼接变异体CD44v17设计特异性引物,应用SYBR Green I荧光染料,采用实时PCR法检测87例胃癌组织及相应癌旁组织CD44v17 Mrna的表达,根据标准曲线计算CD44v17mRNA的表达量,分析CD44v17mRNA表达与胃癌临床生物学特性之间的关系.结果胃癌组织CD44v17 Mrna表达明显高于相应癌旁正常组织（P〈0.05）;肿瘤〉5 cm组CD44v17 Mrna表达与肿瘤≤5 cm组表达比较差异无显著性（P〉0.05）;未分化腺癌组表达明显高于乳头状腺癌及管状腺癌组（P〈0.05）,乳头状腺癌组CD44v17 Mrna表达与管状腺癌组比较差异无显著性（P〉0.05）;肿瘤累及浆膜及浆膜外组CD44v17 Mrna表达显著高于侵及黏膜、黏膜下层及肌层组（P〈0.05）,而肿瘤侵及黏膜及黏膜下层组的CD44v17 Mrna表达与侵犯肌层组表达比较差异无显著性（P〉0.05）.淋巴结转移组CD44v17 Mrna表达明显高于淋巴结无转移组（P〈0.05）;有肝脏转移组CD44v17 Mrna表达显著高于无肝脏转移组（P〈0.05）.结论CD44v17 Mrna在胃癌组织中高表达,可能与胃癌的侵袭、转移及预后有关.     

Expression and clinical significance of CD44V5 and CD44V6 in resectable colorectal cancer

Purpose This study was conducted to evaluate the prognostic significance of CD44v5 and CD44v6 in resectable colorectal cancer.Materials and methods Membranous CD44v5 and CD44v6 levels were measured by an immunoenzymatic assay in tumors and surrounding mucosal samples obtained from 105 patients with resectable colorectal carcinomas.Results There were no significant differences of CD44v5 levels between tumors [median: 3.2 (range: 0.9–83.5) ng/mg protein) and surrounding mucosal samples (3 (3–146.2) ng/mg protein]. However, tumor samples showed significantly higher CD44v6 levels [19.5 (2.2–562.9) ng/mg protein] than mucosal samples [5 (5–230) ng/mg protein] (P=0.0001). Patients with higher CD44v5 or CD44v6 content in tumor samples had a considerably shorter relapse-free survival (P<0.05, for both). Patients with a higher CD44v6 content also had a shorter relapse-free and overall survival in the multivariate analysis (P<0.05).Conclusion The results of this study suggest a role of CD44v5 and CD44v6 in colorectal cancer progression. Membranous CD44v levels in primary tumors, measured by immunoenzymatic assay, may contribute to a more precise prognostic estimation in patients with resectable colorectal cancer.Supported by grants from ISCIII Red de Centros de Cancer RTICCC (C03/10) and Obra Social Cajastur     

CD44 is a phagocytic receptor

CD44, a transmembrane adhesion molecule involved in binding and metabolism of hyaluronan, has additional functions in inflammatory and immune responses, contributing to the ingestion and clearance of particles and apoptotic cells. Our goal was to determine the specific role of CD44 in phagocytosis and whether it functions as a primary or accessory phagocytic receptor. Using hyaluronan-coated beads and erythrocytes coated with antiCD44 antibodies as the phagocytic prey, we determined that CD44 mediates efficient phagocytosis in primary murine peritoneal macrophages and in the murine macrophage cell line RAW 264.7. In RAW cells, the phagocytic index for anti-CD44-coated erythrocytes was 25 +/- 3 (mean +/- SEM) compared with less than 1 for erythrocytes coated with isotype-matched control antibodies. Uptake of anti-CD44-coated erythrocytes was abrogated by pretreatment with a blocking antibody to CD44 and was absent in primary cultures of CD44-deficient murine macrophages. Down-regulation of Fc receptors by aggregated IgG-induced internalization, which blocks uptake of IgG-coated particles, had no effect on CD44-mediated particle engulfment. Using a combination of immunoprecipitation, pharmacologic inhibition, and genetic deletion, we determined that CD44-mediated phagocytosis involves Syk, Rac1, and phosphatidylinositol 3-kinase and induced activation of the phagocyte oxidase. We conclude that CD44 is a competent phagocytic receptor that efficiently mediates internalization of large particles.     

CD44V3、CD44V6和Ki-67在乳腺癌组织中的表达及意义

目的 探讨乳腺癌组织中CD44V3、CD44V6和Ki-67的表达及其与乳腺癌生物学行为的关系.方法 采用组织芯片技术结合免疫组化法检测60例乳腺浸润性导管癌和20例正常乳腺组织中的CD44V3、CD44V6和Ki-67的表达,并分析其与临床病理参数的关系.结果 乳腺癌组织中CD44V3、CD44V6和Ki-67的阳性表达率分别为41.7%、58.3%和68.3%,明显高于正常乳腺组织(P均＜0.05).乳腺癌组织中CD44V6和Ki-67的表达与乳腺癌组织病理分级、淋巴结转移有关(P＜0.05),同时CD44V6的表达与肿瘤的远处转移与否也有关(P＜0.05).乳腺癌组织中CD44V6与Ki-67的表达成正相关(r=0.587,P＜0.01).结论 CD44V6和Ki-67与乳腺癌的恶性生物学行为密切相关,可作为预测乳腺癌转移潜能的指标.     

Induction of CD44 cleavage in articular chondrocytes

Objective

The hyaluronan receptor CD44 provides chondrocytes with a mechanism for sensing and responding to changes in the extracellular matrix. The purpose of this study was to document the fragmentation and loss of CD44 and to determine the likely mechanisms involved.

Methods

A polyclonal anti‐CD44 cytotail antibody was generated to detect CD44 fragmentation by Western blot analysis. Chondrocytes were isolated from human or bovine articular cartilage. Primary articular chondrocytes were treated with interleukin‐1β (IL‐1β), hyaluronan oligosaccharides, or phorbol myristate acetate or were passaged and subcultured in monolayer to induce dedifferentiation. Conditions that altered the capacity of CD44 to transit into lipid rafts, or pharmacologic inhibitors of metalloproteinase or γ‐secretase activity were used to define the mechanism of fragmentation of CD44.

Results

Chondrocytes from osteoarthritic cartilage exhibited CD44 fragmentation as low molecular mass bands, corresponding to the CD44‐EXT and CD44‐ICD bands. Following dedifferentiation of chondrocytes or treatment of primary chondrocytes with hyaluronan oligosaccharides, IL‐1β, or phorbol myristate acetate, CD44 fragmentation was enhanced. Subsequent culture of the dedifferentiated chondrocytes in 3‐dimensional alginate beads rescued the chondrocyte phenotype and diminished the fragmentation of CD44. Fragmentation of CD44 in chondrocytes was blocked in the presence of the metalloproteinase inhibitor GM6001 and the γ‐secretase inhibitor DAPT.

Conclusion

CD44 fragmentation, consistent with a signature pattern reported for sequential metalloproteinase/γ‐secretase cleavage of CD44, is a common metabolic feature of chondrocytes that have undergone dedifferentiation in vitro and osteoarthritic chondrocytes. Transit of CD44 into lipid rafts may be required for its fragmentation.

     

Low serum levels of CD44, CD44v6, and neopterin indicate immune dysfunction in chronic pancreatitis

INTRODUCTION: In autoimmune diseases, malignancies, and inflammatory conditions, a correlation of serum levels of CD44, interleukin-2 receptor (IL-2r), and neopterin with disease activity could be shown. AIMS: To assess the immune parameters in chronic pancreatitis in correlation to clinical data to evaluate the potential role of immune dysfunction as a risk factor. METHODOLOGY: Levels of IL-2r, sCD44, sCD44v6, and neopterin were measured using the enzyme-linked immunosorbent assay in 63 patients with chronic pancreatitis who underwent surgery between 1992 and 1995 in our institution. Clinical data were evaluated prospectively before surgery, and a follow-up investigation was conducted in 1997. RESULTS: Mean serum levels of CD44, CD44v6, and neopterin were significantly lower in patients with chronic pancreatitis compared with the control group. The mean level of IL-2r was also lower in chronic pancreatitis, but this difference was not significant. However, no influence of immunosuppressive factors such as alcohol consumption, cigarette smoking, or diabetes could be detected on the levels of IL-2r, CD44, CD44v6, and neopterin. CONCLUSION: In accordance with other diseases of reduced immunoreactivity, depressed serum levels of biomarkers in chronic pancreatitis are caused by reduced T-lymphocyte and macrophage activation. By ruling out a significant influence of concomitant immunosuppressive factors, we conclude that the inflammatory process itself is the source of the depressed immune function, which might be restored by surgical resection.     

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.     

CD44v3和CD44v6在溃疡性结肠炎与其他类型结肠炎中的表达

目的比较CD44v3和CD44v6在溃疡性结肠炎(UC)与对照组(包括感染性结肠炎、阿米巴痢疾、血吸虫性结肠炎及克罗恩病等其他类型结肠炎)中表达的差异.方法免疫组化SP法检测两组患者结肠粘膜CD44v3和CD44v6的表达.结果 UC组患者CD44v3和CD44v6表达阳性率分别为68.8%和56.3%,与对照组比较有显著性增高(P<0.05).UC组与感染性结肠炎、阿米巴痢疾、血吸虫性结肠炎病及克罗恩病分别比较差异仍有显著性(P<0.05).结论 CD44v3和CD44v6的检测有助于鉴别UC和感染性结肠炎等其他类型结肠炎.     

Expression of CD44 in rat hepatic progenitor cells

BACKGROUND/AIMS: Small hepatocytes (SHs) are hepatic progenitor cells, but the phenotypical difference between SHs and mature hepatocytes (MHs) has never been demonstrated. METHODS: The profile of gene expression was examined to clarify the difference between SHs and MHs by using a DNA microarray. Genes that were specifically expressed in SHs were identified and RT-PCR analysis of them was performed. Immunocytochemistry for CD44 standard form (CD44s) and variant form 6 (CD44v6) was performed using cultured SHs and the d-galactosamine (GalN)-injured rat liver. From the GalN-treated liver, CD44s+ cells were obtained by sorting and RT-PCR analysis was performed. RESULTS: Analysis using the DNA microarray and RT-PCR of them revealed restricted expression of CD44s and CD44v6 in SHs. In culture, CD44s appeared at day 3 and increased with the proliferation of SHs. CD44v6 expression was delayed compared to that of CD44s. With GalN-administration, CD44+ hepatocytes appeared around periportal areas at days 3 and 4 and then decreased. Sorted CD44s+ cells could form colonies and possessed hepatic markers. CONCLUSIONS: CD44 is a specific marker of SHs. The expression of CD44 mRNA and protein is restricted to SHs, and is up-regulated at the time when SHs start to proliferate both in vitro and in vivo.