Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

With increasing emphasis on the early detection of cancer, the search is on for reliable markers that will be clinically helpful in the diagnosis of small tumours and in the assessment of their metastatic potential. This report presents evidence that an abnormal pattern of activity of the CD44 gene is a promising candidate for both of these purposes in various types of malignancy. By a mechanism known as alternative splicing this gene can produce different messenger RNA molecules (transcripts) which are detectable, after amplification, as separate bands in electrophoretic gels. In neoplasia many abnormal variant transcripts are produced. A previous finding in animal experiments, that one such variant might be important in metastasis, prompted our study of human tumour tissue, benign and malignant, and of corresponding normal tissues. We studied tumour tissue from 34 patients with neoplastic disease (mostly breast or colon cancer) and normal or non-malignant diseased breast or colonic tissue from 11 patients and peripheral blood leucocytes from 4 healthy volunteers. CD44 gene activity was studied by amplifying messenger RNA with the polymerase chain reaction (PCR) followed by electrophoresis and blot hybridisation. In malignant tissues there was gross overproduction of each of 9 or more alternatively-spliced large molecular variants in all samples, whereas in the control samples only the standard product was routinely detected with occasional minimal quantities of one or two small variants. Furthermore, the band pattern permitted differentiation between the 23 cases with metastatic tumours of the breast or colon and the 8 with no detectable metastases. Calibration studies seeding blood with tumour cells showed that the technique can detect as few as 10 tumour cells among 10(7) leucocytes (1 ml of blood). Analysis of CD44 splice variants may prove to have applications not just to the early detection of metastatic potential in surgical biopsy specimens but also, if our findings are confirmed, in readily available bodily fluids, to the early diagnosis of cancer in screening programmes, to the assessment of remaining disease in the body and to the early detection of recurrences.
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PMID:Significance of CD44 gene products for cancer diagnosis and disease evaluation. 809 44

Cancer metastasis poses the greatest challenge to the eradication of malignancy. The majority of clinical and experimental evidence indicates that metastasis is a non-random, organ-specific process. Tumor cell interaction with endothelium and subendothelial matrix constitutes the most crucial factor in determining the organ preference of metastasis. A plethora of cell surface adhesion molecules, which encompass four major families (i.e., integrins, cadherins, immunoglobulins and selectins) and many other unclassified molecules, mediate tumor-host interactions. Adhesion molecules and adhesion processes are involved in most, if not all, of the intermediate steps of the metastatic cascade. Decreased E-cadherin expression and increased CD44 expression are clearly correlated with the acquisition of the invasive capacity of primary tumor cells. Similarly, altered expression pattern of many other adhesion molecules such as upregulated expression of the laminin receptors and depressed expression of fibronectin receptors (alpha 5 beta 1) appears to be involved in tumor cell invasion into the subendothelial matrix. Tumor cell-endothelium interactions involve several well-defined sequential steps that can be analyzed by the 'Docking and Locking' hypothesis at the molecular level. Tumor cell-matrix interactions are determined by the repertoire of adhesion receptors of tumor cells and the unique composition of organ-specific matrices. Our experimental data, together with others', suggest that the integrin alpha IIb beta 3 is one of the major players in these tumor-host interactions. Tumor-host interaction is a dynamic process which is constantly modulated by a host of factors including various cytokines, growth factors and arachidonate metabolites such as 12(S)-HETE. Delineation of the molecular mechanisms of tumor-host interactions may provide additional means to intervene in the metastatic process.
Cancer Metastasis Rev 1992 Nov
PMID:Adhesion molecules and tumor cell interaction with endothelium and subendothelial matrix. 142 22

Recently, many surface proteins of lymphoid cells that mediate adhesion to other cells and extracellular matrix have been identified. Several of these cellular adhesion molecules (CAM) are also expressed by metastatic lymphoma cells and may mediate adhesion to tissue components during the metastatic process. Correlations observed between expression of certain CAM, like MEL-14 and CD44, and particular patterns of spread, support this notion, but conclusive evidence is scarce. We have used T-cell hybridomas to study the mechanisms of wide-spread lymphoid metastasis. The results obtained with this model are reviewed here. The advantages are that a large number of genetically similar cell lines can be generated, which can be grouped in large panels of highly invasive and non-invasive cells. Invasiveness of these cells in hepatocyte and fibroblast monolayers correlates with experimental metastasis. Lymphoid CAM that are potentially involved in metastasis are reviewed. Several of these CAM are not, or not consistently, expressed by the invasive T-cell hybridomas, indicating that they are not indispensable. Notably, some of the CAM involved in the onset of an immune response or in migration into inflamed tissues, like ICAM-1 and VLA-4, and the 'homing receptors' MEL-14 and LPAM-1 do not seem to be involved. CAM that are consistently expressed by the T-cell hybrids include LFA-1, the beta-1 integrin subunit CD29, CD31 (PECAM-1) and CD44 ('Hermes homing receptor'). We have generated considerable evidence that LFA-1 is required for efficient metastasis of T-cell hybrids, based on the behavior of LFA-1-deficient mutants and revertants. High levels of LFA-1 are required. The relevant counterstructure is probably ICAM-2 rather than ICAM-1. Preliminary results suggest that also a beta-1 integrin, possibly VLA-5, plays a role. Finally, we summarize evidence indicating that CD31 and CD44 are primary candidates for involvement in metastatic spread of T-cell hybridomas.
Cancer Metastasis Rev 1991 May
PMID:Adhesion molecules in lymphoma metastasis. 168 May 76

Frozen tissue sections obtained from human glioblastomas, brain tumor metastases and normal brain were examined for the expression of molecules known to be involved in lymphocyte activation and/or adhesion and migration. The molecules studied included CD3, CD45R, UCHL-1 (CD45RO), lymphocyte function-associated antigen 1 (LFA-1) (CD11a, CD18), intercellular adhesion molecule 1 (ICAM-1) (CD54), 4B4 (CD29), CD44, CD2, and LFA-3 (CD58). CD3+ lymphocytes infiltrating human glioblastomas and brain tumor metastases expressed LFA-1 alpha and beta. Many cells were also UCHL-1+ whereas only a small percentage were CD45R+. CD2+ lymphocytes were also present. Tumor-infiltrating lymphocytes (TIL) were found to be negative for CD29, which was, however, expressed on intratumoral vessels in addition to vessels found in normal brain. Glioblastoma cells and intratumoral vessels expressed ICAM-1 whereas no ICAM-1 was found on TIL or on normal brain. Glioblastoma cells also expressed high levels of both CD44 and LFA-3 whereas TIL were negative for these antigens. CD44 was also expressed on certain regions of normal brain. Antibodies to LFA-1 alpha and -beta and ICAM-1 could significantly block the binding of lymphokine-activated killer (LAK) cells or TIL to human glioblastoma cells suggesting that these molecules play a role in the binding and subsequent migration of lymphocytes into brain tumor tissue.
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PMID:Activation and adhesion molecule expression on lymphoid infiltrates in human glioblastomas. 169 16

A Burkitt's lymphoma (BL, EBV +, 8/22 translocation), the EBV immortalized lymphoblastoid cell line from the same individual (LCL) and somatic cell hybrids (HYB) between both cell lines were inoculated in immunedeficient scid mice. Subcutaneous injected BL cells produced local tumor masses without distant metastases. In contrast LCL and hybrids show invasive and disseminated growth. Peripheral lymph nodes and thymic tissue were preferentially colonized. A detailed phenotypic analysis of BL, LCL and 3 different hybrids was performed using differntiation and adhesion molecules. The preferential "homing" of LCL and hybrids seem to be correlated with the expression of the lymphocyte homing receptor (CD44). The growth of LCL in scid mice shows, that additional genetic alterations are not necessary to cause a malignant phenotype. Activation of myc seem to play a minor role, because hybrids mimic the LCL phenotype and distribution pattern.
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PMID:[Invasive, metastatic growth of lymphoblastoid B cells in immunodeficient SCID mice]. 172 38

Many steps in melanoma metastasis involve cell-cell or cell-matrix adhesive interactions. The surface molecules which mediate these processes therefore play an important role in regulating melanoma dissemination and their level of expression may alter during the course of tumor progression. Human melanocyte strains and melanoma cell lines have been characterised with regard to levels of cell surface receptors of the integrin family. Increased amounts of at least two integrins, VLA-4 (alpha 4 beta 1) and VnR (alpha v beta 3), appeared to correlate with progression in this tumor, type. A novel VnR composed of an alpha v beta 1 association has been observed in one melanoma cell line and there is the possibility that heterogeneity of integrin composition could affect biological behavior of these tumors. CD44, a cell surface glycoprotein which functions as the major receptor for hyaluronate, is another molecule whose expression increases in transformed cells of the melanocytic lineage. Iterative sorting on the FACS for stable variants, of both human and murine melanomas, expressing low and high levels of CD44 established that lack of expression of this molecule correlated with impaired ability to form pulmonary tumor nodules subsequent to i.v. injection into appropriate recipient mice. These findings illustrate that an understanding of the regulation of melanoma adhesion receptors could provide insights into the process of tumor spread.
Cancer Metastasis Rev 1991 Jun
PMID:Cell adhesion receptor expression during melanoma progression and metastasis. 187 52

Endocrine pancreatic tumors are neuroendocrine neoplasms with malignant potential and give rise to varied clinical syndromes due to excessive secretion of multiple hormones. In this study 22 endocrine pancreatic tumors and 11 carcinoid tumors were examined for the expression of CD44 using a monoclonal antibody. CD44 gene activity of 11 endocrine pancreatic tumor tissues and five carcinoid tumor tissues was also studied by amplifying messenger RNA with the polymerase chain reaction followed by electrophoresis and blot hybridization. Strong immunoreactivity was detected on all gastrinomas examined (P < 0.001), and in two non-functioning endocrine pancreatic tumors. Such immunoreactivity was not observed in other subtypes of endocrine pancreatic tumors. In the normal human pancreas, the acinar portion and ductal epithelial cells stained strongly positive but pancreatic islet cells did not show any significant immunostaining. Furthermore, in endocrine pancreatic tumors with metastatic disease, CD44-positive tumors had a tendency to metastasize to lymph nodes (P = 0.005), as compared with CD44-negative tumors which were locally invasive or metastasized to the liver. Although, in this limited material and short follow-up, we were not able to show any statistical significance, patients with CD44-negative endocrine pancreatic tumors had prolonged survival time compared with patients with CD44-positive tumors (73% versus 59% at 5 years; P = 0.7). Of 10 carcinoid tumors examined, all three foregut carcinoids and one midgut carcinoid stained strongly positive, whereas all other midgut carcinoids were negative. Analysis of CD44 splice variants showed that in all five gastrinomas there was overproduction of alternatively spliced larger molecular variants as compared with other types of endocrine pancreatic tumors and carcinoid tumors. The band pattern from one case of carcinoid tumor with a fulminant clinical course was similar to that of gastrinomas, whereas other carcinoid tumors expressed the epithelial form of CD44. The earlier identified splice variants which confer metastatic behavior on a pancreatic tumor cell line were not expressed in neuroendocrine tumors. Our data indicate that CD44 expression in endocrine pancreatic tumors correlates with the ability to give rise to lymph node metastases and may play a vital role in determining the fate of metastasizing cells. Moreover, because gastrin is not detectable in the normal human pancreas, the pancreatic ductal cell positivity for CD44 strengthened the ductal origin concept of gastrinomas. The band pattern of CD44 splice variants suggests that the previously described splice variants conferring metastatic behavior do not accompany metastatic activity of neuroendocrine tumors.
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PMID:Different splice variants of CD44 are expressed in gastrinomas but not in other subtypes of endocrine pancreatic tumors. 750 23

Expression of CD44, the cellular hyaluronate receptor, was examined in human prostate cell lines. CD44 mRNA was detected in cell lines PC3 and DU145, both established from organ metastases of prostate adenocarcinoma, but not in cell line LNCaP, established from a lymph node metastasis. PC3 and DU145, but not LNCaP, are tumorigenic and metastatic in nude mice. Of the CD44 mRNA species identified, the standard CD44s as well as variant isoforms CD44v7, CD44v10, CD44v14, CD44v13-v14, CD44v12-v14 and CD44v7-v14 are represented.
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PMID:Expression of CD44 in prostate cancer cells. 751 Feb 14

Identification of antigens by monoclonal antibodies (MAbs) on sections of human melanoma by immunoperoxidase techniques was used to determine whether certain adhesion molecules and "selectin-like" molecules may be related to the metastatic potential of primary melanoma. The adhesion molecules examined were the leukocyte function antigen (LFA-1) and its ligand--intercellular adhesion molecule-1 (ICAM-1), the receptor alpha V beta 3 for vitronectin, its subunits alpha V and beta 3, and the CD36 receptor for thrombospondin (TSP). The criteria used to establish metastatic potential were relation of the molecules to tumor thickness and differences in expression: (i) between radial and vertical growth phases of the primary tumors and (ii) between 34 primary and 21 unrelated metastases. By these criteria ICAM-1, alpha V beta 3 and its subunit were associated with the malignant potential of primary melanoma. These molecules were not expressed on nevi or other skin cancers with low metastatic potential such as squamous (SCC) and basal cell carcinomas (BCC). In contrast, expression of TSP and the CD36 receptor for TSP were not related to metastatic potential. CD36 was expressed widely not only on melanoma but also on BCC, SCC and nevi. Similarly, the selectin-like molecule, CD44, was widely expressed on melanoma and non-melanoma carcinomas. The lymph node homing receptor, Leu 8, and the cutaneous lymphocyte antigen (CLA) were not detected on melanoma. Leu 8 was present on normal epithelium and SCCs, and common leucocyte antigen (CLA) was detected on lymphocytes in the epithelium and near melanoma. These results support previous suggestions that expression of ICAM-1 and V beta 3 integrin or its subunit beta 3 on melanoma may be a useful prognostic marker in primary melanoma. They do not support a role for CD44, Leu 8, CLA and TSP or its receptor CD36 in the metastatic process in melanoma.
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PMID:Immunohistological examination of the relationship between metastatic potential and expression of adhesion molecules and 'selectins' on melanoma cells. 751 76

Expression of the CD44 molecule has been linked to tumor growth and metastases in both human and rodent cancers. Alternatively spliced variants expressed in rat and mouse tumors have been shown to confer metastatic potential to non-metastatic carcinoma cell lines, and human homologues of rat variant mRNA sequences are expressed in human tumors. In the present study matched sets of RNA from adenocarcinomas of the colon and distant normal mucosa were assayed for CD44 expression by quantitative RT-PCR. Retrospective analysis revealed that colonic tumor cells had both quantitative and qualitative differences in CD44 expression when compared to normal mucosa. These were: 1) an increase in levels of CD44 transcripts, 2) an increase in levels of alternatively spliced transcripts, 3) the presence of larger alternatively spliced transcripts with inserts > 400 bases and 4) the primary alternatively spliced CD44 isoform in colonic adenocarcinomas in all cases is CD44R. Interestingly, two patterns of CD44 isoform expression termed "variant dominant" or "balanced" patterns of expression, based on the ratio of variant to standard CD44 transcripts (R+V's/H), could be differentiated. An unfavorable prognosis was suggested for tumors expressing increased levels of CD44 variant exons previously associated with tumor metastasis. Specifically, patients with tumors expressing the "variant dominant" pattern of expression irregardless of Dukes classification and Dukes C and D staged tumors of both patterns exhibited a poorer prognosis.
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PMID:Alternative splicing of CD44 pre-mRNA in human colorectal tumors. 751 91


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