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Results for “Integrin alpha2”

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PubMedDate not supplied

Differential expression of transforming growth factor alpha, adhesions molecules and integrins in primary, metastatic liver tumors and in liver cirrhosis.

Changes in cytokines, intercellular cell-matrix adhesion molecules and integrins may influenced tumor cell invasion and metastases. This study described the distribution, pattern and intensity of cytokine TGFa, adhesion molecules CD 34 and CD 44 and integrins a2, a3, CD 29 (beta 1 chain) and CD 61 (beta 3 chain) in hepatocellular carcinoma (HCC), metastatic liver tumors and hepatic cirrhosis. Fresh snap-frozen tissue from 20 cases of HCC, 5 metastatic adenocarcinomas and 10 cirrhotic livers was studied immunohistochemically using available antibodies. The most intense staining of TGFa was found in metastatic adenocarcinoma, following by regenerating hepatocytes in cirrhotic liver and well differentiated HCC. Insignificant differences in activity of CD 34 in various pathologies, up-regulation of CD 44 in poorly differentiated HCC and down-regulation in metastatic tumors were found. All integrins studied showed down-regulation in poorly differentiated HCC, relatively high activity of a2, a3 and beta 1 in metastatic tumors and the presence of all integrins in cirrhotic liver.

Adenocarcinoma↗

PubMed1995

Regulation of alpha 2 integrin gene expression in cells with megakaryocytic features: a common theme of three necessary elements.

The alpha 2 beta 1 integrin mediates interactions between cells and the extracellular matrix molecules, collagen and/or laminin. The alpha 2 beta 1 integrin is expressed in a variety of cell types, but in cells of hematopoietic lineage, expression is restricted to megakaryocytes and platelets. Increased expression of the alpha 2 beta 1 integrin during megakaryocytic differentiation is a consequence of transcriptional activation of the alpha 2 gene. We have begun to characterize the role of the 5' flanking region of the alpha 2 integrin gene in regulating expression during megakaryocyte differentiation. A 5-kb fragment of the 5' region directs both cell type and differentiation-dependent expression of a reporter gene in the pluripotent hematopoietic K562 cells upon megakaryocytic differentiation and in the megakaryocytic cell line, Dami. Analysis of a series of 5' deletion mutants indicates that expression of the alpha 2 integrin gene in cells with megakaryocytic features requires a core promoter region, a silencer region, and megakaryocytic enhancers in the distal 5' end. The organization of these three distinct regulatory regions of the alpha 2 promoter/enhancer suggests a common theme for megakaryocytic gene regulation shared with other megakaryocyte-specific proteins, including alpha IIb integrin subunit and platelet factor 4.

Antigens, CD↗

PubMedDate not supplied

The intracellular distribution of vinculin and alpha 2 integrin in epithelial cells and chondrocytes.

The purpose of this study was to demonstrate the presence of vinculin and alpha 2 integrin in chondrocytes in situ and epithelial cells. We also determined that the appropriate fixation and extraction protocols for immunohistochemistry and laser scanning confocal microscopy for an integral membrane protein and an actin-associated protein in cultured cells and whole tissue was different. Cultured epithelial cells, whole mount human cornea and avian cartilage were fixed and prepared using a number of standard procedures used for indirect fluorescence immunohistochemistry. The distribution of vinculin was cell-type and fixation-specific. Chondrocytes and cultured epithelial cells demonstrated vinculin in areas that appear to be associated with filamentous actin. Vinculin was associated with cell membranes in human cornea. The expression of alpha 2 integrin observed in chondrocytes fixed with methanol, paraformaldehyde, or formaldehyde is consistent with its role in cell-substrate interaction, but may also suggest a role in dividing and differentiating cells. The localization of alpha 2 integrin in human corneal epithelia supports its role as a cell-cell adhesion molecule. The cytoplasmic distribution of vinculin and alpha 2 integrin in tissues fixed without detergent extraction suggests that the fixation step may be sufficient for antibody penetration and antigen extraction. These studies are the first report of vinculin and alpha 2 integrin in embryonic chondrocytes. In addition we have shown that confocal laser scanning microscopy combined with proper fixation and extraction protocols may optimize the localization of antigens in cultured and whole mount cells.

Animals↗

PubMed1994

The human alpha 2 integrin gene promoter. Identification of positive and negative regulatory elements important for cell-type and developmentally restricted gene expression.

The alpha 2 beta 1 serves as a collagen receptor or a collagen/laminin receptor, depending upon cell type. Expression of the integrin is regulated during normal cellular differentiation and is altered during carcinogenesis. We have previously demonstrated that increased expression of the alpha 2 beta 1 integrin during megakaryocytic differentiation is a consequence of increased alpha 2 mRNA due to transcriptional activation of the alpha 2 integrin gene and that the decreased expression of the integrin in breast adenocarcinoma is due to decreased steady-state levels of alpha 2 mRNA. We now report the identification and characterization of the 5'-flanking region of the alpha 2 integrin gene. The 5'-untranslated region of the alpha 2 mRNA extends 129 base pairs 5' to the site of translation initiation. The promoter region lacks TATA and CAAT boxes but contains an abbreviated initiator sequence and six Sp1 binding sites. Consensus binding sites for AP-1 and AP-2 complexes, a GATA box, a Pu.1 box, and two palindromic motifs with potential to bind the estrogen receptor are also present. A 961-base pair fragment of the 5'-flanking region directs both cell type- and differentiation-specific expression of a reporter gene in T47-D epithelial cells and in pluripotent hematopoietic K562 cells upon megakaryocytic differentiation.

Amino Acid Sequence↗

PubMed1993

[Evaluation of the microplate enzyme-linked assay with isolation of glycoprotein IIb/IIIa from platelet membranes: comparison with immunofluorescent tests and monoclonal antibodies].

The enzyme test with GPIIb/IIIa has been used to detect antibodies in 500 sera from patients with thrombocytopenia and mothers of infants with thrombocytopenia. The results were compared with antibody detection in the platelet suspension immunofluorescence test (PIFT) and in the monoclonal antibody immobilization of platelet antigens (MAIPA). Platelet antibodies were detected in 125 sera (25%). In 46.2% the results were positive in all three tests. However, in 38.4% the ELISA was negative while the PIFT and MAIPA were positive. On the other hand, in 14.4% the ELISA was positive while the PIFT and/or the MAIPA were negative. The ELISA appears to be useful in the detection of anti-HPA-1a antibodies, which are the main cause of AIMN and PTP. This test, however, seems to be less useful in the detection of autoantibodies. The significance of the ELISA in the detection of platelet alloantibodies responsible for refractoriness to platelet transfusions is not clear yet and requires further investigations.

Antibodies, Monoclonal↗

PubMed1995

Natural human interferon-alpha enhances the expression of intracellular adhesion molecule-1, integrin alpha 2 and beta 1 by a mucosal epithelial cell line.

We have found that pretreatment of a human oral mucosal epithelial cell line KB with natural human interferon-alpha (IFN-alpha) augments the expression of intercellular adhesion molecule-1 (ICAM-1), and the complex of CD29 and CD49b, which is known as very late antigen (VLA)-2, in a dose-dependent manner, whereas the expression of other adhesion molecules such as CD44 leukocyte function associated antigen-3 (LFA-3), VLA-4 and endothelial leukocyte adhesion molecule-1 (ELAM-1) did not show any significant changes under the same conditions. The pretreatment of KB cells with IFN-alpha also induces the adhesion of these cells to the human leukemia T cell line MOLT-16 and to peripheral T lymphocytes in a dose-dependent manner. However, the adhesion of the above-mentioned T cells to KB cells was not inhibited by specific antibodies against ICAM-1, CD29, and CD49b. The results thus show that adhesion molecules other than ICAM-1, CD29, AND CD49b are responsible for the induced adhesion between T cells and IFN-alpha-pretreated KB cells.

Antigens, CD↗

PubMed1996

Cloning and characterization of fetal liver phosphatase 1, a nuclear protein tyrosine phosphatase isolated from hematopoietic stem cells.

We report the isolation of cDNAs encoding protein tyrosine phosphatases (PTPs) from highly purified hematopoietic stem cell populations. One such cDNA encodes a novel PTP, designated fetal liver phosphatase 1 (FLP1), which consists of one PTP domain followed by a carboxy terminal domain of 160 amino acids. Northern blot and in situ hybridization analysis showed that expression of FLP1 mRNA is restricted to thymus in 15.5-day-old and 17.5-day-old mouse embryos and to kidney and hematopoietic tissues in adult mice. Furthermore, polymerase chain reaction-based analysis shows that FLP1 is expressed in hematopoietic stem cells as well as in more mature hematopoietic cells. Peptide antisera against FLP1 immunoprecipitated a 48-kD protein that is localized in the nuclei of Ba/F3 lymphoid cells. We have analyzed the effects of overexpressing either wild-type FLP1 or a functionally inactive mutant of FLP1 in hematopoietic cells. In the progenitor K562 cell line, cells ectopically expressing functional FLP1 differentiated normally to megakaryocytes after induction with tetradecanoyl phorbol acetate (TPA). In contrast, when K562 transfectants expressing an inactive mutant FLP1 protein were treated with TPA, the characteristic cell spreading and substrate adhesion that accompany megakaryocytic differentiation did not occur. We show that, in these cells, the induction of the differentiation marker alphaIIb beta3 is not affected. However, both constitutive and TPA-induced expression of alpha2 integrin, a late megakaryocytic marker, are inhibited. These results suggest that the expression of an inactive form of FLP1 affects late signaling events of K562 megakaryocytic differentiation.

Amino Acid Sequence↗

PubMed1996

Integrin alpha 2 beta 1 in tumorigenic human osteosarcoma cell lines regulates cell adhesion, migration, and invasion by interaction with type I collagen.

Human osteosarcomas are aggressive bone tumors. Here we propose that their progression requires altered cell interaction with extracellular matrix. Since type I collagen is the main matrix molecule found in bone and thus obligated to interact with tumor cells, we analyzed the expression and function of different integrin-type collagen receptors in tumor cell-collagen interaction by using eight human osteogenic sarcoma (HOS) cell lines. Virally (Kirsten sarcoma virus) transformed derivatives of HOS cells (KHOS-NP) and chemically [N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)] transformed tumorigenic subclones of human osteogenic sarcoma cells (HOS-MNNG) expressed alpha 2 beta 1 integrin in remarkably larger amounts than the six other nontumorigenic cell lines (HOS, MG-63, Saos-2, KHOS-240, KHOS-312, and G292). Concomitantly, Mg(2+)-dependent adhesion of tumorigenic cells to type I collagen was increased. We also show that the migration of tumorigenic cells on and invasion through type I collagen is faster than that of HOS cells. HOS cells forced to express alpha 2 integrin by cDNA transfections showed increased Mg(2+)-dependent cell adhesion to type I collagen and also accelerated migration and invasion rate, indicating that the overexpression of alpha 2 beta 1 integrin in tumorigenic cells alone explains the altered cell-collagen interaction. Finally, HOS cells forced to express alpha 2 integrin subunit did not grow s.c. in athymic mice, suggesting that overexpression of alpha 2 integrin is not efficient to make these cells tumorigenic.

Animals↗

PubMed1997

Integrin expression on normal and neoplastic human breast epithelium.

Integrin adhesion receptor expression of different benign and malignant breast tumours was examined by means of immunohistochemical techniques. A panel of seven different anti-alpha and two different anti-beta subunit antibodies was used. Normal breast epithelium displayed a well characterized and constant pattern of integrin expression consisting of strong alpha 1,2,3,6 and alpha v, and a relatively weaker beta 1 and beta 3 staining. No staining for alpha 4 or alpha 5 could be detected on the epithelial cells. Benign fibroadenomas did not show changes in their receptor expression compared to normal tissues. In the cases of different types of breast cancer, there was a significant downregulation of all subunits. The staining pattern was distinct if there could a basement membrane like structure be detected around the invading tumour nodules. When laminin and collagen type IV surrounded the tumour cells, those cells in contact with the extracellular matrix components still displayed strong positivity for the integrin subunits. Other cells inside the tumour cell nests or not surrounded by basement membrane did not express integrins. The positively staining cells might be more differentiated owing to the effect the basement membrane. Myoepithelial labeling of the integrin expressing cells gave negative results. The observed integrin expression heterogeneity renders the histologic picture difficult to interpret with regard to clinical behavior of the tumour.

Antibodies↗

PubMed1998

Evidence that CD31, CD49b, and CD62L are immunodominant minor histocompatibility antigens in HLA identical sibling bone marrow transplants.

Despite complete matching of siblings for the HLA loci, after bone marrow transplantation (BMT), approximately 20% develop graft-versus-host disease (GVHD). This is presumably due to incompatibility of minor histocompatibility antigens (mHa). We investigated the polymorphisms of 14 adhesion molecules (CD2, CD28, CD31, CD34, CD36, CD42, CD44, CD48, CD49b, CD54, CD62L, CD86, CD102, and CD106) in Japanese subjects and their association with the occurrence of GVHD after allogeneic HLA identical BMT. Six molecules (CD2, CD31, CD42, CD49b, CD54, and CD62L), which were found to be polymorphic, were then examined in 118 HLA identical sibling donors and recipients who had undergone BMT. Association of the incompatibility of the polymorphic molecules with the presence or absence of GVHD was examined. In these six, we observed a significant correlation between acute GVHD and the compatibility of CD31 (codons 563/670) (Pcorrected = .018), and CD31 (codons 563/670) + CD62L (Pcorrected = .018) in patients with the HLA-B44-like superfamily. In patients with the HLA-A3-like superfamily, the compatibility of CD62L (Pcorrected = .03) and CD62L + CD49b (P = . 004, Pcorrected = .078) was associated with acute GVHD. Therefore, CD31, CD49b, and CD62L might be candidates for immunodominant mHa.

Adolescent↗

PubMed1998

Platelet glycoprotein Ia* is the processed form of multimerin--isolation and determination of N-terminal sequences of stored and released forms.

Glycoprotein Ia* (GPIa*), a very high molecular mass, platelet alpha-granule protein consisting of 167 kDa subunits disulphide-linked in a multimeric structure, was first described by Bienz and Clemetson in 1989 (J. Biol. Chem. 264, 507-514). In 1991 Hayward et al. (J. Biol. Chem. 266, 7114-7120) independently identified a platelet protein with multimeric structure. Despite strong similarities to GPIa* they concluded that it was a novel multimeric protein and named it first p-155 and later, multimerin. Multimerin has also been found in endothelial cells and has been cloned recently from an endothelial cell cDNA library. This has made it possible for us to clarify the relationship between GPIa* and multimerin. GPIa* was isolated from platelet releasate and the N-terminal sequence of 167 kDa and 155 kDa subunit species were determined. The N-terminal 15 amino acids of GPIa* were identical to the deduced amino acids 184-198 of endothelial multimerin. The N-terminal sequence of the 155 kDa protein was identical to the deduced amino acids 318-326 of multimerin. Thus, platelet GPIa* (167 kDa) is the main processed form of multimerin stored in platelet alpha-granules. The GPIa*/processed multimerin (167 kDa) still contains an RGDS sequence near its N-terminus as well as an EGF domain which may be involved in binding to the platelet surface after release. This sequence and domain are cleaved off in the p-155 form, described earlier as platelet multimerin, which is probably formed after release from alpha-granules.

Amino Acid Sequence↗

PubMed1999

Dominant role of E-cadherin in the progression of bladder cancer.

PURPOSE: To elucidate factors with a role in the progression of bladder cancer. MATERIALS AND METHODS: One invasive (T24) and two superficial (RT4 and KK47) human bladder cancer cell lines, which express metastasis-related genes, were used. Cells were intravenously inoculated into chick embryos to evaluate metastatic potential to the liver. An orthotopic model with severe combined immunodeficiency mice was also used to investigate both histological appearance and changes in metastasis-related gene expression. Finally, gene expression patterns in a clinical setting were compared between superficial and invasive bladder cancers. RESULTS: In culture condition metastasis-related genes, including matrix metalloproteinases, urokinase-type plasminogen activator, and integrins alpha2 and alpha3 were continually expressed in T24 but only slightly or not at all in RT4 and KK47, respectively. The expression pattern of the metastasis-related genes in vitro reflected the characteristics of the original tumors. Liver metastasis in chick embryos was demonstrated not only with T24 cells, but also with RT4 cells in which enhanced expression of metastasis-related genes was induced. In the orthotopic model, histological appearances were in accordance with the characteristics of the original tumors, although enhanced gene expression was notable with RT4. Expression of E-cadherin by Western blotting was demonstrated only with RT4 under these experimental conditions. Furthermore, predominant E-cadherin mRNA expression was found in superficial and not in invasive human primary bladder cancers; expression of other genes was similar in the two groups. Dominant expression of E-cadherin in superficial tumors was confirmed by immunohistochemical analysis. CONCLUSIONS: These results implicate loss of E-cadherin expression as a critical factor in facilitating the progression of bladder cancer.

Animals↗

PubMed1999

Activated T cells acquire endothelial cell surface determinants during transendothelial migration.

Activated T cells acquire endothelial cell (EC) plasma membrane constituents during transendothelial migration. This was assessed using an in vitro model system in which human peripheral blood CD4+ T cells migrated through confluent monolayers of HUVEC. Flow cytometry of migrated CD4+ T cells demonstrated that activated, but not resting, T cells acquired a variety of endothelial surface determinants, including CD31, CD49d, CD54, CD61, and CD62E. The extracellular domains of these molecules were detected on migrated T cells with mAbs, including those directed to the ligand-binding regions. A number of approaches were employed to document that the acquisition of these molecules was uniquely accomplished by activated T cells and clearly involved transfer from both resting and TNF-alpha-activated EC. Acquisition of endothelial markers by activated T cells occurred as part of the transfer of membrane components, as migrating T cells acquired EC membranes prelabeled with the lipophilic dye, 3,3'-dihexadecyloxacarbocyanine perchlorate (DiOC-16), along with EC surface proteins. Thus, during transendothelial migration, activated T cells acquire endothelial membrane components, and as a result may deliver them to perivascular sites.

Antigens, CD↗

PubMed2002

Expression of integrins by human periodontal ligament and gingival fibroblasts and their involvement in fibroblast adhesion to enamel matrix-derived proteins.

We showed recently that human periodontal ligament (PDL) and gingival fibroblasts adhere and spread on enamel matrix protein (EMP) coatings. In the present study, we investigated whether this interaction can be attributed to integrin expression. Human PDL and gingival fibroblasts were cultured for periods up to 24 h on EMP coatings, in the presence of synthetic RGD-containing peptide or an antibody against the beta1 integrin subunit. The cells were first cultured for 24 h under serum-free conditions and then cultured on EMP coatings for 48 h. Integrin expression levels were assessed by flow cytometry analysis. It was found that attachment and spreading on EMP was inhibited by the synthetic RGD-containing peptide, but not by a synthetic RGE-peptide. Both PDL and gingival fibroblasts showed expression of the integrin subunits, alpha2, alpha5, beta1, and the integrin, alphavbeta3. Incubation with an antibody against the beta1 subunit significantly inhibited the attachment and spreading of PDL and gingival fibroblasts on EMP coatings. We conclude that integrins are involved in the interaction of PDL and gingival fibroblasts with EMP.

Adolescent↗

PubMed1997

Migration of highly aggressive MV3 melanoma cells in 3-dimensional collagen lattices results in local matrix reorganization and shedding of alpha2 and beta1 integrins and CD44.

The three-step model of cell migration consisting of protrusion of a leading lamella, attachment to the substrate, and contraction of the cell body is well established for fibroblasts migrating across planar surfaces. However, it is not resolved to what extent the migration of cancer cells in a 3-dimensional tissue environment follows similar principles. Here, we present evidence that the migration of highly invasive MV3 melanoma cells in 3-dimensional collagen matrices follows the three-step concept of migration but also results in characteristic reorganization of the extracellular matrix. After incorporation in the lattice, MV3 cells spontaneously developed a slow type of migration (mean velocity, 0.19 microm/min), leading to alignment of collagen fibers at attachment sites, as detected from unfixed and fixed samples by confocal reflection contrast in combination with immunofluorescence staining. In the process of migration, the formation of focal clusters or stripes of alpha2 and beta1 integrins colocalized with binding sites to collagen fibrils at the leading as well as the trailing edge. In contrast, CD44 was nonclustered and redistributed toward the rear end of the cell. At detachment sites, dynamic fiber traction, localized fiber disruption, and the release of cell surface determinants, including alpha2beta1 integrins and CD44, resulted in circumscribed matrix reorganization. Not infrequently, these emerging tube-like paths of least resistance bordered by a dense fiber network facilitated the reorientation and contact guidance of proximate MV3 cells to migrate along the preexisting path. In conclusion, the migration of MV3 cells in 3-dimensional collagen lattices resulted in dynamic tissue reorganization and receptor shedding the consequences of which were directly visualized by combining confocal reflection imaging with immunofluorescence.

Animals↗

PubMed2006

Biological activity of rainbow trout Ea4-peptide of the pro-insulin-like growth factor (pro-IGF)-I on promoting attachment of breast cancer cells (MDA-MB-231) via alpha2- and beta1-integrin.

E-peptide of pro-IGF-I was considered as biologically inactive. We have demonstrated that rainbow trout (rt) Ea4-peptide exerted biological activities in several established tumor cell lines [Chen et al., 2002; Kuo and Chen, 2002]. Here we report the activity of rtEa4-peptide in promoting attachment of human breast cancer cells (MDA-MB-231). While rtEa2-, rtEa3-, and rtEa4-peptides enhanced the attachment of MDA-MB-231 cells in a dose dependent manner, rtEa4-peptide possessed the highest activity. Antibodies specific to alpha2 and beta1 integrins significantly inhibited the attachment of cells to rtEa4-peptide coated-plates by 40%. In addition, rtEa4-peptide induced the expression of fibronectin 1 and laminin receptor genes in MDA-MB-231 cells. Blocking new protein synthesis by cycloheximide significantly reduced the attachment of MDA-MB-231 cells to rtEa4-peptide coated wells by 50%. These results suggest that rtEa4-peptide may promote cell attachment by interacting with alpha2/beta1 integrin receptors at the cell surface and by inducing the expression of fibronectin 1 and laminin receptor genes. Expression of fibronectin 1 gene induced by rtEa4-peptide in MDA-MB-231 cells was abolished by inhibitors of PI3K, PKC, Mek1/2, JNK1/2, and p38 MAPK signaling transduction molecules. These results suggested that induction of fibronectin 1 gene expression in MDA-MB-231 cells by rtEa4-peptide may be mediated via PI3K, PKC, Mek1/2, JNK1/2, and p38 MAPK signal transduction molecules.

Animals↗

PubMed2003

Collagen-IV and laminin-1 regulate estrogen receptor alpha expression and function in mouse mammary epithelial cells.

The expression level and functional activity of estrogen receptor alpha is an important determinant of breast physiology and breast cancer treatment. However, it has been difficult to identify the signals that regulate estrogen receptor because cultured mammary epithelial cells generally do not respond to estrogenic signals. Here, we use a combination of two- and three-dimensional culture systems to dissect the extracellular signals that control endogenous estrogen receptor alpha. Its expression was greatly reduced when primary mammary epithelial cells were placed on tissue culture plastic; however, the presence of a reconstituted basement membrane in combination with lactogenic hormones partially prevented this decrease. Estrogen receptor alpha expression in primary mammary fibroblasts was not altered by these culture conditions, indicating that its regulation is cell type specific. Moreover, estrogen receptor-dependent reporter gene expression, as well as estrogen receptor alpha levels, were increased threefold in a functionally normal mammary epithelial cell line when reconstituted basement membrane was added to the medium. This regulatory effect of reconstituted basement membrane was reproduced by two of its components, collagen-IV and laminin-1, and it was blocked by antibodies against alpha2, alpha6 and beta1 integrin subunits. Our results indicate that integrin-mediated response to specific basement membrane components, rather than cell rounding or cell growth arrest induced by reconstituted basement membrane, is critical in the regulation of estrogen receptor alpha expression and function in mammary epithelial cells.

Animals↗

PubMed2002

Alteration of integrin expression relates to malignant progression of human papillomavirus-immortalized esophageal keratinocytes.

To investigate cellular changes related to the malignant progression of keratinocytes, we studied the serum-resistant clones from CHEK-1, a human papillomavirus type 16 E6/E7-immortalized esophageal cell line cultured in a serum-free medium. Established clones exhibited morphologic variety. Slow growing clones presented in cuboidal shapes with tight cellular adhesion and highly expressed alpha2 and alpha6beta4 integrins. Moderately proliferating clones showed loose intercellular adhesion and reduced expression of alpha2 integrin. Spindle-shaped, rapidly proliferating clones with prominent actin stress fibers demonstrated reduced alpha6 and alpha4 integrin expression in addition to alpha2 integrin and showed anchorage-independent growth. Reduced expression of alpha2 integrin was observed between 50 and 100 population doubling lengths (PDLs) during the immortalization of CHEK-1. These results suggest that the reductions of alpha2 and alpha6beta4 integrins are related to changes seen during immortalization and malignant progression.

Actins↗