Alterations In Cell Adhesion Molecules Research Articles

Expression of p120 - catenin in oral squamous cell carcinoma and apparently normal mucosa adjacent to oral squamous cell carcinoma.

An essential molecular occurrence in carcinogenesis that can lead to invasion and migration, predisposing cells to malignant transformation, involves alterations in cell adhesion molecules, such as p120 catenin. The destabilization of E-cadherin, caused by the loss or phosphorylation of p120 catenin (p120), regulates cadherin stability and turnover, impacting cell adhesiveness and migratory capacity. Consequently, p120 is associated with the invasiveness and progression of various human epithelial tumor types, including Oral Squamous Cell Carcinomas (OSCC). The present study aimed to assess and establish a correlation between the expression of p120 antibody in OSCC and Apparently Normal Mucosa Adjacent to OSCC (ANMAOSCC). The immunoexpression of p120 in 300 selected cases was categorized into two groups: OSCC (n = 150) and ANMAOSCC (n = 150). Two 4µm-thick tissue sections from the selected blocks were prepared. One section was stained with Hematoxylin and Eosin, while the other underwent immunohistochemical (IHC) staining using anti-p120 catenin antibody (clone No. EP66; Catalog No. PR062; PathnSitu, Wayne, PA, USA). The analysis of p120 immunoexpression included parameters such as intensity, percentage, and the location of staining. In OSCC, over 80% of cases expressed p120, with only 16% exhibiting loss of expression. In ANMAOSCC, all cells maintained p120 expression. In OSCC, p120 was predominantly localized to the membrane and cytoplasm in 76%, while in ANMAOSCC, over 90% showed membrane localization. Regarding positivity, only 19% of OSCC cases reported positivity in >50% of cells, compared to 64.7% in ANMAOSCC. The extent of staining in ANMAOSCC was observed up to the granular layer (45%) and corneal layer (19%). The atypical staining pattern of p120 may indicate a loss of adhesion and could serve as a marker for identifying the malignant potential of ANMAOSCC and the aggressiveness of OSCC. Key words:Oral Squamous Cell Carcinoma, P120 Catenin, Cell Adhesion Molecules, Gene Expression Regulation.

PCF11, a Novel CD44-Downstream Transcriptional Target, Linking Its 3'-End Polyadenylation Function to Tumor Cell Metastasis.

Breast Cancer (BC) is the most common and the major health issue in women worldwide. Metastasis, a multistep process, is the worst aspect of cancer and tumor cell invasion is the defining step. Tumor cell invasion requires cell adhesion molecules (CAMs), and alterations in CAMs is considered as an initiating event in metastasis. Among CAMs, CD44 is a large family of more than 100 isoform, and its precise function was initially controversial in BC. Therefore, we have previously established a (Tet)-off inducible expression system of CD44 in MCF-7 primary BC cell line, and showed that CD44 promoted BC invasion/metastasis both in vitro and in vivo. A microarray gene expression profiling revealed more than 200 CD44-downstream potential transcriptional target genes, mediating its role in BC cell invasion and metastasis. Among these CD44-target genes, the Pre-mRNA cleavage complex 2 protein (PCF11) was upregulated upon the activation of CD44 by its major ligand hyaluronan (HA); This prompted us to hypothesize PCF11 as a potential novel transcriptional target of CD44-promoted BC cell invasion and metastasis. A large body of evidence from the literature supports our hypothesis that CD44 might regulate PCF11 via MAPK/ERK pathway. This review aims to discuss these findings from the literature that support our hypothesis, and further provide possible mechanisms linking CD44-promoted cell invasion through regulation of its potential target PCF11.

Age-dependent increase in Thy-1 protein in the rat supraoptic nucleus.

Mature mammalian CNS neurons often do not recover successfully following injury. To this point, unilateral lesion of the hypothalamo-neurohypophysial tract results in collateral sprouting from uninjured axons of the supraoptic nucleus (SON) in 35-day-old but not in 125-day-old rats. Thus, it appears that there are age-related changes within the SON that preclude the older rat from recovering following axotomy. We hypothesize that the intrinsic capacity for axon reorganization may depend, in part, on age-related alterations in cell adhesion molecules that allow normal astrocyte-neuron interactions in the SON. In support of our hypothesis, numerous reports have shown that Thy-1 is increased in neurons at the cessation of axon outgrowth. Therefore, we compared protein levels of Thy-1 and the Thy-1 interacting integrin subunits, alpha-v (αv), beta-3 (ß3), and beta-5 (ß5), in 35- and 125-day-old SON using western blot analysis. Our results demonstrated that there was significantly more Thy-1 protein in the 125-day-old SON compared to 35-day-old SON, but no change in the protein levels of the integrin subunits. Furthermore, we localized Thy-1-, αv integrin-, ß3 integrin-, and ß5 integrin-immunoreactivity to both neurons and astrocytes in the SON. Altogether, our results suggest that the observed increase in Thy-1 protein levels in the SON with age may contribute to an environment that prevents collateral axonal sprouting in the SON of the 125-day-old rat.

The CXCL12-CXCR4/CXCR7 axis as a mechanism of immune resistance in gastrointestinal malignancies.

Single agent checkpoint inhibitor therapy has not been effective for most gastrointestinal solid tumors, but combination therapy with drugs targeting additional immunosuppressive pathways is being attempted. One such pathway, the CXCL12-CXCR4/CXCR7 chemokine axis, has attracted attention due to its effects on tumor cell survival and metastasis as well as immune cell migration. CXCL12 is a small protein that functions in normal hematopoietic stem cell homing in addition to repair of damaged tissue. Binding of CXCL12 to CXCR4 leads to activation of G protein signaling kinases such as P13K/mTOR and MEK/ERK while binding to CXCR7 leads to β-arrestin mediated signaling. While some gastric and colorectal carcinoma cells have been shown to make CXCL12, the primary source in pancreatic cancer and peritoneal metastases is cancer-associated fibroblasts. Binding of CXCL12 to CXCR4 and CXCR7 on tumor cells leads to anti-apoptotic signaling through Bcl-2 and survivin upregulation, as well as promotion of the epithelial-to-mesechymal transition through the Rho-ROCK pathway and alterations in cell adhesion molecules. High levels of CXCL12 seen in the bone marrow, liver, and spleen could partially explain why these are popular sites of metastases for many tumors. CXCL12 is a chemoattractant for lymphocytes at lower levels, but becomes chemorepellant at higher levels; it is unclear exactly what gradient exists in the tumor microenvironment and how this influences tumor-infiltrating lymphocytes. AMD3100 (Plerixafor or Mozobil) is a small molecule CXCR4 antagonist and is the most frequently used drug targeting the CXCL12-CXCR4/CXCR7 axis in clinical trials for gastrointestinal solid tumors currently. Other small molecules and monoclonal antibodies against CXCR4 are being trialed. Further understanding of the CXCL12- CXCR4/CXCR7 chemokine axis in the tumor microenvironment will allow more effective targeting of this pathway in combination immunotherapy.

Abstract 66: p120 catenin: A novel regulator of PanIN epithelial cell delamination in preinvasive pancreatic cancer

Abstract Pancreatic cancer is among the deadliest human malignancies ranking 4th in the United States for cancer-related deaths among both men and women. Due to the invasive nature of pancreatic cancer, metastasis to the lymphatic system and distant organs is a major contributor to pancreatic cancer-related death. Genetic alterations in cell adhesion molecules contribute to human disease including developmentally related syndromes and cancer. In a sequencing study of 24 primary pancreatic tumor exomes published by the Hopkins pancreatic cancer team in 2008, 79% of tumors had at least one mutation in a homophilic cell adhesion molecule, and this class of molecules was named as one of the twelve core signaling pathways in pancreatic cancer. Among this class of cell adhesion molecules are adherens junctions. Mislocalization of the adherens protein p120 catenin has been identified in almost all of the major types of human carcinomas including pancreatic cancer. An accumulating body of evidence has identified p120 catenin as a prognostic marker in pancreatic cancer. Based on relevant literature, we hypothesize that misexpression and mislocalization of p120 catenin in pancreatic cancer is pathologic in the progression of this deadly disease. To test this hypothesis, we have ablated p120 catenin in the KCiMist1 mouse model of pancreatic cancer. The KCiMist1 mouse model activates oncogenic Kras in adult pancreatic acinar cells and displays the preinvasive PanIN 1 - PanIN 3 lesions in a manner that faithfully recapitulates the human disease. Homozygous deletion of p120 catenin in this model resulted in an almost complete replacement of acinar cells by acinar to ductal metaplastic lesions, accelerated PanIN formation, and stromal infiltration at 1 month. At 2 months, the stromal infiltrate persists, and we see considerable evidence of fibrosis and fatty deposition in the pancreas, which are pathologic features of pancreatitis. We used the KCiMist1Gp120f/f model to trace the lineage of acinar cells undergoing Kras activation and p120 catenin excision, and observed a marked increase in isolated GFP+ Ecadherin+ cells located in the extensive stroma at 1 and 2 months suggesting that p120 catenin normally restrains PanIN epithelial cell delamination. We have begun to study potential mechanisms for this delamination phenotype including epithelial-mesenchymal transition (EMT) and non-EMT based mechanisms. Research suggests that EMT is a contributing factor to the development of drug resistance, which makes EMT a promising target for the development of future therapies that reduce invasion and drug resistance leading to better prognosis for patients with pancreatic cancer. Our preliminary findings suggest that the KCiMist1Gp120f/f mouse model represents a valuable tool to study both EMT and non-EMT based mechanisms for PanIN epithelial cell delamination. Citation Format: Audrey M. Hendley, Jennifer M. Bailey, Janivette Alsina, Christine Iacobuzio-Donahue, Anirban Maitra, Albert Reynolds, Steven D. Leach. p120 catenin: A novel regulator of PanIN epithelial cell delamination in preinvasive pancreatic cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 66. doi:10.1158/1538-7445.AM2014-66

WAVE2 Protein Complex Coupled to Membrane and Microtubules

E-cadherin is one of the key molecules in the formation of cell-cell adhesion and interacts intracellularly with a group of proteins collectively named catenins, through which the E-cadherin-catenin complex is anchored to actin-based cytoskeletal components. Although cell-cell adhesion is often disrupted in cancer cells by either genetic or epigenetic alterations in cell adhesion molecules, disruption of cell-cell adhesion alone seems to be insufficient for the induction of cancer cell migration and invasion. A small GTP-binding protein, Rac1, induces the specific cellular protrusions lamellipodia via WAVE2, a member of WASP/WAVE family of the actin cytoskeletal regulatory proteins. Biochemical and pharmacological investigations have revealed that WAVE2 interacts with many proteins that regulate microtubule growth, actin assembly, and membrane targeting of proteins, all of which are necessary for directional cell migration through lamellipodia formation. These findings might have important implications for the development of effective therapeutic agents against cancer cell migration and invasion.

The cytologic criteria of malignancy

Cytology and cell biology are two separate fields that share a focus on cancer. Cancer is still diagnosed based on morphology, and surprisingly little is known about the molecular basis of the defining structural features. Cytology uses the smallest possible biopsy for diagnosis by reducing morphologic "criteria of malignancy" to the smallest scale. To begin to develop common ground, members of the American Society of Cytopathology Cell Biology Liaison Working Group classify some of the "criteria of malignancy" and review their relation to current cell biology concepts. The criteria of malignancy are extremely varied, apparently reflecting many different pathophysiologies in specific microenvironments. Criteria in Group 1 comprise tissue-level alterations that appear to relate to resistance to anoikis, alterations in cell adhesion molecules, and loss of apical-basal polarity. Criteria in Group 2 reflect genetic instability, including chromosomal and possibly epigenetic instability. Criteria in Groups 3 are subcellular structural changes involving cytoplasmic components, nuclear lamina, chromatin and nucleoli that cannot be accounted for by genetic instability. Some distinct criteria in Group 3 are known to be induced by cancer genes, but their precise structural basis remains obscure. The criteria of malignancy are not closely related to the histogenetic classification of cancers, and they appear to provide an alternative, biologically relevant framework for establishing common ground between cytologists and cell biologists. To understand the criteria of malignancy at a molecular level would improve diagnosis, and likely point to novel cell physiologies that are not encompassed by current cell biology concepts.

Alterations in cell adhesion molecules and other biomarkers of cardiovascular disease in patients with metabolic syndrome

Metabolic syndrome is considered a hyperinsulinemic and inflammatory state closely associated to endothelial dysfunction causing an increased incidence of ischemic cardiovascular events and high mortality. The main objective of the present study was to determine whether leukocitary and soluble cell adhesion molecules were altered in patients with metabolic syndrome in comparison with control subjects. Cell adhesion molecules, mainly of leukocitary location, have been not previously evaluated in specifically designed cross-sectional studies involving male patients with metabolic syndrome. Moreover, other circulating markers of different candidate atherogenic risk parameters were also studied and the potential existence of a progressive relation between the number of metabolic syndrome components and the above mentioned biomarkers was analyzed. Thirty one male patients with metabolic syndrome (ATPIII definition) and 56 male control subjects were studied. We evaluated different markers of insulin resistance, inflammation and atherosclerosis, as well as protective factors. Patients with metabolic syndrome showed (a) hypoadiponectinemia (4551 ± 2302 ng/ml vs. 5865 ± 2548 ng/ml, respectively; p < 0.05), (b) an atherogenic lipid and lipoprotein profile, (c) altered HDL chemical composition accompanied by higher cholesteryl ester-triglyceride interchange carried out by CETP, (d) diminished Lp-PLA 2 activity (6.5 ± 1.9 vs. 7.3 ± 2.2, p < 0.05, respectively), antioxidant enzyme related with LDL oxidation, which was positively associated with QUICKI and negatively with VCAM-1 and lymphocyte CD18, and (e) high soluble (VCAM-1: 17 ± 5 vs. 13 ± 4 ng/ml, respectively; p < 0.0005) and leukocyte adhesion molecule expression (monocyte CD54: 52 ± 15 vs. 45 ± 12 arbitrary units, respectively; p < 0.0005; and lymphocyte CD49d: 312 ± 56 vs. 284 ± 64 arbitrary units, respectively; p < 0.05). The increment in leukocyte and soluble cell adhesion molecules, crucial for leukocyte interaction with the endothelium and migration into the artery wall, in combination with the other disorders described above reinforce the presence of a clinical status with high propensity to type 2 diabetes and atherosclerotic cardiovascular disease.

Apoptosis and angiogenesis in endometriosis: relationship to development and progression

Objective: Endometriosis is one of the most frequent diseases in gynecology. However, the pathogenesis and mechanisms involved in the development and progression of endometriosis is still not clear. Based on the enhanced survival of endometriotic tissue, there could be interplay between apoptosis, angiogenesis and alterations in cell adhesion molecules. To determine the contribution of apoptosis and angiogenesis to the development and progression of endometriosis and to explore how spontaneous apoptosis correlates with angiogenesis in this disease entity.

Atherosclerosis and Cancer

Recently, a series of shared molecular pathways have emerged that have in common a significant role in the pathogenesis and progression of both atherosclerosis and cancer. Oxidative stress and the cellular damage that results from it have been implicated in a wide variety of disease processes including atherogenesis and neoplasia. Toxic metabolites produced by cigarette smoking and increased dietary fat intake are implicated in the pathogenesis of both diseases. It has been hypothesized that atherosclerosis may begin when an injury or infection mutates or transforms a single arterial smooth muscle cell in the progenitor of a proliferative clone similar to the most widely held theory of carcinogenesis. Cell proliferation regulatory pathways including genes involved in the GIS checkpoint (p53, pRb, p15, p16, and cyclins A, D, E, and cdk 2,4) have been associated with plaque progression, stenosis and restenosis after angioplasty as well as in cancer progression. Alterations in cell adhesion molecules (integrins, cadherin-catenins) have been linked to plaque formation and thrombosis as well as to tumor invasion and metastasis. Altered expression of proteases associated with thrombolysis has been implicated in atherosclerotic plaque expansion and hemorrhage and in the invasion and metastasis of malignancy. Ligand-growth factor receptor interactions (tyrosine kinases) have been associated with early atherosclerotic lesions as well as cancer development and spread. Nuclear transcription factors such as NFkappaB have been associated with progression of both diseases. Angiogenesis modulators have recently been linked to plaque expansion and restenosis of atherosclerotic lesions as well as local and metastatic tumor expansion. Common disease treatments, such as the use of growth factor inhibitors and radiation treatment, established anticancer treatments, were recently introduced into atherosclerosis therapeutic strategies to prevent restenosis after angioplasty and endarterectomy. In conclusion, a series of molecular pathways of disease development and progression common to atherosclerosis and cancer support that the world's two most common diseases are far more closely aligned than previously believed and that emerging anti-inflammatory and antiproliferative therapeutic strategies may ultimately be efficacious in both conditions.

Immunocytochemical study of retinal diode laser photocoagulation in the rat.

To determine the nature of the cellular infiltrate, alterations in cell adhesion molecules, and MHC II antigen expression in the rat retina following diode laser retinal photocoagulation. 20 normal Lister rats underwent diode laser photocoagulation of the retina. Frozen sections from eyes enucleated at 0, 1, 5, 13, and 33 days post laser were examined for T cells (R7.3), CD4 T cells (W3/25), activated CD4 T cells (OX-40), CD8 T cells (OX-8), B cells (OX-33), and macrophages (OX-42), MHC II antigen (OX-6), and E-Selectin-1, VCAM-1, and ICAM-1. Retinal diode laser photocoagulation stimulated a wound healing response in the outer retina and choroid. The cellular infiltrate included macrophages and activated CD4 T cells at 13 and 33 days post laser. Glial cells in the inner plexiform and inner nuclear layers expressed MHC II antigen at 24 hours only. ICAM-1 antigen was induced in RPE cells and in Muller cells in the inner retina at all time intervals post laser and intense staining for ICAM-1 was present around intraretinal migrated cells at 13 and 33 days post laser. VCAM-1 antigen expression was induced in the choroidal vascular endothelium and RPE at 13 and 33 days after laser as was E-Selectin-1 antigen expression which was also evident focally at the external limiting membrane in association with migrated cells adjacent to the burn. These results suggest that alterations in cell adhesion molecules may regulate the migration and activation of retinal pigment epithelium, macrophages and CD4 T cells at the outer blood-retinal barrier and choroid following diode laser photocoagulation of the normal Lister rat retina.

Comparison of cell adhesion molecule expression between glioblastoma multiforme and autologous normal brain tissue

We investigated glioblastoma multiforme (GBM) for a pattern of consistent alterations in cell adhesion molecules (CAM) expression that might distinguish tumor from normal autologous brain tissue. We used frozen section immunohistochemistry with anti-CAM and computerized image analysis to quantify staining intensity which we expressed as relative intensity units (RIU). Our results showed that normal brain tissue generally did not express α 1 β 1, intercellular CAM-1 (ICAM-1), and sialylated Lewis x, slightly expressed α 2, α 4, α 5, α 6 β 1, α v β 3, lymphocyte function-associated antigen-3 (LFA-3), Lewis x, sialylated LewisLewis x, had a good expression of α 3 β 1 rmand CD44, and strongly expressed neural CAM (NCAM). GBM expressed α 1, α, 3 α 5, α 6 β 1, α v β 3, ICAM-1, LFA-3, CD44, Lewis x, sialylated Lewis x, and sialylated LewisLewis x significantly higher (2-11-fold RIU) than normal brain tissue. ICAM-1 and LFA-3 were the most distinctive markers of GBM. The small blood vessel endothelial cells of the normal brain and the GBM showed a few differences. The tumor endothelium expression of α 2 β 1, α 4 β 1, and LFA-3 RIU appeared twice higher than in normal endothelium and α 6 β 1 showed an average of 40% RIU decrease in comparison to normal. These results show that the expression of several CAM is consistently altered in GBM and its microvasculature when compared with autologous normal brain tissue.

Expression of Retrovirally Transduced IL-1 α in IL-6-Dependent B Cells: A Murine Model of Aggressive Multiple Myeloma

Retroviral-mediated gene transfer was employed to introduce an IL-1 alpha cDNA into an IL-6-dependent murine B-cell line. Bone marrow metastases and bone lesions were frequently observed following intravenous injection of these B cells into syngeneic mice. Because the retroviral vector also contained the neomycin phosphotransferase gene, metastatic cells could be easily recovered from bone marrow by addition of G418 to the culture medium. Interestingly, the metastatic B cells were found to retain their IL-6 dependency through several transplant generations. By comparison, intravenous injection of autonomously-growing B-cell lines generated in vitro by retroviral introduction of an IL-6 cDNA rarely resulted in bone marrow metastases. These results demonstrate that abrogation of growth factor dependency is neither necessary nor sufficient for the in vivo growth and dissemination of tumor cells in this experimental system. It is proposed that the increased metastasis of the IL-1 alpha-producing B-cells to bone marrow is due to alterations in cell adhesion molecules. The B-cell bone marrow metastasis model described here may be useful for studies of bone marrow homing and for evaluation of therapeutic regimens for multiple myeloma.