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Expression of the cyclin-dependent kinase inhibitors (CKIs) has been linked to the inhibition of cellular proliferation and the induction of differentiation. Based on structure function analysis, two distinct families of CDKIs, the INK4 and the Cip/Kip family have been identified. The INK4 family member p16 Ink4 , and the Cip/Kip protein p27 Kip1 have been implicated in normal development of the CNS and cerebellum. Recent studies have suggested a functional inter-dependence between the CKI and the abundance of cyclin D1 in orchestrating growth factor-induced cellular proliferation. The neonatal rat cerebellum undergoes proliferative growth and differentiation, localized to distinct topographical regions and cell types. The cell type and the temporal profile of CKI expression during postnatal cerebellar development had not been described. The current studies determined the specific cerebellar cell types in which the CKIs were expressed during post natal development by co-staining for cell-type specific markers. p16 Ink4a and p27 Kip1 immunostaining was identified in both neurons and glial cells, increasing progressively between postnatal days 6 to 13 into adulthood. By contrast, neuronal and glial cell p21 Cip1 staining was prominent at days 6–11 and decreased thereafter. Cyclin D1 was expressed in the proliferating external granular cells, with occassional staining in the molecular, and internal granular layers. Dual immunostaining demonstrated cyclin D1 within cells expressing CKI (p16 Ink4a , p21 Cip1 ,p27 Kip1 ). Cerebellar cellular growth arrest, induced by protein–calorie malnutrition, inhibited cyclin D1 protein levels without affecting CKI immunostaining suggesting CKI do not mediate the developmental arrest. These results demonstrate that the CKIs are induced by differentiation cues in specific cell types with distinct kinetics in the developing cerebellum in vivo.

Rheumatoid arthritis (RA) is characterized by recruitment of leukocytes from the vasculature into inflamed synovial tissue (ST) and synovial fluid (SF), which depends, in part, upon the continued maintenance of chemotactic stimuli. RANTES is a potent chemoattractant for leukocytes including monocytes and CD45RO+ memory T lymphocytes. The aim of this study was to determine the production, the source, and the function of antigenic RANTES in arthritis. We detected antigenic RANTES in SFs from RA and OA patients (100 +/- 22.7 and 72 +/- 30.7 pg/ml, respectively). CM from RA ST fibroblasts stimulated with interleukin-1beta or tumor necrosis factor-alpha contained significantly more antigenic RANTES than unstimulated CM (452 +/- 181.6 and 581 +/- 200.2 pg/ml, respectively, versus 12 +/- 4.4 pg/ml, P0.05). PHA-stimulated RA SF mononuclear cells secreted 5- to 15-fold more antigenic RANTES than did nonstimulated mononuclear cells, while LPS induced secretion up to 4-fold. We immunolocalized antigenic RANTES to sublining macrophages (28 +/- 3.7 and 8 +/- 2.0% immunopositive cells), perivascular macrophages (56 +/- 6.9 and 19 +/- 3.4%), and synovial lining cells (37 +/- 5.8 and 60 +/- 10.4%) in RA and OA tissue, respectively. Anti-RANTES neutralized 20.2 +/- 1.3% of the RA SF chemotactic activity for normal peripheral blood monocytes (P0.05). These results demonstrate antigenic RANTES in RA and OA ST and SF and identify RANTES as a chemoattractant for monocytes in the RA joint.

Background: The current trend in plastic surgery of the eyelid has taken on increased dependence on anatomical considerations in the marriage of aesthetic and functional ideals. Often, the plastic surgeon performs ptosis and/or septal surgery in conjunction with blepharoplasty. The relationship between eyelid adnexal structures and upper eyelic function is a delicate but critical one. Current anatomical description states that the septum does not reach the superior tarsal border and inserts at a variable level on the levator aponeurosis. Conflicting observations in clinical practice stimulated this study to delineate the septal relationship to surrounding structures. In addtion, this study may help to explain the increased rate of recurrence in ptosis repairs that incorporate plication techniques. Methods: Dissection of four fresh cadaveric upper lid specimens in situ along with hematoxylin and eosin and trichrome stains of harvested eyelid tissue were used to redefine septal anatomy... Clinical case correlations are made to illustrate the significance of the histologic findings. Results: A distinct septal extension was demonstrated arising from the orbital septum and covering preaponeurotic fat and tarsus completely. Histology of the anterior lamellae confirmed the presence of this this fibrous sheet. In vivo assessment of this structure verifies its dynamic role in upper lid function. The clinical ramifications of this anatomical nuance are realized. Conclusions: A septal extension to the ciliary margin of the upper eyelid is established. Suture plication of the septal extension can induce lid elevation, with potential postoperative lid retraction. Intraoperative failure to recognize and distinguish this extension from the aponeurosis proper may lead to the high reported rates of unsuccessful ptosis correction. This refinement of septal anatomy should increase precision and help surgeons avoid complications in advanced blepharoplasty and ptosis surgery.

Leukocyte-endothelial interaction mediated by adhesion molecules may play a role in the ingress of inflammatory cells into the rheumatoid (RA) synovial tissue (ST). A number of these molecules have been shown to be up-regulated in the inflamed compared to normal ST. We studied the distribution of two members of the CD66 carcinoembryonic antigen adhesion molecule family, as well as that of CD31, an antigen structurally related to CD66, on various cell types in the RA compared to osteoarthritic (OA) and normal ST. Immunoperoxidase histochemistry was carried out using monoclonal antibodies to CD66a, CD66b, and CD31. This study was performed on ST from 10 patients with RA, 10 with OA, and 4 normal individuals. CD66a and CD66b were expressed on RA and OA ST myeloid cells but not on normal ST lining cells and interstitial macrophages, suggesting that these antigens may be specific markers of diseased compared to normal ST macrophages (P < 0.05). CD31 was present on more RA and OA than on normal ST macrophages. Also, CD31 was present on most RA, OA, and normal ST endothelial cells. Our results indicate that the expression of CD66a, CD66b, and CD31, members of the immunoglobulin superfamily of adhesion receptors, is up-regulated on cells of myeloid origin in the inflamed compared to normal ST. These results suggest that the CD66 antigens and CD31 may be involved in the adhesive events in the inflamed synovium.

We describe a case of bilateral vocal process lesions in a 65-year-old man. His history was strongly suggestive of vocal process granulomas: previous gastroesophageal reflux, intubation, smoking, and oral squamous cell carcinoma. Medical management with a proton-pump inhibitor, reflux precautions, voice therapy, and adequate hydration yielded no results. Subsequent surgical intervention revealed that he had squamous papillomas. We also provide a brief review of vocal process granulomas and squamous papillomas.

Objective: p68 is an interferon-inducible protein kinase that is believed to be an important factor in the regulation of both viral and cellular protein synthesis. We have previously shown that p68 expression correlates with differentiation in a variety of tumors, including squamous cell carcinoma of the head and neck region. The current study aims to identify the prognostic significance of p68 expression in squamous cell carcinoma of the head and neck. Design: Archival material from a cohort of 75 patients with primary squamous carcinomas of the head and neck was immunostained for p68 with the monoclonal antibody TJ4C4. Overall scores for p68 expression were tabulated based on staining intensity and percentage of immunoreactive tumor cells. Clinical information including tumor grade, stage, site, treatment, disease-free, and total survival was tabulated and compared by p68 expression group. Setting: Veterans Administration Lakeside Medical Center and outpatient clinics (Northwestern University and Veterans Administration Lakeside Medical Center, Chicago, Ill). Patients: Seventy-five consecutive patients with primary squamous cell carcinoma of the head and neck (excluding the esophagus), with tissue blocks available for study, a known primary site, no history of prior carcinoma, and demographic and follow-up information available. Main Outcome Measured: Disease-free and overall survival rates. Results: While there was a wide range of outcomes within each group, as a group, high levels of p68 expression correlated with a lower incidence of recurrent or residual disease and longer disease-free and total survival times compared with groups with lower levels of p68 expression. These differences could not be explained on differences in patient age, tumor grade, and TNM stage. Conclusions: High-level p68 expression is associated with prolonged disease-free and overall survival in a series of patients with squamous cell carcinoma of the head and neck region. Additional study is needed to monitor changes in p68 expression with treatment or tumor progression. (Arch Otolaryngol Head Neck Surg. 1993;119:1142-1147)

Interleukin-1 (IL-1) has protean effects in the pathogenesis of rheumatoid arthritis (RA). These effects include production of prostaglandins and collagenase from rheumatoid fibroblasts as well as upregulation of adhesion molecule expression on these cells. IL-1 can activate monocytes and neutrophils, as well as promote the growth of fibroblasts and endothelial cells. Recently, a novel interleukin-1 receptor antagonist protein (IRAP) has been isolated, purified, cloned, and expressed, which may modulate the effects of IL-1. In this study, we present data demonstrating that macrophages isolated from human RA synovial tissues express both IL-1 and IRAP genes. In addition, RA synovial tissue macrophages and lining cells display IL-1 and IRAP antigenic expression by immunohistochemistry. In contrast, osteoarthritis synovial tissues, as compared to RA, have fewer IL-1 and IRAP-positive macrophages. Thus, the production of IL-1 balanced by IRAP may affect the joint destruction found in these diseases.

Key steps crucial to the process of tumor progression are genomic instability and escape from apoptosis. Nitric oxide and its interrelated reactive intermediates (collectively denoted as NOX) have been implicated in DNA damage and mutational events leading to cancer development, while also being implicated in the inhibition of apoptosis through S-nitrosation of key apoptotic enzymes. The purpose of this study was to explore the interrelationship between NOX-mediated DNA strand breaks (DSBs) and apoptosis in cultured tumor cell lines.

Objective Rheumatoid arthritis (RA) is characterized by infiltration of leukocytes, including monocyte/macrophages, into synovial tissue (ST), but factors mediating the ingress of these cells are poorly understood. Vascular cell adhesion molecule 1 (VCAM-1) plays an important role in adhesion of leukocytes to the vasculature. This study was undertaken to test the hypothesis that soluble VCAM-1 (sVCAM-1) might mediate chemotaxis of monocytes in RA. Methods Chemotaxis assays were performed using a modified Boyden chamber to determine the effects of sVCAM-1 on and the role of very late activation antigen 4 (VLA-4) in peripheral blood (PB) monocyte migration. Synovial fluids (SF) were immunodepleted of sVCAM-1 to identify a role for sVCAM-1 in RA. Immunohistochemistry and flow cytometry analyses were performed to show the expression of VLA-4 in ST, SF, and PB. Tyrosine phosphorylation was studied by Western blot analysis on PB monocyte lysates in the presence of signaling inhibitors. Results Soluble VCAM-1 induced monocyte migration in the nM range, in a concentration-dependent manner. Anti–VLA-4 significantly inhibited sVCAM-1–induced monocyte migration, suggesting that sVCAM-1 acts in part via a VLA-4–dependent mechanism. In RA SF, incubation with anti–VCAM-1 resulted in a reduction in the ability to induce monocyte migration (mean 28%). VLA-4 immunolocalized to RA ST, SF, or PB, monocytes, macrophages, and lymphocytes. Soluble VCAM-1 stimulated tyrosine phosphorylation in monocytes, and pertussis toxin, chelerythrine chloride, and staurosporine significantly reduced sVCAM-1–mediated monocyte chemotaxis, suggesting that signaling pathways via G proteins and protein kinase C are required for sVCAM-1–mediated monocyte migration. Conclusion These results demonstrate a novel function for sVCAM-1 as a monocyte chemotactic agent in RA and suggest a new potential target for modulating monocyte ingress into inflamed RA ST.

Alterations in the stoichiometric balance between members of Bcl-2 and Fas apoptotic pathway could lead to the pathogenesis of systemic lupus erythematosus (SLE). We showed that patients with SLE displayed increased expression in antiapoptotic members of the Bcl-2 and Fas apoptotic pathways in isolated mononuclear cells. Further, mice (Bcl2l11(-/-)Fas(lpr/lpr)) lacking the Bcl-2 pro-apoptotic member, Bim (Bcl2l11(-/-)) and and with an lpr mutation in the gene encoding Fas (Fas(lpr/lpr)) developed severe SLE-like disease by 16 weeks of age unlike Bcl2l11(-/-) or Fas(lpr/lpr) mice. Bcl2l11(-/-)Fas(lpr/lpr) antigen-presenting cells (APCs) were markedly activated, and their numbers were increased in lymphoid tissues and in kidneys, yet numerous TUNEL-positive cells were observed in glomeruli of Bcl2l11(-/-)Fas(lpr/lpr) mice. These data demonstrate that dysregulation of the Bcl-2 or Fas pathways can alter the function of APCs, thereby leading to SLE pathogenesis.

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Additional file of Dysregulated expression of MIG/CXCL9, IP-10/CXCL10 and CXCL16 and their receptors in systemic sclerosis

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During the pathogenesis of rheumatoid arthritis (RA), the synovial fibroblasts increase in number and produce proinflammatory cytokines and matrix metalloproteinases (MMPs) that function to promote inflammation and joint destruction. Recent investigations have suggested that cell cycle activity and inflammation may be linked. However, little is known about the mechanisms responsible for the coordinate regulation of proliferation and the expression of proinflammatory molecules in RA synovial fibroblasts. Here, we demonstrate a 50 ± 10% decrease in the expression of p21, a cell cycle inhibitor, in the synovial fibroblast population from RA compared with osteoarthritis (OA) synovial tissue. Moreover, p21 positivity in the synovial fibroblasts inversely correlates with medium synovial lining thickness (r = −0.76; p < 0.02). The expression of p21 is also reduced in isolated RA synovial fibroblasts compared with OA synovial fibroblasts. Adenovirus-mediated delivery of p21 (Ad-p21) arrests both RA and OA synovial fibroblasts in the G0/G1 phase of the cell cycle without inducing cytotoxicity. However, the spontaneous production of IL-6 and MMP-1 is suppressed only in the Ad-p21-infected RA synovial fibroblasts, indicating a novel role for p21 in RA. Analyses of p21-deficient mouse synovial fibroblasts reveal a 100-fold increase in IL-6 protein and enhance IL-6 and MMP-3 mRNA. Restoration of p21, but not overexpression of Rb, which also induces G0/G1 cell cycle arrest, decreases IL-6 synthesis in p21-null synovial fibroblasts. Furthermore, in RA synovial fibroblasts the ectopic expression of p21 reduces activation of the AP-1 transcription factor. Additionally, p21-null synovial fibroblasts display enhanced activation of AP-1 compared with wild-type synovial fibroblasts. These data suggest that alterations in p21 expression may activate AP-1 leading to enhanced proinflammatory cytokine and MMP production and development of autoimmune disease.

Additional file of Dysregulated expression of MIG/CXCL9, IP-10/CXCL10 and CXCL16 and their receptors in systemic sclerosis

Additional file of Dysregulated expression of MIG/CXCL9, IP-10/CXCL10 and CXCL16 and their receptors in systemic sclerosis

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Additional file of Dysregulated expression of MIG/CXCL9, IP-10/CXCL10 and CXCL16 and their receptors in systemic sclerosis

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Additional file of Dysregulated expression of MIG/CXCL9, IP-10/CXCL10 and CXCL16 and their receptors in systemic sclerosis

Mcl-1 is a Bcl-2-family, antiapoptotic molecule that is critical for the survival of T and B lymphocytes and macrophages; however, its role in nonhemopoietic cells remains to be fully elucidated. The current study focuses on the role of Mcl-1 in rheumatoid arthritis (RA). Mcl-1 was strongly expressed in the synovial lining and was increased in the sublining fibroblasts of patients with RA, compared with control synovial tissue. The expression of Mcl-1 in sublining fibroblasts correlated with the degree of inflammation and TNF-α, and IL-1β treatment of cultured synovial fibroblasts resulted in the increased expression of Mcl-1 at the mRNA and protein levels. Mcl-1 was critical for the survival of RA synovial fibroblasts, because the forced reduction of Mcl-1 using a Mcl-1 antisense-expressing adenoviral vector induced apoptotic cell death, which was mediated through Bax, Bak, and Bim. These observations document a critical role for Mcl-1 in protecting against apoptosis in RA and suggest that Mc1–1 is a potential therapeutic target in this disease.

Background Inhibitor of DNA binding 1 (Id1) is a nuclear protein containing a basic helix-loop-helix (bHLH) domain that regulates cell growth by selective binding and prevention of gene transcription. Sources of Id1 production in rheumatoid arthritis synovial tissue (RA ST) and its range of functional effects in RA remain to be clarified. Methods We analyzed Id1 produced from synovial fibroblasts and endothelial cells (ECs) with histology and real-time polymerase chain reaction (RT-PCR). Fibroblast supernatants subjected to differential centrifugation to isolate and purify exosomes were measured for Id1 by enzyme-linked immunosorbent assay (ELISA). Western blotting of Id1-stimulated ECs was performed to determine the kinetics of intracellular protein phosphorylation. EC intracellular signaling pathways induced by Id1 were subsequently targeted with silencing RNA (siRNA) for angiogenesis inhibition. Results By PCR and histologic analysis, we found that the primary source of Id1 in STs is from activated fibroblasts that correlate with inflammatory scores in human RA ST and in joints from K/BxN serum-induced mice. Normal (NL) and RA synovial fibroblasts increase Id1 production with stimulation by transforming growth factor beta (TGF-β). Most of the Id1 released by RA synovial fibroblasts is contained within exosomes. Endothelial progenitor cells (EPCs) and human dermal microvascular ECs (HMVECs) activate the Jnk signaling pathway in response to Id1, and Jnk siRNA reverses Id1-induced HMVEC vessel formation in Matrigel plugs in vivo. Conclusions Id1 is a pleotropic molecule affecting angiogenesis, vasculogenesis, and fibrosis. Our data shows that Id1 is not only an important nuclear protein, but also can be released from fibroblasts via exosomes. The ability of extracellular Id1 to activate signaling pathways expands the role of Id1 in the orchestration of tissue inflammation.

Introduction: Systemic sclerosis (SSc) is characterized by fibrosis and microvascular abnormalities including dysregulated angiogenesis. Chemokines, in addition to their chemoattractant properties, have the ability to modulate angiogenesis. Chemokines lacking the enzyme-linked receptor (ELR) motif, such as monokine induced by interferon-g (IFN-g) (MIG/CXCL9) and IFN-inducible protein 10 (IP-10/CXCL10), inhibit angiogenesis by binding CXCR3. In addition, CXCL16 promotes angiogenesis by binding its unique receptor CXCR6. In this study, we determined the expression of these chemokines and receptors in SSc skin and serum. Methods: Immunohistology and enzyme-linked immunosorbent assays (ELISAs) were used to determine chemokine and chemokine receptor expression in the skin and serum, respectively, of SSc and normal patients. Endothelial cells (ECs) were isolated from SSc skin biopsies and chemokine and chemokine receptor expression was determined by quantitative PCR and immunofluorescence staining. Results: Antiangiogenic IP-10/CXCL10 and MIG/CXCL9 were elevated in SSc serum and highly expressed in SSc skin. However, CXCR3, the receptor for these chemokines, was decreased on ECs in SSc vs. normal skin. CXCL16 was elevated in SSc serum and increased in SSc patients with early disease, pulmonary arterial hypertension, and those that died during the 36 months of the study. In addition, its receptor CXCR6 was overexpressed on ECs in SSc skin. At the mRNA and protein levels, CXCR3 was decreased while CXCR6 was increased on SSc ECs vs. human microvascular endothelial cells (HMVECs). Conclusions: These results show that while the expression of MIG/CXCL9 and IP-10/CXCL10 are elevated in SSc serum, the expression of CXCR3 is downregulated on SSc dermal ECs. In contrast, CXCL16 and CXCR6 are elevated in SSc serum and on SSc dermal ECs, respectively. In all, these findings suggest angiogenic chemokine receptor expression is likely regulated in an effort to promote angiogenesis in SSc skin.

The focal adhesion kinase (FAK) family kinases, including FAK and proline-rich kinase 2 (Pyk)2, are the predominant mediators of integrin alphavbeta3 signaling events that play an important role in cell adhesion, osteoclast pathology, and angiogenesis, all processes important in rheumatoid arthritis (RA). Using immunohistochemical and western blot analysis, we studied the distribution of phospho (p)FAK, pPyk2, pSrc, pPaxillin and pPLCgamma in the synovial tissue (ST) from patients with RA, osteoarthritis (OA) and normal donors (NDs) as well as in RA ST fibroblasts and peripheral blood differentiated macrophages (PB MPhis) treated with tumor necrosis factor-alpha (TNFalpha) or interleukin-1beta (IL1beta). RA and OA STs showed a greater percentage of pFAK on lining cells and MPhis compared with ND ST. RA ST fibroblasts expressed pFAK at baseline, which increased with TNFalpha or IL1beta stimulation. Pyk2 and Src were phosphorylated more on RA versus OA and ND lining cells and MPhis. pPyk2 was expressed on RA ST fibrobasts but not in MPhis at baseline, however it was upregulated upon TNFalpha or IL1beta activation in both cell types. pSrc was expressed in RA ST fibroblasts and MPhis at baseline and was further increased by TNFalpha or IL1beta stimulation. pPaxillin and pPLCgamma were upregulated in RA versus OA and ND lining cells and sublining MPhis. Activation of the FAK family signaling cascade on RA and OA lining cells may be responsible for cell adhesion and migration into the diseased STs. Therapies targeting this novel signaling pathway may be beneficial in RA.