Cortactin expression in a Norwegian cohort of human papilloma virus negative oral squamous cell carcinomas of the mobile tongue.

Oral squamous cell carcinoma of the tongue (OTSCC) is the most common malignancy among oral squamous cell carcinomas and is frequently associated with an unfavorable prognosis. Local spread and distant metastasis are important causes of poor prognosis in OTSCC. Cortactin amplification and overexpression, a common molecular alteration in oral squamous cell carcinomas, have been linked to invasion and metastasis of tumor cells. However, the intra-tumor expression pattern and prognostic significance of cortactin in human papillomavirus (HPV) negative OTSCC is not fully investigated. Immunohistochemical analysis using tissue microarray consisting of formalin-fixed and paraffin-embedded HPV negative OTSCC (n = 123) specimens showed overexpression of cortactin at tissue cores from invading fronts as compared to the corresponding center cores. High overall cortactin expression was found to be associated with advanced (larger) tumor size and the occurrence of distance metastasis. Kaplan-Meier survival analysis showed that patients with high overall cortactin expression were associated with reduced 5-year survival. Multivariate Cox regression analysis identified high cortactin expression to be an independent prognostic factor in OTSCC. Additionally, siRNA-mediated silencing of cortactin was found to suppress the proliferative and invasive abilities of OTSCC cells in an organotypic co-culture model. Overexpression of cortactin is a promising prognostic marker in HPV-negative OTSCC.

The Regulatory Role of the Oral Commensal Streptococcus mitis on Human Monocytes.

Streptococcus mitis colonizes all niches of the human oral cavity from early infancy and throughout life. Monocytes patrol blood vessels, lymphoid and non-lymphoid tissues and migrate into infected tissue where they participate in the inflammatory cascade and immune regulation. Here, we studied the effect of S. mitis on monocytes. Transcriptome analysis of monocytes exposed to S. mitis (SmMo) revealed increased transcription of chemotactic factors (CCL2, CCL3, CCL20, CXCL1, CXCL2) and cytokines (IL1A, IL1B, IL6, IL23, IL36G, TNF), indicating that S. mitis may trigger recruitment of leucocytes and initiate inflammation. Increased transcription in SmMo of IL1B, IL6 and IL23 indicated that S. mitis may participate in the induction of Th17 responses and agreed with our earlier findings of S. mitis-mediated memory Th17 reactivity. Furthermore, S. mitis inhibited tetanus toxoid-specific CD4 T cell proliferation. This can be due to the increased secretion of IL-10 and expression of PD-L1 that was observed in SmMo. PGE2 can modulate IL-10 and PD-L1 expression, concomitant with that of CCR7, IL-12 and IL-23 that also were changed. This, along with increased SmMo transcription of PTGS2 (COX2) and PTGER4 (EP4), pointed to a role of PGE2. Measurement of PGE2 secretion by SmMo showed indeed a marked increase, and chemical inhibition of PGE2 production lowered the PD-L1 expression on SmMo. In conclusion, our findings show that S. mitis may trigger immune modulation by recruiting immune cells to the site of infection, while at the same time dampening the severity of the response through expression of IL-10, PGE2 and PD-L1.

The short form of TSLP is constitutively translated in human keratinocytes and has characteristics of an antimicrobial peptide.

Thymic stromal lymphopoietin (TSLP) has multifaceted immunological functions ranging from maintenance of tolerance to induction of disease. Two human transcript variants of TSLP are described: a long form (variant 1; lfTSLP) consisting of four exons and an alternative, short form (variant 2; sfTSLP) that lacks two exons compared with variant 1. SfTSLP has not been described at the protein level or functionally studied. Here, we demonstrate that the human sfTSLP is the predominant form of TSLP, constitutively expressed at the mRNA and protein level in keratinocytes of oral mucosa and skin and in salivary glands, is released in saliva, and is not regulated in the same manner as the long form. Compared with lfTSLP, sfTSLP exhibits a markedly stronger antibacterial activity. Synthetic sfTSLP did not activate signal transducer and activator of transcription 5 (STAT5) signaling in CD1c(+) dendritic cells nor interfered with STAT5 activation by lfTSLP. SfTSLP may, therefore, act as an antimicrobial peptide in the oral cavity and on the skin to create a defense barrier that aids in the control of both commensal and pathogenic microbes. The results show that the two translational products of the TSLP gene have a different expression and different biological properties, and emphasize the importance of analyzing the two TSLP isoforms separately.

Trefoil factor family 3 expression in the oral cavity.

This study examined the expression, in oral keratinocytes and in the major and minor salivary glands, of Trefoil factor family 3 (TFF3) peptide. Trefoil factor family 3 messenger RNA (mRNA) and peptide were detected in cultures of normal oral keratinocytes by quantitative real-time polymerase chain reaction (PCR) and western blotting, respectively. Trefoil factor family 3 was found, by immunohistochemical analyses, to be expressed in the basal layers of the oral mucosal epithelium. In salivary glands, immunohistochemical staining showed that TFF3 peptide expression was strongest in the mucous acini of the submandibular and the small salivary glands. Serous cells in the same glands showed weak staining. In the parotid gland, many serous acini showed weak positive staining, while other areas did not. In all glands examined, the intercalated, striated, and collecting ducts were moderately TFF3-positive. Double immunostaining confirmed that mucous (MUC5B positive) cells were moderately or strongly positive for TFF3 and that some serous (MUC7 positive) cells showed restricted TFF3 expression, mostly in a granular pattern. The prevalence of the TFF3 peptide in the salivary secretions of healthy volunteers was detected by western blotting of saliva from minor salivary glands (four of five) and the parotid gland (one of five) and of mixed submandibular/sublingual saliva (five of five). In conclusion, the submandibular and small salivary glands appear to be the major producers of oral TFF3, but duct cells of all glands and keratinocytes of the oral mucosa may also contribute as sources of TFF3 in the oral cavity.

Matrix metalloproteinases and their inhibitors in gingival mast cells in persons with and without human immunodeficiency virus infection.

BACKGROUND: Mast cells are a prominent cell type in the gingival infiltrate in periodontitis. In this study we examined the expression by gingival mast cells of matrix metalloproteinases, MMP-1, MMP-2, MMP-8 and the tissue inhibitors of metalloproteinases, TIMP-1 and TIMP-2. METHODS: Gingival specimens from 12 human immunodeficiency virus-negative (HIV-) and 15 HIV-positive (HIV+) patients with chronic marginal periodontitis (CMP), and from 10 HIV- and four HIV+ controls with clinically healthy gingiva (HG) were examined after double immunofluorescence staining for mast cell tryptase, combined with antibodies for MMP-1, MMP-2, MMP-8 or their inhibitors TIMP-1 and TIMP-2. RESULTS: In the HIV+CMP, HIV+HG and HIV-CMP groups, all mast cells expressed MMP-1 and MMP-8, whereas a smaller proportion (40-60%) in the HIV-HG controls displayed such staining. The former groups also displayed a significantly higher proportion (39-64%) of mast cells expressing MMP-2 as compared with the HIV-HG group (21-31%). All groups displayed similar proportions of TIMP-1 expressing mast cells (86-100%), whereas significantly increased proportions of TIMP-2+ mast cells were seen in the HIV+CMP, HIV+HG and HIV-CMP groups (18-25%) as compared with the HIV-HG group (8-13%). Mast cells were the cell type that most prominently expressed MMP-1 and MMP-8. MMP-2 expression was also strong in mast cells, but was also similarly expressed in other cell types. CONCLUSION: The chronically inflamed periodontal lesions in the present study appeared with little evidence of mast cell degranulation. The results show, however, that mast cells in inflamed gingiva have the potential to degrade extracellular matrix if appropriately triggered.

Liver metastasis of cancer facilitated by chemokine receptor CCR6.

When injected subcutaneously, mouse plasmacytoma (MOPC315) grew rapidly in situ, and metastatic cells became detectable first in the lymph nodes (LNs) and bone marrow, and later in the liver and lungs. We studied MOPC315 cell migration by tracking metastatic cells labelled with green fluorescent protein (GFP). We measured the levels of their chemokine receptor mRNA (by semiquantitative and real-time quantitative reverse transcriptase-polymerase chain reaction (RT-PCR), because chemokines can regulate organ predilection of metastasis. Freshly sorted metastatic cells and tumour cell lines derived from the liver of BALB/c mice overexpressed functional CCR6 and CCR7 molecules compared with primary tumour. Preincubation with the CCR6 ligand (CCL20) induced liver-sorted tumour cells to preferentially colonize the liver, demonstrating an association between liver metastasis and CCR6 expression in the mouse. Because the liver is a common site for metastasis, second only to draining LNs, we wished to ascertain whether this finding could be generalized, i.e. whether other cancers can use the similar mechanism of metastasis to the liver, and whether it holds true for humans. We found that CCR6 is overexpressed in small liver metastases of colon, thyroid and ovarian carcinomas compared with normal liver. Because human liver constitutively expresses CCL20, it could attract and select CCR6+ cancer cells. We suggest that chemotaxis via CCR6 might be a common mechanism by which malignant cancers metastasize to the liver. As metastasis in patients with cancer poses the biggest peril for survival, inhibition of CCR6 signalling, either during or after medical or surgical treatment, might be useful in preventing liver metastasis.

Topical distribution of Fc gammaRI, Fc gammaRII and Fc gammaRIII in inflamed human gingiva.

The topical distribution of Fc gamma receptor types I, II and III (Fc gammaRI-III) was analyzed by means of immunohistochemistry in human gingival tissue obtained from 12 patients with chronic periodontitis. CD68+ macrophages expressing all three classes of Fc gammaR were found throughout the whole gingival connective tissue (CT), whereas dense infiltrates of polymorphonuclear granulocytes (identified by staining for neutrophil elastase) with strong staining for Fc gammaRIII and Fc gammaRII were found subjacent to the apical part of the pocket epithelium (PE) and in the PE itself. CD19+ B lymphocytes with variable staining intensity for Fc gammaRII were observed in clusters subjacent to the PE and extending into the central part of the CT. Only a few scattered CD3+ T lymphocytes stained for Fc gammaRIII. Some spindle-shaped cells (CD68-, therefore non-macrophages) and apparently non-cellular fibrous tissue elements stained for Fc gammaRI and Fc gammaRII. In the epithelium, Fc gammaRII+ dendritic cells were frequently observed in the entire oral gingival epithelium and in the coronal part of the PE. Occasionally, some keratinocytes which stained for Fc gammaRII and Fc gammaRIII were found. The observations indicate that Fc gammaR of the various classes are amply expressed on numerous cell types in inflamed gingival tissue. The specific distribution pattern detected suggests that Fc gammaRs may play a role in the mediation of chronic inflammation in the periodontal lesion.

The gingival plasma cell infiltrate in HIV-positive patients with periodontitis is disorganized.

Patients infected with the human immunodeficiency virus (HIV) are highly susceptible to chronic marginal periodontitis (CMP) and the lesion is generally characterized by abundant plasma cell infiltration. HIV-induced reduction of CD4+ T cells may indirectly affect local production of immunoglobulins (Ig). Gingival biopsies taken from 10 HIV+ and 12 HIV- control patients with CMP were washed, fixed in ethanol and embedded in paraffin. Sections were examined after immunohistochemical staining with monoclonal antibodies against IgA, IgA1-2, IgG, IgG1-4, IgM and IgE. Ig-containing cells were counted in 3 separate connective tissue zones (subjacent to pocket epithelium, central zone and subjacent to oral epithelium). HIV+ patients showed a remarkably increased density of all Ig-containing cells in the connective tissue zone subjacent to the oral epithelium (p<0.05) and a lower % of IgG2+ cells in the entire gingival section (p<0.05). In HIV+ patients, the density of IgG-containing cells in the gingiva was strongly correlated with the serum IgG concentration. The altered topical distribution might imply impaired restriction of the inflammatory lesion, additional antigenic challenges by unusual microorganisms in the oral cavity, or be secondary to HIV-induced dysregulation of the B-cell system.

[Cell surface carbohydrates are involved in various biological processes]. / Karbohydrater på celleoverflater er involvert i en rekke biologiske prosesser.

All human cells show carbohydrate structures on the surface. New knowledge about the genetic mechanisms for the synthesis of these carbohydrates and the generation of monoclonal antibodies with high specificity shows that carbohydrates are involved in various cell-cell and cell-matrix interactions. For instance, cell surface carbohydrates seem to be important in connection with fertilization, embryonic development, cell differentiation, cancer, adhesion of microorganisms and immunological processes. This new knowledge will increase our understanding of various biological phenomena, and will thus be of value for diagnosis and treatment of various diseases.

[Oral cancer. Prognostic aspects]. / Munnhulekreft. Prognostiske aspekter.

The present knowledge regarding growth and progression of intraoral squamous cell carcinoma is still fragmentary. The 5-year survival for these patients is poor. In order to improve the prognosis in this highly lethal cancer, it is important to gain more knowledge about its biological behaviour. In the present paper we suggest that certain cells at the invasive margins of the tumors are most important for prognostic evaluation of the cancer. We have studied the expression of a group of cell membrane bound carbohydrates (blood group antigens) on these deep, invasive cells and found an association between loss of expression of one of these structures and invasion and spread of the cancer cells. Furthermore, we have found a hitherto not reported prognostic value of Rhesus blood groups. We suggest that chromosome instability reported to occur on chromosome 1 in some oral squamous cell carcinomas in some way involve the Rhesus gene that is located in the same area of chromosome 1.