Expression of MMP-2 and MMP-9 in odontogenic myxoma in a child: report of a clinical case.

BACKGROUND: Odontogenic myxoma (OM) is a benign, locally invasive, non-metastasizing neoplasm of the jaw bones. Despite the benign nature of these lesions, there is a high rate of recurrence and the current recommended therapy, depending on the size and behaviour of the lesion, can vary from curettage with peripheral ostectomy, segmental resection up to radical resections for more aggressive lesions. OM is a rare tumour which occurs predominantly in the third decade of life and it is rare in children. Matrix metalloproteinases (MMPs) are a family of extracellular endopeptidases responsible for the degradation and remodelling of extracellular matrix, they are known to be involved in the progression and invasiveness of many types of tumour. MMPs have been studied in OM because of their well-known role in extracellular matrix degradation, tumour invasion and recurrence. CLINICAL CASE REPORT: We report a case of OM in a 6-year-old boy. A conservative excision was accomplished. The mass was excised without affecting the mandibular bone and the inferior alveolar nerve. Curettage and removal of the first right inferior molar were performed. After 6-month follow-up, no evidence of recurrence was found. EXPERIMENTAL DATA: We investigated the expression of MMP-2 and MMP-9 in this case of OM in a child. RT-PCR showed the expression of both MMP-2 and MMP-9 mRNAs. Immunohistochemistry showed a weak MMP-2 protein expression while MMP-9 protein was not detected. CONCLUSION: In this case of OM in a child, we report lack of recurrence after excision associated with low MMP-2 protein expression and absence of MMP-9. We believe it is worthy to deeply investigate the relationship between MMPs expression and OM behaviour with the aim to use MMPs as prognostic and/or therapeutic markers in OM.

MMP-2, MMP-9, and iNOS expression in human dental pulp subjected to orthodontic traction.

OBJECTIVE: To test the hypothesis that some metalloproteinases (MMP-2, MMP-9) and inducible nitric oxide synthetase (iNOS) enzymes in dental pulp samples do not vary when subjected to orthodontic treatment. MATERIALS AND METHODS: Human dental pulps were taken from male and female patients (N=10; age 10-14 years). A straight wire technique was used with nickel-titanium or steel archwires. The increase of pressure applied on teeth was gradual. Five patients were subjected to premolar extractions after 14 months of treatment and one after 24 months. Samples were Bouin-fixed, paraffin-embedded, and afterwards processed for immunohistochemistry using anti-MMP-2, anti-MMP-9, and anti-iNOS antibodies. RESULTS: A reduction of MMP-2, MMP-9, and iNOS expression occurred in treated samples. This became more evident with increased treatment time. CONCLUSION: The hypothesis is rejected. The reduction of expression of those proteins revealed a time-dependent relationship.

Somatostatin analogues according to Ki67 index in neuroendocrine tumours: an observational retrospective-prospective analysis from real life.

Somatostatin analogues (SSAs) have shown limited and variable antiproliferative effects in neuroendocrine tumours (NETs). Whether tumour control by SSAs depends on grading based on the 2010 WHO NET classification is still unclear. The aim of this study is to evaluate the efficacy of long-acting SSAs in NETs according to Ki67 index. An observational Italian multicentre study was designed to collect data in patients with gastro-entero-pancreatic or thoracic NETs under SSA treatment. Both retrospective and prospective data were included and they were analysed in line with Ki67 index, immunohistochemically evaluated in tumour samples and graded according to WHO classification (G1 = Ki67 index 0-2%, G2 = Ki67 index 3-20%, G3 = Ki67 index > 20%). Among 601 patients with NET, 140 with a histologically confirmed gastro-entero-pancreatic or thoracic NET or NET with unknown primary were treated with lanreotide autogel or octreotide LAR. An objective tumour response was observed in 11%, stability in 58% and progression in 31%. Objective response and tumour stability were not significantly different between G1 and G2 NETs. Progression free survival was longer but not significantly different in G1 than G2 NETs (median: 89 vs 43 months, p = 0.15). The median PFS was significantly longer in NETs showing Ki67 < 5% than in those showing Ki67 ≥ 5% (89 vs 35 months, p = 0.005). SSA therapy shows significant antiproliferative effects in well differentiated low/intermediate-proliferating NETs, not only G1 but also in G2 type. A Ki67 index of 5% seems to work better than 3% to select the best candidates for SSA therapy.

Systemic treatment of gastrointestinal cancer in elderly patients.

PURPOSE: Gastrointestinal cancer (GI) incidence increases with each decade of life and is the leading cause of death in patients aged >70 years. Nevertheless, elderly patients are often excluded or underrepresented in clinical trials. We performed a review of current recommendations in the management of GI elderly cancer patients. METHODS: A comprehensive literature review was performed analyzing data about several meta-analysis and studies regarding chemotherapeutic regimens in elderly patients with colorectal and gastroesophageal cancers. RESULTS: Most of the studies demonstrated that the elderly experience the same advantages and toxicities from chemotherapy as younger individuals despite the fact that the data reviewed in this article provide evidence that elderly with GI cancers are underrepresented in clinical trials and few trials are conducted addressing the different risks and aims in older population. Each individual should be assessed for an appropriate regimen of treatment in the adjuvant or metastatic gastrointestinal cancer setting, and the decision of how to treat elderly must incorporate goals and preferences of the patient after a careful discussion of risks and benefits. CONCLUSION: Chronological age alone is not a sufficient factor to withhold curative/palliative treatment from an elderly GI cancer patient, and cofactors regarding their functional, social, and mental status have to be considered. For this purpose, several tools exist that may be utilized, such as geriatric assessment scores, comorbidity indices, frailty indices, scores for predicting toxicity from chemotherapy, and prognostic indices for survival.

Human umbilical cord expresses several vasoactive peptides involved in the local regulation of vascular tone: protein and gene expression of Orphanin, Oxytocin, ANP, eNOS and iNOS.

Full-term human umbilical cord contains three blood vessels: two arteries coiled around a vein and surrounded by Wharton's jelly, a mucous tissue with few mesenchymal stromal cells and abundant extracellular matrix. Umbilical vessels lack innervations, thus endothelial cells must play a role in the control of blood flow. The aim of this study was to investigate in human umbilical cord the expression of five peptides that could be involved in the regulation of vascular tone: Orphanin FQ, Oxytocin, Atrial Natriuretic Peptide (ANP), endothelial Nitric Oxide Synthase (eNOS) and inducible Nitric Oxide Synthase (iNOS). The expression of these molecules in full-term human umbilical cord was investigated through immunohistochemistry and RT-PCR. Immunoreactivity for Orphanin FQ was detected in Wharton's jelly, vessel musculature and endothelium; Oxytocin, ANP and eNOS were expressed by the umbilical epithelium, Wharton's jelly and endothelium, whereas iNOS only by endothelial cells. RT-PCR analysis showed transcriptional expression of Oxytocin, ANP and eNOS mRNAs. The presence of Orphanin, Oxytocin, ANP, eNOS and iNOS proteins was identified in the human umbilical cord. mRNA expression for Oxytocin, ANP and eNOS suggest that these molecules are synthesized by umbilical cord cells themselves. The expression of these vasoactive molecules could be part of a general mechanism locally regulating vascular tone.

Immunohistochemical and transcriptional expression of matrix metalloproteinases in full-term human umbilical cord and human umbilical vein endothelial cells.

Matrix metalloproteinases (MMPs) are extracellular zinc-dependent endopeptidases involved in the degradation and remodelling of extracellular matrix in physiological and pathological processes. MMPs also have a role on cell proliferation, migration, differentiation, angiogenesis and apoptosis. Umbilical cord is a special organ subjected to many changes during pre-natal life and whose cells can maintain a certain degree of plasticity also in post-natal period; for example recently they have been used as a source of stem cells. In this work we investigated the expression of MMPs in human umbilical cord and human umbilical vein endothelial cells (HUVEC) though immunohistochemistry, RT-PCR and gelatin zymography. MMP-2 protein is expressed in the amniotic epithelium of human umbilical cord and in few sub-epithelial fibroblasts, while MMP-3 and MMP-10 only in the umbilical epithelium. MMP-8, MMP-9 and MMP-13 immunoreactivity is localised in the epithelium and in Wharton's jelly mesenchymal cells. Immunocytochemistry also revealed protein expression for MMP-2, 3, 8, 9 and 10 in cultured HUVEC. In agreement with immunohistochemical data, RT-PCR analysis performed on samples of whole umbilical cord confirmed the transcriptional expression for the genes encoding all the six matrix metalloproteinases investigated, while in HUVEC only the expression of MMP-2, 3, 9, 10 and 13 mRNAs was detected. Gelatin zymography showed a clear MMP-2 and MMP-9 enzymatic activity in the conditioned medium of HUVEC at different culture passages, suggesting that HUVEC secrete gelatinases, that afterwards undergo extracellular activation, and this ability is not affected by passage number.

Expression of cyclooxygenase-1 and cyclooxygenase-2 in normal and pathological human oral mucosa.

Cyclooxigenase (COX) is the rate-limiting enzyme for the conversion of arachidonic acid (AA) to prostaglandins (PGs). Two isoforms of COX have been identified: COX-1 is constitutively expressed in many cells and is involved in cell homeostasis, angiogenesis and cell-cell signalling; COX-2 is not expressed in normal condition however it is strongly expressed in inflammation. The oral cavity is constantly exposed to physical and chemical trauma that could lead to mucosal reactions such as hyperplasia, dysplasia and cancer. Early diagnosis is the most important issue to address for a positive outcome of oral cancer; therefore it would be useful to identify molecular markers whose expression is associated with the various stages of oral cancer progression. Since COX enzyme has been involved, with different mechanisms, in the development and progression of malignancies we decided to investigate the expression and localization of COX-1 and COX-2 in normal human oral mucosa and three different pathologies (hyperplasia, dysplasia and carcinoma) by immunohistochemistry and RT-PCR. COX-1 mRNA and protein have been detected already in normal oral mucosa and their expression progressively increases from normal samples towards hyperplasia, dysplasia and finally carcinoma. On the contrary, COX-2 is not expressed in the normal tissue, starts to be expressed in hyperplasia, reaches the maximum activation in dysplasia and then starts to be downregulated in carcinoma.

Endothelial dysfunction in mice with streptozotocin-induced type 1 diabetes is opposed by compensatory overexpression of cyclooxygenase-2 in the vasculature.

Cardiovascular complications of diabetes result from endothelial dysfunction secondary to persistent hyperglycemia. We investigated potential compensatory mechanisms in the vasculature that oppose endothelial dysfunction in diabetes. BALB/c mice were treated with streptozotocin (STZ) to induce type 1 diabetes (T1D). In mesenteric vascular beds (MVBs), isolated ex vivo from mice treated with STZ for 1 wk, dose-dependent vasorelaxation to acetylcholine (ACh) or sodium nitroprusside was comparable with that in age-matched control mice (CTRL). By contrast, MVBs from mice treated with STZ for 8 wk had severely impaired vasodilator responses to ACh consistent with endothelial dysfunction. Pretreatment of MVBs from CTRL mice with nitric oxide synthase inhibitor nearly abolished vasodilation to ACh. In MVB from 1-wk STZ-treated mice, vasodilation to ACh was only partially impaired by L-N(omega)-arginine methyl ester. Thus, vasculature of mice with T1D may have compensatory nitric oxide-independent mechanisms to augment vasodilation to ACh and oppose endothelial dysfunction. Indeed, pretreatment of MVBs isolated from 1-wk STZ-treated mice with NS-398 [selective cyclooxygenase (COX)-2 inhibitor] unmasked endothelial dysfunction not evident in CTRL mice pretreated without or with NS-398. Expression of COX-2 in MVBs, aortic endothelial cells, and aortic vascular smooth muscle cells from STZ-treated mice was significantly increased (vs. CTRL). Moreover, concentrations of the COX-2-dependent vasodilator 6-keto-prostaglandin F-1alpha was elevated in conditioned media from aorta of STZ-treated mice. We conclude that endothelial dysfunction in a mouse model of T1D is opposed by compensatory up-regulation of COX-2 expression and activity in the vasculature that may be relevant to developing novel therapeutic strategies for diabetes and its cardiovascular complications.