E-cadherin and c-Met expression in actinic cheilits and lip squamous cell carcinoma

Objective: The aim of this study was to assess epithelial expression of E-cadherin and c-Met in normal lip, in actinic cheilitis and lip squamous cell carcinoma. Study Design: Biopsies of normal lip vermillion (NL, n=18), actinic cheilitis (AC, n=37), and lip SCC (n=22) were processed for E-cadherin and c-Met immunodetection. Epithelial and tumor cell expression was scored for each sample considering staining intensity and percentage. Results: E-cadherin expression was significantly reduced in AC and lip SCC as compared to normal lip (P<0.05), with a significant reduction in lip SCC as compared to AC (P=0.003). Expression of c-Met was significantly higher in AC and lip SCC as compared to NL (P<0.05), with a significant increase in lip SCC as compared to AC (P<0.0001). Conclusion: The results showed that epithelial E-cadherin expression is reduced and c-Met expression is increased as lip carcinogenesis progresses, suggesting that these proteins may be useful markers of malignant transformation.

Single exposure of human oral mucosa fibroblasts to ultraviolet B radiation reduces proliferation and induces COX-2 expression and activation

The lip vermillion constitutes a transition tissue, between oral mucosa and skin, where oral mucosal cells from epithelial and connective tissue compartments are exposed to ultraviolet (UV) sunlight. Fibroblasts are abundant resident cells of the connective tissue which are key regulators of extracellular matrix composition, as well as, epithelial and endothelial cell function. UVB light, an inherent component of sunlight, causes several alterations in skin fibroblasts, including premature senescence and increased cyclooxygenase (COX)-2 expression. To assess if UVB irradiation had similar effects on fibroblasts derived from human oral mucosa (HOM), primary cultures of HOM fibroblasts were irradiated with a single dose of 30 or 60 mJ/cm²of UVB light or sham-irradiated. Fibroblast proliferation was assessed from 3 to 48 hrs after UVB-irradiation utilizing [³H]-thymidine incorporation and MTT assays. In addition, COX-2 mRNA expression was detected by RT-PCR, and PGE2 production was assessed using enzyme immunoassay from 0.5 to 24 hrs after UVB-irradiation. The results showed a significant decrease in proliferation of UVB-irradiated HOM fibroblasts as compared to controls as measured by both [³H]-thymidine incorporation and MTT assays (p<0.001). HOM fibroblasts had increased COX-2 mRNA expression at 0.5 and 12 hrs after irradiation, and PGE2 production was elevated at 12 and 24 hrs post-irradiation as compared to controls (p<0.05). The results showed an inhibitory effect of a single dose of UVB irradiation on HOM fibroblast proliferation with an increase in COX-2 expression and activation. Therefore, photodamaged fibroblasts may play and important role in the pathogenesis of UV-induced lesions of the lip.

Estudio comparativo: prevalencia patologías bucales en pacientes pediátricos oncológicos 1997-2007 / Comparative study: oral pathologies prevalence in pediatric oncology patients 1997- 2007

Los pacientes pediátricos oncológicos con frecuencia presentan lesiones orales debido a su neoplasia o como efecto colateral del tratamiento. El objetivo de este estudio fue comparar la prevalencia de patologías de la mucosa oral en niños con cáncer que fueron hospitalizados y tratados con quimioterapia en el Hospital Regional de Concepción, en los años 1997 y 2007. Se realizó un estudio descriptivo retrospectivo longitudinal en datas de 148 pacientes (74 cada año) con patologías neoplásicas en tratamiento con quimioterapia (Leucemias, linfomas, tumores del Sistema Nervioso Central y otros), registrando sus datos generales y la patología bucal (mucositis (M), candidiasis (C), lesiones por Virus Herpes tipo 1 (VHS) y síndromes hemorragíparos (H) . Los datos se resumieron en tablas anuales y fueron sometidos a análisis estadísticos. Se encontró una disminución significativa del número de pacientes con patologías bucales en el año 2007 en relación al año 1997 (P<0.05, Tet de Fisher). Además se encontró una tendencia a la baja en los pacientes con candidiasis y con mucositis en el año 2007 en comparación con 1997. Es necesario seguir estudiando medidas para prevenir, diagnosticar y/o tratar tempranamente las patologías orales de los pacientes en tratamiento antineoplásico.

Pediatric oncology patients frequently have oral lesions due to malignancy or as a side effect of treatment. The aim of this study was to compare the prevalence of oral pathologies in oncology patients hospitalized and treated at the Regional Hospital of Concepción, Chile, in the years 1997 and 2007. A retrospective study was carried out in 74 patients each year. Patients suffered from acute lymphoblastic leukemia, acute myeloblastic leukemia, central nervous system tumors, lymphomas and other neoplasms. General data (age, gender, oncologic disease) and presence of oral pathologies (candidiasis, mucositis post-chemotherapy, herpetic lesions and hemorrhage) were obtained from their clinical records. Data was analyzed for statistical differences. A significant reduction in the number of patients with oral pathologies was found in 2007 in comparison to 1997 (P<0.05, Fisher´s test). In addition, candidiasis and oral mucositis showed less prevalence in 2007 as compared to 1997, although no significant differences were found. For the relevance of oral pathologies in the chemotherapy it´s important to continue studies about prevention, early detection and treatment of oral pathologies.

TNFa increases in vitro migration of human HPV18-positive SW756 cervical carcinoma cells

TNFa has been associated with both, tumor survival and apoptosis. This cytokine is also involved in promoting cell migration during wound healing and tumorigenesis. SW756 is a HPV18-positive cervical carcinoma cell line, which has been used to study different mechanisms of cervical cancer progression. An in vitro assay of scratch wound healing onto monolayers of SW756 cells was used to assess the effect of TNFa on cell migration into a wound space. It was found that SW756 cells have the ability to migrate, but not proliferate in response to scratch wounding in a serum-free medium supplemented with TNFa. RT-PCR analysis showed that SW756 cells express TNFa mRNA when incubated in medium with and without serum. Wound closure and migration rate of SW756 cells were significantly increased in the presence of serum-free media supplemented with TNFa (10 ng/mL) as compared to serum-free media, and media supplemented with either anti-TNFa antibody or both TNFa and anti-TNFa antibody (p<0.05). The results showed a stimulatory effect of TNFa on the migration of SW756 cervical carcinoma cells, suggesting a novel and important role for TNFa in cervical cancer progression.

Uterine mast cells: a new hypothesis to understand how we are born

Birth is the result of complex, well-defined, and coordinated events, that are tightly regulated by endocrine, nervous, and immune responses, and take place primarily in the female reproductive tract. Various mechanisms and mediators involved in pregnancy, labor, and delivery, are highly conserved among different mammalian species and mast cells emerge as potential and crucial participants in these processes, as it is discussed in this review.