TWIST and p-Akt immunoexpression in normal oral epithelium, oral dysplasia and in oral squamous cell carcinoma

Objectives: The aim of this study was to evaluate the immunoexpression of TWIST and p-Akt proteins in oral leukoplakia (OL) and oral squamous cell carcinoma (OSCC), correlating their expressions with the histological features of the lesions. Study design: Immunohistochemical studies were carried out on 10 normal oral epithelium, 30 OL and 20 OSCC formalin-fixed, paraffin-embedded tissue samples. Immunoperoxidase reactions for TWIST and p-Akt proteins were applied on the specimens and the positivity of the reactions was calculated for 1000 epithelial cells. Results: Kruskal-Wallis and Dunn's post tests revealed a significant difference in TWIST and p-Akt immunoexpression among normal oral mucosa, OL and OSCC. In addition, a significant positive correlation was found between TWIST and p-Akt expressions according to the Pearson's correlation test. Conclusions: The results obtained in the current study suggest that TWIST and p-Akt may participate of the multi-step process of oral carcinogenesis since its early stages.

Immunohistochemistry Analysis of Proteins Related with Apoptosis as Prognostic Factor in Epidermoid Carcinoma of Penis

The aim was to analyze the protein expression of apoptotic genes caspase-3, caspase-8 and bcl-2 with the immunohistochemistry technique, correlating with tumor grade (I, II and III) and with the patient survival in order to understand the basic mechanism of tumoral transformation. The immunohistochemistry reactions on 50 samples of squamous cell carcinoma were carried out with the avidin-biotin immunoperoxidase method and antigen recovery. The analyses were made using the graduation method "in crosses" (0 to 4 crosses - no stain to more than 75% of positives cells) and in categories (low, intermediate, high) of the cytoplasm immunoreactivity of the epidermoid penile carcinoma cells. It was observed a statistically significant difference when the expression of caspase-3 were compared with the grades land II of the tumor (p=0.0010) and when comparing the patient survival with the grades I and II of the tumor (p=0.0212). The protein bcl-2 was more expressed than caspase-3 and caspase-8 proteins, suggesting that the apoptotic rate in this carcinoma is low. The higher expression of the anti-apoptotic protein bcl-2 suggests a higher preservation of the tumoral cells.

Hormone-regulated expression and distribution of versican in mouse uterine tissues

Abstract Background Remodeling of the extracellular matrix is one of the most striking features observed in the uterus during the estrous cycle and after hormone replacement. Versican (VER) is a hyaluronan-binding proteoglycan that undergoes RNA alternative splicing, generating four distinct isoforms. This study analyzed the synthesis and distribution of VER in mouse uterine tissues during the estrous cycle, in ovariectomized (OVX) animals and after 17beta-estradiol (E2) and medroxyprogesterone (MPA) treatments, either alone or in combination. Methods Uteri from mice in all phases of the estrous cycle, and animals subjected to ovariectomy and hormone replacement were collected for immunoperoxidase staining for versican, as well as PCR and quantitative Real Time PCR. Results In diestrus and proestrus, VER was exclusively expressed in the endometrial stroma. In estrus and metaestrus, VER was present in both endometrial stroma and myometrium. In OVX mice, VER immunoreaction was abolished in all uterine tissues. VER expression was restored by E2, MPA and E2+MPA treatments. Real Time PCR analysis showed that VER expression increases considerably in the MPA-treated group. Analysis of mRNA identified isoforms V0, V1 and V3 in the mouse uterus. Conclusion These results show that the expression of versican in uterine tissues is modulated by ovarian steroid hormones, in a tissue-specific manner. VER is induced in the myometrium exclusively by E2, whereas MPA induces VER deposition only in the endometrial stroma.

Differential cellular FGF-2 upregulation in the rat facial nucleus following axotomy, functional electrical stimulation and corticosterone: a possible therapeutic target to Bell's palsy

Abstract Background The etiology of Bell's palsy can vary but anterograde axonal degeneration may delay spontaneous functional recovery leading the necessity of therapeutic interventions. Corticotherapy and/or complementary rehabilitation interventions have been employed. Thus the natural history of the disease reports to a neurotrophic resistance of adult facial motoneurons leading a favorable evolution however the related molecular mechanisms that might be therapeutically addressed in the resistant cases are not known. Fibroblast growth factor-2 (FGF-2) pathway signaling is a potential candidate for therapeutic development because its role on wound repair and autocrine/paracrine trophic mechanisms in the lesioned nervous system. Methods Adult rats received unilateral facial nerve crush, transection with amputation of nerve branches, or sham operation. Other group of unlesioned rats received a daily functional electrical stimulation in the levator labii superioris muscle (1 mA, 30 Hz, square wave) or systemic corticosterone (10 mgkg-1). Animals were sacrificed seven days later. Results Crush and transection lesions promoted no changes in the number of neurons but increased the neurofilament in the neuronal neuropil of axotomized facial nuclei. Axotomy also elevated the number of GFAP astrocytes (143% after crush; 277% after transection) and nuclear FGF-2 (57% after transection) in astrocytes (confirmed by two-color immunoperoxidase) in the ipsilateral facial nucleus. Image analysis reveled that a seven days functional electrical stimulation or corticosterone led to elevations of FGF-2 in the cytoplasm of neurons and in the nucleus of reactive astrocytes, respectively, without astrocytic reaction. Conclusion FGF-2 may exert paracrine/autocrine trophic actions in the facial nucleus and may be relevant as a therapeutic target to Bell's palsy.

Immunohistochemical evaluation of MMP-2, MMP-9 and CD31/microvascular density in squamous cell carcinomas of the floor of the mouth

The aim of this study was to evaluate the immunoexpression of MMP-2, MMP-9 and CD31/microvascular density in squamous cell carcinomas of the floor of the mouth and to correlate the results with demographic, survival, clinical (TNM staging) and histopathological variables (tumor grade, perineural invasion, embolization and bone invasion). Data from medical records and diagnoses of 41 patients were reviewed. Histological sections were subjected to immunostaining using primary antibodies for human MMP-2, MMP-9 and CD31 and streptavidin-biotin-immunoperoxidase system. Histomorphometric analyses quantified positivity for MMPs (20 fields per slide, 100?points grade, ×200) and for CD31 (microvessels <50?µm in the area of the highest vascularization, 5 fields per slide, 100?points grade, ×400). Statistical design was composed by non-parametric Mann-Whitney U test (investigating the association between numerical variables and immunostainings), chi-square frequency test (in contingency tables), Fisher's exact test (when at least one expected frequency was less than 5 in 2×2 tables), Kaplan-Meier method (estimated probabilities of overall survival) and Iogrank test (comparison of survival curves), all with a significance level of 5%. There was a statistically significant correlation between immunostaining for MMP-2 and lymph node metastasis. Factors associated negatively with survival were N stage, histopathological grade, perineural invasion and immunostaining for MMP-9. There was no significant association between immunoexpression of CD31 and the other variables. The intensity of immunostaining for MMP-2 can be indicative of metastasis in lymph nodes and for MMP-9 of a lower probability of survival

STAT3 and SOCS3 expression patterns during murine placenta development

Signal transducers and activators of transcription 3 (STAT3) has been identified as an important signal transducer in the invasive phenotype of the trophoblasts cells in in vitro studies. However, the in situ distribution and patterns of expression of this molecule in trophoblast cells during the development of the placenta are still under-elucidated. Mice uteri of gestational ages between 7 and 14 days of pregnancy (dop) were fixed in methacarn and processed with immunoperoxidase techniques for detection of STAT3 and its phosphorylation at serine (p-ser727) residues, as well as the suppressor of cytokine signaling 3 (SOCS3) expression. STAT3 was observed at 7 through 9 dop in both the antimesometrial and mesometrial deciduas, while continued immunoreactivity between 10 and 13 dop was seen only in the mesometrial decidua. In the placenta, STAT3 was detected in the cytotrophoblast cells of labyrinth and giant trophoblast cells between 10 and 14 dop. Immunoreactivity for STAT3 was also seen in trophoblast cells surrounding the maternal blood vessels. On days 10 and 11 of pregnancy, p-ser727 was detectable in the mesometrial decidua and in giant trophoblasts, while during 12-14 dop in the spongiotrophoblast region. In addition, SOCS3 was immunodetected in maternal and placental tissues, principally in the giant trophoblast cells during the whole period of the study. The present in situ study shows the distribution of STAT3, its serine activation and SOCS3 in different maternal and fetal compartments during murine placental development, thus further supporting the idea that they play a role during physiological placentation in mice.