Bcl-2 may play a role in the progression of endometrial hyperplasia and early carcinogenesis, but not linked to further tumorigenesis☆

Bcl-2 expression in reactive oral lesions with atypical epithelium and in oral epithelial dysplasia associated with carcinogen exposure

Background:

Reactive lesions of the oral cavity are nonneoplastic proliferations with very similar appearance to benign neoplastic lesions and are associated with chronic local irritation or trauma. Although these lesions are uncommonly associated with carcinogen exposure, at times, they present histopathologically with dysplastic epithelium, thus making it difficult to differentiate it from true potentially malignant disorders. Hence, the present study was conducted to evaluate the expression of Bcl-2 protein, an antiapoptotic marker, in reactive lesions with and without atypical epithelium and in true epithelial dysplasia, which clinically presents as premalignant disorders.

Materials and Methods:

The samples included 15 cases each of normal oral mucosa (NOM), reactive lesions with and without dysplasia and oral epithelial dysplasia (OED) associated with carcinogen exposure. All the samples were subjected to immunohistochemical staining using Bcl-2 antibody. The total number of cells in the basal and parabasal layers in each field and total number of cells expressing Bcl-2 among them and the staining intensity were assessed.

Statistical Analysis:

Kruskal–Wallis ANOVA test was used to compare the number of positive cells among the four groups. The comparison of average percentage of positive cells between the study groups was done using Mann–Whitney U-test.

Results:

The immunohistochemical staining for Bcl-2 protein was identified in few cells in the basal layers of NOM, reactive lesions without atypical epithelium and in the basal and parabasal layers in reactive lesions with atypical epithelium and OED, as a granular cytoplasmic staining and as an accentuation around the nuclear membrane. There was a gradual increase in the expression and intensity of staining from Group I to IV.

Interpretation and Conclusion:

The altered or increased expression of Bcl-2 oncoprotein in reactive lesions with atypical epithelium and in OED with carcinogen exposure may lead to prolonged cell survival and can be considered as an early molecular event in carcinogenesis, helping us in understanding the nature of dysplasia in reactive lesions, which was not considered during the histopathology reporting.

Craniotomy for a Large and Aggressive De Novo Cavernous Malformation Resection in the Basal Ganglia Region

BACKGROUND

Cerebral cavernous malformations (CCMs) are present in up to 0.5% of the general population. Although CCMs have been considered congenital lesions, numerous reports have observed de novo formations in patients with the familial form of CCM and in patients after cranial radiotherapy. Outside of these circumstances, there is scant evidence as to the potential etiologies of CCM.

CASE DESCRIPTION

We present a 48-year-old woman with a medical history of endometrial hyperplasia concomitant endometrial polyps demonstrating a large de novo CCM, which grew to a large size in a period of 20 months. A previous magnetic resonance imaging scan showed no abnormalities. This CCM exhibited aggressive biological behavior characterized by recurrent overt bleeding and seizure. Histopathologic analysis confirmed the diagnosis of CCM. Here, we discuss the growth mechanisms of these lesions.

CONCLUSIONS

Given the patient's medical history and imaging findings, we propose that de novo CCMs can arise directly from angiogenic proliferation, secondary to BCL-2 overexpression from underlying causes. We hypothesize that inappropriate secretion of estrogen could have set off a genetic cascade with attendant endothelial proliferation. Thus, female hormones may play an important role in influencing the biological behavior of CCMs. The relationship between estrogen and CCM needs further investigation.

Imiquimod Induces Apoptosis in Human Endometrial Cancer Cells In vitro and Prevents Tumor Progression In vivo

PURPOSE

The increasing incidence of endometrial cancer (EC), in younger age at diagnosis, calls for new tissue-sparing treatment options. This work aims to evaluate the potential of imiquimod (IQ) in the treatment of low-grade EC.

METHODS

Effects of IQ on the viabilities of Ishikawa and HEC-1A cells were evaluated using MTT assay. The ability of IQ to induce apoptosis was evaluated by testing changes in caspase 3/7 levels and expression of cleaved caspase-3, using luminescence assay and western blot. Apoptosis was confirmed by flow cytometry and the expression of cleaved PARP. Western blot was used to evaluate the effect of IQ on expression levels of Bcl-2, Bcl-xL, and BAX. Finally, the in vivo efficacy of IQ was tested in an EC mouse model.

RESULTS

There was a decrease in EC cell viability following IQ treatment as well as increased caspase 3/7 activities, cleaved caspase-3 expression, and Annexin-V/ 7AAD positive cell population. Western blot results showed the ability of IQ in cleaving PARP, decreasing Bcl-2 and Bcl-xL expressions, but not affecting BAX expression. In vivo study demonstrated IQ's ability to inhibit EC tumor growth and progression without significant toxicity.

CONCLUSIONS

IQ induces apoptosis in low-grade EC cells in vitro, probably through its direct effect on Bcl-2 family protein expression. In, vivo, IQ attenuates EC tumor growth and progression, without an obvious toxicity. Our study provides the first building block for the potential role of IQ in the non-surgical management of low-grades EC and encouraging further investigations.