Bcl-2 Protein Expression as Potential
Biomarker of Tumor Progression in Carcinoma
Oral epidermoid
Name: ANNA CLARA GREGORIO CÓ
Publication date: 08/03/2019
Advisor:
Name |
Role |
|---|---|
| SANDRA LÚCIA VENTORIN VON ZEIDLER | Advisor * |
Examining board:
| Name |
Role |
|---|---|
| BRENO VALENTIM NOGUEIRA | Internal Examiner * |
| FAUSTO EDMUNDO LIMA PEREIRA | External Examiner * |
| SANDRA LÚCIA VENTORIN VON ZEIDLER | Advisor * |
Summary: Oral squamous cell carcinoma (OSCC) is the most common histological type of
cancer of the oral cavity and presents a high mortality rate, about 50% of
individuals diagnosed with OSCC evolve to death within a period of up to 5 years.
Currently, there are no biomarkers able to predict prognosis and tumor
progression features, in this way, the study of proteins responsible for apoptotic
control and therefore involved in carcinogenesis has been in evidence. Thus, this
study aims to evaluate the expression of Bcl-2 protein (B-cell lymphoma protein
2) as a prognostic biomarker and tumor progression in OSCC. We used clinical
and follow-up data from 109 individuals with a conclusive diagnosis of OSCC.
Histopathological analysis of gradation, patter of invasion, tumor lymphocytic
infiltrate, perineural, vascular and lymphatic tumor invasion were evaluated on
stained slides in Hematoxylin and Eosin. Fragments of tumor tissue, dysplasia
and adjacent epithelium to the tumor were arranged in tissue microarrays and
submitted to immunohistochemistry using anti-Bcl-2 antibody, clone 124. High
Bcl-2 expression was observed in the tumor tissue, in relation to the adjacent
epithelium to the tumor and dysplasia (p = 0.033), as well as on the tumor
invasion front associated with the high degree of tumor lymphocytic infiltrate (p =
0.001). No difference was observed in Bcl-2 expression in tumor tissue when
compared to clinical-pathological variables: tumor size, lymph node involvement,
staging, age, gender, alcohol consumption and smoking. Additionally, Bcl-2
expression was not associated with prognosis in global and disease-free survival
analyzes. We conclude that Bcl-2 protein may play an important role in indicating
the malignant transformation potential of the oral epithelium in the tumor
progression model used and may be a potential biomarker for the evolution of
high-grade dysplasia for the CEO. However, in this study, Bcl-2 expression did
not prove to be a good prognostic biomarker.
