Bmi-1 expression predicts prognosis in squamous cell carcinoma of the tongue

Abstract

Background: The prognosis of squamous cell carcinoma of the oral tongue is poor and it would be beneficial to find prognostic markers to better adjust treatment. Bmi-1 controls cell cycle and self-renewal of tissue stem cells, transcription factor c-myc affects cell proliferation and apoptosis, and Snail regulates epithelial–mesenchymal transition. The expression of these markers has been connected to prognosis in many cancer types. Methods: Bmi-1, c-myc, and Snail expressions were studied in our material consisting of 73 primarily T1N0M0 oral tongue carcinoma patients. We compared the immunoexpressions of Bmi1, c-myc, and Snail with clinical parameters including the degree of histological differentiation, tumour size, TNM classification, depth of invasion, and resection margins. In addition, survival analyses were performed, comparing disease-free survival time with the registered protein expression of the markers mentioned above. Results: A significant correlation between Bmi-1 protein expression and recurrence (log-rank test, P =0.005) was detected. Snail and c-myc expression did not correlate with prognosis. Snail expression correlated with histopathological grade (Fisher's exact test, P =0.007) and with the invasion depth of tumours ( χ 2 -test, P =0.037). Conclusion: Negative Bmi-1 immunoexpression might serve as a marker of poor prognosis in oral tongue carcinoma patients.

Quantitative determination of c-myc facilitates the assessment of prognosis of OSCC patients

“…On the other hand, c-myc was correlated with tumor stage and lymphatic permeation, while in our study the expression was practically the same. Rodrigo et al (35) found no relationship between c-myc overexpression and tumor prognosis, similar to Hayry et al (33). Baral et al (27) found that tumors with positive p53 and c-myc were in the advanced stages of the disease (poorly differentiated, stage III), while OSCCs in early stages did not show positive immonoreactivity for p53 and c-myc.…”

“…Several studies have analyzed c-myc expression in this type of tumor showing different results, with an average positivity of 41.28% (2.4-75%) between the different studies (6,(26)(27)(28)(29)(30)(31)(32)(33)(34). The results are extremely contradictory, as well as the variation in the quantification methods.…”

Association of BMI-1 and p16 as prognostic factors for head and neck carcinomas

“…Slides were counterstained with Meyer's hematoxylin and mounted in mounting medium (Aquamount, BDH, Poole, UK). The BMI-1 antibody has previously been used in other published studies from our department [14] and p16 is in routine diagnostic use at the Department of Pathology.…”

BMI-1, a promising therapeutic target for human cancer

“…Overexpression of BMI-1 has been previously reported in gastric, ovarian, breast, head and neck, pancreatic and lung cancer, as well as in primary hepatocellular carcinoma (HCC) and endometrial carcinoma (8)(9)(10)(11)(12)(13)(14)(15)(16). In addition, BMI-1 overexpression has been identified in patients suffering from myelodysplastic syndrome, chronic myeloid leukemia, acute myeloid leukemia and lymphoma (17)(18)(19)(20).…”

“…Epithelial-mesenchymal transition (EMT) is the key process driving cancer metastasis and BMI-1 has been demonstrated to induce EMT in endometrial carcinoma cells (28). Furthermore, in vivo studies revealed that BMI-1 expression was upregulated in cancer tissues compared with matched healthy tissues and was associated with distant metastases of gastric cancer (8,29), HCC (15), lung cancer (14,30,31), endometrial carcinomas (16,28,32), and head and neck cancer (11,12,33). Several previous studies have also suggested that BMI-1 contributed to mammary carcinogenesis, axillary lymph node metastases, highly aggressive behavior and late-stage relapse in breast cancer (6,10,(34)(35)(36).…”