ABSTRACT: Cell cycle protein expression plays an important role in the pathophysiology of cervical cancer. However, few studies have attempted to correlate the use of these biomarkers with the clinical progression of the tumor.
1) To analyze the expression of Ki-67, p53 and p16(INK4a) in cervical cancer, 2) to correlate the relative expression of these proteins as well as clinical parameters with the stage of disease, and 3) to determine the HPV DNA prevalence and subtype distribution.
Tissue Micro-Arrays (TMA) from patients with invasive cervical cancer (ICC) and controls were analyzed. HPV DNA detection was done by PCR and in situ hybridization. Ki-67, p53 and p16(INK4a) were analyzed by immunohistochemistry; clinical data was derived from the chart review.
Advanced tumor stage (III and IV) was strongly associated (p<0.005) with advanced age (>55 years old), with more than four pregnancies and with the lack of formal education. HPV DNA was found in 94.3% of cases with the most prevalent types being HPV16 (67.5%), followed by HPV33 (12.0%) and HPV35 (3.6%). High expression of Ki-67 and p16 was more common in the advanced FIGO stages (p = 0.023). Women with HPV16 tended to be younger (50.9 years; SE 1.9) compared to women with other types (59.9 years; SE 2.8).
We found that Ki-67 and p16 expression were independently associated with the tumor stage. We also noted that about 1/3 of the cervical cancers in this Brazilian cohort were not associated with HPV types directly targeted by the current HPV vaccines.
PLoS ONE 01/2013; 8(3):e57810. · 4.09 Impact Factor
ABSTRACT: Although several studies have evaluated the role of p16(INK4a) as a diagnostic marker of cervical intraepithelial neoplasia (CIN) and its association with disease progression, studies regarding the role of p16(INK4a) in human immunodeficiency virus (HIV)-infected patients remain scarce. The present study was designed to determine the potential utility of p16(INK4a) as a diagnostic marker for CIN and invasive cervical cancer in HIV-positive and negative cervical specimens. An immunohistochemical analysis of p16(INK4a) was performed in 326 cervical tissue microarray specimens. Performance indicators were calculated and compared using receiving operating characteristics curve (ROC)/area under the curve. In HIV-1-negative women, the percentage of cells that was positive for p16(INK4a) expression was significantly correlated with the severity of CIN (p < 0.0001). A ROC curve with a cut-off value of 55.28% resulted in a sensitivity of 89%, a specificity of 81%, a positive predictive value of 91% and a negative predictive value of 78%. HIV-seropositive women exhibited decreased expression of p16(INK4a) in CIN2-3 specimens compared with HIV-negative specimens (p = 0.031). The ROC data underscore the potential utility of p16(INK4a) under defined conditions as a diagnostic marker for CIN 2-3 staging and invasive cervical cancer. HIV-1 infection, however, is associated with relatively reduced p16(INK4a) expression in CIN 2-3.
Memórias do Instituto Oswaldo Cruz 08/2012; 107(5):571-7. · 2.15 Impact Factor
PLoS ONE 01/2012; 7(4). · 4.09 Impact Factor
ABSTRACT: Minichromosome maintenance proteins (MCM) are highly expressed in actively replicating cells. The need for biological markers for cervical carcinoma and its precursor lesions is emerging. Our main aim was to determine the immunohistochemical expression of MCM-2 in HIV-positive and -negative dysplastic cervical specimens.
Immunohistochemical analysis of MCM-2 was performed in a total of 352 cervical TMA specimens of normal control, low-grade CIN, high-grade CIN and invasive tumor. 38 specimens were from HIV-positive women. A receiver operating characteristic (ROC) curve was constructed to determine the best cutoff to diagnose high-grade CIN and invasive cervical cancer.
In the progression from normal epithelium to high-grade CIN and invasive tumor we found significant differences in the MCM-2 expression (p<0.05). Based on the ROC curve of 80% with an area under the curve (AUC) of 0.78, expression of MCM-2 to diagnose high-grade CIN and invasive tumor resulted in sensitivity of 81%, specificity of 66%, a positive predictive value (PPV) of 86% and a negative predictive value (NPV) of 57%. HIV-positive cervices revealed a decreasing expression of MCM-2 in both LGCIN and HGCIN compared with HIV-negative specimens (p<0.0001).
The present study suggests that immunohistochemical MCM-2 may not be a promising biomarker for diagnosing high-grade CIN and invasive cancer.
PLoS ONE 01/2012; 7(4):e32936. · 4.09 Impact Factor