Evaluation of argyrophilic nucleolar organizer regions in oral tumor progression

Computer-Assisted Morphometric Comparative Analysis of Argyrophilic Nucleolar Organizer Regions (AgNORs) in Leukoplakia With Dysplasia and Oral Squamous Cell Carcinoma

Background Oral squamous cell carcinoma (OSCC) and oral leukoplakia (OL) with dysplasia are closely linked conditions in the oral cavity, with the latter often indicating precancerous changes, underscoring the urgency of early detection and intervention. Histopathological confirmation is crucial for accurate diagnosis. The nucleolar organizer region (NOR), specifically analyzed through silver-staining (argyrophilic NORs), provides insights into nuclear changes associated with the lesion. Computer-assisted morphometric analysis enhances precision and objectivity in evaluating AgNOR-related parameters. Aim To conduct a computer-assisted morphometric comparison of AgNORs using various NOR-related parameters in cases of OSCC and leukoplakia with dysplasia and to evaluate their diagnostic significance. Materials and methods A computer-assisted morphometric analysis was conducted using various NOR-related parameters, such as nuclear profile area, single AgNOR profile area per nucleus, total AgNOR profile area per nucleus, and number of AgNOR profiles per nucleus on a total sample of 90 specimens, which includes leukoplakia with dysplasia (30), OSCC (30), and a control group, including 30 samples of normal oral mucosa. A comparison was conducted on the morphometric values between the groups under investigation. Tukey's multiple comparison tests and ANOVA were used to analyze the data and determine the differences between the groups. Results The present investigation revealed a significant difference in all four AgNOR-related parameters between leukoplakia and OSCC in comparison to the control group (normal oral mucosa). Comparing OL (41.78 ± 0.46) and OSCC (62.78 ± 0.47) to the control group (35.93 ± 0.99), the mean value of nuclear profile area (A Nuc) was significantly greater. In comparison to the control group (3.40 ± 0.09), the mean value of a single AgNOR profile area per nucleus (A NOR) was found to be relatively lower in both research groups, OL (2.00 ± 0.02) and OSCC (1.39 ± 0.01). The total AgNOR profile area per nucleus (TA NOR) had a mean value of 10.61 ± 0.69 in OL and 12.05 ± 0.28 in OSCC, respectively, compared to 7.82 ± 0.38 in the control group. The study found that there was more number of profiles of AgNORs per nucleus (n NOR) in the study groups of OL (5.30 ± 0.29) and OSCC (8.69 ± 0.19) than in the control group (2.32 ± 0.11). Conclusion The parameters linked to the NOR are biologically informative and easy to check regularly in a pathology lab. Additionally, AgNORs give us important information that enables us to study the range of nuclear changes in malignant and potentially malignant lesions.

Evaluation of AgNORs in Oral Potentially Malignant Lesions

Oral squamous cell carcinoma (OSCC) is usually preceded by detectable mucosal changes, as leukoplakias and erythroplakia. Histologically, these lesions can range from hyperkeratosis and acanthosis to epithelial dysplasia and even OSCC. The aim of this study was to investigate the proliferative activity, using AgNORs quantification proteins, in low- and high-risk oral epithelial dysplasia, OSCC, and nondysplastic epithelium (inflammatory fibrous hyperplasia). The sample was divided into 4 groups: G1: 10 cases of inflammatory fibrous hyperplasia (IFH), G2: 11 cases of low-risk epithelial dysplasia (LD), G3: 10 cases of high-risk epithelial dysplasia (HD), and G4: 11 cases of OSCC. The quantitative analysis was performed using an image processing software in photomicrographs at 1000x magnification. The one-way ANOVA was used for comparison of the mean AgNORs counts between the study groups. The mean AgNORs count was significantly higher (P ≤ 0.01) in OSCC when compared to IFH and the LD; however, it was not statistically different from HD. The mean number of LD was significantly lower than the HD and OSCC, with no difference related to IFH. AgNORs quantification can be an important and cheap method to help in the determination of the degree of epithelial dysplasia and, consequently, in the analysis of their potential for malignant transformation.

AgNORs count and DNA ploidy in liver biopsies from patients with schistosomal liver cirrhosis and hepatocellular carcinoma

OBJECTIVES

Argyrophilic nucleolar organizer regions (AgNOR) proteins are a set of argyrophilic nucleolar proteins that accumulate in highly proliferating cells, whereas their expression is very low in nonproliferating cells. The present study aimed to investigate the potential of DNA flow cytometry (FCM) and AgNORs count in the assessment of cellular kinetics of liver cirrhosis and hepatocellular carcinoma.

DESIGN AND METHODS

Small-needle liver biopsies (217) were included and were taken from 84 patients with hepatocellular carcinoma (HCC) (one biopsy from tumor lesion and the other from residual nontumor) liver tissues. Only one biopsy was taken from 49 patients with liver cirrhosis. One part of biopsy was subjected to flow cytometry, and the other, to histopathology and AgNORs counting.

RESULTS

An aneuploidy was shown in 44.5% of liver cirrhosis and in 78.6% of tumor sites. Aneuploid HCC cases showed high AgNORs count compared with diploid cases (3.407+/-1.18 vs. 1.74+/-0.9). An extremely significant increase in AgNORs count in tumor lesion (P<0.001) was found compared with residual liver tissues, liver cirrhosis and normal liver (3.89+/-0.827, 1.49+/-0.52, 1.62+/-0.29, and 1.3+/-0.17, respectively). In liver cirrhosis, dysplasia showed a significant relationship with ploidy (P<0.001) and AgNORs count (P<0.05).

CONCLUSION

AgNORs count and DNA ploidy analysis of core biopsy specimens are useful in the assessment of cellular kinetics of liver cirrhosis and hepatocellular carcinoma.

Computer-assisted analysis of cell proliferation markers in oral lesions

Abnormalities in any component of the cell cycle regulatory machine may result in oral cancer, and markers of cell proliferation have been used to determine the prognosis of tumor progression. The aim of this study was to determine whether silver-stained nucleolar organizer region (AgNOR) and Ki-67 measurements could improve the assessment of growth rates in oral lesions. Eighty-three oral biopsies were studied, 20 of which were classified as fibrous inflammatory hyperplasia (FIH), 40 as leukoplakia (LKP) and 23 as oral squamous cell carcinoma (OSCC). Within the LKP group, 22 out of 29 biopsies were diagnosed as non-dysplastic leukoplakia (LK) and 18 as dysplastic leukoplakia (DLK), presenting discrete, moderate and severe dysplasia. Ki-67 immunolabeling of the lesions increased steadily in the following order: FIH, DLK, LK and OSCC, indicating that Ki-67 is a good marker for predicting the proliferative fraction among benign, premalignant and malignant oral lesions. The median values of AgNOR parameters indicate that the morphometric index gives better results regarding the proliferative rate than the numerical one. A series of linear regressions between AgNOR parameters and Ki-67 showed positive associations. We conclude that a combination of Ki-67 and morphometric AgNOR analyses could be used as an aid in the determination of the proliferative status of oral epithelial cells in oral cancer.