Argyrophilic nucleolar organizer regions (AgNOR) in gastric cell of obese patients with bariatric surgery

Three hundred and fifty biopsies from patients undergoing upper gastrointestinal endoscopy were studied for histopathological changes, H. pylori infection and argyrophilic nucleolar organizer region (AgNOR) counts. Histopathological examination revealed normal gastric mucosa in 10 (2.85%), gastritis in 254 (72.56%), intestinal metaplasia in 12 (4.0%), dysplasia in 13 (3.7%) and adenocarcinoma in 61 (17.4%). The mean (SD) AgNOR count was 1.66 (0.20) in normal, 2.43 (0.64) in gastritis, 3.09 (0.52) in intestinal metaplasia, 4.17 (0.31) in dysplasia, and 6.57 (0.98) in carcinoma. A statistically significant difference was observed between the AgNOR count of normal gastric mucosa and gastritis (p<0.001), gastritis and dysplasia (p<0.001), and dysplasia and adenocarcinoma (p<0.001). A statistically significant increase in mean AgNOR count was found with increase in H. pylori density in gastric biopsies (p<0.001) with gastritis. No significant difference was observed between mean AgNOR count of intestinal and diffuse type carcinomas. The AgNOR count in gastric biopsies with adenocarcinoma and H. pylori infection was 7.03 (0.85) as compared to 6.89 (0.73) in gastric biopsies with evidence of adenocarcinoma but without H. pylori infection. The difference was not statistically significant. The findings support the role of H. pylori as a promoting agent in gastric carcinogenesis by stimulating gastric epithelial cell proliferation at the stage of chronic inflammation, thereby making the cells more susceptible to endogenous or exogenous carcinogenic agents.

Background and aimsSeveral diagnostic methods are being employed to detect benign and malignant lesions, one of which is silver nitrate staining for organizer regions. The number of nucleolar organizing regions (NORs) can be used to show the degree of cell activity or metabolism in pathologic lesions. This study was designed to evaluate NORs as determi-nants of precancerous and squamous cell carcinoma.Materials and methodsA silver colloid technique was applied on paraffin sections of 40 cases of oral squamous cell carcinoma and 25 cases of precancerous lesions; 15 specimens of normal epithelium were selected for the control group. After staining with silver nitrate, argyrophilic nucleolar organizer regions (AgNORs) were counted in 100 epithelial cells in three groups with the use of an oil immersion and ×1000 objective lens. One-way ANOVA and a post hoc Tukey test were used for statistical analysis.ResultsThe mean numbers and standard deviations of AgNORs were 1.58 ± 0.76 in normal epithelium, 2.1 ± 1.05 in pre-cancerous lesions and 2.43 ±1.33 in squamous cell carcinoma (SCC). There were statistically significant differences in Ag-NORs numbers between the groups (P<0.001) and significant differences in precancerous lesions between dysplastic and non-dysplastic epithelia (P<0.001). The mean AgNORs count per nucleus increased from healthy epithelium to precancer-ous lesion to SCC.Conclusion This study suggests that the silver staining technique for the detection of NORs (AgNOR) can be used to distinguish precancerous lesions and benign and malignant lesions.

Nucleolar organizer regions are loops of DNA containing ribosomal RNA genes and presumably are associated with ribosomal RNA activity, protein synthesis, and cell proliferation. Argyrophilic nucleolar organizer region (AgNOR) count has been suggested as an objective method in differentiating dysplastic lesions from non-dysplastic lesions. This descriptive study was done on archival paraffin blocks (n = 60), consisting of 10 normal human oral epithelium, 22 cases of non-dysplastic leukoplakia (NDLK), and 28 cases of dysplastic leukoplakia (DLK). The AgNORs were counted with the aid of a manual using conventional light microscopy and photographs of the same were taken and analyzed using Image Pro Express 6.0 (Media Cybernetic Inc., USA) for windows. The mean AgNOR count per nucleus was found to be higher in patients with DLK as compared to NDLK and controls using both manual counting and image analysis method and on comparing both the techniques, image analysis provide a more accurate reflection of AgNOR counts than manual counting. To conclude, reliability of computerized image technique of AgNOR count is the most appropriate marker to differentiate between dysplastic and NDLK. Computer-assisted image analysis system was found to be an effective tool in achieving high reproducibility as compare to manual.

Evaluation of the argyrophilic nucleolar organizer region, nuclear DNA content and mean nuclear area in transitional cell carcinoma of bladder using a quantitative image analyzer.

Lichen planus is a mucocutaneous disease, and its potential for malignant transformation is a subject of controversy. We found dysplastic changes in slide review of about 11% of oral lichen planus (OLP) in our previous research. Dysplastic changes can be an initial phase for carcinogenesis. The question is whether it is possible to detect early malignant changes in OLP through the evaluation of proliferation activity. The aim of this study was to compare the cell proliferation activity in dysplastic and nondysplastic oral lichen planus using the quantitative and qualitative analysis of argyrophilic nucleolar organizer region (AgNOR) and to compare candidal infection in these 2 groups. In this cross-sectional, observational, and analytical study, all 14 cases of confirmed dysplastic OLPs and 17 nondysplastic OLPs were stained with an AgNOR technique. Analysis of argyrophilic nucleolar organizer region dots were counted in 100 cells of basal and parabasal layers, and proliferation index (cells with ≥ 5 dots in nucleus) and variations in size of AgNOR dots were also evaluated. Periodic acid-Schiff staining was performed for detection of candidal infection. Mean AgNOR count in dysplastic OLP (2.39 ± 0.2) was more than nondysplastic OLP (2.27 ± 0.59). Candidiasis was found in 14.3% of dysplastic OLP and in 12.5% of nondysplastic OLP. There was no statistically significant difference between the 2 groups in mean AgNOR count (P = 0.62), variation in size of AgNOR dots (P = 1), proliferation index (P = 0.53), and candidiasis (P = 1). The current study showed slight difference in proliferation rate and candidal infection between dysplastic and nondysplastic OLP.

INTRODUCTION: Odontogenic tumors are diverse groups of lesions derived from odontogenic tissues. Clinical behavior of these lesions varies widely, ranging from benign to malignant with differences in recurrence rate and growth pattern. A better understanding of the underlying molecular mechanisms will help to predict the course of odontogenic tumors and lead to the development of new therapeutic applications. Nucleolar organizer regions (NORs) are loops of DNA that codify the ribosomal RNA and are considered important for protein synthesis. The NORs stained histochemicaly by silver are named argyrophilic nucleolar organizer regions (AgNOR). Quantification of AgNOR represents a valuable parameter of cell kinetics and therefore cell proliferation. The number of AgNOR sites in malignant cells is significantly greater than those in their normal or benign counterparts. Proliferating cell nuclear antigen (PCNA) is a useful marker of cellular proliferation and DNA replication. Malignant tissue is characterized by an uncoordinated proliferating cell nuclear antigen (PCNA). OBJECTIVES: To evaluate the cell proliferation rate using the expression of Argyrophilic Organizing Region counts and Proliferating Cell Nuclear Antigen in epithelial odontogenic tumors and to assess the usefulness of AgNOR and PCNA as markers in malignant potential of epithelial odontogenic tumors. MATERIALS AND METHODS: This study was done on 45 surgical specimens of epithelial odontogenic tumors and one control specimen from normal tooth germ.The tissue biopsies were processed and paraffin sections were prepared. Hematoxylin and eosin-stained sections were examined for diagnosis. Other sections were subjected to AgNORhistochemical technique and immunohistochemical staining for PCNA. Immunohistochemical staining was performed using a Labeled Strept-Avidin Biotin complex method (LSAB). RESULTS: The mean AgNOR count of tooth germ was 1.21 and the benign odontogenic tumors was 1.862.The highest AgNOR count was recorded in Ameloblastic carcinoma and lowest was seen in adenomatoid odontogenic tumor. Statistically significant difference in AgNOR counts of ameloblastoma and adenomatoid odontogenic tumor, ameloblastoma and calcifying epithelial odontogenic tumor, benign odontogenic tumors and ameloblastic carcinoma were seen. AgNORs in ameloblastic carcinoma were more in number and more widely distributed.The highest mean value of PCNA-positive cell percentage was demonstrated in ameloblastic carcinoma followed by ameloblastoma. A significant difference was noted when the PCNA value of ameloblastoma was compared with that of ameloblastic carcinoma. CONCLUSIONS: AgNOR technique may be considered a good indicator of cell proliferation in epithelial odontogenic tumors.The PCNA expression, along with the clinical features, can predict the aggressiveness, chances of recurrence and malignant potential of these tumors.

Background: Nucleolar organizer regions(NORs) are chromosomal segments encoding for ribosomal RNA and associated with argyrophilic nonhistone protein. Ribosomal RNA genes ultimately direct ribosome and protein synthesis, and it has been suggested the numbers of NORs detected in the cell may reflect nuclear and cellular activity. This study was performed to evaluate the applicability of AgNORs to the diagnosis of squamous cell carcinoma of the lung. Method: The one step silver methods(AgNORs) was used to stain NORs in the routinely processed, formalin fixed, paraffin embedded sections of 36 cases of squamous cell carcinoma of the lung obtained by surgical resection of primary tumor. In each specimen, 100 tumor cells and 100 normal cells adjacent to the tumor chosen at random were examined under an oil immersion lens at a magnification of . The mean number of AgNORs per nucleus was calculated for each specimen. Results: The mean number of AgNORs per nucleus(mAgNORs) of normal bronchial epithelium and squamous cell carcinoma of the lung was and , respectively. The difference of mAgNOR between normal and tumor tissue was statistically significant(p

Background. Argyrophilic nucleolar organizer region (AgNOR) has been demonstrated in recent studies of human brain tumors, including meningiomas. The authors used this technique in meningiomas to analyze whether the mean numbers of AgNOR per nucleus (AgNOR score) are related to the recurrence rate or the proliferative potential of meningiomas. Methods. AgNOR staining technique was applied to paraffin-embedded sections of 60 meningiomas. Twenty of these specimens also were investigated immunohisto-chemically with monoclonal antibody (MoAb) against DNA polymerase α (Pol.α) and with MoAb Ki-67 to compare the AgNOR score with the proliferative potential. Results. There was a statistically significant difference between the AgNOR score in nonrecurrent meningiomas (2.48 ± 0.73) and recurrent histologically benign meningiomas after gross total resection (3.20 ± 0.96) (P < 0.02). The recurrence rate of tumors after gross total resection with an AgNOR score of 3.0 or more was significantly higher than that with an AgNOR score of less than 3.0. The AgNOR score did not always correlate with Pol.α or Ki-67 score; the AgNOR score of malignant meningioma that had high proliferative score was not always high. Conclusions. This study indicates that AgNOR staining appears to be a simple and useful method for estimating the probability of histologically benign meningioma recurrence even after gross total resection.

The Ki-67 antibody binds to nonresting cells where Ki-67 labeling index (KLI) reflects proliferative activity (PA). The argyrophilic nucleolar organizer regions (AgNOR) counts have been correlated to ploidy and/or PA. Two AgNOR counting methods distinguish ploidy from PA. The first count is the mean AgNOR count (mAg-NOR) which correlates with ploidy. The second is the percentage of nuclei with > or = 5 AgNORs/nucleus (pAgNOR) which reflects PA. To explore this relationship, we separately stained smears of 20 fine-needle aspirates (FNAs) of lymphoproliferative disorders (n = 12) and breast carcinomas (n = 8) for AgNOR and Ki-67. We also double-stained 10 of the smears for both AgNOR and Ki-67. The correlation of pAgNOR counts and KLI was statistically significant (P < 0.0001) whereas it was not between mAgNOR and KLI (P = 0.13). Additionally, using the double stain, the Ki-67 negative cells had an AgNOR granule range of 1-3/nucleus with a mean of 1.33 (+1.86 SD). The Ki-67 positive cells showed an AgNOR granule range of 2-12/nucleus with a mean of 4.15 (+/- 1.02 SD) (P < 0.0002). We thus conclude that pAgNOR is a more reliable indicator of PA than mAgNOR and that four AgNORs/nucleus is an acceptable number differentiating proliferating from resting cells.

B-cell chronic lymphocytic leukemia (B-CLL) is typically a low-grade neoplasm with a diploid DNA index and low proliferative activity. Interleukin-2 receptor (IL-2R/CD25) positivity often indicates increased proliferative activity and activation in both T and B lymphocytes. The argyrophilic nucleolar organizer regions (AgNORs) are loops of DNA identified by a silver staining technique and have been correlated with ploidy and proliferative activity. Two distinct AgNOR counting methods have been previously shown to correlate with DNA ploidy and proliferative activity, respectively: the mean AgNOR count (mAgNOR) correlates more with ploidy, and the percentage of nuclei with > or = 5 AgNORs/nucleus (pAgNOR) reflects proliferative activity. We studied bone marrow specimens from 32 patients with B-CLL using both anti-IL-2R on the marrow aspirates and the AgNOR silver stain on marrow biopsy specimens, applying both AgNOR counts. All tumors were CD5+, CD19+, and CD19/CD20+. Sixteen tumors were IL-2R- (< 20% IL-2+ B cells), and 16 were IL-2R+ (> or = 20% IL-2R+ B-cells). No significant difference in morphology of bone marrow involvement was noted in the two groups. A male predominance was noted in the IL-2R+ group of patients (3:1). There was also a preponderance of lambda light chain expression in the IL-2R+ tumors (11/16) compared with the IL-2R- cases (5/16). Except for two cases, all tumors had mAgNOR counts within the diploid range (< 2.4). The 16 IL-2R- tumors had pAgNOR in the range of 0% to 7% (mean, 2.31 +/- 2.18 standard deviation), whereas the IL-2R+ tumors had pAgNOR ranging from 6% to 15% (mean, 10.20 +/- 2.70 standard deviation; P < .0001). This finding suggests that IL-2R+ B-CLL might represent a subgroup of tumors with higher proliferative activity.

The argyrophilic nucleolar organizer regions (AgNOR) are silver stained granules that are thought to correlate with cell proliferation activity. Two AgNOR counting methods: the mean AgNOR count (mAgNOR, the mean number of AgNOR granules in 100 cells) and the AgNOR proliferative index (pAgNOR, the percentage of cells exhibiting five or more AgNOR granules per nuclei) have been proposed. In this study, the two counting methods were applied to 58 cases of normal uterine corpus and uterine corpus tumors and were compared with the Ki-67 labeling index (Ki-67 LI) using MIB-1 monoclonal antibody and other histopathological criteria. Notable differences in the number of AgNOR and the Ki-67 LI were observed between benign and malignant smooth muscle tissue. Histopathologic features are well correlated to the proliferative activity of tumors. Although the most reliable method of predicting malignant potential cannot be determined, the methods outlined by this study are thought to be highly useful in assessing proliferative activities.

Increased expression of argyrophilic nucleolar organizer regions (AgNORs) has been identified in certain malignant tumors including nasopharyngeal carcinoma (NPC). However, its prognostic significance in NPC is uncertain and remains to be evaluated. To address this we silver-stained 63 paraffin sections of NPC cases, and examined the correlation between AgNOR count and area, calculated by the CAS 200 image analysis system, and tumor behavior, locoregional control, and survival of patients. The mean AgNOR count and area were 1.62 +/- 0.31 and 3.98 +/- 11.4 microm2, respectively. The AgNOR area was positively associated with T stage (r = 0.26, P = 0.04). The Mann-Whitney test confirmed no significant difference in AgNOR area and count between patients with different outcomes. Multivariate analysis using the Cox proportional hazard model showed neither AgNOR count nor area to be significant predictors of actuarial survival or disease-free survival. It is concluded that AgNOR does not have an independent and significant prognostic value in NPC. AgNOR expression may be merely a reflection of malignant phenotype as well as cellular activity but not necessarily the ultimate behavior of the tumor.

Serous effusion smears reported as (suspicious for malignancy) pose problems in clinical management. Silver staining for argyrophilic nucleolar organizer regions (AgNOR) has proved useful in making a cytopathologic differential diagnosis between benign and malignant cells. Nucleolar organizer regions(NORs) are loops of DNA located in acrocentric chromosomes. These NORs are visualized by silver staining technique that recognizes these argyrophilia associated proteins which are increased in malignancy. This study aimed to distinguish reactive mesothelial cells from malignant cells in serous effusions using these NORs. A total of 174 serous effusions received at the Department of Pathology, TUTH, during a period of one year were included in the study. Smears were studied by conventional Papanicolaou and Giemsa stains. AgNOR counts, variation in size and dispersion of AgNOR dots in smears were graded and compared in malignant and non-malignant effusions. Mean AgNOR counts of 10.43+\-0.73 and 10.21+\-0.51 in malignant peritoneal and pleural effusions, respectively, were significantly (p < 0.0001) greater as compared with counts of 2.12 +\- 0.54 and 2.11 +\- 0.54 in non-malignant effusions. The AgNORs were irregular in shape in malignant effusions whereas they were comparatively larger, single dots in benign effusions. AgNOR size and dispersion were of higher grade in significantly greater proportion of malignant as compared with non malignant effusions (p < 0.0001). Of the cytologically suspicious samples, nine were in the malignant range and one was in the benign range. AgNOR study appears to be clinically useful as an additional diagnostic tool for use in serous effusion when the cytologic diagnosis is difficult.

Background: Breast cancer is one of the leading cancers in women both in developed and developing countries. Nucleolar Organizer Regions (NORs) are loops of DNA related to protein synthesis and ribosomal activity. Argyrophilic Nucleolar Organizer Region (AgNOR) counts act as a reliable cell proliferative marker as they aid in identifying cell proliferation activity and aggressiveness of a lesion, and thereby helps in differentiating benign and malignant breast lesions.&#x0D; Aim: To evaluate the role of AgNOR count in differentiating benign and malignant breast lumps.&#x0D; Methods: All breast lump specimens collected for Fine Needle Aspiration Cytology (FNAC) and histopathology, for a period of one year, were included in the study. A total of 69 specimens were included. All FNAC and histopathology slides were stained with AgNOR stain, and the score was recorded.&#x0D; Result: A total of 69 cases were studied, both non-neoplastic and neoplastic breast lesions. All FNAC cases correlated histologically. Out of the 69 cases, 38 were malignant. The mean AgNOR counts in non-neoplastic, benign and malignant breast lesions were found to be 2.19, 2.88 and 5.94 respectively (p&lt;0.05). Other parameters such as proliferative AgNOR index, AgNOR size variation, AgNOR distribution within the nucleus and the Subjective AgNOR Pattern Assessment (SAPA) scores also showed statistically significant difference between benign and malignant lesions.&#x0D; Conclusion: AgNOR scores showed good correlation in differentiating benign and malignant breast lesions, they can be used as a reliable tool to aid in the diagnosis.

Argyrophilic nucleolar organizer regions (AgNOR) of 79 prostatic adenocarcinomas, and an immunohistochemical stain using a monoclonal antibody against proliferating cell nuclear antigen (PCNA) of 54 prostatic adenocarcinomas, obtained by needle biopsy and transurethral resection of the prostate between 1986 and 1989, were investigated. A morphological classification was devised to count silver dots based on the relations between intra- and extra-nucleolar AgNOR (type A, B, C and D). Total AgNOR counts were significantly higher in carcinoma (4.2 +/- 1.57) than in the benign prostatic lesions (1.90 +/- 0.24). Count differences of AgNOR were evident in histological differentiation, nuclear anaplasia, and presence of nucleoli, mitosis, lymphatic invasion and vascular invasion. Higher total AgNOR counts were almost always associated with type B and C AgNOR (intranucleolar AgNOR), but were not associated with type A (nucleolus without small dot) nor type D (extra-nucleolar AgNOR). This study shows the diagnostic value of AgNOR in prostatic cancer, and the importance of morphological classification of AgNOR. The survival of patients with higher AgNOR counts (> or = 4.3) was significantly poorer than survival of those with lower AgNOR counts (< 4.3). Significantly more PCNA positive cells were identified in cancer by immunohistochemical stain and correlated with the presence of mitosis, but there was no significant difference in survival rate groups classified by PCNA positivity. It is also suggested that PCNA can be a useful marker of cell proliferation in prostatic lesions, but the AgNOR counts were diagnostically and prognostically more valuable than immunohistochemical PCNA in prostatic lesions. The correlation between AgNOR and PCNA immunoreactivity was not significant.