Cytogenetic analysis of two species of genus Protosticta from Himachal Pradesh, India

Cytogenetically, out of 262 species, only three species of family Platystictidae has been reported worldwide. Present study has been undertaken to study chromosome complement and its characterization of more species of this family. Cytogenetic analyses of Protosticta sanguinostigma Fraser, 1992 and Protosticta uncata Fraser, 1931 of family Platystictidae, collected from Andretta, Himachal Pradesh, India have been carried out on the basis of conventional staining, C-banding and silver nitrate staining. Both the species possess n=13m as haploid chromosome number and X0-XX sex determining mechanism. One large bivalent is present in all the meiotic stages of P. sanguinostigma which is considered as the species specific character. Chromosome complement of both the species shows variation in distribution of C-bands and Nucleolar organizer regions (NORs). Cytologically, both the species have been described for the first time.

Determination of the relationship among cell proliferation, metabolic activity and stage of pregnancy by AgNORs as markers in bovine placenta / Determinación de la relación entre la proliferación celular, la actividad metabólica y la etapa de preñez por los AgNOR como marcadores en la placenta bovina

SUMMARY: Nucleolus Organizer Regions (NORs) are defined as nucleolar components containing argyrophilic proteins selectively stained by silver methods (AgNORs). Several investigations have shown the AgNOR quantity and area represent a valuable parameter of cell kinetics, since they reflect the level of activity and cellular proliferation. This article addresses an evaluation of the functional activity and relation between days of pregnancy and proliferative capacity of trophoblastic mononucleate and binucleate cells from bovine placentomes. Both the number and size of AgNORs were determined in different phases of gestation by silver nitrate staining in conventional histological slides. The results showed a significant increase (from 1 to 12 AgNORs) in the number of AgNORS per trophoblastic mononucleate cell in the 3rd trimester, with predominance of 4-6 AgNORs/cell. In the 1st and 2nd trimesters, the number ranged between 1 and 9 AgNORs/cell, with predominance of 1-3 AgNORs. No significant differences were observed between the 2nd and 3rd trimesters, but in the first, in binucleate cells (19-27 and 10-18 AgNORs/cell, respectively) - this number was higher than the one registered in trophoblastic mononucleate cells in the same period. Thus, AgNORs can be used as markers of the proliferative placental cell cycle and established a relation between number of AgNORs and days of gestation. This relation can be used for diagnoses and prognoses of several placental pathologies, including pregnancy losses from manipulated embryos.

RESUMEN: Las Regiones Organizadoras de Nucléolos (NOR) se definen como componentes nucleolares que contienen proteínas argirofílicas teñidas selectivamente por métodos de plata (AgNOR). Varias investigaciones han demostrado que la cantidad y el área de AgNOR representan un parámetro importante de la cinética celular, ya que reflejan el nivel de actividad y proliferación celular. Este trabajo analiza la actividad funcional y la relación entre los días de preñez y la capacidad proliferativa de las células trofoblásticas mononucleadas y binucleadas de placentomas bovinos. Tanto el número como el tamaño de los AgNOR se determinaron en diferentes fases de la gestación mediante tinción con nitrato de plata en portaobjetos histológicos convencionales. Los resultados mostraron un aumento significativo (de 1 a 12 AgNOR) en el número de AgNORS por célula mononucleada trofoblástica en el tercer trimestre, con predominio de 4-6 AgNOR / célula. En el primer y segundo trimestre, el número osciló entre 1 y 9 AgNOR / célula, con predominio de 1-3 AgNOR. No se observaron diferencias significativas entre el 2do y 3er trimester; en el primer trimestre, en células binucleadas (19-27 y 10-18 AgNORs / célula, respectivamente) - este número fue superior a la cantidad registrada en células mononucleadas trofoblásticas en el mismo período. Por tanto, los AgNOR se pueden utilizar como marcadores del ciclo celular placentario proliferativo y se establece una relación entre el número de AgNOR y los días de gestación. Esta relación puede ser útil en el diagnóstico y pronóstico de varias patologías placentarias, incluidas las pérdidas de preñeces de embriones manipulados.

Significance of Silver Stained Nucleolar Organiser Region (AgNOR) in Fine Needle Aspiration Smears of Breast Lesions

Background: Breast cancer is the leading cause of cancer - related deaths in Asia. The number of intra-nuclear silver stained structures, termed AgNORs, is significantly higher in malignant cells than in normal, reactive or benign cells. The purpose of this study was to evaluate the AgNOR scores in FNA smears of breast lesions and their correlation with histopathology. Aims & Objective: To establish AgNOR staining as a diagnostic and prognostic tool in management of various breast lesions. Methods: This was a prospective study conducted over a period of 18 months may 2015 to November 2016. A total of 100 cases were included in the study. AgNOR stain was done in both cytology and scoring was done and analysed. Results: In FNAC aspirates, Mean AgNOR count ranged from 5 to 9.9 per high power field with a mean value of 2.888±2.553. The AgNOR dots morphology was homogenous, symmetric with regular contours in FNAC slides of benign breast lesion. In malignant breast lesions, the dots were asymmetric with irregular contours and were aggregated, smaller and more scattered. Conclusions: The present study showed that fine needle aspiration cytology is a useful modality for diagnosis of breast lesions. It has a high concordance with the histopathology . AgNOR count assessment provides a useful objective measure for segregation of different grades of tumor with 100% accuracy for detection of higher grade of lesions, as observed in present study. For differentiation of benign from malignant lesions too it has a high sensitivity as well as specificity. The usefulness of FNAC to evaluate nodal involvement also showed a 90% sensitivity and 95.6% specificity. On the basis of present study, it could be concluded that AgNOR count estimation using fine needle aspiration is a useful method to differentiate and diagnose breast lesions.

Efficacy of argyrophilic nucleolar organizing region analysis using computer‑assisted and manual in oral leukoplakia: A comparative study.

OBJECTIVE: 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. MATERIALS AND METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Interrelation of Argyrophilic Proteins of Nucleolar Organizer Regions and Ki-67 with Clinical and Morphological Parameters and Survival in Patients with Non-small Cell Lung Cancer.

Argyrophilic proteins associated with nucleolar organizer regions (AgNOR) and Ki-67 were studied at non-small cell lung cancer (NSCLC). Tumors with low and high area index (AI) of AgNOR and label index (LI) Ki-67 were defined. AI AgNOR was related to the key clinical and morphological parameters in accordance with TNM system: values Т, N, greatest tumor dimension up to 3 cm and more, disease stage, histogenesis, and tumor differentiation. LI Ki-67 is related to the greatest tumor dimension up to 3 cm and more, disease stage, and tumor differentiation. NSCLC patients survival is longer in low AI AgNOR or LI Ki-67 tumors versus high AI AgNOR or LI Ki-67 tumors. NSCLC patients survival is longer in low AI AgNOR and LI Ki-67, shorter in high AI AgNOR and LI Ki-67, and intermediate in opposite AI AgNOR and LI Ki-67. Value N, greatest tumor dimension, histogenesis, AgNOR are independent predictors in NSCLC. NSCLC patients survival without metastases to lymph nodes is related to the greatest tumor dimension and in case of metastases it is related to AI AgNOR and greatest tumor dimension. Combined determination of AgNOR and Ki-67 has prognostic value at NSCLC.

Quantification of AgNOR expression in exfoliated oral mucosal cells of tobacco chewers with and without lesion.

Background: Nucleolar organizer regions (NOR) are associated with proliferative activity and represent a diagnostic and prognostic marker. Materials and Methods: Smears were taken from smokers, tobacco chewers, oral squamous cell carcinoma patients, and normal subjects and evaluated by 2 silver-staining nucleolar organizer region (AgNOR) counting methods: (1) mean number of AgNORs per nucleus (mAgNOR); and (2) percentage of nuclei with >3 and >5 AgNORs (pAgNOR). Results: A statistically significant difference was observed between normal subjects, smokers, tobacco chewers, and oral cancer patients and between tobacco chewers with and without lesion. No significant difference was observed between tobacco chewers and smokers except in the percentage of >5 criteria. Conclusions: AgNOR enumeration using noninvasive methods, such as the cytobrush appears to be useful technique in distinguishing between normal mucosa, mucosa with and without lesions exposed to carcinogens, such as tobacco and frank oral carcinoma.

Histologic grading and nucleolar organizer regions in oral squamous cell carcinomas

OBJECTIVE: The purposes of this study were to histologically assess different types of oral squamous cell carcinoma and the silver-binding nucleolar organizer region (AgNOR) morphology in neoplastic cells, as well as to quantify the number of AgNORs in each type of carcinoma in order to relate AgNOR count and histologic grading. MATERIAL AND METHODS: Twenty-eight cases of oral squamous cell carcinoma were divided into 4 groups, namely well-differentiated, moderately differentiated, poorly differentiated, and undifferentiated. For NOR study, 3-µm-thick sections were stained with 50 percent aqueous silver nitrate solution. The predominant microscopic pattern of NORs was determined. Quantitative analyses of NORs were obtained of all cells present on each histological field using a 0.025 mm² eyepiece graticule. Different histological fields were analyzed until the total number of NORs was 120 cells for each tumor. Kruskall-Wallis test was applied to compare the groups of sample data at a significance level of p=0.05. RESULTS: The mean number of AgNORs per nucleus was 3.20 for the well-differentiated group, 5.33 for the moderately differentiated one, 8.27 for the poorly differentiated one, and 10.08 for the undifferentiated one. AgNOR count was significantly different (p<0.05) among all of the studied groups. CONCLUSION: AgNOR staining technique seems to be a useful diagnostic tool since differences in AgNOR numeric values can be identified in the different types of oral squamous cell carcinoma. This technique is easy to handle and inexpensive, thus justifying its large use in histopathology.

AgNOR polymorphism association with squamous intraepithelial lesions and invasive carcinoma with HPV infection / Asociación de los polimorfismos AgNORs con lesiones intraepiteliales escamosas, carcinoma cervical e infección por VPH

OBJECTIVE: Evaluate the relationships between AgNORs polymorphisms and squamous intraepithelial lesions (SIL) and squamous cell carcinoma (SCC) with HPV infection. MATERIALS AND METHODS: A study was carried out on sixty women from the state of Guerrero, Mexico. HPV detection was performed by PCR. AgNORs were identified by argentic impregnation. One hundred cells per slide were counted and classified according to the polymorphism of AgNORs dots; typical (spherical) and atypical (large, kidney-shaped and clustered). RESULTS: A total of 100 percent of the cases were positive for HPV infection. Nine different high-risk HPV genotypes were found, type16 was the most common (48.6 percent). The AgNORs showed a significant decrease in spherical shape according to neoplastic development. The three atypical shapes showed a significant increase in SIL and SCC (p-trend<0.001). CONCLUSIONS: AgNORs polymorphism rises progressively according to the grade of histological lesions that can be useful as a prognosis for progression of SCC.

OBJETIVO: Evaluar la relación entre los polimorfismos de AgNORs con las lesiones intraepiteliales escamosas (LIE) y carcinoma de células escamosas (CCE). MATERIAL Y MÉTODOS: Se estudiaron sesenta mujeres del estado de Guerrero, México. La detección del VPH fue por PCR y los AgNORs por impregnación argéntica; se contaron 100 células y se clasificaron por tipo de polimorfismo de AgNORs: típico (esférico) y atípicos (largo, forma de riñón o de racimo). RESULTADOS: El 100 por ciento de los casos presentaron infección por VPH, se encontraron nueve genotipos diferentes de VPH de alto riesgo, el 16 fue el más común (48.6 por ciento). La forma esférica de los polimorfismos de AgNORs mostró una disminución con el desarrollo neoplásico y las atípicas incrementaron progresivamente con SIL y SCC (p-tendencia<0.001). CONCLUSIONES: Los polimorfismos AgNORs se incrementan progresivamente con el grado de lesión histológica, y pueden ser útiles en el pronóstico de progresión del carcinoma cervical.

Relationships among growth and different NOR phenotypes in a specific stock of rainbow trout (Oncorhynchus mykiss)

Growth is one of the most important aspects in the genetic improvement of cultured fish species. Consequently, genetic parameters related to this feature and their response to selection have been the focus of most research in this area. Such research indicates that, in general, there is enough additive genetic variance related to growth, justifying the use of selection. Based on the usefulness of cytogenetic and molecular markers in the fish culture, the aim of the present work was to analyze the possible relationships among cytogenetic characteristics, specifically the NOR phenotypes, and the increase in length and weight in specimens of the rainbow trout (Oncorhynchus mykiss), resultant from directed mating between homozygous females and heterozygous males according to their NOR phenotypic patterns. The equations of the relationship between length and weight of the analyzed specimens followed the model Wt = a Lt b, showing b values higher than 3, determinant of a positive allometric growth. The results showed that the different NOR phenotypes were not related with the growth values for length and weight in any statistical test.

O crescimento é um dos mais importantes aspectos considerados no melhoramento genético de espécies de peixes cultivadas. Conseqüentemente, a ênfase das pesquisas na área tem sido avaliar os parâmetros genéticos relacionados com esta característica e sua resposta à seleção. Essas pesquisas indicam, em geral, haver variância genética aditiva suficiente para justificar o uso da seleção. Considerando que a utilização de marcadores citogenéticos ou moleculares pode ser de grande valia para a piscicultura, o presente trabalho teve como objetivo analisar a possível relação entre as características citogenéticas, de modo específico os padrões fenotípicos das NORs e o crescimento em comprimento e em peso dos exemplares de trutas arco-íris (Oncorhynchus mykiss) resultantes de acasalamentos dirigidos entre fêmeas homozigotas e machos heterozigotos, conforme caracterização do padrão fenotípico da NOR. As equações da relação comprimento e peso dos indivíduos analisados seguiram o modelo onde Wt = a Lt b, mostrando valores de b maiores que 3, determinante de um crescimento do tipo alométrico positivo. Os resultados mostraram que os padrões fenotípicos da NOR dos indivíduos homozigotos e dos heterozigotos não apresentaram diferenças estatisticamente significativas entre seus valores de crescimento em comprimento ou peso.

Significance of Determination of Argyrophilic Proteins in Nucleolar Organizer Regions of Blood T Lymphocytes before and after Complete Remission in Children with Acute Leukemia / 实用儿科临床杂志

Objective To detect the argyrophilic proteins in nucleolar organizer regions(Ag-NORs) that express rDNA and rRNA proliferation of T lymphocytes before chemotherapy and after complete remission(CR) in children with primary acute leukemia(AL).Methods The argyrophilic granules area of NOR/nuclear area(I.S%) of T lymphocytes was detected by image analysis system in peripheral blood of 42 patients before chemotherapy and after CR and 30 normal children.Results I.S% in the patients before chemotherapy(5.06%?1.36%) were significantly lower than those in the healthy donors(7.51%?1.06%)(t=8.238 P0.05).Conclusion These results suggest that decrease of Ag-NORs expresses the evidence for tumour induced suppression of immune function of T cells in children with AL prior to treatment.

The Clinical Study of PCNA and AgNORs in Colorectal Carcinoma and Carcinoma Adjacent Mucosa / 中国普外基础与临床杂志

Objective To study the expression and significance of proliferating cell nuclear antigen (PCNA) and argyrophilia nucleolar organizer regions (AgNORs) in colorectal carcinoma (CRC) and carcinoma adjacent mucosa (CAM).Methods The expression of PCNA in 48 cases of colorectal carcinoma tissue, CAM and 10 cases of normal mucosa was detected by immunohistochemistry techniques. AgNORs was determined with argyrophilia stain. Results The PCNA labeling index (PCNA LI) and AgNORs count in CRC were higher than that in CAM and normal mucosa( P

The Study of Expression of Proliferating Cell Nuclear Antigen(PCNA) and Nucleolar Organizer Regions(NORs) in Transitional Cell Carcinoma of the Urinary Bladder / 대한비뇨기과학회지

The expression of two cell proliferation indices, the proliferating cell nuclear antigen( PCNA), using the monoclonal antibody in the immunoperoxidase method, and the nucleolar organizer regions (NORs), using silver nitrate staining technique, were assessed in formalin-fixed paraffin embedded material of transitional cell urinary bladder carcinomas. The aim of our study was to examine comparatively the expression of PCNA and the number of NORs in 37 transitional cell bladder carcinomas and to investigate how they correlate with tumor grade and the disease stage. It was noticed that the PCNA expression rate(%) related to grade was statistically significant only between grades II and III (p 0.05). The mean number of AgNORs per nucleus between grades I and II and between grades II and III were statistically significant(p<0.05). As far as the correlation of PCNA expression rate(%) with the stage is concerned, PCNA expression rate (%) was higher in the invasive tumors(p<0.05) than in the superficial tumors and AgNOR Numbers was also greater in the invasive tumors(p <0.05). The linear correlation coefficient between PCNA expression rate (%) and AgNOR counts was 0.52(p <0.001) In conclusion, a considerable relationship was found between the histological grade and each of the two indices used. A good correlation was also demonstrated between each of PCNA expression rate(%) and AgNOR scores to the pathologic stage. Our results suggest that PCNA expressionrate( % ) and AgNOR scores may be prognostic induces in urinary bladder cancer.

A Study of AgNORs(Argyrophilic Nucleolar Organizer Regions) on Prediction of the Prognosis in Intracranial Meningiomas

A silver staining technique was used in the study of nucleolar organizer regions(AgNORs) from the paraffin sections of 26 meningiomas. The specimens were divided into four groups as follows:benign(n=16), atypical(n=5), anaplastic or malignant(n=5) and recurrent without atypical histological findings(n=2) groups, and the mean number of AgNORs in each group was 1.47+/-0.27, 1.93+/-0.4, 2.00+/-0.27 and 1.49+/-0.53 respectively. We noted that the mean number of AgNORs reflected the cellular kinetics of a tumor and was related to histological grade. There was no significant difference between non-recurrent & recurrent benign meningiomas and it was thought that the main cause of recurrence in benign meningiomas was not perhaps cell proliferation but incomplete surgical removal.

Prognostic significance of silver-binding nucleolar organizer regions(AgNORs) in prostatic carcinoma: The correlative study with flow cytometric S-phase fraction, proliferation inde and proliferating cell nuclear antigen(PCNA) expression rate / 대한비뇨기과학회지

The nucleolus plays a vital role in control of cell proliferation and protein synthesis. Nucleolar organizer regions (NORs), segment of DNA closely associated with nucleoli, contain coding genes for ribosomal RNA and contribute the regulation of cellular protein synthesis. Detectable by the argyrophilia of associated proteins, silver-binding nucleolar organizer regions (AgNORs) numbers correlate with growth fraction and have been reported the AgNORs counts may have diagnostic and prognostic utility in other human tumors. We investigated further the diagnostic usefulness of the AgNORs technique as a discriminant for malignancy. In addition, we compared the AgNORs counts with flow cytometric analysis of ploidy, S-phase fraction (SPF), proliferation index (PI), and proliferating cell nuclear antigen (PCNA) expression rate. Also, we assessed this technique as a possible prognostic indicator for prostatic carcinoma. There was no linear relationship between the mean number of AgNORs per nucleus versus Gleason histologic grade (r=0.093, p=0.578) and DNA aneuploid group was associated with higher AgNORs counts than diploid group in clinical stage C and D, but the differences were statistically insignificant. The mean number of AgNORs per nucleus had no significant relationship to SPF (r=-0.09, p=0.58) and PI (r=-0.119, p=0.477). Also, there was no significant relationship between mean number of AgNORs and PCNA (r= 0.205, p=0.217). We evaluated the probability, of survival for 29 patients with close follow-up. There was no significant difference of survival between high and low AgNORs number group, even after combined stratification by Gleason grade (Kaplan-Meier analysis with generalized Wil-coxon test). We conclude that this method alone does not offer a reliable histologic discriminanl for malignancy in prostatic tumor, and it is concluded that this technique is of no value in predicting prognosis for prostatic carcinoma.

Clinical significance of silver binding nucleolar organizer regions(AgNORs) in transitional cell carcinoma of the bladder : The correlative study with flow cytometric SPF, PI and PCNA / 대한비뇨기과학회지

Nucleolar organizer regions(NORs) contain coding genes for ribosomal RNA and contribute the regulation of cellular protein synthesis. AgNORs numbers correlate with growth fraction and have been reported the AgNORs counts may have a diagnostic and prognostic utility in other human tumors. We investigated the diagnostic usefulness of AgNORs staining technique as a discriminant for malignancy and assessed the value as a potential method for the estimation of cell kinetics. In addition. we compared the AgNOR counts with flow cytometric analysis of ploidy, S-phase fraction, proliferation index, and PCNA expression rate. There was a statistically significant difference of AgNORs counts between superficial bladder tumor and invasive bladder tumor. But there was no relationship between the mean number of AgNORs per nucleus and histological grade. DNA aneuploid group was associated with higher AgNORs counts than diploid group, but the difference was statistically insignificant. The mean number of AgNORs per nucleus had significant relationship to SPF(r=0.43, p<0.05) and PI(r=0.41, p<0.05.) We concluded that this method alone does not offer a reliable histological discriminant for malignancy. Further studies are needed to confirm that AgNORs counting is a useful method for evaluating the proliferative activity and this technique may serve as a prognostic factor additional to the current histopathological grading criteria of the bladder cancer.

A Study of Nucleolar Organizer Regions in Normal and Neoplastic Epithelial Cells of Stomach

Nucleolar organizer regions are DNA loops encoding rihbosomal RNA production and detectable by the argyrophilia of their associated proteins(AgNORs). AgNOR numbers correlate with cellular proliferating activity. Many studies have shown a significnt difference in AgNOR counts between benign and malignant tumors. AgNOR counts were also helpful in differential diagnosis. For the evaluation of its diagnostic utility in gastric lesions, a silver staining technique was carried out in paraffin sections of 5 control cases, 5 benign peptic ulcers, 7 hyperplastic polyps, 10 tubular adenomas, 16 early gastric adenocarcinomas and 15 advanced gastric adenocarcinomas. The results were as follows. The mean numbers of AgNORs in early and advanced gastric adenocarcinomas(1.94 and 2.16) were significantly higher than those of normal foveolar epithelium(1.43) and epithelia of benign gastric ulcers(1.54), hyperplastic polyps(1.64) and tubular adenomas(1.79). In malignancy, there was increased variability in size and shape of AgNORs. There was little differences in mean AgNOR numbers between early and advanced gastric adenocarcinomas. Differentiation of the tumor made no difference in AgNOR numbers. From the above results, the AgNORs count, if its morphologic change are taken into consideration, is helpful in differentiation between malignant and non-malignant lesions.

The significance of the nucleolar organizer regions(NORs) in prostatic adenocarcinoma / 대한비뇨기과학회지

NORs are loops of DNA which occur in nucleoli and which posses ribosomal DNA genes. Ribosomal DNA genes transcribe to ribosomal RNA by RNA polymerase I and are of vital significance in the ultimate synthesis of protein. Proteins associated with the NORs are stained with silver nitrate (Ag-NORs). Ag-NORs were studied in various tumors and might reflect the activity of cells and might be an indicator of the degree of malignancy in tumors. Specimens of prostate obtained by transurethral resection or fine needle biopsy were examined with regard to the number and area of NORs in order to find out whether the above mentioned two parameters reflect proliferative activity in 23 cases of prostatic adenocarcinoma and 10 cases of benign prostatic hyperplasia as controls. The mean number of Ag-NORs in BPH, well, moderate and poorly differentiated adenocarcinoma was 1.24+/-0.10 (mean+/-SD; n=10), 1.87+/-0.23 (n=6). 2.08 J=0.28 (n=10). 4.02+/-0.22 (n=7). respectively. In each group, significant difference was found statistically (p<0.05) except between well and moderate differentiated adenocarcinoma. The mean area of Ag-NORs calculated by morphometry in BPH, well, moderate and poorly differentiated adenocarcinoma was 5.40+/-1.8 um2, 7.84+/-3.68 um2. 14.02+/-4.95 um2, 23.99+/-6.94 um2, respectively and significant difference was found statistically in each group (p<0.05). We concluded that the number and area of NORs increased with degree of malignancy and may reflect proliferative activity of cells in prostatic adenocarcinoma. Further investigations may be needed to confirm whether the number or area of Ag-NORs may be available as a prognostic factor for patient`s survival.

The significance of nucleolar organizer regions in bladder epithelial lesions induced by N-butyl-N-(4-hydroxybutyl)nitrosamine in rat / 대한비뇨기과학회지

It is known that the activity of tumor cells correlates with the malignant potential of tumors. Nucleolar organizer regions(NORs) are loops of DNA which occur in nucleoli and which possess ribosomal DNA genes. Ribosomal DNA genes transcribe to ribosomal RNA by RNA polymerase I and are of vital significance in the ultimate synthesis of protein. Proteins associated with the NORs are stained with silver nitrate(Ag-NORs). Ag-NORs were studied in various tumors and might reflect the activity of cells and might be and indicator of the degree of malignancy in tumors. 0.05 % N-Butyl-N(4-hydroxybutyl) nitrosamine(BBN) in drinking water was given for 8 and 14 weeks to induce pre-neoplastic and neoplastic vesical epithelial lesions in female Wister rats. Ag-NORs were stained by the simple one-step silver colloid staining in routine processed, formalin-fixed paraffin sections of bladder lesions induced by N-butyl-N(4-hydroxybutyl) nitrosamine(BBN) in rat. The mean number of silver stained NORs(Ag-NORs) was as follows : normal transitional epithelium was 1.64+/-0.25(mean+/-SD; n=10), simple hyperplasia was 2.24+/-0.24(n=7). nodular hyperplasia was 2.63+/-0.12 (n=6), transitional cell papilloma was 3.24+/-0.28(n=6) and transitional cell carcinoma was 4.52+/-0.32(n=10). Based on the above results, we concluded that the mean number of Ag-NORs showed a stepwise increase from normal transitional epithelium through simple hyperplasia and nodular hyperplasia to papilloma and carcinoma of bladder epithelium induced by BBN in rat and may reflect proliferative activity of cells. Further investigations may be needed to confirm whether the number or quantification of Ag-NORs is a useful method for evaluating proliferative activity of neoplastic lesions or another indicator of prognosis in human bladder cancer.

Nucleolar organizer regions in glioma / 영남의대학술지

Nucleolar organizer regions (NOR) are loops of ribosomal DNA (rDNA) which are transcribed by RNA polymerase I. They produce ultimately ribosome and protein. Thus they are believed to reflect nuclear activity. We applied silver colloid staining technique to human glioma to examine relationship between the mean number of Ag-NOR and histopathological grading. The mean number of Ag-NOR (±S. E of the mean) were 1.17±0.07 in normal brain, 1.53±0.25 in astrocytoma, 2.37±0.71 in malignant astrocytoma. And 2.88±0.41 in glioblastoma multiforme. And there was a statistically significant difference among these. The results show that Ag-NOR technique is a rather simple and rapid method and will become a helpful tool for estimation of the proliferative potential of glioma.

Nucleolar Organizer Regions in Normal Tissue and Hyperplastic and Neoplastic Lesions

For the identification of proliferating cells in tissue, the argyrophilic method for the demonstration of nucleolar organizer regions (Ag-NORs) have been described. To evaluate the applicability of Ag-NORs in surgical pathology, the authors have done Ag-NORs staining on 144 cases of routinely processed, formalin-fixed paraffin sections of various tissues; 15 normal tissues, 12 reactive and hyperplastic lesions, 30 benign neoplasms, 4 borderline lesions, and 83 malignant tumors. The results were summerized as follows; 1) In normal tissues, the mean numbers of Ag-NORs were highter in labile cells, especially in actively proliferating cells such as germ cells of testis, crypt epithelial cells in gastrointestinal mucosa, and lymphocytes from germinal center of tonsil and lymph node, than those of stable cells. 2) The mean numbers of Ag-NORs in reactive and hyperplastic lesions, benign neoplasms, and borderline lesions were similar to those of normal labile cells. 3) The mean numbers of Ag-NORs in carcinomas and sarcomas, (usually more than 2) significantly exceeded those of normal and non-malignant conditions. However, certain cases of carcinomas such as papillary carcinomas of thyroid, mucinous carcinoma of stomach, bronchioloalveolar carcinoma of lung, and adenoid cystic carcinoma of lung, and some of the leiomyosarcoma, malignant fibrous histiocytoma, and malignant schwannoma showed relatively lower numbers of Ag-NORs. 4) In non-Hodgkin's lymphomas, the high grade lymphomas showed more Ag-NORs than the low grade ones. From above results, it is suggested that the Ag-NORs technique is helpful in differentiation between malignant and non-malignant lesions. However, further evaluation on the significance of Ag-NORs upon the behavior of the cancer is to be made.