Silver Nitrate Staining Research Articles

Effect on MDA-MB231 human breast cancer cell line treated with bilberry (Vaccinium myrtillus) using Annexin V and AgNOR staining

Background/Aim: Cancer has become a prevalent disease, emerging as one of the major chronic health issues today. Currently, common treatments against cancer include chemotherapy, radiotherapy, surgery, and the use of chemically synthesized drugs. However, despite significant advancements in diagnostic methods and treatments, drug resistance and metastasis remain primary hurdles to successful cancer therapy. Consequently, attention has been shifted towards exploring alternative treatments and therapies against cancer. This study sought to examine the time and dose-dependent effects of blueberry (Vaccinium myrtillus L) on MDA-MB-231 cell lines. Methods: The study used the MDA-MB231 breast cancer cell line. We established three groups: control, 40 µl/ml bilberry, and 80 µl/ml bilberry, which were incubated at 37°C and 5% CO2 for 24 and 48 h, respectively. After incubation, we examined the viability, apoptosis, and cell cycle of MDA-MB-231 cells with the Muse Cell Analyzer and assessed the status of nucleolar organizer region (NOR) proteins via silver nitrate (AgNOR) staining. Results: Bilberry extracts were found to enhance apoptosis and exhibit a cytotoxic effect, thereby reducing cell proliferation in MDA-MB-231 cells after 24 and 48 h of culture. There was notably increased apoptosis at concentrations of 40 µl and 80 µl. Moreover, after 48 h of incubation, a significant difference emerged between the control and 40 µg/ml bilberry samples, notably in the average AgNOR count and the total AgNOR area/total nuclear area ratio. Conclusion: Our study suggests that blueberries may be a potential therapeutic candidate for cancer treatment, thereby potentially enriching cancer research.

Assessment of the genetic polymorphism of genus Pinus L. the oligotrophic peat bog "Boloto Mshana"

Aim. To evaluate the molecular genetic polymorphism of representatives of the genus Pinus L. on the territory of the "Boloto Mshana" nature reserve, as well as to test the hypothesis about their possible local hybridization Methods. DNA extraction using CTAB and DNeasy Plant Pro Kit, polymerase chain reaction (PCR) with primers for the chloroplast DNA and genes encoding β-tubulin (TBP markers), electrophoresis of DNA in a polyacrylamide gel with silver nitrate staining. Results. DNA profiles of P. mugo, P. sylvestris and probably P. uliginosa (21 samples in total) were analyzed using one chloroplast DNA marker and two DNA markers based on introns of β-tubulin genes (ТВР, сТВР). The intraspecific genetic polymorphism of the species was compared and the probability of the existence of hybrid forms was investigated. Conclusions. The marker based on the 2nd intron of the β-tubulin genes turned out to be the most effective and informative DNA marker for studying representatives of the Pinus L. genus. P. sylvestris showed less genetic polymorphism by the investigated genetic markers, compared to P. mugo and P. uliginosa. Possible hybrid forms (P. mugo ✕ P. sylvestris) or P. uliginosa were also discovered.

Cereal barcoding by assessing intron length polymorphism of γ-tubulin genes

Aim. The aim of the study was to obtain typical DNA profiles for common cereal plants using a method of assessing γ-tubulin intron length polymorphism and to evaluate the possibility of using this gene for plant species barcoding. Methods. Cereals, in particular wheat, aegilops, barley, and rice, have been studied. The method of γ-tubulin intron length polymorphism assessment was used. Amplified DNA fragments were separated via polyacrylamide gel electrophoresis under non-denaturating conditions and were visualized via silver nitrate staining. Results. The analyzed cereal species-specific DNA profiles of amplicons of the γ-tubulin gene introns were obtained, which made it possible to differentiate the species. Fingerprinting data was used for cluster analysis and dendrogram construction. Conclusions. The feasibility of using the proposed cereal barcoding method has been established. The studied plant DNA profiles can be effectively used in assessing the quality of food products such as flour.

Investigating the interaction of zno nanoparticles with flagellum and fimbriae in multi-drug resistant uropathogenic bacteria encoding fli and fim genes.

Due to the increasing occurrence of drug resistant urinary tract infections (UTI) among children, there is a need to investigate alternative effective treatment protocols such as nanoparticles. Flagella and fimbriae are primary factors contributing the virulence of urinary tract infecting bacteria. The aim of this study was to assess the antibacterial effects of zinc oxide nanoparticles which have been synthesized using both chemical and green methods on multi-drug resistant (MDR) uropathogenic bacteria encoding fli and fim genes and investigating their binding ability to bacterial appendage proteins. A total of 30 urine culture samples were collected from children under 2 years old diagnosed with urinary tract infection. The isolates underwent antibiotic suseptibility assessment and the isolates demonstrating MDR were subjected to molecular amplification of fimG (fimbrial) and fliD and fliT (flagellal) genes. The confirmation of cellular appendages was achieved through silver nitrate staining. The antibacterial efficacy of the synthetized nanoparticles was assessed using the micro and macrodilution methods. The successful binding of nanoparticles to bacterial appendage proteins was confirmed through mobility shift and membrane filter assays. The dimensions of chemically synthesized ZnO nanoparticles and green nanoparticles were measured at 30nm and 85nm, respectively, with the exhibition of hexagonal geometries. The nanoparticles synthesized through chemical and green methods exhibited minimum inhibitory concentrations (MIC) of 0.0062-0.025g/L and 0.3g/L, respectively. The ability of ZnO nanoparticles to bind bacterial appendage proteins and to combat MDR uropathogenic bacteria are promising for new treatment protocols against UTI in children in future.

Karyotype Variability in Wild Narcissus poeticus L. Populations from Different Environmental Conditions in the Dinaric Alps.

Narcissus poeticus L. (Amaryllidaceae), a facultative serpentinophyte, is a highly variable species and particularly important ancestor of cultivated daffodils, but is rarely studied in field populations. This study, based on natural populations in the Balkans, focused on karyotype variability, genome size, ploidy and the presence of B chromosomes. Thirteen native populations from different environmental and soil conditions were collected and analyzed using flow cytometry to estimate nuclear genome size, fluorescence in situ hybridization (FISH) for physical mapping of rDNA, fluorochrome labeling (chromomycin and Hoechst) for heterochromatin organization and silver nitrate staining of nucleoli for determining rRNA gene activity. The organization of rDNA and natural triploids is reported here for the first time. The presence of individuals with B chromosomes (in 9/13 populations) and chromosomal rearrangements was also detected. The observed B chromosome showed three different morphotypes. The most frequent submetacentric type showed four different patterns, mainly with active ribosomal genes. The results obtained show that N. poeticus has a dynamic genome with variable genome size due to the presence of polyploidy, B chromosomes and chromosomal rearrangements. It is hypothesized that the observed changes reflect the response of the genome to different environmental conditions, where individuals with B chromosomes appear to have certain adaptive advantages.

HTERT gene methylation in circulating DNA, tumor, and surrounding tissue in breast cancer: a prospective study.

The human telomerase reverse transcriptase (hTERT) enzyme, encoded by the hTERT gene, synthesizes protective telomeric sequences on chromosomes and plays a fundamental role in cancer formation. Methylation of the hTERT gene has an upregulatory effect, increasing hTERT enzyme synthesis and allowing continuous tumor cell division. In a group of patients with breast cancer, we aimed to analyze the methylation status of hTERT in the tumor, surrounding tissue, and circulating free deoxyribonucleic acid (cfDNA) of blood collected on the day of mastectomy and then approximately one year later. A prospective study was conducted at a university hospital in Rio de Janeiro, Brazil. Samples were collected from 15 women with breast cancer on the day of mastectomy and approximately one year postoperatively. cfDNA was analyzed by sodium bisulfite conversion, followed by polymerase chain reaction, electrophoresis, and silver nitrate staining. Methylation of hTERT was detected in the tumors and surrounding tissues of all 15 patients. Five patients displayed hTERT methylation in the cfDNA from the blood of the first collection. Of the ten patients who returned for the second collection, three showed methylation. Two patients with methylation in the first collection did not display methylation in the second collection. One patient with no methylation in the first collection displayed methylation in the second collection, and one patient had a diminished level of methylation in the second collection. Only one-third of patients displayed methylation in their cfDNA, which may be related to the success of chemotherapy.

Non-Alcoholic Steatohepatitis and Autoimmune Hepatitis Cirrhosis May Have a Higher Risk of Progression to Hepatocellular Carcinoma

Background: The evaluation of different cell proliferation and apoptosis indicators in cirrhotic tissues caused by different injuries may help recognize the etiology of cirrhosis and the risk of progression to hepatocellular carcinoma. Objectives: This study aimed to measure p53 gene expression and AMPK and pAMPK protein expressions, as well as AgNOR features in cirrhotic tissues associated with five different etiologies in comparison with simple hepatic steatosis and controls. Methods: In this case-control study, AMPK and PAMPK protein expressions, p53 gene expression, and AgNOR features were investigated in 68 cirrhotic liver tissues obtained from patients with NASH (n = 15), HBV/HCV (n = 14), AIH (n = 15), PSC (n = 15), and alcohol toxicity (n = 9) and compared with tissues from individuals with simple steatosis (n = 15) and control subjects (n = 15). Protein and gene expressions were determined using western blotting and quantitative real-time polymerase chain reaction, respectively. Silver nitrate staining was used to assess AgNOR features. Results: Significantly higher levels of AMPK and pAMPK were detected in all cirrhotic tissues compared to controls (P < 0.05). Also, a significantly and simultaneously higher p53 gene expression (P < 0.01) and AgNOR features, including total AgNOR length (TAL) (P < 0.001), total AgNOR number (TAN) (P < 0.01), and total AgNOR area (TAA) (P < 0.01), was detected in the hepatic cirrhotic tissues obtained from patients with PSC, NASH, and AIH. There was a significant positive correlation between p53 gene expression and AgNOR features in cirrhotic tissues (P < 0.01). Conclusions: Increased AMPK and pAMPK protein levels may be a general response to cirrhosis. Cirrhotic patients diagnosed with AIH, PSC, and NASH have a higher risk of progressing to hepatocellular carcinoma than those diagnosed with viral and alcoholic cirrhosis.

Utility and Limitations of TALLYHO/JngJ as a Model for Type 2 Diabetes-Induced Bone Disease.

Type 2 diabetes mellitus (T2DM) increases risk of fractures due to bone microstructural and material deficits, though the mechanisms remain unclear. Preclinical models mimicking diabetic bone disease are required to further understand its pathogenesis. The TALLYHO/JngJ (TH) mouse is a polygenic model recapitulating adolescent-onset T2DM in humans. Due to incomplete penetrance of the phenotype ~25% of male TH mice never develop hyperglycemia, providing a strain-matched nondiabetic control. We performed a comprehensive characterization of the metabolic and skeletal phenotype of diabetic TH mice and compared them to either their nondiabetic TH controls or the recommended SWR/J controls to evaluate their suitability to study diabetic bone disease in humans. Compared to both controls, male TH mice with T2DM exhibited higher blood glucose levels, weight along with impaired glucose tolerance and insulin sensitivity. TH mice with/without T2DM displayed higher cortical bone parameters and lower trabecular bone parameters in the femurs and vertebrae compared to SWR/J. The mechanical properties remained unchanged for all three groups except for a low-energy failure in TH mice with T2DM only compared to SWR/J. Histomorphometry analyses only revealed higher number of osteoclasts and osteocytes for SWR/J compared to both groups of TH. Bone turnover markers procollagen type 1 N-terminal propeptide (P1NP) and tartrate-resistant acid phosphatase (TRAP) were low for both groups of TH mice compared to SWR/J. Silver nitrate staining of the femurs revealed low number of osteocyte lacunar and dendrites in TH mice with T2DM. Three-dimensional assessment showed reduced lacunar parameters in trabecular and cortical bone. Notably, osteocyte morphology changed in TH mice with T2DM compared to SWR/J. In summary, our study highlights the utility of the TH mouse to study T2DM, but not necessarily T2DM-induced bone disease, as there were no differences in bone strength and bone cell parameters between diabetic and non-diabetic TH mice. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

A comparative evaluation of microleakage in three different luting agents used for posterior full metal crown: An in vitro study

The purpose of the study was to evaluate and compare the microleakage at the margins of nickel – chromium full metal crowns cemented with Zinc Phosphate cement, glass ionomer cement. And resin cement.: thirty freshly extracted human molars were selected for the study. Standardized tooth preparation is done with the help of customized metal zig attached to dental surveyor. On prepared teeth castings were fabricated and devided into three groups for the three luting agents namely zinc phosphate cement – Harvard, Glass ionomer cement – Ketac Cem and Resin cement – Rely X U200, each containing 10 samples. After cementation the cemented specimens were stored in artificial saliva for 24 hours. The teeth were then thermocycled between 5°C and 50°C and then treated with 50% silver nitrate stain for 60 minutes. Samples were placed under 150 watt flood lamp for 5 minutes to allow proper fixation of unfixed stain. Then they were embedded in clear acrylic resin and sectioned twice longitudinally. The sections were observed under the stereomicroscope and stain penetration were recorded at tooth cement interfaces. The readings were tabulated and analyzed statistically using Mann-Whitney U test and Kruskal-Wallis H test. .Zinc phosphate cement showed significantly maximum microleakage as compared to glass ionomer cement and resin cement. Resin cement showed significantly less microleakage as compared to glass ionomer cement and zinc phosphate cement. Glass ionomer cement showed more microleakage as compared to resin cement but less as compared to zinc phosphate cement

A New Record of Reduced Chromosome Number in Tenebrionidae (Coleoptera)

The karyological features of Akis subtricostata was determined for the first time with conventional and silver nitrate staining. The diploid number 2n=16 and meioformula 7+neoXY represents a deviation from the modal karyotype of Coleoptera. The pericentromeric heterochromatin was detected with both Giemsa and silver nitrate staining. In addition to determining a single possible NOR on prophase I nuclei, AgNO3 revealed that several telomeric regions of mitotic metaphase chromosomes were slightly more argyrophilic.

Abstract 1489: Overexpression of ribosomal L22-like1 (RPL22L1) enhances cancer stem cell properties and promotes tumor progression in hepatocellular carcinoma (HCC)

Abstract The abnormality of ribosomal biogenesis is found to be involved in carcinogenesis and progression in various types of cancer. RPL22L1 gene is a highly homologous paralog of RPL22, both of which belong to the L22E family of ribosomal proteins and take part in encoding a cytoplasmic ribosomal protein that is a component of the 60S subunit of ribosomes. Our previous work has established a CRISPR/Cas9 genome-wide knockout screening profile and developed a two-component mixture model to identify cancer-specific essential genes in 436 cancer cell lines. Bioinformatics analysis reveals that RPL22L1 acts as a feature gene to predict cancer-specific essential genes in human cancer. Previous studies suggest that RPL22L1 is correlated with tumor progression and adverse prognosis in several cancer types, while its role in hepatocellular carcinoma (HCC) is unknown. In the present study, we found that RPL22L1 is highly expressed in embryonic stem cells (ES) and liver progenitor cells, which were acquired from a vitro hepatic differentiation model originating from ES cells. Hence, we hypothesized that RPL22L1 enhances cancer stem cell properties in HCC. Functional assays showed that RPL22L1 would promote sphere formation in vitro. qRT-PCR and Western Blotting results indicated that RPL22L1 could promote stemness-related gene expressions such as CD133, CD44, and SOX9 in HCC cell lines. Overexpression of RPL22L1 increased aldehyde dehydrogenase (ALDH) activity, which was decreased when RPL22L1 was silenced with short hairpin RNA (shRNA). Extreme limiting dilution assay showed that RPL22L1 overexpression stimulated self-renewal ability in immunodeficient mice. Furthermore, higher RPL22L1 expression can also promote cell proliferation and epithelial-mesenchymal-transition, as well as drug resistance to 5-Fluorouracil (5-FU) and cisplatin (CDDP). Silver nitrate staining demonstrated that RPL22L1 overexpression correlated with a larger size and number of nucleoli. The expression of RPL22L1 was also associated with adverse prognosis in HCC clinical samples. In conclusion, our study reveals aberrant ribosomal protein activity in HCC and the role of RPL22L1 in promoting HCC tumor progression. Citation Format: JinLin Huang, Zhenyang Guo, Jie Luo, Beilei Liu, Lanqi Gong, Xiaona Fang, Dora Lai-wan Kwong, Xinyuan Guan. Overexpression of ribosomal L22-like1 (RPL22L1) enhances cancer stem cell properties and promotes tumor progression in hepatocellular carcinoma (HCC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1489.

Electromagnetic Field Effect on Bone Marrow Stem Cells Differentiation and Nucleoli AgNOR

Purpose: Numerous studies have described the effect of Electromagnetic Fields (EMFs) in the promotion of Bone Marrow Stem Cell (BMSC) differentiation. We aimed to investigate the influence of frequency (10 and 100 Hz) and different pulse shapes (sine, rectangular, and triangular) of EMF on rats' BMSCs.
 Materials and Methods: The BMSCs in 6 groups were exposed to EMF for 1 h/ 7 days. The BMSCs viability was estimated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test. The cresyl violet labeled the Nissl bodies, and the silver nitrate staining was done to evaluate the BMSCs nucleoli AgNORs.
 Results: The MTT test verified that EMF and pulse shape did not affect cell viability. In Nissl bodies staining most of the large neurons were related to the rectangular 10 Hz EMF group. The majority of the differentiated BMSCs were astrocytes, microglia, and oligodendrocyte in the triangular 100 Hz EMF group. Although the silver nitrate staining confirmed the effect of 10 Hz EMF, pulse shape alteration did not affect AgNOR parameters. In conclusion, we presented a low-magnetic flux density EMF (400 µT) to assess the responses of BMSCs nuclei.
 Conclusion: The findings showed that BMSCs differentiation was frequency-dependent. Further investigations are recommended for recognizing the function of EMF on BMSCs.

Targeted postnatal knockout of Sclerostin using a bone-targeted adeno-associated viral vector increases bone anabolism and decreases canalicular density.

The creation of murine gene knockout models to study bone gene functions often requires the resource intensive crossbreeding of Cre transgenic and gene-floxed strains. The developmental versus postnatal roles of genes can be difficult to discern in such models. For example, embryonic deletion of the Sclerostin (Sost) gene establishes a high-bone mass phenotype in neonatal mice that may impact on future bone growth. To generate a postnatal skeletal knockout of Sost in adult mice, this study used a single injection of a bone-targeted recombinant adeno-associated virus (rAAV) vector. 8-week-old Sostflox/flox mice were injected with saline (control) or a single injection containing 5×1011 vg AAV8-Sp7-Cre vector. Ai9 fluorescent Cre reporter mice were dosed in parallel to confirm targeting efficiency. After 6weeks, detailed bone analysis was performed via microCT, biomechanical testing, and bone histology on vertebral and long bone specimens. The AAV8-Sp7-Cre vector induced widespread persistent recombination in the bone compartment. Regional microCT analyses revealed significant increases in bone with vector treatment. In the L3 vertebrae, Sostflox/flox:AAV-Cre showed a 22% increase in bone volume and 21% in trabecular bone fraction compared to controls; this translated to a 17% increase in compressive strength. In the tibiae, Sostflox/flox:AAV-Cre led to small but statistically significant increases in cortical bone volume and thickness. These were consistent with a 25% increase in mineral apposition rate, but this did not translate into increased four-point bending strength. Ploton silver nitrate stain on histological sections revealed an unexpected increase in canalicular density associated with Sost ablation. This report demonstrates a proof-of-concept that the AAV8-Sp7-Cre vector can efficiently produce postnatal skeletal knockout mice using gene-floxed strains. This technology has the potential for broad utility in the bone field with existing conditional lines. These data also confirm an important postnatal role for Sost in regulating bone homeostasis, consistent with prior studies using neutralizing Sclerostin antibodies, and highlights a novel role of Sost in canalicular remodeling.

Studies on Histology, Histochemistry and Micrometry of Hippocampus of Goat (Capra hircus)

The brain of six adult goats was collected for the study of hippocampus. Harris’ Haematoxylin and Eosin (H&E) staining method was used for general microscopic structure of the hippocampus. Aldehyde-Thionin-PAS method was utilized for Nissl’s substance and mucopolysaccharides. Vogt’s method was used for nerve cells, Sevier-Munger method for neural tissues and the micrometry of hippocampus was performed for various layers of cornu ammonis and dentate gyrus. The mean values of thickness of different layers of cornu ammonis were measured by micrometry. Microscopic study revealed that the hippocampus was consisting of six layers, viz., alveus, stratum oriens, stratum pyramidale, stratum radiatum, stratum lacunosum and stratum moleculare. The hippocampus commissure and the dentate gyrus showed PAS positive reaction. Furthermore, these structures also showed a positive reaction with silver nitrate staining (Sevier-Munger staining). The study revealed that almost all the fibres of hippocampus were myelinated.

Silver Nitrate Staining of Nucleolar Organizer Regions (Ag-NORs) in Plant Chromosomes.

Silver nitrate staining to evidence the location of nucleolar organizer regions (Ag-NORs) in chromosomes is widely used as a classical method in plant cytogenetics. Here, we present the most used procedures and highlight some aspects in terms of their replicability by plant cytogeneticists. Some technical features described are materials and methods used, procedures, protocol modifications, and precautions in order to obtain positive signals. The methods to obtain Ag-NOR signals have different degrees of replicability, but do not require any sophisticated technology or equipment for their application.

Nucleolar number variation in Fritillaria (liliaceae) taxa from Greece

The current study aims to estimate the most frequent number of nucleoli in taxonomically interesting Fritillaria species. Silver nitrate staining is applied using a modified protocol in 14 taxa and one hybrid from 17 populations from Greece. This is the first report of the number of nucleoli for all the Fritillaria taxa studied here. In general, the number of nucleoli ranges from 0-8, with Fritillaria pontica and F. theophrasti characterised by the greatest number of observed nucleoli. The results reinforce the classification of taxonomically intriguing taxa, such as Fritillaria sporadum and F. theophrasti, as distinct species, even though they have recently been considered synonyms of F. ehrhartii and F. pontica, respectively.

Comparison of methods of DNA extraction from herbarium specimens of little-pod false flax (Camelina microcarpa Andrz. Ex Dc.)

Aim. The aim of this research was to compare the efficiency of DNA isolation methods from herbarium specimens of Camelina microcarpa Andrz. Ex DC., further modification of these methods to increase DNA yield, and determine the method that would provide the best yield of isolated DNA. Methods. Modifications of the DNA isolation methods using the DNeasy Plant Mini Kit (QIAgen) and the CTAB method were used. PCR was performed using degenerate primers for method of β-tubulin intron length polymorphism (TBP). Amplicons were fractionated in polyacrylamide gel followed by visualization by silver nitrate staining. Results. DNA was successfully extracted from C. microcarpa herbarium specimens sampled with leaf parts and seeds, using the modified by CTAB method, and four modified methods using DNeasy Plant Mini Kit (QIAgen). Conclusions. The study revealed that the most effective method tested was the DNeasy Plant Mini Kit (QIAgen) No. 2. Prolongation of the cell lysis stage had the best effect on the increase of DNA yield. We found that the success of DNA isolation was influenced not so much by the age of the herbarium specimen as by the methods of drying and storing the plants in the collection.

Could Argyrophilic Nucleolar Organizer Regions count mirror DNA Ploidy in Malignant Salivary Gland Tumors?

Objective:Nucleolar organizer regions (NORs) are DNA coils that transcribe to ribosomal RNA. The NOR-associated protein, termed argyrophilic NOR (AgNOR), was visible within the nucleus by staining with silver nitrate examination via the light microscope. AgNOR counting is a proliferation marker and may help in the diagnosis and prognosis of various neoplastic lesions. Aneuploidy (abnormal DNA content) can predict the progression, survival and prognosis of the tumors. The aim of this study was to evaluate the role of AgNORs, DNA ploidy status, and total S-phase fraction (TSPF) as prognostic parameters in malignant salivary gland tumors (MSGTs). Methods:The current study is a retrospective study on a cohort of MSGTs (N=47), to assess AgNORs using Silver Nitrate stain, DNA index (DI), and TSPF using flow cytometry (FCM). Data including tumor size and site, lymphovascular invasion (LVI), lymph node metastasis (LNM) were collected. Results:The AgNORs count was statistically significant with MSGT type. DI was found to have a significant association with tumor site, tumor size and MSGT type. In addition, TSPF was found to be significantly associated with LVI. A moderate positive correlation was noted between AgNORs count and TSPF. LNM, tumor site, high AgNORs and low DI were all associated with short disease-free survival (DFS) and poor overall survival (OS). Conclusion:The present study revealed that high AgNORs count, DNA aneuploidy and TSPF had a poor influence on MSGTs prognosis.

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.

The Fibrillin-1/VEGFR2/STAT2 signaling axis promotes chemoresistance via modulating glycolysis and angiogenesis in ovarian cancer organoids and cells.

BackgroundChemotherapy resistance is a primary reason of ovarian cancer therapy failure; hence it is important to investigate the underlying mechanisms of chemotherapy resistance and develop novel potential therapeutic targets.MethodsRNA sequencing of cisplatin‐resistant and ‐sensitive (chemoresistant and chemosensitive, respectively) ovarian cancer organoids was performed, followed by detection of the expression level of fibrillin‐1 (FBN1) in organoids and clinical specimens of ovarian cancer. Subsequently, glucose metabolism, angiogenesis, and chemosensitivity were analyzed in structural glycoprotein FBN1‐knockout cisplatin‐resistant ovarian cancer organoids and cell lines. To gain insights into the specific functions and mechanisms of action of FBN1 in ovarian cancer, immunoprecipitation, silver nitrate staining, mass spectrometry, immunofluorescence, Western blotting, and Fӧrster resonance energy transfer‐fluorescence lifetime imaging analyses were performed, followed by in vivo assays using vertebrate model systems of nude mice and zebrafish.ResultsFBN1 expression was significantly enhanced in cisplatin‐resistant ovarian cancer organoids and tissues, indicating that FBN1 might be a key factor in chemoresistance of ovarian cancer. We also discovered that FBN1 sustained the energy stress and induced angiogenesis in vitro and in vivo, which promoted the cisplatin‐resistance of ovarian cancer. Knockout of FBN1 combined with treatment of the antiangiogenic drug apatinib improved the cisplatin‐sensitivity of ovarian cancer cells. Mechanistically, FBN1 mediated the phosphorylation of vascular endothelial growth factor receptor 2 (VEGFR2) at the Tyr1054 residue, which activated its downstream focal adhesion kinase (FAK)/protein kinase B (PKB or AKT) pathway, induced the phosphorylation of signal transducer and activator of transcription 2 (STAT2) at the tyrosine residue 690 (Tyr690), promoted the nuclear translocation of STAT2, and ultimately altered the expression of genes associated with STAT2‐mediated angiogenesis and glycolysis.ConclusionsThe FBN1/VEGFR2/STAT2 signaling axis may induce chemoresistance of ovarian cancer cells by participating in the process of glycolysis and angiogenesis. The present study suggested a novel FBN1‐targeted therapy and/or combination of FBN1 inhibition and antiangiogenic drug for treating ovarian cancer.