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Epidemiology of fungal infections: the promise of molecular typing.

As the incidence of invasive fungal disease-particularly nosocomial candidal infection-has increased significantly over the past two decades, molecular typing has become increasingly important for the development of rational infection-control measures and therapeutic strategies. Numerous molecular methods have been used to subtype Candida species, including restriction endonuclease analysis of genomic DNA, Southern hybridization analysis, pulsed-field gel electrophoresis, and polymerase chain reaction-based approaches. Increasingly, typing techniques are being applied to other fungal organisms as well. Although an ideal epidemiological typing technique applicable to a wide range of fungal pathogens is not yet available, several molecular-typing methods may permit rapid, simple, and sensitive discrimination of specific strains among the most clinically important species of fungi.

Aspergillus↗

From the National Institutes of Health. Summary of a meeting on the origin of pandemic influenza viruses.

Influenza type A virus periodically undergoes major antigenic shifts in which the hemagglutinin (HAG) and sometimes the neuraminidase (NA) antigens are replaced by HAG and NA antigens of another subtype. Three such shifts have taken place since the virus was first isolated, and all appear to have occurred in China. The way in which these "new" influenza type A viruses suddenly appear (or reappear) in the human population is not known. At a meeting held in Beijing, China, on November 10-12, 1982, participants discussed the latest findings on the molecular biology of influenza viruses and on aspects of their ecology that may offer insight into the factors responsible for the origin of pandemic influenza viruses. Information obtained in earlier studies has provided some clues about how the antigenic shifts may occur. For example, the H3N2 virus has been found to be a recombinant deriving seven of its eight genes from an H2N2 strain and gene 4 (which encodes for the HAG) from some other virus, possibly an avian influenza virus of the H3 subtype [1-3]. In addition, studies of the genome of the H1N1 virus that appeared in Anshan, China, in 1977 have shown that this virus almost certainly underwent no replication for 27 years. This finding suggests that the virus existed in an animal reservoir during this period [4, 5].

Animals↗

Artificial intelligence in kidney cancer: a review of clinical applications across the disease spectrum.

PURPOSE OF REVIEW: This review examines recent advances (2024-2025) in the application of artificial intelligence (AI) to kidney cancer diagnosis, prognosis, and treatment planning. It categorizes studies across 13 clinical scenarios to assess where AI offers the most clinical utility. RECENT FINDINGS: AI models have demonstrated strong performance in a range of tasks including tumor grading, subtype classification, survival prediction, and risk stratification. Integration of radiomics, genomics, and histopathology has enabled personalized, noninvasive, and timely decision-making. The highest-performing models used CT-based radiomics, particularly for predicting progression-free and recurrence-free survival. However, performance varies across tasks and tumor subtypes, with lower accuracy in detecting oncocytomas or benign vs. malignant differentiation. AI applications in metastatic and nonresected cases remain underexplored, and ultrasound remains a largely under researched modality. While some models improve diagnostic accuracy and workflow efficiency, broader validation across diverse populations is still needed. SUMMARY: AI is transforming kidney cancer care across multiple clinical stages. Although promising, real-world implementation demands ongoing validation and postdeployment monitoring to prevent performance degradation due to distributional drift. AI's integration with multimodal data offers substantial potential to improve outcomes and reduce overtreatment.

Humans↗

Comparison of Staphylococcus aureus isolates from bovine and human skin, milking equipment, and bovine milk by phage typing, pulsed-field gel electrophoresis, and binary typing.

Staphylococcus aureus isolates (n = 225) from bovine teat skin, human skin, milking equipment, and bovine milk were fingerprinted by pulsed-field gel electrophoresis (PFGE). Strains were compared to assess the role of skin and milking equipment as sources of S. aureus mastitis. PFGE of SmaI-digested genomic DNA identified 24 main types and 17 subtypes among isolates from 43 herds and discriminated between isolates from bovine teat skin and milk. Earlier, phage typing (L. K. Fox, M. Gershmann, D. D. Hancock, and C. T. Hutton, Cornell Vet. 81:183-193, 1991) had failed to discriminate between isolates from skin and milk. Skin isolates from humans belonged to the same pulsotypes as skin isolates from cows. Milking equipment harbored strains from skin as well as strains from milk. We conclude that S. aureus strains from skin and from milk can both be transmitted via the milking machine, but that skin strains are not an important source of intramammary S. aureus infections in dairy cows. A subset of 142 isolates was characterized by binary typing with DNA probes developed for typing of human S. aureus. Typeability and overall concordance with epidemiological data were lower for binary typing than for PFGE while discriminatory powers were similar. Within several PFGE types, binary typing discriminated between main types and subtypes and between isolates from different herds or sources. Thus, binary typing is not suitable as replacement for PFGE but may be useful in combination with PFGE to refine strain differentiation.

Animals↗

Type II gonadotrophin-releasing hormone (GnRH-II) in reproductive biology.

Humans may be particularly unusual with respect to the gonadotrophin-releasing hormone (GnRH) control of their reproductive axis in that they possess two distinct GnRH precursor genes, on chromosomes 8p11-p21 and 20p13, but only one conventional GnRH receptor subtype (type I GnRH receptor) encoded within the genome, on chromosome 4. A disrupted human type II GnRH receptor gene homologue is present on chromosome 1q12. The genes encoding GnRH ligand precursors and GnRH receptors have now been characterized in a broad range of vertebrate species, including fish, amphibians and mammals. Ligand precursors and receptors can be categorized into three phylogenetic families. Members of each family exist in primitive vertebrates, whereas mammals exhibit selective loss of ligand precursor and receptor genes. One interpretation of these findings is that each ligand-cognate receptor family may have evolved to fulfil a separate function in reproductive physiology and that species-specific gene inactivation, modification or loss may have occurred during evolution when particular roles have become obsolete or subject to regulation by a different biochemical pathway. Evidence in support of this concept is available following the characterization of the chromosomal loci encoding the human type II GnRH receptor homologue, a rat type II GnRH receptor gene remnant (on rat chromosome 18) and a mouse type II GnRH ligand precursor gene remnant (on mouse chromosome 2). Whether type I GnRH and type II GnRH peptides elicit different signalling responses in humans by activation of the type I GnRH receptor in a cell type-specific fashion remains to be shown. Recent structure-function studies of GnRH ligands and GnRH receptors and their expression patterns in different tissues add further intrigue to this hypothesis by indicating novel roles for GnRH such as neuromodulation of reproductive function and direct regulation of peripheral reproductive tissues. Surprises concerning the complexities of GnRH ligand and receptor function in reproductive endocrinology should continue to emerge in the future.

Amino Acid Sequence↗

The clinicopathological features of anaplastic large cell lymphomas expressing p80NPM/ALK.

The classification of malignant lymphoma has been based on morphological and immunophenotypical findings for a long time. Recently, as chromosomal and genomic abnormalities which closely relate to the specific subtypes of lymphoma are revealed, these factors becoming much more important in the evaluation of differences in clinicopathological features of the various lymphoma subtypes. Anaplastic large cell lymphoma (ALCL) is a subtype of non-Hodgkin's lymphoma (NHL) involving large CD30+ neoplastic cells, which occasionally carries the chromosomal translocation t(2;5)(p23;q35). We have recently found a novel hyperphosphorylated 80-kDa protein tyrosine kinase, p80 which is expressed specifically in human ALCLs with this translocation. Subsequent cDNA cloning showed p80 to be a fusion protein of two genes, the novel tyrosine kinase gene and the nucleophosmin gene, in accordance with the sequence of the NPM/ALK gene. In order to clarify the clinicopathologic features of p80-carrying ALCLs, we developed an anti-p80 polyclonal antibody, which immunoprecipitated, immunoblotted and immunostained p80 specifically. When paraffin sections of 105 cases of ALCL were stained using the anti-p80 antibody, 30 were shown to be p80 positive Clinicopathological comparison between p80-positive and p80-negative ALCLs revealed that the p80-positive cases occurred in a much younger patient age group and that the patients showed a far better 5-year survival rate. These data suggest that p80-positive ALCL is a distinct entity and should be differentiated from p80-negative ALCL.

Age of Onset↗

[Prevalence of Borrelia burgdorferi sensu lato species among patients in the Czech Republic; direct sequencing analysis and real-time polymerase chain reaction].

The spread of borreliosis depends on geographical, environmental and climatic factors as well as on the pathogenesis of the causative agent of the group of Borrelia burgdorferi sensu lato. The rise in the incidence of the disease and emergence of new symptoms are of concern. Relationships between genospecies and symptoms, their geographical spread and possible interference of other pathogens are the subject of the present study. Eighty-seven patients with borreliosis from Central and Eastern Bohemia and Moravia were enrolled in the study. Forty-nine patients of group 1 showed clinical positivity, 21 patients of group 2 tested positive at PCR screening and 17 patients of group 3 were culture positive. Forty-eight patients and 17 isolated strains showed positivity for plasmids and the Borrelia burgdorferi sensu lato genome in conventional nested PCR. Borrelial genotypes and subtypes were detected by direct sequencing of OspA and OspC products. Quantitative data were determined from specific product melting temperature curves for real time PCR. Based on sequencing of the OspA gene, B. garinii (subtypes 6, 5, 4 and 3), B. burgdorferi s.s. and B. afzelii were detected in 14 (51.8%), 8 (29.6%) and 5 (18.5%) out of 27 Central Bohemian patients, respectively. Eastern Bohemian patients showed predominance of B. garinii subtype 5 and co-infection with Anaplasmaphagocytophilum in 7.6%. The predominant causative agent in 25 Moravian patients was B. afzelii (11 patients, i.e. 44%), followed by B. burgdorferi s.s. (9 patients, 36%) and B. garinii 5 patients, i.e. 20%). Sequences of two hypervariable regions of the OspA and OspC genes and distances in phylogenetic trees showed differences not only between genospecies and subtypes but also between wild strains detected by direct sequencing from patient specimens and in vitro cultured strains. The greatest differences were found for patients with long-term borrelial infection.

Antigens, Bacterial↗

Salmonella Enteritidis phage type 21 outbreak in Austria, 2005.

We report an outbreak of gastroenteritis due to Salmonella Enteritidis PT 21 associated with attending an annual traditional fair in a small Austrian village on 4 May 2005. The outbreak lasted from 4 to 8 May. Descriptive and analytical epidemiological investigations were conducted in order to determine the extent of the outbreak and to identify outbreak risk factors. Of the 115 persons who visited the fair, 85 persons fulfilled the criteria of an outbreak case (attack rate = 73.9%). Stool specimens from 52 patients, including two kitchen staff, were tested for salmonella, and 20 specimens were positive for Salmonella Enteritidis PT 21. The cohort study revealed mixed salad (which included potatoes) as the likely cause of the outbreak (RR: 10.4, 95%CI 2.8 - 39.1; P = < 0.001). The causative agent of the outbreak was cultured from the stock of eggs used at the fair and from all three drag swabs and one barn dust sample collected from the responsible egg laying flock. Molecular subtyping by pulsed-field gel electrophoresis of genomic DNA after XbaI digestion showed that isolates from eggs, from the flock and from humans were indistinguishable. We hypothesise that cross contamination from eggs to boiled potatoes occurred in the kitchen area, where raw eggs were handled by village residents preparing a traditional Viennese egg dressing. Unrefrigerated storage of peeled potatoes may have favoured bacterial growth. Eggs from small rural flocks of laying hens kept in a traditional 'natural' way should not be assumed to be salmonella-free.

Adolescent↗

Evidence of intratypic recombination in natural populations of hepatitis C virus.

Hepatitis C virus (HCV) has high genomic variability and, since its discovery, at least six different types and an increasing number of subtypes have been reported. Genotype 1 is the most prevalent genotype found in South America. In the present study, three different genomic regions (5'UTR, core and NS5B) of four HCV strains isolated from Peruvian patients were sequenced in order to investigate the congruence of HCV genotyping for these three genomic regions. Phylogenetic analysis using 5'UTR-core sequences found strain PE22 to be related to subtype 1b. However, the same analysis using the NS5B region found it to be related to subtype 1a. To test the possibility of genetic recombination, phylogenetic studies were carried out, revealing that a crossover event had taken place in the NS5B protein. We discuss the consequences of this observation on HCV genotype classification, laboratory diagnosis and treatment of HCV infection.

5' Untranslated Regions↗

Clinical and genomic characterization of Influenza A co-infection with SARS-CoV-2 and Influenza B: a respiratory surveillance study in Assam, India.

Influenza and SARS-CoV-2 are the primary contributors to seasonal respiratory infections and frequently co-circulate, creating significant health challenges. The present respiratory surveillance study was conducted in Dibrugarh, Assam, India from January 2025&#xa0;to August 2025 to investigate the genomic characteristics of circulating viruses and identify potential co-infections. Overall, 4,948 respiratory samples were screened using multiplex real-time PCR, followed by subtyping of Influenza A and Influenza B. Next-generation sequencing (NGS) was performed in selected positives of SARS-CoV-2 and Influenza A. Genomic analysis included mutational profiling, phylogenetic analysis and N-glycosylation site prediction using bioinformatics tools. Two co-infection cases were detected: one involving Influenza A (H3N2) with SARS-CoV-2 (Omicron XFG lineage) and another involving Influenza A (H3N2) with Influenza B (Victoria lineage). Both patients experienced mild illness without hospitalisation. NGS revealed that the Influenza A (H3N2) viruses belonged to clade 3C.2a1b.2a.2a.3a.1 while SARS-CoV-2 sequence was classified under the Omicron XFG lineage. Mutational analysis of the HA gene showed several amino acid differences compared to the reference vaccine strain A/Darwin/6/2021. N-glycosylation analysis predicted conserved sites at positions 79, 181, 262, and 301 in all strains along with an additional predicted site at position 110 in both co-infection cases. Although the co-infection cases presented with mild clinical manifestations, the observed genomic variations indicate a potential role of co-infecting viruses in shaping viral evolution. Given the limited genomic data available from Northeast India, the study underscores the need for sustained large scale follow up and genomic surveillance to monitor emerging mutations and target future vaccine strategies.

Humans↗

Cloning of minisatellite-containing sequences from two-dimensional DNA fingerprinting gels reveals the identity of genomic alterations in low-grade gliomas of different patients.

Two-dimensional (2-D) DNA fingerprinting was used to investigate genomic changes in human low-grade gliomas of different subtypes. DNA variations were identified in the 2-D hybridization patterns as spot losses or gains. Computer-aided matching of spot patterns from different patients revealed a clustering of spot changes at particular areas in the gel. Representative spots of each cluster were cloned using a spot cloning protocol which includes the preparation of a duplicate and a master gel. The DNA fragments of the 2-D gels were transferred to DEAE and nylon membrane, respectively. After hybridization of the master blot with a minisatellite core probe, the position of a particular spot was determined with reference to the lambda DNA fragments used as external markers in both gels. The gel spot DNA was recovered from the DEAE membrane by high salt elution and was polymerase chain reaction (PCR)-amplified after ligation of adaptor oligo cassettes. The PCR products were cloned and used as locus-specific probe for the rehybridization of the 2-D blots. One of these probes detected a spot loss in 7 of 28 low-grade gliomas of different subtypes analyzed. Another probe revealed a characteristic intensity shift in 8 of 9 pilocytic astrocytomas between two neighboring spots. The target sequence of this highly specific effect was assigned to chromosome 11q14 by in situ hybridization of a P1 clone harboring the affected genomic region. Thus, we successfully established a spot cloning procedure for the generation of locus-specific probes that may be instrumental in the discovery of the critical early events of glioma pathogenesis.

Chromosome Mapping↗

Genome wide measurement of DNA copy number changes in neuroblastoma: dissecting amplicons and mapping losses, gains and breakpoints.

In the past few years high throughput methods for assessment of DNA copy number alterations have witnessed rapid progress. Both 'in house' developed BAC, cDNA, oligonucleotide and commercial arrays are now available and widely applied in the study of the human genome, particularly in the context of disease. Cancer cells are known to exhibit DNA losses, gains and amplifications affecting tumor suppressor genes and proto-oncogenes. Moreover, these patterns of genomic imbalances may be associated with particular tumor types or subtypes and may have prognostic value. Here we summarize recent array CGH findings in neuroblastoma, a pediatric tumor of the sympathetic nervous system. A total of 176 primary tumors and 53 cell lines have been analyzed on different platforms. Through these studies the genomic content and boundaries of deletions, gains and amplifications were characterized with unprecedented accuracy. Furthermore, in conjunction with cytogenetic findings, array CGH allows the mapping of breakpoints of unbalanced translocations at a very high resolution.

Cell Line, Tumor↗

HIV type 1 A/J recombinant with a pronounced pol gene mosaicism.

A nearly full-length genome sequence of a novel HIV-1 A/J recombinant with a complex structure of the pol gene has been analyzed. This virus was isolated in 1998 from a 35-year-old female from Botswana. The virus demonstrated a dual pattern for CXCR4/CCR5 coreceptor utilization. Using short-term enrichment of the donor's PBMCs, the 98BW21 isolate was long-range amplified, cloned, and sequenced. The sequence of the clone 98BW21.17 spanned 9103 bp from the PBS site to the U5 region of the 3' LTR. The phylogenetic relationship of the 98BW21.17 clone to HIV-1 sequences represented by M, N, and O groups and A-K subtypes of the M group was examined across the entire viral genome. The 98BW21.17 clone demonstrated a unique phylogenetic topology clustering within subtype A or subtype J reference sequences. However, the subtype origin of two regions within the pol gene (p51 RT and integrase) could not be identified. Recombination patterns of the 98BW21.17 clone were different from known AGJ/AGIJ-type viruses such as isolates BFP90 and 95ML84. This study demonstrated the existence and replication competence of a new dual-tropic X4/R5 recombinant form of HIV-1 on the subtype J backbone. The nucleotide sequence of the 98BW21.17 clone was submitted to GenBank under accession number AF192135.

Adult↗

Distinct human immunodeficiency virus type 1 subtype A virus circulating in West Africa: sub-subtype A3.

Phylogenetic analyses demonstrate significant diversity in worldwide circulating strains of human immunodeficiency virus type 1 (HIV-1). Detailed studies have revealed a complex pattern of intersubtype recombinations, as well as evidence of sub-subtypes circulating in various populations. In this study, we characterized an HIV-1 strain that had previously been identified as a distinct subcluster within the subtype A radiation based on partial sequence data. These viruses were of particular interest given that we recently found that their prevalence was significantly higher in dually infected individuals compared to women who were singly infected with HIV-1. Five viruses isolated from commercial sex workers in Dakar, Senegal, were full-length PCR amplified and sequenced. Phylogenetic analyses indicated that, whereas three of these viruses were closely related and clustered overall within the HIV-1 subtype A radiation, they were distinct from previously characterized sub-subtype A1 and A2 viruses. The clustering pattern was maintained in the individual gag, pol, and env regions of the genome. Distance calculations between these viruses, which we termed A3, and other reference sub-subtype A1 and A2 viruses fell in the range of distances between previously characterized sub-subtype groups. In addition, we found evidence of two A3-containing recombinants in our cohort. These recombinants are mosaics composed of sequence from both sub-subtype A3 and CRF02_AG, the major circulating recombinant form in this West African population. Based on phylogenetic analyses, we propose that the group of viruses found in the Dakar sex worker cohort, previously referred to as HIV-1 A subcluster 2, be referred to as HIV-1 sub-subtype A3.

Africa, Western↗

Melatonin receptor RNA is expressed in photoreceptors and displays a diurnal rhythm in Xenopus retina.

Melatonin is an output signal of an endogenous circadian clock of retinal photoreceptors, with highest levels occurring at night. Melatonin synthesized in the retina appears to act as a paracrine signal by binding to specific receptors in the eye. We have previously demonstrated that RNA encoding the Mel(1b) and Mel(1c) melatonin receptor subtypes is expressed in the Xenopus laevis retina. The goal of this study was to determine the distribution of the Mel(1b) and Mel(1c) receptor subtype RNA expression in the retina, and to determine if the level of expression of these receptors exhibits a diurnal rhythm. Sections of frog neural retina were analyzed by in situ hybridization with 35S-labeled Xenopus Mel(1c) and Mel(1b) riboprobes. Hybridization was present in cells of the inner nuclear layer and the ganglion cell layer. Moreover, there was hybridization in the photoreceptors, which has not been previously reported. To test the hypothesis that retinal melatonin receptor mRNA undergoes a diurnal rhythm of expression, total RNA was isolated from frog neural retinas obtained at 3-h intervals during a 24-h period. The total RNA was used in real-time PCR assays to quantify the differences in Mel(1b) and Mel(1c) receptor mRNA expression at various circadian times. Both the Mel(1b) and Mel(1c) receptor RNA demonstrated a diurnal rhythm of expression, with peak levels occurring late in the light period, and lowest levels late in the dark period. These results support the hypothesis that RNA encoding melatonin receptors undergo a diurnal rhythm of expression. To further investigate the possible expression of the Mel(1a) receptor subtype in Xenopus retina, we generated Mel(1a) PCR products in genomic DNA, and in reverse-transcribed neural retina and retinal pigment epithelium (RPE) RNA. The identity of the PCR product was confirmed by sequencing. Therefore, all three known Xenopus melatonin receptor subtypes appear to be expressed in the neural retina and RPE.

Animals↗

Subtype 2c of hepatitis C virus is highly prevalent in Italy and is heterogeneous in the NS5A region.

Hepatitis C virus (HCV) isolates, obtained from 50 Italian patients with community-acquired infection, that had previously been classified as subtype 2a or 2b by current rapid genotyping methods were further characterized by partial sequence analysis. All the isolates were reclassified: 45 within subtype 2c and the other 5 as subtype 1b, 3a, or 4d. Thus, subtype 2c is much more prevalent than previously recognized, with about 30% of all HCV strains detected in Italy being subtype 2c. In contrast, isolates of subtypes 2a and 2b appear to be infrequent, if not absent. Further studies showed that subtype 2c isolates are heterogeneous in the NS5A region, in that they may or may not contain a 57-nucleotide (nt) segment spanning from nt 7533 to nt 7589 of the viral genome. Partial nucleotide sequencing of the NS5B region of four 2c subtypes excluded the possibility that the isolates possessing or not possessing the 57-nt segment in the NS5A region may have resulted from recombination phenomena.

Adult↗

Genotyping of GB virus C by restriction pattern analysis of the 5' untranslated region.

GB virus C (GBV-C) is a virus that has been proposed as a member of the Flaviviridae family, distantly related to hepatitis C virus (HCV). The virus is able to infect humans parenterally and perinatally, although its true pathogenicity remains unknown. The 5' terminal region of GBV-C is the most highly conserved region of the virus genome. Comparison of 5' untranslated region (5' UTR) sequences from GBV-C infected individuals shows that variation is limited to particular sites that are often covariant and associated with different virus genotypes. Extensive sequence analysis of the GBV-C genome provides evidence for the existence of at least five major genotypes, some of which can be further divided into subtypes. For genotyping by restriction fragment length polymorphism (RFLP), it is essential to identify genomic positions that not only reflect genotype differences, but that also harbor restriction sites that allow recognition of these differences. Restriction site analysis of type-specific sequence motifs predicted that endonucleases BsmFI, HaeII, HinfI, and ScrFI could be used for the identification all known genotypes (types 1-5) with 99.6% accuracy. The method was applied to serum samples from 46 chronic GBV-C carriers of heterogeneous geographical and ethnic origin, comparing observed cleavage patterns of GBV-C variants amplified by reverse transcriptase-polymerase chain reaction (RT-PCR) of the 5' UTR with the RFLP predicted from sequences deposited in GenBank database. cDNA sequencing and subsequent alignment of the 46 GBV-C isolates confirmed RFLP profiles predicted theoretically. The observed geographical distribution of genotypes is also in agreement with previous reports. This method may be useful for rapid and reliable characterization of GBV-C isolates when either epidemiological or transmission studies are carried out.

5' Untranslated Regions↗

Different DNA ploidy patterns for the differentiation of common subtypes of renal tumors.

OBJECTIVES: The common subtypes of renal tumors are conventional or clear cell carcinoma, papillary carcinoma, chromophobe carcinoma and oncocytoma. Each subtype has its distinct histogenesis and clinical evolution. DNA ploidy is viewed as a marker of gross genomic aberrations. The aim of this study is to evaluate the DNA ploidy in the common subtypes of renal tumors to increase our understanding of renal tumor biology and to broaden clinical application of DNA ploidy. METHODS: 38 renal tumor samples (13 clear cell RCCs, 12 papillary RCCs, 7 chromophobe RCCs, and 6 oncocytomas) were studied. Five biopsies of different parts of each fresh tumor were subjected to a flow cytometric analysis of DNA ploidy. RESULTS: All tumors except one papillary RCC generated interpretable DNA histograms. Flow cytometric analysis of oncocytomas showed the diploid pattern (29/30 frequencies) while the chromophobe RCC never showed the diploid pattern (0/55 frequencies) (p<0.01). 3/7 chromopbobe RCCs possessed the hypodiploid stemline. The hypodiploid stemline appeared neither in conventional RCCs (0/63 frequencies) nor in papillary RCCs (0/50 frequencies). The diploid pattern was dominant in conventional and papillary RCCs. 10/13 (76.9%) of clear cell RCCs and 9/11 (81.8%) of papillary RCCs possessed a homogeneous DNA ploidy pattern while only 1/7 (14.3%) has a homogeneous DNA ploidy pattern. 6/7 chromophobe RCCs had multiple aneuploid stemlines. CONCLUSIONS: Flow cytometric analysis reveals that conventional and papillary RCCs are more homogeneous than chromophobe RCC. Each subtype of renal tumors possesses a specific DNA ploidy pattern. The analysis of DNA ploidy is useful for the differentiation of common subtypes of renal tumors in morphologically difficult cases.

Adenocarcinoma, Clear Cell↗