Discordant results for ALK based on immunohistochemistry versus fluorescence in situ hybridization in a cohort of patients diagnosed with lung adenocarcinoma / Discordancia de los resultados para ALK basados en inmunohistoquímica e hibridación fluorescente in situ en una cohorte de pacientes diagnosticados con adenocarcinoma de pulmón

Introduction: Anaplastic lymphoma kinase (ALK) rearrangement located on the short arm of chromosome 2, region 2 and band 3 is frequent in lung cancer patients who respond to targeted therapies with ALK inhibitors Therefore, their identification has become a standard diagnostic test in patients with advanced NSCLS, as such chromosomal alterations may lead to the activation of important signalling pathways involved in cell survival and proliferation. Methods: To investigate the ALK gene status, we performed FISH and IHC assays in 18 lung adenocarcinoma patients, 12 women and 6 men, aged between 29 and 85 years. Paraffin-embedded samples were analyzed in the Pathology Department of the Hospital Universitario San Ignacio. Results: Results between the two techniques in 5 patients showed discordant patterns, being positive for FISH and negative for IHC. The borderline to define ALK positivity was set at 15%, These results present experimental evidence that the techniques differ in specific situations. Conclusions: Our findings show that it is advisable to investigate the ALK gene status in patients with suspected lung cancer using both FISH and IHC in combination.(AU)

Introducción: La reorganización de la (anaplastic lymphoma kinase) ALK ubicada en el brazo corto del cromosoma 2, región 2 y banda 3 es frecuente en los pacientes con cáncer de pulmón que responden a terapias dirigidas con inhibidores de la ALK. Por ello, su identificación se ha establecido como una prueba diagnóstica estándar en pacientes con CPCNP, ya que dichas alteraciones cromosómicas puedan determinar la activación de importantes vías de señalización implicadas en la supervivencia y proliferación celulares. Métodos: Para determinar el estatus de gen ALK se realizaron pruebas FISH e IHC en 18 pacientes con adenocarcinoma pulmonar, 12 mujeres y 6 varones, con edades comprendidas entre 29 y 85 años. Las muestras fueron analizadas en el Departamento de Anatomía Patológica del Hospital Universitario San Ignacio. Resultados: Los resultados entre ambas técnicas mostraron patrones discordantes en 5 pacientes, con positividad de FISH y negatividad con IHC. El límite para definir la positividad de ALK se estableció en el 15%. Estos resultados muestran evidencia experimental que dichas técnicas difieren en situaciones específicas. Conclusiones: Este estudio recomienda la investigación del estatus del gen ALK en los pacientes con sospecha de cáncer de pulmón, mediante la combinación de FISH e IHC.(AU)

Discordant results for ALK based on immunohistochemistry versus fluorescence in situ hybridization in a cohort of patients diagnosed with lung adenocarcinoma.

INTRODUCTION: Anaplastic lymphoma kinase (ALK) rearrangement located on the short arm of chromosome 2, region 2 and band 3 is frequent in lung cancer patients who respond to targeted therapies with ALK inhibitors Therefore, their identification has become a standard diagnostic test in patients with advanced NSCLS, as such chromosomal alterations may lead to the activation of important signalling pathways involved in cell survival and proliferation. METHODS: To investigate the ALK gene status, we performed FISH and IHC assays in 18 lung adenocarcinoma patients, 12 women and 6 men, aged between 29 and 85 years. Paraffin-embedded samples were analyzed in the Pathology Department of the Hospital Universitario San Ignacio. RESULTS: Results between the two techniques in 5 patients showed discordant patterns, being positive for FISH and negative for IHC. The borderline to define ALK positivity was set at 15%, These results present experimental evidence that the techniques differ in specific situations. CONCLUSIONS: Our findings show that it is advisable to investigate the ALK gene status in patients with suspected lung cancer using both FISH and IHC in combination.

Identification of common differentially expressed genes in Turner (45,X) and Klinefelter (47,XXY) syndromes using bioinformatics analysis.

BACKGROUND: Analysis of patients with chromosomal abnormalities, including Turner syndrome and Klinefelter syndrome, has highlighted the importance of X-linked gene dosage as a contributing factor for disease susceptibility. Escape from X-inactivation and X-linked imprinting can result in transcriptional differences between normal men and women as well as in patients with sex chromosome abnormalities. OBJECTIVE: To identify differentially expressed genes among patients with Turner (45,X) and Klinefelter (46,XXY) syndrome using bioinformatics analysis. METHODOLOGY: Two gene expression data sets of Turner (45,X) and Klinefelter syndrome (47,XXY) were obtained from the Gene Omnibus Expression (GEO) database of the National Center for Biotechnology Information (NCBI). Statistical analysis was performed using R Bioconductor libraries. Differentially expressed genes (DEGs) were determined using significance analysis of microarray (SAM). The functional annotation of the DEGs was performed with DAVID v6.8 (The Database for Annotation, Visualization, and Integrated Discovery). RESULTS: There are no genes over-expressed simultaneously in both diseases. However, when crossing the list of under-expressed genes for 45,X cells and the list of over-expressed genes for 47,XXY cells, there are 16 common genes: SLC25A6, AKAP17A, ASMTL, KDM5C, KDM6A, ATRX, CSF2RA, DHRSX, CD99, ZBED1, EIF1AX, MVB12B, SMC1A, P2RY8, DOCK7, DDX3X, eight of which are involved in the regulation of gene expression by epigenetic mechanisms, regulation of splicing processes and protein synthesis. CONCLUSION: Of the 16 identified as under-expressed in 45,X cells and over-expressed in 47,XXY cells, 14 are located in X chromosome and 2 in autosomal chromosome; 8 of these genes are involved in the regulation of gene expression: 5 genes are related to epigenetic mechanisms, 2 in regulation of splicing processes, and 1 in the protein synthesis process. Our results are limited by it being the product of a bioinformatic analysis from mRNA isolated from whole blood, this makes necessary further exploration of the relationships between these genes and Turner syndrome and Klinefelter syndrome in the future.

Clinical and Molecular Cytogenetic Characteristics of Five Cases with Isodicentric Y Chromosome.

Isodicentric Y chromosome [idic(Y)] is one of the most common structural abnormalities of the Y chromosome and has been observed in patients with reproductive disorders and in patients with disorders of sexual development. Most idic(Y) chromosomes are found in mosaic form with a 45,X cell line. These chromosomes are highly unstable during mitosis due to the presence of 2 centromers, which explains their probable loss in early mitosis or mitosis of the embryo and therefore the presence of the 45,X line. It has been hypothesized that the proportion of 45,X cells in various tissues probably influences the phenotypic sex of individuals carrying an idic(Y) chromosome, ranging from infertile men, hypospadias, ambiguous genitalia, and Turner syndrome to sex reversal. In this article we present 5 cases of patients with idic(Y) referred for suspected disorder of sex development (DSD), 3 with a male assignment and 2 with a female assignment. All cases have variable clinical characteristics, which were assessed by the transdisciplinary group of Disorders of Sex Development of the Hospital Universitario San Ignacio, Bogotá, Colombia. Patients were analyzed by conventional and molecular cytogenetics using high-resolution G-band and FISH techniques. Our findings highlight the importance of cytogenetic studies in the diagnosis of DSD patients.

Phenotypic Characteristics and Copy Number Variants in a Cohort of Colombian Patients with VACTERL Association.

VACTERL association (OMIM 192350) is a heterogeneous clinical condition characterized by congenital structural defects that include at least 3 of the following features: vertebral abnormalities, anal atresia, heart defects, tracheoesophageal fistula, renal malformations, and limb defects. The nonrandom occurrence of these malformations and some familial cases suggest a possible association with genetic factors such as chromosomal alterations, gene mutations, and inherited syndromes such as Fanconi anemia (FA). In this study, the clinical phenotype and its relationship with the presence of chromosomal abnormalities and FA were evaluated in 18 patients with VACTERL association. For this, a G-banded karyotype, array-comparative genomic hybridization, and chromosomal fragility test for FA were performed. All patients (10 female and 8 male) showed a broad clinical spectrum: 13 (72.2%) had vertebral abnormalities, 8 (44.4%) had anal atresia, 14 (77.8%) had heart defects, 8 (44.4%) had esophageal atresia, 10 (55.6%) had renal abnormalities, and 10 (55.6%) had limb defects. Chromosomal abnormalities and FA were ruled out. In 2 cases, the finding of microalterations, namely del(15)(q11.2) and dup(17)(q12), explained the phenotype; in 8 cases, copy number variations were classified as variants of unknown significance and as not yet described in VACTERL. These variants comprise genes related to important cellular functions and embryonic development.