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1.
J. coloproctol. (Rio J., Impr.) ; 40(4): 404-411, Oct.-Dec. 2020.
Article in English | LILACS | ID: biblio-1143186

ABSTRACT

ABSTRACT Introduction: Colorectal cancer is one of the neoplasms with the greatest social impact. Given the great molecular heterogeneity and diversity of pathophysiological mechanisms, it is difficult to define prognostic factors that could guide therapy. Objectives: To identify the molecular prognostic factors that may be of interest in clinical practice and to synthesize the existing evidence. Material and methods: The search for the articles was carried out using the PubMed platform and the keywords "sporadic colorectal cancer and prognosis", for articles published between 2014 and 2019. We selected all articles published on studies in humans and written in English or Portuguese. Of the 215 articles found, 35 articles were selected to perform this review. Results: Current evidence supports the use of four molecular markers in clinical practice − KRAS, NRAS and BRAF (EGFR signalling pathway) and the mismatch repair status. Conclusion: The use of molecular biomarkers in clinical practice to define prognosis is still little supported by the existent evidence. The studies are slightly contradictory, so new projects and international collaborations must be carried out in this area to obtain more robust evidence.


RESUMO Introdução: O carcinoma colorretal é uma das neoplasias com maior impacto social. Dada a grande heterogeneidade molecular e diversidade de mecanismos fisiopatológicos, torna-se difícil definir fatores de prognóstico que orientem a terapêutica. Objetivos: Identificar os fatores de prognóstico moleculares que poderão vir a ter interesse na prática clínica e fazer uma síntese da evidência existente. Material e métodos: A pesquisa dos artigos foi realizada recorrendo à plataforma PubMed e utilizou-se as palavras-chave "sporadic colorectal cancer and prognosis", para artigos publicados entre 2014 e 2019. Foram selecionados todos os artigos publicados sobre estudos em humanos e escritos em inglês ou em português. Dos 215 artigos encontrados, foram selecionados 35 artigos para realizar esta revisão. Resultados: A evidência atual apoia a utilização de quatro marcadores moleculares na prática clínica - KRAS, NRAS e BRAF (via de sinalização do EGFR) e o estado mismatch repair. Conclusão: A utilização na prática clínica de biomarcadores moleculares para definir o prognóstico é ainda pouco apoiada pela evidência disponível. Os estudos são algo contraditórios, pelo que novos projetos e colaborações internacionais devem ser realizados neste âmbito para se obter evidência mais robusta.


Subject(s)
Humans , Carcinoma , Biomarkers , Colorectal Neoplasms/diagnosis , Chromosomal Instability , Microsatellite Instability , Prognosis
2.
Clinical Endoscopy ; : 235-238, 2019.
Article in English | WPRIM | ID: wpr-763437

ABSTRACT

Conventional adenomas have historically been considered to be the only screening-relevant colorectal cancer (CRC) precursor lesion. The prevailing paradigm was that most CRCs arise along the chromosomal instability pathway, where adenomas accumulate incremental genetic alterations over time, leading eventually to malignancy. However, it is now recognized that this “conventional” pathway accounts for only about two-thirds of CRCs. The serrated pathway is responsible for most of the remainder, and is a disproportionate contributor to postcolonoscopy CRC. Hallmarks of the serrated pathway are mutations in the BRAF gene, high levels of methylation of promoter CpG islands, and the sessile serrated polyp (SSP). Accumulating evidence shows that SSPs can be considered adenoma-equivalent from the standpoint of CRC screening. SSPs have a higher prevalence than previously thought, and appear to have a relatively long dwell time similar to that of conventional adenomas. In addition, SSPs, whether sporadic or as part of the serrated polyposis syndrome, are associated with increased risk of synchronous and metachronous neoplasia. These features collectively support that SSPs are highly relevant to CRC prevention.


Subject(s)
Adenoma , Chromosomal Instability , Colonoscopy , Colorectal Neoplasms , CpG Islands , Mass Screening , Methylation , Polyps , Prevalence
3.
Annals of Coloproctology ; : 280-285, 2018.
Article in English | WPRIM | ID: wpr-718754

ABSTRACT

For many years, developmental and physiological differences have been known to exist between anatomic segments of the colorectum. Because of different outcomes, prognoses, and clinical responses to chemotherapy, the distinction between right colon cancer (RCC) and left colon cancer (LCC) has gained attention. Furthermore, variations in the molecular features and gut microbiota between right and LCCs have recently been a hot research topic. CpG island methylator phenotype-high, microsatellite instability-high colorectal cancers are more likely to occur on the right side whereas tumors with chromosomal instability have been detected in approximately 75% of LCC patients and 30% of RCC patients. The mutation rates of oncogenes and tumor suppressor genes also differ between RCC and LCC patients. Biofilm is more abundant in RCC patients than LLC patients, as are Prevotella, Selenomonas, and Peptostreptococcus. Conversely, Fusobacterium, Escherichia/Shigella, and Leptotrichia are more abundant in LCC patients compared to RCC patients. Distinctive characteristics are apparent in terms of molecular features and gut microbiota between right and LCC. However, how or to what extent these differences influence diverging oncologic outcomes remains unclear. Further clinical and translational studies are needed to elucidate the causative relationship between primary tumor location and prognosis.


Subject(s)
Biofilms , Chromosomal Instability , Colon , Colonic Neoplasms , Colorectal Neoplasms , CpG Islands , Drug Therapy , Fusobacterium , Gastrointestinal Microbiome , Genes, Tumor Suppressor , Humans , Leptotrichia , Microsatellite Repeats , Mutation Rate , Oncogenes , Peptostreptococcus , Prevotella , Prognosis , Selenomonas , Treatment Outcome
4.
Article in English | WPRIM | ID: wpr-713805

ABSTRACT

Urine-derived stem cells (USCs) are considered as a promising cell source capable of neuronal differentiation. In addition, specific growth factors and extracellular matrix are essential for enhancing their neuronal differentiation efficiency. In this study, we investigated the possibility of neuronal differentiation of USCs and the role of laminin and platelet-derived growth factor BB (PDGF-BB) as promoting factors. USCs were isolated from fresh urine of healthy donors. Cultured USCs were adherent to the plate and their morphology was similar to the cobblestone. In addition, they showed chromosome stability, rapid proliferation rate, colony forming capacity, and mesenchymal stem cell characteristics. For inducing the neuronal differentiation, USCs were cultured for 14 days in neuronal differentiation media supplemented with/without laminin and/or PDGF-BB. To identify the expression of neuronal markers, RT-PCR, flow cytometry analysis and immunocytochemistry were used. After neuronal induction, the cells showed neuron-like morphological change and high expression level of neuronal markers. In addition, laminin and PDGF-BB respectively promoted the neuronal differentiation of USCs and the combination of laminin and PDGF-BB showed a synergistic effect for the neuronal differentiation of USCs. In conclusion, USCs are noteworthy cell source in the field of neuronal regeneration and laminin and PDGF-BB promote their neuronal differentiation efficiency.


Subject(s)
Chromosomal Instability , Extracellular Matrix , Flow Cytometry , Humans , Immunohistochemistry , Intercellular Signaling Peptides and Proteins , Laminin , Mesenchymal Stem Cells , Neurons , Platelet-Derived Growth Factor , Regeneration , Stem Cells , Tissue Donors
5.
Appl. cancer res ; 37: 1-13, 2017. ilus
Article in English | LILACS, Inca | ID: biblio-915440

ABSTRACT

Molecular pathology is playing an increasingly important role in the treatment and overall management of patients with colorectal carcinoma. Three distinct genetic pathways have been identified that play a role in carcinogenesis: the chromosomal instability pathway, the microsatellite instability pathway, and the CpG island methylator phenotype pathway. Certain genetic mutations, some of which overlap with the aforementioned pathways, can also indicate that a carcinoma patient has a genetic predisposition syndrome, such as familial adenomatous polyposis, Lynch syndrome, and hamartomatous polyposis syndromes. A variety of advanced methods, including next-generation sequencing, are available to test for these and other mutations, such as targetable mutations that may allow tailoring of a treatment regimen to a patient's specific cancer (e.g., KRAS and BRAF mutations). The possible future role of testing circulating tumor cells is also addressed. New mutations and syndromes continue to be discovered, ensuring that our knowledge of colorectal carcinoma and our ability to treat it will advance in the future (AU)


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Aged, 80 and over , Neoplastic Syndromes, Hereditary , Colorectal Neoplasms/genetics , Chromosomal Instability , Pathology, Molecular , Carcinogenesis
6.
Article in English | WPRIM | ID: wpr-13606

ABSTRACT

BACKGROUND: Aurora kinase A (AURKA), or STK15/BTAK, is a member of the serine/threonine kinase family and plays important roles in mitosis and chromosome stability. This study investigated the clinical significance of AURKA expression in colorectal cancer patients in Korea. METHODS: AURKA protein expression was evaluated by immunohistochemistry in 151 patients with colorectal adenocarcinoma using tissue microarray blocks. We analyzed the relationship between clinicopathological characteristics and AURKA expression. In addition, the prognostic significance of various clinicopathological data for progression-free survival (PFS) was assessed. Also we evaluated copy number variations by array comparative genomic hybridization and AURKA gene amplification using fluorescence in situ hybridization in colorectal carcinoma tissues. RESULTS: AURKA gene amplification was found more frequently in the 20q13.2–13.33 gain-positive group than the group with no significant gain on the AURKA-containing locus. AURKA protein expression was detected in 45% of the cases (68/151). Positive staining for AURKA was observed more often in male patients (p = .035) and distally located tumors (p = .021). PFS was shorter in patients with AURKA expression compared to those with low-level AURKA expression (p < .001). Univariate analysis revealed that AURKA expression (p = .001), age (p = .034), lymphatic invasion (p = .001), perineural invasion (p = .002), and TNM stage (p = .013) significantly affected PFS. In a multivariate analysis of PFS, a Cox proportional hazard model confirmed that AURKA expression was an independent and significant prognostic factor in colorectal adenocarcinoma (hazard ratio, 3.944; p < .001). CONCLUSIONS: AURKA could serve as an independent factor to predict a poor prognosis in Korean colorectal adenocarcinoma patients.


Subject(s)
Adenocarcinoma , Aurora Kinase A , Chromosomal Instability , Colorectal Neoplasms , Comparative Genomic Hybridization , Disease-Free Survival , Fluorescence , Gene Amplification , Humans , Immunohistochemistry , In Situ Hybridization , Korea , Male , Mitosis , Multivariate Analysis , Phosphotransferases , Prognosis , Proportional Hazards Models
7.
Article in English | WPRIM | ID: wpr-225237

ABSTRACT

Gastric cancer is a global health burden and has the highest incidence in East Asia. This disease is complex in nature because it arises from multiple interactions of genetic, local environmental, and host factors, resulting in biological heterogeneity. This genetic intricacy converges on molecular characteristics reflecting the pathophysiology, tumor biology, and clinical outcome. Therefore, understanding the molecular characteristics at a genomic level is pivotal to improving the clinical care of patients with gastric cancer. A recent landmark study, The Cancer Genome Atlas (TCGA) project, showed the molecular landscape of gastric cancer through a comprehensive molecular evaluation of 295 primary gastric cancers. The proposed molecular classification divided gastric cancer into four subtypes: Epstein-Barr virus-positive, microsatellite unstable, genomic stable, and chromosomal instability. This information will be taken into account in future clinical trials and will be translated into clinical therapeutic decisions. To fully realize the clinical benefit, many challenges must be overcome. Rapid growth of high-throughput biology and functional validation of molecular targets will further deepen our knowledge of molecular dimensions of this cancer, allowing for personalized precision medicine.


Subject(s)
Biology , Chromosomal Instability , Classification , Far East , Genome , Humans , Incidence , Microsatellite Repeats , Population Characteristics , Stomach Neoplasms , Translational Medical Research
8.
Article in Chinese | WPRIM | ID: wpr-345406

ABSTRACT

As an important telomere binding protein, TPP1 protects the ends of telomeres and maintains the stability and integrity of its structure and function by interacting with other five essential core proteins (POT1, TRF1, TRF2, TIN2, and RAP1) to form a complex called Shelterin. Recently, researchers have discovered that TPP1 participates in protection of telomeres and regulation of telomerase activity. The relationship between TPP1 and tumorigenesis, tumor progression and treatment has also been investigated. This paper reviews the latest findings of TPP1 regarding to its structure, function and interaction with other proteins involved in tumorigenesis.


Subject(s)
Chromosomal Instability , DNA Damage , Humans , Neoplasms , Genetics , Telomere , Telomere-Binding Proteins , Chemistry , Physiology
9.
Article in English | WPRIM | ID: wpr-651456

ABSTRACT

Upper urinary tract-derived urine stem cells (USCs) are considered a valuable mesenchymal stem cell source for autologous cell therapy. However, the reported culture condition for USCs is not appropriate for large-quantity production, because cells can show limited replicativity, senescence, and undesirable differentiation during cultivation. These drawbacks led us to reconstitute a culture condition that mimics the natural stem cell niche. We selected extracellular matrix protein and oxygen tension to optimize the ex vivo expansion of USCs, and compared cell adhesion, proliferation, gene expression, chromosomal stability, differentiation capacity, immunity and safety. Culture on collagen type I (ColI) supported highly enhanced USC proliferation and retention of stem cell properties. In the oxygen tension analysis (with ColI), 5% O₂ hypoxia showed a higher cell proliferation rate, a greater proportion of cells in the S phase of the cell cycle, and normal stem cell properties compared to those observed in cells cultured under 20% O₂ normoxia. The established reconstituted condition (ColI/hypoxia, USCs(recon)) was compared to the control condition. The expanded USCs(recon) showed highly increased cell proliferation and colony forming ability, maintained transcription factors, chromosomal stability, and multi-lineage differentiation capacity (neuron, osteoblast, and adipocyte) compared to the control. In addition, USCs(recon) retained their immune-privileged potential and non-tumorigenicity with in vivo testing at week 8. Therefore, reconstituted condition allows for expanded uUSC cell preparations that are safe and useful for application in stem cell therapy.


Subject(s)
Aging , Hypoxia , Cell Adhesion , Cell Cycle , Cell Proliferation , Cell- and Tissue-Based Therapy , Chromosomal Instability , Collagen Type I , Extracellular Matrix , Gene Expression , Mesenchymal Stem Cells , Osteoblasts , Oxygen , S Phase , Stem Cell Niche , Stem Cells , Transcription Factors
10.
Chinese Journal of Hematology ; (12): 770-774, 2015.
Article in Chinese | WPRIM | ID: wpr-296155

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the genetic instability in patients with Dyskeration congenita.</p><p><b>METHODS</b>The spontaneous chromosome instability of lymphocytes from 4 DC patients, 29 FA patients and 24 healthy volunteers was assessed with comet assay. The percent of DNA in comet head (HeadDNA%), the percent of DNA in comet tail (TailDNA%), tail moment (TM), olive tail moment (OTM), the comet cell percentage (CCP) were compared between groups. And the results of MMC test, PNH clones and karotype were analysed additionally. The correlation between TM, OTM, CCP and the severity degree of bone marrow failure in DC group were evaluated.</p><p><b>RESULTS</b>①PNH clones and karotype abnormalities were not found in 4 DC patients. ②TM (6.77 ± 0.90), OTM(6.19 ± 0.80) and CCP [(46.00 ± 5.03) %] in DC were significantly higher than those in normal control group [0.61 ± 0.49, 0.66 ± 0.42, (5.91 ± 3.19)%, P<0.05], however, not distinguished from FA patients [7.81 ± 3.58, 6.65 ± 2.21, (56.03 ± 13.47) %, P ≥ 0.05]. The aberrant cell percent at the MMC concentration of 80 μg/L in DC group was significantly lower than that in FA group [(21.00 ± 3.16) % vs (31.97 ± 6.33)%, P=0.003]. ③The correlation between TM, OTM, CCP and the severity of bone marrow failure in DC group were not found (P>0.05).</p><p><b>CONCLUSION</b>DC patients were of significantly increased genetic instability and normal DNA repair, which was different from that in FA patients. And there was no correlation between the degree of genetic instability and the severity of bone marrow failure in DC patients presenting as aplastic anemia.</p>


Subject(s)
Case-Control Studies , Chromosomal Instability , Comet Assay , Dyskeratosis Congenita , Genetics , Fanconi Anemia , Genetics , Humans , Lymphocytes , Pancytopenia
11.
Article in English | WPRIM | ID: wpr-164159

ABSTRACT

Adipose tissue stem cells (ADSCs) would be an attractive autologous cell source. However, ADSCs require invasive procedures, and has potential complications. Recently, urine stem cells (USCs) have been proposed as an alternative stem cell source. In this study, we compared USCs and ADSCs collected from the same patients on stem cell characteristics and capacity to differentiate into various cell lineages to provide a useful guideline for selecting the appropriate type of cell source for use in clinical application. The urine samples were collected via urethral catheterization, and adipose tissue was obtained from subcutaneous fat tissue during elective laparoscopic kidney surgery from the same patient (n = 10). Both cells were plated for primary culture. Cell proliferation, colony formation, cell surface markers, immune modulation, chromosome stability and multi-lineage differentiation were analyzed for each USCs and ADSCs at cell passage 3, 5, and 7. USCs showed high cell proliferation rate, enhanced colony forming ability, strong positive for stem cell markers expression, high efficiency for inhibition of immune cell activation compared to ADSCs at cell passage 3, 5, and 7. In chromosome stability analysis, both cells showed normal karyotype through all passages. In analysis of multi-lineage capability, USCs showed higher myogenic, neurogenic, and endogenic differentiation rate, and lower osteogenic, adipogenic, and chondrogenic differentiation rate compared to ADSCs. Therefore, we expect that USC can be an alternative autologous stem cell source for muscle, neuron and endothelial tissue reconstruction instead of ADSCs.


Subject(s)
Adult Stem Cells/cytology , Biomarkers/metabolism , Cell Differentiation , Cell Lineage , Cell Proliferation , Cell Separation , Chromosomal Instability , Colony-Forming Units Assay , Humans , Karyotyping , Multipotent Stem Cells/cytology , Subcutaneous Fat, Abdominal/cytology , Transplantation, Autologous , Urine/cytology
12.
Rev. med. Rosario ; 80(2): 63-74, mayo-ago. 2014. ilus
Article in Spanish | LILACS | ID: lil-725905

ABSTRACT

El cáncer colorrectal (CCR) es una de las principales causas de morbilidad y mortalidad a nivel mundial. Clásicamente se considera a los adenomas como las lesiones precursoras del CCR y se estipula un tiempo de 10 a 15 años para completar la secuencia adenoma-carcinoma. El CCR evoluciona a través de la acumulación progresiva de alteraciones genéticas y epigenéticas, las que conducen a la transformación de la mucosa colónica normal en cáncer invasivo. La identificación de diferentes vías moleculares de carcinogénesis colorrectal ha demostrado la naturaleza heterogénea del cáncer colónico. De reciente descripción, las lesiones aserradas muestran cambios moleculares y patológicos distintos a los adenomas tradicionales, estimándose que presentan un tiempo más acelerado de evolución hacia la malignidad. El objetivo de esta revisión es actualizar conocimientos sobre la génesis tumoral y sus bases biomoleculares a fin de posibilitar su aplicación a etapas clínicas concretas como la prevención y el tratamiento


Colorectal cancer (CRC) is one of the main causes of morbidity and mortality worldwide. Adenomas are classically regarded as precursor lesions of CRC and between 10 and 15 years is thought to elapse to complete the adenoma-carcinoma sequence. CRC evolves through the progressive accumulation of genetic and epigenetic alterations that lead to invasive cancer through the transformation of normal colonic mucosa. The identification of different molecular pathways of colorectal carcinogenesis has demonstrated the heterogeneous nature of colon cancer. Recent description of serrated lesions shows molecular and pathological changes other than traditional adenomas with an estimated faster time of progression to malignancy. The aim of this review is to update the knowledge about tumorigenesis and its biomolecular basis for clinical application in early stages providing firm ground for prevention and treatment


Subject(s)
Humans , Adult , Colonoscopy , Disease Prevention , Epigenesis, Genetic/genetics , Genes, Neoplasm/genetics , Precancerous Conditions/pathology , Colorectal Neoplasms/pathology , DNA Methylation , Determination/prevention & control , Heredity/genetics , Chromosomal Instability/genetics , Microsatellite Instability , Mucous Membrane/abnormalities , Phenotype , Review Literature as Topic
13.
Rev. bras. hematol. hemoter ; 36(3): 202-207, May-Jun/2014. tab, graf
Article in English | LILACS | ID: lil-713677

ABSTRACT

OBJECTIVE: To present the initial results of first three years of implementation of a genetic evaluation test for bone marrow-derived mesenchymal stem cells in a Cell Technology Center. METHODS: A retrospective study was carried out of 21 candidates for cell therapy. After the isolation of bone marrow mononuclear cells by density gradient, mesenchymal stem cells were cultivated and expanded at least until the second passage. Cytogenetic analyses were performed before and after cell expansion (62 samples) using G-banded karyotyping. RESULTS: All the samples analyzed, before and after cell expansion, had normal karyotypes, showing no clonal chromosomal changes. Signs of chromosomal instability were observed in 11 out of 21 patients (52%). From a total of 910 analyzed metaphases, five chromatid gaps, six chromatid breaks and 14 tetraploid cells were detected giving as total of 25 metaphases with chromosome damage (2.75%). CONCLUSION: The absence of clonal chromosomal aberrations in our results for G-banded karyotyping shows the maintenance of chromosomal stability of bone marrow-derived mesenchymal stem cells until the second passage; however, signs of chromosomal instability such as chromatid gaps, chromosome breaks and tetraploidy indicate that the long-term cultivation of these cells can provide an intermediate step for tumorigenesis. .


Subject(s)
Humans , Male , Female , Cytogenetics , Chromosomal Instability , Mesenchymal Stem Cells , Karyotyping
14.
Mem. Inst. Oswaldo Cruz ; 109(1): 15-20, 02/2014. tab
Article in English | LILACS | ID: lil-703643

ABSTRACT

In this study, we analysed the frequency of micronuclei (MN), nucleoplasmic bridges (NPBs) and nuclear buds (NBUDs) and evaluated mutagen-induced sensitivity in the lymphocytes of patients chronically infected with hepatitis B virus (HBV) or hepatitis C virus (HCV). In total, 49 patients with chronic viral hepatitis (28 HBV-infected and 21 HCV-infected patients) and 33 healthy, non-infected blood donor controls were investigated. The frequencies (‰) of MN, NPBs and NBUDs in the controls were 4.41 ± 2.15, 1.15 ± 0.97 and 2.98 ± 1.31, respectively. The frequencies of MN and NPBs were significantly increased (p < 0.0001) in the patient group (7.01 ± 3.23 and 2.76 ± 2.08, respectively) compared with the control group. When considered separately, the HBV-infected patients (7.18 ± 3.57) and HCV-infected patients (3.27 ± 2.40) each had greater numbers of MN than did the controls (p < 0.0001). The HCV-infected patients displayed high numbers of NPBs (2.09 ± 1.33) and NBUDs (4.38 ± 3.28), but only the HBV-infected patients exhibited a significant difference (NPBs = 3.27 ± 2.40, p < 0.0001 and NBUDs = 4.71 ± 2.79, p = 0.03) in comparison with the controls. Similar results were obtained for males, but not for females, when all patients or the HBV-infected group was compared with the controls. The lymphocytes of the infected patients did not exhibit sensitivity to mutagen in comparison with the lymphocytes of the controls (p = 0.06). These results showed that the lymphocytes of patients who were chronically infected with HBV or HCV presented greater chromosomal instability.


Subject(s)
Adult , Female , Humans , Male , Middle Aged , Young Adult , Cell Nucleus/virology , Hepatitis B, Chronic/virology , Hepatitis C, Chronic/virology , Lymphocytes/virology , Micronuclei, Chromosome-Defective/statistics & numerical data , Age Factors , Analysis of Variance , Chi-Square Distribution , Chromosomal Instability , Cell Nucleus/ultrastructure , DNA Damage , Lymphocytes/ultrastructure , Micronucleus Tests , Sex Factors
15.
Biosci. j. (Online) ; 30(1): 245-259, jan./feb. 2014. tab, ilus
Article in English | LILACS | ID: biblio-946998

ABSTRACT

The two conflicting visions of tumorigenesis that are widely discussed are the gene-mutation hypothesis and the aneuploidy hypothesis. In this review we will summarize the contributions of cytogenetics in the study of cancer cells and propose a hypothetical model to explain the influence of cytogenetic events in carcinogenesis, emphasizing the role of aneuploidy. The gene mutation hypothesis states that gene-specific mutations occur and that they maintain the altered phenotype of the tumor cells, and the aneuploidy hypothesis states that aneuploidy is necessary and sufficient for the initiation and progression of malignant transformation. Aneuploidy is a hallmark of cancer and plays an important role in tumorigenesis and tumor progression. Aneuploid cells might be derived from polyploid cells, which can arise spontaneously or are induced by environmental agents or chemical compounds, and the genetic instability observed in polyploid cells leads to chromosomal losses or rearrangements, resulting in variable aberrant karyotypes. Because of the large amount of evidence indicating that the correct chromosomal balance is crucial to cancer development, cytogenetic techniques are important tools for both basic research, such as elucidating carcinogenesis, and applied research, such as diagnosis, prognosis and selection of treatment. The combination of classic cytogenetics, molecular cytogenetics and molecular genetics is essential and can generate a vast amount of data, enhancing our knowledge of cancer biology and improving treatment of this disease.


As duas visões conflitantes da tumorigênese que são amplamente discutidas são a hipótese da mutação gênica e a hipótese da aneuploidia. Nesta revisão vamos resumir as contribuições da citogenética no estudo das células tumorais e propor um modelo hipotético para explicar a influência dos eventos citogenéticos na carcinogênese, enfatizando o papel da aneuploidia. A teoria da mutação gênica estabelece que mutações específicas ocorrem e mantêm o fenótipo alterado das células de um tumor, enquanto a hipótese da aneuploidia estabelece que a aneuploidia é necessária e suficiente para a iniciação e progressão da transformação maligna. A aneuploidia é considerada um marcador do câncer e esta desempenha um importante papel tanto na tumorigênese, quanto na progressão tumoral. Células aneuplóides podem ser derivadas de células poliplóides, que surgem espontaneamente ou são induzidas por agentes ambientais ou compostos químicos. A instabilidade genética observada em células poliplóides leva a perdas ou rearranjos cromossômicos, resultando em cariótipos variavelmente aberrantes. Devido à grande quantidade de evidências indicando que um balanço cromossômico correto é crucial para o desenvolvimento do câncer, as técnicas citogenéticas são ferramentas importantes tanto para a pesquisa básica, tais como pesquisas para elucidar a carcinogênese, quanto pesquisas aplicadas, como no diagnóstico, prognóstico e escolha do tratamento. A combinação da citogenética clássica, citogenética molecular e genética molecular é essencial e pode gerar uma grande quantidade de dados, aumentando o nosso conhecimento da biologia do câncer, melhorando assim o tratamento desta doença.


Subject(s)
Chromosomes , Cytogenetics , Chromosomal Instability , Neoplasms
16.
Mycobiology ; : 46-51, 2014.
Article in English | WPRIM | ID: wpr-730022

ABSTRACT

A degenerated strain of Pleurotus eryngii KNR2312 was isolated from a commercial farm. Random amplified polymorphic DNA analysis performed on the genomic DNA of the normal and degenerated strains of this species revealed differences in the DNA banding pattern. A unique DNA fragment (1.7 kbp), which appeared only in the degenerated strain, was isolated and sequenced. Comparing this sequence with the KNR2312 genomic sequence showed that the sequence of the degenerated strain comprised three DNA regions that originated from nine distinct scaffolds of the genomic sequence, suggesting that chromosome-level changes had occurred in the degenerated strain. Using the unique sequence, three sets of PCR primers were designed that targeted the full length, the 5' half, and the 3' half of the DNA. The primer sets P2-1 and P2-2 yielded 1.76 and 0.97 kbp PCR products, respectively, only in the case of the degenerated strain, whereas P2-3 generated a 0.8 kbp product in both the normal and the degenerated strains because its target region was intact in the normal strain as well. In the case of the P2-1 and P2-2 sets, the priming regions of the forward and reverse primers were located at distinct genomic scaffolds in the normal strain. These two primer sets specifically detected the degenerate strain of KNR2312 isolated from various mushrooms including 10 different strains of P. eryngii, four strains of P. ostreatus, and 11 other wild mushrooms.


Subject(s)
Agaricales , Chromosomal Instability , DNA , Genetic Markers , Pleurotus , Polymerase Chain Reaction
17.
Intestinal Research ; : 184-193, 2014.
Article in English | WPRIM | ID: wpr-123040

ABSTRACT

The extensive study of genetic alterations in colorectal cancer (CRC) has led to molecular diagnostics playing an increasingly important role in CRC diagnosis and treatment. Currently, it is believed that CRC is a consequence of the accumulation of both genetic and epigenetic genomic alterations. It is known that there are at least 3 major pathways that lead to colorectal carcinogenesis: (1) the chromosomal instability pathway, (2) the microsatellite instability pathway, and (3) the cytosine-phospho-guanine island methylator phenotype pathway. With recent advances in CRC genetics, the identification of specific molecular alterations responsible for CRC pathogenesis has directly influences clinical care. Patients at high risk for developing CRC can be identified by genetic testing for specific molecular alterations, and the use of molecular biomarkers for predictive and prognostic purposes is also increasing. This is clearly supported by the recent advances in genetic testing for CRC whereby specific molecular alterations are identified for the purpose of guiding treatment with targeting therapies such as anti-endothelial growth factor receptor monoclonal antibodies.


Subject(s)
Antibodies, Monoclonal , Biomarkers , Carcinogenesis , Chromosomal Instability , Colorectal Neoplasms , Diagnosis , Epigenomics , Genetic Testing , Genetics , Humans , Microsatellite Instability , Pathology, Molecular , Phenotype
18.
Article in English | WPRIM | ID: wpr-14696

ABSTRACT

BACKGROUND: Aneuploidy has been suggested as one of the major causes of cancer from the time of Boveri. In support of this notion, many studies have shown that cancer cells exhibit aneuploidy. However, there are evidences that do not support the aneuploidy hypothesis. We have previously reported that the spindle assembly checkpoint protein BubR1 is acetylated in mitosis and that the acetylation of BubR1 is crucial for checkpoint maintenance and chromosome-spindle attachment. Mice heterozygous for acetylation-deficient BubR1 (K243R/+) spontaneously develop cancer with chromosome instability. As K243R/+ mice develop hepatocellular carcinoma, we set out to test if chromosome mis-segregation was the cause of their liver cancer. METHODS: Primary hepatocytes in the regenerating liver after partial hepatectomy (PH) were analyzed and compared for various mitotic parameters. RESULTS: Primary hepatocytes isolated from K243R/+ mice after PH displayed a marked increase of chromosome misalignment, accompanied by an increase of micronuclei. In comparison, the number of nuclei per cell and the centrosome numbers were not different between wild-type and K243R/+ mice. Taken together, chromosome mis-segregation provokes tumorigenesis in mouse liver. CONCLUSION: Our results corroborate that PH provides a reliable tool for assessing mitotic infidelity and cancer in mice.


Subject(s)
Acetylation , Aneuploidy , Animals , Carcinogenesis , Carcinoma, Hepatocellular , Centrosome , Chromosomal Instability , Hepatectomy , Hepatocytes , Hydrogen-Ion Concentration , Liver , Liver Neoplasms , M Phase Cell Cycle Checkpoints , Mice , Mitosis
19.
Chinese Journal of Cancer ; (12): 594-603, 2013.
Article in English | WPRIM | ID: wpr-320546

ABSTRACT

Studies over the past decades have uncovered fusion genes, a class of oncogenes that provide immense diagnostic and therapeutic advantages because of their tumor-specific expression. Originally associated with hemotologic cancers, fusion genes have recently been discovered in a wide array of solid tumors, including sarcomas, carcinomas, and tumors of the central nervous system. Fusion genes are attractive as both therapeutic targets and diagnostic tools due to their inherent expression in tumor tissue alone. Therefore, the discovery and elucidation of fusion genes in various cancer types may provide more effective therapies in the future for cancer patients.


Subject(s)
Chromosomal Instability , Gene Expression Regulation, Neoplastic , Genetic Therapy , Humans , Neoplasms , Diagnosis , Genetics , Therapeutics , Oncogene Proteins, Fusion , Genetics , Oncogenes , Recombination, Genetic , Genetics , Translocation, Genetic , Genetics
20.
Chinese Journal of Pediatrics ; (12): 122-125, 2013.
Article in Chinese | WPRIM | ID: wpr-359789

ABSTRACT

<p><b>OBJECTIVE</b>Fanconi anemia (FA) is characterized by bone marrow failure, congenital abnormalities and predisposition to neoplasia. Hypersensitivity of FA cells to the clastogenic effect of mitomycin C (MMC) provides a unique marker for the diagnosis before the beginning of hematological manifestations. The aim of this study was to evaluate the relationship between Single-Cell Gel Electrophoresis (SCGE) and mitomycin C-induced chromosomal breakage in children with FA.</p><p><b>METHOD</b>Between January 2007 and June 2011, 248 children (< 15 years) with hypocytosis were included. Chromosomal breakage was induced by MMC 0 ng/ml, 40 ng/ml, and 80 ng/ml. SCGE was performed at the same time. We analyzed the results of the two methods and compared with each other. The receiver operating characteristic (ROC) curve was used to evaluate the parameters in SCGE.</p><p><b>RESULT</b>Seventeen patients were diagnosed as FA and 231 as non-FA. Chromosomal breakage was found to be significantly higher in FA patients [(32.2 ± 4.8)%] than non-FA [(19.9 ± 3.0)%] and controls[(21.6 ± 4.8)%] when induced by MMC 80 ng/ml. The parameters of SCGE were significantly different between FA patients and non-FA or controls. All the parameters were rectilinearly correlated with MMC (P = 0.000). The most closely correlated parameter was the rate of comet cell (r = 0.848, P = 0.000). The results of ROC curves suggested the comet cell rate (0.999) was more important.</p><p><b>CONCLUSION</b>SCGE might be used to discriminate between FA and non-FA individuals. The relationship between SCGE and MMC-induced chromosomal breakage was significant. The rate of comet cell was the important parameter.</p>


Subject(s)
Adolescent , Anemia, Aplastic , Diagnosis , Case-Control Studies , Child , Child, Preschool , Chromosomal Instability , Chromosome Breakage , Comet Assay , Methods , DNA Damage , Diagnosis, Differential , Fanconi Anemia , Diagnosis , Genetics , Female , Humans , Infant , Male , Mitomycin , Pharmacology , Mosaicism , Pancytopenia , Diagnosis , Genetics , ROC Curve
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