Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 67
Filter
1.
Clin J Gastroenterol ; 17(1): 12-17, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37934348

ABSTRACT

Recently, the results of gastric cancer treatment have improved; however, its characteristics in adolescents and young adults are not well known. We report the case of a patient with advanced gastric cancer, Fanconi anemia (FA), and primary biliary cholangitis. A 26-year-old woman visited a local physician complaining of epigastralgia. Esophagogastroduodenoscopy revealed edematous changes with poor distension and circumferential thickened folds with erosions in the gastric body. Biopsy results of the lesion specimens revealed poorly differentiated adenocarcinoma. Abdominal contrast-enhanced computed tomography revealed gastric wall with irregular thickness, several nodules in the peritoneal cavity, and a mass lesion in the right ovary. We diagnosed the patient with T4N2M1 stage IV gastric cancer accompanied by peritoneal and ovarian metastases and initiated nivolumab with S-1 plus oxaliplatin as the first-line treatment regimen. Because of immune-related adverse events after one course of systemic treatment, the regimen was changed to ramucirumab combined with nab-paclitaxel chemotherapy as the second-line treatment. After three cycles of weekly nab-paclitaxel with ramucirumab, the decreased platelet count did not recover, and her general condition gradually deteriorated. Comprehensive genome profiling using next-generation sequencing was performed to determine the feasibility of genotype-matched therapies. Alterations in FA complementation group A (FANCA) F1263del (49.1%) and E484Q (12.3%), which encode a key component of the multiprotein FA complex, were identified. The patient died 10 months after treatment initiation. In conclusion, when treating malignancies in adolescent and young adult patients, the genomic background should be considered.


Subject(s)
Fanconi Anemia , Stomach Neoplasms , Female , Humans , Young Adult , Adolescent , Adult , Stomach Neoplasms/complications , Stomach Neoplasms/drug therapy , Stomach Neoplasms/genetics , Fanconi Anemia/drug therapy , Fanconi Anemia/etiology , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Ramucirumab , High-Throughput Nucleotide Sequencing
2.
Zhonghua Yi Xue Za Zhi ; 103(4): 235-241, 2023 Jan 31.
Article in Chinese | MEDLINE | ID: mdl-36660784

ABSTRACT

Fanconi anemia (FA) is an autosomal recessive or X-linked hereditary bone marrow failure disease, in which mutations or deletions of FA-related genes lead to abnormalities in DNA repairment after damage and DNA cross-linking repair. The most common mutation genes include FANCA, FANCC, FANCG, FANCE and FANCF. FA is a disorder with high phenotypic and genotypic heterogeneity and mainly manifests as congenital somatic dysplasia, progressive cytopenia and increased risk of malignant tumors. In recent years, the survival of FA patients has greatly improved with the progress of FA management strategy and treatment. In order to better guide the clinical practice of doctors in China, the Red Blood Cell Disease (Anemia) Group of Chinese Society of Hematology of the Chinese Medical Association reached the"Chinese expert consensus on the diagnosis and treatment of Fanconi anemia (version 2022)"by widely collecting experts' suggestions and referring to the latest literature of FA, aiming to further standardize the diagnosis and treatment of FA in China.


Subject(s)
Fanconi Anemia , Humans , Consensus , Fanconi Anemia/diagnosis , Fanconi Anemia/therapy , Fanconi Anemia/etiology , Genotype , Mutation
3.
Transplant Cell Ther ; 29(3): 164.e1-164.e9, 2023 03.
Article in English | MEDLINE | ID: mdl-35995393

ABSTRACT

Hematopoietic stem cell transplantation (HSCT) is a curative treatment for patients with many different blood and immune diseases; however, current treatment regimens contain non-specific chemotherapy and/or irradiation conditioning, which carry both short-term and long-term toxicities. The use of such agents may be particularly harmful for patients with Fanconi anemia (FA), who have genetic mutations resulting in deficiencies in DNA repair, leading to increased sensitivity to genotoxic agents. mAb-based conditioning has been proposed as an alternative conditioning strategy for HSCT that minimizes these toxicities by eliminating collateral tissue damage. Given the high need for improved treatments for FA patients, we aimed to evaluate the efficacy of different αCD117 mAb agents and immunosuppression on hematopoietic stem cell (HSC) depletion and explored their ability to safely establish therapeutic donor hematopoiesis post-HSCT in FA disease models. We evaluated the effects of different concentrations of αCD117 mAbs in vitro and in vivo on HSC growth and depletion. To further assess the efficacy of mAb-based conditioning, Fancd2-/- animals were treated with αCD117 mAb and combination agents with αCD47 mAb and antibody-drug-conjugates (ADCs) for syngeneic HSCT. Immunosuppression αCD4 mAb was added to all in vivo experiments due to a slightly mismatched background between the donor grafts and recipients. Immunosuppressant cocktails were also given to Fancd2-/- animals to evaluate the efficacy of mAb-based conditioning in the haploidentical setting. Statistical analyses were done using the unpaired t-test. We found that antagonistic αCD117 mAbs alone do not deplete host HSCs or enhance HSCT effectively in FA mouse models; however, the potency of αCD117 mAbs can be safely augmented through combination with αCD47 mAbs and with ADCs, both of which lead to profound HSC depletion and establishment of long-term donor engraftment post-syngeneic HSCT. This is the first time these approaches have been tested in parallel in any disease setting, with the greatest donor engraftment observed after CD117-ADC conditioning. Interestingly, our data also suggest that HSC-targeted conditioning is not necessary in HSCT for FA, as high donor HSC engraftment was observed with mAb-based immune suppression alone with immunologically matched and mismatched haploidentical grafts. These results demonstrate the safety and efficacy of several different non-genotoxic mAb-based conditioning strategies in the FA setting. In addition, they show that if sufficient immunosuppression is given to obtain initial donor HSC engraftment, turnover of a majority of the hematolymphoid system can result, likely owing to the survival advantage of wild-type HSCs over FA HSCs. Such non-toxic all-mAb-based conditioning strategies could be transformative for FA patients and those with other hematolymphoid diseases.


Subject(s)
Fanconi Anemia , Hematopoietic Stem Cell Transplantation , Animals , Mice , Fanconi Anemia/etiology , Fanconi Anemia/therapy , Transplantation Conditioning/methods , Hematopoietic Stem Cell Transplantation/adverse effects , Immunosuppressive Agents , Immunosuppression Therapy/methods , Antibodies, Monoclonal
4.
Br J Haematol ; 196(2): 274-287, 2022 01.
Article in English | MEDLINE | ID: mdl-34258754

ABSTRACT

Recent advances have facilitated studies of the clonal architecture of the aging haematopoietic system, and provided clues to the mechanisms underlying the origins of hematopoietic malignancy. Much less is known about the clonal composition of haematopoiesis and its impact in bone marrow failure (BMF) disorders, including Fanconi anaemia (FA). Understanding clonality in FA is likely to inform both the marked predisposition to cancer and the rapid erosion of regenerative reserve seen with this disease. This may also hold broader lessons for haematopoietic stem cell biology in other diseases with a clonal restriction. In this review, we focus on the conceptual basis and available tools to study clonality, and highlight insights in somatic mosaicism and malignant evolution in FA in the context of haematopoietic failure and gene therapy.


Subject(s)
Clonal Evolution/genetics , Fanconi Anemia/etiology , Fanconi Anemia/metabolism , Genetic Variation , Hematopoiesis/genetics , Hematopoietic Stem Cells/metabolism , Mosaicism , Animals , Biomarkers , Cell Differentiation/genetics , Cell Tracking , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/metabolism , Combined Modality Therapy , Cytogenetic Analysis , DNA Damage , Disease Management , Disease Susceptibility , Fanconi Anemia/diagnosis , Fanconi Anemia/therapy , Gene Expression Regulation , Genetic Therapy , Hematopoietic Stem Cells/cytology , Humans , Molecular Imaging , Signal Transduction
5.
Cancer ; 125(22): 3936-3946, 2019 Nov 15.
Article in English | MEDLINE | ID: mdl-31390058

ABSTRACT

Fanconi anemia (FA) is a rare inherited genetic condition that may lead to bone marrow failure, leukemia, and/or solid tumors. It is caused by the loss of function of at least 1 gene of the FA/BRCA pathway, which is necessary for DNA repair. Patients with FA have a 200-fold to 1000-fold risk of developing head and neck cancer, mainly oral squamous cell carcinoma (OSCC), and of doing so at a much younger age than individuals within the general population. Also, patients who have FA with OSCC have poor overall survival rates, reinforcing the necessity to detect OSCC early. The scope of the current review is to provide an update on OSCC in patients with FA.


Subject(s)
Fanconi Anemia/complications , Fanconi Anemia/epidemiology , Mouth Neoplasms/epidemiology , Mouth Neoplasms/etiology , Combined Modality Therapy , Disease Management , Disease Susceptibility , Fanconi Anemia/diagnosis , Fanconi Anemia/etiology , Genetic Predisposition to Disease , Humans , Mouth Neoplasms/diagnosis , Mouth Neoplasms/therapy , Risk Factors , Treatment Outcome
6.
Trends Mol Med ; 25(3): 167-170, 2019 03.
Article in English | MEDLINE | ID: mdl-30744929

ABSTRACT

Fanconi anemia is a rare, cancer-prone disease with mutations in 22 genes. The primary defect results in altered DNA repair mechanisms that fuel a severe proinflammatory condition in the bone marrow, leading to cellular depletion of the hematopoietic system and eventually to bone marrow failure. During the past three decades, a plethora of dysfunctions have been highlighted in the Fanconi anemia phenotype, but recent research allows us to glimpse an even more complex scenario where defective lipid metabolism could have important consequences in hematopoietic stem cell differentiation.


Subject(s)
Fanconi Anemia/etiology , Fanconi Anemia/metabolism , Animals , Cell Transformation, Neoplastic , Disease Progression , Disease Susceptibility , Fanconi Anemia/pathology , Genetic Predisposition to Disease , Humans , Lipid Metabolism , Research
7.
Blood Rev ; 31(3): 93-99, 2017 05.
Article in English | MEDLINE | ID: mdl-27760710

ABSTRACT

Fanconi anemia (FA) is a rare autosomal and X-linked genetic disease characterized by congenital abnormalities, progressive bone marrow failure (BMF), and increased cancer risk during early adulthood. The median lifespan for FA patients is approximately 33years. The proteins encoded by the FA genes function together in the FA-BRCA pathway to repair DNA damage and to maintain genome stability. Within the past two years, five new FA genes have been identified-RAD51/FANCR, BRCA1/FANCS, UBE2T/FANCT, XRCC2/FANCU, and REV7/FANCV-bringing the total number of disease-causing genes to 21. This review summarizes the discovery of these new FA genes and describes how these proteins integrate into the FA-BRCA pathway to maintain genome stability and critically prevent early-onset BMF and cancer.


Subject(s)
Bone Marrow/metabolism , Bone Marrow/pathology , Fanconi Anemia/etiology , Fanconi Anemia/metabolism , BRCA1 Protein/genetics , BRCA1 Protein/metabolism , DNA Damage , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Fanconi Anemia/pathology , Fanconi Anemia Complementation Group Proteins/genetics , Fanconi Anemia Complementation Group Proteins/metabolism , Genomic Instability , Homologous Recombination , Humans , Mad2 Proteins/genetics , Mad2 Proteins/metabolism , Mutation , Rad51 Recombinase/genetics , Rad51 Recombinase/metabolism , Signal Transduction , Ubiquitin/metabolism , Ubiquitin-Conjugating Enzymes/genetics , Ubiquitin-Conjugating Enzymes/metabolism
8.
Laryngoscope ; 126(4): 870-9, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26484938

ABSTRACT

OBJECTIVES/HYPOTHESIS: To describe the management and outcomes of Fanconi anemia (FA) patients with head and neck squamous cell carcinoma. STUDY DESIGN: Cohort study. METHODS: Demographic information, prognostic factors, therapeutic management, and survival outcomes for FA patients enrolled in the International Fanconi Anemia Registry who developed head and neck squamous cell carcinoma (HNSCC) were analyzed. RESULTS: Thirty-five FA patients were diagnosed with HNSCC at a mean age of 32 years. The most common site of primary cancer was the oral cavity (26 of 35, 74%). Thirty patients underwent surgical resection of the cancer. Sixteen patients received radiation therapy with an average radiation dose of 5,050 cGy. The most common toxicities were high-grade mucositis (9 of 16, 56%), hematologic abnormalities (8 of 16, 50%), and dysphagia (8 of 16, 50%). Three patients received conventional chemotherapy and had significant complications, whereas three patients who received targeted chemotherapy with cetuximab had fewer toxicities. The 5-year overall survival rate was 39%, with a cause-specific survival rate of 47%. CONCLUSIONS: Fanconi anemia patients have a high risk of developing aggressive HNSCC at an early age. Fanconi anemia patients can tolerate complex ablative and reconstructive surgeries, but careful postoperative care is required to reduce morbidity. The treatment of FA-associated HNSCC is difficult secondary to the poor tolerance of radiation and chemotherapy. However, radiation should be used for high-risk cancers due to the poor survival in these patients. LEVEL OF EVIDENCE: 4.


Subject(s)
Carcinoma, Squamous Cell/complications , Fanconi Anemia/etiology , Fanconi Anemia/therapy , Head and Neck Neoplasms/complications , Adolescent , Adult , Carcinoma, Squamous Cell/therapy , Female , Follow-Up Studies , Head and Neck Neoplasms/therapy , Humans , Male , Middle Aged , Risk Factors , Survival Rate , Treatment Outcome
9.
Ginekol Pol ; 86(2): 150-4, 2015 Feb.
Article in Polish | MEDLINE | ID: mdl-25807841

ABSTRACT

We reviewed the literature on the relationship between the Fanconi anemia pathway (FA) and response to chemotherapy in patients with ovarian cancer. Despite continuous developments in medicine, ovarian cancer remains a challenge for both, physicians and researchers seeking ways to achieve better results of chemotherapy combined with other targeted therapies. Clinically relevant resistance to chemotherapy is a major problem in treating ovarian cancer. Researchers continue to investigate mechanisms responsible for drug resistance in order to develop better therapeutic methods against ovarian cancer. Among the resistance mechanisms, defects in DNA repair, including the FA pathway may be important in increasing the sensitivity of ovarian cancer cells to chemotherapy agents at the clinical level. A growing number of data has shown that disruption of the FA genes may be a useful predictor of OC sensitivity to chemotherapy agents whose activity is based on DNA crosslinking mechanisms.


Subject(s)
Drug Resistance, Neoplasm , Fanconi Anemia/etiology , Fanconi Anemia/metabolism , Ovarian Neoplasms/complications , Ovarian Neoplasms/drug therapy , Antineoplastic Agents/administration & dosage , DNA Repair , DNA Replication , Female , Humans , Ovarian Neoplasms/metabolism , Signal Transduction/drug effects , Women's Health
10.
Nat Commun ; 5: 4330, 2014 Jul 07.
Article in English | MEDLINE | ID: mdl-24999918

ABSTRACT

Fanconi anaemia (FA) is a recessive disorder characterized by genomic instability, congenital abnormalities, cancer predisposition and bone marrow (BM) failure. However, the pathogenesis of FA is not fully understood partly due to the limitations of current disease models. Here, we derive integration free-induced pluripotent stem cells (iPSCs) from an FA patient without genetic complementation and report in situ gene correction in FA-iPSCs as well as the generation of isogenic FANCA-deficient human embryonic stem cell (ESC) lines. FA cellular phenotypes are recapitulated in iPSCs/ESCs and their adult stem/progenitor cell derivatives. By using isogenic pathogenic mutation-free controls as well as cellular and genomic tools, our model serves to facilitate the discovery of novel disease features. We validate our model as a drug-screening platform by identifying several compounds that improve hematopoietic differentiation of FA-iPSCs. These compounds are also able to rescue the hematopoietic phenotype of FA patient BM cells.


Subject(s)
Drug Evaluation, Preclinical/methods , Fanconi Anemia/etiology , Fanconi Anemia/pathology , Models, Biological , Stem Cells/pathology , Cell Differentiation , Epigenesis, Genetic , Fanconi Anemia/drug therapy , Fanconi Anemia Complementation Group A Protein/genetics , Humans , Induced Pluripotent Stem Cells , Male , Young Adult
12.
Dis Model Mech ; 6(1): 40-7, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23268537

ABSTRACT

Fanconi anaemia (FA) is a rare autosomal recessive or X-linked inherited disease characterised by an increased incidence of bone marrow failure (BMF), haematological malignancies and solid tumours. Cells from individuals with FA show a pronounced sensitivity to DNA interstrand crosslink (ICL)-inducing agents, which manifests as G2-M arrest, chromosomal aberrations and reduced cellular survival. To date, mutations in at least 15 different genes have been identified that cause FA; the products of all of these genes are thought to function together in the FA pathway, which is essential for ICL repair. Rapidly following the discovery of FA genes, mutant mice were generated to study the disease and the affected pathway. These mutant mice all show the characteristic cellular ICL-inducing agent sensitivity, but only partially recapitulate the developmental abnormalities, anaemia and cancer predisposition seen in individuals with FA. Therefore, the usefulness of modelling FA in mice has been questioned. In this Review, we argue that such scepticism is unjustified. We outline that haematopoietic defects and cancer predisposition are manifestations of FA gene defects in mice, albeit only in certain genetic backgrounds and under certain conditions. Most importantly, recent work has shown that developmental defects in FA mice also arise with concomitant inactivation of acetaldehyde metabolism, giving a strong clue about the nature of the endogenous lesion that must be repaired by the functional FA pathway. This body of work provides an excellent example of a paradox in FA research: that the dissimilarity, rather than the similarity, between mice and humans can provide insight into human disease. We expect that further study of mouse models of FA will help to uncover the mechanistic background of FA, ultimately leading to better treatment options for the disease.


Subject(s)
Fanconi Anemia/genetics , Animals , Congenital Abnormalities/genetics , Disease Models, Animal , Fanconi Anemia/etiology , Fanconi Anemia/metabolism , Fanconi Anemia Complementation Group Proteins/genetics , Fanconi Anemia Complementation Group Proteins/metabolism , Genes, Lethal , Humans , Mice , Mice, Mutant Strains , Mutation , Neoplasms/genetics , Species Specificity , Telomere/genetics
13.
PLoS Comput Biol ; 8(6): e1002531, 2012.
Article in English | MEDLINE | ID: mdl-22761553

ABSTRACT

Many human diseases, arising from mutations of disease susceptibility genes (genetic diseases), are also associated with viral infections (virally implicated diseases), either in a directly causal manner or by indirect associations. Here we examine whether viral perturbations of host interactome may underlie such virally implicated disease relationships. Using as models two different human viruses, Epstein-Barr virus (EBV) and human papillomavirus (HPV), we find that host targets of viral proteins reside in network proximity to products of disease susceptibility genes. Expression changes in virally implicated disease tissues and comorbidity patterns cluster significantly in the network vicinity of viral targets. The topological proximity found between cellular targets of viral proteins and disease genes was exploited to uncover a novel pathway linking HPV to Fanconi anemia.


Subject(s)
Disease/etiology , Models, Biological , Virus Diseases/complications , Computational Biology , Disease/genetics , Fanconi Anemia/etiology , Fanconi Anemia/genetics , Fanconi Anemia/virology , Genetic Predisposition to Disease , Herpesvirus 4, Human/metabolism , Herpesvirus 4, Human/pathogenicity , Host-Pathogen Interactions/genetics , Host-Pathogen Interactions/physiology , Human papillomavirus 16/metabolism , Human papillomavirus 16/pathogenicity , Humans , Protein Interaction Maps , Viral Proteins/metabolism
14.
Blood ; 120(2): 323-34, 2012 Jul 12.
Article in English | MEDLINE | ID: mdl-22653977

ABSTRACT

Bone marrow failure is a nearly universal complication of Fanconi anemia. The proteins encoded by FANC genes are involved in DNA damage responses through the formation of a multisubunit nuclear complex that facilitates the E3 ubiquitin ligase activity of FANCL. However, it is not known whether loss of E3 ubiquitin ligase activity accounts for the hematopoietic stem cell defects characteristic of Fanconi anemia. Here we provide evidence that FANCL increases the activity and expression of ß-catenin, a key pluripotency factor in hematopoietic stem cells. We show that FANCL ubiquitinates ß-catenin with atypical ubiquitin chain extension known to have nonproteolytic functions. Specifically, ß-catenin modified with lysine-11 ubiquitin chain extension efficiently activates a lymphocyte enhancer-binding factor-T cell factor reporter. We also show that FANCL-deficient cells display diminished capacity to activate ß-catenin leading to reduced transcription of Wnt-responsive targets c-Myc and Cyclin D1. Suppression of FANCL expression in normal human CD34(+) stem and progenitor cells results in fewer ß-catenin active cells and inhibits expansion of multilineage progenitors. Together, these results suggest that diminished Wnt/ß-catenin signaling may be an underlying molecular defect in FANCL-deficient hematopoietic stem cells leading to their accelerated loss.


Subject(s)
Fanconi Anemia Complementation Group L Protein/metabolism , beta Catenin/metabolism , Animals , Cell Line , Cell Nucleus/metabolism , Cyclin D1/metabolism , Fanconi Anemia/etiology , Fanconi Anemia/genetics , Fanconi Anemia/metabolism , Fanconi Anemia/pathology , Fanconi Anemia Complementation Group C Protein/deficiency , Fanconi Anemia Complementation Group C Protein/genetics , Fanconi Anemia Complementation Group C Protein/metabolism , Fanconi Anemia Complementation Group L Protein/deficiency , Fanconi Anemia Complementation Group L Protein/genetics , Fetal Blood/cytology , Fetal Blood/metabolism , HEK293 Cells , Hematopoietic Stem Cells/metabolism , Hematopoietic Stem Cells/pathology , Humans , Mice , Mice, Knockout , Models, Biological , Pluripotent Stem Cells/metabolism , Pluripotent Stem Cells/pathology , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Signal Transduction , TCF Transcription Factors/metabolism , Ubiquitination , beta Catenin/chemistry
15.
Radiother Oncol ; 101(1): 190-7, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21722982

ABSTRACT

BACKGROUND AND PURPOSE: Hypoxia is a common feature of the microenvironment of solid tumors which has been shown to promote malignancy and poor patient outcome through multiple mechanisms. The association of hypoxia with more aggressive disease may be due in part to recently identified links between hypoxia and genetic instability. For example, hypoxia has been demonstrated to impede DNA repair by down-regulating the homologous recombination protein RAD51. Here we investigated hypoxic regulation of UBE2T, a ubiquitin ligase required in the Fanconi anemia (FA) DNA repair pathway. MATERIALS AND METHODS: We analysed UBE2T expression by microarray, quantitative PCR and western blot analysis in a panel of cancer cell lines as a function of oxygen concentration. The importance of this regulation was assessed by measuring cell survival in response to DNA damaging agents under normoxia or hypoxia. Finally, HIF dependency was determined using knockdown cell lines and RCC4 cells which constitutively express HIF1α. RESULTS: Hypoxia results in rapid and potent reductions in mRNA levels of UBE2T in a panel of cancer cell lines. Reduced UBE2T mRNA expression is HIF independent and was not due to changes in mRNA or protein stability, but rather reflected reduced promoter activity. Exposure of tumor cells to hypoxia greatly increased their sensitivity to treatment with the interstrand crosslinking (ICL) agent mitomycin C. CONCLUSIONS: Exposure to hypoxic conditions down-regulates UBE2T expression which correlates with an increased sensitivity to crosslinking agents consistent with a defective Fanconi anemia pathway. This pathway can potentially be exploited to target hypoxic cells in tumors.


Subject(s)
Fanconi Anemia/drug therapy , Fanconi Anemia/metabolism , Hypoxia/metabolism , Signal Transduction/drug effects , Ubiquitin-Conjugating Enzymes/metabolism , Antineoplastic Agents/pharmacology , Blotting, Western , Cell Survival , DNA Repair , Down-Regulation , Fanconi Anemia/etiology , Gene Expression Regulation, Neoplastic , Humans , Hypoxia/complications , Neoplasms/blood supply , Neoplasms/complications , Neoplasms/drug therapy , RNA, Messenger/metabolism , Reference Values , Signal Transduction/genetics , Tumor Cells, Cultured
17.
Carcinogenesis ; 31(12): 2031-8, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20952512

ABSTRACT

Germline mutations in many of the genes that are involved in homologous recombination (HR)-mediated DNA double-strand break repair (DSBR) are associated with various human genetic disorders and cancer. RAD51 and RAD51 paralogs are important for HR and in the maintenance of genome stability. Despite the identification of five RAD51 paralogs over a decade ago, the molecular mechanism(s) by which RAD51 paralogs regulate HR and genome maintenance remains obscure. In addition to the known roles of RAD51C in early and late stages of HR, it also contributes to activation of the checkpoint kinase CHK2. One recent study identifies biallelic mutation in RAD51C leading to Fanconi anemia-like disorder. Whereas a second study reports monoallelic mutation in RAD51C associated with increased risk of breast and ovarian cancer. These reports show RAD51C is a cancer susceptibility gene. In this review, we focus on describing the functions of RAD51C in HR, DNA damage signaling and as a tumor suppressor with an emphasis on the new roles of RAD51C unveiled by these reports.


Subject(s)
Breast Neoplasms/genetics , DNA-Binding Proteins/genetics , Fanconi Anemia/genetics , Genetic Predisposition to Disease , Breast Neoplasms/etiology , DNA Damage , Fanconi Anemia/etiology , Humans , Mutation , Recombination, Genetic
18.
J Investig Dermatol Symp Proc ; 14(1): 8-14, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19675546

ABSTRACT

Progeroid syndromes are a group of diseases characterized by signs of premature aging. These syndromes comprise diseases such as Werner syndrome, Bloom syndrome, Rothmund-Thomson syndrome, Hutchinson-Gilford syndrome, Fanconi anemia, and ataxia-telangiectasia, as well as xeroderma pigmentosum, trichothiodystrophy, and Cockayne syndrome. Clinical symptoms of premature aging are skin atrophy with loss of cutaneous elasticity, dysfunction of cutaneous appendices, degeneration of the central nervous system and an increased susceptibility for malignant tumors. Genetic defects in the repair of DNA damage can lead to progeroid syndromes, and it is becoming increasingly evident that direct DNA damage and indirect damage by highly reactive oxygen species play central roles in aging. The clinical signs of progeroid syndromes and the molecular aspects of UV (ultraviolet radiation)-induced oxidative stress in aging are discussed.Journal of Investigative Dermatology Symposium Proceedings (2009) 14, 8-14; doi:10.1038/jidsymp.2009.6.


Subject(s)
Cockayne Syndrome/etiology , DNA Damage , Ultraviolet Rays/adverse effects , Ataxia Telangiectasia/etiology , Bloom Syndrome/etiology , Cockayne Syndrome/genetics , Cockayne Syndrome/metabolism , DNA Repair , Fanconi Anemia/etiology , Female , Humans , Male , Models, Biological , Oxidative Stress/radiation effects , Progeria/etiology , Rothmund-Thomson Syndrome/etiology , Trichothiodystrophy Syndromes/etiology , Werner Syndrome/etiology , Xeroderma Pigmentosum/etiology
19.
Asian Pac J Cancer Prev ; 9(1): 151-4, 2008.
Article in English | MEDLINE | ID: mdl-18439095

ABSTRACT

The myelodysplastic syndrome (MDS) represents a group of clonal hematological disorders characterized by progressive cytopenia reflecting defects in erythroid, myeloid and mega karyocytic maturation. The incidence of MDS is greter in older age groups. Detailed studies on MDS from India are not available. Cytogenetic study using GTG-banding and FISH revealed 54.5% clonal chromosomal abnormalities. We have carried out chromosomal breakage study from peripheral blood cultures induced with mitomycin C, in karyotypically normal MDS (49) and 15 (30.6%) showed significant (p < 0.001) increase in chromosome damage compared to controls. Among 22 occupationally exposed MDS, 6 (27.3%) showed a high frequency of chromosome breakage while in the non-exposure (n=27) group, high chromosome breakage was noted in 9 (33.3% ) MDS patients. Our results suggest that the high chromosome damage may be due to acquired Fanconi anemia which leads to multiple defects in chromosomes and clonal chromosome anomalies.


Subject(s)
Chromosome Breakage , Myelodysplastic Syndromes/genetics , Alkylating Agents/pharmacology , Blast Crisis , Chromosome Banding , Fanconi Anemia/blood , Fanconi Anemia/etiology , Humans , In Situ Hybridization, Fluorescence , India , Karyotyping , Mitomycin/pharmacology , Myelodysplastic Syndromes/blood
20.
Article in Spanish | LILACS | ID: lil-498358

ABSTRACT

La anemia de Fanconi es un desorden genético recesivo con ambos patrones de herencia, autosómico y ligado al sexo, caracterizada por diferentes malformaciones congénitas, fallo de médula ósea y una elevada predisposición a desarrollar tumores sólidos y leucemia mieloide aguda. Es una enfermedad monogénica con expresión citogenética dada por inestabilidad cromosómica tanto espontánea como provocada por agentes inductores de enlaces cruzados en las cadenas de ADN. Se presentan 2 pacientes masculinos, hermanos, de 5 y 7 años de edad, con malformaciones congénitas e insuficiencia medular. Se les realizó el estudio de rupturas cromosómicas con el uso del diepoxibutano y se observaron múltiples rupturas y figuras radiales, lo que confirmó el diagnóstico.


Fanconi's anemia is a recurrent genetic disorder with both patterns of heredity, autosomal and linked to sex. It is characterized by different congenital malformations, bone marrow failure and an elevated predisposition to develop solid tumors and acute myeloid leukemia. It is a monogenic disease with cytogenetic expression given by chromosomal instability, both spontaneous and provoked by agents inducing cross-links in the DNA chains. Two male siblings aged 5 and 7 years old, with congenital malformations and medullar insufficiency were presented. The study of chromosome rupture was conducted by using diepoxybutane. Multiple ruptures and radial figures were observed, which confirmed the diagnosis.


Subject(s)
Humans , Child, Preschool , Child , Fanconi Anemia/etiology , Chromosomes , Case Reports
SELECTION OF CITATIONS
SEARCH DETAIL
...