TAILIEUCHUNG - Chapter 079. Cancer Genetics (Part 3)

Familial Cancer Syndromes A small fraction of cancers occur in patients with a genetic predisposition. In these families, the affected individuals have a predisposing loss-of-function mutation in one allele of a tumor-suppressor gene or caretaker gene. The tumors in these patients show a loss of the remaining normal allele as a result of somatic events (point mutations or deletions), in agreement with the Knudson hypothesis (Fig. 79-3). Thus, most cells of an individual with an inherited loss-of-function mutation in a tumor-suppressor gene are functionally normal, and only the rare cells that develop a mutation in the remaining normal allele. | Chapter 079. Cancer Genetics Part 3 Familial Cancer Syndromes A small fraction of cancers occur in patients with a genetic predisposition. In these families the affected individuals have a predisposing loss-of-function mutation in one allele of a tumor-suppressor gene or caretaker gene. The tumors in these patients show a loss of the remaining normal allele as a result of somatic events point mutations or deletions in agreement with the Knudson hypothesis Fig. 79-3 . Thus most cells of an individual with an inherited loss-of-function mutation in a tumor-suppressor gene are functionally normal and only the rare cells that develop a mutation in the remaining normal allele will exhibit uncontrolled growth. The normal function of tumor suppressors is to restrain growth to promote differentiation gatekeeper genes or to preserve genome integrity caretaker genes . Roughly 100 syndromes of familial cancer have been reported although many are rare. The majority are inherited as autosomal dominant traits although some of those associated with DNA repair abnormalities xeroderma pigmentosum Fanconi s anemia ataxia telangiectasia are autosomal recessive. Table 79-1 shows a number of cancer predisposition syndromes and the responsible genes. The current paradigm states that the genes mutated in familial syndromes can also be targets for somatic mutations in sporadic noninherited tumors. The study of cancer syndromes has thus provided invaluable insights into the mechanisms of progression for many tumor types. This section examines the case of inherited colon cancer in detail but the same general lessons can be applied to all the cancer syndromes listed in Table 79-1. Table 79-1 Cancer Predisposition Syndromes and Associated Genes Syndrome Gene Chromo some Inherit ance Tumors Ataxia telangiectasia ATM 11q22- q23 AR Breast cancer Autoimmun FAS 10q24 AD Lymphom e lymphoproliferativ e syndrome FASL 1q23 as Bloom syndrome BLM AR Cancer of all types Cowden syndrome PTE N 10q23

• Y học thường thức
• Cancer Genetics
• bệnh học và điều trị
• bài giảng bệnh học
• tài liệu y khoa
• Harrisons Internal Medicine
• Biological information
• Lecture Genetics
• Human genetics
• Somatic mutation
• Genetics of cancer
• Cell division
• Quantitative genetics
• Population genetics
• Evolutionary genetics
• The genetic code
• Genetics in medicine
• Developmental genetics
• Birth defects
• Cancer genetics and genomics
• Risk assessment
• Genetic counseling
• Prenatal diagnosis and screening
• Personalized health care
• USMLE road map Genetics
• Mitochondrial dysfunction
• Congenital changes
• Genetics and cancer
• Genetics and common diseases
• Surgical Treatment
• Laparoscopic Surgery
• Severe Ulcerative Colitis
• Drug Therapy
• Biologic Drugs
• Ulcerative Colitis
• Chronic Myelogenous Leukemia
• Colorectal Cancer
• Neurodegenerative Diseases
• Teratogenesi
• Medical Genetics
• Diagnostic Techniques
• Basic Genetics
• Breast cancer management
• Gross anatomy
• The breast
• Breast cancer epidemiology
• Hereditary breast cancer genetics
• Prediction techniques
• Breast cancer screening
• HIV infection
• Testicular cancer
• Penile cancer
• associated dermatoses
• Cutaneous melanoma
• Molecular Carcinogenesis
• Molecular Epidemiology
• Cancer Disparities in Appalachia
• Environmental Factors
• Breast Cancer Genetics
• ABC of colorectal cancer
• Clinical genetics
• The surgeon matter
• Adjuvant therapy
• The role of primary care
• BMC Cancer
• Young onset colorectal cancer
• Clinicopathological characteristics
• Genetic referral
• Microsatellite instability
• Breast cancer susceptibility
• Haplotype analysis
• Functional analysis
• Multifocal bladder cancer
• Next generation sequencing
• APOBEC deaminase
• Gynaecological oncology
• Pathogenic sequence variants
• BMC Genetics
• Liver cancer
• RNA sequencing
• Potential molecular mechanism
• Cancer hypoxia