Bases moleculares del Cncer Hereditario del Consejo Gentico

Bases moleculares del Cáncer Hereditario, (del Consejo Genético y de Identificación de los Principales Síndromes) Miguel Urioste Genética Humana Centro Nacional de Investigaciones Oncológicas (CNIO)

Breast Cancer. Sporadic and hereditary cases 85 BC d. 50 64 OC d. 41 39 a 54 a 28 22 52 BC d. 47 26 24 18 50 BC d. 38 21 17 49 a 11 8 Slide provided by Dr. Ignacio Blanco

Characteristic of almost all human cancers Hereditary cancers Mutator hypothesis Genomic Instability ¿? Sporadic cancers

Types of Genomic Instability CIN (chromosomal instability) Non-CIN (MSI, GC/TA transversions…) Negrini et al. Nat Rev Mol Cell Biol 11: 220, 2010

Chromosomal Instability (CIN)

Microsatellite Instability (MSI) and Mismatch Repair Genes Fig. 1 The MMR system. During DNA replication, insertions or deletions of one or more nucleotides and single nucleotide mismatches may occur. For example: (A) A single nucleotide mismatch occurs (GT in red). (B) MSH 2 and MSH 6 form a heterodimer and recognize the mismatch. (C) MLH 1 and PMS 2 dimerize and bind to the MSH 2 MSH 6 complex. (D) The complex of four proteins activates an exonuclease to perform the DNA repair Fig. 2 MSI. A schematic microsatellite is indicated (poly A track). When the tumour cells have an intact MMR system the size of the microsatellite will be the same in DNA isolated from normal (N) and from tumour (T) cells: microsatellite stable (MSS) tumour. In case of a defect in MMR the size of the microsatellite (number of repeat units) can change (in most cases becomes shorter) when comparing N with T DNA: microsatellite unstable (MSI) tumour. Asterisks indicate the microsatellite unstable tumour DNA fragment. van Lier et al. J Cell Mol Med 14: 181, 2010

DNA Repair Pathways

Genetic predisposition for cancer Loss of the remaining wild-type allele Carcinogens Hormone and reproductive factors Genomic instability in precancerous lesions Mutator hypothesis (caretaker genes inactivation) Tumor development Diet

Genomic Instability in sporadic human cancers - 69 -97% of human sporadic cancers did not have mutations in caretaker genes in various studies. - These studies argues against the mutator hypothesis for sporadic cancers. - Oncogenes induce genomic instability by DNA replication stress. Specific genomic sites, called common fragile sites, are particularly sensitive to DNA replication stress.

Genomic Instability as a hallmark of cancer Hanahan & Weinberg. Cell 100: 57, 2000 Luo et al. Cell 136: 823, 2009 Negrini et al. Nat Rev Mol Cell Biol. 11: 220, 2010

HBOC. BRCA 1/2 genes Figure 3. Examples of interactions involving BRCA 1 and BRCA 2 proteins stressing the general nature of their functions and some interactions with BRCA 1. The exact order of events and understanding of these interactions are still evolving. Bernard Friedenson. http: //www. medscape. com/viewarticle/505347_3

Molecular mechanisms of colorectal carcinoma development Fig. 1 Schematic represent several overlapping ways to describe the development of colorectal carcinoma. The red circles represent mechanisms based on putative initiating factors (the suppressor and mutator pathways). The blue circles represent mechanisms based on the precursor lesion (the conventional adenoma-carcinoma sequence and serrated pathways). The yellow circles represent currently poorly characterized pathways. (Key: FAP = familial adenomatous polyposis; CIMP+ = Cp. G island methylator phenotype positive; CIMP- = Cp. G island methylator phenotype negative; MSI-H = high degree of microsatellite instability; MSI-L = low degree of microsatellite instability; MSS = microsatellite stable; TSA = traditional serrated adenoma. ) Snover DC. Hum Pathol, Sep 23, 2010

Hereditary Breast and Ovarian Cancer (HBOC) Breast cancer

Inheritance Mendelian patterns Autosomal, dominant and recessive Sex chromosome inheritance, X-linked, and Ylinked “Non-Traditional” patterns Mosaicism Mitochondrial inheritance Microdeletion syndromes Genomic imprinting Uniparental disomy Trinucleotide repeats

“Non-Traditional Inheritance - High rate (2%) of gonadal mosaicism in Tuberous Sclerosis Complex 1 - Mitochondrial DNA G 10398 A polymorphism could increase breast cancer risk 2 - 17 q 11. 2 deletion explains 5 -10% of Neurofibromatosis type 1 patients 3 - Maternal imprinting has been described in SDHD gene (familial paraganglioma) 4 - Constitutional dup 11 p 15 is associated with hemihiperplasia and cancer risk 5 Roach and Saparagana. Neurol, 2004 - Trinucleotide repeat dynamic mutation identifying susceptibility in. J Child familial 1 Darvishi et al. Cancer Letters, 2007 3 Douglas et al. Nat Genet, 2007 4 Hensen et al. Oncogene, 2004 5 Shuman et al. Am J Med Genet, 2006 6 Auer et al. B J Haematol, 2007 2 chronic lymphocytic leukaemia 6

Opening Plenary Session The cancer genome Eric S. Lander, D. Phil. Broad Institute of MIT and Harvard, Cambridge, MA

Common cancer CNVs in the human genome The chromosomes containing common cancer CNVs in the human genome are shown. Loci are highlighted in green if they were found to contain a cancer-related gene that is overlapped or encompassed by a CNV. Shlien A and Malkin D. Genome Med, 16: 62, 2009 Shlien A and Malkin D. Curr Opin Oncol, 22: 55, 2010

Excessive CNVs in Li-Fraumeni Fig. 1. Increased CNV frequency in LFS. (A) To establish a baseline CNV frequency (CNVs per genome), genomic DNA from a large healthy population (n =770) was assessed for CNVs by using the Affymetrix Nsp SNP microarray. The distribution of CNV frequencies in the normal population is shown. Most individuals have few CNVs (median 3). Seventy-five percent of the healthy population have four or fewer CNVs. (B) A significant increase in CNVs was observed in TP 53 mutation carriers as compared with controls (P=0. 01). The TP 53 wild-type group displayed no significant increase in CNV frequency (P= 0. 994). As shown, the mean CNV frequencies are 2. 93, 3. 40, and 12. 19 CNVs per genome in the control (n= 70), TP 53 wild type (n =20), and TP 53 mutation carrier (n=31) groups, respectively. Error bars represent SEM. (C) Bar graph of CNV frequency in controls (n= 70), TP 53 wild-type individuals (n= 20), TP 53 mutation carriers unaffected by cancer (n=8), and TP 53 mutation carriers affected by cancer (n=23). Both the unaffected and affected groups had significantly increased CNV frequencies as compared with controls (P= 0. 009 and P= 0. 046, respectively). There is also an increase in CNVs in the affected group as compared with the unaffected TP 53 mutation carriers, although not meeting statistical significance because of the loss of power caused by subdividing the group into small cohorts. Error bars represent SEM. Shlien et al. PNAS, 105: 11264, 2008

HBOC. Incomplete penetrance and variable expressivity † 80 dx 45 BRCA 1+ † 60 61 BRCA 1+ dx 59 BRCA 1+ 38 Dx 35 BRCA 1+ † 58 Dx 35, 45 BRCA 1+ † 79 dx 67 BRCA 1+ BRCA 1 - BRCA 1+ 33 34 dx 33 dx 30 BRCA 1+ Breast cancer Prostate cancer Bilateral breast cancer Pancreas cancer 81 dx 69 BRCA 1 - 30 BRCA 1 - Ovary cancer IBCCS: International BRCA 1/2 Carrier Cohort Study CIMBA: Consortium of Investigators of Modifiers of BRCA 1 and BRCA 2

HBOC. IBCCS studies International BRCA 1/2 Carrier Cohort Study

HBOC. Genetic modifiers of the risk Nature Genetics | Letter A locus on 19 p 13 modifies risk of breast cancer in BRCA 1 mutation carriers and is associated with hormone receptor–negative breast cancer in the general population Antonis C Antoniou, Xianshu Wang, Zachary S Fredericksen, Lesley Mc. Guffog, Robert Tarrell, Olga M Sinilnikova, Sue Healey, Jonathan Morrison, Christiana Kartsonaki, Timothy Lesnick, Maya Ghoussaini, Daniel Barrowdale, EMBRANCE, Susan Peock, Margaret Cook, Clare Oliver, Debra Frost, Diana Eccles, D Gareth Evans, Ros Eeles, Louise Izatt, Carol Chu, Fiona Douglas, Joan Paterson, Dominique Stoppa-Lyonnet, et al. Published online 19 September 2010

HBOC. Genetic testing 75% BRCA 1/2 negative 5 -10% 20 -25% BRCA 1/2 90 -95% Sporadic BC 5% TP 53, PTEN, STK 11, CHK 2, ATM, BRIP 1, PALB 2, RAD 51 C, Otros

Hereditary Breast Cancer. Susceptibility genes High penetrance BRCA 1, BRCA 2 - Responsible of 25% of hereditary cases - High risk to develop breast/ovarian cancers TP 53 - Li-Fraumeni syndrome features - High risk to develop breast and other cancers PTEN - PTEN-hamartoma syndrome features - High risk to develop breast (50%), thyroid and endometrial cancers Moderate penetrance CHEK 2, ATM, BRIP (FANCJ), PALB 2 (FANCN), RAD 50, NBS 1, RAD 51 C* - 2 x population risk to breast cancer * Meindl A et al. Nat Gente 42: 410, 2010

Li-Fraumeni syndrome. Associated tumors www-p 53. iarc. fr/index. html Curso doctorado, CNIO, 24 Marzo 2008

PTEN hamartoma tumour syndrome (PHTS) Cowden syndrome Bannayan-Riley-Ruvalcaba syndrome Proteus syndrome and Proteus-like Other entities Curso doctorado, CNIO, 24 Marzo 2008

Cowden syndrome. - AD, familial cases represent 1050% - f = 1/200. 000 - Penetrance: 99% at the age of 30 - Variable expressivity - Operational criteria (ICSC) Curso doctorado, CNIO, 24 Marzo 2008

Cowden syndrome. A pleiotropic syndrome

Cowden syndrome. Operational criteria International Cowden Consortium 1995, 2000 Curso doctorado, CNIO, 24 Marzo 2008

PHTS. PTEN germline mutations CS CS BR BR CS CS MT CS sporadic CS familial MT multiple tumors BR familial BR sporadic Curso doctorado, CNIO, 24 Marzo 2008

Developmental abnormalities and juvenile myelomonocitic leukemia New dominant developmental disorder and increased risk of cancer Impaired growth Developmental delay Cryptorchidism CAL spots Hearing loss Predisposition to Juvenile Myelomonocytic Leukemia (JMML) Germline missense CBL gene mutations 21 children with JMML 17 with germline CBL gene mutation 13 informative families: 7 with autosomal dominat inheritance JMML specimens show loss of normal CBL allele through acquired isodisomy 11 q Niemeyer et al. Nat Genet, Sep 2010

Developmental abnormalities and juvenile myelomonocitic leukemia Figure 1 Autosomal dominant germline mutations in CBL are associated with a phenotype, GM-CSF hypersensitivity and vasculitis. (a) Angiograms from the aorta and left subclavian artery from subject D 048 nine months after the diagnosis of Takayasu arteritis type III. (b) The family tree of UPN 1333, whose diseased bone marrow showed a homozygous CBL c. 1111 T>C (red) mutation as well as a heterozygous lesion from his buccal swab (black). Only women appear to be heterozygote carriers, and only boys appear to be affected by JMML in this family. (c) The bone marrow of UPN 1125 showed a homozygous CBL mutation. Her mother (III: 5) is a known carrier, and two male cousins died from JMML (III: 6, III: 7). (d) GM-CSF hypersensitivity response on a colony assay for subjects with CBL mutations (n = 3) versus normal (n = 13). Error bars represent s. e. m. (e) A toddler (D 703) diagnosed with JMML and a homozygous mutation at p. 384 C>R. She displays frontal bossing, downslanting palpebral fissures, hypertelorism, and a low nasal bridge. Her father harbors a heterozygous mutation at p. 384 C>R (Supplementary Fig. 1 d). Both father and daughter also show bilateral ptosis. Informed consent to publish the photograph in e was obtained from the subject’s father. Niemeyer et al. Nat Genet, Sep 2010

HBOC. Negative results BRCA 1/2 - “… then. . , my case isn´t hereditary. Is it so, doctor? ”

Negative results Other mechanisms of inactivation? Other genes? Next generation sequencing

Conclusions - Hereditary cancer has been linked to mutations in DNA repair genes - High-throughput technologies provide growing insights into genomic organization - There are potentially many different mechanisms that can disrupt or modify normal gene function - Genetic counselling is the best tool for family assessment, but it is a complex process - It´s clinically relevant to promote research in hereditary cancer To define better both effects and risks associated to mutations in specific genes To identify new susceptibility genes To improve the surveillance of carriers and the treatment of patients