武汉大学：《遗传学》课程教学课件（英文讲稿）Chapter 19A The Genetics of Cancer

Chapter19The Genetics of Cancer19-1

Copyright © The McGraw-Hill Companies, Inc. Permission required to reproduce or display 19-1 The Genetics of Cancer The Genetics of Cancer Chapter 19

Sectionsto study19.3How cell division is normally controlled19.1Characteristics of cancer cells19.2Thegeneticbasis of cancers19.4 Howmutations cause cancer phenotypes19.5Personalizedcancertreatment19-2

Copyright © The McGraw-Hill Companies, Inc. Permission required to reproduce or display 19-2 Sections to study Sections to study 19.3 How cell division is normally controlled 19.3 How cell division is normally controlled 19.1 Characteristics of cancer cells 19.1 Characteristics of cancer cells 19.2 The genetic basis of cancers 19.2 The genetic basis of cancers 19.4 How mutations cause cancer phenotypes 19.4 How mutations cause cancer phenotypes 19.5 Personalized cancer treatment 19.5 Personalized cancer treatment

G,:Cell grows insize,prepares forDNA replication19.3 How cellCentrosomeS:DNAreplicationCell membranedivision is normallyDNANuclearcontrolledmembraneDaughtercellsGa:Cellpreparesfor divisionCell divisionMitosisCytokinesisSpindlepoleCondensedchromosomeMitoticspindleM:Mitosis1.Breakdownofnuclearmembrane2.Condensation ofchromosomes3.Attachmentofchromosomestomitoticspindles

Copyright © The McGraw-Hill Companies, Inc. Permission required to reproduce or display 19-3 19.3 How cell 19.3 How cell division is normally division is normally controlled controlled  Mitosis Mitosis  Cytokinesis Cytokinesis Cell division Cell division

How do cellsknowwhento divide?Extracellular signals: Steroids, peptides, and proteins that actoverlong or short distances,collectivelyknown as hormones.Cell-bound signals:Such as histocompatibility proteins.Cellsintheimmune system communicate via these signals.(b)StimulatinggrowthfactorReceptor000CellmembraneCytoplasmSignaltransducersTranscriptionfactorProteinthatDNANucleusstimulatescelldivision19-4Fig. 19.11

Copyright © The McGraw-Hill Companies, Inc. Permission required to reproduce or display 19-4  Extracellular signals Extracellular signals: Steroids, peptides, and proteins that act : Steroids, peptides, and proteins that act over long or short distances, over long or short distances, collectively known as hormones. collectively known as hormones.  Cell-bound signals bound signals: Such as : Such as histocompatibility histocompatibility proteins. Cells in proteins. Cells in the immune system communicate via these signals. the immune system communicate via these signals. How do cells know when to divide? How do cells know when to divide? Fig. 19.11

Each signaltransductionpathway/systemhas fourcomponentsThe activation or inhibition of intracellular targets after growthfactor binding is called signal transduction19-5

Copyright © The McGraw-Hill Companies, Inc. Permission required to reproduce or display 19-5 Each signal transduction pathway/system Each signal transduction pathway/system has four components has four components The activation or inhibition of intracellular targets after growth factor binding is called signal transduction

Growth factors-hormones and cell-bound signals thatstimulate orinhibit cellproliferation.2.Receptors-membrane-bound proteins that accept signals3Signal transducers relay messages.Transcription factors activate the expression of genes.(c)InhibitinggrowthfactorReceptorSignaltransducersTranscriptionfactorEProteinthatblocksDNAcell from dividing19-6

Copyright © The McGraw-Hill Companies, Inc. Permission required to reproduce or display 19-6 1. Growth factors Growth factors – hormones and cell hormones and cell-bound signals that bound signals that stimulate or inhibit cell proliferation. stimulate or inhibit cell proliferation. 2. Receptors Receptors – membrane membrane-bound proteins that accept signals. bound proteins that accept signals. 3. Signal transducers Signal transducers relay messages. relay messages. 4. Transcription factors Transcription factors activate the expression of genes. activate the expression of genes

The small GTPaseRASis involved in growthfactorsignaling(d)GrowthfactorReceptorRASRASRAS inactiveRASactiveGDPGTPwhenboundwhenboundtoGDPtoGTPMAPkinasecascade1TranscriptionfactorProliferation19-7Fig.19.12

Copyright © The McGraw-Hill Companies, Inc. Permission required to reproduce or display 19-7 The small The small GTPase RAS is involved in growth factor RAS is involved in growth factor signaling signaling Fig. 19.12

Cell cycle and its regulationDNA synthesisG1G2MDNA segregation19-8

Copyright © The McGraw-Hill Companies, Inc. Permission required to reproduce or display 19-8 Cell cycle and its regulation Cell cycle and its regulation S M DNA synthesis DNA segregation G1 G2

The length of cell cycle varies with each organismMFertilizedXenopusegg0.5hrMG1G224 hrCultured fibroblastMG1G2Saccharomyces cerevisiae2hrSG1G2M2.5 hrSchizosaccharomyces pombe19-9

Copyright © The McGraw-Hill Companies, Inc. Permission required to reproduce or display 19-9 Cultured fibroblast Saccharomyces cerevisiae Schizosaccharomyces pombe Fertilized Xenopus egg 24 hr 2 hr 2.5 hr 0.5 hr G1 G1 G1 S S S S G2 G2 G2 M M M M The length of cell cycle varies with each organism

Experiments with yeast helped identify genesthat control cell divisionThe budding yeastThefission yeastSchizosaccharomyces pombeSaccharomyces cerevisiae19-10

Copyright © The McGraw-Hill Companies, Inc. Permission required to reproduce or display 19-10 Experiments with yeast helped identify genes Experiments with yeast helped identify genes that control cell division that control cell division The budding yeast Saccharomyces cerevisiae The fission yeast Schizosaccharomyces pombe