an introduction to malignant neoplasia from a theoretician ...kuang/class/mmm/lecture1.pdf · an...
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An Introduction to Malignant Neoplasia from a An Introduction to Malignant Neoplasia from a TheoreticianTheoretician’’s Perspectives Perspective
John D. NagyJohn D. NagyDepartment of Life Sciences, Scottsdale Community CollegeDepartment of Life Sciences, Scottsdale Community College
Department of Mathematics and Statistics, Arizona State UniversiDepartment of Mathematics and Statistics, Arizona State Universityty
Mathematical Medicine SeminarMathematical Medicine Seminar
January 16, 2007January 16, 2007
The case history of The case history of ““MaryMary””
1) 42 year1) 42 year--old mother of 3old mother of 3
2) Cigarette smoker since she was 192) Cigarette smoker since she was 19
3) Mary developed a persistent cough some 3) Mary developed a persistent cough some time before presentationtime before presentation
4) In last few days before presentation she had 4) In last few days before presentation she had developed tremors in her hand and other developed tremors in her hand and other neurological symptomsneurological symptoms
Chest XChest X--ray 2 years before ray 2 years before presentationpresentation——film is clear.film is clear.
Not clear at presentation.Not clear at presentation.
Biopsy reveals squamous cell carcinoma of Biopsy reveals squamous cell carcinoma of the lung (a form of lung cancer).the lung (a form of lung cancer).
Squamous cell lung cancer Squamous cell lung cancer –– Gross Gross pathology, unfixedpathology, unfixed
Necrosis in Necrosis in SqCLCSqCLC
Squamous cell lung Squamous cell lung cancer cancer –– Gross Gross
pathology, formalin pathology, formalin fixedfixed
The cause The cause of Maryof Mary’’s s tremorstremors
Invasion and metastasisInvasion and metastasis
From Lynch and From Lynch and MatrisianMatrisian (2002) Differ. 70:561(2002) Differ. 70:561--573.573.
A cancer cell on the moveA cancer cell on the move
““The Hallmarks The Hallmarks of Cancerof Cancer””
From From HanahanHanahan and Weinberg. and Weinberg. (2000) Cell 100:57(2000) Cell 100:57--7070
Red indicates known cancerRed indicates known cancer--associated proteinsassociated proteins
translation="translation="MPPKTPRKTAATAAAAAAEPPAPPPPPPPEEDPEQDSGPEDLPLVRLEFEMPPKTPRKTAATAAAAAAEPPAPPPPPPPEEDPEQDSGPEDLPLVRLEFEETEEPDFTALCQKLKIPDHVRERAWLTWEKVSSVDGVLGGYIQKKKELWGICIFIARVETEEPDFTALCQKLKIPDHVRERAWLTWEKVSSVDGVLGGYIQKKKELWGICIFIARVDLDEMSFTLLSYRKTYEISVHKFFNLLKEIDTSTKVDNAMSRLLKKYDVLFALFSKLEDLDEMSFTLLSYRKTYEISVHKFFNLLKEIDTSTKVDNAMSRLLKKYDVLFALFSKLERTCELIYLTQPSSSISTEINSALVLKVSWITFLLAKGEVLQMEDDLVISFQLMLCVLDRTCELIYLTQPSSSISTEINSALVLKVSWITFLLAKGEVLQMEDDLVISFQLMLCVLDYFIKLSPPMLLKEPYKTAVIPINGSPRTPRRGQNRSARIAKQLENDTRIIEVLCKEHEYFIKLSPPMLLKEPYKTAVIPINGSPRTPRRGQNRSARIAKQLENDTRIIEVLCKEHECNIDEVKNVYFKNFIPFMNSLGLVTSNGLPEVENLSKRYEEIYLKNKDLDRRLFLDHDCNIDEVKNVYFKNFIPFMNSLGLVTSNGLPEVENLSKRYEEIYLKNKDLDRRLFLDHDKTLQTDSIDSFETQRTPRKSNLDEEVNIIPPHTPVRTVMNTIQQLMMILNSASDQPSEKTLQTDSIDSFETQRTPRKSNLDEEVNIIPPHTPVRTVMNTIQQLMMILNSASDQPSENLISYFNNCTVNPKESILKRVKDIGYIFKEKFAKAVGQGCVEIGSQRYKLGVRLYYRVNLISYFNNCTVNPKESILKRVKDIGYIFKEKFAKAVGQGCVEIGSQRYKLGVRLYYRVMESMLKSEEERLSIQNFSKLLNDNIFHMSLLACALEVVMATYSRSTSQNLDSGTDLSFMESMLKSEEERLSIQNFSKLLNDNIFHMSLLACALEVVMATYSRSTSQNLDSGTDLSFPWILNVLNLKAFDFYKVIESFIKAEGNLTREMIKHLERCEHRIMESLAWLSDSPLFDLPWILNVLNLKAFDFYKVIESFIKAEGNLTREMIKHLERCEHRIMESLAWLSDSPLFDLIKQSKDREGPTDHLESACPLNLPLQNNHTAADMYLSPVRSPKKKGSTTRVNSTANAETIKQSKDREGPTDHLESACPLNLPLQNNHTAADMYLSPVRSPKKKGSTTRVNSTANAETQATSAFQTQKPLKSTSLSLFYKKVYRLAYLRLNTLCERLLSEHPELEHIIWTLFQHTLQATSAFQTQKPLKSTSLSLFYKKVYRLAYLRLNTLCERLLSEHPELEHIIWTLFQHTLQNEYELMRDRHLDQIMMCSMYGICKVKNIDLKFKIIVTAYKDLPHAVQETFKRVLIKEQNEYELMRDRHLDQIMMCSMYGICKVKNIDLKFKIIVTAYKDLPHAVQETFKRVLIKEEEYDSIIVFYNSVFMQRLKTNILQYASTRPPTLSPIPHIPRSPYKFPSSPLRIPGGNIEEYDSIIVFYNSVFMQRLKTNILQYASTRPPTLSPIPHIPRSPYKFPSSPLRIPGGNIYISPLKSPYKISEGLPTPTKMTPRSRILVSIGESFGTSEKFQKINQMVCNSDRVLKRSYISPLKSPYKISEGLPTPTKMTPRSRILVSIGESFGTSEKFQKINQMVCNSDRVLKRSAEGSNPPKPLKKLRFDIEGSDEADGSKHLPGESKFQQKLAEMTSTRTRMQKQKMNDSMAEGSNPPKPLKKLRFDIEGSDEADGSKHLPGESKFQQKLAEMTSTRTRMQKQKMNDSMDTSNKEEKDTSNKEEK""
Structure of normal pRBStructure of normal pRB
translation="translation="MPPKTPRKTAATAAAAAAEPPAPPPPPPPEEDPEQDSGPEDLPLVRLEFEMPPKTPRKTAATAAAAAAEPPAPPPPPPPEEDPEQDSGPEDLPLVRLEFEETEEPDFTALCQKLKIPDHVRERAWLTWEKVSSVDGVLGGYIQKKKELWGICIFIARVETEEPDFTALCQKLKIPDHVRERAWLTWEKVSSVDGVLGGYIQKKKELWGICIFIARVDLDEMSFTLLSYRKTYEISVHKFFNLLKEIDTSTKVDNAMSRLLKKYDVLFALFSKLEDLDEMSFTLLSYRKTYEISVHKFFNLLKEIDTSTKVDNAMSRLLKKYDVLFALFSKLERTCELIYLTQPSSSISTEINSALVLKVSWITFLLAKGEVLQMEDDLVISFQLMLCVLDRTCELIYLTQPSSSISTEINSALVLKVSWITFLLAKGEVLQMEDDLVISFQLMLCVLDYFIKLSPPMLLKEPYKTAVIPINGSPRTPRRGQNRSARIAKQLENDTRIIEVLCKEHEYFIKLSPPMLLKEPYKTAVIPINGSPRTPRRGQNRSARIAKQLENDTRIIEVLCKEHECNIDEVKNVYFKNFIPFMNSLGLVTSNGLPEVENLSKRYEEIYLKNKDLDRRLFLDHDCNIDEVKNVYFKNFIPFMNSLGLVTSNGLPEVENLSKRYEEIYLKNKDLDRRLFLDHDKTLQTDSIDSFETQRTPRKSNLDEEVNIIPPHTPVRTVMNTIQQLMMILNSASDQPSEKTLQTDSIDSFETQRTPRKSNLDEEVNIIPPHTPVRTVMNTIQQLMMILNSASDQPSENLISYFNNCTVNPKESILKRVKDIGYIFKEKFAKAVGQGCVEIGSQRYKLGVRLYYRVNLISYFNNCTVNPKESILKRVKDIGYIFKEKFAKAVGQGCVEIGSQRYKLGVRLYYRVMESMLKSEEERLSIQNFSKLLNDNIFHMSLLACALEVVMATYSRSTSQNLDSGTDLSFMESMLKSEEERLSIQNFSKLLNDNIFHMSLLACALEVVMATYSRSTSQNLDSGTDLSFPWILNVLNLKAFDFYKVIESFIKAEGNLTREMIKHLERCEHRIMESLAWLSDSPLFDLPWILNVLNLKAFDFYKVIESFIKAEGNLTREMIKHLERCEHRIMESLAWLSDSPLFDLIKQSKDREGPTDHLESACPLNLPLQNNHTAADMYLSPVRSPKKKGSTTRVNSTANAETIKQSKDREGPTDHLESACPLNLPLQNNHTAADMYLSPVRSPKKKGSTTRVNSTANAETQATSAFQTQKPLKSTSLSLFYKKVYRLAYLRLNTLCERLLSEHPELEHIIWTLFQHTLQATSAFQTQKPLKSTSLSLFYKKVYRLAYLRLNTLCERLLSEHPELEHIIWTLFQHTLQNEYELMRDRHLDQIMMCSMYGICKVKNIDLKFKIIVTAYKDLPHAVQETFKRVLIKEQNEYELMRDRHLDQIMMCSMYGICKVKNIDLKFKIIVTAYKDLPHAVQETFKRVLIKEEEYDSIIVFYNSVFMQRLKTNILQYASTRPPTLSPIPHIPRSPYKFPSSPLRIPGGNIEEYDSIIVFYNSVFMQRLKTNILQYASTRPPTLSPIPHIPRSPYKFPSSPLRIPGGNIYISPLKSPYKISEGLPTPTKMTPRSRILVSIGESYISPLKSPYKISEGLPTPTKMTPRSRILVSIGESFGTSEKFQKINQMVCNSDRVLKRSFGTSEKFQKINQMVCNSDRVLKRSAEGSNPPKPLKKLRFDIEGSDEADGSKHLPGESKFQQKLAEMTSTRTRMQKQKMNDSMAEGSNPPKPLKKLRFDIEGSDEADGSKHLPGESKFQQKLAEMTSTRTRMQKQKMNDSMDTSNKEEKDTSNKEEK""
pRB in MarypRB in Mary’’s lung cancer cellss lung cancer cells
pRB in MarypRB in Mary’’s cancer cells is always inactivateds cancer cells is always inactivated
Where does pRB come from?Where does pRB come from?
1 1 ttccggttttttccggtttt tctcaggggatctcagggga cgttgaaattcgttgaaatt atttttgtaaatttttgtaa cgggagtcggcgggagtcgg gagaggacgggagaggacgg
61 61 ggcgtgccccggcgtgcccc gcgtgcgcgcgcgtgcgcgc gcgtcgtcctgcgtcgtcct ccccggcgctccccggcgct cctccacagccctccacagc tcgctggctctcgctggctc
121 121 ccgccgcggaccgccgcgga aaggcgtcataaggcgtcat gccgcccaaagccgcccaaa accccccgaaaccccccgaa aaacggccgcaaacggccgc caccgccgcccaccgccgcc
181 181 gctgccgccggctgccgccg cggaaccccccggaaccccc ggcaccgccgggcaccgccg ccgccgccccccgccgcccc ctcctgaggactcctgagga ggacccagagggacccagag
241 241 caggacagcgcaggacagcg gcccggaggagcccggagga cctgcctctccctgcctctc gtcaggcttggtcaggcttg agtttgaagaagtttgaaga aacagaagaaaacagaagaa
301 301 cctgattttacctgatttta ctgcattatgctgcattatg tcagaaattatcagaaatta aagataccagaagataccag atcatgtcagatcatgtcag agagagagctagagagagct
361 361 tggttaactttggttaactt gggagaaagtgggagaaagt ttcatctgtgttcatctgtg gatggagtatgatggagtat tgggaggttatgggaggtta tattcaaaagtattcaaaag
421 421 aaaaaggaacaaaaaggaac tgtggggaattgtggggaat ctgtatctttctgtatcttt attgcacgagattgcacgag ttgacctagattgacctaga tgagatgtcgtgagatgtcg
481 481 ttcactttacttcactttac tgagctacagtgagctacag aaaaacatacaaaaacatac gaaatcagtggaaatcagtg tccataaatttccataaatt ctttaacttactttaactta
541 541 ctaaaagaaactaaaagaaa ttgataccagttgataccag taccaaagtttaccaaagtt gataatgctagataatgcta tgtcaagacttgtcaagact gttgaagaaggttgaagaag
601 601 tatgatgtattatgatgtat tgtttgcacttgtttgcact cttcagcaaacttcagcaaa ttggaaaggattggaaagga catgtgaactcatgtgaact tatatatttgtatatatttg
661 661 acacaacccaacacaaccca gcagttcgatgcagttcgat atctactgaaatctactgaa ataaattctgataaattctg cattggtgctcattggtgct aaaagtttctaaaagtttct
721 721 tggatcacattggatcacat ttttattagcttttattagc taaaggggaataaaggggaa gtattacaaagtattacaaa tggaagatgatggaagatga tctggtgatttctggtgatt
781 781 tcatttcagttcatttcagt taatgctatgtaatgctatg tgtccttgactgtccttgac tattttattatattttatta aactctcaccaactctcacc tcccatgttgtcccatgttg
841 841 ctcaaagaacctcaaagaac catataaaaccatataaaac agctgttataagctgttata cccattaatgcccattaatg gttcacctcggttcacctcg aacacccaggaacacccagg
Structure of pRB geneStructure of pRB gene
901 901 cgaggtcagacgaggtcaga acaggagtgcacaggagtgc acggatagcaacggatagca aaacaactagaaacaactag aaaatgatacaaaatgatac aagaattattaagaattatt
961 961 gaagttctctgaagttctct gtaaagaacagtaaagaaca tgaatgtaattgaatgtaat atagatgaggatagatgagg tgaaaaatgttgaaaaatgt ttatttcaaattatttcaaa
1021 1021 aattttatacaattttatac cttttatgaacttttatgaa ttctcttggattctcttgga cttgtaacatcttgtaacat ctaatggactctaatggact tccagaggtttccagaggtt
1081 1081 gaaaatctttgaaaatcttt ctaaacgatactaaacgata cgaagaaattcgaagaaatt tatcttaaaatatcttaaaa ataaagatctataaagatct agatcgaagaagatcgaaga
1141 1141 ttatttttggttatttttgg atcatgataaatcatgataa aactcttcagaactcttcag actgattctaactgattcta tagacagttttagacagttt tgaaacacagtgaaacacag
1201 1201 agaacaccacagaacaccac gaaaaagtaagaaaaagtaa ccttgatgaaccttgatgaa gaggtgaatagaggtgaata taattcctcctaattcctcc acacactccaacacactcca
1261 1261 gttaggactggttaggactg ttatgaacacttatgaacac tatccaacaatatccaacaa ttaatgatgattaatgatga ttttaaattcttttaaattc tgcaagtgattgcaagtgat
1321 1321 caaccttcagcaaccttcag aaaatctgataaaatctgat ttcctattttttcctatttt aacaactgcaaacaactgca cagtgaatcccagtgaatcc aaaagaaagtaaaagaaagt
1381 1381 atactgaaaaatactgaaaa gagtgaaggagagtgaagga tataggatactataggatac atctttaaagatctttaaag agaaatttgcagaaatttgc taaagctgtgtaaagctgtg
1441 1441 ggacagggttggacagggtt gtgtcgaaatgtgtcgaaat tggatcacagtggatcacag cgatacaaaccgatacaaac ttggagttcgttggagttcg cttgtattaccttgtattac
1501 1501 cgagtaatggcgagtaatgg aatccatgctaatccatgct taaatcagaataaatcagaa gaagaacgatgaagaacgat tatccattcatatccattca aaattttagcaaattttagc
1561 1561 aaacttctgaaaacttctga atgacaacatatgacaacat ttttcatatgttttcatatg tctttattggtctttattgg cgtgcgctctcgtgcgctct tgaggttgtatgaggttgta
1621 1621 atggccacatatggccacat atagcagaagatagcagaag tacatctcagtacatctcag aatcttgattaatcttgatt ctggaacagactggaacaga tttgtctttctttgtctttc
1681 1681 ccatggattcccatggattc tgaatgtgcttgaatgtgct taatttaaaataatttaaaa gcctttgattgcctttgatt tttacaaagttttacaaagt gatcgaaagtgatcgaaagt
1741 1741 tttatcaaagtttatcaaag cagaaggcaacagaaggcaa cttgacaagacttgacaaga gaaatgataagaaatgataa aacatttagaaacatttaga acgatgtgaaacgatgtgaa
Structure of pRB geneStructure of pRB gene
1801 1801 catcgaatcacatcgaatca tggaatcccttggaatccct tgcatggctctgcatggctc tcagattcactcagattcac ctttatttgactttatttga tcttattaaatcttattaaa
1861 1861 caatcaaaggcaatcaaagg accgagaaggaccgagaagg accaactgataccaactgat caccttgaatcaccttgaat ctgcttgtccctgcttgtcc tcttaatctttcttaatctt
1921 1921 cctctccagacctctccaga ataatcacacataatcacac tgcagcagattgcagcagat atgtatctttatgtatcttt ctcctgtaagctcctgtaag atctccaaagatctccaaag
1981 1981 aaaaaaggttaaaaaaggtt caactacgcgcaactacgcg tgtaaattcttgtaaattct actgcaaatgactgcaaatg cagagacacacagagacaca agcaacctcaagcaacctca
2041 2041 gccttccagagccttccaga cccagaagcccccagaagcc attgaaatctattgaaatct acctctctttacctctcttt cactgttttacactgtttta taaaaaagtgtaaaaaagtg
2101 2101 tatcggctagtatcggctag cctatctccgcctatctccg gctaaatacagctaaataca ctttgtgaacctttgtgaac gccttctgtcgccttctgtc tgagcacccatgagcaccca
2161 2161 gaattagaacgaattagaac atatcatctgatatcatctg gacccttttcgacccttttc cagcacaccccagcacaccc tgcagaatgatgcagaatga gtatgaactcgtatgaactc
2221 2221 atgagagacaatgagagaca ggcatttggaggcatttgga ccaaattatgccaaattatg atgtgttccaatgtgttcca tgtatggcattgtatggcat atgcaaagtgatgcaaagtg
2281 2281 aagaatatagaagaatatag accttaaattaccttaaatt caaaatcattcaaaatcatt gtaacagcatgtaacagcat acaaggatctacaaggatct tcctcatgcttcctcatgct
2341 2341 gttcaggagagttcaggaga cattcaaacgcattcaaacg tgttttgatctgttttgatc aaagaagaggaaagaagagg agtatgattcagtatgattc tattatagtatattatagta
2401 2401 ttctataactttctataact cggtcttcatcggtcttcat gcagagactggcagagactg aaaacaaataaaaacaaata ttttgcagtattttgcagta tgcttccacctgcttccacc
2461 2461 aggccccctaaggcccccta ccttgtcaccccttgtcacc aatacctcacaatacctcac attcctcgaaattcctcgaa gcccttacaagcccttacaa gtttcctagtgtttcctagt
2521 2521 tcacccttactcacccttac ggattcctggggattcctgg agggaacatcagggaacatc tatatttcactatatttcac ccctgaagagccctgaagag tccatataaatccatataaa
2581 2581 atttcagaagatttcagaag gtctgccaacgtctgccaac accaacaaaaaccaacaaaa atgactccaaatgactccaa gatcaagaatgatcaagaat cttagtatcacttagtatca
2641 2641 attggtgaatattggtgaat cattcgggaccattcgggac ttctgagaagttctgagaag ttccagaaaattccagaaaa taaatcagattaaatcagat ggtatgtaacggtatgtaac
Structure of pRB geneStructure of pRB gene
2701 2701 agcgaccgtgagcgaccgtg tgctcaaaagtgctcaaaag aagtgctgaaaagtgctgaa ggaagcaaccggaagcaacc ctcctaaaccctcctaaacc actgaaaaaaactgaaaaaa
2761 2761 ctacgctttgctacgctttg atattgaaggatattgaagg atcagatgaaatcagatgaa gcagatggaagcagatggaa gtaaacatctgtaaacatct cccaggagagcccaggagag
2821 2821 tccaaatttctccaaatttc agcagaaactagcagaaact ggcagaaatgggcagaaatg acttctactcacttctactc gaacacgaatgaacacgaat gcaaaagcaggcaaaagcag
2881 2881 aaaatgaatgaaaatgaatg atagcatggaatagcatgga tacctcaaactacctcaaac aaggaagagaaaggaagaga aatgaggatcaatgaggatc tcaggacctttcaggacctt
2941 2941 ggtggacactggtggacact gtgtacacctgtgtacacct ctggattcatctggattcat tgtctctcactgtctctcac agatgtgactagatgtgact gtataactttgtataacttt
3001 3001 cccaggttctcccaggttct gtttatggccgtttatggcc acatttaataacatttaata tcttcagctctcttcagctc tttttgtggatttttgtgga tataaaatgttataaaatgt
3061 3061 gcagatgcaagcagatgcaa ttgtttgggtttgtttgggt gagtcctaaggagtcctaag ccacttgaaaccacttgaaa tgttagtcattgttagtcat tgttatttattgttatttat
3121 3121 acaagattgaacaagattga aaatcttgtgaaatcttgtg taaatcctgctaaatcctgc catttaaaaacatttaaaaa gttgtagcaggttgtagcag attgtttcctattgtttcct
3181 3181 cttccaaagtcttccaaagt aaaattgctgaaaattgctg tgctttatggtgctttatgg atagtaagaaatagtaagaa tggccctagatggccctaga gtgggagtccgtgggagtcc
3241 3241 tgataacccatgataaccca ggcctgtctgggcctgtctg actactttgcactactttgc cttcttttgtcttcttttgt agcatataggagcatatagg tgatgtttgctgatgtttgc
3301 3301 tcttgttttttcttgttttt attaatttatattaatttat atgtatatttatgtatattt ttttaatttattttaattta acatgaacacacatgaacac ccttagaaaaccttagaaaa
3361 3361 tgtgtcctattgtgtcctat ctatcttccactatcttcca aatgcaatttaatgcaattt gattgactgcgattgactgc ccattcaccaccattcacca aaattatcctaaattatcct
3421 3421 gaactcttctgaactcttct gcaaaaatgggcaaaaatgg atattattagatattattag aaattagaaaaaattagaaa aaaattactaaaaattacta attttacacaattttacaca
3481 3481 ttagattttattagatttta ttttactattttttactatt ggaatctgatggaatctgat atactgtgtgatactgtgtg cttgttttatcttgttttat aaaattttgcaaaattttgc
3541 3541 ttttaattaattttaattaa ataaaagctgataaaagctg gaagcaaagtgaagcaaagt ataaccatatataaccatat gatactatcagatactatca tactactgaatactactgaa
Structure of pRB geneStructure of pRB gene
3601 3601 acagatttcaacagatttca tacctcagaatacctcagaa tgtaaaagaatgtaaaagaa cttactgattcttactgatt attttcttcaattttcttca tccaacttattccaacttat
3661 3661 gtttttaaatgtttttaaat gaggattattgaggattatt gatagtactcgatagtactc ttggtttttattggttttta taccattcagtaccattcag atcactgaatatcactgaat
3721 3721 ttataaagtattataaagta cccatctagtcccatctagt acttgaaaaaacttgaaaaa gtaaagtgttgtaaagtgtt ctgccagatcctgccagatc ttaggtatagttaggtatag
3781 3781 aggaccctaaaggaccctaa cacagtatatcacagtatat cccaagtgcacccaagtgca ctttctaatgctttctaatg tttctgggtctttctgggtc ctgaagaattctgaagaatt
3841 3841 aagatacaaaaagatacaaa ttaattttacttaattttac tccataaacatccataaaca gactgttaatgactgttaat tataggagcctataggagcc ttaattttttttaatttttt
3901 3901 tttcatagagtttcatagag atttgtctaaatttgtctaa ttgcatctcattgcatctca aaattattctaaattattct gccctccttagccctcctta atttgggaagatttgggaag
3961 3961 gtttgtgtttgtttgtgttt tctctggaattctctggaat ggtacatgtcggtacatgtc ttccatgtatttccatgtat cttttgaactcttttgaact ggcaattgtcggcaattgtc
4021 4021 tatttatctttatttatctt ttatttttttttattttttt aagtcagtataagtcagtat ggtctaacacggtctaacac tggcatgttctggcatgttc aaagccacataaagccacat
4081 4081 tatttctagttatttctagt ccaaaattacccaaaattac aagtaatcaaaagtaatcaa gggtcattatgggtcattat gggttaggcagggttaggca ttaatgtttcttaatgtttc
4141 4141 tatctgattttatctgattt tgtgcaaaagtgtgcaaaag cttcaaattacttcaaatta aaacagctgcaaacagctgc attagaaaaaattagaaaaa gaggcgcttcgaggcgcttc
4201 4201 tcccctcccctcccctcccc tacacctaaatacacctaaa ggtgtatttaggtgtattta aactatcttgaactatcttg tgtgattaactgtgattaac ttatttagagttatttagag
4261 4261 atgctgtaacatgctgtaac ttaaaataggttaaaatagg ggatatttaaggatatttaa ggtagcttcaggtagcttca gctagcttttgctagctttt aggaaaatcaaggaaaatca
4321 4321 ctttgtctaactttgtctaa ctcagaattactcagaatta tttttaaaaatttttaaaaa gaaatctggtgaaatctggt cttgttagaacttgttagaa aacaaaatttaacaaaattt
4381 4381 tattttgtgctattttgtgc tcatttaagttcatttaagt ttcaaacttattcaaactta ctattttgacctattttgac agttattttgagttattttg ataacaatgaataacaatga
4441 4441 cactagaaaacactagaaaa cttgactccacttgactcca tttcatcatttttcatcatt gtttctgcatgtttctgcat gaatatcatagaatatcata caaatcagttcaaatcagtt
Structure of pRB geneStructure of pRB gene
4501 4501 agtttttaggagtttttagg tcaagggctttcaagggctt actatttctgactatttctg ggtcttttgcggtcttttgc tactaagttctactaagttc acattagaatacattagaat
4561 4561 tagtgccagatagtgccaga attttaggaaattttaggaa cttcagagatcttcagagat cgtgtattgacgtgtattga gatttcttaagatttcttaa ataatgcttcataatgcttc
4621 4621 agatattattagatattatt gctttattgcgctttattgc ttttttgtatttttttgtat tggttaaaactggttaaaac tgtacatttatgtacattta aaattgctataaattgctat
4681 4681 gttactatttgttactattt tctacaattatctacaatta atagtttgtcatagtttgtc tattttaaaatattttaaaa taaattagtttaaattagtt gttaagagtcgttaagagtc
Structure of pRB geneStructure of pRB gene
1801 1801 catcgaatcacatcgaatca tggaatcccttggaatccct tgcatggctctgcatggctc tcagattcactcagattcac ctttatttgactttatttga tcttattaaatcttattaaa
1861 1861 caatcaaaggcaatcaaagg accgagaaggaccgagaagg accaactgataccaactgat caccttgaatcaccttgaat ctgcttgtccctgcttgtcc tcttaatctttcttaatctt
1921 1921 cctctccagacctctccaga ataatcacacataatcacac tgcagcagattgcagcagat atgtatctttatgtatcttt ctcctgtaagctcctgtaag atctccaaagatctccaaag
1981 1981 aaaaaaggttaaaaaaggtt caactacgcgcaactacgcg tgtaaattcttgtaaattct actgcaaatgactgcaaatg cagagacacacagagacaca agcaacctcaagcaacctca
2041 2041 gccttccagagccttccaga cccagaagcccccagaagcc attgaaatctattgaaatct acctctctttacctctcttt cactgttttacactgtttta taaaaaagtgtaaaaaagtg
2101 2101 tatcggctagtatcggctag cctatctccgcctatctccg gctaaatacagctaaataca ctttgtgaacctttgtgaac gccttctgtcgccttctgtc tgagcacccatgagcaccca
2161 2161 gaattagaacgaattagaac atatcatctgatatcatctg gacccttttcgacccttttc cagcacaccccagcacaccc tgcagaatgatgcagaatga gtatgaactcgtatgaactc
2221 2221 atgagagacaatgagagaca ggcatttggaggcatttgga ccaaattatgccaaattatg atgtgttccaatgtgttcca tgtatggcattgtatggcat atgcaaagtgatgcaaagtg
2281 2281 aagaatatagaagaatatag accttaaattaccttaaatt caaaatcattcaaaatcatt gtaacagcatgtaacagcat acaaggatctacaaggatct tcctcatgcttcctcatgct
2341 2341 gttcaggagagttcaggaga cattcaaacgcattcaaacg tgttttgatctgttttgatc aaagaagaggaaagaagagg agtatgattcagtatgattc tattatagtatattatagta
2401 2401 ttctataactttctataact cggtcttcatcggtcttcat gcagagactggcagagactg aaaacaaataaaaacaaata ttttgcagtattttgcagta tgcttccacctgcttccacc
2461 2461 aggccccctaaggcccccta ccttgtcaccccttgtcacc aatacctcacaatacctcac attcctcgaaattcctcgaa gcccttacaagcccttacaa gtttcctagtgtttcctagt
2521 2521 tcacccttactcacccttac ggattcctggggattcctgg agggaacatcagggaacatc tatatttcactatatttcac ccctgaagagccctgaagag tccatataaatccatataaa
2581 2581 atttcagaagatttcagaag gtctgccaacgtctgccaac accaacaaaaaccaacaaaa atgactccaaatgactccaa gatcaagaatgatcaagaat cttagtatcacttagtatca
2641 2641 attggtgaatattggtgaat cattcgcattcg gacgac ttctgagaagttctgagaag ttccagaaaattccagaaaa taaatcagattaaatcagat ggtatgtaacggtatgtaac
Structure of MaryStructure of Mary’’s cancer pRB genes cancer pRB gene
What went wrong in MaryWhat went wrong in Mary’’s cells?s cells?
Is Is pRBpRB mutation a sufficient explanation of the mutation a sufficient explanation of the etiology of squamous cell lung cancer?etiology of squamous cell lung cancer?
One can attack this question with a very simple Markov chainOne can attack this question with a very simple Markov chain
1) Assume the number of cells in an organ is fixed at 1) Assume the number of cells in an organ is fixed at NN..
2) At every time step, exactly one cell dies and one cell reprod2) At every time step, exactly one cell dies and one cell reproduces; uces; therefore, tissue homeostasis is preserved (therefore, tissue homeostasis is preserved (notnot a feature of cancer).a feature of cancer).
Healthy LungHealthy Lung SCLC, equivalent scaleSCLC, equivalent scale
Source: Source: fybio.bio.usyd.edu.aufybio.bio.usyd.edu.au Source: Nagy, 2005. MBE 2: 381Source: Nagy, 2005. MBE 2: 381--418.418.
Is Is pRBpRB mutation a sufficient explanation of the mutation a sufficient explanation of the etiology of squamous cell lung cancer?etiology of squamous cell lung cancer?
One can attack this question with a very simple Markov chainOne can attack this question with a very simple Markov chain
3) Every cell exists in one of two states3) Every cell exists in one of two states——healthy or malignant.healthy or malignant.
4) Whenever a healthy cell reproduces, it 4) Whenever a healthy cell reproduces, it breeds truebreeds true with with constantconstantprobability 1 probability 1 –– uu, , or it or it ““mutatesmutates”” into a malignant cell into a malignant cell with probability with probability uu..
5) Reproduction is biased, usually in favor of malignant cells. 5) Reproduction is biased, usually in favor of malignant cells. The The measure of this bias is measure of this bias is rr. When . When rr > 1, selection favors malignancy.> 1, selection favors malignancy.
7) Probability of mortality is uniformly distributed across all 7) Probability of mortality is uniformly distributed across all existing existing cells, and is independent of reproduction.cells, and is independent of reproduction.
Is Is pRBpRB mutation a sufficient explanation of the mutation a sufficient explanation of the etiology of squamous cell lung cancer?etiology of squamous cell lung cancer?
One can attack this question with a very simple Markov chainOne can attack this question with a very simple Markov chain
Let Let aa and and b b be the number of healthy and malignant cells, respectively; be the number of healthy and malignant cells, respectively; a + b = Na + b = N. .
The reproduction probabilities are:The reproduction probabilities are:
Healthy cell reproduces, Healthy cell reproduces, breeds truebreeds true
Mortality probabilities for healthy and malignant cells are Mortality probabilities for healthy and malignant cells are a/Na/N and and b/Nb/N, , respectively.respectively.
(1 )u aa rb
−+
ba rb+
uaa rb+
Healthy cell Healthy cell reproduces, mutatesreproduces, mutates
Malignant cell Malignant cell reproducesreproduces
The transition matrix for this processThe transition matrix for this process
Let Let P(i,jP(i,j)) be the probability of transitioning from state be the probability of transitioning from state b = ib = i to to b = jb = j. . ThenThen
( ), 1,
(1 )( ), 1,( , )
1 ( , 1) ( , 1), ,0, elsewhere,
i
i
u N i ri N ij i
A N
u N i ij iP i j
A NP i i P i i j i
− + − = +
− −= −=
− − − + =
for 0 , , and .ii j N A N i ri≤ ≤ = − −
Immediate ResultImmediate Result
{ | 0} (0, )ST S TP b j b P j+ = = =
From a well known result of the theory of Markov chains, at timeFrom a well known result of the theory of Markov chains, at time steps steps TT, , S S > 0 and for > 0 and for jj > 0, > 0,
0 1 2 N......
⇒ If a cohort is large during a period of study of length If a cohort is large during a period of study of length SS, cancer , cancer risk*risk* in the cohort will be essentially constant regardless of the agin the cohort will be essentially constant regardless of the age e of the cohort.of the cohort.
{ | 0} depends on , not T S TP b j b S T+ = =
Epidemiological risk = Epidemiological risk = ““proportion of persons unaffected at the beginning of a study perproportion of persons unaffected at the beginning of a study period who iod who [get cancer] during the study period.[get cancer] during the study period.”” ((JekelJekel et al., 1996)et al., 1996)
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
20 30 40 50 60 70 80
Age (Years)
Can
cer
Ris
k (%
)
Lung Cancer
Breast Cancer
Typical Risk Curves Contradict the Previous ResultTypical Risk Curves Contradict the Previous Result
1010--year ageyear age--dependent risk of lung cancerdependent risk of lung cancerSource: Center for Disease Control and Prevention Source: Center for Disease Control and Prevention www.cdc.gov/cancer/lung/statistics/risk_age.htmwww.cdc.gov/cancer/lung/statistics/risk_age.htm
Observations like this Observations like this are responsible for the are responsible for the
acceptance of the multiacceptance of the multi--hit theory of cancer hit theory of cancer
etiologyetiology
0 1 2 N......A Second Immediate ResultA Second Immediate Result
( , ) 1 is absorbing.P N N b N= ⇔ =
For ( , ) 1 All other states are transient
i NP i i
≠< ⇒
⇒ Eventually all cells will become malignant (almost always) Eventually all cells will become malignant (almost always)
3) Number of states is finite3) Number of states is finite
2)2)
1)1)