Markus M. Lerch Department of Gastroenterology, Endocrinology and Nutrition

Ernst-Moritz-Arndt-University, Greifswald

Genetics of chronicpancreatitis and pancreatic

cancer1456 1856

Medizinische Klinik der königlichen Universität Greifswald

Chronic Pancreatitis - Etiology

Alcohol Idiopathic Metabolic Anatomical Hereditary Autoimmune (?)

Hereditary Pancreatitis

14 year old girl with chronic pancreatitis and R122H-mutation

48 year old women with chronic pancreatitisand R122H-mutation

Hereditary pancreatitis is clinically indistinguishable fromother forms and varities of pancreatitis.

Identification of the pancreatitis gene

DNA

1. Family 2. Genetic Mapping

Chromosom 7

HereditaryPancreatitisgene

ccaccaccagtcaggcacactctaccaccATGAATCCACTCCTGATCCTTACCTTTGTGG/ACAGCTGCTCgtgagtatcatgccctgcctcaggccccaaccacccccccgttcctggccga

3. Mutation

Point Mutation in the Trypsino-gen GeneRecruitment

4. Mechanism

Functional Meaning?

Trypsinogen

Whitcomb et al. Nature Genetics 1996

P. Simon, F.U. Weiss et al. J Biol Chem. 2002;277:5404-10

Diagnosis and Screening for Hereditary Pancreatitis

A C G C C N G C G T G T

C T

Sequence in Exon 3Arg

RSS1 wt AAC-GCC-CGC-GTG-T

CysR-122-C AAC-GCC-TGC-GTG-T

Afl III BstU I

Wild

type

Wild

type

R122H

R122H

R122C

R122C

Contro

l

Contro

l

Today, restriction enzymedigest with BstU I representsthe most extensive initial screening test for hereditarypancreatitis.

D22G

K23R

R116C

K92N

E79K

G83E

R122H/C

V123M

P36R

N29I/T

D100H

L104PC139F

Activation site

Cationic trypsin

1952: Comfort and Steinberg reported for the first time an autosomal dominant trait fora family with chronicpancreatitis.

Hereditary Pancreatitis in Germany

1985: the first germanfamily was reported

1996: Whitcomb et al. discoveredthe first mutation associated withchronic hereditary pancreatitis in the cationic trypsinogen gene(PRSS1).

GreifswaldGreifswald

Sporadic point mutations in the PRSS1- Gen in idiopathicchronic Pancreatitis

In 5 of 50 Patients with idiopathic Pancreatitis (10%) mutations inthe cationic Trypsinogen gene were found.

10%

90%

35%

65%

Affected Patients represented 35%of all patients under 25 years. Simon P, Weiss F.U. et al JAMA. 2002;288:2122

50-70% increased riskfor pancreatic cancer in patients with hereditary pancreatitis. 40% cumulative risk until age of 70 years.

Eliminationt/Treatmentof causal factors:Smoking, AlcoholHyperlipidemia, Hypercalcemia,Gallstones, Duct stricture,Drugs and Medications age, years

0

10

20

30

40

50

60

0 20 40 60

cumulative pancreaticcancer risk, %

age

at d

iagn

osis

of p

ancr

eatic

canc

er 80

70

60

50

40

30

20Non-smokers smokers

p < 0.01

Pancreatic Cancer in Hereditary Pancreatitis

Howes N, Lerch MM et al Clinical Gastroenterology and Hepatology 2004; 2: 252-261;Lowenfels AB, JAMA 2001; 286: 169-170.

Pancreatic secretory Trypsin Inhibitor (PSTI, SPINK-1)

Model by A. Model by A. BrunskilBrunskil & W. F. & W. F. FureyFurey

Witt et al, (Nat. Genet., 2000)Mutations in 23% of children with idiopathic chronic Pancreatitis

autosomal-recessive disorder

Pfützer et al, (Gastroenterology, 2000)Mutations in idiopathic chronic Pancreatitis (25%), hereditary Pancreatitis and inthe healthy population (2%).

Modifier - Gene, risk of pancreatitis < 1%

Bhatia et al, Schneider et al, (Gastroenterology, 2002)Mutations in tropical calcifying pancreatitis (up to 44%) and in ‘Fibrocalculous PancreaticDiabetes mellitus‘ (55%).

Risk factor for tropical Pancreatitis andDiabetes mellitus

SPINK1-Mutations in Patients with Hereditary PancreatitisSymbols

Empty symbol

chronic Pancreatitis

positiv for PRSS1 Mutation

positiv for N34S Mutation

Asymptomatic carrier

wt

IV:18

IV:25

I:154

I:281

II:164

II:361

II:560

III:2 36

II:2 II:469

II:7 50

III:516

II:668

III:613

II:846

III:335

III:1 III:4

I:1 I:287

II:259

II:359

II:462

III:432

II:150

III:128

III:226

III:330

I:245

II:1

I:145

SPINK1 Mutations (N34S) are found amongPancreatitis patients as well as among healthy carriersof Trypsinogen mutations.

Weiss F.U. J. Med. Gen. 2003

I.

II.III.

SPINK1 Mutations in Hereditary PancreatitisP

heno

type

, % o

f tot

al

Cumulative Incidence of Pancreatitis

Age at disease onset, years0 10 20 30 40 50 60

0

20

40

60

80

100

PRSS1, SPINK wt

PRSS1, SPINK N34S

0 10 20 30 40 50 60

20

40

60

80

100

mild Pancreatitis

severePancreatitis

0 10 20 30 40 50 600

20

40

60

80

100

No Diabetes

Diabetes

SPINK1 Mutations have no influence on the severity or clinical disease courseof hereditary pancreatitis Weiss F.U. et al. J. Med. Gen.

Chronic Pancreatitis with CFTR Mutations

Kerem et al. Science 1989; 245: 1073-80

ΔF 508 Mutation

One third of patients (n=27) with idiopathic pancreatitiscarry CFTR-Mutations (Risk x 80). J. Cohn et al. New Engl J Med 1998;339:653-58

CFTR Mutations represent a risk factor for chronic pancreatitis in patients without a history of alcohol abuse (19% of n = 60), but not for those with alcoholic pancreatitis (8.5% of n = 72). N. Sharer et al. New Engl J Med 1998;339:645-52

Author, Year affected patients %

Choudari et al., 1998 19/96 patients 19,8%

Sharer et al., 1998 11/60 patients 18,3%

Cohn et al., 1998 7/27 patients 25,9%

Ockenga et al., 2000 5/20 patients 25%

Maire et al., 2003 11/64 patients 17,1%

Weiß et al., 2005 12/66 patients 16,7%

Sharer et al., 1998 32/600 Control cohort 5,3%

Cohn et al. 2005 15/52 patients 17,3%

Frequency of CFTR-mutations in patients withidiopathic chronic pancreatitis – review of the literature

Prevalence of gene mutations in chronic pancreatitis

Idiopathic pancreatitis

45.5%Trypsinogen mutations

10%

SPINK-1 mutations

15.2%

T5 Allels

12.1%

CFTR mutations

18.2%

Genetics in pancreatic cancer - incidence

Genetic factors are responsible for 17% of all cases of pancreatic carcinoma.1.4 per 100.000 populations in Germany. Brentnall TA, Curr Treat Options Oncol 2005; 6: 437-445.

10% of patients with sporadic pancreatic carcinoma have a positive familyhistory for pancreatic cancer.

Prospective trial in pancreatic cancer families:Risk to develop pancreatic cancer: increased 9-times.If more than 3 family members are affected: 32-times Klein AP et al Cancer Research 2004; 64: 2634-2638

Retrospective trial in pancreatic cancer families to identify additional risk factorsSmoking. (87% (HPC) versus 66% (SPC) p = 0.006%)James TA et al. Cancer 2004; 101: 2722-2726

Hereditary Pancreatic Cancer Syndromes – FAMMM-PC

25% of all patients suffering from ‘Familial Atypical Multiple Mole Melanoma‘ Syndrome develop pancreatic cancer.

This disease is associated with mutations in the CDKN2A Gene (coding for the Cyclin dependent Kinase 2A = p16ink4a) [analogous p53 bei Li-Fraumeni]

Penetrance of these mutations is variable. The inheritance pattern follows a autosomal dominant trait.

Tumors are observed synchronous or metachronous.

Carrier of mutations in the CDKN2A gene have an 13- to 22-times increased risk for pancreatic cancer.

The Cumulative risk to develop pancreatic cancer until theage of 75 is estimated with 17%.

Borg A et al; J Nat. Cancer Inst 2000; 92: 1260-1266.

Hereditary Pancreatic Cancer Syndromes –Peutz-Jeghers-Syndrom

Autosomal dominant cancer syndrome with an incidence of 1:25 000.

Characterise by skin and mucosa pigmentationas well as multiple harmatous polyps.

Closely associated to mutations in theSerine/Threonine Kinase 11 (STK11), whichbelongs to the family of DNA-Repair genes.

Patients suffering from Peutz-Jeghers-Syndromehave a 132-times increased risk to developpancreatic cancer. The cumulative lifetime risk is 36% until the age of 75.

Jenne DE et al Nat Genet 1998; 18: 38-44.

Hamartom

Hereditary Pancreatic Cancer Syndromes –BRCA1 and BRCA2 Retrospective cohort study in patients(11.847 from 699 families) with a BRCA1 Mutations. Risk of pancreatic cancer: 2.26-times increased

10% of all cases with sporadic pancretic carcinoma (SPC) in Jews (Ashkenazim) are associated with BRCA2 mutations(6174delT). The prevalence of the 6174delT mutation in Jews is(Ashkenazim) 1%.

The prevalence of BRCA2 mutations in Americans withSPC is 17,2 %.The prevalence in Europe in patients withFamilial Pancreatic cancer (FPC) is 19%. No 6174delT mutations were detected in this cohort.

BRCA2 is the most frequent mutation associated withfamilial pancreatic cancer so far identified.

Thompson D et al, J Natl Canc Inst 2002; 94: 1358-1365; Ozcelik H et al Nat Genet 1997; 16:17-18; Murphy KM Cancer Research 2002; 62: 3789-3793; Rieder H et al Familial Cancer 2004; 3: 69-74.

BRCA2, Chromosome 13

BRCA1, Chromosome 17

Syndrome Gene Risk

HBOC BRCA1, BRCA2 ?HP PRSS1 40%PJS STK11/LKB 36%FAMMM-PC CDKN2A 17%

HBOC: Hereditäry Breast- and ovary-carcinoma SyndromHP: Hereditary PancreatitisPJS: Peutz-Jeghers-SyndromeFAMMM-PC: Familial multiple mole melanoma – pancreatic cancer syndrome

Hereditary Pancreatic Cancer Syndromes – Conclusion

Hahn SA et al, Gastroenterlogy Clinics of North America Gastro 2004, 2004; 33: 919-34

Genetics in pancreatic disease

Hereditary chronic and idiopathic chronic pancreatitis are associated with mutationsin the Trypsinogen gene, the SPINK-1 Gene, and the CFTR gene.

More genes to be evaluated.

Somatic mutations of proteins which influence tumor progression are closelyassociated with the development of pancreatic cancer (p53, k-ras, p16ink, DPC-4). Transgenic animal models have proven the relevance of these genes.

Familial pancreatic cancer syndromes are caused by germline mutations in generegulatory proteines and are burdened with a significantly increased life time risk of pancreatic cancer.

PRSS1 BRCA2SPINK1

Julia MayerlePeter SimonUli WeissMatthias Kraft

www.PANCREAS.de

In Zusammenarbeit mit

Hereditary chronic pancreatitis

Gene mutations in hereditary pancreatitis:

1996 identification of the R122H mutation in the cationic trypsinogen gene. (Whitcomb et al. Nat Gen 1996)

1998 Detection of gene mutations in the CFTR geneassociated with chronic pancreatitis. (Cystic Fibrosis) (Cohn et al., Sharer et al., New Engl J Med 1998)

2000 Detection of gene mutations in the secretory trypsin inhibitor gene associated to chronic pancreatitis. (SPINK-1, PSTI). (Witt et al., Nat Gen 2000)

Carcinogenesis of pancreatic carcinoma

Pancreatic cancer develops in a adenoma to carcinoma sequence.

Different genetic defects characterise the degree of dysplasia.

1A 3

flache papilläre

Hyperplasie Dysplasie CISInvasivesKarzinom

NormalesGangepithel

geringgradige hochgradige

PanIN 2g

mittelgradige

2m

K-ras LOH9p,17p,18q

p16?p53DPC4

1B

Hruban et al. Am J Surg Path 2004; 28: 977-987

Early genetic changes in pancreatic cancer – krasG12D

K (irsten) ras oncogene

pancreatic cancer is burdened with the highest incidence of k-ras mutations (55-95% of all investigated cancer samples).

79.1 % of all mutations are found in Codon 12 (at the position 71-79). Lüttges J et al, Cancer 2000; 88: 2495-2504

This suggests kras as key regulator in the tumorigenesis of pancreatic cancer.

PanINLesions90% in 6 Mo20% cancer

Tuveson DA et. al. Cancer Cell 2003; 4: 437

p53 encodes a transcription factor which is regarded as the „Guardian of the Genome“. p53 is induced byDNA-damage or activation of oncongenes.

Inactivtaion of p53 leads to the progression of the cell cyclevia G1/S-Phase what results in cell proliferation.

60% of all pancreatic carcinomas display mutations in the p53 gene and the gene isclosely associated with the Li-Fraumeni- Cancer-SyndromLi FP et al Cancer Research 1988; 48: 5358-5362.

G2Gap 2

MMitosis

G1Gap 1

G0Resting

SSynthesis

Rb

p53

p53 Mutations in Pancreatic Cancer –krasG12D /Trp53R172H

krasG12D /Trp53R172H transgenic animal

90 % of those animalsdie of pancreatic cancerMedian survival app. 5 monthsTuveson AD et al CancerCell 2005; 7: 469

Genetics of sporadic pancreatic carcinoma - Conclusion

Gene Locus LOH Mutation

K-ras 12p12 nd 93%p53 17p13 100% 70%p16ink 9p21 85% 78%DPC4 18q21.1 91% 50%

Pancreatic cancer is best studied for genetic alterations (somaticmutations) of all cancers.

Detection of these genetic lesions are so far of no diagnostic orprognostic value.

Studying transgenic animal models will help us to understandthe tumorigenesis in pancreatic cancer.