Coordinate loss of fragile gene expression in pancreatobiliary cancers: correlations among markers and clinical features.
BACKGROUND
Loss of expression of fragile gene products, Fhit and Wwox, occurs in many cancer types, with loss exhibited early in the neoplastic process in some. Wwox has been understudied in pancreatobiliary cancers, especially in relation to other involved tumor suppressors. We have assessed the status of the Fhit and Wwox proteins encoded by DNA damage susceptible chromosome fragile sites encompassed by FHIT and WWOX tumor suppressor genes.


METHODS
Pancreatic, gallbladder and ampullary cancers, normal pancreas, chronic pancreatitis, and benign gallbladder specimens were stained for expression of Fhit, Fhit effector protein Fdxr, Wwox, and other tumor suppressors by immunohistochemistry, and comparisons were made between benign and malignant tissue. Correlations of expression among proteins and clinicopathologic features were sought using Spearman's rank order. Survival curves were created using the Kaplan-Meier method and compared by log-rank analysis. Predictors of survival were determined using multivariate Cox proportional hazards analysis.


RESULTS
Fhit and Wwox were ubiquitously expressed in benign samples and significantly and coordinately reduced in pancreatic, gallbladder, and ampullary cancers. In pancreatic cancers, Fdxr expression was positively correlated with Fhit and Wwox expression. Neither Fhit nor Wwox expression correlated with expression of other tumor suppressors or with clinicopathologic characteristics measured.


CONCLUSIONS
Loss of Fhit and Wwox expression does not predict tumor progression or patient survival, suggesting that loss of expression of genes at the exquisitely replication stress sensitive chromosome fragile regions is an early event in the pathogenesis of cancers of the gallbladder, pancreas, and ampulla.
Department of Surgery, The Ohio State University, Columbus, OH, USA. mark.bloomston@osumc.edu
Mark
M
Bloomston
Jeffrey
J
Kneile
Matthew
M
Butterfield
Mary
M
Dillhoff
Peter
P
Muscarella
E Christopher
EC
Ellison
W Scott
WS
Melvin
Carlo M
CM
Croce
Flavia
F
Pichiorri
Kay
K
Huebner
Wendy L
WL
Frankel
D017766:Acid Anhydride Hydrolases / Q000235:genetics / Q000378:metabolism*; D000368:Aged; D014670:Ampulla of Vater / Q000378:metabolism* / Q000473:pathology; D003138:Common Bile Duct Neoplasms / Q000378:metabolism* / Q000473:pathology; D005260:Female; D005706:Gallbladder Neoplasms / Q000378:metabolism* / Q000473:pathology; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology*; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism*; D009369:Neoplasms / Q000378:metabolism / Q000473:pathology; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D010190:Pancreatic Neoplasms / Q000378:metabolism* / Q000473:pathology; D011379:Prognosis; D015996:Survival Rate; D046888:Tissue Array Analysis; D025521:Tumor Suppressor Proteins / Q000235:genetics / Q000378:metabolism*; D000074584:WW Domain-Containing Oxidoreductase; D000099170:Bis(5'-adenosyl)triphosphatase
D017766:Acid Anhydride Hydrolases; D009363:Neoplasm Proteins; D010088:Oxidoreductases; D025521:Tumor Suppressor Proteins; D000074584:WW Domain-Containing Oxidoreductase; D000099170:Bis(5'-adenosyl)triphosphatase; C486071:WWOX protein, human