Poor prognosis of colorectal cancer in patients over 80 years old is associated with down-regulation of tumor suppressor genes.
GOALS, BACKGROUND: The elderly population has been increasing during the last half a century and it would be important to know how aging influences the occurrence and biologic behavior of cancers.


METHODS
We investigated clinicopathologic characteristics of colorectal cancer in 1354 patients who underwent colorectal cancer resection and compared the results between extremely elderly patients (over 80 years old) and middle-aged/elderly patients (40 to less than 80 years old). Furthermore, we also examined expression of tumor suppressor genes and Cox-2 using frozen samples of colorectal cancer obtained from 62 patients ranging in age from 45 to 87 years.


RESULTS
The results obtained in the extremely aged patients were: (1) higher ratio of women, (2) higher incidence at the proximal site, (3) higher incidence of cases with deeper invasion, (4) higher incidence of cases with lymph node metastasis (5) poorer survival rate as compared with middle-aged/elderly patients, and (6) lower mRNA expression levels of p27 and p53.


CONCLUSIONS
These findings taken together suggest that poor prognosis of colorectal cancer in patients over 80 years is associated with down-regulation of mRNA expression of some tumor suppressor genes.
Nagaoka
Sakae
S
Department of Pathology and Immunology, Aging and Developmental Sciences, Tokyo Medical and Dental University, Graduate School, Tokyo, Japan.
Shiraishi
Junichi
J
Utsuyama
Masanori
M
Seki
Sachiko
S
Takemura
Tamiko
T
Kitagawa
Masanobu
M
Sawabe
Motoji
M
Takubo
Kaiyo
K
Hirokawa
Katsuiku
K
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018797:Cell Cycle Proteins / Q000096:biosynthesis / Q000235:genetics; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D050760:Cyclin-Dependent Kinase Inhibitor p27; D051546:Cyclooxygenase 2; D015536:Down-Regulation / Q000235:genetics*; D005260:Female; D005500:Follow-Up Studies; D016147:Genes, Tumor Suppressor; D006801:Humans; D007527:Isoenzymes / Q000096:biosynthesis / Q000235:genetics; D008297:Male; D008565:Membrane Proteins; D008875:Middle Aged; D011379:Prognosis; D011451:Prostaglandin-Endoperoxide Synthases / Q000096:biosynthesis / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015996:Survival Rate; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis / Q000235:genetics; D025521:Tumor Suppressor Proteins / Q000096:biosynthesis / Q000235:genetics
D018797:Cell Cycle Proteins; D007527:Isoenzymes; D008565:Membrane Proteins; D012333:RNA, Messenger; D016159:Tumor Suppressor Protein p53; D025521:Tumor Suppressor Proteins; D050760:Cyclin-Dependent Kinase Inhibitor p27; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases