Bcl-2 expression significantly correlates with thymidylate synthase expression in colorectal cancer patients.
OBJECTIVE
To examine the expression of thymidylate synthase (TS) and oncoprotein Bcl-2 in advanced colorectal cancer (CRC) patients, and to determine their mutual relationship, association to therapeutic response and impact on disease outcome.


METHODS
Tumor samples from 67 patients with CRC, who were treated at advanced stage with either irinotecan alone or in combination with 5-fluorouracil/leucovorin, were analyzed for expression of TS and Bcl-2 using immunohistochemistry.


RESULTS
A significant linear correlation between lower expression levels of Bcl-2 and lower levels of TS expression was found (P = 0.033). Patients with high levels of both TS and Bcl-2 expression had a significantly longer disease-free survival (DFS) (42.6 mo vs 5.4 mo, n = 25) than those with low TS/Bcl-2 index (P = 0.001). Tumors with low levels of both TS and Bcl-2 were associated with a longer survival with metastasis (WMS) interval in the whole patients group (n = 67, P = 0.035). TS/Bcl-2 index was not significantly related to disease-specific survival.


CONCLUSIONS
The present data suggest that CRC patients with low TS/Bcl-2 demonstrate a significantly shorter DFS and longer WMS.
Bendardaf
Riyad
R
Department of Oncology and Radiotherapy, Turku University Hospital, Savitehtaankatu 1, PB 52, Turku FIN-20521, Finland. riyben@utu.fi
Ristamaki
Raija
R
Syrjanen
Kari
K
Pyrhonen
Seppo
S
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D014408:Biomarkers, Tumor / Q000032:analysis*; D015179:Colorectal Neoplasms / Q000737:chemistry* / Q000188:drug therapy / Q000201:enzymology / Q000473:pathology; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D011446:Prospective Studies; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis*; D018570:Risk Assessment; D013940:Thymidylate Synthase / Q000032:analysis*; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
D014408:Biomarkers, Tumor; D019253:Proto-Oncogene Proteins c-bcl-2; D013940:Thymidylate Synthase