Thymidylate synthase polymorphism in Mexican patients with colon cancer treated with 5-fluorouracil.
OBJECTIVE
We analyzed the genotype and allele frequency of variable number tandem repeats (VNTR)-thymidylate synthase (TS) and its relationship with the disease evolution in colon cancer patients.


METHODS
We selected 24 paraffin-embedded colon cancer tissue samples from Mexican patients who received a 5-fluorouracil (5-FU)-based chemotherapy regimen. Tumor tissue was digested with proteinase K and genomic DNA was isolated by the standard method with phenol-chloroform extraction. Polymerase chain reaction (PCR) was performed for TS genotyping of VNTR and the results were evaluated directly in a stained agarose gel.


RESULTS
The allele frequency of 2 repeats (2R) was greater (0.66) than 3R (0.34) in metastatic colon cancer (x2=10.24; p=0.001)) however, no difference in allelic distribution between 2R (0.54) and 3R (0.46) in non metastatic patients was observed (x2=0.640; p=0.424).


CONCLUSIONS
Our results suggest that Mexican patients with colon cancer present differences in the allelic distribution, the 2R allele being the most frequent.
Department of Biochemistry and Molecular Medicine, School of Medicine, Autonomous University of Nuevo Leon, Mexico (UANL).
Clara
C
Patricia Rios-Ibarra
Claudia
C
Janeth Rodriguez-Silva
Yamil
Y
Alonso Lopez-Chuken
Rocio
R
Ortiz-Lopez
Elisa
E
Fernandez-Castillo
Claudia
C
Beatriz Del Toro Runzer
Vicente
V
Paul Armenta-Perez
Juan Pablo
JP
Flores-Gutierrez
Arturo
A
Quintanilla-Guzman
Mauricio
M
Salinas-Santander
Juan Francisco
JF
Gonzalez-Guerrero
Francisco
F
Bosques-Padilla
Arturo
A
Santos
Herminia
H
Guadalupe Martinez-Rodriguez
D000328:Adult; D000368:Aged; D003110:Colonic Neoplasms / Q000188:drug therapy* / Q000235:genetics*; D005260:Female; D005472:Fluorouracil / Q000627:therapeutic use*; D005787:Gene Frequency / Q000235:genetics; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D018598:Minisatellite Repeats / Q000235:genetics*; D011110:Polymorphism, Genetic / Q000235:genetics*; D013940:Thymidylate Synthase / Q000235:genetics*; D055815:Young Adult
D013940:Thymidylate Synthase; D005472:Fluorouracil