Thesis
MODELO MULTIGÉNICO DE IDENTIFICACIÓN DE MUJERES DE ALTO RIESGO A DESARROLLAR CÁNCER DE MAMA POR MEDIO DEL ANÁLISIS POLIMORFICO DE COMPT, CYP17, CYP1A1, CYP19 Y RECEPTOR DE ESTRÓGENO
Autor
M en C. MORENO GALVÁN, MÓNICA
Institución
Resumen
Background. In Mexico, between women with cancer, the breast cancer is in first
place like the cause of death. 65% of this women belong to the productive group
between 35 to 64 years of age. Furthermore, the number of women below 40 years
old affected with this kind of cancer is increased during the last five years. The
breast cancer represent an important problem in public health, that is the reason
because an urgent need to have a preventive alternative methods and secreening.
The present proposal analyze five genes polymorphism, related to the estrogen
carcinogenesis (COMPT, CYP17, CYP1A1, CYP19 and estrogen receptor), and
their breast cancer association in Mexican women.
Objective. To develop an identification of high risk women by a multigenetic model
for breast cancer.
Methods. We develop a cases and controls clinical study, where we select 100
breast cancer mexican women and 100 negative controls. We obtain DNA from
peripheral blood for genotyping COMT, CYP17, CYP1A1 and estrogen receptor by
PCR-RFLP, and by electrophoresis to CYP19. Genotype frequencies were
estimated for all participants in the study. The association between genotypes and
breast cancer risk was measured using a logistic regression likewise method to
obtain the Odds Ratio (OR) and its corresponding 95% Confidence Intervals (95%
CI) and adjusted for age. “p” values for chi-squared or Fisher exact tests were also
calculated. The statistic programs utilized was SPSS versión 14 y Epi-Info 3.5.1.
Results. The epidemiological factors independent analysis never show any breast
cancer significant association. The results showed a high risk of breast cancer in
women carrying the CYP1A1 (3801 T>C) m2/m2 genotype (OR=2.52; 95%CI=1.04-6.08). This risk was higher in postmenopausal women (OR=3.38;
95%CI=1.05-10.87). No association between COMT 1947 G>A CYP1A1m2,
CYP17, ER and breast cancer was found. Finally, we show gene CYP19 genotype
A21/A2 as a high risk to develop breast cancer (OR = 2.03; 95%CI= 0.96-4.26).
Conclusions. This study suggests that the CYP1A1 (3801 T>C) m2/m2 genotype
may contribute to breast cancer susceptibility in Mexican women. With this data
we proposed a risk model ready for validation.