Ana María Puebla-Pérez

The TP53 16-bp Duplication Polymorphism Is Enriched in Endometriosis Patients

Background/Aim: The TP53 tumor suppressor gene encodes the nuclear phosphoprotein p53, which plays an important role in cell cycle regulation, apoptosis, DNA repair and angiogenesis. The TP53 gene contains common genetic polymorphisms that influence gene activity. Clinical implications of TP53 polymorphisms have been reported for several diseases, including a variety of solid tumors and endometriosis. We evaluated the association of a TP53 duplication polymorphism with endometriosis. Methods: We evaluated the role of the TP53 16-bp duplication polymorphism by comparing the genotypes of 204 healthy women (controls with surgically excluded endometriosis) to the genotypes of 151 women with endometriosis in the Mexican population. Results: The observed genotype frequencies for controls and endometriosis patients were 0.5 and 5% for 16 bp+/+, 11 and 21% for 16 bp+/–, and 88.5 and 77% for 16 bp–/–, respectively. The odds ratio (OR) was 9.8 (95% CI 1.2–446.8; p = 0.01). The association was more evident when we compared the distribution of genotype 16 bp+/+ to genotype 16 bp+/–. In patients with moderate/severe endometriosis, the OR was 4.0 (95% CI 1.6–9.8; p = 0.003). Conclusion: Our data suggest that the 16-bp duplication polymorphism in TP53 contributes significantly to endometriosis susceptibility in the Mexican population.

Effect of Ginkgo biloba extract, EGb 761, on the cellular immune response in a hypothalamic–pituitary–adrenal axis activation model in the rat

We evaluated the effects of Ginkgo biloba extract (EGb 761) on the cellular immune response of rats with immunosuppression induced by activation of the hypothalamic-pituitary-adrenal (HPA) axis. Groups of five rats were subjected to chronic stress by the application of daily electric shocks (ES) over 7 days. This stress produced a significant decrement in the delayed-type hypersensitivity response (DTH) to dinitrofluorobenzene (DNFB), and a decrease in the proliferation index of splenocytes. Treatment with oral doses of the phytopharmaceutical EGb 761 (100 mg/kg per day over 7 days) restored both the DTH response to DNFB and the proliferation index. EGb 761 has stress-alleviating properties through its moderation of corticosterone levels. It also possesses antioxidant activity that may contribute to its effects on the immune response. Our observations indicate that the phytopharmaceutical EGb 761 possesses immunostimulatory properties.

Intron 4 VNTR (4a/b) Polymorphism of the Endothelial Nitric Oxide Synthase Gene Is Associated with Breast Cancer in Mexican Women

The endothelial nitric oxide synthase (eNOS) gene plays an important role in several biological functions. Polymorphisms of the eNOS gene have been associated with cancer. It has been suggested that the VNTR 4 a/b polymorphism may affect the expression of eNOS and contributes to tumor promotion in the mammary gland. We examined the role of the eNOS4 a/b polymorphism by comparing the genotypes of 281 healthy Mexican women with the genotypes of 429 Mexican women with breast cancer (BC). The observed genotype frequencies for control and BC patients were 0.6% and 0.7% for a/a (polymorphic); 87% and 77% for a/a (wild type); and 12% and 22% for a/b respectively. We found that the odds ratio (OR) was 1.9, with a 95% confidence interval (95%CI) of 1.29-2.95, P = 0.001 for genotypes a/a-a/b, b/c. The association was also evident when comparing the distribution of the a/a-a/b genotypes in patients with high levels of glutamate-oxaloacetate transaminase (SGOT) (OR, 1.93; 95% CI, 1.14-3.28; P = 0.015); undergoing menopause with high levels of SGOT (OR, 2.0; 95% CI, 1.1-3.84); and with high levels of glutamic-pyruvic transaminase (SGPT) (OR, 3.5; 95% CI, 1.56-8.22). The genotypes a/a-a/b are associated with BC susceptibility in the analyzed samples from the Mexican population.

The association between the 844ins68 polymorphism in the CBS gene and breast cancer

Introduction The cystathionine beta synthase (CBS) gene plays an important role in homocysteine metabolism because it catalyzes the first step of the transsulfuration pathway, during which homocysteine is converted to cystathionine. Polymorphisms of CBS have been associated with cancer. Material and methods We examined the role of the 844ins68 polymorphism by comparing the genotypes of 371 healthy Mexican women with the genotypes of 323 Mexican women with breast cancer (BC). Results The observed genotype frequencies for controls and BC patients were 1% and 2% for Ins/Ins, 13% and 26% for W/Ins, and 86% and 72% for W/W, respectively. We found that the odds ratio (OR) was 2.2, with a 95% confidence interval (95% CI) of 1.5–3.3, p = 0.0001. The association was also evident when comparing the distribution of the W/Ins-Ins/Ins genotypes in patients in the following categories: 1) menopause and high γ-glutamyltransferase (GGT) levels (OR of 2.17, 95% CI: 1.17–4.26, p = 0.02), 2) chemotherapy response and high lactate dehydrogenase (LDH) levels (OR 2.2, 95% CI: 1.08–4.4, p = 0.027), 3) chemotherapy response and high GGT levels (OR 2.46, 95% CI: 1.2–4.8, p = 0.007), and 4) body mass index (BMI) and III–IV tumor stage (OR 3.2, 95% CI: 1.2–8.3, p = 0.013). Conclusions We conclude that the genotypes W/Ins-Ins/Ins of the 844ins68 polymorphism in the CBS gene contribute significantly to BC susceptibility in the analyzed sample from the Mexican population.

Association of the Alu insertion polymorphism in the progesterone receptor gene with breast cancer in a Mexican population

Introduction The progesterone receptor (PR) gene plays an important role in reproduction-related events. Data on polymorphisms in the PR gene have revealed associations with cancer, particularly for the Alu insertion polymorphism, which has been suggested to affect progesterone receptor function and contribute to tumor promotion in the mammary gland. Material and methods We examined the role of the Alu insertion polymorphism in the PR gene by comparing the genotypes of 209 healthy Mexican women with those of 481 Mexican women with breast cancer (BC). Results The genotype frequencies observed in the controls and BC patients were 0% and 4% for T2/T2 (Alu insertion), 16% and 21% for T1/T2, and 84% and 75% for T1/T1 (Alu deletion), respectively. The obtained odds ratio (OR) was 1.7, with a 95% confidence interval (95% CI) of 1.1–2.6, p = 0.009, for the T1/T2–T2/T2 genotypes. The association was also evident when the distributions of the T1/T2–T2/T2 genotypes in patients in the following categories were compared: obesity grade II (OR = 1.81, 95% CI: 1.03–3.18, p = 0.039) and the chemotherapy response (OR = 1.91, 95% CI: 1.27–3.067, p = 0.002). Conclusions The T1/T2–T2/T2 genotypes of the Alu insertion polymorphism in the PR gene are associated with BC susceptibility in the analyzed Mexican population.

Immunomodulatory activity of Chilean Cyttaria species in mice with L5178Y lymphoma

The immunomodulatory effect of hydrosoluble extracts of four Chilean Cyttaria species (Discomycetes, Fungi) was assessed in mice with L5178Y lymphoma. Oral administration of 100 mg extract per day for 7 days enhanced the percentual phagocytosis and phagocytosis index in animals receiving Cyttaria berteroi, Cyttaria darwinii, Cyttaria espinosae and Cyttaria harioti extracts. Differences in the digestion index were observed in mice treated with C. darwinii and C. berteroi. In the delayed-type hypersensitivity model, only C. harioti was able to modify the immune response. The results suggest that intake of Cyttaria can improve the immune system of consumers.

Identification of immunodominant antigens of Mycobacterium bovis by expression library immunization

This study combines two methodologies - vector expression of a genomic library and proteomics - to identify immunogenic proteins of Mycobacterium bovis. Immunization of BALB/c mice with a plasmid DNA pool from the library, containing approximately 8000 clones, induced a humoral response that facilitated the detection of 12 antigenic proteins by Western blotting. Two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and mass spectrometry identified four proteins (Cpn60-1, HSP70, EF-Tu, and AdoHcyase). Such genomic immunization offers the possibility of in vivo screening of potential candidate M. bovis antigens.

Effect of Ditaxin and Heteranthin and Inhibitory Effect of Ditaxis heterantha Extract on L5178Y Tumor Development in Mice

Ditaxis heterantha seeds are used as spices for flavoring and coloring food. Two new apocarotenoids derived from the seeds, heteranthin and ditaxin, were evaluated for their in vitro cytotoxic effects in murine lymphoma cells lines. Bioabsorption in mice and preventive and antitumor effects of the apocarotenoids were determined. Ditaxin and heteranthin showed cytotoxic effects in vitro against murine malignant cells and normal splenocyte cells. The 50% inhibitory concentration (IC(50)) for ditaxin in splenocytes was 0.1825 mM; in L5178Y, the IC(50) was 0.1923 mM. The heteranthin IC(50) in splenocytes was 0.1325 mM; in L5178Y, the value was 0.3889 mM. The maximum ditaxin plasma concentration was found after 2 hours of administration (mean±standard deviation, 7.5±2.05 μg/mL). Oral administration of the D. heterantha extract (100 mg/kg per day) for 14 days after the L5178Y lymphoma cell implantation showed no significant effect compared with groups that were not pretreated. However, tumor inhibition in groups treated intraperitoneally before inoculation with the L5178Y cells showed a significant difference (P<.001) compared with the groups not pretreated.

TYMS 2R3R polymorphism and DPYD [IVS]14+1G>A gene mutation in Mexican colorectal cancer patients

OBJECTIVE To examine the association between TYMS 2R3R polymorphism and DPYD [IVS]14+1G>A mutation by comparing healthy subjects with colorectal cancer (CRC) patients in the Mexican population. METHOD Genotyping of the 2R/3R was performed by polymerase chain reaction (PCR) and [IVS]14+1G>A mutation by real-time PCR analysis. RESULTS The observed frequencies of the TYMS 2R3R polymorphism and the -[IVS]14+1G>A mutation in DPYD did not indicate an increased risk for CRC (p>0.05). However we observed an association of the 2R/2R (OR 3.08, 95% CI 1.66-6.08, p=0.0017) and heterozygous (OR 1.98, 95% CI 1.32-2.97, p=0.0012) genotypes as risk factors when comparing controls and CRC patients that were also tobacco consumers. An association between the genotype and the disease was evident. The distribution of the 2R/2R genotype and hematological toxicity (adjusted OR 2.26, 95% CI 1.54-4.45, p=0.0259), heterozygous (2R/3R) with tumor stage III-IV (OR 1.81, 95% CI 1.11-2.94, p=0.020) and 2R/2R-2R/3R in non-chemotherapy response CRC patients with hematological (OR 2.3, 95% CI 1.21-4.4, p=0.014) and gastric toxicities (OR 3.11, 95% CI 1.18-8.2, p=0.035) confirmed that this factor may significantly contribute to the CRC susceptibility. CONCLUSION TYMS 2R3R polymorphism and the -[IVS]14+1G>A mutation in DPYD was not associated with susceptibility to CRC. However, the 2R/2R and 2R/3R genotypes of TYMS polymorphism could significantly contribute to hematological and gastric toxicity in CRC patients in this sample population.

Association of the rs2279744 Promoter Polymorphism in the MDM2 Gene with Breast Cancer in a Mexican Population

Introduction: The MDM2 gene plays an important role as negative regulator of the p53 tumor suppressor. Data on polymorphisms in the MDM2 gene have revealed associations with cancer, particularly for the rs2279744 promoter polymorphism (309 T > G), which attenuates the P53 pathway and promotes tumorigenesis in the mammary gland. Material and Methods: We examined the role of the MDM2 309 T > G polymorphism through a comparison of the genotypes of 408 healthy Mexican women with those of 529 Mexican women with breast cancer (BC). Results: The genotype frequencies of the MDM2 309 T > G polymorphism in controls and BC patients were 25% and 23% for T/T (wild type), 50% in BC and controls for T/G, and 25 and 27% for G/G (polymorphic type), respectively. The obtained odds ratio (OR) was 1.07, with a 95% confidence interval (95% CI) of 0.79-1.45, p = 0.64 for the T/GG/ G genotypes. The association was evident when the distributions of the G/G genotypes in patients exhibiting the following characteristics were compared: breastfeeding >6 months (OR 2.1, 95% CI 1.3-3.4, p = 0.002), obesity (OR 1.8, 95% CI 1.2-2.7, p = 0.003) and high GGT levels (OR 1.7, 95% CI 1.1-2.5, p = 0.012). The genotype G/G of the MDM2 309 T > G. Conclusions: The MDM2 309 T > G polymorphism was associated with BC susceptibility, particularity in breastfeeding, obesity and high GGT levels in the analyzed Mexican population.