Margarita L. Martinez-Fierro

Identification of viral infections in the prostate and evaluation of their association with cancer

BackgroundSeveral viruses with known oncogenic potential infect prostate tissue, among these are the polyomaviruses BKV, JCV, and SV40; human papillomaviruses (HPVs), and human cytomegalovirus (HCMV) infections. Recently, the Xenotropic Murine Leukemia Virus-related gammaretrovirus (XMRV) was identified in prostate tissue with a high prevalence observed in prostate cancer (PC) patients homozygous for the glutamine variant of the RNASEL protein (462Q/Q). Association studies with the R462Q allele and non-XMRV viruses have not been reported. We assessed associations between prostate cancer, prostate viral infections, and the RNASEL 462Q allele in Mexican cancer patients and controls.Methods130 subjects (55 prostate cancer cases and 75 controls) were enrolled in the study. DNA and RNA isolated from prostate tissues were screened for the presence of viral genomes. Genotyping of the RNASEL R462Q variant was performed by Taqman method.ResultsR/R, R/Q, and Q/Q frequencies for R462Q were 0.62, 0.38, and 0.0 for PC cases and 0.69, 0.24, and 0.07 for controls, respectively. HPV sequences were detected in 11 (20.0%) cases and 4 (5.3%) controls. XMRV and HCMV infections were detected in one and six control samples, respectively. The risk of PC was significantly increased (Odds Ratio = 3.98; 95% CI: 1.17-13.56, p = 0.027) by infection of the prostatic tissue with HPV. BKV, JCV, and SV40 sequences were not detected in any of the tissue samples examined.ConclusionsWe report a positive association between PC and HPV infection. The 462Q/Q RNASEL genotype was not represented in our PC cases; thus, its interaction with prostate viral infections and cancer could not be evaluated.

Prime-boost BCG vaccination with DNA vaccines based in β-defensin-2 and mycobacterial antigens ESAT6 or Ag85B improve protection in a tuberculosis experimental model.

The World Health Organization (WHO) has estimated that there are about 8 million new cases annually of active Tuberculosis (TB). Despite its irregular effectiveness (0-89%), the Bacillus Calmette-Guérin) BCG is the only vaccine available worldwide for prevention of TB; thus, the design is important of novel and more efficient vaccination strategies. Considering that β-defensin-2 is an antimicrobial peptide that induces dendritic cell maturation through the TLR-4 receptor and that both ESAT-6 and Ag85B are immunodominant mycobacterial antigens and efficient activators of the protective immune response, we constructed two DNA vaccines by the fusion of the gene encoding β-defensin-2 and antigens ESAT6 (pDE) and 85B (pDA). After confirming efficient local antigen expression that induced high and stable Interferon gamma (IFN-γ) production in intramuscular (i.m.) vaccinated Balb/c mice, groups of mice were vaccinated with DNA vaccines in a prime-boost regimen with BCG and with BCG alone, and 2 months later were challenged with the mild virulence reference strain H37Rv and the highly virulent clinical isolate LAM 5186. The level of protection was evaluated by survival, lung bacilli burdens, and extension of tissue damage (pneumonia). Vaccination with both DNA vaccines showed similar protection to that of BCG. After the challenge with the highly virulent Mycobacterium tuberculosis strain, animals that were prime-boosted with BCG and then boosted with both DNA vaccines showed significant higher survival and less tissue damage than mice vaccinated only with BCG. These results suggest that improvement of BCG vaccination, such as the prime-boost DNA vaccine, represents a more efficient vaccination scheme against TB.

Ancestry informative markers and admixture proportions in northeastern Mexico

To investigate the ancestral admixture in the Mestizo population in northeastern Mexico, we genotyped 74 ancestral informative markers (AIMs) and 15 Y-single-nucleotide polymorphisms (Y-SNPs) in 100 individuals. The Native American contribution is 56% (range: 27.4–81.2%), the European contribution is 38% (range: 16.7–70.5%) and the West African contribution is 6%. The results show a higher European contribution than was reported in other similar studies in the country, albeit with a predominant Native American ancestry. No remarkable differences in the ancestry proportions were observed using subgroups of 74, 54, 34 and 24 AIMs. The paternal lineage calculated by genotyping of 15 Y-SNPs, shows a major component of European and Eurasian ancestry markers (∼78%), compared with Amerindian (∼12%) and African markers (10%). This information will set a reference for future determinations of admixture proportions in the Mestizo population from Mexico and for population-based association studies of complex diseases.

Analyses of chondrogenic induction of adipose mesenchymal stem cells by combined co-stimulation mediated by adenoviral gene transfer.

IntroductionAdipose-derived stem cells (ASCs) have the potential to differentiate into cartilage under stimulation with some reported growth and transcriptional factors, which may constitute an alternative for cartilage replacement approaches. In this study, we analyzed the in vitro chondrogenesis of ASCs transduced with adenoviral vectors encoding insulin-like growth factor-1 (IGF-1), transforming growth factor beta-1 (TGF-β1), fibroblast growth factor-2 (FGF-2), and sex-determining region Y-box 9 (SOX9) either alone or in combinations.MethodsAggregate cultures of characterized ovine ASCs were transduced with 100 multiplicity of infections of Ad.IGF-1, Ad.TGF-β1, Ad.FGF-2, and Ad.SOX9 alone or in combination. These were harvested at various time points for detection of cartilage-specific genes expression by quantitative real-time PCR or after 14 and 28 days for histologic and biochemical analyses detecting proteoglycans, collagens (II, I and X), and total sulfated glycosaminoglycan and collagen content, respectively.ResultsExpression analyses showed that co-expression of IGF-1 and FGF-2 resulted in higher significant expression levels of aggrecan, biglycan, cartilage matrix, proteoglycan, and collagen II (all P ≤0.001 at 28 days). Aggregates co-transduced with Ad.IGF-1/Ad.FGF-2 showed a selective expression of proteoglycans and collagen II, with limited expression of collagens I and × demonstrated by histological analyses, and had significantly greater glycosaminoglycan and collagen production than the positive control (P ≤0.001). Western blot analyses for this combination also demonstrated increased expression of collagen II, while expression of collagens I and × was undetectable and limited, respectively.ConclusionCombined overexpression of IGF-1/FGF-2 within ASCs enhances their chondrogenic differentiation inducing the expression of chondrogenic markers, suggesting that this combination is more beneficial than the other factors tested for the development of cell-based therapies for cartilage repair.

Association of chromosome 8q variants with prostate cancer risk in Caucasian and Hispanic men.

Genotyping of a 615 kb region within 8q24 with 49 haplotype-tagged single-nucleotide polymorphisms (SNPs) in 2109 samples (797 cases and 1312 controls) of two ethnic/racial groups found SNPs that are significantly associated with the risk for prostate cancer (PCa). The highest significance in Caucasian men was found for rs6983267; the AA genotype reduced the risk for PCa [odds ratio (OR) = 0.48, 95% confidence interval (CI) = 0.35-0.65, P = 2.74 x 10(-6)]. This SNP also had a significant independent effect from other SNPs in the region in this group. In Hispanic men, rs7837328 and rs921146 showed independent effects (OR = 2.55, 95% CI = 1.51-4.31, P = 4.33 x 10(-4), OR = 2.09, 95% CI = 1.40-3.12, P = 3.13 x 10(-4), respectively). Significant synergist effects for increasing numbers of high-risk alleles were found in both ethnicities. Haplotype analysis revealed major haplotypes, containing the non-risk alleles, conferred protection against PCa. We found high linkage disequilibrium between significant SNPs within the region and SNPs within the CUB and Sushi Multiple Domains 1 gene (CSMD1), on the short arm of chromosome 8 in both ethnicities. These data suggest that multiple interacting SNPs within 8q24, as well as different regions on chromosome 8 far beyond this 8q24 candidate region, may confer increased risk of PCa. This is the first report to investigate the involvement of 8q24 variants in the susceptibility for PCa in Hispanic men.

No association between polymorphisms/haplotypes of the vascular endothelial growth factor gene and preeclampsia

BackgroundPreeclampsia (PE) is the first worldwide cause of death in pregnant women, intra-uterine growth retardation, and fetal prematurity. Some vascular endothelial grown factor gene (VEGF) polymorphisms have been associated to PE and other pregnancy disturbances. We evaluated the associations between VEGF genotypes/haplotypes and PE in Mexican women.Methods164 pregnant women were enrolled in a case-control study (78 cases and 86 normotensive pregnant controls). The rs699947 (-2578C/A), rs1570360 (-1154G/A), rs2010963 (+405G/C), and rs25648 (-7C/T), VEGF variants were discriminated using Polymerase Chain Reaction - Restriction Fragment Length Polymorphism (PCR-RFLP) methods or Taqman single nucleotide polymorphism (SNP) assays.ResultsThe proportions of the minor allele for rs699947, rs1570360, rs2010963, and rs25648 VEGF SNPs were 0.33, 0.2, 0.39, and 0.17 in controls, and 0.39, 0.23, 0.41, and 0.15 in cases, respectively (P values > 0.05). The most frequent haplotypes of rs699947, rs1570360, rs2010963, and rs25648 VEGF SNPs, were C-G-C-C and C-G-G-C with frequencies of 0.39, 0.21 in cases and 0.37, 0.25 in controls, respectively (P values > 0.05)ConclusionThere was no evidence of an association between VEGF alleles, genotypes, or haplotypes frequencies and PE in our study.

Population based prostate cancer screening in north Mexico reveals a high prevalence of aggressive tumors in detected cases

BackgroundProstate Cancer (PCa) is the second most frequent neoplasia in men worldwide. Previous reports suggest that the prevalence of PCa in Hispanic males is lower than in Africans (including communities with African ancestry) and Caucasians, but higher than in Asians. Despite these antecedents, there are few reports of open population screenings for PCa in Latin American communities. This article describes the results of three consecutive screenings in the urban population of Monterrey, Mexico.MethodsAfter receiving approval from our University Hospitals Internal Review Board (IRB), the screening was announced by radio, television, and press, and it was addressed to male subjects over 40 years old in general. Subjects who consented to participate were evaluated at the primary care clinics of the University Health Program at UANL, in the Metropolitan area of Monterrey. Blood samples were taken from each subject for prostate specific antigen (PSA) determination; they underwent a digital rectal examination (DRE), and were subsequently interviewed to obtain demographic and urologic data. Based on the PSA (>4.0 ng/ml) and DRE results, subjects were appointed for transrectal biopsy (TRB).ResultsA total of 973 subjects were screened. Prostate biopsy was recommended to 125 men based on PSA values and DRE results, but it was performed in only 55 of them. 15 of these biopsied men were diagnosed with PCa, mostly with Gleason scores ≥ 7.ConclusionOur results reflect a low prevalence of PCa in general, but a high occurrence of high grade lesions (Gleason ≥ 7) among patients that resulted positive for PCa. This observation remarks the importance of the PCa screening programs in our Mexican community and the need for strict follow-up campaigns.

CYP2D6 gene polymorphisms and predicted phenotypes in eight indigenous groups from northwestern Mexico

AIM Polymorphisms in CYP2D6 impact the interindividual and interethnic variability of drug efficiency; therefore, we determined the CYP2D6 allele distribution in eight Amerindian groups from northwestern Mexico and compared them with the frequencies in Mexican Mestizos. MATERIALS & METHODS A total of 508 Amerindians were studied. Genotyping of CYP2D6*5 and multiplication alleles was performed by long-range PCR, while CYP2D6*2, *3, *4, *6, *10, *17, *29, *35, *41 and copy number were evaluated by real-time PCR. RESULTS The most frequent alleles were CYP2D6*2 (0.05-0.28), CYP2D6*4 (0.003-0.21) and multiplications (0.043-0.107). CYP2D6*5, *6, * 10 and *41 were not observed in the majority of Amerindians, and CYP2D6*3, *17, *35 and *29 were not detected. The poor metabolizer genotype ( *4/*5) was lower (0.2%) in Amerindians than in Mestizos (5%); conversely, the ultrarapid metabolizer genotype was higher (12.6%) in indigenous groups than in Mestizos (7%). CONCLUSION Our data show a lower frequency of CYP2D6 inactive alleles and a higher frequency of duplication/multiplication of CYP2D6 active alleles in indigenous populations that in Mestizos. Original submitted 14 August 2013; Revision submitted 7 October 2013.

Detection of sequences from a potentially novel strain of cell fusing agent virus in Mexican Stegomyia ( Aedes ) aegypti mosquitoes

Flaviviruses (FVs) are a very heterogeneous group of viruses that includes viruses capable of infecting insects and/or vertebrates. Different human-disease-causing FVs are disseminated by mosquitoes, and therefore, the search for FV in these insects has recently been proposed in order to evaluate their potential transmission in a given community. An entomological survey was carried out in Colima (the hyperendemic dengue fever transmission zone in Mexico) to collect culicidae in urban and wild areas. No human-pathogenic FVs were found, but sequences related to a potentially novel strain of cell fusing agent virus (CFAV) were detected in Stegomyia (Aedes) aegypti mosquitoes.

Positive association between vascular endothelial growth factor (VEGF) -2578 C/A variant and prostate cancer

BACKGROUND Vascular endothelial growth factor (VEGF) gene is an important angiogenesis regulator related to cancer development and progression. We evaluated the association between -2578 C/A (rs699947) VEGF polymorphism and PCa in Mexican subjects, to contribute to knowledge of VEGF role in genetic epidemiology of prostate cancer (PCa). OBJECTIVE The aim of this study was to evaluate the association between -2578 C/A VEGF variant and PCa in Mexican population. METHODS A total of 249 men (77 PCa cases and 172 controls) from the Northwestern region of Mexico were screened for the -2578 C/A VEGF variant. The polymorphism was determined by polymerase chain reaction-based restriction analysis. RESULTS Genotype frequencies for C/C, C/A, and A/A, were 0.48, 0.49, 0.03 for cases and 0.41, 0.45, 0.14 for controls respectively. Genotype A/A of -2578 VEGF variant reduces the risk of PCa in an 84% among studied population (Odds Ratio 0.16; 95% CI: 0.04-0.71, P=0.007). C/C carriers showed an increased PCa risk of 6.1 times among the study population. CONCLUSIONS Inheritance of -2578 A/A genotype of VEGF gene may modify PCa susceptibility risk in Mexican population.