STAT3 activation is required for the antiapoptotic effects of prolactin in cervical cancer cells

BACKGROUND

Prolactin (PRL) has been implicated in the development of different types of cancer. However, signaling pathways might be activated depending on various forms of prolactin receptor (PRLR). JAK/STAT is an important pathway associated with PRL effects. The activation of JAK/STAT pathway might activate antiapoptotic genes that could importantly lead to progression of tumorigenesis. Recently, we have reported that PRL is associated with cell survival by inhibition of apoptosis and the precise activated signaling pathways for this process are still questioned. The purpose of this study was to evaluate the activation of different signaling pathways in response to PRL as well as to identify the induction of antiapoptotic genes.

METHODS

Cervical cancer cell lines HeLa, SiHa and C-33 A were stimulated with PRL (200 ng/mL) for 30 and 60 min and non stimulated cells were used to measure basal protein expression. Inhibition assays were performed by using Jak2 specific inhibitor AG490, either alone or in combination with PRL for 48 h. Western blot were carried out to evaluate protein induction of the different signaling pathways and antiapoptotic proteins. Significant effects were determined by using ANOVA test.

RESULTS

STAT3 was significantly activated in cervical cancer lines in comparison with non-tumorigenic keratinocytes HaCaT. No significant differences were found when analyzing MAPK and PI3K signaling pathways. An increase of antiapoptotic genes Bcl-xl, Bcl-2, survivin and Mcl-1 was observed after stimulus with PRL; however, after inhibition with AG490, the induction of antiapoptotic genes was decreased.

CONCLUSION

Our data suggests that STAT3 is an important signaling pathway activated by PRL in cervical cancer cells and it modulates the induction of antiapoptotic genes. Blocking STAT3 could represent a possible therapeutic strategy in cervical cancer.

Correlation of leptin and soluble leptin receptor levels with anthropometric parameters in mother-newborn pairs

The aim of this study was to investigate if anthropometric parameters are associated with both leptin and soluble leptin receptor (sLEPR) levels in newborns and their mothers. This cross-sectional study was performed in 118 mother-newborn pairs. The venous blood sample of mothers was taken before delivery and immediately after delivery an umbilical cord blood sample was collected. Levels of leptin and sLEPR in maternal and umbilical cord sera were assessed by ELISA. Maternal serum concentration of leptin and sLEPR (6.2 and 25.7 ng/ml, respectively) were higher than in umbilical cord blood (2.4 and 14.2 ng/ml, respectively). However, the newborns and their mothers had higher sLEPR levels than leptin levels. In mothers was observed that leptin levels increase with weight gain in pregnancy and decreased sLEPR levels. Cord leptin levels correlated with neonatal birth weight and length, the body circumferences, placental weight and maternal leptin levels. Cord sLEPR levels correlated with maternal sLEPR and leptin levels. Maternal serum concentration of leptin correlated with pre-pregnancy BMI, weight gain, cord sLEPR and leptin levels. Maternal sLEPR concentration correlated with cord sLEPR levels. The leptin and sLEPR levels in mother-newborn pairs are related with anthropometric parameters and an inverse correlation between leptin levels and sLEPR was observed in pairs.

Analysis of IL10 haplotypes in primary Sjögren's syndrome patients from Western Mexico: Relationship with mRNA expression, IL-10 soluble levels, and autoantibodies

Primary Sjögren's syndrome (pSS) is an autoimmune disease characterized by lymphocytic infiltration of salivary and lacrimal glands. Interleukin-10 (IL-10) plays a role in autoimmune diseases by promoting B-cell activation and autoantibodies production. IL10-1082A>G, -819C>T, -592C>A polymorphisms and their haplotypes have been associated with IL-10 production. The aim of this study was to associate IL10 haplotypes with mRNA expression and soluble IL-10 levels with susceptibility to pSS in 111 Mexican patients and 111 healthy subjects (HS). Primary Sjögren's syndrome patients showed high levels of sIL-10 (p=0.0001 vs HS) correlating with anti-Ro and anti-La antibodies (p<0.05). In addition, IL10 mRNA expression in pSS was higher than HS (0.8 vs 0.1, p=0.1537). However, no difference was observed in sIL-10 levels between haplotypes. Patients carriers of GCC haplotype showed higher mRNA expression than ACC+ATA (1.4 vs 0.6, p=0.2424) and high foci number (p=0.04 vs ACC). Our results suggest a strong relationship of IL10 with pSS which is demonstrated by the increased mRNA expression and also high sIL-10 levels positively correlated with autoantibodies. Besides that, the GCC haplotype carriers expressed high mRNA. However, IL10 haplotypes were not associated with sIL-10 in pSS from Western Mexico which suggest that diverse biological factors may regulate the IL10 expression in pSS.

Macrophage migration inhibitory factor (MIF) promoter polymorphisms (-794 CATT5-8 and -173 G>C): association with MIF and TNFα in psoriatic arthritis

Psoriatic arthritis (PsA) is an autoimmune disease with a complex interaction of gene and with a dysregulation of pro-inflammatory cytokine such as Macrophage migration Inhibitory Factor (MIF) and Tumor Necrosis Factor-alpha (TNFα). Two polymorphisms identified in the promoter region of the MIF gene have been described: the STR-794 CATT5-8 (rs5844572) and the SNP-173 G>C (rs755622), which are associated with increased MIF levels in circulation and with autoimmune diseases in several populations. In this case-control study we investigated whether commonly occurring functional MIF polymorphisms are associated with PsA susceptibility and clinical variables as well as with MIF and TNFα serum levels in a Mexican-Mestizo population. Genotyping of the -794 CATT5-8 and -173 G>C MIF polymorphisms was performed by PCR and PCR-RFLP respectively in 50 PsA patients and 100 healthy subjects (HS). MIF and TNFα serum levels were determined by ELISA. A significant increase of MIF (PsA: 7.8 vs. HS: 5.25 ng/mL; p < 0.001) and TNFα (PsA: 24.6 vs. HS: 9.9 pg/mL; p < 0.001) levels was found in PsA patients, a significant correlation was observed between MIF and TNFα (r = 0.41; p < 0.01). The 5,6 repeats genotype of the -794 CATT5-8 MIF was associated with protection to PsA (OR = 0.29; CI 0.77-0.98; p = 0.03), and the G/C genotype (OR = 7.5; CI 2.92-21.64; p < 0.001) and the -173*C allele (OR = 2.45; CI 1.43-4.20; p < 0.001) of the -173 G>C MIF were associated with susceptibility to PsA. In conclusion the -173*C allele is associated with susceptibility to PsA in Mexican-Mestizo population, whereas the correlation between MIF and TNFα soluble levels provided evidence that both cytokines are closely related in the pathophysiology of the PsA.

Tumor necrosis factor alpha -238 G/A and -308 G/A polymorphisms and soluble TNF-α levels in chronic kidney disease: correlation with clinical variables

Chronic kidney disease (CKD) is characterized by accumulation of proinflammatory cytokines, mainly tumor necrosis factor alpha (TNF-α). Single nucleotide polymorphisms (SNPs) of TNFA gene, including -238 G/A and -308 G/A, have been associated with alteration in the soluble TNF-α (sTNF-α) expression. The aim was to investigate the association of -238 y -308 TNFA gene SNPs with sTNF-α levels in CKD patients. We included 150 CKD patients and 192 control subjects (CS). Both SNPs were genotyped with polymerase chain reaction-restriction fragment length polymorphism technique and sTNF-α levels were measured by enzyme-linked immunosorbent assay. The genotypic distribution of -238 and -308 SNPs was not significantly different between CKD patients and CS (p > 0.001). However, the sTNF-α levels were higher in CKD, compared to CS (p < 0.001). Also, sTNF-α correlated with creatinine (r = 0.279, p = 0.004), urea (r = 0.325, p = 0.001), phosphorus (r = 0.479, p = 0.001), glomerular filtration rate (r = -0.236, p = 0.019) and monocyte count (r = 0.276, p = 0.010). In conclusion, elevated sTNF-α levels are associated with CKD. However, the -238 and -308 TNFA gene SNPs were not associated with susceptibility to CKD and sTNF-α levels in a Mexican population.

FAS -670A>G promoter polymorphism is associated with soluble Fas levels in primary Sjögren's syndrome

Primary Sjögren's syndrome (pSS) is a chronic systemic autoimmune disease characterized by lymphocytic infiltration of exocrine glands. Soluble Fas receptor (sFas) has been suggested as a Fas-mediated apoptosis blocker that could impair clonal deletion in infiltrated autoreactive cells. The FAS -670A>G promoter polymorphism has been studied in pSS. However, a relationship between FAS -670A>G promoter polymorphism and sFas levels in pSS had not been found. We examined this relationship in 77 Mexican pSS patients and 84 healthy subjects were included. Genotypes were identified by PCR-RFLP, and Fas soluble levels were quantified by ELISA. No significant differences between allele and genotype frequencies were found between these two groups. The sFas levels in the serum of pSS patients were significantly higher than in controls (9961 vs 8840 pg/mL, respectively). In addition, AA genotype carriers had significantly higher levels of sFas than GG carriers (pSS: 10,763 and 9422 pg/mL; controls: 9712 and 8305 pg/mL, respectively). An additive model analysis between genotypes (AG+GG vs AA) in both groups, demonstrated a significant association between carriers of the A allele and high sFas levels. In conclusion, carrying the double dose of A allele of FAS -670A>G polymorphism is associated with high levels of sFas in pSS, but it is not a susceptibility marker for pSS.

Circulating CD36 and oxLDL levels are associated with cardiovascular risk factors in young subjects

BACKGROUND

Cardiovascular disease (CVD) results from a combination of abnormalities in lipoprotein metabolism, oxidative stress, chronic inflammation, and susceptibility to thrombosis. Atherosclerosis is the major cause of CVD. CD36 has been shown to play a critical role in the development of atherosclerotic lesions by its capacity to bind and promote endocytosis of oxidized low-density lipoprotein (oxLDL) and is implicated in the formation of foam cells. The purpose of this research was to evaluate whether there is an association of sCD36 and oxLDL levels with cardiovascular risk factors in young subjects.

METHODS

A total of 188 subjects, 18 to 25 years old, 133 normal-weight and 55 obese subjects from the state of Guerrero, Mexico were recruited in the study. The lipid profile and glucose levels were measured by enzymatic colorimetric assays. Enzyme-linked immunosorbant assays (ELISA) for oxLDL and sCD36 were performed. Statistical analyses of data were performed with Wilcoxon- Mann Whitney and chi-square tests as well as with multinomial regression.

RESULTS

TC, LDL-C, TG, oxLDL and sCD36 levels were higher in obese subjects than in normal-weight controls, as well as, monocyte and platelet counts (P < 0.05). Obese subjects had 5.8 times higher risk of sCD36 in the third tertil (>97.8 ng/mL) than normal-weight controls (P = 0.014), and 7.4 times higher risk of oxLDL levels in third tertile (>48 U/L) than control group. The subjects with hypercholesterolemia, hypertriglyceridemia, fasting impaired LDL-C had a higher risk of oxLDL levels in the third tertile (>48 U/L) than the control group (P < 0.05).

CONCLUSIONS

Circulating CD36 and oxLDL levels are associated with cardiovascular risk factors in young subjects and may be potential early markers for cardiovascular disease (CVD).

Macrophage migration inhibitory factor: association of -794 CATT5-8 and -173 G>C polymorphisms with TNF-α in systemic lupus erythematosus

Macrophage migration inhibitory factor (MIF) is an upstream immunoregulatory cytokine associated with the pathogenesis of autoimmune inflammatory diseases. There is evidence that MIF functions in a positive feedback loop with TNF-α that could perpetuate the inflammatory process in systemic lupus erythematosus (SLE). In this case-control study we investigated whether commonly occurring functional MIF polymorphisms are associated with SLE as well as with MIF and TNF-α serum levels in a Mexican-Mestizo population. Genotyping of the -794 CATT5-8 (rs5844572) and -173 G>C (rs755622) MIF polymorphisms was performed by PCR and PCR-RFLP, respectively in 186 SLE patients and 200 healthy subjects. MIF and TNF-α serum levels were determined by ELISA. A significant increase of MIF and TNF-α levels was found in SLE patients. According to a genetic model, we found a significant association of genotypes carrying the -794 CATT7 and -173(∗)C risk alleles with susceptibility to SLE and with a significant increase of TNF-α. In conclusion, MIF gene polymorphisms are associated with SLE susceptibility and with an increase of TNF-α serum levels in a Mexican-Mestizo population.

CD36 haplotypes are associated with lipid profile in normal-weight subjects

Background

Dyslipidemia is a common metabolic disorder that may result from abnormalities in the synthesis, processing and catabolism of lipoprotein particles. Disorders of lipoprotein concentrations and elevated concentration of oxidized lipoproteins (oxLDL) are risk factors in the pathogenesis of cardiovascular diseases (CVD). CD36 plays an important role in lipid metabolism and polymorphisms in the CD36 gene are related to cardiovascular risk factors. The purpose of this study was to evaluate whether there is an association between genotypes and haplotypes of five polymorphisms in the CD36 gene with lipid levels in young normal-weight subjects.

Methods

A total of 232 unrelated subjects with normal-weight of 18 to 25 years old (157 women and 75 men) were randomly selected. The lipid profile and glucose levels were measured by enzymatic colorimetric assays. Genotyping of the polymorphisms -33137A/G (rs1984112), -31118G/A (rs1761667), -22674 T/C (rs2151916), 27645 Ins/Del (rs3840546) and 30294G/C (rs1049673) in the CD36 receptor gene was performed by polymerase chain reaction and restriction fragment length polymorphism, linkage disequilibrium analysis among the five polymorphisms and an analysis of haplotype were estimated.

Results

HDL-C levels was lower in men than in women (P = 0.03). However, the median oxLDL levels in men was higher than in women (P = 0.05). There was no significant difference in the levels of TC, TG, LDL-C and glucose (P > 0.05). HDL-C levels were lower in the subjects with TC genotype of polymorphism -22674 T/C (P = 0.04), but the carriers of TT genotype had lower oxLDL levels (P = 0.01). LDL-C levels were higher in young carriers of CC genotype for 30294G/C polymorphism than non-carriers (P = 0.03). The subjects carrying the AATDC haplotype had 3.2 times presumably higher risk of LDL-C > 100 mg/dL than the carrying the AGTIG haplotype (P = 0.02), whereas the subjects carrying the AATIC haplotype had 2.0 times presumably higher risk of TC > 200 mg/dL than the carrying the AGTIC haplotype (P = 0.02).

Conclusion

The study provides evidence of a genetic association of CD36 haplotypes with the variability in LDL-C and TC levels in a sample of normal-weight subjects.

High expression of prolactin receptor is associated with cell survival in cervical cancer cells

BACKGROUND

The altered expression of prolactin (PRL) and its receptor (PRLR) has been implicated in breast and other types of cancer. There are few studies that have focused on the analysis of PRL/PRLR in cervical cancer where the development of neoplastic lesions is influenced by the variation of the hormonal status. The aim of this study was to evaluate the expression of PRL/PRLR and the effect of PRL treatment on cell proliferation and apoptosis in cervical cancer cell lines.

RESULTS

High expression of multiple PRLR forms and PRLvariants of 60-80 kDa were observed in cervical cancer cell lines compared with non-tumorigenic keratinocytes evaluated by Western blot, immunofluorecence and real time PCR. Treatment with PRL (200 ng/ml) increased cell proliferation in HeLa cells determined by the MTT assay at day 3 and after 1 day a protective effect against etoposide induced apoptosis in HeLa, SiHa and C-33A cervical cancer cell lines analyzed by the TUNEL assay.

CONCLUSIONS

Our data suggests that PRL/PRLR signaling could act as an important survival factor for cervical cancer. The use of an effective PRL antagonist may provide a better therapeutic intervention in cervical cancer.

Associations of killer cell immunoglobulin- like receptor genes with rheumatoid arthritis

OBJECTIVE

Rheumatoid Arthritis (RA) is an autoimmune and chronic inflammatory disease of unknown etiology. Killer cell immunoglobulin-like receptors are expressed on the surface of natural killer cells and CD28null T-cells, both present in synovial membrane of RA. Therefore we evaluated the associations of KIR genes with RA.

METHODS

16 KIR genes were genotyped in 100 healthy subjects (HS) and 100 RA patients from Western Mexico using PCR-SSP. Differences in KIR genotypes and gene frequencies were assessed using the <formula>X^{2}</formula> test.

RESULTS

Gene frequency of KIR2DL3 was lower in RA than in HS (p= 0.0019), whereas KIR2DL2 and KIR2DS2 were higher in RA than HS (p =0.0004 and p = 0.0487, respectively). In addition were identified 38 genotypes (from G1-G38) in both studied groups, and the genotype frequencies of G1, G6 and G14 showed significant differences (p =0.0001, p =0.0208 and p =0.0300, respectively).

CONCLUSIONS

The presence of KIR2DL2, KIR2DS2 and absence of KIR2DL3 are associated with RA. Moreover, two genotypes BX are associated with RA. These results suggest that KIRs can be involved in RA susceptibility.

Maternal admixture and population structure in Mexican-Mestizos based on mtDNA haplogroups

The maternal ancestry (mtDNA) has important applications in different research fields, such as evolution, epidemiology, identification, and human population history. This is particularly interesting in Mestizos, which constitute the main population in Mexico (∼93%) resulting from post-Columbian admixture between Spaniards, Amerindians, and African slaves, principally. Consequently, we conducted minisequencing analysis (SNaPshot) of 11 mitochondrial single-nucleotide polymorphisms in 742 Mestizos of 10 populations from different regions in Mexico. The predominant maternal ancestry was Native American (92.9%), including Haplogroups A, B, C, and D (47, 23.7, 15.9, and 6.2%, respectively). Conversely, European and African ancestries were less frequent (5.3 and 1.9%, respectively). The main characteristics of the maternal lineages observed in Mexican-Mestizos comprised the following: 1) contrasting geographic gradient of Haplogroups A and C; 2) increase of European lineages toward the Northwest; 3) low or absent, but homogeneous, African ancestry throughout the Mexican territory; 4) maternal lineages in Mestizos roughly represent the genetic makeup of the surrounding Amerindian groups, particularly toward the Southeast, but not in the North and West; 5) continuity over time of the geographic distribution of Amerindian lineages in Mayas; and 6) low but significant maternal population structure (FST  = 2.8%; P = 0.0000). The average ancestry obtained from uniparental systems (mtDNA and Y-chromosome) in Mexican-Mestizos was correlated with previous ancestry estimates based on autosomal systems (genome-wide single-nucleotide polymorphisms and short tandem repeats). Finally, the comparison of paternal and maternal lineages provided additional information concerning the gender bias admixture, mating patterns, and population structure in Mestizos throughout the Mexican territory.

The integration of HR-HPV increases the expression of cyclins A and E in cytologies with and without low-grade lesions

Background:

Cyclin-A and cyclin-E are regulators of G1–S phase of normal cell cycle. Integration of human papilloma virus high-risk (HR-HPV) could alter this mechanism, and its overexpression has been associated with poor prognosis in cervical cancer.

Aim:

To determine the expression of cyclin-A and cyclin-E, types of HR-HPV and physical state of DNA in cytologies with the diagnosis of low-grade squamous intraepithelial lesion (LSIL).

Materials and Methods:

115 cytological specimens in liquid base (liquid-PREP^™) were analyzed. 25 specimens were with no signs of SIL (NSIL) and without HPV; 30 with NSIL with low-risk HPV (LR-HPV); 30 with NSIL with HR-HPV; and 30 with both LSIL and HR-HPV. The expression of cyclins was evaluated by immunocytochemistry; and the detection of viral DNA was done by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLPs) for genotyping or sequencing of HPV. The physical state of HPV was evaluated by in situ hybridization with amplification with tyramide.

Results:

In the cytologies NSIL with LR-HPV, the expression of cyclin-A and cyclin-E was found respectively in 23.3% and 33.3% of the specimens. Among the specimens of NSIL with HR-HPV, 33.3% expressed cyclin-A and 40% cyclin-E, while 100% of the LSILs expressed the 2 cyclins. On the other hand, 100% of the samples NSIL with LR-HPV presented an episomal pattern. Of the specimens of NSIL with HR-HPV, 56.6% exhibited an episomal pattern, 23.3% integrated and 20%, mixed. Among the LSILs, 90% were mixed and 10% integrated.

Conclusions:

The cyclins A and E are present in the LSILs that occur predominantly in mixed state in the presence of HR-HPV.

Macrophage migration inhibitory factor (MIF): genetic evidence for participation in early onset and early stage rheumatoid arthritis

Macrophage migration inhibitory factor (MIF) is an upstream pro-inflammatory cytokine that is associated with the pathogenesis of autoimmune inflammatory diseases including rheumatoid arthritis (RA). Two polymorphisms in the upstream region exist in the MIF gene and are associated with RA susceptibility or severity in different populations. In this case-control study, we investigated whether MIF polymorphisms are associated with RA susceptibility or activity in a western Mexican population .The relationship of MIF levels with clinical features of disease also was assessed. Genotyping of the -794 CATT5-8 (rs5844572) and the -173 G>C (rs755622) polymorphisms was performed by PCR and PCR-RFLP respectively on 226 RA patients and 210 healthy subjects. Serum MIF levels were determined by ELISA. We found a significant association between the -794 CATT5-8 6,7 MIF genotype with RA. Moreover, we detected an association between the -794 CATT7 allele with early onset RA. The -794 CATT7 and -173(*)C alleles, which are in linkage disequilibrium, were associated with high disease activity on RA patients. A positive correlation between circulating MIF levels and C-reactive protein, erythrocyte sedimentation rate, rheumatoid factor, anti-citrullinated protein/peptides antibodies and TNFα was detected. MIF levels appear to be associated with disease progression rather than disease activity, which is distinct from the established relationship between disease activity and TNFα levels. In conclusion, the MIF gene and protein are associated with RA in a western Mexican population, with a main contribution onto early onset and early stages of disease.

Distribution of CYP2D6 and CYP2C19 polymorphisms associated with poor metabolizer phenotype in five Amerindian groups and western Mestizos from Mexico

BACKGROUND

The distribution of polymorphisms in the CYP2D6 and CYP2C19 genes allows inferring the potential risk for specific adverse drug reactions and lack of therapeutic effects in humans. This variability shows differences among human populations. The aim of this study was to analyze single-nucleotide polymorphisms related to a poor metabolizer (PM) phenotype in nonpreviously studied Amerindian groups and Mestizos (general admixed population) from Mexico.

METHODS

We detected by SNaPshot(®) different polymorphisms located in CYP2D6 (*3, *4, *6, *7, and *8) and CYP2C19 (*2, *3, *4 and *5) in western Mestizos (n=145) and five Amerindian groups from Mexico: Tarahumaras from the North (n=88); Purépechas from the Center (n=101); and Tojolabales (n=68), Tzotziles (n=88), and Tzeltales (n=20) from the Southeast. Genotypes were observed by capillary electrophoresis. The genetic relationships among these populations were estimated based on these genes.

RESULTS AND DISCUSSION

The wild-type allele (*1) of both genes was predominant in the Mexican populations studied. The most widely observed alleles were CYP2C19*2 (range, 0%-31%) and CYP2D6*4 (range, 1.2%-7.3%), whereas CYP2D6*3 was exclusively detected in Mestizos. Conversely, CYP2C19*4 and *5, as well as CYP2D6*3, *6, *7, and *8, were not observed in the majority of the Mexican populations. The Tarahumaras presented a high frequency of the allele CYP2C19*2 (31%) and of homozygotes *2/*2 (10.7%), which represent a high frequency of potentially PM phenotypes in this Amerindian group. The genetic distances showed high differentiation of Tarahumaras (principally for CYP2C19 gene). In general, a relative proximity was observed between most of the Amerindian, Mexican-Mestizo, and Latin-American populations.

CONCLUSION

In general, the wild-type allele (*1) predominates in Mexican populations, outlining a relatively homogeneous distribution for CYP2C19 and CYP2D6. The exception is the Tarahumara group that displays a potentially increased risk for adverse reactions to CYP2C19-metabolized drugs.

Prehypertension in a Mexican population: influence of age, gender, and body fat

We studied the association of age, gender, and distribution of body fat with prehypertension in a sample of Mexican adults. This study was performed in a sample of 900 adults (275 men and 625 women), with the median age of 42 years. Resting blood pressure was measured in duplicate, and prehypertension and hypertension were defined according to JNC 7 criteria. The prevalence of hypertension and prehypertension in our population was 11.56% and 26.5%, respectively. The prevalence of prehypertension was significantly higher in men than in women. Prehypertension was associated with middle and old age (odds ratio [OR] = 2.6 and 2.4, respectively, P < .001), abdominal obesity (OR = 1.3, P = .008), upper quintiles of body mass index (OR = 2.05, P = .005), waist (OR = 1.97, P = .01) and hip (OR = 2.04, P = .005) circumferences, and body fat (OR = 2.37, P = .001). The main factors associated with the development of prehypertension are age, central obesity, and body fat.

Relationship of metabolic syndrome and its components with -844 G/A and HindIII C/G PAI-1 gene polymorphisms in Mexican children

Background

Several association studies have shown that -844 G/A and HindIII C/G PAI-1 polymorphisms are related with increase of PAI-1 levels, obesity, insulin resistance, glucose intolerance, hypertension and dyslipidemia, which are components of metabolic syndrome. The aim of this study was to analyze the allele and genotype frequencies of these polymorphisms in PAI-1 gene and its association with metabolic syndrome and its components in a sample of Mexican mestizo children.

Methods

This study included 100 children with an age range between 6-11 years divided in two groups: a) 48 children diagnosed with metabolic syndrome and b) 52 children metabolically healthy without any clinical and biochemical alteration. Metabolic syndrome was defined as the presence of three or more of the following criteria: fasting glucose levels ≥ 100 mg/dL, triglycerides ≥ 150 mg/dL, HDL-cholesterol < 40 mg/dL, obesity BMI ≥ 95^th percentile, systolic blood pressure (SBP) and diastolic blood pressure (DBP) ≥ 95^th percentile and insulin resistance HOMA-IR ≥ 2.4. The -844 G/A and HindIII C/G PAI-1 polymorphisms were analyzed by PCR-RFLP.

Results

For the -844 G/A polymorphism, the G/A genotype (OR = 2.79; 95% CI, 1.11-7.08; p = 0.015) and the A allele (OR = 2.2; 95% CI, 1.10-4.43; p = 0.015) were associated with metabolic syndrome. The -844 G/A and A/A genotypes were associated with increase in plasma triglycerides levels (OR = 2.6; 95% CI, 1.16 to 6.04; p = 0.02), decrease in plasma HDL-cholesterol levels (OR = 2.4; 95% CI, 1.06 to 5.42; p = 0.03) and obesity (OR = 2.6; 95% CI, 1.17-5.92; p = 0.01). The C/G and G/G genotypes of the HindIII C/G polymorphism contributed to a significant increase in plasma total cholesterol levels (179 vs. 165 mg/dL; p = 0.02) in comparison with C/C genotype.

Conclusions

The -844 G/A PAI-1 polymorphism is related with the risk of developing metabolic syndrome, obesity and atherogenic dyslipidemia, and the HindIII C/G PAI-1 polymorphism was associated with the increase of total cholesterol levels in Mexican children.

Increased expression of the prolactin receptor is associated with malignant laryngeal tumors

The altered expression of the prolactin receptor (PRLR) has been associated with the development of various types of cancer, particularly breast, prostate and endometrial cancer. However, in laryngeal tumors, the expression of PRLR has not yet been documented. The aim of this study was to determine the expression and localization of PRLR in laryngeal cancer (LC) in comparison with recurrent respiratory papillomatosis (RRP). PRLR expression was analyzed in 48 paraffin-embedded tissues (18 RRP and 30 laryngeal cancer tissues) by immunoperoxidase staining. Furthermore, PRLR expression was evaluated in ten samples from each group by Western blot analysis and quantitative real-time PCR. PRLR was observed in all laryngeal tumors at different intensities. PRLR overexpression was significantly associated (P<0.005) with LC. The staining pattern was homogeneous, mainly cytoplasmic, and confined to the tumor area. We found increased expression of different isoforms in LC in comparison with RRP. Our results suggest a possible role of PRL/PRLR in the development of LC. PRLR may be useful as a target for further investigations in laryngeal tissues.

Association of CD28 IVS3 +17T/C polymorphism with soluble CD28 in rheumatoid arthritis

OBJECTIVE

Rheumatoid arthritis (RA) is an autoimmune disease of unknown etiology in which inflammatory pathology involves T cell activation and the CD28 costimulatory molecule involved in T cell presentation. The gene includes the CD28 IVS3 +17T/C polymorphism that could be associated with susceptibility to RA whereas the soluble concentrations of CD28 (sCD28) could be related to clinical activity.

METHODS

We investigated the CD28 IVS3 +17T/C polymorphism in 200 RA patients and 200 healthy subjects (HS). Furthermore, we quantified the sCD28 concentrations in 77 samples of each group. We applied indexes focused to determine the activity and disability (DAS28 and Spanish HAQ-DI, respectively) in RA patients.

RESULTS

RA patients had significantly higher frequencies of the CD28 T allele compared to HS (p = 0.032 OR = 1.59, C.I. 1.02-2.49). In addition, the IVS3 +17 T/T genotype frequency was also increased in RA vs. HS (p = 0.026). The RA patients showed higher sCD28 serum levels than HS (p = 0.001). Carriers of the T/T genotype in RA patients showed higher sCD28 levels than C/C carriers (p =0.047). In addition, a correlation between sCD28 and Spanish HAQ-DI (correlation, 0.272; p =0.016), was found.

CONCLUSION

The T allele in CD28 IVS3 +17T/C polymorphism is associated with a susceptibility to RA in Western Mexico. In addition, increased sCD28 levels are related to T/T genotype in RA patients.

Circulating TNFRI and TNFRII levels correlated with the disease activity score (DAS28) in rheumatoid arthritis

OBJECTIVE

To measure levels of soluble tumour necrosis factor alpha (TNFalpha) receptor type I (sTNFRI) and type II (sTNFRII) in order to correlate them with C-reactive protein (CRP), rheumatoid factor (RF), erythrocyte sedimentation rate (ESR), and disease activity score (DAS28) in RA patients.

METHODS

We recruited 41 RA patients classified according to American College of Rheumatology (ACR) criteria and 38 healthy subjects (HS). sTNFRI and sTNFRII were measured using an enzyme-linked immunosorbent assay (ELISA) kit. Clinical activity in RA patients was evaluated using the Disease Activity Score using 28 joint counts (DAS28). The statistical analysis was realized using SPSS version 10.0.

RESULTS

Soluble TNFRI and TNFRII levels were higher in RA patients (p = 0.04 and 0.001, respectively) than HS. Serum levels of sTNFRI correlated with sTNFRII (r = 0.699, p < 0.0001). sTNFRII correlated with DAS28 (r = 0.375, p = 0.017), RF (r = 0.505, p = 0.004), and ESR (r = 0.323, p = 0.042).

CONCLUSION

The increased levels of both sTNFRI and sTNFRII suggest a secondary event related to the inflammatory state observed in RA, whereas the correlation of sTNFRII with RF, ESR, and DAS28 reflects the preferential TNFRII shedding induced by TNFalpha. sTNFRII may be useful as an additional inflammatory marker in RA.

Polymorphisms of alcohol metabolizing enzymes in indigenous Mexican population: unusual high frequency of CYP2E1*c2 allele

BACKGROUND

Alcohol abuse represents the major identified etiological factor of cirrhosis in México. ADH1B, ALDH2, and CYP2E1 have been considered candidate genes in alcohol-related diseases. Controversial results probably due to ethnic differences, among other factors, have been reported. Mexican Mestizos (MES) derive from the combination of indigenous, Spaniard, and African genes. Huichols (HUI) constitute an indigenous group from western Mexico with no racial admixture. We determined ADH1B*2, ALDH2*2, and CYP2E1*c2 allele frequencies in healthy HUI and MES from western Mexico. Lipid and hepatic profile were also carried out.

METHODS

One hundred and one HUI and 331 MES subjects were studied. Genotype and allele frequency were assessed through polymerase chain reaction-restriction fragment length polymorphism after DNA isolation from peripheral leukocytes. Commercial kits for lipid and hepatic determinations were used.

RESULTS

Polymorphic allele distribution in HUI was: 0%ADH1B*2, 0.5%ALDH2*2, 51.5%CYP2E1*c2; in MES: 3.4%ADH1B*2, 0%ALDH2*2, 16.1%CYP2E1*c2. Frequency of ADH1B*2 was statistically (p < 0.001) lower in HUI than MES. CYP2E1*c2 polymorphic allele was significantly higher (p < 0.0001) in HUI than MES. Hepatic profile was normal in both groups. HUI showed a better lipid profile than MES independently of genotype.

CONCLUSIONS

Huichols exhibited the highest CYP2E1*c2 allele frequency of the world documented up to this date; meanwhile, ADH1B*2 and ALDH2*2 were practically absent. This feature could be useful in the understanding of Mexican population gene composition, alcohol metabolism, and alcoholic liver disease development. However, further association studies are necessary. The heterogeneity of Mexican population was evidenced by the significantly different distribution of CYP2E1*c2 allele observed among different regions of the country. Lipid and hepatic values were not associated to genotype. This report constitutes the first study dealing with gene polymorphisms of alcohol metabolizing enzymes conducted in HUI.

Establishment of a cut-point value of serum TNF-alpha levels in the metabolic syndrome

Cardiovascular diseases and type 2 diabetes are the major causes of mortality in Mexico. Metabolic syndrome (MS) is a cluster of factors that increase the risk to develop such diseases. Previous studies have shown that MS is associated with high tumor necrosis factor (TNF-alpha) levels. In fact, TNF-alpha has been proposed to be a useful marker for clinical diagnosis of inflammation at an early stage. Therefore, we analyzed TNF-alpha concentrations in Mexican individuals with or without MS and related these levels to the associated MS components. Clinical, anthropometric, and biochemical data were analyzed in 41 healthy and 39 MS individuals. Individuals were similarly grouped by age and gender.The serum TNF-alpha levels measured by a highly sensitive enzyme-linked immunosorbent assay (ELISA) kit were increased significantly in MS subjects compared with healthy individuals (P<0.001). The assay showed 78.1% sensitivity and 61.5% specificity with a cut-point level of 1.36 pg/mL. TNF-alpha levels higher than the cut-point value were correlated with insulin resistance indices. These findings support the hypothesis that serum TNF-alpha concentration could be a useful marker for early MS diagnosis. Nevertheless, we suggest the establishment of specific cut-point values in each studied population to evaluate potential clinical applications.

Genetic data of 15 autosomal STRs (Identifiler kit) of three Mexican Mestizo population samples from the States of Jalisco (West), Puebla (Center), and Yucatan (Southeast)

We report autosomal STR data (Identifiler PCR amplification kit) of a total sample of 884 unrelated Mestizos from three different regions of Mexico. The population sample included 309, 313 and 262 individuals from the states of Jalisco (West), Puebla (Center) and Yucatan (Southeast), respectively. Allele distribution and forensic statistical parameters are described. Genotype distribution by locus and two-loci combination was in agreement with Hardy-Weinberg expectations for all 15 STRs. Pairwise comparisons including Mexican populations reported in the literature demonstrated a significant differentiation, principally between North/West with regard to Center/Southeast Mexico. These results increase STR data from previously unreported regions of this country, and constitute a valuable guide in forensic casework for choosing an auxiliary STR database in states where it is not available.