Proton-sensing ion channels, GPCRs and calcium signaling regulated by them: implications for cancer.

Extracellular acidification of tumors is common. Through proton-sensing ion channels or proton-sensing G protein-coupled receptors (GPCRs), tumor cells sense extracellular acidification to stimulate a variety of intracellular signaling pathways including the calcium signaling, which consequently exerts global impacts on tumor cells. Proton-sensing ion channels, and proton-sensing GPCRs have natural advantages as drug targets of anticancer therapy. However, they and the calcium signaling regulated by them attracted limited attention as potential targets of anticancer drugs. In the present review, we discuss the progress in studies on proton-sensing ion channels, and proton-sensing GPCRs, especially emphasizing the effects of calcium signaling activated by them on the characteristics of tumors, including proliferation, migration, invasion, metastasis, drug resistance, angiogenesis. In addition, we review the drugs targeting proton-sensing channels or GPCRs that are currently in clinical trials, as well as the relevant potential drugs for cancer treatments, and discuss their future prospects. The present review aims to elucidate the important role of proton-sensing ion channels, GPCRs and calcium signaling regulated by them in cancer initiation and development. This review will promote the development of drugs targeting proton-sensing channels or GPCRs for cancer treatments, effectively taking their unique advantage as anti-cancer drug targets.

Whole-exome sequencing of pathogenic genes in a family with congenital heart disease: A case report.

RATIONALE: Congenital heart disease (CHD) is the most common birth defect and an important cause of noninfectious deaths in infants and children. It has high prevalence globally, placing an enormous burden on society and families. Studies of individuals with hereditary or sporadic CHD have provided strong evidence for its genetic basis. The aim of this study was to identify causative gene variants in a Chinese family with congenital heart disease. PATIENT CONCERNS AND DIAGNOSES: Three generations of a CHD family were recruited. Proband III.9 was diagnosed with congenital heart disease at age 11 months, and the echocardiogram showed arterial ductus arteriosus, with a left-to-right shunt at the level of the arteries. Precedent III.10 was a twin of Proband III.9 who was diagnosed with congenital heart disease at age 11 months, in whom the echocardiogram revealed an arterial ductus arteriosus, an unenclosed patent ductus arteriosus, and a left to right shunt at the level of the arteries (second figure). III.8 was diagnosed with congenital heart disease at age 15, but echocardiography in this study showed no abnormalities. No cardiac abnormalities were detected in any of his parents, grandparents, or maternal grandparents. We performed whole-exome sequencing on CHD sufferers and their unexpressing family members to investigate the genetic causes of CHD in this family line. Exome sequencing identified 4 mutation sites in this family line. The variant c.3245A>G (p.His1082Arg) of the AMER1 gene was consistent with concomitant X-chromosome recessive inheritance, the variant c.238G>C (p.Val80Leu) of the KCNE1 gene was consistent with autosomal accessory inheritance, and the other 2 variants did not conform to the law of the mode of inheritance of the disease. OUTCOMES: The first identified variant, c.3245A>G (p.His1082Arg) of the AMER1 gene, with X-chromosome recessive inheritance, and the variant c.238G>C (p.Val80Leu) of the KCNE1 gene, which has been reported as autosomal dominant, may be the causative agent of CHD in this family line. These findings broaden the genetic scope of congenital heart disease and could help in the development of targeted drugs for the treatment of congenital heart disease.

Types of milk consumed and risk of essential hypertension: A 2-sample Mendelian randomization analysis.

Observational associations between milk consumption and essential hypertension have been reported. However, their causal inferences have not been proven, and the effects of different types of milk consumption on hypertension risk remain poorly characterized. The Mendelian randomization (MR) analysis was performed using public summary-level statistics from genome-wide association studies to determine whether the different types of milk consumption affect essential hypertension differently. Six different milk consumption types were defined as exposure conditions, whereas essential hypertension identified by the ninth and tenth revisions of the International Classification of Diseases was considered the outcome of interest. Genetic variants, which were genome-wide associated with the types of milk consumed, were used as an instrumental variable for MR analysis. In primary MR analysis, the inverse-variance weighted method was adopted followed by several sensitivity analyses. Our findings suggested that of the 6 common types of milk consumed, semi-skimmed and soya milk products were protective against essential hypertension, whereas skim milk had the opposite effect. Consistent results were also observed in sensitivity analyses that followed. The present study provided genetic evidence that a causal link between milk consumption and the risk of essential hypertension and a new reference for the diet antihypertensive treatment plan for patients with hypertension.

Kidney ion handling genes and their interaction in blood pressure control.

Hypertension affects 30% of adults and is the leading risk factor for cardiovascular disease. Kidney sodium reabsorption plays a vital role in the initial stage and development of essential hypertension. It has been extensively reported that the variants of kidney ion handling genes are associated to blood pressure, and clinical features of hypertension. However, the underlying mechanisms by which these variants alter protein function are rarely summarized. In addition, the variation of one single gene is often limited to induce a significant effect on blood pressure. In the past few decades, the influence by genes × genes (G × G) and/or genotype × environment (G × E) interactions on a given trait, for example, blood pressure, have been widely considered, especially in studies on polygenic genetic traits. In the present review, we discuss the progress in genetics studies on kidney ion handling genes, encoding Na+ channels (Na+-Cl- cotransporter [NCC], Na-K-2Cl cotransporter [NKCC2], epithelial Na+ channels [ENaCs]), K+ channel (renal outer medullary potassium channel [ROMK]), and Cl- channels (Pendrin, chloride voltage-gated channel Kb [CLC-Kb]), respectively, and their upstream kinases, WNKs and SGK1. We seek to clarify how these genes are involved in kidney sodium absorption and influence blood pressure, especially emphasizing the underlying mechanisms by which genetic variants alter protein functions and interaction in blood pressure regulation. The present review aims to enhance our understanding of the important role of kidney ion handling genes/channels in blood pressure control.

Association between the ABCA1 (R219K) polymorphism and lipid profiles: a meta-analysis.

Conflicting evidence was found about the relationship between lipid profiles and R219K polymorphism in adenosine triphosphate-binding cassette exporter A1 (ABCA1) gene. In this study, four meta-analyses were conducted to assess the effect of R219K on lipid levels, including high-density lipoprotein cholesterol (HDLC), low-density lipoprotein cholesterol, total cholesterol, and triglycerides (TG). A total of 125 samples of 87 studies (about 60,262 subjects) were included. The effect of each study was expressed using the standard mean difference (SMD) and 95% confidence interval (95% CI) and pooled by meta-analysis in the random-effects model. Subgroup and meta-regression analyses were conducted to explore potential heterogeneity sources. The overall pooled effect showed the following results. (1) The R219K was significantly associated with HDLC level (SMD = - 0.25 mmol/L, 95%CI - 0.32 to - 0.18, z = - 6.96, P < 0.01, recessive genetic model). People with different genotypes had significantly different HDLC levels under the recessive, codominant and dominant genetic models (all Ps < 0.01). (2) A weak and indeterminate relationship between R219K and TG level was observed (SMD = 0.18 mmol/L, 95%CI 0.06-0.30, z = 3.01, P < 0.01, recessive genetic model). These findings suggested that R219K was associated with HDLC and TG levels, which might implicate a promising clinical application for lipid-related disorders, though the influences of race, health status, BMI, and other heterogeneity sources should be considered when interpreting current findings. The protocol was registered at PROSPERO (registration number: CRD42021231178).

Clinical Value of C-Reactive Protein/Platelet Ratio in Neonatal Sepsis: A Cross-Sectional Study.

PURPOSE: C-reactive protein (CRP) level and platelet (PLT) count have been demonstrated to be independent risk factor for neonatal sepsis. However, no data is currently available in regarding the association between CRP-to-PLT ratio (CPR) and neonatal sepsis. METHODS: A total of 1048 neonates with suspected sepsis were enrolled in this study. Complete clinical and laboratory data were collected. CPR was calculated as CRP (mg/L)/PLT (107 cells/L). Multivariate logistic regression analysis was performed to identify the potential independent risk factors of neonatal sepsis. Receiver operating characteristic (ROC) curve analysis was used to evaluate the prediction accuracy of CPR in predicting neonatal sepsis. RESULTS: Neonates with sepsis had a higher CPR. CPR also showed a gradual increase in the infection, mild sepsis and severe sepsis groups. Multivariate analysis revealed that CPR was a significant independent predictor of the presence of neonatal sepsis (odds ratio [OR], 1.015; 95% confidence interval [CI], 1.008-1.022, P < 0.001) and severe sepsis (OR, 1.002; 95% CI, 1.000-1.003, P = 0.007). ROC curve revealed showed that CPR had a well-discriminatory power in predicting sepsis (area under curve [AUC], 0.68; 95% CI, 0.65-0.72, P < 0.001) and severe sepsis (AUC, 0.68; 95% CI, 0.65-0.72, P < 0.001). CONCLUSION: The present study demonstrated that a higher CPR is an independent predictor of the presence and severity of neonatal sepsis.

Study on the Relationship Between Respiratory Distress Syndrome and SP-A1 (rs1059057) Gene Polymorphism in Mongolian Very Premature Infants.

Aim: To study the relationship between rs1059057 polymorphism of pulmonary surfactant protein A1 (SP-A1) and respiratory distress syndrome (RDS) in Mongolian very premature infants. Methods: Applying the strategy of case-control study, 120 Mongolian RDS very premature infants (58 males and 62 females) in the western part of Inner Mongolia were selected as the case group, and 120 subjects of non-RDS very premature infants (56 males and 64 females) with the same nationality, same sex and similar gestational age were used as the control group. The single nucleotide polymorphism (SNP) site rs1059057 of SP-A1 was genotyped using polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP). Results: Two genotypes, A/G and A/A, were detected at the SP-A1 rs1059057 locus in the western part of Inner Mongolia. In the case group, the frequencies of two genotypes were 53 and 47%, and the frequencies of A allele and G allele were 73 and 27%, respectively. In the control group, the frequencies of the two genotypes were 42 and 58%, and the frequencies of A allele and G allele were 79 and 21%, respectively. There was no significant difference in the genotype frequency of SP-A1 (rs1059057) locus between the case group and the control group (X 2 = 3.275, P > 0.05), and no significant difference in allele frequency between the case group and the control group (X 2 = 2.255, P > 0.05). Conclusion: The genotypes and allele frequencies of SP-A1 (rs1059057) locus were not associated with the incidence of RDS in Mongolian very premature infants in western Inner Mongolia.

Genetic variants of SLC12A3 modulate serum lipid profiles in a group of Mongolian pedigree population.

BACKGROUND: The serum lipid profile, including LDL-C level, is associated with hypertension which is the major cause of cerebrovascular disease (CVD) amounting 30% of global death rate. Previous work also demonstrated important roles of genetic variants of SLC12A3 gene on human CVD, hypertension and other diseases in Mongolian population. However, the relationship between SLC12A3 gene polymorphisms on individuals' lipid profile is still unknown. METHODS: A panel of 15 SNPs of SLC12A3 gene was genotyped within a 424 Mongolians pedigree cohort. The associations between SLC12A3 polymorphisms and four lipid profiles were analyzed by family-based association test (FBAT) and confirmed with haplotype analysis. RESULTS: From both single site and haplotype analyses, the results demonstrated a close relationship between SLC12A3 polymorphisms and LDL-C level. Two SNPs, rs5803 and rs711746 showed significant associations with individuals' serum LDL-C level (z = - 2.08, P -e = 0.038; z = 2.09, P -e = 0.023, respectively), and distribution of haplotypes constructed by two SNPs also associated with participants' serum LDL-C level, significantly (Global Chi2 = 9.06 df = 3, P = 0.028). CONCLUSION: Our results demonstrated the importance of SLC12A3 polymorphisms in individuals' difference about their serum lipid profiles, thereby providing evidence that the genetic variants may contribute to CVD development via modulating person's LDL-C level and blood pressure, in certain contexts.

SLC12A3 variants modulate LDL cholesterol levels in the Mongolian population.

BACKGROUND: Abnormalities in lipid metabolism are crucial factors in the pathogenesis of cardiovascular disease (CVD). Variants of many genes have been verified to confer risk for lipid metabolism abnormalities. However, the relationship between genetic variants of the NCC-encoding SLC12A3 gene and lipid metabolism in the Mongolian population remains unclear. In the present study, we aimed to elucidate the effects of SLC12A3 variants on Mongolian lipid metabolism, including total cholesterol (TCHO), triglycerides (TG), low-density lipoprotein cholesterol (LDL-c), and high-density lipoprotein cholesterol (HDL-c). METHODS: A randomly selected population of Mongolians (n = 331) from China underwent clinical testing. An ANOVA test, Kruskal-Wallis H test (K-W test) and haplotype analysis were used to evaluate the association between the levels of lipids (TCHO, TG, LDL-c, and HDL-c) and polymorphisms in SLC12A3 loci. RESULTS: We identified three single nucleotide polymorphisms (SNPs) rs5803, rs2010501 and rs711746 in the SLC12A3 gene that were significantly associated with an individual's serum LDL-c level. Haplotypes combining these SNPs also showed the same trend (all p values < 0.01). Furthermore, the influence of SLC12A3 genetic polymorphisms on differences in individual serum LDL-c levels remained significant, even after we controlled gender, and demographic and other non-genetic factors. CONCLUSION: These results suggest that variants of the SLC12A3 gene confer susceptibility to the abnormal serum LDL-c level in the Mongolian population.

Polymorphisms in the SLC12A3 Gene Encoding Sodium-Chloride Cotransporter are Associated with Hypertension: A Family-Based Study in the Mongolian Population.

BACKGROUND/AIMS: Hypertension or persistent high blood pressure (BP) is a leading cause of death worldwide. Extensive evidence indicates that the thiazide-sensitive Na+-Cl- cotransporter (NCC) affects BP via regulation of renal sodium reabsorption. However, the relationship between genetic variants of the NCC-encoding SLC12A3 gene and hypertension in the Mongolian population is still ambiguous. In this study, we aimed to genotype an extended cohort of hypertensive Mongolian families for polymorphisms in the SLC12A3 locus. METHODS: Eighty-eight families with a history of hypertension, including parents, offspring, and relatives underwent clinical testing. Family-based association tests and haplotype analysis were used to evaluate the association between hypertension and polymorphisms in the SLC12A3 locus. RESULTS: We identified three single nucleotide polymorphisms (SNPs), one in the SLC12A3 coding region (p = 0.05) and two in the intron (p = 0.02 and p = 0.07), which were significantly associated with the hypertension phenotype. Haplotype-specific association tests confirmed the correlation of these SNPs with hypertension (p < 0.05). CONCLUSION: These results suggest that SNPs in the SLC12A3 gene confer susceptibility to hypertension in the Mongolian population. Further research is needed to validate the functional role of SLC12A3 polymorphisms in hypertension.

Extracellular acidification synergizes with PDGF to stimulate migration of mouse embryo fibroblasts through activation of p38MAPK with a PTX-sensitive manner.

The elucidation of the functional mechanisms of extracellular acidification stimulating intracellular signaling pathway is of great importance for developing new targets of treatment for solid tumors, and inflammatory disorders characterized by extracellular acidification. In the present study, we focus on the regulation of extracellular acidification on intracellular signaling pathways in mouse embryo fibroblasts (MEFs). We found extracellular acidification was at least partly involved in stimulating p38MAPK pathway through PTX-sensitive behavior to enhance cell migration in the presence or absence of platelet-derived growth factor (PDGF). Statistical analysis showed that the actions of extracellular acidic pH and PDGF on inducing enhancement of cell migration were not an additive effect. However, we also found extracellular acidic pH did inhibit the viability and proliferation of MEFs, suggesting that extracellular acidification stimulates cell migration probably through proton-sensing mechanisms within MEFs. Using OGR1-, GPR4-, and TDAG8-gene knock out technology, and real-time qPCR, we found known proton-sensing G protein-coupled receptors (GPCRs), transient receptor potential vanilloid subtype 1 (TRPV1), and acid-sensing ion channels (ASICs) were unlikely to be involved in the regulation of acidification on cell migration. In conclusion, our present study validates that extracellular acidification stimulates chemotactic migration of MEFs through activation of p38MAPK with a PTX-sensitive mechanism either by itself, or synergistically with PDGF, which was not regulated by the known proton-sensing GPCRs, TRPV1, or ASICs. Our results suggested that others proton-sensing GPCRs or ion channels might exist in MEFs, which mediates cell migration induced by extracellular acidification in the presence or absence of PDGF.

Genetic variations of FACL4 have no obvious influence on cognitive ability in young Chinese children.

The influence of genetic variants of FACL4 on individual cognitive ability was examined in a random sample of 213 boys and 224 girls. Both conventional genetic methods and analysis of variance were applied in this study. We found no significant relationship between FACL4 and cognitive function.

No association between polymorphisms in the FACL4 (fatty acid-CoA ligase 4) gene and nonspecific mental retardation in Qin-Ba mountain region of China.

Mental retardation (MR) is a common form of cognitive impairment among children. The underlying causes of mental retardation are extremely heterogeneous and include significant genetic factors. Long chain fatty acid-CoA ligase 4 is the first gene shown to be involved in mental retardation and fatty-acid metabolism. FACL4 gene mutations in three Italian MR pedigrees have been reported as causing non-specific mental retardation. To investigate the possible genetic contribution of the FACL4 gene to non-specific mental retardation children of the Qin-Ba mountain region in China we performed an association study of 556 subjects (118 NSMR, 116 borderline NSMR, and 322 controls) from the Han children of northwestern China using five common SNPs (rs5943427, rs12856122, rs5943418, rs7886473, and rs10126612) in the gene. No significant differences of genotypes and alleles frequencies from each single SNP between NSMR and controls were observed. Pairwise linkage disequilibrium analysis showed that four SNPs rs5943427, rs12856122, rs5943418, and rs7886473 were in strong linkage disequilibrium; therefore, a haplotype analysis was performed. However, there were no any significant differences in haplotype distributions between cases and controls. In conclusion, we have found no evidence for the FACL4 gene conferring susceptibility on non-specific mental retardation children of the Qin-Ba mountain region in China.

An association study between cathechol-O-methyltransferase gene and mental retardation in the Chinese Han population.

Cathechol-O-methyltransferase (COMT) regulates the amount of dopamine in the prefrontal cortex (PFC). Substantial studies indicate a close relationship between COMT and several human psychotic disorders. The case-control method was used to study the association between mental retardation (MR) and genetic variants of COMT. Three single nucleotide polymorphisms (SNPs: rs4680, rs165656 and rs165774), in the cathechol-O-methyltransferase (COMT) gene, were genotyped by PCR-RFLP method. Individual SNP analysis shows significant differences only at SNP rs165656 for both genotype and allele frequency when comparing MR cases and controls (p=0.023, 0.011, respectively). Further haplotype analysis indicates that there are two haplotype sets, rs165656-rs4680 and rs165656-rs165774, which show statistical differences between MR cases and controls (global p=0.047, p=0.033, respectively). Our results suggest a positive association between the genetic variants of the COMT gene and MR in the Chinese Han population in the Qinba region.