SLCO1B1 Research Articles

Relationship between SLCO1B1 polymorphisms and methotrexate intolerance in Mexican children with juvenile idiopathic arthritis.

The most frequent adverse events (AEs) of methotrexate (MTX) are gastrointestinal symptoms and hepatotoxicity, which can affect its adherence, leading to reduced effectiveness. The SLCO1B1 gene codes for a liver protein (OATP1B1) responsible for drug transportation. Genetic variations within the SLCO1B1 gene locus impact drug transport, leading to altered pharmacokinetic profiles, delayed MTX clearance, and increased risk of toxicity. This study aimed to determine the association between single nucleotide polymorphisms (SNPs) in the SLCO1B1 gene (rs4149056, rs2306283) with the development of AEs in patients with juvenile idiopathic arthritis (JIA) treated with MTX. We performed an observational retrospective study to analyze the relationship between SNPs in the SLCO1B1 gene and the development of AEs in pediatric patients treated with MTX for JIA. Thirty patients with JIA were included, 22 females (73.3%), with a median age of 11years (IQR 8.3-15). The most frequent JIA subtype was rheumatoid factor-positive polyarthritis (36.7%). Twenty patients (66.7%) reported AEs. The *1B haplotype was the most frequent in this group (53.3%) and conferred a higher risk of developing AEs (OR = 3.89, 95% CI = 1.23 -12.29, p = 0.03). Patients with the allele *1B may benefit from lower doses of MTX. SLCO1B1 genotyping is a promising technique to identify patients at higher risk of AEs during treatment with MTX, thus requiring dose optimization.

Association Between ABCC2 -24C>T and Nab-Paclitaxel-induced Peripheral Neuropathy in Japanese Patients With Pancreatic Cancer.

Nab-paclitaxel is used to treat patients with pancreatic cancer. However, it frequently induces peripheral neuropathy. Notably, pharmacokinetic factors may be associated with neuropathic symptoms as the onset depends on the cumulative dose. Therefore, we prospectively examined the association between the cumulative dose of nab-paclitaxel at the onset of peripheral neuropathy and polymorphisms of hepatic transporter genes. Patients with pancreatic cancer receiving nab-paclitaxel (125 mg/m2) and gemcitabine (1,000 mg/m2) were enrolled. Peripheral neuropathy was assessed using the Common Terminology Criteria for Adverse Events (CTCAE), Patient-Reported Outcomes CTCAE (PRO-CTCAE), and Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity (FACT/GOG-Ntx), every 2-12 weeks, and every 4 weeks thereafter. solute carrier organic anion transporter family member 1B1 (SLCO1B1) 521T>C, 388A>G; SLCO1B3 rs11045585; ATP-binding cassette transporters, subfamily B, member 1 (ABCB1) 1236C>T, 2677G>T/A, 3435C>T; ABCC1 rs2644983; ABCC2 24C>T; and ABCG2 421C>A were analyzed by direct sequencing. Correlations between transporter genotypes and cumulative dose at symptom onset were assessed using Kaplan-Meier and log-rank tests. In total, 25 patients were enrolled. The lowest median cumulative dose for nab-paclitaxel at peripheral neuropathy onset using PRO-CTCAE was 593 mg. By CTCAE it was 800 mg, and by FACT/GOG-Ntx it was 1,090 mg (p<0.0001). At symptom onset, patients with ABCC2 -24C/T genotype had received a significantly lower median cumulative dose by PRO-CTCAE (540 mg) than those with C/C (720 mg) (p=0.0188). However, the other polymorphisms studied were not associated with symptoms. Herein, we found for the first time that ABCC2 -24C/T genotype was significantly associated with the onset of nab-paclitaxel-induced peripheral neuropathy detected with PRO-CTCAE.

Regulation of hepatic transporters OATP1A2 and OATP1B1 by the action of nitric oxide (II)

Nitric oxide II (NO) is a signaling molecule that has a wide range of physiological effects, including the regulation of gastrointestinal processes. The liver actively expresses the clinically significant transporters OATP1A2 and OATP1B1, which are involved in the influx of biologically active and medicinal substances. That is why it seems relevant to determine the pathways of regulation of hepatic transporters under the influence of NO. Aim. To study the effect of NO on the relative amount and expression of the transporters OATP1A2 and OATP1B1 in vitro in HepG2 cells. Materials and methods. The study was performed on a culture of HepG2 cells, which were cultured in 6-well plates at 37 °C and 5% CO2 in Dulbecco’s modified Eagle’s medium (DMEM) with a high glucose content (4500 mg/l) containing L-glutamine (4 mM), 10% fetal bovine serum, 100 U/ml penicillin and 100 mg/ml streptomycin (all components from Sigma-Aldrich, Germany). S-nitrosoglutathione (Sigma-Aldrich, Germany) was added to the culture medium at concentrations of 1, 10, 50, 100 and 500 µM, incubated for 24 and 72 hours. Water for injection (solvent) was added to control cells in an equivalent volume S-nitrosoglutathione). The relative amounts of OATP1A2 and OATP1B1 proteins were assessed by Western blot, and the expression of SLCO1A2 and SLCO1B1 by real-time PCR. The results of the study. In the course of this study, it was shown that the addition of S-nitrosoglutathione in the concentration range of 10-500 μM and exposure duration of 24 and 72 hours causes an increase in the intracellular level of nitric oxide metabolites, which indicates the adequacy of the use of this NO donor. At the same time, under the influence of NO, there was an increase in the relative amount of the studied transporters - OATP1A2 at an exposure period of 24 hours and S-nitrosoglutathione concentrations of 50 and 100 μM, OATP1B1-24 and 72 hours, at concentrations of 10-500 μM, a similar trend was noted for the expression genes SLCO1A2 and SLCO1B1. Conclusion. The NO donor - S-nitrosoglutathione causes an increase in the relative amount of OATP family transporters - OATP1A2 and OATP1B1, due to increased expression of the SLCO1A2 and SLCO1B1 genes, in vitro in HepG2 cells.

B-221 Combined RT-PCR and Whole Exome Sequencing Pharmacogenetic Testing in Polypharmacy Patient: A Case Report

Abstract Background Pharmacogenetics has become one of the main branches of Precision Medicine owing to its usefulness for patients’s optimal therapeutic management. Notwithstanding, pharmacogenetic testing results must be taken carefully, specially in multimorbidity patients with a variety of drugs prescribed. The aim of the present work is to introduce a combined RT-PCR and Whole Exome Sequencing Approach for pharmacogenetic testing in a patient with multiple drug-related adverse events. Case Background A 67 years old female was derived to our Clinical Chemistry Unit for pharmacogenetic testing due to multiple drug-related adverse events: nifedipine-voriconazole interaction, voriconazole-related neurological toxicity and moxifloxacin-related dizziness. Aditionally, she had been receiving morphine, corticoid for her reumatoid arthritis and antituberculous therapy (r isoniazid / pyrazinamide / rifampin and ethambutol). Methods Patient’s DNA was extracted from a blood sample and undergone by pharmacogenetic testing in two parallel ways: -A first genotyping assay was carried out using Taqman® OpenArray™ PGx Express 120 panel (ThermoFisher™), according to manufacturer’s instructions. -Simultaneusly, in order to cover possible copy number variants and SNPs not covered by our RT-PCR array, a whole exome sequencing run was performed on IlluminaTM NextSeq 1000. Sample library was prepared applying a custom GRCh38 pipeline. Results Relevant variants related to patient’s therapy found by RT-PCR are shown in table 1. SNPs genotyped by RT-PCR were confirmed by NGS. Moreover, whole exome sequencing revealed a deletion in exon 5 of SLCO1B1 gene, which corresponds to SLCO1B1*49 (loss of function); and some variants in NAT2 that may cause toxicity in antituberculous treatment (diplotype NAT2*6C/*7C). Conclusions In those challenging cases that involve multimorbidity and polypharmacy patients, pharmacogenetic testing must be approached taking into account variants that are not covered by the analytical method routinely used and the possibility of complement it with alternative proccedures.

Molecular tool for efficient breeding of DOMINANT Greenshell laying hens and significant refinement of phenotypic selection focused on eggshell color

In recent decades, interest in non-traditionally colored eggs has increased. For breeders, this market interest means breeding lines of laying hens that lay eggs of varied colors, such as the blue-green eggshells (Dominant Greenshell) in this study. This study presents the results of genotyping the polymorphism of the O locus responsible for shell coloration and photometric measurement of eggshell color based on the CIELAb system, which was carried out on the unique Czech breeding population Dominant Greenshell. The aim was to use a combination of phenotyping using the CIELab System method and genotyping of the O locus using the end-point PCR approach with the main focus on the accuracy of distinguishing shell color genotypes, streamlining the selection of dominant homozygotes in the O locus, optimizing this technology for the most efficient and cost-effective selection procedure in practical hen breeding. The optometric method was able to reliably distinguish only dominant and recessive phenotypes and eliminate from the population only undesirable recessive homozygotes with a white colored shell. The parameter a* (redness/greenness) from the CIELab color space turned out to be absolutely key for distinguishing dominant and recessive phenotypes. Using the CART methodology, a classification tree built on discriminating optometric characteristics a-blunt was obtained, however, for the group of desirable O/O homozygotes, the selection approach would result in incorrect genotyping of 31% of individuals. Therefore, a combined approach based on rapid and simple elimination of recessive homozygotes using phenotyping (CIELab photometric measurement) and molecular identification of the EAV-HP insertion in the SLCO1B3 gene in dominant phenotypes, regardless of color intensity affected by laying time/order, and allowing reliable elimination, has proven to be the most effective method to distinguish heterozygotes from the breeding population. The combination of optometric and molecular selection methods then leads to more efficient selection, reduction of overall selection costs. This process led to the stabilization of the breeding population within one generation and the achievement of a pure homozygous line with regard to eggshell color.

Thai pharmacogenomics database -2 (TPGxD-2) sequel to TPGxD-1, analyzing genetic variants in 26 non-VIPGx genes within the Thai population.

Next-generation sequencing (NGS) has transformed pharmacogenomics (PGx), enabling thorough profiling of pharmacogenes using computational methods and advancing personalized medicine. The Thai Pharmacogenomic Database-2 (TPGxD-2) analyzed 948 whole genome sequences, primarily from the Electricity Generating Authority of Thailand (EGAT) cohort. This study is an extension of the previous Thai Pharmacogenomic Database (TPGxD-1) and specifically focused on 26 non-very important pharmacogenes (VIPGx) genes. Variant calling was conducted using Sentieon (version 201808.08) following GATK's best workflow practices. We then annotated variant call format (VCF) files using Golden Helix VarSeq 2.5.0. Star allele analysis was performed with Stargazer v2.0.2, which called star alleles for 22 of 26 non-VIPGx genes. The variant analysis revealed a total of 14,529 variants in 26 non-VIPGx genes, with TBXAS1 had the highest number of variants (27%). Among the 14,529 variants, 2328 were novel (without rsID), with 87 identified as clinically relevant. We also found 56 known PGx variants among the known variants (n = 12,201), with UGT2B7 (19.64%), CYP1B1 (8.9%), SLCO2B1 (8.9%), and POR (8.9%) being the most common. We reported a high frequency of intermediate metabolizers (IMs) in CYP2F1 (34.6%) and CYP4A11 (8.6%), and a high frequency of decreased functional alleles in POR (53.9%) and SLCO1B3 (34.9%) genes. This study enhances our understanding of pharmacogenomic profiling of 26 non-VIPGx genes of notable clinical importance in the Thai population. However, further validation with additional computational and reference genotyping methods is necessary, and novel alleles identified in this study should undergo further orthogonal validation.

Association of SLCO1B1 gene variants with angiotensin-converting enzyme inhibitor-induced cough in a Pakistani hypertensive cohort.

Angiotensin-converting enzyme inhibitors (ACEIs) are prescribed for individuals with high cardiovascular (CV) risk; however, persistent cough limits the use of ACEIs in a large number of patients. The current study aimed to identify the genetic variants in the SLCO1B1 gene that might be associated with ACEI-related cough in a Pakistani hypertensive population. A prospective cohort study was conducted at a tertiary care hospital in Pakistan. A total of 74 patients who had been treated with ACEIs were recruited through a convenient sampling method. The study was approved by the Institutional Review Board & Ethics Committee of the Shifa International Hospital, Islamabad. Patients provided 2ml of blood for sequencing after signing informed consent. Partial gene sequencing of SLCO1B1 was carried out to find single nucleotide polymorphisms (SNPs) and haplotypes. It was found, through a structured questionnaire, that thirty-eight (38) patients experienced cough within 2weeks of ACEI administration and were considered as a case group (cough), and thirty-six (36) patients were considered as a control group (no cough). The incidence of cough was 51%. We found six different SNPs and 9 haplotypes in the partial gene sequences of SLCO1B1. Haplotype H4 was associated significantly with cough after adjusting for sex and smoking status. Other SNPs and haplotypes were not significantly associated with ACE-Is-induced cough. These findings emphasize the significance of SLCO1B1 genetic variants, specifically H4, as a potential predictor of ACEI-induced cough. It could be included in clinical practice as a possible risk factor for ACEI-induced cough once confirmed in larger clinical trials with bigger sample sizes. The replication of these findings in larger and more diverse populations is likely to contribute to the therapeutic use of ACEIs by predicting ACEI-induced cough.

Patterns of pharmacogenetic variation in nine biogeographic groups.

Frequencies of pharmacogenetic (PGx) variants are known to differ substantially across populations but much of the available PGx literature focuses on one or a few population groups, often defined in nonstandardized ways, or on a specific gene or variant. Guidelines produced by the Clinical Pharmacogenetic Implementation Consortium (CPIC) provide consistent methods of literature extraction, curation, and reporting, including comprehensive curation of allele frequency data across nine defined "biogeographic groups" from the PGx literature. We extracted data from 23 CPIC guidelines encompassing 19 genes to compare the sizes of the populations from each group and allele frequencies of altered function alleles across groups. The European group was the largest in the curated literature for 16 of the 19 genes, while the American and Oceanian groups were the smallest. Nearly 200 alleles were detected in nonreference groups that were not reported in the largest (reference) group. The genes CYP2B6 and CYP2C9 were more likely to have higher frequencies of altered function alleles in nonreference groups compared to the reference group, while the genes CYP4F2, DPYD, SLCO1B1, and UGT1A1 were less likely to have higher frequencies in nonreference groups. PGx allele frequencies and function differ substantially across nine biogeographic groups, all but two of which are underrepresented in available PGx data. Awareness of these differences and increased efforts to characterize the breadth of global PGx variation are needed to ensure that implementation of PGx-guided drug selection does not further widen existing health disparities among populations currently underrepresented in PGx data.

Allelic frequencies of polymorphism c.521T>C (rs4149056) favor preemptive SLCO1B1 genotyping in Armenia.

Statins represent an important pharmacological factor for the prevention of cardiovascular diseases but may also cause severe cases of myotoxicity. Numerous studies have described the association of the SLCO1B1 gene variant c.521C with statin-induced myopathy across different populations. This study aimed at evaluating the usefulness of preemptive SLCO1B1 genotyping in Armenia. A total of 202 Armenian patients referred to the Center of Medical Genetics and Primary Health Care in Yerevan for upper respiratory tract infection between January and May 2022 were included in this study. Genotyping for SLCO1B1 c.521T>C (rs4149056) was performed using a commercially available real-time PCR assay (RealFast™). In total, 3/202 (1.5 %) samples were C/C homozygotes and 52/202 (25.7 %) were T/C heterozygotes, associated with a high and increased risk for statin-induced myopathy, respectively. The SLCO1B1 c.521C allelic frequency was 14.4 %. The observed allele frequency of 14.4 % for thec.521C variant is slightly lower than frequencies reportedfrom Europe, but relatively high compared to Asianpopulations, suggesting that preemptive SLCO1B1 genotyping could be a useful approach for the reduction of statin-induced adverse effects in Armenia.

Causal association between serum bilirubin and ischemic stroke: multivariable Mendelian randomization.

Previous research has predominantly focused on total bilirubin levels without clearly distinguishing between direct and indirect bilirubin. In this study, the differences between these forms were examined, and their potential causal relationships with ischemic stroke were investigated. Two-sample multivariable Mendelian randomization (MVMR) analysis was employed, extracting summary data on bilirubin from the Korean Cancer Prevention Study-II (KCPS-II; n=159,844) and the Korean Genome and Epidemiology Study (KoGES; n=72,299). Data on ischemic stroke were obtained from BioBank Japan (BBJ; n=201,800). Colocalization analysis was performed, focusing on the UGT1A1, SLCO1B1, and SLCO1B3 genes, which are the primary loci associated with serum bilirubin levels. Crude 2-sample Mendelian randomization analysis revealed a significant negative association between total bilirubin levels and ischemic stroke. However, in MVMR analyses, only indirect bilirubin demonstrated a significant negative association with ischemic stroke (odds ratio, 0.76; 95% confidence interval, 0.59 to 0.98). Colocalization analysis did not identify a shared causal variant between the 3 genetic loci related to indirect bilirubin and the risk of ischemic stroke. Our study establishes a causal association between higher genetically determined levels of serum indirect bilirubin and reduced risk of ischemic stroke in an Asian population. Future research should include more in-depth analysis of shared genetic variants between indirect bilirubin and ischemic stroke.

The effect of SLCO1B1 gene polymorphism on the atorvastatin effectiveness in patients with cardiovascular diseases

The effect of SLCO1B1 gene polymorphism on the atorvastatin effectiveness in patients with cardiovascular diseases

Genetic alteration of SLCO1B3 defines constitutional indocyanine green excretory defect in patients who underwent hepatectomy.

Constitutional indocyanine green (ICG) excretory defects must be distinguished when assessing liver function. The absence of OATP1B3 expression due to homogenous alterations in the SLCO1B3 gene has been recently reported to induce ICG excretory defects; however, its association with the clinical examinations and the clinical implications of heterogeneous SLCO1B3 gene alteration remain unclear. OATP1B3 expression was evaluated in 49 patients who underwent hepatectomy after evaluation of the ICG retention rate at 15min (ICGR15) and technetium-99 m-galactosyl serum albumin (99mTc-GSA) hepatic scintigraphy. Additionally, alterations in SLCO1B3 were analyzed in patients without OATP1B3 expression. Subsequently, 59 patients who underwent hepatectomy for colorectal liver metastasis (CRLM) were analyzed. Of 49 patients, 6 (12%) had absent OATP1B3 expression. They had significantly higher ICGR15 value (74.7% vs. 23.5%; p<0.0001), better modified albumin-bilirubin (ALBI) grade (≤grade 2A, 100% vs. 42%; p=0.010), more normal 99mTc-GSA hepatic scintigraphy (100% vs. 28%; p=0.0003), and better pathological liver fibrosis (F0-1, 100% vs. 49%; p=0.027) compared to those with OATP1B3 expression. Three available frozen blocks of cases without OATP1B3 expression showed homozygous alterations in SLCO1B3. Of 59 patients with CRLM in normal liver background, five (8.5%) had heterozygous insertion in SLCO1B3, however they had no difference in ICGR15 values or other clinical findings compared to the other patients. Constitutional ICG excretory defects may be defined by the complete absence of OATP1B3 expression. The modified ALBI grade and 99mTc-GSA hepatic scintigraphy were useful for detecting constitutional ICG excretory defects.

Systematic review: genetic polymorphisms in the pharmacokinetics of high-dose methotrexate in pediatric acute lymphoblastic leukemia patients.

Variations in pharmacokinetic responses to high-dose methotrexate are essential for the prognosis and management of toxicity in the treatment of pediatric acute lymphoblastic leukemia (ALL) patients. This systematic review aimed to identify and evaluate genetic polymorphisms that are significantly associated with the pharmacokinetic parameters of methotrexate during the consolidation phase of pediatric ALL treatment. Using the Preferred Reporting Items for Systematic Reviews (PRISMA) guidelines, we systematically reviewed the literature from 2013 to 2023. The databases used were PubMed and Scopus. The outcomes of interest are the study design, patient characteristics, sample size, chemotherapy protocol utilized, pharmacokinetic parameters identified, and genetic polymorphisms implicated. We included 31 articles in the qualitative synthesis and found that the SLCO1B1, ABCB1, ABCC2, and MTHFR genes appear to play significant roles in MTX metabolism and clearance. Among these, variations in SLCO1B1 have the most significant and consistent impact on methotrexate clearance. These implicated variants may contribute to the precision and tailoring of HD-MTX treatment in pediatric ALL patients.

Inspecting the Allelic Frequency of SNPs of Solute Carrier Organic Anion Transporter Family Member 1B1(SLCO1B1) Gene in the Metabolic Pathway of Proposed Drugs in the Treatment of Pulmonary Tuberculosis in Iranian Population by Using Whole Exome Sequencing Technique

Inspecting the Allelic Frequency of SNPs of Solute Carrier Organic Anion Transporter Family Member 1B1(SLCO1B1) Gene in the Metabolic Pathway of Proposed Drugs in the Treatment of Pulmonary Tuberculosis in Iranian Population by Using Whole Exome Sequencing Technique

A pedigree analysis of Rotor hyperbilirubinemia combined with hepatitis B virus infection in a SLCO1B1 and SLCO1B3 gene mutations patient

BackgroundRotor syndrome (RS, OMIM#237450) is an extremely rare autosomal digenic recessive disorder characterized by mild non-hemolytic hereditary conjugated hyperbilirubinemia, caused by biallelic variation of SLCO1B1 and SLCO1B3 genes that resulted in OATP1B1/B3 dysfunction in the sinusoidal membrane leading to impaired bilirubin reuptake ability of hepatocytes. MethodsOne RS pedigree was recruited and clinical features were documented. Whole genome second-generation sequencing was used to screen candidate genes and mutations, Sanger sequencing confirmed predicted mutations. ResultsThis study detected a homozygous nonsense variant c.1738C > T (p.R580*) in the coding region of the SLCO1B1 (NM006446) gene in a family with RS and hepatitis B virus infection by Variants analysis and Sanger sequencing, and confirmed by Copy Number Variation (CNV) analysis and Long Range PCR that there was a homozygous insertion of intron 5 of the SLCO1B3 gene into intron 5 of long-interspersed element 1 (LINE1). A few cases of such haplotypes have been reported in East Asian populations. A hepatitis B virus infection with fatty liver disease was indicated by pathology, which revealed mild-moderate lobular inflammation, moderate lobular inflammation, moderate hepatocellular steatosis, and fibrosis stage 1–2 (NAS score: 4 points/S1-2) alterations. Heterozygotes carrying p.R580* and LINE1 insertions were also detected in family members (I1, I2, III2, III3), but they did not develop conjugated hyperbilirubinemia. ConclusionThe mutations may be the molecular genetic foundation for the presence of SLCO1B1 c.1738C > T(p.R580*) and SLCO1B3 (LINE1) in this RS pedigree.

Identification and Characterization of the miRNA Transcriptome Controlling Green Pigmentation of Chicken Eggshells

Green eggs are mainly caused by inserting an avian endogenous retrovirus (EVA-HP) fragment into the SLCO1B3 gene. Although the genotypes for this insertion allele are consistent, eggshell color (ESC) may vary after a peak laying period; light-colored eggs are undesired by consumers and farmers and result in financial loss, so it is necessary to resolve this problem. miRNAs are small non-coding RNAs that exert essential functions in animal development and diseases. However, the regulatory miRNAs and detailed molecular mechanisms regulating eggshell greenness remain unclear. In the present study, we determined the genotype of green-eggshell hens through the detection of a homozygous allele insertion in the SLCO1B3 gene. The shell gland epithelium was obtained from green-eggshell hens that produced white and green shell eggs to perform transcriptome sequencing and investigate the important regulatory mechanisms that influence the ESC. Approximately 921 miRNAs were expressed in these two groups, which included 587 known miRNAs and 334 novel miRNAs, among which 44 were differentially expressed. There were 22 miRNAs that were significantly upregulated in the green and white groups, respectively, which targeted hundreds of genes, including KIT, HMOX2, and several solute carrier family genes. A Gene Ontology enrichment analysis of the target genes showed that the differentially expressed miRNA-targeted genes mainly belonged to the functional categories of homophilic cell adhesion, gland development, the Wnt signaling pathway, and epithelial tube morphogenesis. A KEGG enrichment analysis showed that the Hedgehog signaling pathway was significantly transformed in this study. The current study provides an overview of the miRNA expression profiles and the interaction between the miRNAs and their target genes. It provides valuable insights into the molecular mechanisms underlying green eggshell pigmentation, screening more effective hens to produce stable green eggs and obtaining higher economic benefits.

Clinical characteristics and genetic analysis of four children with Rotor syndrome

To explore the characteristics of SLCO1B1/SLCO1B3 gene variants among children with Rotor syndrome (RS). Four children who were admitted to the Department of Hepatology of Hunan Children's Hospital between January 2019 and January 2022 were selected as the study subjects. Trio-whole exome sequencing was carried out for the four families, and gel electrophoresis was used to verify an insertional variant of long-interspersed element-1 (LINE-1). Genetic testing has identified three variants of the SLCO1B1 gene, including c.1738C>T (p.R580*), c.757C>T (p.R253*) and c.1622A>C (p.Q541P), and two variants of the SLCO1B3 gene, including c.481+22insLINE-1 and c.1747+1G>A among the children. Three of them were found to harbor homozygous variants of the SLCO1B1/SLCO1B3 genes, and one has harbored compound heterozygous variants. Sanger sequencing confirmed the existence of all variants, and gel electrophoresis has confirmed the existence of the LINE-1 insertional variant of about 6 kb within intron 6 of the SLCO1B3 gene in all children. The pathogenesis of the RS among the four children may be attributed to the variants of the SLCO1B1/SLCO1B3 genes. The LINE-1 insertion variant of the SLCO1B3 gene may be common among Chinese RS patients.

The impact of SLCO1B1 single nucleotide polymorphism and non-genetic factors on statin-induced myopathy

Abstract Funding Acknowledgements None. Background Statins, also known as HMG CoA Reductase Inhibitors, are a class of drugs considered the drug of choice for treating hypercholesterolemia. Statins are well tolerated; however, they may cause severe myopathy in 20% to 30% of patients, due to the individual variation regarding its efficacy and related adverse effects. Of these, comes the Single Nucleotide Polymorphism (SNP) T521C of the SLCO1B1 gene that encodes the protein involved in the trafficking of statins from the blood to hepatocytes which is called Organic Anion Transport Protein 1B1 (OATP1B1). The T521C single nucleotide polymorphism (SNP) results in a substitute of valine with alanine resulting in a decreased or lack of functional protein. Purpose The aim is to determine the frequency of the high-risk C allele and to define its impact on statin-induced myopathy in Syrian patients on statins. In addition to the non-genetic factors that may affect the ability to develop statin-induced myopathy. Methods This was an observational case-control study that had ethical approval from Damascus University (No.433/ 2020). The case group included 44 patients on statins who experienced myopathy, 18 patients who had increased creatinine kinase levels (CK), and 26 patients with normal CK levels, while the control group encompassed 56 patients who were taking statins and had no muscular adverse events. The DNA was extracted from each sample and then genotyped using standard sequencing of specific PCR products using a specific pair of primers. Results The age of patients in the case arm ranged between 27 and 84 years with an average ± SD of (58.2 ± 12.7 years), 70% of them were males. In comparison with (53.34 ± 12.4 years) in the control arm, 66% of them were males without a statistically significant differences (p=0.672, 0.057) respectively. The statin type and dose have a statistically non-significant effect, the average statin dose in the case arm and the control arm was 26.02 mg and 31.27 mg respectively (p=0.072). While the statin type treatment varied as 59% used atorvastatin and 39% used rosuvastatin in the case group compared with 71% used atorvastatin and 27% used rosuvastatin in the control group, without a statistically significant difference (p=0.252). The frequency of the C allele reaches 19.3% and is distributed in three genotypes: wild-type TT (68%), heterozygote TC (25%), and homozygote CC (7%) in the case arm, while it does not exceed 8% in the control arm with the absence of the CC genotype. Only a statistically significant difference was found in the frequency of the CC genotype between these two groups (p=0.047). Conclusion Our study is the first to identify the frequency of the 521T&amp;gt;C SNP of the SLCO1B1 gene in Syrian patients taking statins. Our data reveals a high prevalence of risk allele C in the patients who suffer from statin-induced myopathy with a statically significant difference from the control arm (p=0.026).

Utilizing Pharmacogenomic Data for a Safer Use of Statins among the Emirati Population.

Statins are the most prescribed lipid-lowering drugs worldwide. The associated adverse events, especially muscle symptoms, have been frequently reported despite their perceived safety. Three pharmacogenes, the solute carrier organic anion transporter family member 1B1 (SLCO1B1), ATP-binding cassette subfamily G member 2 (ABCG2), and cytochrome P450 2C9 (CYP2C9) are suggested as safety biomarkers for statins. The Clinical Pharmacogenomic Implementation Consortium (CPIC) issued clinical guidelines for statin use based on these three genes. The present study aimed to examine variants in these pharmacogenes to predict the safety of statin use among the Emirati population. Analyzing 242 whole exome sequencing data at the three genes enabled the determination of the frequencies of the single nucleotide polymorphisms (SNPs), annotating the haplotypes and the predicted functions of their proteins. In our cohort, 29.8% and 5.4% had SLCO1B1 decreased and poor function, respectively. The high frequency warns of the possibility of significant side effects of some statins and the importance of pharmacogenomic testing. We found a low frequency (6%) of the ABCG2:rs2231142 variant, which indicates the low probability of Emirati patients being recommended against higher rosuvastatin doses compared with other populations with higher frequencies of this variant. In contrast, we found high frequencies of the functionally impaired CYP2C9 alleles, which makes fluvastatin a less favorable choice. Among the sparse studies available, the present one demonstrates all SLCO1B1 and CYP2C9 function-impairing alleles among Emiratis. We highlighted how population-specific pharmacogenomic data can predict safer choices of statins, especially in understudied populations.

N6-methyladenosine-modified circSLCO1B3 promotes intrahepatic cholangiocarcinoma progression via regulating HOXC8 and PD-L1.

Refractoriness to surgical resection and chemotherapy makes intrahepatic cholangiocarcinoma (ICC) a fatal cancer of the digestive system with high mortality and poor prognosis. Important function invests circRNAs with tremendous potential in biomarkers and therapeutic targets. Nevertheless, it is still unknown how circRNAs contribute to the evolution of ICC. CircRNAs in paired ICC and adjacent tissues were screened by circRNAs sequencing. To explore the impact of circRNAs on ICC development, experiments involving gain and loss of function were conducted. Various experimental techniques, including quantitative real-time PCR (qPCR), western blotting, RNA immunoprecipitation (RIP), luciferase reporter assays, RNA pull-down, chromatin immunoprecipitation (ChIP), ubiquitination assays and so on were employed to identify the molecular regulatory role of circRNAs. Herein, we reported a new circRNA, which originates from exon 9 to exon 15 of the SLCO1B3 gene (named circSLCO1B3), orchestrated ICC progression by promoting tumor proliferation, metastasis and immune evasion. We found that the circSLCO1B3 gene was highly overexpressed in ICC tissues and related to lymphatic metastasis, tumor sizes, and tumor differentiation. Mechanically, circSLCO1B3 not only promoted ICC proliferation and metastasis via miR-502-5p/HOXC8/SMAD3 axis, but also eradicated anti-tumor immunity via suppressing ubiquitin-proteasome-dependent degradation of PD-L1 by E3 ubiquitin ligase SPOP. We further found that methyltransferase like 3 (METTL3) mediated the m6A methylation of circSLCO1B3 and stabilizes its expression. Our findings indicate that circSLCO1B3 is a potential prognostic marker and therapeutic target in ICC patients. Taken together, m6A-modified circSLCO1B3 was correlated with poor prognosis in ICC and promoted ICC progression not only by enhancing proliferation and metastasis via potentiating HOXC8 expression, but also by inducing immune evasion via antagonizing PD-L1 degradation. These results suggest that circSLCO1B3 is a potential prognostic marker and therapeutic target for ICC.