SMURF2 predisposes cancer cell toward ferroptosis in GPX4-independent manners by promoting GSTP1 degradation.

Ferroptosis is a non-apoptotic form of regulated cell death. Glutathione (GSH) peroxidase 4 (GPX4) and GSH-independent ferroptosis suppressor protein 1 (FSP1) have been identified as major defenses. Here, we uncover a protective mechanism mediated by GSH S-transferase P1 (GSTP1) by monitoring proteinomic dynamics during ferroptosis. Dramatic downregulation of GSTP1 is caused by SMURF2-mediated GSTP1 ubiquitination and degradation at early stages of ferroptosis. Intriguingly, GSTP1 acts in GPX4- and FSP1-independent manners by catalyzing GSH conjugation of 4-hydroxynonenal and detoxifying lipid hydroperoxides via selenium-independent GSH peroxidase activity. Genetic modulation of the SMURF2/GSTP1 axis or the pharmacological inhibition of GSTP1's catalytic activity sensitized tumor responses to Food and Drug Administration (FDA)-approved ferroptosis-inducing drugs both in vitro and in vivo. GSTP1 expression also confers resistance to immune checkpoint inhibitors by blunting ferroptosis. Collectively, these findings demonstrate a GPX4/FSP1-independent cellular defense mechanism against ferroptosis and suggest that targeting SMURF2/GSTP1 to sensitize cancer cells to ferroptosis has potential as an anticancer therapy.

Kindlin-2 maintains liver homeostasis by regulating GSTP1-OPN-mediated oxidative stress and inflammation in mice.

Hepatocyte plays a principal role in preserving integrity of the liver homeostasis. Our recent study demonstrated that Kindlin-2, a focal adhesion protein that activates integrins and regulates cell-extracellular matrix interactions, plays an important role in regulation of liver homeostasis by inhibiting inflammation pathway; however, the molecular mechanism of how Kindlin-2 KO activates inflammation is unknown. Here, we show that Kindlin-2 loss largely downregulates the antioxidant glutathione-S-transferase P1 in hepatocytes by promoting its ubiquitination and degradation via a mechanism involving protein-protein interaction. This causes overproduction of intracellular reactive oxygen species and excessive oxidative stress in hepatocytes. Kindlin-2 loss upregulates osteopontin in hepatocytes partially because of upregulation of reactive oxygen species and consequently stimulates overproduction of inflammatory cytokines and infiltration in liver. The molecular and histological deteriorations caused by Kindlin-2 deficiency are markedly reversed by systemic administration of an antioxidant N-acetylcysteine in mice. Taken together, Kindlin-2 plays a pivotal role in preserving integrity of liver function.

The TF/Nrf2/GSTP1 pathway is involved in stress-induced hepatocellular injury through ferroptosis.

Stress triggers a comprehensive pathophysiological cascade in organisms. However, there is a substantial gap in the research regarding the effects of stress on liver function. This study aimed to investigate the impact of restraint stress on hepatocellular damage and elucidate the underlying molecular mechanisms. An effective mouse restraint stress model was successfully developed, and liver function analysis was performed using laser speckle imaging, metabolomics and serum testing. Alterations in hepatocyte morphology were assessed using haematoxylin and eosin staining and transmission electron microscopy. Oxidative stress in hepatocytes was assessed using lipid reactive oxygen species and malondialdehyde. The methylation status and expression of GSTP1 were analysed using DNA sequencing and, real-time PCR, and the expression levels of GPX4, TF and Nrf2 were evaluated using real-time quantitative PCR, western blotting, and immunohistochemical staining. A stress-induced model was established in vitro by using dexamethasone-treated AML-12 cells. To investigate the underlying mechanisms, GSTP1 overexpression, small interfering RNA, ferroptosis and Nrf2 inhibitors were used. GSTP1 methylation contributes to stress-induced hepatocellular damage and dysfunction. GSTP1 is involved in ferroptosis-mediated hepatocellular injury induced by restraint stress via the TF/Nrf2 pathway. These findings suggest that stress-induced hepatocellular injury is associated with ferroptosis, which is regulated by TF/Nrf2/GSTP1.

Subcellular distribution and Nrf2/Keap1-interacting properties of Glutathione S-transferase P in hepatocellular carcinoma.

The oncogene and drug metabolism enzyme glutathione S-transferase P (GSTP) is also a GSH-dependent chaperone of signal transduction and transcriptional proteins with key role in liver carcinogenesis. In this study, we explored this role of GSTP in hepatocellular carcinoma (HCC) investigating the possible interaction of this protein with one of its transcription factor and metronome of the cancer cell redox, namely the nuclear factor erythroid 2-related factor 2 (Nrf2). Expression, cellular distribution, and function as glutathionylation factor of GSTP1-1 isoform were investigated in the mouse model of N-nitrosodiethylamine (DEN)-induced HCC and in vitro in human HCC cell lines. The physical and functional interaction of GSTP protein with Nrf2 and Keap1 were investigated by immunoprecipitation and gene manipulation experiments. GSTP protein increased its liver expression, enzymatic activity and nuclear levels during DEN-induced tumor development in mice; protein glutathionylation (PSSG) was increased in the tumor masses. Higher levels and a preferential nuclear localization of GSTP protein were also observed in HepG2 and Huh-7 hepatocarcinoma cells compared to HepaRG non-cancerous cells, along with increased basal and Ebselen-stimulated levels of free GSH and PSSG. GSTP activity inhibition with the GSH analogue EZT induced apoptotic cell death in HCC cells. Hepatic Nrf2 and c-Jun, two transcription factors involved in GSTP expression and GSH biosynthesis, were induced in DEN-HCC compared to control animals; the Nrf2 inhibitory proteins Keap1 and ß-TrCP also increased and oligomeric forms of GSTP co-immunoprecipitated with both Nrf2 and Keap1. Nrf2 nuclear translocation and ß-TrCP expression also increased in HCC cells, and GSTP transfection in HepaRG cells induced Nrf2 activation. In conclusion, GSTP expression and subcellular distribution are modified in HCC cells and apparently contribute to the GSH-dependent reprogramming of the cellular redox in this type of cancer directly influencing the transcriptional system Nrf2/Keap1.

Imaging macular carotenoids and their related proteins in the human retina with confocal resonance Raman and fluorescence microscopy.

Lutein and zeaxanthin are highly concentrated at the central region of the human retina, forming a distinct yellow spot known as the macula lutea. The delivery and retention of the macular pigment carotenoids in the macula lutea involves many proteins, but their exact roles remain incompletely understood. In our study, we examined the distribution of the twelve known macular carotenoid-related proteins within the human macula and the underlying retinal pigment epithelium (RPE) using both fluorescence and Raman modes on our confocal resonance Raman microscope. Additionally, we assessed protein and gene expression through Western blot analysis and a single-cell RNA sequencing database. Our findings revealed that GSTP1, BCO2, and Aster-B exhibited distribution patterns similar to the macular carotenoids, with higher expression levels within the macular region compared to the periphery, while SR-BI and ABCA1 did not exhibit specific distribution patterns within the macula or RPE. Interestingly, LIPC, SR-BI's partner, accumulated specifically in the sub-foveal RPE. All three of these carotenoid transport proteins were found to be highly expressed in the RPE. These results offer valuable insights into the roles these proteins play in the formation of the macula lutea.

Ile105Val polymorphism in the GSTP1 gene is associated with susceptibility to acute myeloid leukemia: an updated systematic review and meta-analysis.

BACKGROUND AND OBJECTIVE: Several genetic variations are associated with acute myeloid leukemia (AML) susceptibility, including the GSTP1 Ile105Val polymorphism. Even with the existing meta-analysis conducted on the topic, no consensus has been reached since none of the studies available performed in-depth data analysis. Hence, we performed an updated systematic review and meta-analysis in this paper to obtain more precise estimates. MATERIALS AND METHODS: We searched various databases and calculated the odds ratio (OR) and 95% confidence interval (CI) to examine whether the GSTP1 Ile105Val polymorphism is associated with AML susceptibility. Further statistical analysis was also done to obtain more accurate and reliable findings. RESULTS: A total of 15 studies are included in the systematic review, but only 9 were included in the meta-analysis due to the studies deviating from the Hardy-Weinberg equilibrium. The analysis showed significantly increased susceptibility to AML in the allelic, co-dominant, and recessive models. Furthermore, subgroup analysis noted increased AML susceptibility in the non-Asian population. Comparing the proportions of the genotypes and alleles showed a significantly higher proportion of the Val/Val genotype and Val allele in the non-Asian cohort. CONCLUSION: The GSTP1 Ile105Val polymorphism is significantly associated with AML susceptibility, especially among non-Asians. Further investigation should be performed to strengthen the current results.

GSTP1 is a negative regulator of MAVS in the antiviral signaling against SVCV infection.

Glutathione S-transferase P1 (GSTP1), the most ubiquitous member of the GST superfamily, plays vital roles in the detoxification, antioxidant defense, and modulation of inflammatory responses. However, limited studies have been conducted on the function of GSTP1 in antiviral innate immunity. In this study, we have cloned the homolog of GSTP1 in triploid hybrid crucian carp (3nGSTP1) and investigated its regulatory role in the interferon signaling pathway. The open reading frame of 3nGSTP1 is composed of 627 nucleotides, encoding 209 amino acids. In response to spring viremia of carp virus (SVCV) infection, the mRNA level of 3nGSTP1 was up-regulated in the liver, kidney, and caudal fin cell lines (3 nF C) of triploid fish. The knockdown of 3nGSTP1 in 3 nF C improved host cell's antiviral capacity and attenuated SVCV replication. Additionally, overexpression of 3nGSTP1 inhibited the activation of IFN promoters induced by SVCV infection, poly (I:C) stimulation, or the RLR signaling factors. The co-immunoprecipitation assays further revealed that 3nGSTP1 interacts with 3nMAVS. In addition, 3nGSTP1 dose-dependently inhibited 3nMAVS-mediated antiviral activity and reduced 3nMAVS protein level. Mechanistically, 3nGSTP1 promoted ubiquitin-proteasome degradation of MAVS by promoting its K48-linked polyubiquitination. To conclude, our results indicate that GSTP1 acts as a novel inhibitor of MAVS, which negatively regulates the IFN signaling.

Docetaxel-induced severe neuropathy, a case of breast cancer with GTSP1 polymorphism.

INTRODUCTION: Breast cancer, the most prevalent cancer among women, often requires chemotherapy with docetaxel being a key agent. However, docetaxel-inducted peripheral neuropathy (DIPN) can adversely impact patients' quality of life. This case discusses an unusual instance of severe DIPN leading to wheelchair dependence in a 35-years old woman undergoing neoadjuvant treatment for locally advanced breast cancer. CASE: Following anthracycline and cyclophosphamide cycles without neurological symptoms, docetaxel administration resulted in progressive neuropathy. Despite dose reduction, the patient developed severe paraesthesias, foot weakness, and eventually wheelchair dependence. MANAGEMENT AND OUTCOME: Docetaxel's microtubule-stabilizing mechanism, vital for cell division, may disrupt axonal structures, causing sensory and motor neuropathy. While rare, severe motor neuropathy, leading to wheelchair dependence, poses a significant challenge. The frequency of DIPN varies, with docetaxel exhibiting lower neuropathy rates than other taxanes. Risk factors include age, diabetes mellitus, cumulative dose, and genetic polymorphisms in GSTP1 and ABCB1. In our case, despite the patient being young, fit and without diabetes, severe DIPN occured, suggesting a potential genetic predisposition. Genetic variations, such as GSTP1 polymorphisms have been associated with DIPN. Our patient carried GSTP1 (I1e105Val) mutations, emphasizing the need for further research to establish their role as risk factors. DISCUSSION: This case underscores the importance of recognizing severe DIPN, even in atypical patient profiles. Genetic factors, like GSTP1 polymorphisms, may contribute to DIPN risk. Large-scale studies are crucial to establishing the significance of these genetic variations in DIPN susceptibility.

Risk of Cardiovascular Complications Among Type 2 Diabetes Mellitus Patients with GSTP1 Genetic Polymorphism: A Nested Case-Control Study and Docking Studies.

The genetic alteration in the antioxidant gene Glutathione-S-Transferases Pi 1 (GSTP1) namely GSTP1*IIe105Val (rs1695) and GSTP1*Ala114Val (rs1138272) changes the individual susceptibility to cardiovascular disease (CVD) and type 2 diabetes mellitus (T2DM) by altering the substrate binding and catalytic activity. This study aims to investigate the association of GSTP1 rs1695 and rs1138272 polymorphism with CVD development in T2DM patients. Genotyping was performed with 400 study participants-group I: control; group II: T2DM; group III: CVD; and group IV: T2DM/CVD [n = 100 each] by PCR-RFLP. The rs1695 and rs1138272 polymorphism were docked against NPACT and NUBBE database and virtually screened using glide. The study reported that rs1695 polymorphism was associated with T2DM risk under dominant and allelic genetic models [OR = 1.97(1.08-3.59) p = 0.02 and OR = 1.79(1.20-2.66) p = 0.003, respectively]. The val/val genotype, dominant, recessive model, and T allelic genetic model were associated with increased CVD risk [OR = 4.15(1.97-8.73) p = < 0.01; OR = 3.16(1.65-6.04) p = < 0.01; OR = 3.47(1.91-6.31) p = < 0.01; and OR = 2.94(1.95-4.43) p = < 0.01, respectively]. In contrast, rs1695 polymorphism was not associated with CVD development among patients with T2DM. In rs1138272, the wild genotype was only detected and neither heterozygous nor val/val genotype was observed. The docking analysis revealed that the Ile105Val mutation plays a significant role in altering the GSTP1 capacity compared to the Ala115Val mutation. This suggests that the Ile105Val mutation has a greater impact on the protein's structure, function, or susceptibility to diseases compared to the Ala115Val mutation. In summary, genetic alteration in GSTP1 rs1695 potentially contributes to an increased risk of T2DM and CVD.

Involvement of GSTP1 in low dose radiation-induced apoptosis in GM12878 cells.

BACKGROUND: Low-dose ionizing radiation-induced protection and damage are of great significance among radiation workers. We aimed to study the role of glutathione S-transferase Pi (GSTP1) in low-dose ionizing radiation damage and clarify the impact of ionizing radiation on the biological activities of cells. RESULTS: In this study, we collected peripheral blood samples from healthy adults and workers engaged in radiation and radiotherapy and detected the expression of GSTP1 by qPCR. We utilized γ-rays emitted from uranium tailings as a radiation source, with a dose rate of 14 µGy/h. GM12878 cells subjected to this radiation for 7, 14, 21, and 28 days received total doses of 2.4, 4.7, 7.1, and 9.4 mGy, respectively. Subsequent analyses, including flow cytometry, MTS, and other assays, were performed to assess the ionizing radiation's effects on cellular biological functions. In peripheral blood samples collected from healthy adults and radiologic technologist working in a hospital, we observed a decreased expression of GSTP1 mRNA in radiation personnel compared to the healthy controls. In cultured GM12878 cells exposed to low-dose ionizing radiation from uranium tailings, we noted significant changes in cell morphology, suppression of proliferation, delay in cell cycle progression, and increased apoptosis. These effects were partially reversed by overexpression of GSTP1. Moreover, low-dose ionizing radiation increased GSTP1 gene methylation and downregulated GSTP1 expression. Furthermore, low-dose ionizing radiation affected the expression of GSTP1-related signaling molecules. CONCLUSIONS: This study shows that low-dose ionizing radiation damages GM12878 cells and affects their proliferation, cell cycle progression, and apoptosis. In addition, GSTP1 plays a modulating role under low-dose ionizing radiation damage conditions. Low-dose ionizing radiation affects the expression of Nrf2, JNK, and other signaling molecules through GSTP1.

Design, Synthesis, Computational Studies, and Anti-Proliferative Evaluation of Novel Ethacrynic Acid Derivatives Containing Nitrogen Heterocycle, Urea, and Thiourea Moieties as Anticancer Agents.

In the present work, the synthesis of new ethacrynic acid (EA) derivatives containing nitrogen heterocyclic, urea, or thiourea moieties via efficient and practical synthetic procedures was reported. The synthesised compounds were screened for their anti-proliferative activity against two different cancer cell lines, namely, HL60 (promyelocytic leukaemia) and HCT116 (human colon carcinoma). The results of the in vitro tests reveal that compounds 1-3, 10, 16(a-c), and 17 exhibit potent anti-proliferative activity against the HL60 cell line, with values of the percentage of cell viability ranging from 20 to 35% at 1 µM of the drug and IC50 values between 2.37 µM and 0.86 µM. Compounds 2 and 10 showed a very interesting anti-proliferative activity of 28 and 48% at 1 µM, respectively, against HCT116. Two PyTAP-based fluorescent EA analogues were also synthesised and tested, showing good anti-proliferative activity. A test on the drug-likeness properties in silico of all the synthetised compounds was performed in order to understand the mechanism of action of the most active compounds. A molecular docking study was conducted on two human proteins, namely, glutathione S-transferase P1-1 (pdb:2GSS) and caspase-3 (pdb:4AU8) as target enzymes. The docking results show that compounds 2 and 3 exhibit significant binding modes with these enzymes. This finding provides a potential strategy towards developing anticancer agents, and most of the synthesised and newly designed compounds show good drug-like properties.

Vibratome technique revealed initial carcinogenic changes that induce GST-P+ single hepatocytes and minifoci in rat liver.

The drastic initial carcinogenic changes that induce single hepatocytes and minifoci positive for GST-P (a specific biomarker of foci and nodules) identified previously in rat livers (K. Satoh, Life Sci. 2018) require elucidation. Notably, after animals were administered benzyl isothiocyanate (BITC, anti-cancer phytochemical, 0.5% by wt) in their basal diet, immunocytochemical staining of vibratome-prepared liver specimens for GST-P revealed that the canalicular networks and bile ducts of the animal livers were heavily and finely stained for GST-P even though the biomarker is a cytosolic enzyme. In addition, the mean diameter of the canaliculi was greatly enlarged. The results thus indicate that GST-P was rapidly synthesized in all hepatocytes but rapidly excreted into bile. Similar results were obtained with animals administered dietary AAF carcinogen (0.04%). The biliary excretion of GST-P was detectable not only in all hepatocytes but also within minifoci, foci and nodules. A new initiation model was therefore proposed assuming that GST-P+ single hepatocytes are formed after injury to canaliculi by carcinogens to decrease the excretion of GST-P from hepatocytes. The key findings from this study and the biomarker analysis using a vibratome technique might help elucidate the 'unknowable' mechanism of cancer initiation in rat chemical carcinogenesis.

Absence of GSTT1 and polymorphisms in GSTP1 and TP53 are associated with the incidence of acne vulgaris.

BACKGROUNDS: Acne vulgaris is a chronic inflammatory skin disease of the pilosebaceous unit affecting most teenagers and numerous adults throughout the world. The present study was designed to assess the association of the presence or absence of GSTM1, GSTT1, and single nucleotide polymorphisms rs1695 in GSTP1 and rs1042522 in TP53 gene with acne vulgaris. METHODS: The cross-sectional case-control study was conducted at the Institute of Zoology from May 2020 to March 2021 and included acne vulgaris patients (N = 100) and controls (N = 100) enrolled in Dera Ghazi Khan district, Pakistan. Multiplex and tetra-primer amplification refractory mutation system-polymerase chain reactions were applied to investigate the genotype in analyzed genes. The association of rs1695 and rs1042522 with acne vulgaris was studied either individually or in various combinations with GATM1 and T1. RESULTS: A significant association of absence of GSTT1 and mutant genotype at rs1695 (GG) and at rs1042522 (CC) in GSTP1 and TP53, respectively, was found to be associated with acne vulgaris in enrolled subjects. Subjects aged 10-25 years and smokers were more susceptible to acne vulgaris. CONCLUSION: Our results suggest that genotypes of glutathione S-transferases (GSTs) and TP53 are involved in protection against oxidative stress and may influence disease progression in acne vulgaris.

A CRAF/glutathione-S-transferase P1 complex sustains autocrine growth of cancers with KRAS and BRAF mutations.

The Ras/RAF/MEK/ERK pathway is an essential signaling cascade for various refractory cancers, such as those with mutant KRAS (mKRAS) and BRAF (mBRAF). However, there are unsolved ambiguities underlying mechanisms for this growth signaling thereby creating therapeutic complications. This study shows that a vital component of the pathway CRAF is directly impacted by an end product of the cascade, glutathione transferases (GST) P1 (GSTP1), driving a previously unrecognized autocrine cycle that sustains proliferation of mKRAS and mBRAF cancer cells, independent of oncogenic stimuli. The CRAF interaction with GSTP1 occurs at its N-terminal regulatory domain, CR1 motif, resulting in its stabilization, enhanced dimerization, and augmented catalytic activity. Consistent with the autocrine cycle scheme, silencing GSTP1 brought about significant suppression of proliferation of mKRAS and mBRAF cells in vitro and suppressed tumorigenesis of the xenografted mKRAS tumor in vivo. GSTP1 knockout mice showed significantly impaired carcinogenesis of mKRAS colon cancer. Consequently, hindering the autocrine loop by targeting CRAF/GSTP1 interactions should provide innovative therapeutic modalities for these cancers.

Study of the Methylation of Bovine GSTP1 Gene under the Influence of Pesticide Mospilan 20SP Alone and in Combination with Pesticide Orius 25EW.

DNA methylation, one of the most studied epigenetic mechanisms, when present in the promoter region of genes, causes inhibition of gene expression, and conversely, hypomethylation of these regions enables gene expression. DNA methylation is susceptible to nutritional and environmental influences, and undesirable alterations in methylation patterns manifested in changes in the expression of relevant genes can lead to pathological consequences. In the present work, we studied the methylation status of the bovine GSTP1 gene under the influence of pesticide Mospilan 20SP alone and in combination with pesticide Orius 25EW in in vitro proliferating bovine lymphocytes. We employed methylation-specific PCR, and when studying the effect of pesticide combinations, we also used its real-time version followed by a melting procedure. Our results showed that Mospilan 20SP alone at 5, 25, 50, and 100 µg.ml-1 and 5, 10, 25, and 50 µg.ml-1 for the last 4 and 24 hours of culture with in vitro proliferating bovine lymphocytes, respectively, did not induce methylation of the bovine GSTP1 gene. The same results were revealed when studying the effect of the combination of the pesticides added to the lymphocyte cultures for the last 24 hours of cultivation in the following amounts: 1.25, 2.5, 5, 10, and 25 µg.ml-1 of Mospilan 20SP and 1.5, 3, 6, 15, and 30 µg.ml-1 of Orius 25EW. We have also revealed that the less laborious real-time MSP followed by a melting procedure may replace MSP for studying the methylation status of the GSTP1 gene.

Association of genetic polymorphisms with mercapturic acids in the urine of young healthy subjects before and after exposure to outdoor air pollution.

We aimed to identify the relationship between variations in metabolic genes and human urinary changes in mercapturic acids (MAs), including CEMA, HMPMA, SPMA, HPMA and HEMA, before and after air pollution exposure. Genotype detection for 47 relevant single nucleotide polymorphisms (SNPs) collected by literature research was performed. Five MAs expression levels in the urinary samples of 50 young healthy individuals with short-term exposure to clean, polluted and purified air at five time points were detected by targeted online solid-phase extraction liquid chromatography tandem mass spectrometry (SPE-LC-MS/MS), followed with associations of SNPs with MAs changes. Difference in MAs between polluted and clean/purified air was significantly associated with 21 SNPs mapped into 9 genes. Five SNPs in GSTP1 showed the most prominent association with the changes in SPMA expression, indicating that those SNPs in GSTP1 and SPMA might serve as biomarkers for susceptibility and the prognosis of lung cancer.

Influence of GSTP1 rs1695 polymorphism on survival in male patients' amyotrophic lateral sclerosis: a genetic association study in Brazilian population.

BACKGROUND: Glutathione S-transferase Pi (GSTP1) enzyme has a major antioxidant effect on the central nervous system (CNS), where it acts against oxidative damage, an established risk factor for amyotrophic lateral sclerosis (ALS). Hence, the purpose of this study was to evaluate a possible relationship between GSTP1 rs1695 polymorphism and the survival rate of male ALS patients, which is the gender more affected by the disease. METHODS AND RESULTS: A case-control study was performed with 56 male ALS patients and 70 healthy male individuals from Midwestern Brazil, which were age-adjusted. GSTP1 rs1695 polymorphism molecular analysis was carried out with restriction fragment length polymorphism. The relationship between ALS patients and GSTP1 rs1695 polymorphism was analyzed using cumulative survival rate as the major outcome, where differences in survival were evaluated through the log-rank test. Our results revealed that mutant genotype (G/G) did not influence the cumulative survival rate of male ALS patients regarding the age of diagnosis (p = 0.5) and time from symptom to diagnosis (p = 0.3). On the other hand, mutant carriers exhibited a significant survival of fewer than 25 months compared to A/A and A/G genotypes that survive more than 100 months (p = 7-E10) in comparison with symptom onset to outcome (p = 0.00006). CONCLUSIONS: In summary, our findings revealed that mutant genotype carriers' male patients had a reduced lifetime, which probably may be resulted from oxidative stress exposure in CNS.

Analysis of the GSTP1 rs1695 polymorphism association with the development of asthma and phenotypic manifestations.

OBJECTIVE: The development of asthma and its related phenotypes is most likely due to the polymorphism of the so-called modifier genes. The goal of this study was to evaluate the polymorphic locus rs1695 of the GSTP1 gene association with risk factors for developing asthma and its phenotypic manifestations. METHODS: This case-control study involved 164 patients with confirmed asthma diagnosis and 147 age- and sex-matched controls. Patients were divided into two groups: with (n = 121) and without complications (n = 43). Among asthmatic patients, 34 manifested hypersensitivity to household allergens. The GSTP1 rs1695 polymorphism was genotyped using the technique of polymerase chain reaction-restriction fragment length polymorphism. RESULTS: There were no differences between patients and controls in allelic or genotype frequencies of polymorphic locus rs1695 of the GSTP1 gene. However, the frequency of the A/A genotype in the patient group with complications was significantly lower than that in complication-free patients (p = 0.040), while the frequency of the G allele was higher in patients with complications (p = 0.030). The frequency of the A/A genotype was decreased in the patient group with an allergic reaction to household allergens in comparison with controls (p = 0.037). CONCLUSION: These results suggest that the carriage of the A/A genotype of polymorphic locus rs1695 of the GSTP1 gene is a protective factor in the development of complications and an allergic reaction to house allergens among asthmatics, while the carriage of the G allele is associated with an increased risk for asthma complications.

Sesquiterpene lactones from Elephantopus scaber exhibit cytotoxic effects on glioma cells by targeting GSTP1.

Sesquiterpene lactones possess excellent anti-tumor activity in multiple cancer cell lines, including glioma, the most common type of malignant brain tumor with high mortality. However, the detailed mechanism of this type of constituent, especially the potential target for anti-glioma effect, is still unclear. Here, we collected 52 sesquiterpene lactones from Elephantopus scaber Linn. for network pharmacology analysis. The results demonstrated that the targets of the active components were markedly enriched on the pathways in cancer, which were closely related to cell proliferation regulation. Next, the Gene Expression Omnibus (GEO) and DisGeNET were analyzed by bioinformatics, and 429 glioma-related targets were obtained. Furtherly, 34 common targets of compounds and glioma were revealed, and they were significantly enriched in MAPK signaling pathway. Subsequently, we constructed a common target-compound network, and glutathione S-transferase Pi 1 (GSTP1) had the highest degree value, which explained its significance in the network. Therefore, we speculated that the compounds might exert an anti-glioma effect by targeting GSTP1. To verify the above results, we obtained part of sesquiterpene lactones isolated from E. scaber in our laboratory and evaluated their activities against glioma U87 cells. Among these sesquiterpene lactones (1-27), compounds 1 (elephantopinolide A), 2 (cis-scabertopin) and 3 (elephantopinolide F) exhibited the strongest inhibitory effect, and the IC50 values were 4.22 ± 0.14 µM, 4.28 ± 0.21 µM and 1.79 ± 0.24 µM, respectively. The results from molecular docking, cellular thermal shift assay (CETSA), as well as RT-PCR and Western blot analysis suggested that the compounds exerted an inhibitory effect by targeting GSTP1. Meanwhile, the compounds also activated JNK/STAT3 signaling pathway. Furthermore, we found that 1, 2 and 3 could suppress cell proliferation and also induce mitochondrial dysfunction as well as oxidative stress, eventually leading to cellular apoptosis. Taken together, this study revealed that sesquiterpene lactones from E. scaber could be a promising therapeutic strategy for the treatment of glioma by targeting GSTP1.

Allele and genotype frequencies of CYP3A4, CYP3A5, CYP3A7, and GSTP1 gene polymorphisms among mainland Tibetan, Mongolian, Uyghur, and Han Chinese populations.

Over 50% prescribed drugs are metabolised by cytochrome P450 3A (CYP3A) and glutathione S-transferase pi (GSTP1) adds a glutathione to the oxidative products by CYP3A, which increases the hydrophilic property of metabolites and facilitates the excretion. Single nucleotide polymorphisms (SNPs) of CYP3A and GSTP1 show a diverse allele and genotype frequencies distribution among the world populations. The present study aimed to investigate the genotype and allele frequency distribution patterns of CYP3A4, CYP3A5, CYP3A7 and GSTP1 polymorphisms among healthy participants in mainland Tibetan, Mongolian, Uyghur, and Han Chinese populations. Blood samples were collected from 842 unrelated healthy subjects (323 Tibetan, 134 Mongolian, 162 Uyghur, and 223 Han) for genotyping analysis. Variant allele frequencies of CYP3A4 rs2242480, CYP3A5 rs776746, CYP3A7 rs2257401, and GSTP1 Ile105Val were observed in Han (0.253, 0.686, 0.312 and 0.188), Tibetan (0.186, 0.819, 0.192 and 0.173), Mongolian (0.198, 0.784, 0.228 and 0.235) and Uyghur (0.179, 0.858, 0.182 and 0.250) respectively. The allele frequency of CYP3A7*1C in Uyghur (0.019) was higher than that in Tibetan (0.002, p < 0.01). There was a strong linkage disequilibrium between CYP3A4 rs2242480, CYP3A5 rs776746, and CYP3A7 rs2257401 among the four ethnic groups. The results might be useful for the precise medication in the Chinese populations.