Resistance-related Protein Research Articles

Identification of Quantitative Trait Loci and Analysis of Novel Candidate Genes for Resistance to False Smut of Rice Based on SSR Molecular Markers

Rice false smut (RFS), an emerging disease caused by the fungus Ustilaginoidea virens (Cooke), reduces rice grain yield and quality in rice-planting regions worldwide. The identification of the genes or quantitative trait loci (QTLs) associated with RFS resistance is vital to resistance breeding and the mitigation of RFS damage. In this study, RFS resistance QTLs were located in the resistant variety IR77298-14-1-2::IRGC117374-1. A total of 4 RFS resistance QTLs were detected on rice chromosomes 1, 3, 5, and 12 in the F2 and F4 mapping populations using 119 polymorphic simple sequence repeat (SSR) molecular markers. Of these QTLs, qRFS3.01 and qRFS12.01-1 were repeatedly detected in both populations. Interestingly, QTL qRFS3.01 on chromosome 3 is a novel resistance locus that exhibited the largest phenotypic effect. These results suggest that SSR markers linked to qRFS3.01 are valuable for marker-assisted breeding for RFS resistance in rice. The prediction of putative candidate genes within qRFS3.01 revealed three resistance-related proteins containing an F-box domain, Myb-like DNA-binding domain, and kinase protein. In summary, our findings provide new QTLs/genes for resistance to RFS and will promote rice disease resistance through molecular-marker-assisted breeding.

Expression of ABCB1, ABCC1, and LRP in Mesenchymal Stem Cells from Human Amniotic Fluid and Bone Marrow in Culture-Effects of In Vitro Osteogenic and Adipogenic Differentiation.

Mesenchymal stem cells (MSCs) are multipotent cells with the potential to differentiate into various lineages. They have also the potential to protect themselves against harmful stimuli to maintain their functional integrity. Drug resistance-related transporters such as ABCB1 (P-glycoprotein; P-gp), ABCC1 (MRP1; multidrug resistance-related Protein 1), and LRP (lung resistance protein) may protect MSCs against toxic substances such as chemotherapeutic agents. This study evaluated ABCB1, ABCC1, and LRP before and after the differentiation of MSCs derived from human amniotic fluid (AF) and bone marrow (BM). P-gp expression in both AFMSCs and BMMSCs was analyzed by immunocytochemistry, and pump function was analyzed by cell viability assay with doxorubicin (DOX) and Rhodamine 123 (Rh 123) dye exclusion. ABCB1, ABCC1, and LRP gene expression was determined by RT-PCR both before and after osteogenic and adipogenic differentiation. The MES-SA/DX5 cell line was used as a model of resistance to DOX and the overexpression of P-gp. Both AFMSCs and BMMSCs displayed a high P-gp expression, although lower than MES-SA/DX5 control cells. It was shown that both, undifferentiated AFMSCs and BMMSCs, have high cell viability in response to DOX, similar to the MES-SA/DX5 lineage. ABCB1 was less expressed in BM than in AFMSCs in undifferentiated samples, while no differences were observed in the expression of ABCC1 and LRP. AFMSCs showed an increase in ABCB1 after osteogenic differentiation, whereas BMMSCs exhibited lower ABCB1 and ABCC1 expression after osteogenic and adipogenic differentiation. The findings suggest that ABCB1, ABCC1, and LRP gene expression in AFMSCs and BMMSCs is influenced by differentiation processes and further support the concept that these transporters modulate MSC differentiation in a cell source-dependent way.

Ginsenoside RG3 Synergizes With STING Agonist to Reverse Cisplatin Resistance in Gastric Cancer.

This study investigates the synergistic inhibitory effects of combining the stimulator of interferon genes (STING) agonist cyclic diadenylate monophosphate (c-di-AMP) and ginsenoside RG3 on cisplatin (DDP)-resistant gastric cancer (GC) cells. The objective is to identify novel therapeutic targets and offers insights for the clinical management of DDP resistance. Various techniques were employed, including western blot, MTT assay, colony formation assay, scratch assay, transwell assay, tubule formation assay, flow cytometry, Hoechst 33342 fluorescence staining, and invivo experiments, to investigate the potential mechanisms and effects of the combined application of the STING agonist and ginsenoside RG3 in reversing cisplatin resistance in gastric cancer. The combination markedly suppressed key malignant behaviors, including proliferation, migration, invasion, and angiogenesis of SGC-7901/DDP cells. Additionally, this treatment inhibited the epithelial-mesenchymal transition (EMT) process and stem cell-like characteristics of SGC-7901/DDP cells, while downregulating the expression of resistance-related proteins. The STING agonist effectively suppresses the growth and proliferation of gastric cancer cells. Ginsenoside RG3, well-documented for its multifaceted properties, including antioxidant, anti-aging, and anti-cancer effects, is widely used in cancer treatment and in managing chemotherapy-related side effects. Furthermore, RG3 enhances anti-tumor immunity by regulating signal transduction. This study comprehensively evaluated the efficacy of the STING agonist and RG3 combination through invitro and invivo experiments, demonstrating significant inhibition of malignant progression and reversal of drug resistance in gastric cancer. These findings offer a robust theoretical foundation for clinical applications and highlight new therapeutic targets for future research.

A Near-Infrared II Luminogen with a Photothermal Effect toward Tumor Drug Resistance Reversal.

Multidrug resistance of tumor cells has greatly limited the chemotherapy effect. The development of reliable strategies to deal with tumor multidrug resistance is highly desirable for tumor therapy. In this work, a near-infrared II (NIR II) luminogen was rationally designed and prepared, which could act as a photothermal reagent to reverse the drug resistance of tumor cells by reducing the related protein expression, achieving a high inhibition efficiency with the synergistic effect of chemotherapeutic drugs. By the selection of a strong electron-withdrawing unit, the emission peak of the luminogen could reach 973 nm. Moreover, this luminogen shows outstanding photothermal conversion ability and improved thermal stability compared to ICG. Notably, after the photothermal treatment of drug-resistant tumor cells by the NIR II luminogen, the antitumor efficiency of chemotherapeutic drugs, including paclitaxel, cis-platinum, and doxorubicin, was significantly enhanced. The mechanism exploration revealed that drug resistance-related proteins were remarkably reduced, making the cells more sensitive toward drugs. Thus, this strategy demonstrated a promising and reliable approach to reverse the drug resistance of tumor cells for efficient tumor inhibition in the clinic.

Resveratrol inhibits ferroptosis in the lung tissues of heat stroke-induced rats via the Nrf2 pathway

BackgroundHeat stroke (HS) can lead to the development of pulmonary ferroptosis. The inhibition of pulmonary ferroptosis during HS improves patient prognosis. The aim of this study was to investigate the effects of resveratrol (RES) on heat stress at an ambient temperature of 42 °C.MethodsHeat stress was induced in Beas-2B cells and lung injury was induced in HS rats at an ambient temperature of 42 °C. The anti-oxidative stress and anti-ferroptotic effects of RES were confirmed through tail vein injection of nuclear factor-2 associated factor (Nrf2) shRNA recombinant adeno-associated virus 6 (AAV6-shNrf2).ResultsRES treatment attenuated the upregulation of reactive oxygen species (ROS) and malondialdehyde (MDA) levels and alleviated glutathione inhibition in HS. In addition, RES treatment reduced the accumulation of Fe2+ in heat-stressed Beas-2B cells and increased the ferroptosis resistance-related proteins FTH1, GPX4, and SLC7A11 as well as the anti-oxidative stress pathway proteins Nrf2, NQO1, and HO-1. The antioxidant and anti-ferroptotic effects of RES in heat-stressed Beas-2B cells were effectively reversed upon treatment with Nrf2-IN-1, an Nrf2 pathway inhibitor. In the HS rat model, the antioxidant and anti-ferroptotic effects of RES were reversed by an ambient temperature of 42 °C and relative humidity of 60 ± 5%.ConclusionsRES effectively protected HS rats from lung injury, inhibited the accumulation of Fe2+, ROS, and MDA in the lung, and upregulated FTH1, GPX4, SLC7A11, Nrf2, NQO1, and HO-1.Graphical

MicroRNA-429 overexpression overcomes imatinib resistance of glioma cells by negatively regulating lysophosphatidic acid receptor 1

ABSTRACT Background Glioma is one of the most aggressive and lethal malignancies in central nervous system. It has been reported that miR-429 is declined in glioma and functions as a tumor suppressor. Nonetheless, the potential role of miR-429 in drug resistance of glioma is still ambiguous. Methods Stable imatinib-resistant lines U251-AR and T98G-AR were established using glioma cell lines U251 and T98G. Cell apoptosis and cycle were analyzed by flow cytometry, and CCK-8 assay was utilized to measure cell viability. Protein and RNA levels were tested with western blot and RT-qPCR. The predicted binding site was confirmed by dual luciferase reporter assay. Results Imatinib-resistant U251-AR and T98G-AR cells presented lower level of miR-429 and higher level of LPAR1. MiR-429 overexpression obviously promoted imatinib sensitivity in glioma cells, indicated by the reduced IC50 value, facilitated cell apoptosis and cell cycle arrest at G0/G1 phase, and downregulated multidrug resistance-related proteins. LPAR1 was verified as a direct target of miR-429 and its expression was negatively regulated by miR-429. Additionally, overexpression of LPAR1 restrained the biological function of miR-429 on imatinib chemoresistance. Conclusion MiR-429 partly sensitized glioma cells to imatinib via downregulation LPAR1, which might provide an approach to overcome imatinib chemoresistance during glioma treatment.

The anthraquinone derivative KA-4s reduces energy metabolism and enhances the sensitivity of ovarian cancer cells to cisplatin.

Ovarian cancer is the leading cause of death from female gynecological cancers. Cisplatin (DDP)is a first-line drug for ovarian cancer treatment. Due to DDP resistance, there is an urgent need for novel therapeutic drugs with improved antitumor activity. AMPK-mediated metabolic regulatory pathways are related to tumor drug resistance. Our study aimed to determine the relationship between reversing DDP resistance with the anthraquinone derivative KA-4s and regulating AMPK energy metabolism in ovarian cancer. The results showed that KA-4s inhibited the proliferation of ovarian cancer cells. The combination of KA-4s with DDP effectively promoted drug-resistant ovarian cancer cell apoptosis and inhibited cell migration and invasion. Moreover, KA-4s decreased the intracellular ATP level and increased the calcium ion level, leading to AMPK phosphorylation. Further studies suggested that the AMPK signaling pathway may be involved in the mechanism through which KA-4s reduce drug resistance. KA-4s inhibited mitochondrial respiration and glycolysis; downregulated the glucose metabolism-related proteins GLUT1 and GLUT4; the lipid metabolism-related proteins SREBP1 and SCD1; and the drug resistance-related proteins P-gp, MRP1, and LRP. The inhibitory effect of KA-4s on GLUT1 was confirmed by the application of the GLUT1 inhibitor BAY-876. KA-4s combined with DDP significantly increased the expression of p-AMPKand reduced the expression of P-gp. In a xenograft model of ovarian cancer, treatment with KA-4s combined with DDP reduced energy metabolism and drug resistance, inducing tumor apoptosis. Consequently, KA-4s might be evaluated as a new agent for enhancing the chemotherapeutic efficacy of treatment for ovarian cancer.

Integrated microbiome and metabolome analysis reveals synergistic efficacy of basil polysaccharide and gefitinib in lung cancer through modulation of gut microbiota and fecal metabolites

Emerging evidence suggests that gut microbiota and its metabolites significantly influence the effectiveness of EGFR-TKIs (e.g., gefitinib, erlotinib) in lung cancer treatment. Plant polysaccharides can interact with gut microbiota, leading to changes in the host-microbe metabolome that may affect drug metabolism and therapeutic outcomes. Our previous research demonstrated the efficacy of basil polysaccharide (BPS) in treating various cancers by regulating hypoxic microenvironment and inhibiting epithelial-mesenchymal transition process. However, the potential impact of BPS on gut microbiota has not been thoroughly explored. In this study, we employed an immunodeficient gefitinib-resistant xenograft mouse model to explore whether BPS enhances the antitumor effects of gefitinib. A multi-omics approach, including 16S rDNA amplicon sequencing and LC-MS, was used to elucidate these synergistic effects. Our findings indicate that BPS can enhance tumor responsiveness to gefitinib by modulating the gut microbiota and its metabolites through multiple metabolic pathways. These changes in gut microbiota and metabolites could potentially affect cancer related signaling pathway and lung resistance-related protein, which are pivotal in determining the efficacy of EGFR-TKIs in cancer treatment.

Phytoconstituent and In silico Screening of Active Compounds from Red Ginger (Zingiber officinale var. rubrum Theilade) Rhizome and Avocado (Persea americana Mill.) Leaves Extracts as Novel Inhibitors of MRSA

Red ginger rhizome (Zingiber officinale var. Rubrum) and avocado leaves (Persea americana Mill.) are empirically known as one of the medicinal plants used in Taro Village, Gianyar Regency, Bali which have great potential in treating infectious diseases caused by antibiotic resistance, such as MRSA. This study aims to analyze the phytoconstituents and anti-MRSA potential contained in red ginger rhizome and avocado leaves extracts by assessing their inhibitory effects on three proteins related to MRSA resistance and virulence (PBAP2a, transglycosylase, and glycosyltransferase). Phytoconstituents of avocado leaf and red ginger extracts were analyzed using GC-MS. Molecular docking was performed in silico to determine the similarity properties of predicted drugs, bioactivity, toxicity, identification of active sites and validation of protein structures, and docking simulations were performed between compounds found in the extract and their target proteins. Phytoconstituent analysis revealed that avocado leaves and red ginger extracts as a whole have 43 types of compounds and 10 bioactive compounds each with beneficial drug-like properties. The compound 6,11-hexadecadien-1-ol from avocado leaves extracts was predicted to have hepatotoxic properties. There were at least 3 compounds, namely beta-bisabolene from avocado leaves extract, zingiberenol and gamma-curcumene from red ginger rhizome extract, showing the lowest binding affinity for the target protein. Red ginger rhizome and avocado leaves extracts showed valuable potential as anti-MRSA agents through the mechanism of inhibition of three resistance-related proteins, as predicted by in silico analysis.

MiR-133 promotes the multidrug resistance of acute myeloid leukemia cells (HL-60/ADR) to daunorubicin.

This study aimed to explore the role and molecular mechanism of miR-133 in multidrug resistance in acute myeloid leukemia (AML) and provide a new theoretical basis for the treatment and prognosis of AML patients. We performed experiments at the cellular level. RT‒qPCR and Western blotting were used to detect gene and protein expression; cell viability was measured with CCK-8 assays; apoptosis was detected via flow cytometry; and a dual-luciferase reporter gene assay was used to verify the binding between miR-133 and CXCL12. In this study, we found that miR-133 was upregulated in HL-60/ADR multidrug-resistant cells. Functionally, the inhibition of miR-133 alleviated the resistance of HL-60/ADR cells to daunorubicin (DNR). After inhibiting miR-133 in HL-60/ADR cells treated with DNR, the expression of the intracellular drug resistance-related proteins MRP562 and P-gp was inhibited, cell proliferation decreased, and apoptosis increased. Mechanistically, the NF-κB signaling pathway regulates the expression of miR-133 in HL-60/ADR cells, and the targeting of CXCL12 by miR-133 enhances the resistance of HL-60/ADR cells to DNR. In conclusion, the NF-κB signaling pathway regulates the expression of miR-133, and inhibiting miR-133 expression can target CXCL12 to increase the sensitivity of HL-60/ADR cells to DNR.

In silico analysis of drug-resistant genes of Staphylococcus aureus

Drug-resistant strains of pathogenic bacteria are recently considered a devastating health problem. Staphylococcus aureus is a bacterium that commonly lives on the skin and in the nasal passages of approximately one-third of the population without causing any harm. One of the major concerns with Staphylococcus aureus is its ability to develop antibiotic resistance. Drug-resistant genes play an important role in determining the characteristics of bacteria mechanisms of drug resistance. The identification of promoters in a gene is an important part of the recognition of a gene's complete structure. An in silico study was done to analyze the promoter regions and transcription factors with the aid of the transcription start site, regulatory elements, and motifs of genes. Most of the predicted transcription start sites (75 %) were found above 500 bp value either upstream or downstream from the start codon of the gene being expressed. Motif I was identified as the most common motif for the predicted genes, which serves as binding sites to regulate the expression of the genes. A variety of regulatory elements including enhancers, insulators, transcription factors, and cellular proteins are involved in the regulation of gene expression. In general, in silico analysis of drug-resistant genes of Staphylococcus aureus could provide valuable insights about the transcription factor binding, and gene regulatory elements in the promoter regions that can lead to promising research targets in drug designing and development. Therefore, further studies should be made to study resistance-related proteins, the protein-protein interaction networks, the pathways involved in mechanisms underlying resistance, and facilitating the design of target-specific drugs.

Bioinformatics study of bortezomib resistance-related proteins and signaling pathways in mantle cell lymphoma.

The bortezomib (BTZ) resistance mechanisms in mantle cell lymphoma (MCL) are complex, involving various genes and signaling pathways. This study used bioinformatical tools to identify and analyze differentially expressed genes (DEGs) associated with BTZ resistance. Gene chip datasets containing MCL BTZ-resistant and normal control cohorts (GSE20915 and GSE51371) were selected from the Gene Expression Omnibus (GEO) database. GEO2R was used to identify the upregulated DEGs in the microarray datasets, using a significance threshold of P<0.05. Subsequently, these DEGs were subjected to a Gene Ontology (GO) functional analysis, a Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and a protein-protein interaction (PPI) network assessment. Additionally, 40 MCL patients who underwent second-line BTZ treatment were included in this study. The patients were categorized into resistant and sensitive groups based on treatment response. The enzyme-linked immunosorbent assay (ELISA) technique was employed to evaluate the expression levels of specific DEGs in the serum of the patients in both groups. In the GSE20915 dataset, 144 upregulated genes were identified as DEGs. Similarly, in the GSE51371 dataset, 219 upregulated genes were identified as DEGs. By employing a Venn diagram to compare the upregulated DEGs from both datasets, we identified 11 DEGs linked to BTZ resistance in MCL. The enrichment analysis of the KEGG signaling pathways revealed that the DEGs were predominantly enriched in key biological processes (BP), including the cell cycle, cellular senescence, the p53 signaling pathway, the interleukin 17 (IL-17) signaling pathway, and the nuclear factor kappa-B (NF-κB) signaling pathway. A distinct cluster was revealed by creating a PPI network and performing a module analysis of a set of typical DEGs. This cluster comprised four candidate genes; that is, cyclin-dependent kinase inhibitor 1A (CDKN1A), CDKN1C, midkine (MDK), and TNF alpha induced protein 3 (TNFAIP3). Among these genes, MDK was found to be the key gene. The serum concentration of MDK in the resistant group [1,539 (1,212, 2,023) ng/L] was significantly higher than that in the sensitive group [1,175 (786, 1,502) ng/L] (P<0.05). Identifying the key gene MDK and its associated signaling pathways extends our understanding of the molecular processes that underlie resistance to BTZ in MCL. This discovery establishes a theoretical framework for future investigations of targeted therapy in clinical settings.

Solution NMR backbone resonance assignment of the full-length resistance-related calcium-binding protein Sorcin.

Sorcin is a penta-EF hand calcium-binding protein that confers multidrug resistance in cancer cells. It regulates cellular Ca2+ homeostasis by interacting with calcium channels such as Ryanodine receptor 2 and Sarcoplasmic/endoplasmic reticulum Ca2+-ATPase in a calcium-dependent manner. The crystal structure of the Sorcin has been determined in both calcium-free and calcium-bound states to understand calcium-binding induced conformational change. However, due to its flexibility, most of the N-terminal domain is invisible in these crystal structures. Here we report the 1H, 13C, and 15N backbone resonance assignments of full-length Sorcin in the calcium-free state using solution NMR. The protein secondary structure was predicted based on the assigned backbone chemical shifts using TALOS+ and CSI 3.0. Our backbone resonance assignment of the full-length Sorcin provides a foundation for future NMR spectroscopic studies to uncover the mechanism of Ca2+ sensing by Sorcin.

Major Vault Protein/Lung Resistance-Related Protein: A Novel Biomarker for Inflammation and Acute Infections.

Vault particles are large cytoplasmic ribonucleoprotein particles that participate in inflammation. The aim of this study was to assess the diagnostic and prognostic value of major vault protein (MVP) in patients with inflammation, in order to determine whether MVP could be used as a biomarker for infection or inflammation. We also aimed to compare the diagnostic impact of MVP compared to other conventional measurements, such as CRP or white blood cell (WBC) counts. CRP and MVP levels were measured in 111 sera samples from 85 patients with inflammation admitted to a tertiary-care hospital and 26 healthy individuals during an 18-month period (2019-2020), using nephelometry and a custom MVP sandwich ELISA assay, respectively. In addition, WBC counts were measured using a commercial assay. MVP levels were found to be elevated in patients with inflammation compared to healthy individuals (p < 0.0001). Moreover, MVP levels were higher in patients with inflammation due to an infectious etiology compared to those with non-infectious etiology (p = 0.0006). MVP levels significantly decreased during the first four days of infection in response to antibiotic treatment, while CRP levels showed a less-sensitive decline. An ROC curve analysis demonstrated that MVP and CRP have similarly high diagnostic accuracy, with AUCs of 0.955 and 0.995, respectively, followed by WBCs with an AUC of 0.805. The ROC curves demonstrated that MVP has the potential to serve as a diagnostic biomarker for inflammation and infection. Additionally, MVP levels may reflect the efficacy of antibiotic treatment.

Transcription combined metabolic analysis reveals the mechanism of potassium phosphate enhances resistance to walnut anthracnose (Colletotrichum gloeosporioides)

Given the increasingly serious diseases [anthracnose mainly caused by Colletotrichum gloeosporioides (C. gloeosporioides)] of walnut plants in recent years and the environmental pollution caused by chemical pesticides, phosphites had been shown to be new environmental friendly chemical agents for plants. In this study, seven-year-old ‘Xiangling’ and ‘Xifu 4’ walnut trees were treated with different concentrations of potassium phosphite foliar fertilizer. The treatments were T1 (1500-fold dilution fluid of potassium phosphite), T2 (1000-fold dilution fluid of potassium phosphite) and CK (water). The results showed that the disease incidence rates of fruit treated with potassium phosphite were lower than CK. Moreover, the diseased fruit rates of ‘Xiangling’ (4) and ‘Xifu 4’ (14) in T2, lower than they (28 and 38) in CK. Metabolome and transcriptome further analysis revealed that potassium phosphite significantly increased the expression level of genes in the photosynthesis pathway and accumulated terpeniods, phenolic, salicylic acid and other secondary metabolic pathways. In addition, as salicylic acid content significantly increased, the expression level of the gene encoding the disease resistance-related protein (PR1) showed a corresponding trend. In vitro antibacterial tests of six related metabolites on C. gloeosporioides showed that hederagenin, 23-hydroxybetulinic acid, ursolic acid, eriodictyol, and salicylic acid had effect on C. gloeosporioides spores, among which salicylic acid and ursolic acid significantly inhibited the growth of C. gloeosporioides. Further experiments revealed that the minimum inhibitory concentrations of salicylic acid and ursolic acid were 2 and 5 g L−1, respectively. In addition, potassium phosphite could directly inhibit the growth of C. gloeosporioides spores in vitro tests. In conclusion, potassium phosphite enhanced walnut fruit disease resistance through up-regulated the genes related to photosynthetic performance and abundant in secondary metabolites, such as salicylic acid, terpenoids and phenolics, which were antibacterial effects on C. gloeosporioides.

Clinical Analysis of Multidrug Resistance-Related Protein Expression in Gastric Cancer Cells

Objective: This study aims to clinically analyze the expression of multidrug resistance-related proteins in gastric cancer cells. Methods: In this study, archival paraffin blocks from 50 surgical specimens of gastric cancer collected in our hospital between 2021 and 2022 were included. Each specimen included tumor lesion tissue and normal gastric mucosa tissue located more than 5 cm away from the cancer. Immunohistochemistry was performed to detect P-glycoprotein (P-gp), glutathione S-transferase pi (GST-π), and B-cell lymphoma-extra-large (Bcl-xL) expression, and the relevant data were collected and analyzed. Results: The positive expression rates and high expression levels of P-gp, GST-π, and Bcl-xL in gastric cancer tissues were significantly higher than in normal gastric mucosa tissues (p &lt; 0.05). The expression of multidrug resistance proteins (P-gp, GST-π, Bcl-xL) in gastric cancer was not associated with patient clinical characteristics (tumor clinical stage, depth of invasion, and lymph node metastasis) (p &gt; 0.05); Bcl-xL expression level was positively correlated with tumor differentiation degree (p &lt; 0.05). Conclusion: The results of this study reveal the expression patterns of multidrug resistance-related proteins in gastric cancer tissues and shed light on the relationship between the expression of these proteins and multidrug resistance in gastric cancer.

Sorcin in Cancer Development and Chemotherapeutic Drug Resistance.

SOluble Resistance-related Calcium-binding proteIN (sorcin) earned its name due to its co-amplification with ABCB1 in multidrug-resistant cells. Initially thought to be an accidental consequence of this co-amplification, recent research indicates that sorcin plays a more active role as an oncoprotein, significantly impacting multidrug resistance (MDR). Sorcin is a highly expressed calcium-binding protein, often overproduced in human tumors and multidrug-resistant cancers, and is a promising novel MDR marker. In tumors, sorcin levels inversely correlate with both patient response to chemotherapy and overall prognosis. Multidrug-resistant cell lines consistently exhibit higher sorcin expression compared to their parental counterparts. Furthermore, sorcin overexpression via gene transfection enhances drug resistance to various chemotherapeutic drugs across numerous cancer lines. Conversely, silencing sorcin expression reverses drug resistance in many cell lines. Sorcin participates in several mechanisms of MDR, including drug efflux, drug sequestering, cell death inhibition, gene amplification, epithelial-to-mesenchymal transition, angiogenesis, and metastasis. The present review focuses on the structure and function of sorcin, on sorcin's role in cancer and drug resistance, and on the approaches aimed at targeting sorcin.

Refinement of rice blast disease resistance QTLs and gene networks through meta-QTL analysis

Rice blast disease is the most devastating disease constraining crop productivity. Vertical resistance to blast disease is widely studied despite its instability. Clusters of genes or QTLs conferring blast resistance that offer durable horizontal resistance are important in resistance breeding. In this study, we aimed to refine the reported QTLs and identify stable meta-QTLs (MQTLs) associated with rice blast resistance. A total of 435 QTLs were used to project 71 MQTLs across all the rice chromosomes. As many as 199 putative rice blast resistance genes were identified within 53 MQTL regions. The genes included 48 characterized resistance gene analogs and related proteins, such as NBS–LRR type, LRR receptor-like kinase, NB-ARC domain, pathogenesis-related TF/ERF domain, elicitor-induced defense and proteins involved in defense signaling. MQTL regions with clusters of RGA were also identified. Fifteen highly significant MQTLs included 29 candidate genes and genes characterized for blast resistance, such as Piz, Nbs-Pi9, pi55-1, pi55-2, Pi3/Pi5-1, Pi3/Pi5-2, Pikh, Pi54, Pik/Pikm/Pikp, Pb1 and Pb2. Furthermore, the candidate genes (42) were associated with differential expression (in silico) in compatible and incompatible reactions upon disease infection. Moreover, nearly half of the genes within the MQTL regions were orthologous to those in O. sativa indica, Z. mays and A. thaliana, which confirmed their significance. The peak markers within three significant MQTLs differentiated blast-resistant and susceptible lines and serve as potential surrogates for the selection of blast-resistant lines. These MQTLs are potential candidates for durable and broad-spectrum rice blast resistance and could be utilized in blast resistance breeding.

Combination therapy using Cel-CSO/Taxol NPs for reversing drug resistance in breast cancer through inhibiting PI3K/AKT/NF-κB/HIF-1α pathway.

The resistance of malignant tumors to multiple drugs is a significant obstacle in cancer treatment and prognosis. Accordingly, we synthesized a celastrol (Cel) prodrug (Cel-CSO) by conjugating chitosan oligosaccharides (CSO) to Cel for reversing Taxol resistance in chemotherapy, followed by self-assembly with Taxol into a novel nanoplatform of Cel-CSO/Taxol nanoparticles (termed NPs). NPs showed a suitable size (about 153nm), excellent stability and prolonged release of Cel and Taxol in a manner that depended on both pH and time. NPs effectively inhibited the overexpression of multidrug resistance-related protein P-gp, hypoxia inducible factor-1α (HIF-1α), and triggered the MCF-7/Taxol cell apoptosis through inhibiting the PI3K/AKT/NF-κB/HIF-1α pathway. In tumor-bearing mice, NPs exhibited significant curative effects in inducing apoptosis of MCF-7/Taxol tumors which showed a low expression level of P-gp, microtubule-related proteins TUBB3 and Tau. The results indicated that NPs may be a promising strategy to overcome drug resistance caused by P-gp, which improve the antitumor effects in drug-resistant breast cancer.

USP14 increases the sensitivity of retinoblastoma to cisplatin by mediating the ferroptosis

The aim of this study is to explore the function of USP14 on the sensitivity of retinoblastoma (RB) to cisplatin (DDP) and the underlying mechanism. USP14 was knockdown in Y79 cells by transfecting three siRNAs (si-USP14-1, si-USP14-2, and si-USP14-3), with si-USP14 NC as the negative control. si-USP14-3 was selected by results of Western blotting. The CCK-8 assay was used to detect the IC50 of Y79 cells and the growth curve. The cell cycle, cell apoptosis, and ROS level were measured by flow cytometry. The expression level of P-GP, ERCC1, survivin, GPX4, FTH1, ACSL4, NOX1, COX2, and FASN was determined by the Western blotting assay. CO-IP assay was utilized to evaluate the interaction between USP14 and FASN. The IC50 of DDP in Y79 cells and Y79/DDP cells was 7.83 µM and 24.67 µM, respectively. Compared to control and si-USP14 NC groups, increased apoptotic rate and ROS level, and arrested cell cycle in S phase were observed in USP14-knockdown Y79 cells. Compared to control and si-USP14 NC groups, increased apoptotic rate and arrested cell cycle in G0/G1 phase were observed in USP14-knockdown Y79/DDP cells. Compared to control, increased ROS level was observed in USP14-knockdown Y79/DDP cells. Compared to the si-USP14 NC groups, extremely downregulated P-GP, ERCC1, survivin, GPX4, FTH1, NOX1, COX2, and FASN were observed in USP14-knockdown Y79 cells or Y79/DDP cells, accompanied by the elevated expression of ACSL4. The interaction between USP14 and FASN was identified according to the result of CO-IP assay. By silencing USP14 in Y79 and Y79/DDP cells, levels of resistance-related proteins (P-GP, ERCC1, and survivin), ferroptosis-related proteins (FTH1 and GPX4), and lipid metabolism-related proteins (NOX1, COX2, and FASN) were dramatically reduced, accompanied by enhanced ROS level, increased apoptosis, and restrained DNA content, indicating that USP14 might suppress the DDP resistance in RB by mediating ferroptosis, which is an important target for treating RB.