Cytoplasmic RAP1 mediates cisplatin resistance of non-small cell lung cancer

Transcriptome analysis reveals PRKCA as a potential therapeutic target for overcoming cisplatin resistance in lung cancer through ferroptosis

Cisplatin-based chemotherapy is the current standard care for lung cancer patients; however, drug resistance frequently develops during treatment, thereby limiting therapeutic efficacy.The molecular mechanisms underlying cisplatin resistance remain elusive. In this study, we conducted an analysis of microarray data from the Gene Expression Omnibus (GEO) database under the accession numbers GSE21656, which encompassed expression profiling of cisplatin-resistant H460 (DDP-H460)and the parental cells (H460). Subsequently, we calculated the differentially expressed genes (DEGs) between DDP-H460 and H460. Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of DEGs demonstrated significant impact on the Rap1, PI3K/AKT and MAPK signaling pathways. Moreover, protein and protein interaction (PPI) network analysis identified PRKCA, DET1, and UBE2N as hub genes that potentially contribute predominantly to cisplatin resistance. Ultimately, PRKCA was selected for validation due to its significant prognostic effect, which predicts unfavorable overall survival and disease-free survival in patients with lung cancer. Network analysis conducted on The Cancer Genome Atlas (TCGA) database revealed a strong gene-level correlation between PRKCA and TP53, CDKN2A, BYR2, TTN, KRAS, and PIK3CA; whereas at the protein level, it exhibited a high correlation with EGFR, Lck, Bcl2, and Syk. The in vitro experiments revealed that PRKCA was upregulated in the cisplatin-resistant A549 cells (DDP-A549), while knockdown of PRKCA increased DDP-A549 apoptosis upon cisplatin treatment. Moreover, we observed that PRKCA knockdown attenuated DDP-A549 proliferation, migration and invasion ability. Western blot analysis demonstrated that PRKCA knockdown downregulated phosphorylation of PI3K expression while upregulated the genes involved in ferroptosis signaling. In summary, our results elucidate the role of PRKCA in acquiring resistance to cisplatin and underscore its potential as a therapeutic target for cisplatin-resistant lung cancer.

LncRNA AC100826.1 regulated PLCB1 to promote progression in non-small cell lung cancer

BACKGROUND

Lung cancer is the most common malignant tumor. In the present study, we identified a long non-coding RNA (lncRNA) AC100826.1 (simplify to Lnc1), which was highly expressed in non-small cell lung cancer (NSCLC) tissues compared with the paracancerous tissues. We also observed the critical role of Lnc1 in regulating the metastasis ability of NSCLC cells.

METHODS

RNA sequencing was performed to detect differential expression levels of lncRNAs in NSCLC tissues and its paracancerous tissues. Effects of Lnc1 on cell proliferation, invasion, and migration were determined by CCK-8, transwell and scratch assays. The xenograft experiment confirmed the effect of Lnc1 on NSCLC cells proliferation and migration abilities in vivo. RT-qPCR and western blots were performed to determine the expression levels of mRNAs and proteins.

RESULTS

The expression level of Lnc1 was related to multiple pathological results, knockdown of Lnc1 can inhibit the proliferation and metastasis abilities of NSCLC cells. silencing phospholipase C, β1(PLCB1) can reverse the promoting effects of overexpression Lnc1 on NSCLC cells proliferation and migration abilities. In addition, the Rap1 signaling pathway was implicated in the regulation of Lnc1 in NSCLC metastasis.

CONCLUSION

Our results suggest that Lnc1 regulated the metastatic ability of NSCLC cells through targeting the PLCB1/Rap1 signal pathway.

Glucotoxicity is mediated by cytoplasmic distribution of RAP1 in pancreatic β-cells

Diabetes mellitus (DM) is a group of chronic metabolic disorders characterized by persistent hyperglycemia. In our study, we analyzed the level and location of RAP1 changes in the development of β-cell dysfunction induced by glucotoxicity. We employed three pancreatic β-cell lines, namely INS-1, 1.2B4, and NIT-1, as well as a streptozotocin-induced diabetes rat model. We demonstrate that after high glucose treatment, RAP1 is increased, probably through induction by AKT, allowing RAP1 to shuttle from the nucleus to the cytoplasm and activate NF-κB signaling. Furthermore, non-enzymatic post-translational modifications of RAP1, such as advanced glycation end products and carbonylation may affect the function of RAP1, such as activation of the NF-κB signaling. Taken together, we showed that RAP1 is a new player in the mechanism of glucotoxicity in pancreatic β-cells.

The Efficacy of Ganoderma lucidum Extracts on Treating Endometrial Cancer: A Network Pharmacology Approach

Ganoderma lucidum (GL) is a prominent medicinal mushroom in traditional Chinese medicine, known for its potent antitumor properties. This study aimed to illustrate the efficacy of GL extracts (GLE) on treating endometrial cancer (EC) and explore the underlying mechanisms via network pharmacology and experimental validation. Network pharmacological analysis was conducted to explore the therapeutic efficacy and mechanisms of GL on EC. In vitro experimental validation was performed on human endometrial cancer cell lines HEC-1-A and KLE. Network pharmacology revealed that key targets of GL against EC were primarily associated with the Rap1 signaling pathway. In in vitro experiments, GLE or GGTI-298 (a GTPase inhibitor) treatment inhibited cell proliferation and migration, promoted cell apoptosis, increased caspase-3 level, and arrested cell cycle in G1 phase in HEC-1-A and KLE cells. GLE increased the protein expression of Rap1-GTP, p-AKT, and p-ERK2 in HEC-1-A and KLE cells. Moreover, GGTI-298 enhanced the effects of GLE on suppressing the malignant progression of EC cells and on activating Rap1 signaling pathway. GLE inhibited the malignant progression of EC cells probably via activating the Rap1 signaling pathway.

Plk3 Enhances Cisplatin Sensitivity of Nonsmall-Cell Lung Cancer Cells through Inhibition of the PI3K/AKT Pathway via Stabilizing PTEN

Polo-like kinase 3 (Plk3) is involved in tumor development with a tumor suppressive function. However, the effect of Plk3 on the chemoresistance remains unclear. It has been documented that activation of the PI3K/AKT signaling pathway by PTEN loss significantly enhances chemoresistance in nonsmall-cell lung cancer (NSCLC). This study aims to evaluate the PTEN regulation by Plk3 and identify targets and underlying mechanisms that could be used to relieve chemoresistance. Our results showed that silencing Plk3 reduced PTEN expression and activated PI3K/AKT signaling by dephosphorylating and destabilizing PTEN in NSCLC cells. Reducing Plk3 expression promoted drug resistance to cisplatin (DDP), while overexpressing Plk3 promoted DDP sensitivity. However, these effects were attenuated when MK2206, a PI3K/AKT inhibitor, was applied. In conclusion, upregulation of Plk3 sensitized NSCLC cells toward DDP, which provides a potential target to restore DDP chemoresponse. We provided novel evidence that the PTEN/PI3K/AKT signaling pathway could be regulated by Plk3 through phosphorylation of PTEN and highlighted the critical role of Plk3 in the DDP resistance of NSCLC.

Downregulating miR-184 relieves calcium oxalate crystal-mediated renal cell damage via activating the Rap1 signaling pathway

BACKGROUND

Renal calculi are a very prevalent disease with a high incidence. Calcium oxalate (CaOx) is a primary constituent of kidney stones. Our paper probes the regulatory function and mechanism of miR-184 in CaOx-mediated renal cell damage.

METHODS

CaOx was used to treat HK2 cells and human podocytes (HPCs) to simulate kidney cell damage. The qRT-PCR technique checked the profiles of miR-184 and IGF1R. The examination of cell proliferation was conducted employing CCK8. TUNEL staining was used to monitor cell apoptosis. Western blot analysis was used to determine the protein profiles of apoptosis-concerned related proteins (including Mcl1, Bcl-XL, and Caspase-3), the NF-κB, Nrf2/HO-1, and Rap1 signaling pathways. ELISA confirmed the levels of the inflammatory factors IL-6, TNF-α, MCP1, and ICAM1. The targeting relationship between miR-184 and IGF1R was validated by dual luciferase assay and RNA immunoprecipitation assay.

RESULTS

Glyoxylate-induced rat kidney stones model and HK2 and HPC cells treated with CaOx demonstrated an increase in the miR-184 profile. Inhibiting miR-184 relieved CaOx-mediated renal cell inflammation, apoptosis and oxidative stress and activated the Rap1 pathway. IGF1R was targeted by miR-184. IGF1R activation by IGF1 attenuated the effects of miR-184 on renal cell damage, and Hippo pathway suppression reversed the inhibitory effect of miR-184 knockdown on renal cell impairment.

CONCLUSIONS

miR-184 downregulation activates the Rap1 signaling pathway to ameliorate renal cell damage mediated by CaOx.

Deciphering Treg cell roles in esophageal squamous cell carcinoma: a comprehensive prognostic and immunotherapeutic analysis

Background: Esophageal squamous cell carcinoma (ESCC) is a prevalent and aggressive form of cancer that poses significant challenges in terms of prognosis and treatment. Regulatory T cells (Treg cells) have gained attention due to their influential role in immune modulation within the tumor microenvironment (TME). Understanding the intricate interactions between Treg cells and the tumor microenvironment is essential for unraveling the mechanisms underlying ESCC progression and for developing effective prognostic models and immunotherapeutic strategies. Methods: A combination of single-cell RNA sequencing (scRNA-seq) and bulk RNA-seq analysis was utilized to explore the role of Treg cells within the TME of ESCC. The accuracy and applicability of the prognostic model were assessed through multi-dimensional evaluations, encompassing an examination of the model's performance across various dimensions, such as the mutation landscape, clinical relevance, enrichment analysis, and potential implications for immunotherapy strategies. Results: The pivotal role of the macrophage migration inhibitory factor (MIF) signaling pathway within the ESCC TME was investigated, with a focus on its impact on Treg cells and other subpopulations. Through comprehensive integration of bulk sequencing data, a Treg-associated signature (TAS) was constructed, revealing that ESCC patients with elevated TAS (referred to as high-TAS individuals) experienced significantly improved prognoses. Heightened immune infiltration and increased expression of immune checkpoint markers were observed in high-TAS specimens. The model's validity was established through the IMvigor210 dataset, demonstrating its robustness in predicting prognosis and responsiveness to immunotherapy. Heightened therapeutic benefits were observed in immune-based interventions for high-TAS ESCC patients. Noteworthy differences in pathway enrichment patterns emerged between high and low-TAS cohorts, highlighting potential avenues for therapeutic exploration. Furthermore, the clinical relevance of key model genes was substantiated by analyzing clinical samples from ten paired tumor and adjacent tissues, revealing differential expression levels. Conclusion: The study established a TAS that enables accurate prediction of patient prognosis and responsiveness to immunotherapy. This achievement holds significant implications for the clinical management of ESCC, offering valuable insights for informed therapeutic interventions.

Identification of the therapeutic mechanism of the saffron crocus on glioma through network pharmacology and bioinformatics analysis

Saffron crocus is a herbal medicine of traditional Tibetan medicine (TTM). Saffron extract has been indicated to inhibit tumor cell growth and promote tumor cell apoptosis in a variety of cancers, including glioma, but the specific mechanism is not clear. To study the possible mechanism of saffron action on glioma, network pharmacology and bioinformatics analysis methods were used in this study. We used the online database to obtain the active ingredients of saffron and their targets. Glioma-related targets were also acquired from online database. We intersected drug targets with glioma-related targets and conducted PPI network analysis to obtain network core genes. Then, we obtained RNA-seq data from The Cancer Genome Atlas (TCGA) database for glioma patients. Through different expression analysis and lasso regression, further screening of core genes in the network was conducted, and a prognostic model was established. The sample was divided into two groups with high and low risk using this model. The RNA-seq data from the Chinese Glioma Genome Atlas (CGGA) database were used to further validate our prediction model. Then, we explored the difference in pathways enrichment between high-risk patients and low-risk patients and calculated the difference in immune microenvironment between the two groups. Finally, we used scRNA-seq data in the CGGA database to analyze the cell types in which the model gene is mainly enriched and predicted the cell types which saffron effected on.

Comprehensive analyses of genome-wide methylation and RNA epigenetics identify prognostic biomarkers, regulating the tumor immune microenvironment in lung adenocarcinoma

The aim of our study was to identify a signature of immune-regulated molecules and reveal its prognostic role in lung adenocarcinoma (LUAD). We downloaded RNA-Sequencing data and DNA methylation data from the Gene Expression Omnibus (GEO) database. GEO2R was used to analyze differentially expressed mRNAs (DEmRNAs). we used "factoextra" R package to do the principal component analysis (PCA) of DEmRNAs. "Limma" R package was used to identify DEmRNAs, differentially expressed miRNAs (DEmiRNAs), differentially expressed lncRNAs (DElncRNAs) from The Cancer Genome Atlas (TCGA) database. Three R packages "org.Hs.eg.db", "clusterProfiler", "ggplot2″ were used to show enrichment results. Considering about methylation and mutation data, TEK and SOX17 mediated cancer signaling pathways. Through tumor-immune system interactions database (TISIDB) and Tumor Immune Estimation Resource (TIMER), higher methylated and lower expressed TEK may act as a prognostic marker, regulating the tumor immunity in LUAD. Through four databases (MEXPRESS, DNMIVD, MethSurv, Firehose), we further verified the methylation (P = 2.33e-23) and mutation about TEK. A signature of immune-associated TEK to predict survival of LUAD patients was validated. Prognostic, methylation, immune microenvironment analysis showed new light on potential novel therapeutic targets in LUAD.

Dihydrotanshinone Triggers Porimin-Dependent Oncosis by ROS-Mediated Mitochondrial Dysfunction in Non-Small-Cell Lung Cancer

Lung cancer is one of the leading causes of cancer death. Non-small-cell lung cancer (NSCLC) accounts for the majority of lung cancer diagnoses. Dihydrotanshinone (DHT) is a compound extract from Salvia miltiorrhiza, which has favorable anti-inflammatory and anti-cancer activities. However, the role of DHT in NSCLC has not been fully studied. The anti-cancer drugs used for treating lung cancer often lead to apoptosis; however, the drug resistance of apoptosis restricts the effect of these drugs. Oncosis is a passive form of cell death that is different from apoptosis. It is characterized by cell swelling, and Porimin is a specific marker for oncosis. In this study, the role of DHT in mediating oncosis in A549 cells was investigated. In vitro, the MTS assay was used to detect cell activity after DHT treatment. Microscopy and electron microscopy were used to observe cell morphology changes. Western blotting was used to detect protein expression. Flow cytometry was used to detect intracellular reactive oxygen species (ROS) level, calcium ion (Ca2+) level, and cell mortality. The intracellular Lactic dehydrogenase (LDH) level was detected by an LDH detection kit after DHT treatment. The ATP level was detected using an ATP detection kit. In vivo, Lewis lung cancer (LLC) xenograft mice were used to evaluate the anti-tumor effect of DHT. Hematoxylin and eosin (HE) staining was used to detect the pathology of lung cancer tumors. The detection of Porimin in the tumor tissues of the mice after DHT administration was assessed by immunohistochemistry (IHC). The results of this study showed that DHT treatment changed the cell morphology; destroyed the mitochondrial structure; increased the expression of Porimin; increased the levels of LDH, ROS, and Ca2+; decreased the mitochondrial membrane potential and ATP level; and played an anti-tumor role in vitro by mediating oncosis in A549 cells. The in vivo studies showed that DHT could effectively inhibit tumor growth. The results of protein detection and IHC detection in the tumor tissues showed that the expression of Porimin was increased and that oncosis occurred in the tumor tissues of mice. DHT triggered Porimin-dependent oncosis by ROS-mediated mitochondrial dysfunction in NSCLC. The in vivo studies showed that DHT could inhibit tumor growth in LLC xenograft mice by triggering oncosis. This study indicates the potential for DHT to treat NSCLC.

Integrative analysis illustrates the role of PCDH7 in lung cancer development, cisplatin resistance, and immunotherapy resistance: an underlying target

Background: Cisplatin resistance is a common clinical problem in lung cancer. However, the underlying mechanisms have not yet been fully elucidated, highlighting the importance of searching for biological targets. Methods: Bioinformatics analysis is completed through downloaded public data (GSE21656, GSE108214, and TCGA) and specific R packages. The evaluation of cell proliferation ability is completed through CCK8 assay, colony formation, and EdU assay. The evaluation of cell invasion and migration ability is completed through transwell and wound-healing assays. In addition, we evaluated cell cisplatin sensitivity by calculating IC50. Results: Here, we found that PCDH7 may be involved in cisplatin resistance in lung cancer through public database analysis (GSE21656 and GSE108214). Then, a series of in vitro experiments was performed, which verified the cancer-promoting role of PCDH7 in NSCLC. Moreover, the results of IC50 detection showed that PCDH7 might be associated with cisplatin resistance of NSCLC. Next, we investigated the single-cell pattern, biological function, and immune analysis of PCDH7. Importantly, we noticed PCDH7 may regulate epithelial-mesenchymal transition activity, and the local infiltration of CD8+ T and activated NK cells. Furthermore, we noticed that patients with high PCDH7 expression might be more sensitive to bortezomib, docetaxel, and gemcitabine, and resistant to immunotherapy. Finally, a prognosis model based on three PCDH7-derived genes (GPX8, BCAR3, and TNS4) was constructed through a machine learning algorithm, which has good prediction ability on NSCLC patients' survival. Conclusion: Our research has improved the regulatory framework for cisplatin resistance in NSCLC and can provide direction for subsequent related research, especially regarding PCDH7.

Possible molecular mechanisms underlying the development of atherosclerosis in cancer survivors

Cancer survivors undergone treatment face an increased risk of developing atherosclerotic cardiovascular disease (CVD), yet the underlying mechanisms remain elusive. Recent studies have revealed that chemotherapy can drive senescent cancer cells to acquire a proliferative phenotype known as senescence-associated stemness (SAS). These SAS cells exhibit enhanced growth and resistance to cancer treatment, thereby contributing to disease progression. Endothelial cell (EC) senescence has been implicated in atherosclerosis and cancer, including among cancer survivors. Treatment modalities for cancer can induce EC senescence, leading to the development of SAS phenotype and subsequent atherosclerosis in cancer survivors. Consequently, targeting senescent ECs displaying the SAS phenotype hold promise as a therapeutic approach for managing atherosclerotic CVD in this population. This review aims to provide a mechanistic understanding of SAS induction in ECs and its contribution to atherosclerosis among cancer survivors. We delve into the mechanisms underlying EC senescence in response to disturbed flow and ionizing radiation, which play pivotal role in atherosclerosis and cancer. Key pathways, including p90RSK/TERF2IP, TGFβR1/SMAD, and BH4 signaling are explored as potential targets for cancer treatment. By comprehending the similarities and distinctions between different types of senescence and the associated pathways, we can pave the way for targeted interventions aim at enhancing the cardiovascular health of this vulnerable population. The insights gained from this review may facilitate the development of novel therapeutic strategies for managing atherosclerotic CVD in cancer survivors.

Enhanced binding of β-catenin and β-TrCP mediates LMPt's anti-CSCs activity in colorectal cancer

Cancer stem cells (CSCs), a subpopulation of tumor cells with the features of self-renewal, tumor initiation, and insensitivity to common physical and chemical agents, are the key to cancer relapses, metastasis, and resistance. Accessible CSCs inhibitory strategies are primarily based on small molecule drugs, yet toxicity limits their application. Here, we report a liposome loaded with low toxicity and high effectiveness of miriplatin, lipo-miriplatin (LMPt) with high miriplatin loading, and robust stability, exhibiting a superior inhibitory effect on CSCs and non-CSCs. LMPt predominantly inhibits the survival of oxaliplatin-resistant (OXA-resistant) cells composed of CSCs. Furthermore, LMPt directly blocks stemness features of self-renewal, tumor initiation, unlimited proliferation, metastasis, and insensitivity. In mechanistic exploration, RNA sequencing (RNA-seq) revealed that LMPt downregulates the levels of pro-stemness proteins and that the β-catenin-mediated stemness pathway is enriched. Further research shows that either in adherent cells or 3D-spheres, the β-catenin-OCT4/NANOG axis, the vital pathway to maintain stemness, is depressed by LMPt. The consecutive activation of the β-catenin pathway induced by mutant β-catenin (S33Y) and OCT4/NANOG overexpression restores LMPt's anti-CSCs effect, elucidating the key role of the β-catenin-OCT4/NANOG axis. Further studies revealed that the strengthened binding of β-catenin and β-TrCP initiates ubiquitination and degradation of β-catenin induced by LMPt. In addition,the Apc^Min/+transgenicmouse model, in which colon tumors are spontaneously formed, demonstrates LMPt's potent anti-non-CSCs activity in vivo.

Aberrant expression and localization of the RAP1 shelterin protein contribute to age-related phenotypes

Short telomeres induce a DNA damage response (DDR) that evokes apoptosis and senescence in human cells. An extant question is the contribution of telomere dysfunction-induced DDR to the phenotypes observed in aging and telomere biology disorders. One candidate is RAP1, a telomere-associated protein that also controls transcription at extratelomeric regions. To distinguish these roles, we generated a knockin mouse carrying a mutated Rap1, which was incapable of binding telomeres and did not result in eroded telomeres or a DDR. Primary Rap1 knockin embryonic fibroblasts showed decreased RAP1 expression and re-localization away from telomeres, with an increased cytosolic distribution akin to that observed in human fibroblasts undergoing telomere erosion. Rap1 knockin mice were viable, but exhibited transcriptomic alterations, proinflammatory cytokine/chemokine signaling, reduced lifespan, and decreased healthspan with increased body weight/fasting blood glucose levels, spontaneous tumor incidence, and behavioral deficits. Taken together, our data present mechanisms distinct from telomere-induced DDR that underlie age-related phenotypes.

Evaluation of circulating small extracellular vesicle-derived miRNAs as diagnostic biomarkers for differentiating between different pathological types of early lung cancer

Lung cancer is the leading cause of cancer-related death worldwide. MicroRNAs (miRNAs) in circulating small extracellular vesicles (sEVs) have been suggested to be potential biomarkers for cancer diagnosis. The present study was designed to explore whether plasma-derived sEV miRNAs could be utilized as diagnostic biomarkers for differentiating between early-stage small cell lung cancer (SCLC) and early-stage non-small cell lung cancer (NSCLC). We compared the miRNA profiles of plasma-derived sEVs from healthy individuals, patients with early-stage SCLC and patients with early-stage NSCLC. Next-generation sequencing was used to screen for differentially expressed miRNAs (DEMs). Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were used to predict the potential functions of these DEMs. Weighted gene coexpression network analysis (WGCNA) was used to identify the different pathology-related miRNA modules. We found that 22 DEMs were significantly different among healthy individuals, patients with early-stage SCLC, and patients with early-stage NSCLC. We selected six representative DEMs for validation by qRT‒PCR, which confirmed that miRNA-483-3p derived from plasma sEVs could be used as a potential biomarker for the diagnosis of early-stage SCLC, miRNA-152-3p and miRNA-1277-5p could be used for the diagnosis of early-stage NSCLC respectively.

Ceramide Kinase Inhibition Drives Ferroptosis and Sensitivity to Cisplatin in Mutant KRAS Lung Cancer by Dysregulating VDAC-Mediated Mitochondria Function

Ceramide kinase (CERK) is the mammalian lipid kinase from which the bioactive sphingolipid, ceramide-1-phosphate (C1P), is derived. CERK has been implicated in several promalignant phenotypes with little known as to mechanistic underpinnings. In this study, the mechanism of how CERK inhibition decreases cell survival in mutant (Mut) KRAS non-small cell lung cancer (NSCLC), a major lung cancer subtype, was revealed. Specifically, NSCLC cells possessing a KRAS mutation were more responsive to inhibition, downregulation, and genetic ablation of CERK compared with those with wild-type (WT) KRAS regarding a reduction in cell survival. Inhibition of CERK induced ferroptosis in Mut KRAS NSCLC cells, which required elevating VDAC-regulated mitochondria membrane potential (MMP) and the generation of cellular reactive oxygen species (ROS). Importantly, through modulation of VDAC, CERK inhibition synergized with the first-line NSCLC treatment, cisplatin, in reducing cell survival and in vivo tumor growth. Further mechanistic studies indicated that CERK inhibition affected MMP and cell survival by limiting AKT activation and translocation to mitochondria, and thus, blocking VDAC phosphorylation and tubulin recruitment.

IMPLICATIONS

Our findings depict how CERK inhibition may serve as a new key point in combination therapeutic strategy for NSCLC, specifically precision therapeutics targeting NSCLC possessing a KRAS mutation.

Protective role of zinc in the pathogenesis of respiratory diseases

Respiratory diseases remain a major cause of morbidity and mortality worldwide. An imbalance of zinc, an essential trace element, is associated with a variety of lung diseases. We reviewed and summarized recent research (human subjects, animal studies, in vitro studies) on zinc in respiratory diseases to explore the protective mechanism of zinc from the perspective of regulation of oxidative stress, inflammation, lipid metabolism, and apoptosis. In the lungs, zinc has anti-inflammatory, antioxidant, and antiviral effects; can inhibit cancer cell migration; can regulate lipid metabolism and immune cells; and exerts other protective effects. Our comprehensive evaluation highlights the clinical and experimental effects of zinc in the pathogenesis of respiratory diseases. Our analysis also provides insight into the clinical application of zinc-targeted therapy for respiratory diseases.

Anesthetic propofol enhances cisplatin-sensitivity of non-small cell lung cancer cells through N6-methyladenosine-dependently regulating the miR-486-5p/RAP1-NF-κB axis

BACKGROUND

Drug resistance is a considerable challenge for chemotherapy in non-small cell lung cancer (NSCLC). Propofol, a commonly used intravenous anesthetics, has been reported to suppress the malignancy of various cancers. However, the effects of propofol on cisplatin (DDP) sensitivity in NSCLC and its molecular mechanisms have not been clearly clarified yet, and the present study aimed to resolve this problem.

METHODS

NSCLC cells were co-treated with propofol and DDP, Cell Counting kit-8 assay, colony formation assay and flow cytometry were conducted to test the role of propofol in regulating DDP-resistance in NSCLC. Next, through conducting quantitative real-time polymerase chain reaction, dual-luciferase gene reporter system and western blot, the responsible molecular axis in propofol regulating the DDP sensitivity in NSCLC was uncovered, and the function verification experiments were performed by transfection with the inhibitors or small interfering RNAs of those molecules.

RESULTS

Propofol suppressed cell viability, colony formation ability, tumorigenesis, and promoted cell apoptosis to enhance DDP-sensitivity in NSCLC in vitro and in vivo. Propofol increased miR-486-5p level in NSCLC cells and xenograft tumors tissues in a N6-methyladenosine (m6A)-dependent manner, thus inactivating the Ras-associated protein1 (RAP1)-NF-kappaB (NF-κB) axis. Propofol regulated the miR-486-5p/RAP1-NF-κB axis to improve DDP-sensitivity in NSCLC.

CONCLUSIONS

Taken together, this study firstly investigates the detailed molecular mechanisms by which propofol enhanced DDP-sensitivity in NSCLC cells, and a novel m6A-dependent miR-486-5p/RAP1-NF-κB axis is identified to be closely associated with the process.

Exosomes Derived from Tumor Cells Initiate Breast Cancer Cell Metastasis and Chemoresistance through a MALAT1-Dependent Mechanism

Background. Chemoresistance poses a great hindrance in the treatment of breast cancer (BC). Interestingly, exosome (Exo)-mediated transfer of long noncoding RNAs (lncRNAs) has been reported to regulate chemoresistance in diverse diseases. We herein investigate the potential role of lncRNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) transferred by BC cell-derived Exo in chemoresistance of BC cells. Methods. BC-related lncRNAs were identified. Exosomes were isolated and verified from BC cells. The expression patterns of MALAT1 were then examined in the adriamycin (ADR)-sensitive and resistant cells and the isolated Exo, followed by the analysis of the downstream microRNA (miRNA) of MALAT1. The role and mechanism of MALAT1 transmitted by BC cell-derived Exo in BC cell metastasis and chemoresistance were assessed. Results. MALAT1 was highly expressed in BC cells and their Exo. In addition, MALAT1 delivered by BC cell-derived Exo augmented the malignant properties and chemoresistance of BC cells. Mechanistically, MALAT1 bound to miR-1-3p and limited the miR-1-3p expression, which sequentially targeted the vasodilator-stimulated phosphoprotein (VASP) protein. Moreover, silencing of VASP inhibited the activation of the RAP1 member of RAS oncogene family (Rap1) signaling pathway, which led to the attenuation of BC cell malignant properties and chemoresistance. In vivo assay further validated the tumor-promoting effect of Exo-MALAT1 via regulation of the miR-1-3p/VASP/Rap1 axis. Conclusion. Collectively, MALAT1 loaded by BC cell-derived Exo can accelerate BC cell metastasis and chemoresistance via disruption of miR-1-3p-mediated inhibition of the VASP/Rap1 signaling axis.

Regulatory mechanism of α-hederin upon cisplatin sensibility in NSCLC at safe dose by destroying GSS/GSH/GPX2 axis-mediated glutathione oxidation-reduction system

Emerging studies showed that α-hederin induced autophagic cell death in different cancers via reactive oxygen species. Nevertheless, α-hederin role in non-small-cell lung cancer (NSCLC) remains unknown. So, the aim of this study was to explain whether ferroptosis is a therapeutic strategy to NSCLC, and to explore the effect of α-hederin on NSCLC ferroptosis. Current investigation found that α-hederin inhibited NSCLC cell proliferation, invasion, and migration in vitro and in vivo at toxic doses. The α-hederin treatment also increased NSCLC cell chemosensitivity to cisplatin and promoted ferroptosis and apoptosis at a safe dose. Proteomics, metabolomics, and high-throughput sequencing detection confirmed that α-hederin treatment downregulated glutathione peroxidase 2 (GPX2), and glutathione synthase (GSS) expression suppressed the synthesis of glutathione (GSH), which destroyed the GSH redox system. Eventually, it led to ferroptosis, apoptosis, and membrane permeabilization in NSCLC. Taken together, the study provided molecular data to confirm that α-hederin induced ferroptosis, apoptosis, and membrane permeabilization in NSCLC by destroying the GSS/GSH/GPX2 axis-mediated GSH oxidation-reduction system at a safe and low-toxicity dose.

Timosaponin AIII Suppresses RAP1 Signaling Pathway to Enhance the Inhibitory Effect of Paclitaxel on Nasopharyngeal Carcinoma

Although PTX has been identified as an effective drug for nasopharyngeal carcinoma (NPC) therapy, it has serious side effects in the human body. Previous studies have shown that timosaponin AIII (TSAIII) can inhibit the malignant progression of NPC cells. This study investigated the active mechanism of the combination of TSAIII and paclitaxel (PTX) on NPC. Cellular viability, apoptosis, apoptotic factors, and RAP1 signaling regulators were detected in the PNC cells (CNE-1 and HNE-2) and the subcutaneous CNE-1 transplanted nude mice treated with PTX or/and TSAIII. The results showed that TSAIII notably strengthened the inhibitory effect of PTX on the proliferation of NPC cells CNE-1 and HNE-2; upregulated the expression of Bax B-cell lymphoma 2 (Bcl-2)/Bcl-xL-associated death promoter (Bad), and Ras-associated protein1 (RAP1) GTPase activating protein (Rap1GAP); inhibited the level of Bcl-2, RAP1, and Ras guanine nucleotide releasing protein (RasGRP2); and significantly enhanced the promoting effect of PTX on apoptosis in the CNE-1 and HNE-2 cells. Besides, TSAIII strengthened the inhibitory effect of PTX on xenograft tumor in nude mice without adverse reactions. In conclusion, the combination administration of TSAIII and PTX had a significantly therapeutic effect on NPC and avoided the PTX's side effects, which may have acted as a new direction for the study of therapeutic approaches for NPC clinically.

OLFM4 depletion sensitizes gallbladder cancer cells to cisplatin through the ARL6IP1/caspase-3 axis

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OLFM4 is involved in development of gallbladder cancer.

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Depletion of OLFM4 sensitizes gallbladder cancer cells to cisplatin by regulating apoptosis.

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Low expression of OLFM4 in GBC patients indicates longer survival.

Background

Gallbladder cancer (GBC) is a highly lethal malignancy that carries an extremely poor prognosis due to its chemoresistant nature. Cisplatin (CDDP) is a first-line chemotherapeutic for GBC; however, patients experienced no benefit when treated with CDDP alone. The underlying mechanisms of CDDP resistance in GBC remain largely unknown.

Methods

Agilent mRNA microarray analysis was performed between paired GBC and paracarcinoma to explore differentially expressed genes that might underlie drug resistance. Gene Set Enrichment Analysis (GSEA) was employed to identify key genes mediating CDDP resistance in GBC, and immunohistochemistry was performed to validate protein expression and test correlations with clinicopathological features. In vitro and in vivo functional assays were performed to investigate the proteins’ roles in CDDP resistance.

Results

Olfactomedin 4 (OLFM4) was differentially expressed between GBC and paracarcinoma and had the highest rank metric score in the GSEA. OLFM4 expression was increasingly upregulated from chronic cholecystitis to GBC in clinical tissue samples, and OLFM4 depletion decreased GBC cell proliferation and invasion. Interestingly, downregulation of OLFM4 reduced ARL6IP1 (antiapoptotic factor) expression and sensitized GBC cells to CDDP both in vitro and in vivo. The evidence indicated that CDDP could significantly increase Bax and Bad expression and activate caspase-3 cascade in OLFM4-depleted GBC cells through ARL6IP1. Clinically, lower OLFM4 expression was associated with good prognosis of GBC patients.

Conclusions

Our results suggest that OLFM4 is an essential gene that contributes to GBC chemoresistance and could serve as a prognostic biomarker for GBC. Importantly, OLFM4 could be a potential chemotherapeutic target.

RAP1/TERF2IP-A Multifunctional Player in Cancer Development

Simple Summary

RAP1 (TERF2IP) is a member of the shelterin complex that protects telomeric DNA and plays a critical role in maintaining chromosome stability. However, mammalian RAP1 was recently found to have additional functions apart from telomeres, acting as a regulator of the NF-κB pathway and transcription factor, and has been suggested that they have putative roles in cancer development. Here, we focus on the main roles of RAP1 in different mechanisms of oncogenesis, progression, and chemoresistance, and consider the clinical significance of findings about its regulation and biological functions.

Abstract

Mammalian RAP1 (TERF2IP), the most conserved shelterin component, plays a pleiotropic role in the regulation of a variety of cellular processes, including cell metabolism, DNA damage response, and NF-κB signaling, beyond its canonical telomeric role. Moreover, it has been demonstrated to be involved in oncogenesis, progression, and chemoresistance in human cancers. Several mutations and different expression patterns of RAP1 in cancers have been reported. However, the functions and mechanisms of RAP1 in various cancers have not been extensively studied, suggesting the necessity of further investigations. In this review, we summarize the main roles of RAP1 in different mechanisms of cancer development and chemoresistance, with special emphasis on the contribution of RAP1 mutations, expression patterns, and regulation by non-coding RNA, and briefly discuss telomeric and non-telomeric functions.

Cyclometalated Ru(II)-isoquinoline complexes overcome cisplatin resistance of A549/DDP cells by downregulation of Nrf2 via Akt/GSK-3β/Fyn pathway

Both ruthenium (Ru) and isoquinoline (IQ) compounds are regarded as potential anticancer drug candidates. Here, we report the synthesis and characterization of three novel cyclometalated Ru(II)-isoquinoline complexes: RuIQ-3, RuIQ-4, and RuIQ-5, and evaluation of their in vitro cytotoxicities against a panel of cell lines including A549/DDP, a cisplatin-resistant human lung cancer cell line. A549/DDP 3D multicellular tumor spheroids (MCTSs) were also used to detect the drug resistance reversal effect of Ru(II)-IQ complexes. Our results indicated that the cytotoxic activities against cancer cells of Ru(II)-IQ complexes, especially RuIQ-5, were superior compared with cisplatin. In addition, RuIQ-5 exhibited low toxicity towards both normal HBE cells in vitro and zebrafish embryos in vivo. Further investigation on cellular mechanism of action indicated that after absorption by A549/DDP cells, RuIQ-5 was mainly distributed in the nucleus, which is different from cisplatin. Besides, RuIQ-5 could induce apoptosis through mitochondrial dysfunction, reactive oxygen species (ROS) accumulation, ROS-mediated DNA damage, and cycle arrest at both S and G2/M phases. Moreover, RuIQ-5 could inhibit the overexpression of Nrf2 through regulation of Akt/GSK-3β/Fyn signaling pathway and hindering the nuclear translocation of Nrf2. Based on these findings, we firmly believe that the studied Ru(II)-IQ complexes hold great promise as anticancer therapeutics with high effectiveness and low toxicity.

Ras Family of Small GTPases in CRC: New Perspectives for Overcoming Drug Resistance

Colorectal cancer remains among the cancers with the highest incidence, prevalence, and mortality worldwide. Although the development of targeted therapies against the EGFR and VEGFR membrane receptors has considerably improved survival in these patients, the appearance of resistance means that their success is still limited. Overactivation of several members of the Ras-GTPase family is one of the main actors in both tumour progression and the lack of response to cytotoxic and targeted therapies. This fact has led many resources to be devoted over the last decades to the development of targeted therapies against these proteins. However, they have not been as successful as expected in their move to the clinic so far. In this review, we will analyse the role of these Ras-GTPases in the emergence and development of colorectal cancer and their relationship with resistance to targeted therapies, as well as the status and new advances in the design of targeted therapies against these proteins and their possible clinical implications.

RAP1 moonlights to activate NF-κB and Notch in ALT

Cancer cells activate either telomerase or telomere recombination (ALT) to maintain telomere length and achieve immortalization. In this issue of Science Signaling, Robinson et al. reveal an unanticipated role of the protein SLX4IP in the SUMOylation of RAP1, which enhances its extratelomeric function in activating an NF-κB-Notch signaling axis that favors ALT.

Kinesin family member 2A promotes cancer cell viability, mobility, stemness, and chemoresistance to cisplatin by activating the PI3K/AKT/VEGF signaling pathway in non-small cell lung cancer

Kinesin family member 2A (KIF2A), a member of the kinesin-13 protein family that functions as a regulator in mitosis, neuron branch extension, etc., is reported to be involved in the pathogenesis of multiple cancers. This study assessed KIF2A effects on cancer cell functions and sensitivity to chemotherapy and its interaction with PI3K/AKT/VEGF signaling when mediating cancer cell functions, and chemosensitivity in non-small cell lung cancer (NSCLC). Human bronchial epithelial cell line BEAS-2B and human NSCLC cell lines NCI-H1299, NCI-H385, NCI-H1650, and A549 were used. The KIF2A and negative control (NC) overexpression plasmids were transfected into A549 cells; KIF2A and NC knock-down plasmids were transfected into NCI-H1299 cells. Rescue experiments were conducted by transfecting PI3K and NC knock-down plasmids into KIF2A overexpression A549 cells and transfecting PI3K and NC overexpression plasmids into KIF2A knock-down NCI-H1299 cells. Proliferation, apoptosis, migration, invasion, CD133⁺ proportion, sensitivity to chemotherapeutics, and PI3K/AKT/VEGF pathway were assessed. KIF2A mRNA and protein expression levels were elevated in NCI-H1299, NCI-H385, NCI-H1650, and A549 cells compared to BEAS-2B cells. KIF2A overexpression elevated proliferation, migration, invasion, stemness, and resistance to cisplatin but did not affect apoptosis or resistance to pemetrexed in A549 cells. Furthermore, KIF2A knock-down repressed proliferation, migration, invasion, stemness, and resistance to cisplatin, but not to pemetrexed, and it enhanced apoptosis in NCI-H1299 cells. Rescue experiments showed that the PI3K/AKT/VEGF pathway compensated for KIF2A effects on cell functions and sensitivity to cisplatin in A549 and NCI-H1299 cells. In conclusion, KIF2A advocates NSCLC cell viability, mobility, stemness, and chemoresistance to cisplatin by activating the PI3K/AKT/VEGF signaling pathway.

Exosomal miR-4443 promotes cisplatin resistance in non-small cell lung carcinoma by regulating FSP1 m6A modification-mediated ferroptosis

AIMS

Exosomal transfer of miRNAs affects recipient cell proliferation and chemoresistance. Here, we aimed to investigate the role of exosomal miRNAs in controlling cisplatin resistance in non-small cell lung carcinoma (NSCLC).

MAIN METHODS

Paired tumor and normal tissue-derived exosomes were collected from NSCLC patients with low or high responsiveness to cisplatin treatment. The results showed that the microRNA-4443 (miR-4443) level was upregulated in cisplatin-resistant NSCLC tumor tissue-derived exosomes compared with cisplatin-sensitive tissue-derived exosomes. Cisplatin-resistant cells (A549-R) were generated from the parental cells (A549-S). Resistant exosomes conferred cisplatin resistance by transferring miR-4443 to sensitive cells. Moreover, overexpression of miR-4443 inhibited FSP1-mediated ferroptosis induced by cisplatin treatment in vitro and enhanced tumor growth in vivo.

KEY FINDINGS

Through bioinformatics analysis and luciferase assays, METTL3 was confirmed as a direct target gene of miR-4443. Further mechanistic analysis showed that miR-4443 regulated the expression of FSP1 in an m6A manner via METLL3.

SIGNIFICANCE

Our findings provide more in-depth insight into the chemoresistance of NSCLC and support the therapeutic potential of targeting ferroptosis.

Integrated analysis of DNA methylation and mRNA expression profiles to identify key genes in head and neck squamous cell carcinoma

DNA methylation has been demonstrated to play significant roles in the etiology and pathogenesis of head and neck squamous cell carcinoma (HNSCC). In the present study, methylation microarray dataset (GSE87053) and gene expression microarray dataset (GSE23558) were downloaded from GEO database and analyzed through R language. A total of 255 hypermethylated-downregulated genes and 114 hypomethylated-upregulated genes were finally identified. Functional enrichment analyses were performed and a comprehensive protein–protein interaction (PPI) network was constructed. Subsequently, the top ten hub genes selected by Cytoscape software were subjected to further analyses. It was illustrated that the expression level of CSF2, CTLA4, ETS1, PIK3CD, and CFTR was intimately associated with HNSCC. Survival analysis suggested that CTLA4 and FGFR2 could serve as effective independent prognostic biomarkers for HNSCC patients. Overall, our study lay a groundwork for further investigation into the underlying molecular mechanisms in HNSCC carcinogenesis, providing potential biomarkers and therapeutic targets for HNSCC.

The sesquiterpene lactone eupatolide induces apoptosis in non-small cell lung cancer cells by suppressing STAT3 signaling

We aimed to evaluate the role of a natural sesquiterpene lactone, eupatolide, in non-small-cell lung cancer (NSCLC) and further explore its underlying mechanism on regulating the activation of signal transducer and activator of transcription 3 (STAT3), which is thought to have carcinogenic function in a variety of malignancies including lung cancer. Cell survival was measured by Cell Counting Kit-8 assay. in vivo experiments were performed by inoculating NSCLC cells into nude mice. Western blot and qRT-PCR were applied to detect the activation level of STAT3 and the mRNA levels of anti-apoptotic markers. The cell apoptosis was measured by Annexin V-FITC/PI Apoptosis Detection Kit. Our results showed that eupatolide suppressed the survival of NSCLC cells in a dose and time dependent manner. Furthermore, eupatolide increased the anti-tumor activity of the chemotherapeutic drugs cisplatin and 5-Fluoracil (5-FU). The xenograft study revealed that eupatolide suppressed tumor growth of NSCLC cells in vivo. Furthermore, eupatolide induced apoptosis by suppressing the activation of STAT3 in NSCLC cells. Sustained activation or knockdown of STAT3 suppressed and enhanced the activity of eupatolide, respectively. This paper is the first to report that eupatolide could effectively inhibit NSCLC progression, suggesting that eupatolide might be utilized as a novel STAT3 inhibitor for treating NSCLC.

A Non-genetic Mechanism Involving the Integrin β4/Paxillin Axis Contributes to Chemoresistance in Lung Cancer

Tumor heterogeneity and cisplatin resistance are major causes of tumor relapse and poor survival. Here, we show that in lung cancer, interaction between paxillin (PXN) and integrin β4 (ITGB4), components of the focal adhesion (FA) complex, contributes to cisplatin resistance. Knocking down PXN and ITGB4 attenuated cell growth and improved cisplatin sensitivity, both in 2D and 3D cultures. PXN and ITGB4 independently regulated expression of several genes. In addition, they also regulated expression of common genes including USP1 and VDAC1, which are required for maintaining genomic stability and mitochondrial function, respectively. Mathematical modeling suggested that bistability could lead to stochastic phenotypic switching between cisplatin-sensitive and resistant states in these cells. Consistently, purified subpopulations of sensitive and resistant cells re-created the mixed parental population when cultured separately. Altogether, these data point to an unexpected role of the FA complex in cisplatin resistance and highlight a novel non-genetic mechanism.

The Role of Ras-Associated Protein 1 (Rap1) in Cancer: Bad Actor or Good Player?

Metastasis is known as the most life-threatening event in cancer patients. In principle, the immune system can prevent tumor development. However, dysfunctional T cells may fail to eliminate the tumor cells effectively and provide additional survival advantages for tumor proliferation and metastasis. Constitutive activation of Ras-associated protein1 (Rap1) has not only led to T cell anergy, but also inhibited autophagy and supported cancer progression through various oncogenic events. Inhibition of Rap1 activity with its negative regulator, Rap1GAP, impairs tumor progression. However, active Rap1 reduces tumor invasion in some cancers, indicating that the pleiotropic effects of Rap1 signaling in cancers could be cancer-specific. All in all, targeting Rap1 signaling and its regulators could potentially control carcinogenesis, metastasis, chemoresistance and immune evasion. Rap1GAP could be a promising therapeutic target in combating cancer.

Development of an Immune-Related Risk Signature for Predicting Prognosis in Lung Squamous Cell Carcinoma

Lung squamous cell carcinoma (LSCC) is the most common subtype of non-small cell lung cancer. Immunotherapy has become an effective treatment in recent years, while patients showed different responses to the current treatment. It is vital to identify the potential immunogenomic signatures to predict patient' prognosis. The expression profiles of LSCC patients with the clinical information were downloaded from TCGA database. Differentially expressed immune-related genes (IRGs) were extracted using edgeR algorithm, and functional enrichment analysis showed that these IRGs were primarily enriched in inflammatory- and immune-related processes. "Cytokine-cytokine receptor interaction" and "PI3K-AKT signaling pathway" were the most enriched KEGG pathways. 27 differentially expressed IRGs were significantly correlated with the overall survival (OS) of patients using univariate Cox regression analysis. A prognostic risk signature that comprises seven IRGs (GCCR, FGF8, CLEC4M, PTH, SLC10A2, NPPC, and FGF4) was developed with effective predictive performance by multivariable Cox stepwise regression analysis. Most importantly, the signature could be an independent prognostic predictor after adjusting for clinicopathological parameters, and also validated in two independent LSCC cohorts (GSE4573 and GSE17710). Potential molecular mechanisms and tumor immune landscape of these IRGs were investigated through computational biology. Analysis of tumor infiltrating lymphocytes and immune checkpoint molecules revealed distinct immune landscape in high- and low-risk group. The study was the first time to construct IRG-based immune signature in the recognition of disease progression and prognosis of LSCC patients.

LncRNA KCNQ1OT1 is a key factor in the reversal effect of curcumin on cisplatin resistance in the colorectal cancer cells

The development of cisplatin resistance is a common cause of cancer recurrence in colorectal cancer (CRC). Though many studies have reported the oncogenic function of long non-coding RNA (LncRNA) KCNQ1OT1 in multiple cancers, few studies explored its role in cisplatin resistance of CRC. Curcumin is a natural phenolic compound extracted from turmeric, which can effectively suppress cisplatin resistance in CRC. This study aims to expound the role of KCNQ1OT1 in cisplatin resistance in CRC cells and whether KCNQ1OT1 participates in the reversal effect of curcumin on cisplatin resistance in CRC. The interplay between KCNQ1OT1 and miR-497 was determined using RNA pull-down assay and dual-luciferase reporter gene assay. The combination of B-cell lymphoma 2 (Bcl-2) and miR-497 was confirmed using dual-luciferase reporter gene assay. Compared with CRC cell line HCT8, the cisplatin-resistant CRC cell line HCT8/DDP exhibited a higher expression level of KCNQ1OT1. Functionally, the silence of KCNQ1OT1 suppressed proliferation and boosted apoptosis in HCT8/DDP cells. Subsequently, we found that KCNQ1OT1 could act as a sponge of miR-497 and remove the suppressive effect of miR-497 on Bcl-2 expression. Curcumin treatment restrained proliferation and facilitated apoptosis in HCT8/DDP cells. While KCNQ1OT1 overexpression removed the effect of curcumin on HCT8/DDP cells via miR-497/ Bcl-2 axis. Finally, the in vivo experiments showed that the inhibitory effect of curcumin on the growth of cisplatin-resistant CRC cells was reserved by the ectopic expression of KCNQ1OT1. In conclusion, KCNQ1OT1 aggravated cisplatin resistance in CRC cells via the miR-497/Bcl-2 axis. Administration of curcumin could effectively downregulate KCNQ1OT1 expression, thus reversing cisplatin resistance in CRC cells.

The Fire Within: NF-κB Involvement in Non-Small Cell Lung Cancer

Thirty-four years since its discovery, NF-κB remains a transcription factor with great potential for cancer therapy. However, NF-κB-targeted therapies have yet to find a way to be clinically translatable. Here, we focus exclusively on the role of NF-κB in non-small cell lung cancer (NSCLC) and discuss its contributing effect on cancer hallmarks such as inflammation, proliferation, survival, apoptosis, angiogenesis, epithelial-mesenchymal transition, metastasis, stemness, metabolism, and therapy resistance. In addition, we present our current knowledge of the clinical significance of NF-κB and its involvement in the treatment of patients with NSCLC with chemotherapy, targeted therapies, and immunotherapy.

Berberine chloride suppresses non-small cell lung cancer by deregulating Sin3A/TOP2B pathway in vitro and in vivo

PURPOSE

Berberine chloride (BBC) is a well-known plant isoquinoline alkaloid derived from Berberis aristata. In this study, we aim to explore the effect of BBC on non-small cell lung cancer (NSCLC), and further expound the underlying mechanism of BBC induces NSCLC cell death in vitro and in vivo.

METHODS

CCK-8 assay and colony formation assay were used to test the viability and colony formation ability of NSCLC cells. Apoptosis analysis was used to analyze the apoptotic cells. siRNAs were utilized to disturb the expression of Sin3A. qPCR and Western blot analysis were employed to determine mRNA and protein levels of related genes and proteins. Tumor xenografts model was used for in vivo detection.

RESULTS

BBC inhibited the proliferation and colony formation of human NSCLC cells in a dose- and time-dependent manner. In addition, BBC induced DNA double-stranded breaks (DSBs) through downregulating TOP2B level, leading to apoptosis in human NSCLC cells. The Chip-seq data of A549 cells obtained from the ENCODE consortium indicate that Sin3A binds on the promoters of TOP2B. Knockdown of Sin3A led to downregulation of TOP2B in human NSCLC cells. Furthermore, BBC decreased Sin3A expression and shortened the half-life of Sin3A, results in downregulation of TOP2B in human NSCLC cells.

CONCLUSION

In this study, we demonstrated a new mechanism that BBC suppresses human NSCLC by deregulating Sin3A/TOP2B pathway, leading to DNA damage and apoptosis in human NSCLC in vitro and in vivo.

Role of CC Chemokines Subfamily in the Platinum Drugs Resistance Promotion in Cancer

Cancer is a significant medical issue, being one of the main causes of mortality around the world. The therapies for this pathology depend on the stage in which the cancer is found, but it is usually diagnosed at an advanced stage in which the treatment is chemotherapy. Platinum drugs are among the most commonly used in therapy, unfortunately, one of the main obstacles to this treatment is the development of chemoresistance, which is the ability of cancer cells to evade the effects of drugs. Although some molecular mechanisms involved in resistance to platinum drugs are described, elucidation is still required of others. Secretion of inflammatory mediators such as cytokines and chemokines, by tumor microenvironment components or tumor cells, show direct influence on proliferation, metastasis and progression of cancer and are related to chemoresistance and poor prognosis. In this review, the general mechanisms associated with resistance to platinum drugs, inflammation on cancer development and chemoresistance in various types of cancer will be approached with special emphasis on the current history of CC chemokines subfamily-mediated chemoresistance.

Roles of TP53 gene in the development of resistance to PI3K inhibitor resistances in CRISPR-Cas9-edited lung adenocarcinoma cells

The mutation rates of tumor suppressor protein p53 gene (TP53) are high in lung adenocarcinoma and promote the development of acquired drug resistance. The present study evaluated the p53-dependent role in lung cancer cell sensitivity to PI3K-specific inhibitors, PI3K-associated inhibitors, PI3K-non-related inhibitors, and protein-based stimuli using designed p53 mutation. We found that the deletion of p53 key regions from amino acid 96 to 393 with the CRISPR-Cas9 altered multi-dimensional structure and sequencing of p53, probably leading the secondary changes in chemical structures and properties of PI3K subunit proteins or in interactions between p53 and PI3K isoform genes. The p53-dependent cell sensitivity varied among target specificities, drug chemical properties, mechanism-specific signal pathways, and drug efficacies, independently upon the size of molecules. The effects of the designed p53 mutation highly depend upon p53-involved molecular mechanisms in the cell. Our results indicate that lung cancer cell resistance to drug can develop with dynamic formations of p53 mutations changing the cell sensitivity. This may explain the real-time occurrence of cancer cell resistance to drug treatment, during which drugs may induce the new mutations of p53. Thus, it is important to dynamically monitor the formation of new mutations during the therapy and discover new drug resistance-specific targets.

Combination of Gentiana rhodantha and Gerbera anandria in the BL02 formula as therapeutics to non-small cell lung carcinoma acting via Rap1/cdc42 signaling: A transcriptomics/ bio-informatics biological validation approach

BACKGROUND

Non-small cell lung cancer (NSCLC) ranks the most commonly diagnosed and highest mortality-leading cancer worldwide despite a variety of treatment strategies are available. The highly heterogeneous and aggressive property of NSCLC as well as its poor prognosis indicates the need for novel therapeutic targets identification. The objective of this study is to identify potential targets from the adjuvant herbal formula BL02 using a combined approach of high throughput transcriptomics and network pharmacology.

METHODS

The quality and stability of BL02 were assessed by UHPLC analysis. The inhibitory effect of BL02 on NSCLC was measured by in vivo orthotopic intrathoracic mouse model and in vitro cellular models. EGFR-mutant HCC827 and wild type A549 cell lines were employed. Transcriptomics analysis was introduced to profile the gene expression of NSCLC cells treated with BL02; Network pharmacology and molecular docking analyses predicted the interaction of compounds and NSCLC targets. Immuno-blotting and pull-down assays verified the putative targets.

RESULTS

The UHPLC analysis revealed that BL02 was relatively stable between batches of production and for 24 months of storage. Orally administration of BL02 was safe and effective to inhibit pulmonary NSCLC growth in mice implanted with A549 and HCC827-generated tumors. BL02 exhibited relatively low cytotoxicity to NSCLC cells in vitro, but potently suppressed NSCLC cell motility. The transcriptomic analysis illustrated that EGFR and cellular adhesion-related signaling is involved in BL02 action. Further bioinformatics analysis validated BL02 activity is mediated by cdc42-regulated signaling. BL02 depolymerized the actin cytoskeleton through suppressing cdc42 and deactivating its upstream molecule Rap1. These effects may be primarily mediated by the direct binding of 5-methylcoumarin-4-cellobioside and mangiferin from BL02 to Rap1 protein.

CONCLUSION

Our study proposes an integration model of experimental, transcriptomic and bioinformatics analyses in the identification of novel therapeutic target of NSCLC from an adjuvant herbal formula BL02. Our findings revealed that inhibition of Rap1/cdc42 signaling by active compounds 5-methylcoumarin-4-cellobioside and mangiferin from BL02 might be potentially effective therapy for NSCLC.

SHARPIN Promotes Melanoma Progression via Rap1 Signaling Pathway

SHARPIN, as a tumor-associated gene, is involved in the metastatic process of many kinds of tumors. Herein, we studied the function of Shank-associated RH domain interacting protein (SHARPIN) in melanoma metastasis and the relevant molecular mechanisms. We found that SHARPIN expression was increased in melanoma tissues and activated the process of proliferation, migration, and invasion in vitro and in vivo, resulting in a poor prognosis of the disease. Functional analysis demonstrated that SHARPIN promoted melanoma migration and invasion by regulating Ras-associated protein-1(Rap1) and its downstream pathways, including p38 and JNK/c-Jun. Rap1 activator (8-pCPT-2'-O-Me-cAMP) and inhibitor (ESI-09 and farnesylthiosalicylic acid-amide) treatments could partially rescue invasion and migration of tumor cells. Additionally, SHARPIN expression in cell lines and public datasets also indicated that molecules other than BRAF and N-RAS may contribute to SHARPIN activation. In conclusion, our broad-in-depth work suggests that SHARPIN promotes melanoma development via p38 and JNK/c-Jun pathways through upregulation of Rap1 expression.

IL-25 promotes cisplatin resistance of lung cancer cells by activating NF-κB signaling pathway to increase of major vault protein

As an inflammatory factor, IL‐25 has been studied in variouscancers, but it is rarely reported in cancer chemotherapy resistance. Major vault protein (MVP), as a gene associated with lung multidrug resistance, is associated with multiple chemotherapy resistances of lung cancer. However, the relationship between IL‐25 and MVP in lung cancer cells has not been studied. In this study, we found that both IL‐25 and MVP were elevated expressed in cisplatin‐resistant lung adenocarcinoma cell line (A549/CDDP). Silencing of IL‐25 resulted in down‐regulation of MVP expression and reduced cisplatin tolerance of A549/CDDP cells. Overexpression of IL‐25 resulted in increase of MVP expression and the cisplatin tolerance in A549 cells. In addition, we found that the extracellular IL‐25 could stimulate the expression of MVP and activate the NF‐κB signaling pathway. Further, animal models also confirmed that IL‐25 reduced the sensitivity of xenografts to chemotherapy. Taken together, we believe that the up‐regulation of IL‐25 induces MVP expression contributing to chemotherapy resistances of lung cancer cells. Our findings suggest that interference the expression of IL‐25 might be potential treatment strategies for the clinical reversing the chemotherapy resistance.

Inhibition of EGFR signaling with Spautin-1 represents a novel therapeutics for prostate cancer

Background

Prostate cancer (PCa) remains a challenge worldwide. Due to the development of castration-resistance, traditional first-line androgen deprivation therapy (ADT) became powerlessness. Epidermal growth factor receptor (EGFR) is a well characterized therapeutic target to treat colorectal carcinoma and non-small cell lung cancer. Increasing studies have unraveled the significance of EGFR and its downstream signaling in the progression of castration-resistant PCa.

Method

MTS, colony formation and Edu staining assays were used to analyze the cell proliferation of PCa cells. Flow cytometry was used to analyze PCa cell cycle distribution and cell apoptosis. Western blot was used to measure the expression of key proteins associated with cell cycle progression, apoptosis and EGFR signaling pathways. Transfection of exogenous small interfering RNA (siRNA) or plasmid was used to intervene specific gene expression. Nude mouse model was employed to test the in vivo effect of Spautin-1.

Results

The current study reveals that Spautin-1, a known inhibitor of ubiquitin-specific peptidase 10 (USP10) and USP13, inhibits EGFR phosphorylation and the activation of its downstream signaling. Inhibition of EGFR signaling induced by Spautin-1 leads to cell cycle arrest and apoptosis of PCa in a USP10/USP13 independent manner. The application of Spautin-1 reduces the expression of glucose transporter 1 (Glut1) and dramatically induces cell death under glucose deprivation condition. In vivo experiments show a potent anti-tumor effect of Spautin-1 alone and in combination with Enzalutamide.

Conclusion

This study demonstrates the therapeutic potential of EGFR signaling inhibition by the use of Spautin-1 for PCa treatment.

Electronic supplementary material

The online version of this article (10.1186/s13046-019-1165-4) contains supplementary material, which is available to authorized users.

Next-Generation Sequencing Analysis of mRNA Profile in Cisplatin-Resistant Gastric Cancer Cell Line SGC7901

BACKGROUND Cisplatin-resistant gastric cancer (GC) occurs in patients with GC treated with cisplatin-based chemotherapy, which results in disease progression and early recurrence during the treatment. MATERIAL AND METHODS To understand the initiation and developmental mechanism underlying cisplatin-resistant GC, we developed cisplatin-resistant SGC7901 cells (SGC7901/DDP) from the parental cells (SGC7901/S) by continuous exposure to increasing concentrations of cisplatin and subjected these 2 cell lines to RNA sequencing analysis. The data were verified by quantitative polymerase chain reaction and their functional role was evaluated by cell counting kit 8 assay and cell apoptosis and cell cycle flow cytometric analysis. Bioinformatics analysis was performed to classify the differentially-expressed genes (DEGs) involved in the development of cisplatin resistance. RESULTS In comparison with SGC7901/S cells, SGC7901/DDP cells showed a total of 3165 DEGs (2014 upregulated and 1151 downregulated, fold change ≥2, and adjusted P value <0.001). qRT-PCR confirmed the reliability of the RNA sequencing results. Depletion of the top 5 upregulated mRNAs reversed the resistant index, increased apoptotic SGC7901/DDP cells, and arrested the cells at G2/M phase. Gene ontology analysis revealed that the DEGs mainly regulate metabolic process, immune system, locomotion, cell adhesion, cell growth, cell death, cytoskeleton organization, cell binding, signal transducing activity, and antioxidant activity. Kyoto Encyclopedia of Genes and Genomes analysis showed that the DEGs were mainly involved in the PI3K-Akt signaling pathway, Rap1 signaling pathway, proteoglycans in cancer, regulation of actin cytoskeleton, and pathways in cancer. CONCLUSIONS The present study is the first to interrogate mRNAs profiles in human GC cells with cisplatin resistance using RNA sequencing, which may assist in discovering potential therapeutic targets for cisplatin-resistant GC patients.

Telomere-dependent and telomere-independent roles of RAP1 in regulating human stem cell homeostasis

RAP1 is a well-known telomere-binding protein, but its functions in human stem cells have remained unclear. Here we generated RAP1-deficient human embryonic stem cells (hESCs) by using CRISPR/Cas9 technique and obtained RAP1-deficient human mesenchymal stem cells (hMSCs) and neural stem cells (hNSCs) via directed differentiation. In both hMSCs and hNSCs, RAP1 not only negatively regulated telomere length but also acted as a transcriptional regulator of RELN by tuning the methylation status of its gene promoter. RAP1 deficiency enhanced self-renewal and delayed senescence in hMSCs, but not in hNSCs, suggesting complicated lineage-specific effects of RAP1 in adult stem cells. Altogether, these results demonstrate for the first time that RAP1 plays both telomeric and nontelomeric roles in regulating human stem cell homeostasis.

Differential Exosomic Proteomic Patterns and Their Influence in Resveratrol Sensitivities of Glioblastoma Cells

Glioblastoma multiforme (GBM) is the commonest primary brain malignancy with extremely poor prognosis. Resveratrol posseses anti-cancer effects, while GBM cells respond differently to it due to certain unknown reason(s). Because the tumor-derived exosomes are supposed to influence chemosensitivity, the exosomic proteins released from resveratrol-sensitive U251 and resveratrol-resistant glioblastoma LN428 cells are profiled before (N/Exo) and after drug treatment (Res/Exo) by label-free liquid chromatography-mass spectrometry (LC-MS). The therapeutic implications of the proteomic findings are estimated by gene ontology enrichment analysis (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG)-based bioinformatic analyses and further elucidated by exosome co-incubating. The results reveal that U251/N/Exo but not U251/Res/Exo enhances resveratrol sensitivity of resveratrol-resistant LN428 cells. The resveratrol sensitive properties of U251 cells are not altered by either LN428/N/Exo or LN428/Res/Exo. U251/N/Exo contains higher levels of chromatin silencing and epidermis development proteins, while U251/Res/Exo has more oxygen transport and G protein-coupled receptor. Both of LN428/N/Exo and LN428/Res/Exo are rich in the proteins related with nucleosome assembly, microtubule-based process and chromatin silencing. In conclusion, U251/N/Exo sensitizes LN428 cells to resveratrol via delivering drug sensitizing signals, suggesting the presence of additional factor(s) that may determine the resveratrol sensitivities of glioblastoma cells.

Thyrotroph embryonic factor is downregulated in bladder cancer and suppresses proliferation and tumorigenesis via the AKT/FOXOs signalling pathway

Objectives

Thyrotroph embryonic factor (TEF) plays an important role in several different processes in normal human cells; however, its function in malignant cells has not been fully elucidated.

Materials and methods

The mRNA levels of TEF in 408 bladder cancer (BC) samples from the Cancer Genome Atlas (TCGA) database were analysed in depth. Next, the expression of TEF in 7 BC cell lines was compared to that in normal bladder epithelial cells. The cell count, colony formation and anchorage‐independent growth assays as well as a nude mouse xenograft model were utilized to examine the effects of TEF on proliferation and tumorigenesis. Immunofluorescence staining, flow cytometry analysis and treatment with an AKT inhibitor were performed to explore the molecular regulation mechanisms of TEF in BC.

Results

Analysis of TCGA data indicated that TEF mRNA was decreased in BC samples compared to that in normal bladder epithelial cells and correlated with the poor survival of BC patients. Additional experiments verified that the mRNA and protein expression of TEF were significantly decreased in BC cells compared to that in normal bladder epithelial cells. Upregulation of TEF expression significantly retarded BC cell growth by inhibiting the G1/S transition via regulating AKT/FOXOs signalling.

Conclusion

Our results suggest that TEF might play an important role in suppressing BC cells proliferation and tumorigenesis.

A five-gene signature may predict sunitinib sensitivity and serve as prognostic biomarkers for renal cell carcinoma

Sunitinib resistance is, nowadays, the major challenge for advanced renal cell carcinoma patients. Illuminating the potential mechanisms and exploring effective strategies to overcome sunitinib resistance are highly desired. We constructed a reliable gene signature which may function as biomarkers for prediction of sunitinib sensitivity and clinical prognosis. The gene expression profiles were obtained from The Cancer Genome Atlas database. By performing GEO2R analysis, numerous differentially expressed genes (DEGs) were found to be associated with sunitinib resistance. To acquire more precise DEGs, we integrated three different microarray datasets. Functional analysis revealed that these DEGs were mainly involved in Rap1 signaling pathway, p53 signaling pathway and Ras signaling pathway. Then, top five hub genes, BIRC5, CD44, MUC1, TF, CCL5, were identified from protein-protein interaction (PPI) network. Sub-network analysis carried out by MCODE plugin revealed that key DEGs were related with PI3K-Akt signaling pathway, Rap1 signaling pathway and VEGF signaling pathway. Next, we established sunitinib-resistant OS-RC-2 and 786-O cell lines and validated the expression of five hub genes in cell lines. To further evaluate the potentials of five-gene signature for predicting clinical prognosis, we analyzed RCC patients with gene expressions and overall survival information from two independent patient datasets. The Kaplan-Meier estimated the OS of RCC patients in the low- and high-risk groups according to gene expression signature. Multivariate Cox regression analysis indicated that the prognostic power of five-gene signature was independent of clinical features. In conclusion, we developed a five-gene signature which can predict sunitinib sensitivity and OS for advanced RCC patients, providing novel insights into understanding of sunitinib-resistant mechanisms and identification of RCC patients with poor prognosis.