scholarly journals Hypoxia-Induced Intracellular and Extracellular Heat Shock Protein gp96 Increases Paclitaxel-Resistance and Facilitates Immune Evasion in Breast Cancer

2021 ◽  
Vol 11 ◽  
Author(s):  
Tian Tian ◽  
Jiguang Han ◽  
Jian Huang ◽  
Shangziyan Li ◽  
Hui Pang

BackgroundsHypoxia contributes to cancer progression, drug resistance and immune evasion in various cancers, including breast cancer (BC), but the molecular mechanisms have not been fully studied. Thus, the present study aimed to investigate this issue.MethodsThe paclitaxel-sensitive BC (PS-BC) cells were administered with continuous low-dose paclitaxel treatment to establish paclitaxel-resistant BC (PR-BC) cells. Exosomes were isolated/purified by using the commercial kit, which were observed by Transmission electron microscopy (TEM). Cell viability was measured by MTT assay, cell apoptosis was determined by flow cytometer (FCM). Gene expressions were respectively measured by Real-Time qPCR, Western Blot and immunofluorescence staining assay. The peripheral mononuclear cells (PBMCs) derived CD8+ T cells were obtained and co-cultured with gp96-containing exosomes, and cell proliferation was evaluated by EdU assay. ELISA was employed to measure cytokine secretion in CD8+ T cells’ supernatants.ResultsHSP gp96 was significantly upregulated in the cancer tissues and plasma exosomes collected from BC patients with paclitaxel-resistant properties. Also, continuous low-dose paclitaxel treatment increased gp96 levels in the descendent PR-BC cells and their exosomes, in contrast with the parental PS-BC cells. Upregulation of gp96 increased paclitaxel-resistance in PS-BC cells via degrading p53, while gp96 silence sensitized PR-BC cells to paclitaxel treatments. Moreover, PR-BC derived gp96 exosomes promoted paclitaxel-resistance in PS-BC cells and induced pyroptotic cell death in the CD8+ T cells isolated from human peripheral blood mononuclear cells (pPBMCs). Furthermore, we noticed that hypoxia promoted gp96 generation and secretion through upregulating hypoxia-inducible factor 1 (HIF-1), and hypoxia increased paclitaxel-resistance and accelerated epithelial-mesenchymal transition (EMT) in PS-BC cells.ConclusionsHypoxia induced upregulation of intracellular and extracellular gp96, which further degraded p53 to increase paclitaxel-sensitivity in BC cells and activated cell pyroptosis in CD8+ T cells to impair immune surveillance.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
S. Nishad ◽  
Pankaj Kumar Chauhan ◽  
R. Sowdhamini ◽  
Anu Ghosh

AbstractUnderstanding exposures to low doses of ionizing radiation are relevant since most environmental, diagnostic radiology and occupational exposures lie in this region. However, the molecular mechanisms that drive cellular responses at these doses, and the subsequent health outcomes, remain unclear. A local monazite-rich high level natural radiation area (HLNRA) in the state of Kerala on the south-west coast of Indian subcontinent show radiation doses extending from ≤ 1 to ≥ 45 mGy/y and thus, serve as a model resource to understand low dose mechanisms directly on healthy humans. We performed quantitative discovery proteomics based on multiplexed isobaric tags (iTRAQ) coupled with LC–MS/MS on human peripheral blood mononuclear cells from HLNRA individuals. Several proteins involved in diverse biological processes such as DNA repair, RNA processing, chromatin modifications and cytoskeletal organization showed distinct expression in HLNRA individuals, suggestive of both recovery and adaptation to low dose radiation. In protein–protein interaction (PPI) networks, YWHAZ (14-3-3ζ) emerged as the top-most hub protein that may direct phosphorylation driven pro-survival cellular processes against radiation stress. PPI networks also identified an integral role for the cytoskeletal protein ACTB, signaling protein PRKACA; and the molecular chaperone HSPA8. The data will allow better integration of radiation biology and epidemiology for risk assessment [Data are available via ProteomeXchange with identifier PXD022380].


2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A799-A799
Author(s):  
Dhiraj Kumar ◽  
Sreeharsha Gurrapu ◽  
Hyunho Han ◽  
Yan Wang ◽  
Seongyeon Bae ◽  
...  

BackgroundLong non-coding RNAs (lncRNAs) are involved in various biological processes and diseases. Malat1 (metastasis-associated lung adenocarcinoma transcript 1), also known as Neat2, is one of the most abundant and highly conserved nuclear lncRNAs. Several studies have shown that the expression of lncRNA Malat1 is associated with metastasis and serving as a predictive marker for various tumor progression. Metastatic relapse often develops years after primary tumor removal as a result of disseminated tumor cells undergoing a period of latency in the target organ.1–4 However, the correlation of tumor intrinsic lncRNA in regulation of tumor dormancy and immune evasion is largely unknown.MethodsUsing an in vivo screening platform for the isolation of genetic entities involved in either dormancy or reactivation of breast cancer tumor cells, we have identified Malat1 as a positive mediator of metastatic reactivation. To functionally uncover the role of Malat1 in metastatic reactivation, we have developed a knock out (KO) model by using paired gRNA CRISPR-Cas9 deletion approach in metastatic breast and other cancer types, including lung, colon and melanoma. As proof of concept we also used inducible knockdown system under in vivo models. To delineate the immune micro-environment, we have used 10X genomics single cell RNA-seq, ChIRP-seq, multi-color flowcytometry, RNA-FISH and immunofluorescence.ResultsOur results reveal that the deletion of Malat1 abrogates the tumorigenic and metastatic potential of these tumors and supports long-term survival without affecting their ploidy, proliferation, and nuclear speckles formation. In contrast, overexpression of Malat1 leads to metastatic reactivation of dormant breast cancer cells. Moreover, the loss of Malat1 in metastatic cells induces dormancy features and inhibits cancer stemness. Our RNA-seq and ChIRP-seq data indicate that Malat1 KO downregulates several immune evasion and stemness associated genes. Strikingly, Malat1 KO cells exhibit metastatic outgrowth when injected in T cells defective mice. Our single-cell RNA-seq cluster analysis and multi-color flow cytometry data show a greater proportion of T cells and reduce Neutrophils infiltration in KO mice which indicate that the immune microenvironment playing an important role in Malat1-dependent immune evasion. Mechanistically, loss of Malat1 is associated with reduced expression of Serpinb6b, which protects the tumor cells from cytotoxic killing by the T cells. Indeed, overexpression of Serpinb6b rescued the metastatic potential of Malat1 KO cells by protecting against cytotoxic T cells.ConclusionsCollectively, our data indicate that targeting this novel cancer-cell-initiated domino effect within the immune system represents a new strategy to inhibit tumor metastatic reactivation.Trial RegistrationN/AEthics ApprovalFor all the animal studies in the present study, the study protocols were approved by the Institutional Animal Care and Use Committee(IACUC) of UT MD Anderson Cancer Center.ConsentN/AReferencesArun G, Diermeier S, Akerman M, et al., Differentiation of mammary tumors and reduction in metastasis upon Malat1 lncRNA loss. Genes Dev 2016 Jan 1;30(1):34–51.Filippo G. Giancotti, mechanisms governing metastatic dormancy and reactivation. Cell 2013 Nov 7;155(4):750–764.Gao H, Chakraborty G, Lee-Lim AP, et al., The BMP inhibitor Coco reactivates breast cancer cells at lung metastatic sites. Cell 2012b;150:764–779.Gao H, Chakraborty G, Lee-Lim AP, et al., Forward genetic screens in mice uncover mediators and suppressors of metastatic reactivation. Proc Natl Acad Sci U S A 2014 Nov 18; 111(46): 16532–16537.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mohsin Ali Khan ◽  
Sahabjada Siddiqui ◽  
Imran Ahmad ◽  
Romila Singh ◽  
Durga Prasad Mishra ◽  
...  

AbstractAjwa dates (Phoenix dactylifera L.) have been described in traditional and alternative medicine to provide several health benefits, but their mechanism of apoptosis induction against human triple-negative breast cancer MDA-MB-231 cells remains to be investigated. In this study, we analyzed the phytoconstituents in ethanolic Ajwa Dates Pulp Extract (ADPE) by liquid chromatography-mass spectrometry (LC–MS) and investigated anticancer effects against MDA-MB-231 cells. LC–MS analysis revealed that ADPE contained phytocomponents belonging to classes such as carbohydrates, phenolics, flavonoids and terpenoids. MTT assay demonstrated statistically significant dose- and time-dependent inhibition of MDA-MB-231 cells with IC50 values of 17.45 and 16.67 mg/mL at 24 and 48 h, respectively. Hoechst 33342 dye and DNA fragmentation data showed apoptotic cell death while AO/PI and Annexin V-FITC data revealed cells in late apoptosis at higher doses of ADPE. More importantly, ADPE prompted reactive oxygen species (ROS) induced alterations in mitochondrial membrane potential (MMP) in ADPE treated MDA-MB-231 cells. Cell cycle analysis demonstrated that ADPE induced cell arrest in S and G2/M checkpoints. ADPE upregulated the p53, Bax and cleaved caspase-3, thereby leading to the downregulation of Bcl-2 and AKT/mTOR pathway. ADPE did not show any significant toxicity on normal human peripheral blood mononuclear cells which suggests its safe application to biological systems under study. Thus, ADPE has the potential to be used as an adjunct to the mainline of treatment against breast cancer.


2020 ◽  
Vol 22 (1) ◽  
pp. 274
Author(s):  
Claudia Curci ◽  
Angela Picerno ◽  
Nada Chaoul ◽  
Alessandra Stasi ◽  
Giuseppe De Palma ◽  
...  

Adult Renal Stem/Progenitor Cells (ARPCs) have been recently identified in the human kidney and several studies show their active role in kidney repair processes during acute or chronic injury. However, little is known about their immunomodulatory properties and their capacity to regulate specific T cell subpopulations. We co-cultured ARPCs activated by triggering Toll-Like Receptor 2 (TLR2) with human peripheral blood mononuclear cells for 5 days and 15 days and studied their immunomodulatory capacity on T cell subpopulations. We found that activated-ARPCs were able to decrease T cell proliferation but did not affect CD8+ and CD4+ T cells. Instead, Tregs and CD3+ CD4- CD8- double-negative (DN) T cells decreased after 5 days and increased after 15 days of co-culture. In addition, we found that PAI1, MCP1, GM-CSF, and CXCL1 were significantly expressed by TLR2-activated ARPCs alone and were up-regulated in T cells co-cultured with activated ARPCs. The exogenous cocktail of cytokines was able to reproduce the immunomodulatory effects of the co-culture with activated ARPCs. These data showed that ARPCs can regulate immune response by inducing Tregs and DN T cells cell modulation, which are involved in the balance between immune tolerance and autoimmunity.


2021 ◽  
Author(s):  
Ni Qiu ◽  
Huan Jin ◽  
Lulu Cui ◽  
Yong-tao Zhan ◽  
Hao-ming Xia ◽  
...  

Abstract Background: System paclitaxel-based chemotherapy is the first-line treatment regimen of defense against breast cancer, but inherent or acquired chemotherapy resistance remains a major obstacle in breast cancer therapy. Elucidating the molecular mechanism of chemoresistance is essential to improve the outcome of patients with breast cancer. Methods: Paclitaxel sensitivity was first evaluated using models of IFT20 deletion and overexpression of breast cancer cells in vitro and in vivo studies to identify the effect of IFT20 on paclitaxel chemoresistance. To delineate the molecular mechanism of IFT20 contributions to paclitaxel chemoresistance, changes in ASK signaling and its downstream JNK cascades expression were quantified using western blots, and the potential involvement of β-arrestin-1 was investigated using co-IP studies. Results: IFT20 is positively associated with shorter relapse-free survival in patients with system paclitaxel-based chemotherapy. High expressed IFT20 in breast cancer cells increases resistance to cell death upon paclitaxel treatment; in contrast, IFT20 knockdown enhances apoptosis in breast cancer cells in response to paclitaxel. Mechanistically, IFT20 triggers β-arrestin-1 to bind with ASK1 and promotes the ubiquitination of ASK1 degradation, leading to attenuating ASK1 signaling and its downstream JNK cascades, which helped cells to escape from cell death during paclitaxel treatment. Conclusion: IFT20 confers to paclitaxel chemoresistance. It interacts with β-arrestin-1 to mediate ubiquitination of ASK1 for feedback inhibition of ASK1/JNK signaling and restrains paclitaxel-induced apoptosis. These findings identify IFT20 as a promising novel target for overcoming paclitaxel resistance in breast cancer.


2021 ◽  
Vol 14 (673) ◽  
pp. eabc5763 ◽  
Author(s):  
Hema Kothari ◽  
Corey M. Williams ◽  
Chantel McSkimming ◽  
Fabrizio Drago ◽  
Melissa A. Marshall ◽  
...  

IL-1β is a key mediator of the cytokine storm linked to high morbidity and mortality from COVID-19, and IL-1β blockade with anakinra and canakinumab during COVID-19 infection has entered clinical trials. Using mass cytometry of human peripheral blood mononuclear cells, we identified effector memory CD4+ T cells and CD4−CD8low/−CD161+ T cells, specifically those positive for the chemokine receptor CCR6, as the circulating immune subtypes with the greatest response to IL-1β. This response manifested as increased phosphorylation and, thus, activation of the proinflammatory transcription factor NF-κB and was also seen in other subsets, including CD11c+ myeloid dendritic cells, classical monocytes, two subsets of natural killer cells (CD16−CD56brightCD161− and CD16−CD56dimCD161+), and lineage− (Lin−) cells expressing CD161 and CD25. IL-1β also induced a rapid but less robust increase in the phosphorylation of the kinase p38 as compared to that of NF-κB in most of these immune cell subsets. Prolonged IL-1β stimulation increased the phosphorylation of the transcription factor STAT3 and to a lesser extent that of STAT1 and STAT5 across various immune cell types. IL-1β–induced production of IL-6 likely led to the activation of STAT1 and STAT3 at later time points. Interindividual heterogeneity and inhibition of STAT activation by anakinra raise the possibility that assays measuring NF-κB phosphorylation in response to IL-1β in CCR6+ T cell subtypes could identify those patients at higher risk of cytokine storm and most likely to benefit from IL-1β–neutralizing therapies.


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