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Optimization of in vitro regeneration and Agrobacterium tumefaciens-mediated transformation with heat-resistant cDNA in Brassica oleracea subsp. italica cv. Green Marvel

Ravanfar SA, Aziz MA, Saud HM, Abdullah JO

Curr Genet, 2015 Nov;61(4):653-63.
PMID: 25986972 DOI: 10.1007/s00294-015-0494-x

An efficient system for shoot regeneration and Agrobacterium tumefaciens-mediated transformation of Brassica oleracea cv. Green Marvel cultivar is described. This study focuses on developing shoot regeneration from hypocotyl explants of broccoli cv. Green Marvel using thidiazuron (TDZ), zeatin, and kinetin, the optimization of factors affecting Agrobacterium-mediated transformation of the hypocotyl explants with heat-resistant cDNA, followed by the confirmation of transgenicity of the regenerants. High shoot regeneration was observed in 0.05-0.1 mg dm(-3) TDZ. TDZ at 0.1 mg dm(-3) produced among the highest percentage of shoot regeneration (96.67 %) and mean number of shoot formation (6.17). The highest percentage (13.33 %) and mean number (0.17) of putative transformant production were on hypocotyl explants subjected to preculture on shoot regeneration medium (SRM) with 200 µM acetosyringone. On optimization of bacterial density and inoculation time, the highest percentage and mean number of putative transformant production were on hypocotyl explants inoculated with a bacterial dilution of 1:5 for 30 min. Polymerase chain reaction (PCR) assay indicated a transformation efficiency of 8.33 %. The luciferase assay showed stable integration of the Arabidopsis thaliana HSP101 (AtHSP101) cDNA in the transgenic broccoli regenerants. Three out of five transgenic lines confirmed through PCR showed positive hybridization bands of the AtHSP101 cDNA through Southern blot analysis. The presence of AtHSP101 transcripts in the three transgenic broccoli lines indicated by reverse transcription-PCR (RT-PCR) confirmed the expression of the gene. In conclusion, an improved regeneration system has been established from hypocotyl explants of broccoli followed by successful transformation with AtHSP101 for resistance to high temperature.

Matched MeSH terms: Transcription Factors/metabolism
Fulltext Comparative analysis of cardiovascular development related genes in stem cells isolated from deciduous pulp and adipose tissue

Loo ZX, Kunasekaran W, Govindasamy V, Musa S, Abu Kasim NH

ScientificWorldJournal, 2014;2014:186508.
PMID: 25548778 DOI: 10.1155/2014/186508

Human exfoliated deciduous teeth (SHED) and adipose stem cells (ASC) were suggested as alternative cell choice for cardiac regeneration. However, the true functionability of these cells toward cardiac regeneration is yet to be discovered. Hence, this study was carried out to investigate the innate biological properties of these cell sources toward cardiac regeneration. Both cells exhibited indistinguishable MSCs characteristics. Human stem cell transcription factor arrays were used to screen expression levels in SHED and ASC. Upregulated expression of transcription factor (TF) genes was detected in both sources. An almost equal percentage of >2-fold changes were observed. These TF genes fall under several cardiovascular categories with higher expressions which were observed in growth and development of blood vessel, angiogenesis, and vasculogenesis categories. Further induction into cardiomyocyte revealed ASC to express more significantly cardiomyocyte specific markers compared to SHED during the differentiation course evidenced by morphology and gene expression profile. Despite this, spontaneous cellular beating was not detected in both cell lines. Taken together, our data suggest that despite being defined as MSCs, both ASC and SHED behave differently when they were cultured in a same cardiomyocytes culture condition. Hence, vigorous characterization is needed before introducing any cell for treating targeted diseases.

Matched MeSH terms: Transcription Factors/metabolism
Fulltext Targeting extracellular matrix remodeling in disease: Could resveratrol be a potential candidate?

Agarwal R, Agarwal P

Exp Biol Med (Maywood), 2017 Feb;242(4):374-383.
PMID: 27798117 DOI: 10.1177/1535370216675065

Disturbances of extracellular matrix homeostasis are associated with a number of pathological conditions. The ability of extracellular matrix to provide contextual information and hence control the individual or collective cellular behavior is increasingly being recognized. Hence, newer therapeutic approaches targeting extracellular matrix remodeling are widely investigated. We reviewed the current literature showing the effects of resveratrol on various aspects of extracellular matrix remodeling. This review presents a summary of the effects of resveratrol on extracellular matrix deposition and breakdown. Mechanisms of action of resveratrol in extracellular matrix deposition involving growth factors and their signaling pathways are discussed. Involvement of phosphoinositol-3-kinase/Akt and mitogen-activated protein kinase pathways and role of transcription factors and sirtuins on the effects of resveratrol on extracellular matrix homeostasis are summarized. It is evident from the literature presented in this review that resveratrol has significant effects on both the synthesis and breakdown of extracellular matrix. The major molecular targets of the action of resveratrol are growth factors and their signaling pathways, phosphoinositol-3-kinase/Akt and mitogen-activated protein kinase pathways, transcription factors, and SIRT-1. The effects of resveratrol on extracellular matrix and the molecular targets appear to be related to experimental models, experimental environment as well as the doses.

Matched MeSH terms: Transcription Factors/metabolism
Mature B-cell acute lymphoblastic leukaemia associated with a rare MLL-FOXO4 fusion gene

Lim L, Chen KS, Krishnan S, Gole L, Ariffin H

Br J Haematol, 2012 Jun;157(6):651.
PMID: 22429121 DOI: 10.1111/j.1365-2141.2012.09091.x
Matched MeSH terms: Transcription Factors/metabolism
Sheath blight of rice: a review and identification of priorities for future research

Singh P, Mazumdar P, Harikrishna JA, Babu S

Planta, 2019 Nov;250(5):1387-1407.
PMID: 31346804 DOI: 10.1007/s00425-019-03246-8

MAIN CONCLUSION: Rice sheath blight research should prioritise optimising biological control approaches, identification of resistance gene mechanisms and application in genetic improvement and smart farming for early disease detection. Rice sheath blight, caused by Rhizoctonia solani AG1-1A, is one of the most devasting diseases of the crop. To move forward with effective crop protection against sheath blight, it is important to review the published information related to pathogenicity and disease management and to determine areas of research that require deeper study. While progress has been made in the identification of pathogenesis-related genes both in rice and in the pathogen, the mechanisms remain unclear. Research related to disease management practices has addressed the use of agronomic practices, chemical control, biological control and genetic improvement: Optimising nitrogen fertiliser use in conjunction with plant spacing can reduce spread of infection while smart agriculture technologies such as crop monitoring with Unmanned Aerial Systems assist in early detection and management of sheath blight disease. Replacing older fungicides with natural fungicides and use of biological agents can provide effective sheath blight control, also minimising environmental impact. Genetic approaches that show promise for the control of sheath blight include treatment with exogenous dsRNA to silence pathogen gene expression, genome editing to develop rice lines with lower susceptibility to sheath blight and development of transgenic rice lines overexpressing or silencing pathogenesis related genes. The main challenges that were identified for effective crop protection against sheath blight are the adaptive flexibility of the pathogen, lack of resistant rice varieties, abscence of single resistance genes for use in breeding and low access of farmers to awareness programmes for optimal management practices.

Matched MeSH terms: Transcription Factors/metabolism
Reciprocal expression of the endocytic protein HIP1R and its repressor FOXP1 predicts outcome in R-CHOP-treated diffuse large B-cell lymphoma patients

Wong KK, Gascoyne DM, Brown PJ, Soilleux EJ, Snell C, Chen H, et al.

Leukemia, 2014 Feb;28(2):362-72.
PMID: 23884370 DOI: 10.1038/leu.2013.224

We previously identified autoantibodies to the endocytic-associated protein Huntingtin-interacting protein 1-related (HIP1R) in diffuse large B-cell lymphoma (DLBCL) patients. HIP1R regulates internalization of cell surface receptors via endocytosis, a process relevant to many therapeutic strategies including CD20 targeting with rituximab. In this study, we characterized HIP1R expression patterns, investigated a mechanism of transcriptional regulation and its clinical relevance in DLBCL patients treated with immunochemotherapy (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone, R-CHOP). HIP1R was preferentially expressed in germinal center B-cell-like DLBCL (P<0.0001) and inversely correlated with the activated B-cell-like DLBCL (ABC-DLBCL) associated transcription factor, Forkhead box P1 (FOXP1). HIP1R was confirmed as a direct FOXP1 target gene in ABC-DLBCL by FOXP1-targeted silencing and chromatin immunoprecipitation. Lower HIP1R protein expression (≤ 10% tumoral positivity) significantly correlated with inferior overall survival (OS, P=0.0003) and progression-free survival (PFS, P=0.0148) in R-CHOP-treated DLBCL patients (n=157). Reciprocal expression with ≥ 70% FOXP1 positivity defined FOXP1(hi)/HIP1R(lo) patients with particularly poor outcome (OS, P=0.0001; PFS, P=0.0016). In an independent R-CHOP-treated DLBCL (n=233) microarray data set, patients with transcript expression in lower quartile HIP1R and FOXP1(hi)/HIP1R(lo) subgroups exhibited worse OS, P=0.0044 and P=0.0004, respectively. HIP1R repression by FOXP1 is strongly associated with poor outcome, thus further understanding of FOXP1-HIP1R and/or endocytic signaling pathways might give rise to novel therapeutic options for DLBCL.

Matched MeSH terms: Forkhead Transcription Factors/metabolism
Fulltext FOXP2-positive diffuse large B-cell lymphomas exhibit a poor response to R-CHOP therapy and distinct biological signatures

Wong KK, Gascoyne DM, Soilleux EJ, Lyne L, Spearman H, Roncador G, et al.

Oncotarget, 2016 Aug 16;7(33):52940-52956.
PMID: 27224915 DOI: 10.18632/oncotarget.9507

FOXP2 shares partially overlapping normal tissue expression and functionality with FOXP1; an established diffuse large B-cell lymphoma (DLBCL) oncogene and marker of poor prognosis. FOXP2 is expressed in the plasma cell malignancy multiple myeloma but has not been studied in DLBCL, where a poor prognosis activated B-cell (ABC)-like subtype display partially blocked plasma cell differentiation. FOXP2 protein expression was detected in ABC-DLBCL cell lines, and in primary DLBCL samples tumoral FOXP2 protein expression was detected in both germinal center B-cell-like (GCB) and non-GCB DLBCL. In biopsies from DLBCL patients treated with immunochemotherapy (R-CHOP), ≥ 20% nuclear tumoral FOXP2-positivity (n = 24/158) correlated with significantly inferior overall survival (OS: P = 0.0017) and progression-free survival (PFS: P = 0.0096). This remained significant in multivariate analysis against either the international prognostic index score or the non-GCB DLBCL phenotype (P < 0.05 for both OS and PFS). Expression of BLIMP1, a marker of plasmacytic differentiation that is commonly inactivated in ABC-DLBCL, did not correlate with patient outcome or FOXP2 expression in this series. Increased frequency of FOXP2 expression significantly correlated with FOXP1-positivity (P = 0.0187), and FOXP1 co-immunoprecipitated FOXP2 from ABC-DLBCL cells indicating that these proteins can co-localize in a multi-protein complex. FOXP2-positive DLBCL had reduced expression of HIP1R (P = 0.0348), which is directly repressed by FOXP1, and exhibited distinct patterns of gene expression. Specifically in ABC-DLBCL these were associated with lower expression of immune response and T-cell receptor signaling pathways. Further studies are warranted to investigate the potential functional cooperativity between FOXP1 and FOXP2 in repressing immune responses during the pathogenesis of high-risk DLBCL.

Matched MeSH terms: Forkhead Transcription Factors/metabolism*
Fulltext Divergence of iron metabolism in wild Malaysian yeast

Lee HN, Mostovoy Y, Hsu TY, Chang AH, Brem RB

G3 (Bethesda), 2013 Dec 09;3(12):2187-94.
PMID: 24142925 DOI: 10.1534/g3.113.008011

Comparative genomic studies have reported widespread variation in levels of gene expression within and between species. Using these data to infer organism-level trait divergence has proven to be a key challenge in the field. We have used a wild Malaysian population of S. cerevisiae as a test bed in the search to predict and validate trait differences based on observations of regulatory variation. Malaysian yeast, when cultured in standard medium, activated regulatory programs that protect cells from the toxic effects of high iron. Malaysian yeast also showed a hyperactive regulatory response during culture in the presence of excess iron and had a unique growth defect in conditions of high iron. Molecular validation experiments pinpointed the iron metabolism factors AFT1, CCC1, and YAP5 as contributors to these molecular and cellular phenotypes; in genome-scale sequence analyses, a suite of iron toxicity response genes showed evidence for rapid protein evolution in Malaysian yeast. Our findings support a model in which iron metabolism has diverged in Malaysian yeast as a consequence of a change in selective pressure, with Malaysian alleles shifting the dynamic range of iron response to low-iron concentrations and weakening resistance to extreme iron toxicity. By dissecting the iron scarcity specialist behavior of Malaysian yeast, our work highlights the power of expression divergence as a signpost for biologically and evolutionarily relevant variation at the organismal level. Interpreting the phenotypic relevance of gene expression variation is one of the primary challenges of modern genomics.

Matched MeSH terms: Transcription Factors/metabolism; Basic-Leucine Zipper Transcription Factors/metabolism
Transcription factors NFIA and NFIB induce cellular differentiation in high-grade astrocytoma

Chen KS, Bridges CR, Lynton Z, Lim JWC, Stringer BW, Rajagopal R, et al.

J Neurooncol, 2020 Jan;146(1):41-53.
PMID: 31760595 DOI: 10.1007/s11060-019-03352-3

INTRODUCTION: Malignant astrocytomas are composed of heterogeneous cell populations. Compared to grade IV glioblastoma, low-grade astrocytomas have more differentiated cells and are associated with a better prognosis. Therefore, inducing cellular differentiation to alter the behaviour of high-grade astrocytomas may serve as a therapeutic strategy. The nuclear factor one (NFI) transcription factors are essential for normal astrocytic differentiation. Here, we investigate whether family members NFIA and NFIB act as effectors of cellular differentiation in glioblastoma.
METHODS: We analysed expression of NFIA and NFIB in mRNA expression data of high-grade astrocytoma and with immunofluorescence co-staining. Furthermore, we induced NFI expression in patient-derived subcutaneous glioblastoma xenografts via in vivo electroporation.
RESULTS: The expression of NFIA and NFIB is reduced in glioblastoma as compared to lower grade astrocytomas. At a cellular level, their expression is associated with differentiated and mature astrocyte-like tumour cells. In vivo analyses consistently demonstrate that expression of either NFIA or NFIB is sufficient to promote tumour cell differentiation in glioblastoma xenografts.
CONCLUSION: Our findings indicate that both NFIA and NFIB may have an endogenous pro-differentiative function in astrocytomas, similar to their role in normal astrocyte differentiation. Overall, our study establishes a basis for further investigation of targeting NFI-mediated differentiation as a potential differentiation therapy.

Matched MeSH terms: NFI Transcription Factors/metabolism*
Fulltext Cloning and characterization of short-chain N-acyl homoserine lactone-producing Enterobacter asburiae strain L1 from lettuce leaves

Lau YY, How KY, Yin WF, Chan KG

Microbiologyopen, 2018 Dec;7(6):e00610.
PMID: 29982994 DOI: 10.1002/mbo3.610

In gram-negative bacteria, bacterial communication or quorum sensing (QS) is achieved using common signaling molecules known as N-acyl homoserine lactones (AHL). We have previously reported the genome of AHL-producing bacterium, Enterobacter asburiae strain L1. In silico analysis of the strain L1 genome revealed the presence of a pair of luxI/R genes responsible for AHL-type QS, designated as easIR. In this work, the 639 bp luxI homolog, encoding 212 amino acids, have been cloned and overexpressed in Escherichia coli BL21 (DE3)pLysS. The purified protein (~25 kDa) shares high similarity to several members of the LuxI family among different E asburiae strains. Our findings showed that the heterologously expressed EasI protein has activated violacein production by AHL biosensor Chromobacterium violaceum CV026 as the wild-type E. asburiae. The mass spectrometry analysis showed the production of N-butanoyl homoserine lactone and N-hexanoyl homoserine lactone from induced E. coli harboring the recombinant EasI, suggesting that EasI is a functional AHL synthase. E. asburiae strain L1 was also shown to possess biofilm-forming characteristic activity using crystal violet binding assay. This is the first report on cloning and characterization of the luxI homolog from E. asburiae.

Matched MeSH terms: Transcription Factors/metabolism
Fulltext Pbx1 is essential for growth of zebrafish swim bladder

Teoh PH, Shu-Chien AC, Chan WK

Dev. Dyn., 2010 Mar;239(3):865-74.
PMID: 20108353 DOI: 10.1002/dvdy.22221

pbx1, a TALE (three-amino acid loop extension) homeodomain transcription factor, is involved in a diverse range of developmental processes. We examined the expression of pbx1 during zebrafish development by in situ hybridization. pbx1 transcripts could be detected in the central nervous system and pharyngeal arches from 24 hpf onwards. In the swim bladder anlage, pbx1 was detected as early as 28 hpf, making it the earliest known marker for this organ. Morpholino-mediated gene knockdown of pbx1 revealed that the swim bladder failed to inflate, with eventual lethality occurring by 8 dpf. The knockdown of pbx1 did not perturb the expression of prdc and foxA3, with both early swim bladder markers appearing normally at 36 and 48 hpf, respectively. However, the expression of anxa5 was completely abolished by pbx1 knockdown at 60 hpf suggesting that pbx1 may be required during the late stage of swim bladder development.

Matched MeSH terms: Transcription Factors/metabolism*
Lauric acid alleviates insulin resistance by improving mitochondrial biogenesis in THP-1 macrophages

Tham YY, Choo QC, Muhammad TST, Chew CH

Mol Biol Rep, 2020 Dec;47(12):9595-9607.
PMID: 33259010 DOI: 10.1007/s11033-020-06019-9

Mitochondrial dysfunction plays a crucial role in the central pathogenesis of insulin resistance and type 2 diabetes mellitus. Macrophages play important roles in the pathogenesis of insulin resistance. Lauric acid is a 12-carbon medium chain fatty acid (MCFA) found abundantly in coconut oil or palm kernel oil and it comes with multiple beneficial effects. This research objective was to uncover the effects of the lauric acid on glucose uptake, mitochondrial function and mitochondrial biogenesis in insulin-resistant macrophages. THP-1 monocytes were differentiated into macrophages and induce insulin resistance, before they were treated with increasing doses of lauric acid (5 μM, 10 μM, 20 μM, and 50 μM). Glucose uptake assay, cellular ROS and ATP production assays, mitochondrial content and membrane potential assay were carried out to analyse the effects of lauric acid on insulin resistance and mitochondrial biogenesis in the macrophages. Quantitative RT-PCR (qRT-PCR) and western blot analysis were also performed to determine the expression of the key regulators. Insulin-resistant macrophages showed lower glucose uptake, GLUT-1 and GLUT-3 expression, and increased hallmarks of mitochondrial dysfunction. Interestingly, lauric acid treatment upregulated glucose uptake, GLUT-1 and GLUT-3 expressions. The treatment also restored the mitochondrial biogenesis in the insulin-resistant macrophages by improving ATP production, oxygen consumption, mitochondrial content and potential, while it promoted the expression of mitochondrial biogenesis regulator genes such as TFAM, PGC-1α and PPAR-γ. We show here that lauric acid has the potential to improve insulin sensitivity and mitochondrial dysregulation in insulin-resistant macrophages.

Matched MeSH terms: Transcription Factors/metabolism
The transcript level of interleukin-6 in the cartilage of idiopathic osteoarthritis of knee

Moktar NM, Yusof HM, Yahaya NH, Muhamad R, Das S

Clin Ter, 2010;161(1):25-8.
PMID: 20393674

AIMS: The mRNA level for interleukin-6 (IL-6) is an important marker of osteoarthritis (OA). The present study aimed to investigate the level of IL-6 mRNA in the cartilage of OA knee while comparing it to the normal cartilage obtained from the same patient.
MATERIALS AND METHODS: A total of 21 patients who underwent total knee replacement were recruited for this study. Sectioning of the destructive cartilage was performed in the medial part of the proximal tibiofemoral cartilage. The unaffected lateral part of the knee in the same patient, served as a control. The mRNA level for IL-6 was assessed using LightCycler 2.0 quantitative real-time polymerase chain reaction (qRT-PCR). actin mRNA was used as an endogenous control.
RESULTS: Twelve out of 21 patients (57.1%) exhibited up regulation of IL-6 mRNA in the OA cartilage as compared to the normal cartilage. The rest of the patients (42.9%) showed down regulation of IL-6 mRNA. The statistical analysis showed there was insignificant level of IL-6 mRNA in the OA (1.91 +/- 0.45) as compared to the normal cartilage (1.13 +/- 0.44) (p > 0.05). The inter-individual variation in the level of IL-6 mRNA in the cartilage of idiopathic knee was in accordance with previous findings.
CONCLUSIONS: These observations suggest IL-6 could also act as a catabolic agent in some patients or its expression might be influenced by other cytokines.
Study site: Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM), Kuala Lumpur, Malaysia

Matched MeSH terms: Transcription Factors/metabolism
An overview of signaling pathways regulating YAP/TAZ activity

Heng BC, Zhang X, Aubel D, Bai Y, Li X, Wei Y, et al.

Cell Mol Life Sci, 2021 Jan;78(2):497-512.
PMID: 32748155 DOI: 10.1007/s00018-020-03579-8

YAP and TAZ are ubiquitously expressed homologous proteins originally identified as penultimate effectors of the Hippo signaling pathway, which plays a key role in maintaining mammalian tissue/organ size. Presently, it is known that YAP/TAZ also interact with various non-Hippo signaling pathways, and have diverse roles in multiple biological processes, including cell proliferation, tissue regeneration, cell lineage fate determination, tumorigenesis, and mechanosensing. In this review, we first examine the various microenvironmental cues and signaling pathways that regulate YAP/TAZ activation, through the Hippo and non-Hippo signaling pathways. This is followed by a brief summary of the interactions of YAP/TAZ with TEAD1-4 and a diverse array of other non-TEAD transcription factors. Finally, we offer a critical perspective on how increasing knowledge of the regulatory mechanisms of YAP/TAZ signaling might open the door to novel therapeutic applications in the interrelated fields of biomaterials, tissue engineering, regenerative medicine and synthetic biology.

Matched MeSH terms: Transcription Factors/metabolism*
Application of Ti3 C2 MXene Quantum Dots for Immunomodulation and Regenerative Medicine

Rafieerad A, Yan W, Sequiera GL, Sareen N, Abu-El-Rub E, Moudgil M, et al.

Adv Healthc Mater, 2019 08;8(16):e1900569.
PMID: 31265217 DOI: 10.1002/adhm.201900569

Inflammation is tightly linked to tissue injury. In regenerative medicine, immune activation plays a key role in rejection of transplanted stem cells and reduces the efficacy of stem cell therapies. Next-generation smart biomaterials are reported to possess multiple biologic properties for tissue repair. Here, the first use of 0D titanium carbide (Ti3 C2 ) MXene quantum dots (MQDs) for immunomodulation is presented with the goal of enhancing material-based tissue repair after injury. MQDs possess intrinsic immunomodulatory properties and selectively reduce activation of human CD4+ IFN-γ+ T-lymphocytes (control 87.1 ± 2.0%, MQDs 68.3 ± 5.4%) while promoting expansion of immunosuppressive CD4+ CD25+ FoxP3+ regulatory T-cells (control 5.5 ± 0.7%, MQDs 8.5 ± 0.8%) in a stimulated lymphocyte population. Furthermore, MQDs are biocompatible with bone marrow-derived mesenchymal stem cells and induced pluripotent stem cell-derived fibroblasts. Finally, Ti3 C2 MQDs are incorporated into a chitosan-based hydrogel to create a 3D platform with enhanced physicochemical properties for stem cell delivery and tissue repair. This composite hydrogel demonstrates increased conductivity while maintaining injectability and thermosensitivity. These findings suggest that this new class of biomaterials may help bridge the translational gap in material and stem cell-based therapies for tissue repair and treatment of inflammatory and degenerative diseases.

Matched MeSH terms: Forkhead Transcription Factors/metabolism
Fulltext PIP4Ks impact on PI3K, FOXP3, and UHRF1 signaling and modulate human regulatory T cell proliferation and immunosuppressive activity

Poli A, Abdul-Hamid S, Zaurito AE, Campagnoli F, Bevilacqua V, Sheth B, et al.

Proc Natl Acad Sci U S A, 2021 08 03;118(31).
PMID: 34312224 DOI: 10.1073/pnas.2010053118

Regulatory T cells (Tregs) play fundamental roles in maintaining peripheral tolerance to prevent autoimmunity and limit legitimate immune responses, a feature hijacked in tumor microenvironments in which the recruitment of Tregs often extinguishes immune surveillance through suppression of T-effector cell signaling and tumor cell killing. The pharmacological tuning of Treg activity without impacting on T conventional (Tconv) cell activity would likely be beneficial in the treatment of various human pathologies. PIP4K2A, 2B, and 2C constitute a family of lipid kinases that phosphorylate PtdIns5P to PtdIns(4,5)P 2 They are involved in stress signaling, act as synthetic lethal targets in p53-null tumors, and in mice, the loss of PIP4K2C leads to late onset hyperinflammation. Accordingly, a human single nucleotide polymorphism (SNP) near the PIP4K2C gene is linked with susceptibility to autoimmune diseases. How PIP4Ks impact on human T cell signaling is not known. Using ex vivo human primary T cells, we found that PIP4K activity is required for Treg cell signaling and immunosuppressive activity. Genetic and pharmacological inhibition of PIP4K in Tregs reduces signaling through the PI3K, mTORC1/S6, and MAPK pathways, impairs cell proliferation, and increases activation-induced cell death while sparing Tconv. PIP4K and PI3K signaling regulate the expression of the Treg master transcriptional activator FOXP3 and the epigenetic signaling protein Ubiquitin-like containing PHD and RING finger domains 1 (UHRF1). Our studies suggest that the pharmacological inhibition of PIP4K can reprogram human Treg identity while leaving Tconv cell signaling and T-helper differentiation to largely intact potentially enhancing overall immunological activity.

Matched MeSH terms: Forkhead Transcription Factors/metabolism*
Fulltext Peroxisome proliferator-activated receptor gamma: promising target in glioblastoma

Gupta G, Singhvi G, Chellappan DK, Sharma S, Mishra A, Dahiya R, et al.

Panminerva Med, 2018 Sep;60(3):109-116.
PMID: 30176701 DOI: 10.23736/S0031-0808.18.03462-6

Glioblastoma, also known as glioblastoma multiforme, is the most common and worldwide-spread cancer that begins within the brain. Glioblastomas represent 15% of brain tumors. The most common length of survival following diagnosis is 12 to 14 months with less than 3% to 5% of people surviving longer than five years. Without treatment, survival is typically 3 months. Among all receptors, special attention has been focused on the role of peroxisome proliferator-activated receptors (PPARs) in glioblastoma. PPARs are ligand-activated intracellular transcription factors. The PPAR subfamily consists of three subtypes encoded by distinct genes named PPARα, PPARβ/δ, and PPARγ. PPARγ is the most extensively studied subtype of PPAR. There has been interesting preliminary evidence suggesting that diabetic patients receiving PPARγ agonists, a group of anti-diabetics, thiazolidinedione drugs, have an increased median survival for glioblastoma. In this paper, the recent progresses in understanding the potential mechanism of PPARγ in glioblastoma are summarized.

Matched MeSH terms: Transcription Factors/metabolism
Fulltext Association analysis identifies 65 new breast cancer risk loci

Michailidou K, Lindström S, Dennis J, Beesley J, Hui S, Kar S, et al.

Nature, 2017 Nov 02;551(7678):92-94.
PMID: 29059683 DOI: 10.1038/nature24284

Breast cancer risk is influenced by rare coding variants in susceptibility genes, such as BRCA1, and many common, mostly non-coding variants. However, much of the genetic contribution to breast cancer risk remains unknown. Here we report the results of a genome-wide association study of breast cancer in 122,977 cases and 105,974 controls of European ancestry and 14,068 cases and 13,104 controls of East Asian ancestry. We identified 65 new loci that are associated with overall breast cancer risk at P

Matched MeSH terms: Transcription Factors/metabolism
Fulltext Variations in DREB1A and VP1.1 Genes Show Association with Salt Tolerance Traits in Wild Tomato (Solanum pimpinellifolium)

Rao ES, Kadirvel P, Symonds RC, Geethanjali S, Thontadarya RN, Ebert AW

PLoS One, 2015;10(7):e0132535.
PMID: 26161546 DOI: 10.1371/journal.pone.0132535

Association analysis was conducted in a core collection of 94 genotypes of Solanum pimpinellifolium to identify variations linked to salt tolerance traits (physiological and yield traits under salt stress) in four candidate genes viz., DREB1A, VP1.1, NHX1, and TIP. The candidate gene analysis covered a concatenated length of 4594 bp per individual and identified five SNP/Indels in DREB1A and VP1.1 genes explaining 17.0% to 25.8% phenotypic variation for various salt tolerance traits. Out of these five alleles, one at 297 bp in DREB1A had in-frame deletion of 6 bp (CTGCAT) or 12 bp (CTGCATCTGCAT), resulting in two alleles, viz., SpDREB1A_297_6 and SpDREB1A_297_12. These alleles individually or as haplotypes accounted for maximum phenotypic variance of about 25% for various salt tolerance traits. Design of markers for selection of the favorable alleles/haplotypes will hasten marker-assisted introgression of salt tolerance from S. pimpinellifolium into cultivated tomato.

Matched MeSH terms: Transcription Factors/metabolism
Fulltext Mutated HRAS Activates YAP1-AXL Signaling to Drive Metastasis of Head and Neck Cancer

Jagadeeshan S, Prasad M, Badarni M, Ben-Lulu T, Liju VB, Mathukkada S, et al.

Cancer Res, 2023 Apr 04;83(7):1031-1047.
PMID: 36753744 DOI: 10.1158/0008-5472.CAN-22-2586

The survival rate for patients with head and neck cancer (HNC) diagnosed with cervical lymph node (cLN) or distant metastasis is low. Genomic alterations in the HRAS oncogene are associated with advanced tumor stage and metastasis in HNC. Elucidation of the molecular mechanisms by which mutated HRAS (HRASmut) facilitates HNC metastasis could lead to improved treatment options for patients. Here, we examined metastasis driven by mutant HRAS in vitro and in vivo using HRASmut human HNC cell lines, patient-derived xenografts, and a novel HRASmut syngeneic model. Genetic and pharmacological manipulations indicated that HRASmut was sufficient to drive invasion in vitro and metastasis in vivo. Targeted proteomic analysis showed that HRASmut promoted AXL expression via suppressing the Hippo pathway and stabilizing YAP1 activity. Pharmacological blockade of HRAS signaling with the farnesyltransferase inhibitor tipifarnib activated the Hippo pathway and reduced the nuclear export of YAP1, thus suppressing YAP1-mediated AXL expression and metastasis. AXL was required for HRASmut cells to migrate and invade in vitro and to form regional cLN and lung metastases in vivo. In addition, AXL-depleted HRASmut tumors displayed reduced lymphatic and vascular angiogenesis in the primary tumor. Tipifarnib treatment also regulated AXL expression and attenuated VEGFA and VEGFC expression, thus regulating tumor-induced vascular formation and metastasis. Our results indicate that YAP1 and AXL are crucial factors for HRASmut-induced metastasis and that tipifarnib treatment can limit the metastasis of HNC tumors with HRAS mutations by enhancing YAP1 cytoplasmic sequestration and downregulating AXL expression.
SIGNIFICANCE: Mutant HRAS drives metastasis of head and neck cancer by switching off the Hippo pathway to activate the YAP1-AXL axis and to stimulate lymphovascular angiogenesis.

Matched MeSH terms: Transcription Factors/metabolism

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