PD-L1 lncRNA splice isoform promotes lung adenocarcinoma progression via enhancing c-Myc activity
Qu, S;Jiao, Z;Lu, G;Yao, B;Wang, T;Rong, W;Xu, J;Fan, T;Sun, X;Yang, R;Wang, J;Yao, Y;Xu, G;Yan, X;Wang, T;Liang, H;Zen, K;
PMID: 33849634 | DOI: 10.1186/s13059-021-02331-0
Although using a blockade of programmed death-ligand 1 (PD-L1) to enhance T cell immune responses shows great promise in tumor immunotherapy, the immune-checkpoint inhibition strategy is limited for patients with solid tumors. The mechanism and efficacy of such immune-checkpoint inhibition strategies in solid tumors remains unclear. Employing qRT-PCR, Sanger sequencing, and RNA BaseScope analysis, we show that human lung adenocarcinoma (LUAD) all produce a long non-coding RNA isoform of PD-L1 (PD-L1-lnc) by alternative splicing, regardless if the tumor is positive or negative for the protein PD-L1. Similar to PD-L1 mRNA, PD-L1-lnc in various lung adenocarcinoma cells is significantly upregulated by IFNγ. Both in vitro and in vivo studies demonstrate that PD-L1-lnc increases proliferation and invasion but decreases apoptosis of lung adenocarcinoma cells. Mechanistically, PD-L1-lnc promotes lung adenocarcinoma progression through directly binding to c-Myc and enhancing c-Myc transcriptional activity. In summary, the PD-L1 gene can generate a long non-coding RNA through alternative splicing to promote lung adenocarcinoma progression by enhancing c-Myc activity. Our results argue in favor of investigating PD-L1-lnc depletion in combination with PD-L1 blockade in lung cancer therapy.
Acta neuropathologica communications
Davis, SE;Cook, AK;Hall, JA;Voskobiynyk, Y;Carullo, NV;Boyle, NR;Hakim, AR;Anderson, KM;Hobdy, KP;Pugh, DA;Murchison, CF;McMeekin, LJ;Simmons, M;Margolies, KA;Cowell, RM;Nana, AL;Spina, S;Grinberg, LT;Miller, BL;Seeley, WW;Arrant, AE;
PMID: 37118844 | DOI: 10.1186/s40478-023-01571-4
Loss of function progranulin (GRN) mutations are a major autosomal dominant cause of frontotemporal dementia (FTD). Patients with FTD due to GRN mutations (FTD-GRN) develop frontotemporal lobar degeneration with TDP-43 pathology type A (FTLD-TDP type A) and exhibit elevated levels of lysosomal proteins and storage material in frontal cortex, perhaps indicating lysosomal dysfunction as a mechanism of disease. To investigate whether patients with sporadic FTLD exhibit similar signs of lysosomal dysfunction, we compared lysosomal protein levels, transcript levels, and storage material in patients with FTD-GRN or sporadic FTLD-TDP type A. We analyzed samples from frontal cortex, a degenerated brain region, and occipital cortex, a relatively spared brain region. In frontal cortex, patients with sporadic FTLD-TDP type A exhibited similar increases in lysosomal protein levels, transcript levels, and storage material as patients with FTD-GRN. In occipital cortex of both patient groups, most lysosomal measures did not differ from controls. Frontal cortex from a transgenic mouse model of TDP-opathy had similar increases in cathepsin D and lysosomal storage material, showing that TDP-opathy and neurodegeneration can drive these changes independently of progranulin. To investigate these changes in additional FTLD subtypes, we analyzed frontal cortical samples from patients with sporadic FTLD-TDP type C or Pick's disease, an FTLD-tau subtype. All sporadic FTLD groups had similar increases in cathepsin D activity, lysosomal membrane proteins, and storage material as FTD-GRN patients. However, patients with FTLD-TDP type C or Pick's disease did not have similar increases in lysosomal transcripts as patients with FTD-GRN or sporadic FTLD-TDP type A. Based on these data, accumulation of lysosomal proteins and storage material may be a common aspect of end-stage FTLD. However, the unique changes in gene expression in patients with FTD-GRN or sporadic FTLD-TDP type A may indicate distinct underlying lysosomal changes among FTLD subtypes.
Ziminski J, Hessler S, Margetts-Smith G, Sieburg MC, Crombag HS, Koya E.
PMID: 28213443 | DOI: 10.1523/JNEUROSCI.3766-16.2017
Cues that predict the availability of food rewards influence motivational states and elicit food-seeking behaviors. If a cue no longer predicts food availability, animals may adapt accordingly by inhibiting food seeking responses. Sparsely activated sets of neurons, coined neuronal ensembles, have been shown to encode the strength of reward-cue associations. While alterations in intrinsic excitability have been shown to underlie many learning and memory processes, little is known about these properties specifically on cue-activated neuronal ensembles. We examined the activation patterns of cue-activated orbitofrontal cortex (OFC) and nucleus accumbens (NAc) shell ensembles using wild-type and Fos-GFP mice following appetitive conditioning with sucrose and extinction learning. We also investigated the neuronal excitability of recently activated, GFP+ neurons in these brain areas using whole-cell electrophysiology in brain slices. Exposure to a sucrose cue elicited activation of neurons in both the NAc shell and OFC. In the NAc shell, but not the OFC, these activated GFP+ neurons were more excitable than surrounding GFP- neurons. Following extinction, the number of neurons activated in both areas was reduced and activated ensembles in neither area exhibited altered excitability. These data suggest that learning-induced alterations in the intrinsic excitability of neuronal ensembles is regulated dynamically across different brain areas. Furthermore, we show that changes in associative strength modulate the excitability profile of activated ensembles in the NAc shell.SIGNIFICANCE STATEMENTSparsely distributed sets of neurons called 'neuronal ensembles' encode learned associations about food and cues predictive of its availability. Widespread changes in neuronal excitability have been observed in limbic brain areas after associative learning, but little is known about the excitability changes that occur specifically on neuronal ensembles that encode appetitive associations. Here we reveal that sucrose cue exposure recruited a more excitable ensemble in the nucleus accumbens, but not orbitofrontal cortex compared to their surrounding neurons. This excitability difference was not observed when the cue's salience was diminished following extinction learning. These novel data provide evidence that the intrinsic excitability of appetitive memory-encoding ensembles is differentially regulated across brain areas and dynamically adapts to changes in associative strength.
Englund, J;Haikonen, J;Shteinikov, V;Amarilla, SP;Atanasova, T;Shintyapina, A;Ryazantseva, M;Partanen, J;Voikar, V;Lauri, SE;
PMID: 34663781 | DOI: 10.1038/s41398-021-01654-7
Early life stress (ELS) is a well-characterized risk factor for mood and anxiety disorders. GABAergic microcircuits in the amygdala are critically implicated in anxiety; however, whether their function is altered after ELS is not known. Here we identify a novel mechanism by which kainate receptors (KARs) modulate feedforward inhibition in the lateral amygdala (LA) and show that this mechanism is downregulated after ELS induced by maternal separation (MS). Specifically, we show that in control rats but not after MS, endogenous activity of GluK1 subunit containing KARs disinhibit LA principal neurons during activation of cortical afferents. GluK1 antagonism attenuated excitability of parvalbumin (PV)-expressing interneurons, resulting in loss of PV-dependent inhibitory control and an increase in firing of somatostatin-expressing interneurons. Inactivation of Grik1 expression locally in the adult amygdala reduced ongoing GABAergic transmission and was sufficient to produce a mild anxiety-like behavioral phenotype. Interestingly, MS and GluK1-dependent phenotypes showed similar gender specificity, being detectable in male but not female rodents. Our data identify a novel KAR-dependent mechanism for cell-type and projection-specific functional modulation of the LA GABAergic microcircuit and suggest that the loss of GluK1 KAR function contributes to anxiogenesis after ELS.
Shin S, Pribiag H, Lilascharoen V, Knowland D, Wang XY, Lim BK.
PMID: 29276054 | DOI: 10.1016/j.neuron.2017.11.040
Early life stress (ELS) in the form of child abuse/neglect is associated with an increased risk of developing social dysfunction in adulthood. Little is known, however, about the neural substrates or the neuromodulatory signaling that govern ELS-induced social dysfunction. Here, we show that ELS-induced downregulation of dopamine receptor 3 (Drd3) signaling and its corresponding effects on neural activity in the lateral septum (LS) are both necessary and sufficient to cause social abnormalities in adulthood. Using in vivo Ca2+ imaging, we found that Drd3-expressing-LS (Drd3LS) neurons in animals exposed to ELS show blunted activity in response to social stimuli. In addition, optogenetic activation of Drd3LS neurons rescues ELS-induced social impairments. Furthermore, pharmacological treatment with a Drd3 agonist, which increases Drd3LS neuronal activity, normalizes the social dysfunctions of ELS mice. Thus, we identify Drd3 in the LS as a critical mediator and potential therapeutic target for the social abnormalities caused by ELS.
Front Cell Neurosci. 2018 Oct 9;12:341.
Yoo T, Cho H, Lee J, Park H, Yoo YE, Yang E, Kim JY, Kim H, Kim E.
PMID: 30356810 | DOI: 10.3389/fncel.2018.00341
Shank3 is an excitatory postsynaptic scaffolding protein implicated in multiple brain disorders, including autism spectrum disorders (ASD) and Phelan-McDermid syndrome (PMS). Although previous neurobiological studies on Shank3 and Shank3-mutant mice have revealed diverse roles of Shank3 in the regulation of synaptic, neuronal and brain functions, whether Shank3 expression in specific cell types distinctly contributes to mouse phenotypes remains largely unclear. In the present study, we generated two Shank3-mutant mouse lines (exons 14-16) carrying global and GABA neuron-specific deletions and characterized their electrophysiological and behavioral phenotypes. These mouse lines show similar decreases in excitatory synaptic input onto dorsolateral striatal neurons. In addition, the abnormal social and locomotor behaviors observed in global Shank3-mutant mice are strongly mimicked by GABA neuron-specific Shank3-mutant mice, whereas the repetitive and anxiety-like behaviors are only partially mimicked. These results suggest that GABAergic Shank3 (exons 14-16) deletion has strong influences on striatal excitatory synaptic transmission and social and locomotor behaviors in mice.
Xue T, Wang WG, Zhou XY, Li XQ.
PMID: - | DOI: 10.1016/j.pathol.2018.08.011
Summary Programmed cell death ligand 1 (PD-L1) is upregulated in various types of haematological malignancies and is associated with immunosuppression. This study aimed to investigate the expression pattern of PD-L1 in Epstein–Barr virus (EBV)-positive diffuse large B-cell lymphoma (DLBCL). We retrospectively analysed clinicopathological characteristics in 30 cases of EBV-positive DLBCL and immunohistochemically evaluated the level of membrane bound PD-L1 protein. Twenty-eight cases expressed PD-L1 protein 15 of which showed an intense positive staining. In addition, we investigated the relationships between PD-L1 protein and PD-L1 mRNA and MYC, respectively. The expression level of PD-L1 protein was not fully parallel with PD-L1 mRNA, and no significant correlation was observed between PD-L1 protein and MYC. Notably, PD-L1 mRNA was at a low dosage, which indicated that there might be other mechanisms inducing the overexpression of membrane bound PD-L1 protein apart from genetic alterations. Furthermore, the low expression level of MYC may not interfere with the PD-L1 protein expression in EBV-positive DLBCL. In conclusion, overexpression of PD-L1 protein can be observed in EBV-positive DLBCL, and the level was non-parallel with both PD-L1 mRNA and MYC. Moreover, we emphasise that immunohistochemistry is a clinically reasonable method for screening formalin fixed, paraffin embedded (FFPE) tumour samples in this entity.
Cutando, L;Puighermanal, E;Castell, L;Tarot, P;Belle, M;Bertaso, F;Arango-Lievano, M;Ango, F;Rubinstein, M;Quintana, A;Chédotal, A;Mameli, M;Valjent, E;
PMID: 35710984 | DOI: 10.1038/s41593-022-01092-8
The cerebellum, a primary brain structure involved in the control of sensorimotor tasks, also contributes to higher cognitive functions including reward, emotion and social interaction. Although the regulation of these behaviors has been largely ascribed to the monoaminergic system in limbic regions, the contribution of cerebellar dopamine signaling in the modulation of these functions remains largely unknown. By combining cell-type-specific transcriptomics, histological analyses, three-dimensional imaging and patch-clamp recordings, we demonstrate that cerebellar dopamine D2 receptors (D2Rs) in mice are preferentially expressed in Purkinje cells (PCs) and regulate synaptic efficacy onto PCs. Moreover, we found that changes in D2R levels in PCs of male mice during adulthood alter sociability and preference for social novelty without affecting motor functions. Altogether, these findings demonstrate novel roles for D2R in PC function and causally link cerebellar D2R levels of expression to social behaviors.
Guo L, Li W, Zhu X, Ling Y, Qiu T, Dong L, Fang Y, Yang H, Ying J.
PMID: 27390646 | DOI: 10.1186/s40064-016-2513-x
Abstract
PURPOSE:
To estimate the therapeutic potential of PD-L1 inhibition in breast cancer, we evaluated the prevalence and significance of PD-L1 protein expression with a validated antibody and CD274 gene alternation in a large cohort of triple negative breast cancer (TNBC) and correlated with clinicopathological data and patients overall survival.
METHODS:
Immunohistochemistry and in situ mRNA hybridization was used to detect PD-L1 protein and mRNA expression in tumor tissues from 183 TNBC patients respectively. Fluorescence in situ hybridization analysis was performed on PD-L1 strong expression samples to assess copy number on chromosome 9p24.1 of CD274 gene.
RESULTS:
Expression of PD-L1 by immune cells was observed in 4.9 % of TNBC, while expression by tumor cells accounted for 8.7 %. There was a high concordance in PD-L1 protein expression and PDL1 mRNA expression. Samples with PD-L1 strong expression were found to have a CD274 gene copy number gain. PD-L1 expression was correlated with higher tumor grade, but was independent of menopausal status, lymph nodes metastasis, histological subtype and tumor size. In addition, we used precise stratification of PD-L1 expression on tumor or immune cells of certain breast cancer subtype and suggested that patients with PD-L1 expression in basal-like tumors by immune cells or with CD274 gene copy number gain had a longer disease-specific overall survival.
CONCLUSIONS:
Our findings may promote the more precise analysis of PD-L1 expression in breast cancer and aid the selection of patients who may benefit from immune therapy.
Licenziato, L;Minoli, L;Ala, U;Marconato, L;Fanelli, A;Giannuzzi, D;De Maria, R;Iussich, S;Orlando, G;Bertoni, F;Aresu, L;
PMID: 36951124 | DOI: 10.1177/03009858231162209
Canine diffuse large B-cell lymphoma (cDLBCL) is characterized by high mortality and clinical heterogeneity. Although chemo-immunotherapy improves outcome, treatment response remains mainly unpredictable. To identify a set of immune-related genes aberrantly regulated and impacting the prognosis, we explored the immune landscape of cDLBCL by NanoString. The immune gene expression profile of 48 fully clinically characterized cDLBCLs treated with chemo-immunotherapy was analyzed with the NanoString nCounter Canine IO Panel using RNA extracted from tumor tissue paraffin blocks. A Cox proportional-hazards model was used to design a prognostic gene signature. The Cox model identified a 6-gene signature (IL2RB, BCL6, TXK, C2, CDKN2B, ITK) strongly associated with lymphoma-specific survival, from which a risk score was calculated. Dogs were assigned to high-risk or low-risk groups according to the median score. Thirty-nine genes were differentially expressed between the 2 groups. Gene set analysis highlighted an upregulation of genes involved in complement activation, cytotoxicity, and antigen processing in low-risk dogs compared with high-risk dogs, whereas genes associated with cell cycle were downregulated in dogs with a lower risk. In line with these results, cell type profiling suggested the abundance of natural killer and CD8+ cells in low-risk dogs compared with high-risk dogs. Furthermore, the prognostic power of the risk score was validated in an independent cohort of cDLBCL. In conclusion, the 6-gene-derived risk score represents a robust biomarker in predicting the prognosis in cDLBCL. Moreover, our results suggest that enhanced tumor antigen recognition and cytotoxic activity are crucial in achieving a more effective response to chemo-immunotherapy.
Filley A, Henriquez M, Bhowmik T, Tewari BN, Rao X, Wan J, Miller MA, Liu Y, Bentley RT, Dey M.
PMID: 29330750 | DOI: 10.1007/s11060-018-2753-4
Malignant glioma (MG), the most common primary brain tumor in adults, is extremely aggressive and uniformly fatal. Several treatment strategies have shown significant preclinical promise in murine models of glioma; however, none have produced meaningful clinicalresponses in human patients. We hypothesize that introduction of an additional preclinical animal model better approximating the complexity of human MG, particularly in interactions with host immune responses, will bridge the existing gap between these two stages of testing. Here, we characterize the immunologic landscape and gene expression profiles of spontaneous canine glioma and evaluate its potential for serving as such a translational model. RNA in situ hybridization, flowcytometry, and RNA sequencing were used to evaluate immune cell presence and gene expression in healthy and glioma-bearing canines. Similar to human MGs, canine gliomas demonstrated increased intratumoral immune cell infiltration (CD4+, CD8+ and CD4+Foxp3+ T cells). The peripheral blood of glioma-bearing dogs also contained a relatively greater proportion of CD4+Foxp3+ regulatory T cells and plasmacytoid dendritic cells. Tumors were strongly positive for PD-L1 expression and glioma-bearing animals also possessed a greater proportion of immune cells expressing the immune checkpoint receptors CTLA-4 and PD-1. Analysis of differentially expressed genes in our canine populations revealed several genetic changes paralleling those known to occur in human disease. Naturally occurring canine glioma has many characteristics closely resembling human disease, particularly with respect to genetic dysregulation and host immune responses to tumors, supporting its use as a translational model in the preclinical testing of prospective anti-glioma therapies proven successful in murine studies.
Newton, D;Oh, H;Shukla, R;Misquitta, K;Fee, C;Banasr, M;Sibille, E;
| DOI: 10.1016/j.biopsych.2021.10.015
Introduction Information processing in cortical cell microcircuits involves regulation of excitatory pyramidal (PYR) cells by inhibitory Somatostatin- (SST), Parvalbumin- (PV), and Vasoactive intestinal peptide- (VIP) expressing interneurons. Human post-mortem and rodent studies show impaired PYR-cell dendritic morphology and decreased SST-cell markers in MDD or after chronic stress. However, knowledge of coordinated changes across microcircuit cell-types is virtually absent. Methods We investigated the transcriptomic effects of unpredictable chronic mild stress (UCMS) on distinct microcircuit cell-types in the medial prefrontal cortex (Cingulate regions 24a/b and 32) in mice. C57Bl/6 mice, exposed to UCMS or control housing for five weeks, were assessed for anxiety- and depressive-like behaviors. Microcircuit cell-types were laser-microdissected and processed for RNA-sequencing. Results UCMS induced predicted elevations in behavioral emotionality in mice. DESeq2 analysis revealed unique differentially-expressed genes in each cell-type after UCMS. Pre-synaptic functions, oxidative stress response, metabolism, and translational regulation were differentially dysregulated across cell-types, whereas nearly all cell-types showed downregulated post-synaptic gene signatures. Across the cortical microcircuit, we observed a shift from a distributed transcriptomic coordination across cell-types in controls towards UCMS-induced increased coordination between PYR-, SST- and PV-cells, and hub-like role for PYR-cells. Lastly, we identified a microcircuit-wide coexpression network enriched in synaptic, bioenergetic, and oxidative stress response genes that correlated with UCMS-induced behaviors. Conclusions These findings suggest cell-specific deficits, microcircuit-wide synaptic reorganization, and a shift in cells regulating the cortical excitation-inhibition balance, suggesting increased coordinated regulation of PYR-cells by SST- and PV-cells.
