RESUMEN
Over the past decades, accumulating evidence suggests that the gut microbiome exerts a key role in Alzheimer's disease (AD). The Alzheimer's Association Workgroup is updating the diagnostic criteria for AD, which changed the profiles and categorization of biomarkers from "AT(N)" to "ATNIVS." Previously, most of studies focus on the correlation between the gut microbiome and amyloid beta deposition ("A"), the initial AD pathological feature triggering the "downstream" tauopathy and neurodegeneration. However, limited research investigated the interactions between the gut microbiome and other AD pathogenesis ("TNIVS"). In this review, we summarize current findings of the gut microbial characteristics in the whole spectrum of AD. Then, we describe the association of the gut microbiome with updated biomarker categories of AD pathogenesis. In addition, we outline the gut microbiome-related therapeutic strategies for AD. Finally, we discuss current key issues of the gut microbiome research in the AD field and future research directions. HIGHLIGHTS: The new revised criteria for Alzheimer's disease (AD) proposed by the Alzheimer's Association Workgroup have updated the profiles and categorization of biomarkers from "AT(N)" to "ATNIVS." The associations of the gut microbiome with updated biomarker categories of AD pathogenesis are described. Current findings of the gut microbial characteristics in the whole spectrum of AD are summarized. Therapeutic strategies for AD based on the gut microbiome are proposed.
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Enfermedad de Alzheimer , Biomarcadores , Microbioma Gastrointestinal , Enfermedad de Alzheimer/microbiología , Enfermedad de Alzheimer/diagnóstico , Humanos , Microbioma Gastrointestinal/fisiologíaRESUMEN
THEMIS plays an indispensable role in T cells, but its mechanism of action has remained highly controversial. Using the systematic proximity labeling methodology PEPSI, we identify THEMIS as an uncharacterized substrate for the phosphatase SHP1. Saturated mutagenesis assays and mass spectrometry analysis reveal that phosphorylation of THEMIS at the evolutionally conserved Tyr34 residue is oppositely regulated by SHP1 and the kinase LCK. Similar to THEMIS-/- mice, THEMISY34F/Y34F knock-in mice show a significant decrease in CD4 thymocytes and mature CD4 T cells, but display normal thymic development and peripheral homeostasis of CD8 T cells. Mechanistically, the Tyr34 motif in THEMIS, when phosphorylated upon T cell antigen receptor activation, appears to act as an allosteric regulator, binding and stabilizing SHP1 in its active conformation, thus ensuring appropriate negative regulation of T cell antigen receptor signaling. However, cytokine signaling in CD8 T cells fails to elicit THEMIS Tyr34 phosphorylation, indicating both Tyr34 phosphorylation-dependent and phosphorylation-independent roles of THEMIS in controlling T cell maturation and expansion.
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Péptidos y Proteínas de Señalización Intercelular , Timocitos , Ratones , Animales , Ratones Noqueados , Timocitos/metabolismo , Receptores de Antígenos de Linfocitos T , Transducción de SeñalRESUMEN
Comprehensive molecular analyses of metastatic hepatocellular carcinoma (HCC) are lacking. Here, we generate multi-omic profiling of 257 primary and 176 metastatic regions from 182 HCC patients. Primary tumors rich in hypoxia signatures facilitated polyclonal dissemination. Genomic divergence between primary and metastatic HCC is high, and early dissemination is prevalent. The remarkable neoantigen intratumor heterogeneity observed in metastases is associated with decreased T cell reactivity, resulting from disruptions to neoantigen presentation. We identify somatic copy number alterations as highly selected events driving metastasis. Subclones without Wnt mutations show a stronger selective advantage for metastasis than those with Wnt mutations and are characterized by a microenvironment rich in activated fibroblasts favoring a pro-metastatic phenotype. Finally, metastases without Wnt mutations exhibit higher enrichment of immunosuppressive B cells that mediate terminal exhaustion of CD8+ T cells via HLA-E:CD94-NKG2A checkpoint axis. Collectively, our results provide a multi-dimensional dissection of the complex evolutionary process of metastasis.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Linfocitos T CD8-positivos/patología , Multiómica , Mutación , Microambiente Tumoral/genéticaRESUMEN
In lung adenocarcinoma (LUAD), the appearance of morphologically diverse tumor regions, termed histological patterns, is closely associated with disease progression and lymph node metastasis. However, the molecular characteristics of the histological patterns in LUAD and the underlying molecular evolutionary mechanisms between the histological patterns in primary tumors and lymph node metastases are poorly understood. Here, we re-analyzed the large TCGA-LUAD dataset and depicted a comprehensive profiling of the genome and transcriptome across the histological patterns in LUAD. Tumor phylogenetic trajectory analysis suggested that the complex glands is more apt to metastasize to the lymph node. Further deconvolution of the tumor microenvironment demonstrated that the complex glands had a higher infiltration of cancer-associated fibroblasts (CAFs). Single-cell transcriptome profiling of complex glands pattern identified a novel CAF subtype co-expressing fibroblast activation protein-alpha (FAP) and stimulator of interferon genes (STING). Moreover, our data demonstrated that FAP is an important downstream effector of STING in CAFs. In summary, our results provide the basis for the development of innovative therapeutic guidelines and intervention strategies for LUAD patients.
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Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Humanos , Filogenia , Regulación Neoplásica de la Expresión Génica , Biomarcadores de Tumor/genética , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/patología , Metástasis Linfática , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Microambiente Tumoral/genéticaRESUMEN
Tumor associated macrophages (TAMs) play an important role in tumorigenesis, development and anti-cancer drug therapy. However, very few epigenetic compounds have been elucidated to affect tumor growth by educating TAMs in the tumor microenvironment (TME). Herein, we identified that EZH2 performs a crucial role in the regulation of TAMs infiltration and protumoral polarization by interacting with human breast cancer (BC) cells. We showed that EZH2 inhibitors-treated BC cells induced M2 macrophage polarization in vitro and in vivo, while EZH2 knockdown exhibited the opposite effect. Mechanistically, inhibition of EZH2 histone methyltransferase alone by EZH2 inhibitors in breast cancer cells could reduce the enrichment of H3K27me3 on CCL2 gene promoter, elevate CCL2 transcription and secretion, contributing to the induction of M2 macrophage polarization and recruitment in TME, which reveal a potential explanation behind the frustrating results of EZH2 inhibitors against breast cancer. On the contrary, EZH2 depletion led to DNA demethylation and subsequent upregulation of miR-124-3p level, which inhibited its target CCL2 expression in the tumor cells, causing arrest of TAMs M2 polarization. Taken together, these data suggested that EZH2 can exert opposite regulatory effects on TAMs polarization through its enzymatic or non-enzymatic activities. Our results also imply that the effect of antitumor drugs on TAMs may affect its therapeutic efficacy, and the combined application with TAMs modifiers should be warranted to achieve great clinical success.
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Neoplasias de la Mama , Neoplasias de la Mama/patología , Línea Celular Tumoral , Quimiocina CCL2/metabolismo , Proteína Potenciadora del Homólogo Zeste 2/genética , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Femenino , Humanos , Macrófagos/metabolismo , Microambiente Tumoral/genética , Macrófagos Asociados a Tumores , Regulación hacia ArribaRESUMEN
Programmed cell death protein 1 (PD-1) checkpoint blockade therapy requires the CD28 co-stimulatory receptor for CD8+ T cell expansion and cytotoxicity. However, CD28 expression is frequently lost in exhausted T cells and during immune senescence, limiting the clinical benefits of PD-1 immunotherapy in individuals with cancer. Here, using a cereblon knockin mouse model that regains in vivo T cell response to lenalidomide, an immunomodulatory imide drug, we show that lenalidomide reinstates the anti-tumor activity of CD28-deficient CD8+ T cells after PD-1 blockade. Lenalidomide redirects the CRL4Crbn ubiquitin ligase to degrade Ikzf1 and Ikzf3 in T cells and unleashes paracrine interleukin-2 (IL-2) and intracellular Notch signaling, which collectively bypass the CD28 requirement for activation of intratumoral CD8+ T cells and inhibition of tumor growth by PD-1 blockade. Our results suggest that PD-1 immunotherapy can benefit from a lenalidomide combination when treating solid tumors infiltrated with abundant CD28- T cells.
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Antígenos CD28 , Receptor de Muerte Celular Programada 1 , Animales , Linfocitos T CD8-positivos , Factores Inmunológicos , Inmunoterapia/métodos , Lenalidomida/farmacología , RatonesRESUMEN
Cancer cells acquire genetic heterogeneity to escape from immune surveillance during tumor evolution, but a systematic approach to distinguish driver from passenger mutations is lacking. Here we investigate the impact of different immune pressure on tumor clonal dynamics and immune evasion mechanism, by combining massive parallel sequencing of immune edited tumors and CRISPR library screens in syngeneic mouse tumor model and co-culture system. We find that the core microRNA (miRNA) biogenesis and targeting machinery maintains the sensitivity of cancer cells to PD-1-independent T cell-mediated cytotoxicity. Genetic inactivation of the machinery or re-introduction of ANKRD52 frequent patient mutations dampens the JAK-STAT-interferon-γ signaling and antigen presentation in cancer cells, largely by abolishing miR-155-targeted silencing of suppressor of cytokine signaling 1 (SOCS1). Expression of each miRNA machinery component strongly correlates with intratumoral T cell infiltration in nearly all human cancer types. Our data indicate that the evolutionarily conserved miRNA pathway can be exploited by cancer cells to escape from T cell-mediated elimination and immunotherapy.
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Evasión Inmune , MicroARNs/metabolismo , Neoplasias , Animales , Línea Celular Tumoral , Quimiocinas/metabolismo , Heterogeneidad Genética , Humanos , Inmunoterapia , Interferón gamma , Ratones , Ratones Endogámicos C57BL , Ratones Desnudos , Neoplasias/genética , Fosfoproteínas Fosfatasas , Receptor de Muerte Celular Programada 1 , Transducción de Señal , Proteína 1 Supresora de la Señalización de Citocinas , Linfocitos TRESUMEN
Genome alteration signatures reflect recurring patterns caused by distinct endogenous or exogenous mutational events during the evolution of cancer. Signatures of single base substitution (SBS) have been extensively studied in different types of cancer. Copy number alterations are important drivers for the progression of multiple cancer. However, practical tools for studying the signatures of copy number alterations are still lacking. Here, a user-friendly open source bioinformatics tool "sigminer" has been constructed for copy number signature extraction, analysis and visualization. This tool has been applied in prostate cancer (PC), which is particularly driven by complex genome alterations. Five copy number signatures are identified from human PC genome with this tool. The underlying mutational processes for each copy number signature have been illustrated. Sample clustering based on copy number signature exposure reveals considerable heterogeneity of PC, and copy number signatures show improved PC clinical outcome association when compared with SBS signatures. This copy number signature analysis in PC provides distinct insight into the etiology of PC, and potential biomarkers for PC stratification and prognosis.
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Variaciones en el Número de Copia de ADN/genética , Análisis Mutacional de ADN , Genómica , Mutagénesis/genética , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/genética , Programas Informáticos , Biomarcadores de Tumor , Genoma Humano/genética , Inestabilidad Genómica , Humanos , Masculino , Pronóstico , Modelos de Riesgos Proporcionales , Neoplasias de la Próstata/clasificación , Análisis de Supervivencia , Resultado del TratamientoRESUMEN
Normalization with respect to sequencing depth is a crucial step in single-cell RNA sequencing preprocessing. Most methods normalize data using the whole transcriptome based on the assumption that the majority of transcriptome remains constant and are unable to detect drastic changes of the transcriptome. Here, we develop an algorithm based on a small fraction of constantly expressed genes as internal spike-ins to normalize single-cell RNA sequencing data. We demonstrate that the transcriptome of single cells may undergo drastic changes in several case study datasets and accounting for such heterogeneity by ISnorm (Internal Spike-in-like-genes normalization) improves the performance of downstream analyses.