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Supplementary Table S2: qPCR primer for subcluster E genes

Supplementary Figure S1: Time-course expression analysis of LNCaP cells reveals dynamic and heterogeneous responses to androgen stimulation. Supplementary Figure S2: Cell cycle progression of LNCaP cells treated with or without R1881 after cell synchronization by double thymidine block (DTB). Supplementary Figure S3: The summary of aligned and unaligned single-cell RNA-seq reads counts. Supplementary Figure S4: Correlation of single-cell RNA-seq ensemble reads with representative bulk RNA-seq reads. Supplementary Figure S5: Venn diagrams illustrating the comparison of differentially expressed genes found in single- and bulk-cell LNCaP experiments. Supplementary Figure S6: The Mclust algorithm defines likely subgroups using a "model-based" approach. Supplementary Figure S7: Each cell within each subcluster exhibits a similar gene expression profile. Supplementary Figure S8: Gleason score and biochemical recurrence status compared to each subcluster''s gene expression profile. Supplementary Figure S9: Differential expression of 10 genes in LNCaP''s 8.1 subpopulation of cells. Supplementary Figure S10: High single-cell expression of 10 genes in PC3 similar to 12hr-R1881 LNCaP cells.

Increasing evidence suggests the presence of minor cell subpopulations in prostate cancer that are androgen independent and poised for selection as dominant clones after androgen deprivation therapy. In this study, we investigated this phenomenon by stratifying cell subpopulations based on transcriptome profiling of 144 single LNCaP prostate cancer cells treated or untreated with androgen after cell-cycle synchronization. Model-based clustering of 397 differentially expressed genes identified eight potential subpopulations of LNCaP cells, revealing a previously unappreciable level of cellular heterogeneity to androgen stimulation. One subpopulation displayed stem-like features with a slower cell doubling rate, increased sphere formation capability, and resistance to G2–M arrest induced by a mitosis inhibitor. Advanced growth of this subpopulation was associated with enhanced expression of 10 cell-cycle–related genes (CCNB2, DLGAP5, CENPF, CENPE, MKI67, PTTG1, CDC20, PLK1, HMMR, and CCNB1) and decreased dependence upon androgen receptor signaling. In silico analysis of RNA-seq data from The Cancer Genome Atlas further demonstrated that concordant upregulation of these genes was linked to recurrent prostate cancers. Analysis of receiver operating characteristic curves implicates aberrant expression of these genes and could be useful for early identification of tumors that subsequently develop biochemical recurrence. Moreover, this single-cell approach provides a better understanding of how prostate cancer cells respond heterogeneously to androgen deprivation therapies and reveals characteristics of subpopulations resistant to this treatment.Significance: Illustrating the challenge in treating cancers with targeted drugs, which by selecting for drug resistance can drive metastatic progression, this study characterized the plasticity and heterogeneity of prostate cancer cells with regard to androgen dependence, defining the character or minor subpopulations of androgen-independent cells that are poised for clonal selection after androgen-deprivation therapy. Cancer Res; 78(4); 853–64. ©2017 AACR.

PDF file - 1049K, Supplementary Figure S1. Summarized sequencing reads and coverage of MBDCap-seq Supplementary Figure S2. Reproducibility test of MBDCap-seq Supplementary Figure S3. Validation of MBDCap-seq by MassARRAY analysis Supplementary Figure S4. Distribution of differentially methylated regions (DMRs) in endometrial tumors relative to normal control Supplementary Figure S5. Network analysis of differential methylation loci by using Steiner-tree analysis Supplementary Figure S6. DNA methylation distribution in early and late stage of the TCGA endometrial cancer cohort Supplementary Figure S7. Relative expression of BMP genes with EGF treatment in the presence or absence of PI3K/AKT and Raf (MAPK) inhibitors in endometrial cancer cells Supplementary Figure S8. Induction of invasion by EGF in AN3CA and HEC1A cell lines Supplementary Figure S9. Knockdown expression of BMP4 and BMP7 in RL95-2 cells Supplementary Figure S10. Relative expression of BMPs and BMPRs in normal endometrial cell and endometrial cancer cell lines Supplementary Figure S11. Microfluidics-based PCR analysis of EMT gene panel in RL95-2 cells with or without EGF treatment Supplementary Figure S12. Knockdown expression of EpCAM by different shRNA sequences in RL95-2 cells Supplementary Figure S13. Proposed model for EpICD mediated regulation of BMP genes by EGF Supplementary Table 1. Characteristics of endometrial cancer patients Supplemental Table 2. Summary of sequencing reads in endometrial tumors an normal controls Supplementary Table 3. Differentially methylated promoter CpG islands in recurrent relative to non-recurrent tumors Supplementary Table 4. List of primer sequences Supplementary Table 5. List of siRNA and shRNA sequences

Purpose: Epigenetic regulation by promoter methylation plays a key role in tumorigenesis. Our goal was to investigate whether altered DNA methylation signatures associated with oncogenic signaling delineate biomarkers predictive of endometrial cancer recurrence.Experimental Design: Methyl-CpG-capture sequencing was used for global screening of aberrant DNA methylation in our endometrial cancer cohort, followed by validation in an independent The Cancer Genome Atlas (TCGA) cohort. Bioinformatics as well as functional analyses in vitro, using RNA interference (RNAi) knockdown, were performed to examine regulatory mechanisms of candidate gene expression and contribution to aggressive phenotype, such as epithelial–mesenchymal transition (EMT).Results: We identified 2,302 hypermethylated loci in endometrial tumors compared with control samples. Bone morphogenetic protein (BMP) family genes, including BMP1, 2, 3, 4, and 7, were among the frequently hypermethylated loci. Interestingly, BMP2, 3, 4, and 7 were less methylated in primary tumors with subsequent recurrence and in patients with shorter disease-free interval compared with nonrecurrent tumors, which was validated and associated with poor survival in the TCGA cohort (BMP4, P = 0.009; BMP7, P = 0.007). Stimulation of endometrial cancer cells with epidermal growth factor (EGF) induced EMT and transcriptional activation of these genes, which was mediated by the epithelial cell adhesion molecule (EpCAM). EGF signaling was implicated in maintaining the promoters of candidate BMP genes in an active chromatin configuration and thus subject to transcriptional activation.Conclusions: Hypomethylation signatures of candidate BMP genes associated with EpCAM-mediated expression present putative biomarkers predictive of poor survival in endometrial cancer. Clin Cancer Res; 19(22); 6272–85. ©2013 AACR.

Summary: Background: Rheumatoid arthritis (RA) is an inflammatory disease that manifests as a preclinical stage of systemic autoimmunity followed by chronic progressive synovitis. Disease-associated genetic SNP variants predominantly map to non-coding, regulatory regions of functional importance in CD4 T cells, implicating these cells as key regulators. A better understanding of the epigenome of CD4 T cells holds the promise of providing information on the interaction between genetic susceptibility and exogenous factors. Methods: We mapped regions of chromatin accessibility using ATAC-seq in peripheral CD4 T cell subsets of patients with RA (n=18) and compared them to T cells from patients with psoriatic arthritis (n=11) and age-matched healthy controls (n=10). Transcripts of selected genes were quantified using qPCR. Findings: RA-associated epigenetic signatures were identified that in part overlapped between central and effector memory CD4 T cells and that were to a lesser extent already present in naïve cells. Sites more accessible in RA were highly enriched for the motif of the transcription factor (TF) CTCF suggesting differences in the three-dimensional chromatin structure. Unexpectedly, sites with reduced chromatin accessibility were enriched for motifs of TFs pertinent for T cell function. Most strikingly, super-enhancers encompassing RA-associated SNPs were less accessible. Analysis of selected transcripts and published DNA methylation patterns were consistent with this finding. The preferential loss in accessibility at these super-enhancers was seen in patients with high and low disease activity and on a variety of immunosuppressive treatment modalities. Interpretation: Disease-associated genes are epigenetically less poised to respond in CD4 T cells from patients with established RA. Funding: This work was supported by I01 BX001669 from the Veterans Administration.

SummaryT cell aging is a complex process combining the emergence of cellular defects with activation of adaptive mechanisms. Generation of T cell memory is impaired, while a low-inflammatory state is induced, in part due to effector T cells. To determine whether age-associated changes in T cell fate decisions occur early after T cell activation, we profiled the longitudinal transcriptional and epigenetic landscape induced by TCR stimulation comparing naïve CD4+ T cells from young and older adults. In spite of attenuated TCR signaling, activation-induced remodeling of the epigenome increased with age, culminating in heightened BATF and BLIMP1 activity. Single cell studies, integrating ATAC-seq and RNA-seq data, identified increases in dysfunctional and in effector T cells and a decrease in BACH2-expressing memory cell precursors. STAT5 activation, in part due to a decline in HELIOS and aberrant IL-2 receptor expression, accounted for the induction of transcription factor networks favoring effector cell differentiation.

Significance PD-1+ TCF1+ stem-like CD8 T cells are critical for maintaining the T cell response during chronic viral infection and cancer, and provide the proliferative burst seen after PD-1 immunotherapy. These cells undergo a slow self-renewal and also give rise to the more terminally differentiated and exhausted CD8 T cells. Here we define the epigenetic landscape of the stem-like CD8 T cells and their more differentiated progeny. These 2 CD8 T cell subsets from chronically infected mice showed substantial differences, but also shared common features that were distinct from the epigenetic signature of effector and memory CD8 T cells generated after an acute viral infection. This information will be useful in targeting epigenetic changes to improve current immunotherapies., We have recently defined a novel population of PD-1 (programmed cell death 1)+ TCF1 (T cell factor 1)+ virus-specific CD8 T cells that function as resource cells during chronic LCMV infection and provide the proliferative burst seen after PD-1 blockade. Such CD8 T cells have been found in other chronic infections and also in cancer in mice and humans. These CD8 T cells exhibit stem-like properties undergoing self-renewal and also differentiating into the terminally exhausted CD8 T cells. Here we compared the epigenetic signature of stem-like CD8 T cells with exhausted CD8 T cells. ATAC-seq analysis showed that stem-like CD8 T cells had a unique signature implicating activity of HMG (TCF) and RHD (NF-κB) transcription factor family members in contrast to higher accessibility to ETS and RUNX motifs in exhausted CD8 T cells. In addition, regulatory regions of the transcription factors Tcf7 and Id3 were more accessible in stem-like cells whereas Prdm1 and Id2 were more accessible in exhausted CD8 T cells. We also compared the epigenetic signatures of the 2 CD8 T cell subsets from chronically infected mice with effector and memory CD8 T cells generated after an acute LCMV infection. Both CD8 T cell subsets generated during chronic infection were strikingly different from CD8 T cell subsets from acute infection. Interestingly, the stem-like CD8 T cell subset from chronic infection, despite sharing key functional properties with memory CD8 T cells, had a very distinct epigenetic program. These results show that the chronic stem-like CD8 T cell program represents a specific adaptation of the T cell response to persistent antigenic stimulation.

SUMMARY Induction of protective vaccine responses, governed by the successful generation of antigen-specific anti-bodies and long-lived memory T cells, is increasingly impaired with age. Regulation of the T cell proteome by a dynamic network of microRNAs is crucial to T cell responses. Here, we show that activation-induced upregulation of miR-21 biases the transcrip-tome of differentiating T cells away from memory T cells and toward inflammatory effector T cells. Such a transcriptome bias is also characteristic of T cell responses in older individuals who have increased miR-21 expression and is reversed by antagonizing miR-21. miR-21 targets negative feedback circuits in several signaling pathways. The concerted, sustained activity of these signaling path-ways in miR-21high T cells disfavors the induction of transcription factor networks involved in memory cell differentiation. Our data suggest that curbing miR-21 upregulation or activity in older individuals may improve their ability to mount effective vaccine responses., Graphical Abstract, In Brief A hallmark of the aging immune system is its failure to induce long-lived memory. Kim et al. report that increased expression of miR-21 in naive T cells from older individuals sustains signaling in the MAPK and AKT-mTORC pathways, disfavoring induction of transcription factor networks involved in memory cell generation.

Combination therapy with PD-1 blockade and IL-2 is highly effective during chronic lymphocytic choriomeningitis virus infection(1). Here we examine the underlying basis for this synergy. We show that PD-1 + IL-2 combination therapy, unlike PD-1 monotherapy, dramatically changes the differentiation program of the PD-1(+)TCF-1(+) stem-like CD8(+) T cells and results in the generation of transcriptionally and epigenetically distinct effector CD8(+) T cells that resemble highly functional effector CD8(+) T cells seen after an acute viral infection. The generation of these qualitatively superior CD8(+) T cells that mediate viral control underlies the synergy between PD-1 and IL-2. Our results show that the PD-1(+)TCF-1(+) stem-like CD8(+) T cells, also referred to as precursors of exhausted CD8(+) T cells, are not fate-locked into the exhaustion program and their differentiation trajectory can be changed by IL-2 signals. These virus-specific effector CD8(+) T cells emerging from the stem-like CD8(+) T cells after combination therapy expressed increased levels of the high affinity IL-2 trimeric (CD25, CD122, CD132) receptor. This was not seen after PD-1 blockade alone. Finally, we show that CD25 engagement with IL-2 plays an important role in the observed synergy between IL-2 cytokine and PD-1 blockade. Either blocking CD25 with an antibody or using a mutated version of IL-2 that does not bind CD25 but still binds CD122/CD132 almost completely abrogated the synergistic effects seen after PD-1 + IL-2 combination therapy. There is currently considerable interest in PD-1 + IL-2 combination therapy for patients with cancer(2,3) and our fundamental studies defining the underlying mechanisms of how IL-2 synergizes with PD-1 blockade should inform these human translational studies.

Rheumatoid arthritis (RA) and psoriatic arthritis (PsA) are two distinct autoimmune diseases that manifest with chronic synovial inflammation. Here, we show that CD4+ T cells from patients with RA and PsA have increased expression of the pore-forming calcium channel component ORAI3, thereby increasing the activity of the arachidonic acid-regulated calcium-selective (ARC) channel and making T cells sensitive to arachidonic acid. A similar increase does not occur in T cells from patients with systemic lupus erythematosus. Increased ORAI3 transcription in RA and PsA T cells is caused by reduced IKAROS expression, a transcriptional repressor of the ORAI3 promoter. Stimulation of the ARC channel with arachidonic acid induces not only a calcium influx, but also the phosphorylation of components of the T cell receptor signaling cascade. In a human synovium chimeric mouse model, silencing ORAI3 expression in adoptively transferred T cells from patients with RA attenuates tissue inflammation, while adoptive transfer of T cells from healthy individuals with reduced expression of IKAROS induces synovitis. We propose that increased ARC activity due to reduced IKAROS expression makes T cells more responsive and contributes to chronic inflammation in RA and PsA., ORAI3 is part of pore forming calcium channels involved in T cell activation. Here the authors show that there is increased expression of ORAI3 in T cells from patients with rheumatoid arthritis and that the transcription factor IKAROS negatively regulates the ORAI3 promoter, indicating a regulatory loop that can control auto-reactivity of T cells in these patients.

Healthy immune aging is in part determined by how well the sizes of naïve T cell compartments are being maintained with advancing age. Throughout adult life, replenishment largely derives from homeostatic proliferation of existing naïve and memory T cell populations. However, while the subpopulation composition of CD4 T cells is relatively stable, the CD8 T cell compartment undergoes more drastic changes with loss of naïve CD8 T cells and accumulation of effector T cells, suggesting that CD4 T cells are more resilient to resist age-associated changes. To determine the epigenetic basis for these differences in behaviors, we compared chromatin accessibility maps of CD4 and CD8 T cell subsets from young and old individuals and related the results to the expressed transcriptome. The dominant age-associated signatures resembled hallmarks of differentiation, which were more pronounced for CD8 naïve and memory than the corresponding CD4 T cell subsets, indicating that CD8 T cells are less able to keep cellular quiescence upon homeostatic proliferation. In parallel, CD8 T cells from old adults, irrespective of their differentiation state, displayed greater reduced accessibility to genes of basic cell biological function, including genes encoding ribosomal proteins. One possible mechanism is the reduced expression of the transcription factors YY1 and NRF1. Our data suggest that chromatin accessibility signatures can be identified that distinguish CD4 and CD8 T cells from old adults and that may confer the higher resilience of CD4 T cells to aging.

With increasing age, individuals are more vulnerable to viral infections such as with influenza or the SARS-CoV-2 virus. One age-associated defect in human T cells is the reduced expression of miR-181a. miR-181ab1 deficiency in peripheral murine T cells causes delayed viral clearance after infection, resembling human immune aging. Here we show that naive T cells from older individuals as well as miR-181ab1-deficient murine T cells develop excessive replication stress after activation, due to reduced histone expression and delayed S-phase cell cycle progression. Reduced histone expression was caused by the miR-181a target SIRT1 that directly repressed transcription of histone genes by binding to their promoters and reducing histone acetylation. Inhibition of SIRT1 activity or SIRT1 silencing increased histone expression, restored cell cycle progression, diminished the replication-stress response, and reduced the production of inflammatory mediators in replicating T cells from old individuals. Correspondingly, treatment with SIRT1 inhibitors improved viral clearance in mice with miR-181a-deficient T cells after LCMV infection. In conclusion, SIRT1 inhibition may be beneficial to treat systemic viral infection in older individuals by targeting antigen-specific T cells that develop replication stress due to miR-181a deficiency.

Adjuvant chemotherapy in breast cancer patients causes immune cell depletion at an age when the regenerative capacity is compromised. Successful regeneration requires the recovery of both quantity and quality of immune cell subsets. Although immune cell numbers rebound within a year after treatment, it is unclear whether overall compositional diversity is recovered. We investigated the regeneration of immune cell complexity by comparing peripheral blood mononuclear cells from breast cancer patients ranging from 1–5 years after chemotherapy with those of age-matched healthy controls using mass cytometry and T cell receptor sequencing. These data reveal universal changes in patients’ CD4(+) T cells that persisted for years and consisted of expansion of Th17-like CD4 memory populations with incomplete recovery of CD4(+) naive T cells. Conversely, CD8(+) T cells fully recovered within a year. Mechanisms of T cell regeneration, however, were unbiased, as CD4(+) and CD8(+) T cell receptor diversity remained high. Likewise, terminal differentiated effector memory cells were not expanded, indicating that regeneration was not driven by recognition of latent viruses. These data suggest that, while CD8(+) T cell immunity is successfully regenerated, the CD4 compartment may be irreversibly affected. Moreover, the bias of CD4 memory toward inflammatory effector cells may impact responses to vaccination and infection.

MicroRNAs have emerged as key regulators in T cell development, activation, and differentiation, with miR-181a having a prominent function. By targeting several signaling pathways, miR-181a is an important rheostat controlling T cell receptor (TCR) activation thresholds in thymic selection as well as peripheral T cell responses. A decline in miR-181a expression, due to reduced transcription of pri-miR-181a, accounts for T cell activation defects that occur with older age. Here we examine the transcriptional regulation of miR-181a expression and find a putative pri-miR-181a enhancer around position 198,904,300 on chromosome 1, which is regulated by a transcription factor complex including YY1. The decline in miR-181a expression correlates with reduced transcription of YY1 in older individuals. Partial silencing of YY1 in T cells from young individuals reproduces the signaling defects seen in older T cells. In conclusion, YY1 controls TCR signaling by upregulating miR-181a and dampening negative feedback loops mediated by miR-181a targets., MicroRNA miR-181a has been implicated in the regulation of T cell activation and development. Here the authors show that miR-181a is regulated by a transcription factor, YY1, with reduced YY1 expression linked to reduced miR-181a in old individuals, while silencing YY1 impairs T cell functions largely through influencing the expression of miR-181a targets.

Increasing evidence suggests the presence of minor cell subpopulations in prostate cancer that are androgen independent and poised for selection as dominant clones after androgen deprivation therapy. In this study, we investigated this phenomenon by stratifying cell subpopulations based on transcriptome profiling of 144 single LNCaP prostate cancer cells treated or untreated with androgen after cell-cycle synchronization. Model-based clustering of 397 differentially expressed genes identified eight potential subpopulations of LNCaP cells, revealing a previously unappreciable level of cellular heterogeneity to androgen stimulation. One subpopulation displayed stem-like features with a slower cell doubling rate, increased sphere formation capability, and resistance to G2–M arrest induced by a mitosis inhibitor. Advanced growth of this subpopulation was associated with enhanced expression of 10 cell-cycle–related genes (CCNB2, DLGAP5, CENPF, CENPE, MKI67, PTTG1, CDC20, PLK1, HMMR, and CCNB1) and decreased dependence upon androgen receptor signaling. In silico analysis of RNA-seq data from The Cancer Genome Atlas further demonstrated that concordant upregulation of these genes was linked to recurrent prostate cancers. Analysis of receiver operating characteristic curves implicates aberrant expression of these genes and could be useful for early identification of tumors that subsequently develop biochemical recurrence. Moreover, this single-cell approach provides a better understanding of how prostate cancer cells respond heterogeneously to androgen deprivation therapies and reveals characteristics of subpopulations resistant to this treatment. Significance: Illustrating the challenge in treating cancers with targeted drugs, which by selecting for drug resistance can drive metastatic progression, this study characterized the plasticity and heterogeneity of prostate cancer cells with regard to androgen dependence, defining the character or minor subpopulations of androgen-independent cells that are poised for clonal selection after androgen-deprivation therapy. Cancer Res; 78(4); 853–64. ©2017 AACR.

SUMMARY Generation of protective immunity to infections and vaccinations declines with age. Studies in healthy individuals have implicated reduced miR-181a expression in T cells as contributing to this defect. To understand the impact of miR-181a expression on antiviral responses, we examined LCMV infection in mice with miR-181ab1-deficient T cells. We found that miR-181a deficiency delays viral clearance, thereby biasing the immune response in favor of CD4 over CD8 T cells. Antigen-specific CD4 T cells in mice with miR-181a-deficient T cells expand more and have a broader TCR repertoire with preferential expansion of high-affinity T cells than in wild-type mice. Importantly, generation of antigen-specific miR-181a-deficient CD8 effector T cells is particularly impaired, resulting in lower frequencies of CD8 T cells in the liver even at time points when the infection has been cleared. Consistent with the mouse model, CD4 memory T cells in individuals infected with West Nile virus at older ages tend to be more frequent and of higher affinity., Graphical Abstract, In Brief T cell aging in humans is associated with progressive loss in miR-181a, the implications of which for antiviral immunity are unknown. Using mouse models, Kim et al. find that miR-181a deficiency in T cells reproduces many aging features including impaired effector T cell expansion, viral clearance, generation of tissue-residing T cells, and recall responses.

T cells are a heterogeneous population of cells that differ in their differentiation stages. Functional states are reflected in the epigenome that confers stability in cellular identity and is therefore important for naïve as well as memory T cell function. In many cellular systems, changes in chromatin structure due to alterations in histone expression, histone modifications and DNA methylation are characteristic of the aging process and cause or at least contribute to cellular dysfunction in senescence. Here, we review the epigenetic changes in T cells that occur with age and discuss them in the context of canonical epigenetic marks in aging model systems as well as recent findings of chromatin accessibility changes in T cell differentiation. Remarkably, transcription factor networks driving T cell differentiation account for many of the age-associated modifications in chromatin structures suggesting that loss of quiescence and activation of differentiation pathways are major components of T cell aging. Review on aging process in T cells is characterized by changes in chromatin structures, many of which resemble epigenetic modifications seen with differentiation.

Aging is associated with an increased susceptibility to infection and a failure to control latent viruses thought to be driven, at least in part, by alterations in CD8 T cell function. The aging T cell repertoire is characterized by an accumulation of effector CD8 T cells, many of which express the negative regulatory receptor CD85j. To define the biological significance of CD85j expression on CD8 T cells and to address the question whether presence of CD85j in older individuals is beneficial or detrimental for immune function, we examined the specific attributes of CD8 T cells expressing CD85j as well as the functional role of CD85j in antigen-specific CD8 T cell responses during immune aging. Here, we show that CD85j is mainly expressed by terminally differentiated effector (TEMRAs) CD8 T cells, which increase with age, in cytomegalovirus (CMV) infection and in males. CD85j+ CMV-specific cells demonstrate clonal expansion. However, TCR diversity is similar between CD85j+ and CD85j− compartments, suggesting that CD85j does not directly impact the repertoire of antigen-specific cells. Further phenotypic and functional analyses revealed that CD85j identifies a specific subset of CMV-responsive CD8 T cells that coexpress a marker of senescence (CD57) but retain polyfunctional cytokine production and expression of cytotoxic mediators. Blocking CD85j binding enhanced proliferation of CMV-specific CD8 T cells upon antigen stimulation but did not alter polyfunctional cytokine production. Taken together, these data demonstrate that CD85j characterizes a population of “senescent,” but not exhausted antigen-specific effector CD8 T cells and indicates that CD85j is an important checkpoint regulator controlling expansion of virus-specific T cells during aging. Inhibition of CD85j activity may be a mechanism to promote stronger CD8 T cell effector responses during immune aging.

The transcriptional repressor Bcl6 is a critical arbiter of Th cell fate, promoting the follicular Th lineage while repressing other Th cell lineages. Bcl6-deficient (Bcl6−/−) mice develop a spontaneous and severe Th2-type inflammatory disease, thus warranting assessment of Bcl6 in regulatory T cell (Treg) function. Bcl6−/− Tregs were competent at suppressing T cell proliferation in vitro and Th1-type colitogenic T cell responses in vivo. In contrast, Bcl6−/− Tregs strongly exacerbated lung inflammation in a model of allergic airway disease and promoted higher Th2 responses, including systemic upregulation of microRNA-21. Further, Bcl6−/− Tregs were selectively impaired at controlling Th2 responses, but not Th1 and Th17 responses, in mixed chimeras of Bcl6−/− bone marrow with Foxp3−/− bone marrow. Bcl6−/− Tregs displayed increased levels of the Th2 transcription factor Gata3 and other Th2 and Treg genes. Bcl6 potently repressed Gata3 transcriptional transactivation, providing a mechanism for the increased expression of Th2 genes by Bcl6−/− Tregs. Gata3 has a critical role in regulating Foxp3 expression and functional fitness of Tregs; however, the signal that regulates Gata3 and restricts its transactivation of Th2 cytokines in Tregs has remained unexplored. Our results identify Bcl6 as an essential transcription factor regulating Gata3 activity in Tregs. Thus, Bcl6 represents a crucial regulatory layer in the Treg functional program that is required for specific suppression of Gata3 and Th2 effector responses by Tregs.

Methylation is one of the essential epigenetic modifications to the DNA, which is responsible for the precise regulation of genes required for stable development and differentiation of different tissue types. Dysregulation of this process is often the hallmark of various diseases like cancer. Here, we outline one of the recent sequencing techniques, Methyl-Binding DNA Capture sequencing (MBDCap-seq), used to quantify methylation in various normal and disease tissues for large patient cohorts. We describe a detailed protocol of this affinity enrichment approach along with a bioinformatics pipeline to achieve optimal quantification. This technique has been used to sequence hundreds of patients across various cancer types as a part of the 1,000 methylome project (Cancer Methylome System).

Aberrant DNA methylation at promoters is often linked to tumorigenesis. But many aspects of DNA methylation remain unexplored, including the individual roles of distal and gene body methylation, as well as their collaborative roles with promoter methylation. Here we performed a MBD-seq analysis on prostate specimens classified into low, high and very high risk group based on Gleason score and TNM stages. We identified gene sets with differential methylation regions (DMRs) in Distal, TSS, gene body and TES. To understand the collaborative roles, TSS was compared with the other three DMRs, resulted in 12 groups of genes with collaborative differential methylation patterns (CDMPs). We found several groups of genes that show opposite methylation patterns in Distal and Genic regions compared to TSS region and in general they are differentially expressed genes (DEGs) in tumors in TCGA RNA-seq data. IPA (Ingenuity Pathway Analysis) reveals AR/TP53 signaling network to be a major signaling pathway and survival analysis indicates genes subsets significantly associated with prostate cancer recurrence. Our results suggest that DNA methylation in Distal and Genic regions also plays critical roles in contributing to prostate tumorigenesis and may act either positively or negatively with TSSs to alter gene regulation in tumors.

Early postnatal exposures to Bisphenol A (BPA) and genistein (GEN) have been reported to predispose for and against mammary cancer, respectively, in adult rats. Since the changes in cancer susceptibility occurs in the absence of the original chemical exposure, we have investigated the potential of epigenetics to account for these changes. DNA methylation studies reveal that prepubertal BPA exposure alters signaling pathways that contribute to carcinogenesis. Prepubertal exposure to GEN and BPA + GEN revealed pathways involved in maintenance of cellular function, indicating that the presence of GEN either reduces or counters some of the alterations caused by the carcinogenic properties of BPA. We subsequently evaluated the potential of epigenetic changes in the rat mammary tissues to predict survival in breast cancer patients via the Cancer Genomic Atlas (TCGA). We identified 12 genes that showed strong predictive values for long-term survival in estrogen receptor positive patients. Importantly, two genes associated with improved long term survival, HPSE and RPS9, were identified to be hypomethylated in mammary glands of rats exposed prepuberally to GEN or to GEN + BPA respectively, reinforcing the suggested cancer suppressive properties of GEN.

Background Recent genome-wide analysis has shown that DNA methylation spans long stretches of chromosome regions consisting of clusters of contiguous CpG islands or gene families. Hypermethylation of various gene clusters has been reported in many types of cancer. In this study, we conducted methyl-binding domain capture (MBDCap) sequencing (MBD-seq) analysis on a breast cancer cohort consisting of 77 patients and 10 normal controls, as well as a panel of 38 breast cancer cell lines. Results Bioinformatics analysis determined seven gene clusters with a significant difference in overall survival (OS) and further revealed a distinct feature that the conservation of a large gene cluster (approximately 70 kb) metallothionein-1 (MT1) among 45 species is much lower than the average of all RefSeq genes. Furthermore, we found that DNA methylation is an important epigenetic regulator contributing to gene repression of MT1 gene cluster in both ERα positive (ERα+) and ERα negative (ERα−) breast tumors. In silico analysis revealed much lower gene expression of this cluster in The Cancer Genome Atlas (TCGA) cohort for ERα + tumors. To further investigate the role of estrogen, we conducted 17β-estradiol (E2) and demethylating agent 5-aza-2′-deoxycytidine (DAC) treatment in various breast cancer cell types. Cell proliferation and invasion assays suggested MT1F and MT1M may play an anti-oncogenic role in breast cancer. Conclusions Our data suggests that DNA methylation in large contiguous gene clusters can be potential prognostic markers of breast cancer. Further investigation of these clusters revealed that estrogen mediates epigenetic repression of MT1 cluster in ERα + breast cancer cell lines. In all, our studies identify thousands of breast tumor hypermethylated regions for the first time, in particular, discovering seven large contiguous hypermethylated gene clusters. Electronic supplementary material The online version of this article (doi:10.1186/s13148-015-0045-9) contains supplementary material, which is available to authorized users.

Purpose: Epigenetic regulation by promoter methylation plays a key role in tumorigenesis. Our goal was to investigate whether altered DNA methylation signatures associated with oncogenic signaling delineate biomarkers predictive of endometrial cancer recurrence. Experimental Design: Methyl-CpG-capture sequencing was used for global screening of aberrant DNA methylation in our endometrial cancer cohort, followed by validation in an independent The Cancer Genome Atlas (TCGA) cohort. Bioinformatics as well as functional analyses in vitro, using RNA interference (RNAi) knockdown, were performed to examine regulatory mechanisms of candidate gene expression and contribution to aggressive phenotype, such as epithelial–mesenchymal transition (EMT). Results: We identified 2,302 hypermethylated loci in endometrial tumors compared with control samples. Bone morphogenetic protein (BMP) family genes, including BMP1, 2, 3, 4, and 7, were among the frequently hypermethylated loci. Interestingly, BMP2, 3, 4, and 7 were less methylated in primary tumors with subsequent recurrence and in patients with shorter disease-free interval compared with nonrecurrent tumors, which was validated and associated with poor survival in the TCGA cohort (BMP4, P = 0.009; BMP7, P = 0.007). Stimulation of endometrial cancer cells with epidermal growth factor (EGF) induced EMT and transcriptional activation of these genes, which was mediated by the epithelial cell adhesion molecule (EpCAM). EGF signaling was implicated in maintaining the promoters of candidate BMP genes in an active chromatin configuration and thus subject to transcriptional activation. Conclusions: Hypomethylation signatures of candidate BMP genes associated with EpCAM-mediated expression present putative biomarkers predictive of poor survival in endometrial cancer. Clin Cancer Res; 19(22); 6272–85. ©2013 AACR.

Prostate tumors shed circulating tumor cells (CTCs) into the blood stream. Increased evidence shows that CTCs are often present in metastatic prostate cancer and can be alternative sources for disease profiling and prognostication. Here we postulate that CTCs expressing genes related to epithelial-mesenchymal transition (EMT) are strong predictors of metastatic prostate cancer.A microfiltration system was used to trap CTCs from peripheral blood based on size selection of large epithelial-like cells without CD45 leukocyte marker. These cells individually retrieved with a micromanipulator device were assessed for cell membrane physical properties using atomic force microscopy. Additionally, 38 CTCs from eight prostate cancer patients were used to determine expression profiles of 84 EMT-related and reference genes using a microfluidics-based PCR system.Increased cell elasticity and membrane smoothness were found in CTCs compared to noncancerous cells, highlighting their potential invasiveness and mobility in the peripheral circulation. Despite heterogeneous expression patterns of individual CTCs, genes that promote mesenchymal transitioning into a more malignant state, including IGF1, IGF2, EGFR, FOXP3, and TGFB3, were commonly observed in these cells. An additional subset of EMT-related genes (e.g., PTPRN2, ALDH1, ESR2, and WNT5A) were expressed in CTCs of castration-resistant cancer, but less frequently in castration-sensitive cancer.The study suggests that an incremental expression of EMT-related genes in CTCs is associated with metastatic castration-resistant cancer. Although CTCs represent a group of highly heterogeneous cells, their unique EMT-related gene signatures provide a new opportunity for personalized treatments with targeted inhibitors in advanced prostate cancer patients.

Endometrial cancer (EC) is the most common gynecologic malignancy, with approximately 20% of EC patients developing advanced stage recurrent tumors and frequent metastasis. Our goal was to investigate whether DNA methylation signatures associated with low promoter methylation (hypomethylation) and specific oncogenic signaling delineate predictive markers of endometrial cancer recurrence. Global screening by Methyl-CpG-capture sequencing revealed aberrant DNA methylation in our endometrial cancer cohort and identified a subset of bone morphogenetic protein family (BMP1, 2, 3, 4, and 7) exhibiting frequent hypomethylation in primary tumors with subsequent recurrence compared with non-recurrent tumors. This epigenetic signature correlated with poor survival and was validated in The Cancer Genome Atlas endometrial cancer cohort. Our functional studies also implicated epidermal growth factor receptor (EGFR) pathway in the transcriptional activation of these BMPs and inducing epithelial-mesenchymal transition (EMT). In addition to AKT and MAPK, the epithelial cell adhesion molecule (EpCAM) mediated these actions by EGFR. EpCAM involvement in cancer progression includes nuclear co-translocation of its intracellular domain EpICD with Lef-1 complexes and targeting oncogene promoter activation. In this study, EGF stimulated EpICD-Lef-1 binding on BMP genes accompanied with histone active modification marks. EpICD knockdown resulted in increased repressive histone marks and DNA methylation at these loci, suggesting that EpICD occupancy is involved in their epigenetic modification to an open transcriptional conformation. Knockdown of candidate BMPs led to decreased endometrial cancer cell invasiveness, implicating them in aggressive growth. Extending our studies, we performed ChIP-Seq analysis to identify global regulation by the EpICD-Lef-1 complexes in endometrial cancer. Interestingly, under basal levels only about 28% of loci targeted by either EpICD or Lef-1 were commonly targeted by EpICD-Lef-1, with common targets increasing to about 50% in 24 hrs and 73% in 48 hrs post EGF treatment. This indicates that EGFR signaling stimulates a time-course dependent enrichment of EpICD-Lef-1 convergence on target loci. Our initial studies of these EpICD target pathways included genes with cell adhesion functions. Future studies on the regulation of the EpICD-Lef-1 regulated genes and their mechanisms of action in aggressive endometrial cancer will provide a better understanding of this gene network in endometrial cancer. Hypomethylation signatures of candidate loci in this regulatory network may present putative predictive markers of poor survival and which may be used to tailor individualized therapy. Citation Format: Ya-Ting Hsu, Fei Gu, Yi-Wen Huang, Joseph Liu, Jianhua Ruan, Rui-Lan Huang, Chiou-Miin Wang, Chun-Liang Chen, Rohit R. Jadhav, Yao Wang, Victor X. Jin, Hung-Cheng Lai, David G. Mutch, Paul J. Goodfellow, Ian M. Thompson, Nameer B. Kirma, Tim H.M. Huang. EpCAM-mediated hypomethylation of BMP and cell adhesion genes is associated with advanced endometrial cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1376. doi:10.1158/1538-7445.AM2014-1376

Approximately 30% of prostate cancer (PCa) patients who receive androgen-deprivation therapy experience disease progression, including bone metastasis, in 18-36 months. Clinical diagnosis of this castration resistance is primarily based on a continuous rise in serum PSA levels during therapy. However, the underlying disease progression predates the clinical onset of castration resistance by many months. The clinical challenge is to distinguish indolent vs aggressive cancer for better disease management. During the prostate cancer progression, malignant circulating tumor cells (CTC) shed from the primary site into the bloodstream through epigenetic modifications and an epithelial-to-mesenchymal transition (EMT). Evidence suggests that increased CTCs are present in the blood of castration-resistant PCa patients and can be obtained through routine phlebotomy. EMT changes of CTCs present a great potential for disease prognosis, treatment stratification and subsequent disease monitoring. We have recently established the combined microfiltration-micromanipulation system (CM2S) to enrich prostate CTCs from blood as published in The Prostate. Our preliminary studies based on a relatively small sample size show that CTCs isolated from advanced PCa patients often lose the typical features of prostate epithelial cells and display incremental EMT-related gene expression signatures, higher elasticity and smoother membrane features. Furthermore, incremental expression of these genes and particular nanomechanical features in CTCs are associated with castration-resistant and metastatic PCa. In this study, we would like expand the sample size to clinically develop this methodology. CTCs were isolated from patients' blood (∼15 ml) using microfiltration system (ScreenCell). We analyzed castration-sensitive (CS) and castration-resistant (CR) PCa cells and CTCs using high throughput microfluidic single-cell RT-PCR. The data were subject to hierarchical clustering, violin plot and Ingenuity Pathway Analysis (IPA). Increased expression of EMT genes was found in CR PCa cells and CTCs as compared to CS counterparts. IPA indicated that these EMT genes are closely related to AKT, β-catenin, Myc and NFκB pathways. Some of CTCs isolated from patients were subject to nanomechanical and nanochemical analysis using PeakForce QNM Catalyst atomic force microscopy (AFM) (Bruker). CTCs of CR patients are about 3 fold more elastic and 7 fold more adherent than CTCs of CS patients. Additionally, CTCs of CR patients are about 3 fold more deformable than CTCs of CS patients. In conclusion, we confirmed our previous study with a larger patient sample size. The increased expression of EMT-related genes and nanomechanical and nanochemical phenotypes in CTCs are potential biomarkers for detection of the castration-resistant PCa, treatment stratification and subsequent disease monitoring. Citation Format: Chun-Liang Chen, Pawel Osmulski, Devalingam Mahalingam, Aaron M. Horning, Rohit R. Jadhav, Anna D. Louie, Chiou-Miin Wang, Tim H.-M. Huang. Epithelial-to-mesenchymal markers of circulating tumor cells for detection of castration-resistant prostate cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5588. doi:10.1158/1538-7445.AM2014-5588