Regulatory T-cell Infiltration Research Articles

CD25+FOXP3+CD45RA− regulatory T-cell infiltration as a prognostic biomarker for endometrial carcinoma

BackgroundRegulatory T (Treg) cells reportedly play crucial roles in tumor angiogenesis as well as antitumor immunity. In order to explore their therapeutic potential, we investigated the precise prognostic impact of Treg markers in endometrial carcinoma.MethodsWe performed multiplexed immunofluorescence and quantitative image analyses of CD25, FOXP3, CTLA4, and CD45RA in tumor specimens from 176 consecutive patients treated at our institution for primary endometrial carcinomas. Bioinformatics analyses were further conducted to corroborate the findings.ResultsHigh CD25+, FOXP3+, and CD25+FOXP3+CD45RA− stromal cell counts correlated with better overall survival (OS) (p = 0.00019, 0.028 and 0.0012) and MSI-high (p = 0.015, 0.016 and 0.047). High CD45RA+ stromal cell count was associated with superficial myometrial invasion (p = 0.0038). Bioinformatics survival analysis by Kaplan-Meier plotter showed that high CD25, FOXP3, CTLA4, and CD45RA mRNA expressions correlated with better OS (p = 0.046, 0.00042, 0.000044, and 0.0022). Univariate and multivariate analyses with various clinicopathologic prognostic factors indicated that high CD25+ or CD25+FOXP3+CD45RA− stromal cell count was significant and independent for favorable OS (p = 0.0053 and 0.0015). We subsequently analyzed the correlations between the multiplexed immunofluorescence results and treatment-free interval (TFI) after primary chemotherapy in recurrent cases, finding no significant associations. Further analysis revealed that high ratio of CD25+ : CD8+ cell count or CD25+FOXP3+CD45RA− : CD8+ cell count correlated with longer TFI (p = 0.021 and 0.021).ConclusionThe current observations suggest that the balance between CD25+ or CD25+FOXP3+CD45RA− cells and CD8+ cells, corresponding to promoting or inhibiting effect on tumor angiogenesis, affect tumor chemosensitivity leading to prognostic significance. CD25+FOXP3+CD45RA− effector Treg tumor infiltration may serve as a useful prognostic biomarker and a potential target for immunotherapeutic manipulation of tumor chemosensitivity by novel management for advanced/recurrent endometrial carcinomas.

SOX12 Facilitates Hepatocellular Carcinoma Progression and Metastasis through Promoting Regulatory T-Cells Infiltration and Immunosuppression.

Despite the success of immunotherapy in treating hepatocellular carcinoma (HCC), HCC remains a severe threat to health. Here, a crucial transcription factor, SOX12, is revealed that induces the immunosuppression of liver tumor microenvironment. Overexpressing SOX12 in HCC syngeneic models increases intratumoral regulatory T-cell (Treg) infiltration, decreases CD8+T-cell infiltration, and hastens HCC metastasis. Hepatocyte-specific SOX12 knockout attenuates DEN/CCl4-induced HCC progression and metastasis, whereas hepatocyte-specific SOX12 knock-in accelerates these effects. Mechanistically, SOX12 transcriptionally activates C-C motif chemokine ligand 22 (CCL22) expression to promote the recruitment and suppressive activity of Tregs. Moreover, SOX12 transcriptionally upregulates CD274 expression to suppress CD8+T-cell infiltration. Either knockdown of CCL22 or PD-L1 dampens SOX12-mediated HCC metastasis. Blocking of CC chemokine receptor 4 (CCR4), a receptor for CCL22, by inhibitor C-021 or Treg-specific knockout of CCR4 inhibits SOX12-mediated HCC metastasis. Transforming growth factor-β1 (TGF-β1)/TGFβR1-Smad2/3/4 is identified as a key upstream signaling for SOX12 overexpression in HCC cells. Combining C-021 or TGFβR1 inhibitor galunisertib with anti-PD-L1 exhibits an enhanced antitumor effect in two HCC models. Collectively, the findings demonstrate that SOX12 contributes to HCC immunosuppression through the CCL22/CCR4-Treg and PD-L1-CD8+T axes. Blocking of CCR4 or TGFβR1 improves the efficacy of anti-PD-L1 in SOX12-mediated HCC.

Low ACADM expression predicts poor prognosis and suppressive tumor microenvironment in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) represents a highly frequent renal cancer subtype. However, medium-chain acyl-CoA dehydrogenase (ACADM) encodes an important enzyme responsible for fatty acid β-oxidation (FAO) and its association with prognosis and immunity in cancers has rarely been reported. Therefore, the present work focused on exploring ACADM’s expression and role among ccRCC cases. We used multiple public databases and showed the hypo levels of ACADM protein and mRNA within ccRCC. Additionally, we found that ACADM down-regulation showed a remarkable relation to the advanced stage, high histological grade, as well as dismal prognostic outcome. As suggested by Kaplan–Meier curve analysis, cases showing low ACADM levels displayed shorter overall survival (OS) as well as disease-free survival (DFS). Moreover, according to univariate/multivariate Cox regression, ACADM-mRNA independently predicted the prognosis of ccRCC. In addition, this work conducted immunohistochemistry for validating ACADM protein expression and its prognostic role in ccRCC samples. KEGG and GO analyses revealed significantly enriched genes related to ACADM expression during fatty acid metabolism. The low-ACADM group with more regulatory T-cell infiltration showed higher expression of immune negative regulation genes and higher TIDE scores, which might contribute to poor response to immunotherapies. In conclusion, our results confirmed that downregulated ACADM predicted a poor prognosis for ccRCC and a poor response to immunotherapy. Our results provide important data for developing immunotherapy for ccRCC.

Abstract 1570: Lipid metabolism alterations promote TNBC metastasis and immunotherapy resistance via PD-L1 internalization and signaling

Abstract Programmed death-ligand 1, PD-L1 (CD274), is an immune checkpoint protein upregulated by cancer cells to facilitate immune evasion. PD-L1 also performs oncogenic functions within cancer cells, but the underlying mechanisms of PD-L1 internalization and signaling remain largely unknown. Here, we report a new mechanism whereby altered ceramide metabolism via ceramide synthase 4 (CerS4) drives PD-L1 internalization to potentiate a TGFβ/Shh/β-catenin signaling axis to drive triple-negative breast cancer (TNBC) migration and metastasis. In response to altered ceramide metabolism, we observed that PD-L1 is internalized via clathrin-mediated endocytosis and depends on S278/S279 in its cytoplasmic domain. Once internalized, PD-L1 directly interacts with Caprin-1, an RNA-binding protein previously unassociated with PD-L1 signaling. Through our analysis of clinical specimens, we established a positive association between PD-L1/Caprin-1 interaction and metastatic progression in human TNBC. In terms of mechanism, we determined that the PD-L1/Caprin-1 complex plays a pivotal role in mediating CerS4-dependent cell migration. This complex selectively binds and stabilizes mRNA, resulting in heightened TGFβ/Shh/β-catenin signaling. Conversely, CerS4 restoration in metastatic TNBC cells impaired cellular migration and the interaction between PD-L1 and Caprin-1. Genetic depletion of CerS4 enhanced lung metastasis derived from 4T1 orthotopic allografts and transgenic MMTV-PyMT breast tumors concomitant with PD-L1/Caprin-1 interaction and TGFβ/Shh/β-catenin signaling. Bioinformatics analysis of clinical datasets was used to validate the impact of the CerS4/PD-L1/Caprin-1 axis on metastatic progression in human TNBC. In alignment with enhanced tumor progression, CerS4 depletion in tumors promoted regulatory T-cell infiltration, suggesting an immunosuppressive tumor microenvironment (TME). Treatment with sonidegib, an FDA-approved Hedgehog (Hh) inhibitor, effectively prevented PD-L1 internalization and its interaction with Caprin-1. We hypothesized that sonidegib could synergize with immune checkpoint blockade to sensitize TNBC to immunotherapy, which typically has low response rates. Sonidegib, in combination with αPD-L1 therapy, was significantly more effective in controlling TNBC primary and metastatic tumor growth, especially when Cers4 was downregulated, compared to αPD-L1 monotherapy. Our data also suggested that this potent anti-tumor effect was due to immunotherapy sensitization after combined flow cytometry, multiplexed immunofluorescence, and bulk RNA-sequencing analyses. Altogether, these findings demonstrate a mechanism to define intracellular PD-L1 signaling in response to altered ceramide metabolism, providing a new therapeutic strategy to target TNBC metastasis and improve response to immunotherapy. Citation Format: Wyatt O. Wofford, Jisun Kim, Dosung Kim, Alhaji H. Janneh, Han Gyul Lee, F. Cansu Atilgan, Natalia Oleinik, Elizabeth Hill, Ozge Saatci, Salih Gencer, Paramita Chakraborty, Shikhar Mehrotra, Ozgur Sahin, Besim Ogretmen. Lipid metabolism alterations promote TNBC metastasis and immunotherapy resistance via PD-L1 internalization and signaling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1570.

Fibroblast activation protein (FAP) as a prognostic biomarker in multiple tumors and its therapeutic potential in head and neck squamous cell carcinoma.

Fibroblast activation protein (FAP), a cell surface serine protease, plays roles in tumor invasion and immune regulation. However, there is currently no pan-cancer analysis of FAP. Objective: We aimed to assess the pan-cancer expression profile of FAP, its molecular function, and its potential role in head and neck squamous cell carcinoma (HNSC). We analyzed gene expression, survival status, immune infiltration, and molecular functional pathways of FAP in The Cancer Genome Atlas (TCGA) and Genotype Tissue Expression (GTEx) tumors. Furthermore, to elucidate the role of FAP in HNSC, we performed proliferation, migration, and invasion assays post-FAP overexpression or knock-down. FAP expression was elevated in nine tumor types and was associated with poor survival in eight of them. In the context of immune infiltration, FAP expression negatively correlated with CD8+ T-cell infiltration in five tumor types and positively with regulatory T-cell infiltration in four tumor types. Our enrichment analysis highlighted FAP's involvement in the PI3K-Akt signaling pathway. In HNSC cells, FAP overexpression activated the PI3K-Akt pathway, promoting tumor proliferation, migration, and invasion. Conversely, FAP knockdown showed inhibitory effects. Our study unveils the association of FAP with poor tumor prognosis across multiple cancers and highlights its potential as a therapeutic target in HNSC.

Inducing the Abscopal Effect in Liver Cancer Treatment: The Impact of Microwave Ablation Power Levels and PD-1 Antibody Therapy.

Microwave ablation (MWA) is an effective treatment for liver cancer (LC), but its impact on distant tumors remains to be fully elucidated. This study investigated the abscopal effects triggered by MWA treatment of LC, at different power levels and with or without combined immune checkpoint inhibition (ICI). We established a mouse model with bilateral subcutaneous LC and applied MWA of varied power levels to ablate the right-sided tumor, with or without immunotherapy. Left-sided tumor growth was monitored to assess the abscopal effect. Immune cell infiltration and distant tumor neovascularization were quantified via immunohistochemistry, revealing insights into the tumor microenvironment and neovascularization status. Th1- and Th2-type cytokine concentrations in peripheral blood were measured using ELISA to evaluate systemic immunological changes. It was found that MWA alone, especially at lower power, promoted distant tumor growth. On the contrary, combining high-power MWA with anti-programmed death (PD)-1 therapy promoted CD8+ T-cell infiltration, reduced regulatory T-cell infiltration, upregulated a Th1-type cytokine (TNF-α) in peripheral blood, and inhibited distant tumor growth. In summary, combining high-power MWA with ICI significantly enhances systemic antitumor immune responses and activates the abscopal effect, offering a facile and robust strategy for improving treatment outcomes.

Chronic chromosome instability induced by Plk1 results in immune suppression in breast cancer

Chromosome instability (CIN) contributes to resistance to therapies and tumor evolution. Although natural killer (NK) cells can eliminate cells with complex karyotypes, high-CIN human tumors have an immunosuppressive phenotype. To understand which CIN-associated molecular features alter immune recognition during tumor evolution, we overexpress Polo-like kinase 1 (Plk1) in a Her2+ breast cancer model. These high-CIN tumors activate a senescence-associated secretory phenotype (SASP), upregulate PD-L1 and CD206, and induce non-cell-autonomous nuclear factor κB (NF-κβ) signaling, facilitating immune evasion. Single-cell RNA sequencing from pre-neoplastic mammary glands unveiled the presence of Arg1+ macrophages, NK cells with reduced effector functions, and increased resting regulatory Tcell infiltration. We further show that high PLK1-expressing human breast tumors display gene expression patterns associated with SASP, NF-κβ signaling, and immune suppression. These findings underscore the need to understand the immune landscape in CIN tumors to identify more effective therapies, potentially combining immune checkpoint or NF-κβ inhibitors with current treatments.

A Nanodrug Simultaneously Inhibits Pancreatic Stellate Cell Activation and Regulatory T cell Infiltration to Promote the Immunotherapy of Pancreatic Cancer.

Pancreatic ductal adenocarcinoma (PDAC) is characterized by a dense extracellular matrix flooded with immune suppressive cells, resulting in extremely poor clinical response to immunotherapy. It has been revealed that the activation of pancreatic stellate cells (PSCs) makes considerable contributions to the immunological "cold" tumor microenvironment (TME). Herein, we developed a polyamino acid-based nanodrug incorporating the PSC activation inhibitor calcipotriol and anti-CXCL12 siRNA. The nanodrug was easily prepared with a small particle size and is capable of penetrating pancreatic tumors to inactivate PSCs and downregulate CXCL12. The in vivo results of orthotopic pancreatic tumor treatment demonstrated that codelivery of calcipotriol and anti-CXCL12 siRNA remodeled the PDAC TME with reduced extracellular matrix and decreased immunosuppressive T cells. Eventually, the infiltration of cytotoxic T cells was increased, thereby acting with immune checkpoint blockade (ICB) therapy for immunologically "cold" pancreatic tumors. In the present study, we propose a promising paradigm to improve the immunotherapy outcome of PDAC using nanodrugs that synchronously inhibit PSC activation and regulatory T-cell infiltration. STATEMENT OF SIGNIFICANCE: Pancreatic ductal adenocarcinoma (PDAC) is characterized by a dense extracellular matrix (ECM) that impedes the tumor infiltration of therapeutic agents and cytotoxic T lymphocytes, resulting in a poor clinical response to immunotherapy. In the present study, we proposed a promising approach for enhanced immunotherapy of pancreatic cancer. Specifically, a nanodrug incorporating calcipotriol and anti-CXCL12 siRNA was synthesized to synchronously inactivate matrix-producing pancreatic stellate cells and suppress the infiltration of regulatory T cells. The reduced ECM removed the pathological barrier, preventing nanodrug penetration and effector T-cell infiltration, leading to a conversion of the immunosuppressive "cold" microenvironment to a "hot" microenvironment, which eventually boosted the immunotherapy of anti-PD-1 antibodies in pancreatic cancer.

Upregulation of TUBG1 expression promotes hepatocellular carcinoma development.

Tubulin γ-1 (TUBG1) is a highly conserved component of the centrosome and its deregulation is involved in the development of several types of cancer. However, the role of TUBG1 in hepatocellular carcinoma (HCC) remains unclear. In this study, we found that TUBG1 was upregulated in human HCC cells and tissues and that TUBG1 upregulation was associated with promoter hypomethylation in HCC tissues. TUBG1 knockdown suppressed the proliferation, invasion, and migration of HCC cells. While TUBG1 expression was positively correlated with CD4 + memory T lymphocyte infiltration, it was negatively correlated with CD4 + regulatory T-cell infiltration in human HCC tissues. Furthermore, TUBG1 expression was positively correlated with the expression of genes involved in cell division. Noticeably, high expression of TUBG1 was associated with poor prognosis in patients with HCC. Overall, our findings revealed that TUBG1 promotes hepatocarcinogenesis by increasing proliferation, invasion, and migration of HCC cells and may regulate T lymphocyte infiltration. The current findings provide important insights into TUBG1 regulation in HCC, which could provide new therapeutic targets for hepatocarcinoma which has a very high incidence and mortality rate worldwide.

Epithelial-Mesenchymal Transition Phenotype and Peritumoral Immune Cell Infiltration in Advanced Biliary Tract Cancer.

This study evaluated the clinical implications of epithelial-mesenchymal transition (EMT) markers and peritumoral immune cell infiltration in patients with biliary tract cancer (BTC) treated with gemcitabine plus cisplatin (GemCis). Forty-five patients with advanced BTC who received GemCis were included as the study population. We conducted multiplex immunohistochemistry and examined EMT markers and their correlations with immune cell infiltrate at the invasive tumor margin. Study population was subdivided into two groups: twenty-four patients with overall survival (OS) less than 10 months (short-term survivor group, SS) and 21 with OS of 20 months or longer (long-term survivor group, LS). The density of tumor cells expressing epithelial marker E-cadherin (E-cadherin+ CK+) at the invasive tumor margin tended to be higher in the LS group than that in the SS group (p=0.065). The density of tumor cells expressing mesenchymal marker vimentin (vimentin+ CK+) was significantly higher in the SS group than that in the LS group (p=0.021). The density of E-cadherin- vimentin+ tumor cells (E-cadherin- vimentin+ CK+) was also significantly higher in the SS group (p=0.020). The density of OX40 expressing cells was significantly higher in the SS group compared to that in the LS group (p=0.006). The density of vimentin-expressing tumor cells was positively correlated with FoxP3+ CD4+ regulatory T-cells (r=0.29, p=0.047) and OX40+ cells (r=0.48, p<0.001). EMT-related features were enriched in BTC patients with poor survival outcomes and associated with regulatory T-cell infiltration.

High tumor hexokinase-2 expression promotes a pro-tumorigenic immune microenvironment by modulating CD8+/regulatory T-cell infiltration

BackgroundRelationship between cancer cell glycolysis and the landscape of tumor immune microenvironment in human cancers was investigated.MethodsForty-one fresh lung adenocarcinoma (ADC) tissues were analyzed using flow cytometry for comprehensive immunoprofiling. Formalin-fixed tissues were immunostained for hexokinase-2 (HK2) to assess cancer cell glycolysis. For validation, formalin-fixed tissues from 375 lung ADC, 118 lung squamous cell carcinoma (SqCC), 338 colon ADC, and 78 lung cancer patients treated with anti-PD-1/PD-L1 immunotherapy were immunostained for HK2, CD8, and FOXP3.ResultsBased on immunoprofiling of lung ADC, HK2 tumor expression was associated with the composition of lymphoid cells rather than myeloid cells. High HK2 tumor expression was associated with immunosuppressive/pro-tumorigenic features, especially decreased ratio of CD8 + T-cells to Tregs (rho = −0.415, P = 0.012). This correlation was also confirmed in four different cohorts including lung ADC and SqCC, colon ADC, and the immunotherapy cohort (rho = −0.175~-0.335, all P < 0.05). A low CD8 + T-cell to Treg ratio was associated with poor progression-free survival and overall survival in lung SqCC patients, and a shorter overall survival in the immunotherapy cohort (all, P < 0.05).ConclusionAn increase in HK2 expression may contribute to shaping the immunosuppressive/pro-tumorigenic tumor microenvironment by modulating the CD8 + T-cell to Treg ratio. Targeting tumor HK2 expression might be a potential strategy for enhancing anti-tumor immunity.

Inhibition of NF-κB DNA Binding Suppresses Myeloma Growth via Intracellular Redox and Tumor Microenvironment Modulation.

Multiple myeloma is a plasma cell malignancy that is still largely incurable, despite considerable progress in recent years. NF-κB is a well-established therapeutic target in multiple myeloma, but none of the currently available treatment options offer direct, specific pharmacologic targeting of NF-κB transcriptional activity. Thus, we designed a novel direct NF-κB inhibitor (IT848) as a drug candidate with strong potential for clinical translation and conducted comprehensive in vitro and in vivo mechanistic studies in multiple myeloma cell lines, primary multiple myeloma cells, xenograft models, and immunocompetent mouse models of multiple myeloma. Here, we show that IT848 inhibits NF-κB activity through inhibition of DNA binding of all five NF-κB subunits. IT848 treatment of multiple myeloma cell lines and patient samples inhibited proliferation and induced caspase-dependent and independent apoptosis. In addition to direct NF-κB inhibitory effects, IT848 treatment altered the redox homeostasis of multiple myeloma cells through depletion of the reduced glutathione pool, selectively inducing oxidative stress in multiple myeloma but not in healthy cells. Multiple myeloma xenograft studies confirmed the efficacy of IT848 as single agent and in combination with bortezomib. Furthermore, IT848 significantly improved survival when combined with programmed death protein 1 inhibition, and correlative immune studies revealed that this clinical benefit was associated with suppression of regulatory T-cell infiltration of the bone marrow microenvironment. In conclusion, IT848 is a potent direct NF-κB inhibitor and inducer of oxidative stress specifically in tumor cells, displaying significant activity against multiple myeloma cells in vitro and in vivo, both as monotherapy as well as in combination with bortezomib or immune checkpoint blockade.

FGFBP1 as a potential biomarker predicting bacillus Calmette–Guérin response in bladder cancer

Accurate prediction of Bacillus Calmette–Guérin (BCG) response is essential to identify bladder cancer (BCa) patients most likely to respond sustainably, but no molecular marker predicting BCG response is available in clinical routine. Therefore, we first identified that fibroblast growth factor binding protein 1 (FGFBP1) was upregulated in failures of BCG therapy, and the increased FGFBP1 had a poor outcome for BCa patients in the E-MTAB-4321 and GSE19423 datasets. These different expression genes associated with FGFBP1 expression are mainly involved in neutrophil activation, neutrophil-mediated immunity, and tumor necrosis factor-mediated signal pathways in biological processes. A significant positive correlation was observed between FGFBP1 expression and regulatory T-cell (Treg) infiltration by the Spearman correlation test in the BCG cohort (r = 0.177) and The Cancer Genome Atlas (TCGA) cohort (r = 0.176), suggesting that FGFBP1 may influence the response of BCa patients to BCG immunotherapy through immune escape. Though FGFBP1 expression was positively correlated with the expressions of PD-L1, CTLA4, and PDCD1 in TCGA cohort, a strong association between FGFBP1 and PD-L1 expression was only detected in the BCG cohort (r = 0.750). Furthermore, elevated FGFBP1 was observed in BCa cell lines and tissues in comparison to corresponding normal controls by RT-qPCR, Western blotting, and immunohistochemical staining. Increased FGFBP1 was further detected in the failures than in the responders by immunohistochemical staining. Notably, FGFBP1 is positively associated with PD-L1 expression in BCa patients with BCG treatment. To sum up, FGFBP1 in BCa tissue could be identified as a promising biomarker for the accurate prediction of BCG response in BCa.

Targeting Indoleamine Dioxygenase and Tryptophan Dioxygenase in Cancer Immunotherapy: Clinical Progress and Challenges.

Indoleamine 2.3-dioxygenases (IDO1/2) and tryptophan 2.3-dioxygenase (TDO) are the initial and rate-limiting enzymes in tryptophan metabolism, which play an essential role in mediating immunosuppression in tumor microenvironment. Accumulating evidence has indicated that both IDO1 and TDO are highly expressed in many malignant tumors, and their expression is generally associated with reduced tumor-infiltrating immune cells, increased regulatory T-cell infiltration, as well as cancer progression and poor prognosis for malignancies. A large number of IDO1 and TDO inhibitors have been screened or synthesized in the last two decades. Thus far, at least 12 antagonists targeting IDO1 and TDO have advanced to clinical trials. In this account, we conducted a comprehensive review of the development of IDO1 and TDO inhibitors in cancer immunotherapy, particularly their clinical research progress, and presented the current challenges and corresponding solutions.

Identification of hub biomarkers and immune cell infiltration in polymyositis and dermatomyositis.

Objective: Polymyositis (PM) and dermatomyositis (DM) are heterogeneous disorders. However, the etiology of PM/DM development has not been thoroughly clarified.Methods: Gene expression data of PM/DM were obtained from Gene Expression Omnibus. We used robust rank aggregation (RRA) to identify differentially expressed genes (DEGs). Gene Ontology functional enrichment and pathway analyses were used to investigate potential functions of the DEGs. Weighted gene co-expression network analysis (WGCNA) was used to establish a gene co-expression network. CIBERSORT was utilized to analyze the pattern of immune cell infiltration in PM/DM. Protein–protein interaction (PPI) network, Venn, and association analyses between core genes and muscle injury were performed to identify hub genes. Receiver operating characteristic analyses were executed to investigate the value of hub genes in the diagnosis of PM/DM, and the results were verified using the microarray dataset GSE48280.Results: Five datasets were included. The RRA integrated analysis identified 82 significant DEGs. Functional enrichment analysis revealed that immune function and the interferon signaling pathway were enriched in PM/DM. WGCNA outcomes identified MEblue and MEturquoise as key target modules in PM/DM. Immune cell infiltration analysis revealed greater macrophage infiltration and lower regulatory T-cell infiltration in PM/DM patients than in healthy controls. PPI network, Venn, and association analyses of muscle injury identified five putative hub genes: TRIM22, IFI6, IFITM1, IFI35, and IRF9.Conclusions: Our bioinformatics analysis identified new genetic biomarkers of the pathogenesis of PM/DM. We demonstrated that immune cell infiltration plays a pivotal part in the occurrence of PM/DM.

In This Issue

In This Issue

Transcription Elongation Machinery Is a Druggable Dependency and Potentiates Immunotherapy in Glioblastoma Stem Cells.

Glioblastoma (GBM) is the most lethal primary brain cancer characterized by therapeutic resistance, which is promoted by GBM stem cells (GSC). Here, we interrogated gene expression and whole-genome CRISPR/Cas9 screening in a large panel of patient-derived GSCs, differentiated GBM cells (DGC), and neural stem cells (NSC) to identify master regulators of GSC stemness, revealing an essential transcription state with increased RNA polymerase II-mediated transcription. The YY1 and transcriptional CDK9 complex was essential for GSC survival and maintenance in vitro and in vivo. YY1 interacted with CDK9 to regulate transcription elongation in GSCs. Genetic or pharmacologic targeting of the YY1-CDK9 complex elicited RNA m6A modification-dependent interferon responses, reduced regulatory T-cell infiltration, and augmented efficacy of immune checkpoint therapy in GBM. Collectively, these results suggest that YY1-CDK9 transcription elongation complex defines a targetable cell state with active transcription, suppressed interferon responses, and immunotherapy resistance in GBM. SIGNIFICANCE: Effective strategies to rewire immunosuppressive microenvironment and enhance immunotherapy response are still lacking in GBM. YY1-driven transcriptional elongation machinery represents a druggable target to activate interferon response and enhance anti-PD-1 response through regulating the m6A modification program, linking epigenetic regulation to immunomodulatory function in GBM.This article is highlighted in the In This Issue feature, p. 275.

Infiltrating T-cell markers in cervical carcinogenesis: a systematic review and meta-analysis

BackgroundThe host adaptive immune response helps determine which cervical HPV infections persist and progress to precancer and cancer, and systematic characterisation of T-cell infiltration would help inform key steps in cervical carcinogenesis.MethodsA systematic review and meta-analysis were conducted of infiltrating T-cells in normal cervix, low-grade lesions, high-grade lesions, and invasive cancers including epithelial, stromal, and total tissue and the following markers: CD3, CD4, CD8, FoxP3, CD25, and the CD4:CD8 ratio. An additional qualitative review summarised longitudinal data on associations between infiltrating T-cells and cervical disease persistence, regression, progression, or prognosis.ResultsThere were fewer CD3+, CD4+, and CD8+ cells in cervical lesions and more cells in cancers compared to normal epithelium. FoxP3 and CD25+ regulatory T-cell infiltration is high in persistent and precancerous lesions, and longitudinal data show improved outcomes with lower regulatory T-cell levels.ConclusionsSuccessful immune evasion may reduce T-cell infiltration in HPV infected and precancerous epithelium, while invasive cancers are highly immunogenic, and regulatory T-cell infiltration increases with cervical disease progression. Understanding these factors may have prognostic value and could aid in novel treatment development and clinical guidelines, but published data are highly heterogeneous and leave important gaps to be filled by future studies.

Diminished CD68+ Cancer-Associated Fibroblast Subset Induces Regulatory T-Cell (Treg) Infiltration and Predicts Poor Prognosis of Oral Squamous Cell Carcinoma Patients

Although cancer-associated fibroblasts (CAFs) are crucial stromal cells, characterizing their heterogeneity is far from complete. This study reports a novel subset of CAFs in oral squamous cell carcinoma (OSCC), which positively expressed CD68, the classic marker of macrophages. The spatial and temporal distribution of the CD68+ CAF subset of OSCC (n = 104) was determined by CD68/actin alpha 2, smooth muscle (ACTA2+; α-SMA) immunohistochemistry of serial sections. The CD68+ α-SMA+ CAF subset was elevated from dysplasia to OSCC. Moreover, although both the tumor center and invasive front harbor an abundant CD68+ CAF subset, patients with low-CD68+ CAFs in the tumor center showed more recurrence after operation and shorter survival time, indicating the different function of CD68+ CAFs in tumor initiation and progression. Functional analysis in the OSCC-CAF co-culture system found knockdown of CD68 did not change the phenotype of CAFs, tumor growth, or migration. Unexpectedly, low-CD68+ CAFs were associated with aberrant immune balance. A high proportion of tumor-supportive Tregs was found in patients with low-CD68+ CAFs. Mechanistically, knockdown of CD68 in CAFs contributed to the up-regulation of chemokine CCL17 and CCL22 of tumor cells to enhance Treg recruitment. Thus, up-regulated CD68+ fibroblasts participate in tumor initiation, but the low-CD68+ CAF subset in OSCC is conducive to regulatory T-cell (Treg) recruitment in the tumor microenvironment and contribute to poor prognosis of OSCC patients.

Overexpression of molecule GRP94 favors tumor progression in lung adenocarcinoma by interaction with regulatory T cells.

BackgroundEndoplasmic reticulum stress exists within a tumor. Glucose‐regulated protein 94 (GRP94) is a stress‐induced chaperone protein involved in tumor development and progression. Its role in myeloma, colon cancer, and other tumors has been confirmed, but its role in lung cancer is unclear. This study aimed to determine the role of GRP94 in lung cancer progression and prognostic prediction.MethodsImmunohistochemical staining of GRP94 in human lung adenocarcinoma (AD) and corresponding normal tissue was performed, and its relationship with FOXP3+ regulatory T‐cell (Treg) infiltration analyzed. We investigated the role of GRP94 in the behavior of lung AD cells by inhibiting GRP94 expression in A549 cells. Western blotting was used to detect the TGF‐β/SMAD2 signaling molecules and explore the possible molecular mechanism of GRP94.ResultsGRP94 mRNA (encoded by HSP90B1) and protein levels were upregulated and elevated, respectively, in lung AD compared to normal lung tissues. High GRP94 expression was associated with an advanced disease stage and poor survival. There was a positive correlation between GRP94 expression and FOXP3+ Treg infiltration into lung AD tissues. Our results confirm that GRP94 knockdown inhibits cell proliferation and promotes cell apoptosis by increasing caspase‐7 and CHOP levels in lung AD cells. TGF‐β and SMAD2 protein levels were decreased after GRP94 depletion.ConclusionsOur study revealed that that GRP94 expression in lung AD favors tumor progression and predicts poor prognosis. The oncogenic role of GRP94 may involve inducing Treg infiltration by promoting the TGF‐β signaling pathway.Key points GRP94 protein levels were elevated in lung AD tissues compared to normal lung tissues. The high expression of GRP94 in lung AD favors tumor progression and predicts poor prognosis.The oncogenic role of the molecule GRP94 may involve the stimulation of Treg infiltration via promotion of the TGF‐β signaling pathway.