Probes for INS

Choroid plexus (CP) tumors are rare primary brain neoplasms found most commonly in children and are thought to arise from CP epithelial cells. Sox2 is a transcription factor that not only plays a role in development in the ventricular zone, CP, and roof plate, but also contributes to cancer stemness, tumorigenesis, and drug resistance. Gene expression studies demonstrate aberrant Sox2 expression in human CP tumors, suggesting a role in tumor development. A subset of CP tumors exhibit abnormal NOTCH pathway activity. Using animal models, we previously show that sustained NOTCH activity leads to CP tumors. Immunofluorescence, RT-qPCR, and RNA scope assays have revealed increased Sox2 levels in NOTCH-driven CP tumors compared to wild type CP in mice. To investigate the role of Sox2 in CP tumors, we eliminated Sox2 expression in NOTCH-driven CP tumors. Loss of Sox2 almost completely blocked NOTCH-driven CP tumor growth in these mice, supporting a role for Sox2 in these tumors. Ciliation regulation is one proposed functional pathway for tumorigenesis in CP tumors. Using immunofluorescence assays for cilia (ARL13b) and aquaporin transport protein 1 (AQP1) in combination with super resolution microscopy, we observe a stark contrast between wild type CP epithelial cells which are multiciliated and homogeneously express AQP1, indicative of normal epithelial differentiation, compared to NOTCH-driven CP tumors consisting of mono-ciliated cells with loss of AQP1 expression. In Sox2-deficient NOTCH-driven CP tumors, we observe tumor cells remain mono-ciliated and AQP1-negative, indicating that Sox2 loss does not affect the ciliation machinery. Together this warrants further study into the mechanisms of Sox2 functions in CP tumors. By unraveling the role of Sox2 in CP tumors, we may better understand their origin and biology to ultimately design improved treatment options.

In recent years, chimeric antigen receptor-modified T cell (CAR T cell) therapy has proven to be a promising approach against cancer. Nonetheless, this approach still faces multiple challenges in eliminating solid tumors, one of which being the immunosuppressive tumor microenvironment (TME). Here, we demonstrated that knocking out the endogenous TGF-? receptor II (TGFBR2) in CAR T cells with CRISPR/Cas9 technology could reduce the induced Treg conversion and prevent the exhaustion of CAR T ce lls. Meanwhile, TGFBR2-edited CAR T cells had better in vivo tumor elimination efficacy, both in cell line-derived xenograft and patient-derived xenograft solid tumor models, whether administered locally or systemically. In addition, the TGFBR2-edited CAR T cells could eliminate contralaterally reinoculated xenografts in mice effectively, with an increased proportion of memory subsets within circulating CAR T cells of central memory and effector memory subsets. In conclusion, we greatly improved the in vitro and in vivo function of CAR T cells in TGF-?-rich tumor environments by knocking out endogenous TGFBR2 and propose a potentially new method to improve the efficacy of CAR T cell therapy for treating solid tumors

Immune checkpoint blockade is therapeutically successful for many patients across multiple cancer types. However, immune-related adverse events (irAE) frequently occur and can sometimes be life threatening. It is critical to understand the immunologic mechanisms of irAEs with the goal of finding novel treatment targets. Herein, we report our analysis of tissues from patients with irAE dermatitis using multiparameter immunofluorescence (IF), spatial transcriptomics, and RNA in situ hybridization (RISH). Skin psoriasis cases were studied as a comparison, as a known Th17-driven disease, and colitis was investigated as a comparison. IF analysis revealed that CD4+ and CD8+ tissue-resident memory T (TRM) cells were preferentially expanded in the inflamed portion of skin in cutaneous irAEs compared with healthy skin controls. Spatial transcriptomics allowed us to focus on areas containing TRM cells to discern functional phenotype and revealed expression of Th1-associated genes in irAEs, compared with Th17-asociated genes in psoriasis. Expression of PD-1, CTLA-4, LAG-3, and other inhibitory receptors was observed in irAE cases. RISH technology combined with IF confirmed expression of IFNγ, CXCL9, CXCL10, and TNFα in irAE dermatitis, as well as IFNγ within TRM cells specifically. The Th1-skewed phenotype was confirmed in irAE colitis cases compared with healthy colon.

Immunotherapy shows promising results and revolutionizes treatment of oral squamous cell carcinoma (OSCC). The immunologic microenvironment might have prognostic/predictive implications. Morphologic immunologic parameters (inflammatory infiltrate, stromal content, and budding activity [BA] [potentially indicating epithelial–mesenchymal transition]) were evaluated in 66 human primary therapy-naive OSCCs. Intraepithelial/stromal tumor-infiltrating lymphocytes (TILs; CD3+/CD4+/CD8+/CD4+FOXP3+/IL-17A+) were quantified, and ratios were calculated. HLA class I in tumor cells was evaluated immunohistochemically. mRNA in situ hybridization to detect IFN-γ was performed. Analysis was performed within invasive front (IF) and tumor center (TCe). Decreased HLA expression was associated with low TIL density, pronounced stromal content, and high BA; IFN-γ in TILs was correlated with high-density TILs; and IFN-γ in tumor cells was correlated with absence of BA (p < 0.05). Heterogeneity of parameters (TCe/IF) was rare. Low density of stromal CD4+FOXP3+ TILs within TCe and IF was identified as an independent prognostic factor for poor overall, disease-specific, and disease-free survival (p ≤ 0.011). Refining prognostication in OSCC with high-density CD4+FOXP3+ infiltrate within TCe and/or IF, high FOXP3:CD4 ratio was significantly correlated with favorable outcome in this subgroup. Furthermore, high-stromal CD8:CD4 ratio was found to be an independent favorable prognostic factor. In summary, immunologic parameters were closely intertwined. Morphologic correlates of epithelial–mesenchymal transition were associated with downregulation of HLA and decreased inflammation. Heterogeneity was infrequent. Low-density stromal CD4+FOXP3+ infiltrate within TCe and IF was an independent poor prognostic factor. Stratification of cases with high-density CD4+FOXP3+ TILs by FOXP3:CD4 ratio enables refinement of prognostication of this subgroup. CD8:CD4 ratio was identified as an independent prognostic factor.

Tumor-elicited inflammation confers tumorigenic properties, including cell death resistance, proliferation, or immune evasion. To focus on inflammatory signaling in tumors, we investigated linear ubiquitination, which enhances the nuclear factor-κB signaling pathway and prevents extrinsic programmed cell death under inflammatory environments. Here, we showed that linear ubiquitination was augmented especially in tumor cells around a necrotic core. Linear ubiquitination allowed melanomas to tolerate the hostile tumor microenvironment and to extend a necrosis-containing morphology. Loss of linear ubiquitination resulted in few necrotic lesions and growth regression, further leading to repression of innate anti-PD-1 therapy resistance signatures in melanoma as well as activation of interferon responses and antigen presentation that promote immune-mediated tumor eradication. Collectively, linear ubiquitination promotes tumor-specific tissue remodeling and the ensuing immune evasion.

Complex tissues such as tumors are comprised of multiple cells types and extracellular matrix. These cells include heterogenous populations of immune cells that infiltrate the tumors. Understanding the composition of these immune infiltrates in the tumor microenvironment (TME) can provide key insights to guide therapeutic intervention and predict treatment response. Thorough understanding of complex tissue dynamics and immune cell characterization requires a multi-omics approach. Simultaneous detection of RNA and protein using in situ hybridization (ISH) and immunohistochemistry/immunofluorescence (IHC/IF) can reveal cellular sources of secreted proteins, identify specific cell types, and visualize the spatial organization of cells within the tissue. However, a sequential workflow of ISH followed by IHC/IF frequently yields suboptimal protein detection because the protease digestion step in the ISH protocol resulting in poor antibody signal. Here we demonstrate a newly developed integrated ISH/IHC workflow that can substantially improve RNA-protein co-detection, enabling the visualization and characterization of tumor immune infiltrates at single-cell resolution with spatial and morphological context. To characterize tumor-infiltrating immune cells in a tumor TMA (tumor microarray), we utilized the RNAscope Multiplex Fluorescence assay in combination with the RNA-Protein Co-detection Kit to detect multiple immune cell populations. Immune cells such as macrophages, T cells and NK cells were detected using specific antibodies against CD68, CD8, CD4 and CD56, respectively. Precise characterization of these immune cells was achieved by using probes against targets such as CCL5, IFNG, GNZB, IL-12, NCR1 etc. that not only help in identifying specific immune cells but also assist in determining their activation states. We identified subsets of T cells such as CD4+ regulatory T cells and CD8+ cytotoxic T lymphocytes. Additionally, we were able to determine the activation states of CD8+ T cells by visualizing the expression of IFNG and GZMB. Furthermore, infiltrating macrophages were identified by detecting the CD68 protein expression while the M1 and M2 subsets were differentiated by detecting the M2-specific target RNA for CD163. Similarly, NK cells were identified by detecting CD56 protein in combination with CCL5 and NCR1 RNA expression. Interestingly, the degree of infiltration of the different immune cell populations varied based on the tumor type. In conclusion, the new RNAscope-ISH-IHC co-detection workflow and reagents enable optimized simultaneous visualization of RNA and protein targets by enhancing the compatibility of antibodies - including many previously incompatible antibodies - with RNAscope. This new workflow provides a powerful new approach to identifying and characterizing tumor infiltrating populations of immune cells.

IL11 is a member of the IL6 family of cytokines and signals through its cognate receptor subunits, IL11RA and glycoprotein 130 (GP130), to elicit biological responses via the JAK/STAT signaling pathway. IL11 contributes to cancer progression by promoting the survival and proliferation of cancer cells, but the potential immunomodulatory properties of IL11 signaling during tumor development have thus far remained unexplored. Here, we have characterized a role for IL11 in regulating CD4+ T cell-mediated antitumor responses. Absence of IL11 signaling impaired tumor growth in a sporadic mouse model of colon cancer and syngeneic allograft models of colon cancer. Adoptive bone marrow transfer experiments and in vivo depletion studies demonstrated that the tumor-promoting activity of IL11 was mediated through its suppressive effect on host CD4+ T cells in the tumor microenvironment. Indeed, when compared with Il11ra-proficient CD4+ T cells associated with MC38 tumors, their Il11ra-deficient counterparts displayed elevated expression of mRNA encoding the antitumor mediators IFNγ and TNFα. Likewise, IL11 potently suppressed the production of proinflammatory cytokines (IFNγ, TNFα, IL6, and IL12p70) by CD4+ T cells in vitro, which we corroborated by RNAscope analysis of human colorectal cancers, where IL11RAhigh tumors showed less IFNG and CD4 expression than IL11RAlow tumors. Therefore, our results ascribe a tumor cell-extrinsic immunomodulatory role to IL11 during colon cancer development that could be amenable to an anticytokine-based therapy.See related commentary by van der Burg.

Glioblastoma is believed to originate from nervous system cells; however, a putative origin from vessel-associated progenitor cells has not been considered. We deeply single-cell RNA-sequenced glioblastoma progenitor cells of 18 patients and integrated 710 bulk tumors and 73,495 glioma single cells of 100 patients to determine the relation of glioblastoma cells to normal brain cell types. A novel neural network-based projection of the developmental trajectory of normal brain cells uncovered two principal cell-lineage features of glioblastoma, neural crest perivascular and radial glia, carrying defining methylation patterns and survival differences. Consistently, introducing tumorigenic alterations in naïve human brain perivascular cells resulted in brain tumors. Thus, our results suggest that glioblastoma can arise from the brains' vasculature, and patients with such glioblastoma have a significantly poorer outcome.

Chimeric antigen receptor (CAR) T cell therapy has limited efficacy against solid tumors, and one major challenge is T cell exhaustion. To address this challenge, we performed a candidate gene screen using a hypofunction CAR-T cell model and found that depletion of basic leucine zipper ATF-like transcription factor (BATF) improved the antitumor performance of CAR-T cells. In different types of CAR-T cells and mouse OT-1 cells, loss of BATF endows T cells with improved resistance to exhaustion and superior tumor eradication efficacy. Mechanistically, we found that BATF binds to and up-regulates a subset of exhaustion-related genes in human CAR-T cells. BATF regulates the expression of genes involved in development of effector and memory T cells, and knocking out BATF shifts the population toward a more central memory subset. We demonstrate that BATF is a key factor limiting CAR-T cell function and that its depletion enhances the antitumor activity of CAR-T cells against solid tumors.

Zika virus (ZIKV) can infect human developing brain (HDB) progenitors resulting in epidemic microcephaly, whereas analogous cellular tropism offers treatment potential for the adult brain cancer, glioblastoma (GBM). We compared productive ZIKV infection in HDB and GBM primary tissue explants that both contain SOX2+ neural progenitors. Strikingly, although the HDB proved uniformly vulnerable to ZIKV infection, GBM was more refractory, and this correlated with an innate immune expression signature. Indeed, GBM-derived CD11b+ microglia/macrophages were necessary and sufficient to protect progenitors against ZIKV infection in a non-cell autonomous manner. Using SOX2+ GBM cell lines, we found that CD11b+-conditioned medium containing type 1 interferon beta (IFNβ) promoted progenitor resistance to ZIKV, whereas inhibition of JAK1/2 signaling restored productive infection. Additionally, CD11b+ conditioned medium, and IFNβ treatment rendered HDB progenitor lines and explants refractory to ZIKV. These findings provide insight into neuroprotection for HDB progenitors as well as enhanced GBM oncolytic therapies.