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Biology subjects

Colman, H.

Publications and source records attributed to Colman, H..

5 recordsLinked to original sources

NG2-targeting macrophages inhibit 3D invasion of patient-derived glioblastoma spheroids

Engineering macrophages with chimeric antigen receptors is emerging as a promising cancer therapeutic. Chimeric antigen receptor-expressing macrophages (CAR-Ms) engineered to recognize tumor-specific antigens have been shown to inhibit tumor growth and activate adaptive immune responses, leading to robust tumor control in animal studies. Based on this work, clinical trials have been initiated. While the trials have shown promise, challenges remain. The dynamic interactions between CAR-Ms and cancer cells and the exact mechanisms driving anti-tumor effects remain poorly defined. Defining the dynamic interactions between CAR-Ms and cancer cells will provide critical insights for optimizing future CAR-M design and improving therapeutic efficacy. We sought to directly visualize CAR-M interactions with glioblastoma cells at high-resolution and in real-time using CAR-Ms engineered to recognize Neural-Glial Antigen 2 (NG2), an antigen expressed on glioblastoma cells. Using patient-derived glioblastoma cells, we formed glioblastoma spheroids and embedded them in a 3D matrix together with CAR-Ms. Using time-lapse microscopy, as expected, we found that NG2-targeting CAR-Ms engulfed glioblastoma cells. However, excitingly, we found that NG2-targeting CAR-Ms blocked >85% of glioblastoma cell invasion in 3D. This inhibition of glioblastoma invasion was not due to a significant change in CAR-M polarization states. Together, these data suggest that NG2-targeting CAR-Ms both engulf glioblastoma cells and block glioblastoma invasive behavior.

cancer biology↗

Comprehensive analysis of TEAD inhibition in meningioma identifies MEK and mTOR inhibition as effective combination therapies against resistant lines.

Meningiomas are the most common primary central nervous system tumors in adults, posing a significant burden to society. Although a large percentage of lower-grade meningiomas are curable by surgery or radiation alone, high-grade and a subset of low-grade meningiomas demonstrate recurrences and complications from treatment. Systemic therapies for meningioma remain ineffective, and no targeted treatments are approved. Despite the central role of YAP1/TAZ-TEAD signaling in NF2-deficient/mutant tumors, no studies have systematically examined TEAD inhibition across molecularly defined meningioma subtypes or investigated mechanisms of resistance in this disease. We have recently shown that YAP1/TAZ signaling is an oncogenic driver of meningioma. Here, using established and patient-derived meningioma cell lines, we demonstrate that genetic ablation of YAP1/TAZ suppresses growth in both NF2 mutant and NF2 wild type cell lines, establishing YAP1/TAZ-TEAD signaling as a shared oncogenic dependency. Pharmacologic TEAD inhibition suppressed growth of benign NF2 mutant and a subset of higher-grade NF2 mutant meningiomas, whereas NF2 wild type meningiomas were generally more resistant. RNA-Seq and Western Blot analysis identified compensatory activation of MEK-ERK, mTOR-S6, and FAK signaling in resistant lines exhibit. Importantly, co-targeting these pathways was able to overcome resistance to TEADi and was superior to MEK/mTOR/FAK inhibition alone. These studies provide a compelling proof-of-concept that TEADi represents a novel therapeutic vulnerability in meningioma and reveal adaptive signaling responses that can be therapeutically exploited.

cancer biology↗

Transcriptional changes consistent with impaired neuronal differentiation, angiogenesis, and tumor plasticity induced in human subpallial telencephalic organoid-glioblastoma chimeras.

Glioblastoma multiforme (GBM) is one of the most aggressive and therapy-resistant brain tumors prevalent in both adults and children. Despite extensive research to understand GBM pathology, it remains unclear how neural cells in the human brain interact with GBM cells to support their brain propagation and therapy resistance and whether GBM cells exert any influence on the properties of human neural cells. In this study, we co-culture human stem cell-derived subpallial telencephalic organoids with patient-derived proneural or mesenchymal GBM spheroids to investigate their reciprocal interactions. We show that both proneural and mesenchymal GBM spheroids readily fuse and propagate with human organoids, forming organoid-GBM chimeras, without the need for exogenous growth factors. GBM cells within the chimeras adapt by modulating gene expression profiles consistent with diminished proliferation, heightened hypoxia, increased angiogenesis, and proneural-to-mesenchymal transition in proneural GBM. Both proneural or mesenchymal GBMs also exert an impact on the properties of neural cells in the chimeras, leading to the suppression of neuronal genes and an upregulation expression of genes associated with hypoxia and angiogenesis. Collectively, this study identifies specific genes and molecular pathways that can be altered in GBM and neural cells by reciprocal interactions in a human developing brain-like environment for an increased understanding of GBM pathology and future therapy development.

cancer biology↗

Loss of the endocytic tumor suppressor HD-PTP phenocopies LKB1 and promotes RAS-driven oncogenesis.

Abstract/SummaryOncogenic RAS mutations drive aggressive cancers that are difficult to treat in the clinic, and while direct inhibition of the most common KRAS variant in lung adenocarcinoma (G12C) is undergoing clinical evaluation, a wide spectrum of oncogenic RAS variants together make up a large percentage of untargetable lung and GI cancers. Here we report that loss-of-function alterations (mutations and deep deletions) in the gene that encodes HD-PTP (PTPN23) occur in up to 14% of lung cancers in the ORIEN Avatar lung cancer cohort, associate with adenosquamous histology, and occur alongside an altered spectrum of KRAS alleles. Furthermore, we show that in publicly available early-stage NSCLC studies loss of HD-PTP is mutually exclusive with loss of LKB1, which suggests they restrict a common oncogenic pathway in early lung tumorigenesis. In support of this, knockdown of HD-PTP in RAS-transformed lung cancer cells is sufficient to promote FAK-dependent invasion. Lastly, knockdown of the Drosophila homolog of HD-PTP (dHD-PTP/Myopic) synergizes to promote RAS-dependent neoplastic progression. Our findings highlight a novel tumor suppressor that can restrict RAS-driven lung cancer oncogenesis and identify a targetable pathway for personalized therapeutic approaches for adenosquamous lung cancer.

cancer biology↗

Replicative Instability Drives Cancer Progression

In the past decade, defective DNA repair has been increasingly linked with cancer progression. Human tumors with markers of defective DNA repair and increased replication stress have been shown to exhibit genomic instability and poor survival rates across tumor types. Here we utilize-omics data from two independent consortia to identify the genetic underpinnings of replication stress, therapy resistance, and primary carcinoma to brain metastasis in BRCA wildtype tumors. In doing so, we have defined a new pan-cancer class of tumors characterized by replicative instability (RIN). RIN is defined by genomic evolution secondary to replicative challenge. Our data supports a model whereby defective single-strand break repair, translesion synthesis, and non-homologous end joining effectors drive RIN. Collectively, we find that RIN accelerates cancer progression by driving copy number alterations and transcriptional program rewiring that promote tumor evolution. Statement of SignificanceDefining the genetic basis of genomic instability with wildtype BRCA repair effectors is a significant unmet need in cancer research. Here we identify and characterize a pan-cancer cohort of tumors driven by replicative instability (RIN). We find that RIN drives therapy resistance and distant metastases across multiple tumor types.

cancer biology↗