Biology subjects

Daniels, M. A.

Publications and source records attributed to Daniels, M. A..

6 recordsLinked to original sources

bioRxiv2025

DUSP11 is an intracellular innate immune checkpoint in lung adenocarcinoma

The discovery of immune checkpoints and the rapid growth of immuno-oncology (IO) have sparked tremendous efforts to utilize the immune system to treat a wide range of cancer types/subtypes. While the major focus of IO over the past decades has been to manipulate the adaptive immune system, recent attention has been given to manipulating the innate immune system to treat cancer and/or to enhance adaptive responses. In this work we detail the intracellular protein, Dual Specificity Phosphatase 11 (DUSP11), as an innate immune checkpoint (iIC) in Non-Small Cell Lung Cancer (NSCLC) adenocarcinoma (LUAD). Expression of this atypical phosphatase is correlated with patient survival for multiple cancer types, and we show here that its activity is important for the viability of lung cancer cells in vitro. Specifically, we demonstrate that DUSP11 knockdown in LUAD cells induces apoptosis and an innate immune response capable of activating other cells in vitro, and we provide evidence that these phenotypes are primarily mediated by the pattern recognition receptor, retinoic acid inducible gene I (RIG-I). Finally, we show that expression of DUSP11 is important for tumor engraftment and growth of human LUAD in mice. Overall, these data are the first to establish DUSP11 as an immunosuppressive, pro-neoplastic, and potentially targetable protein in LUAD. In addition, our data suggests that the anti-cancer mechanisms induced by diminishing the activity of DUSP11 are likely to be generalizable to other cancer types such as breast cancer, warranting future investigation and therapeutic development.

cancer biology↗

bioRxiv2024

Anti-EGFR aptamer exhibits direct anti-cancer effects in NSCLC cells harboring EGFR L858R mutations

Non-small cell lung cancer (NSCLC) adenocarcinoma (LUAD) is a leading cause of death worldwide. Activating mutations in the tyrosine kinase domain of the oncogene epidermal growth factor receptor (EGFR) are responsible for [~]10-50% of all LUAD cases. Although EGFR tyrosine kinase inhibitors (TKIs) have been effective in prolonging NSCLC patient survival and quality of life, acquired resistance mechanisms and disease progression are inevitable. Contemporary second- and third-line treatments, such as immunotherapy, remain ineffective for these patients, presenting a clear and unmet need for alternative or adjuvant therapeutics for the treatment of mutant EGFR positive NSCLC. Here we show that an anti-EGFR aptamer (EGFRapt) decreases viability of NSCLC cell lines harboring the L858R {+/-} T790M mutation in EGFR but not cell lines harboring wild-type or exon 19 deletions. In a humanized xenograft mouse model of NSCLC, EGFRapt decreased tumor burden compared to controls when delivered intratumorally over multiple doses. To elucidate the mechanism by which EGFRapt exerts these effects, we monitored cellular processes associated with kinase-dependent and kinase-independent mechanisms and found that the anti-cancer effects of EGFRapt are cell line dependent, inhibiting cellular proliferation in one cell line and inducing cell death in another. Post hoc transcriptomics analysis supported these findings and provided additional mechanistic insights. Overall, these data establish that EGFRapt has direct anti-cancer activity in mutant EGFR positive NSCLC via targetable mechanisms that are independent of existing approaches, and they provide a foundation for further development of nucleic acid-based therapies that target EGFR.

cancer biology↗

bioRxiv2022

STING controls T cell memory fitness during infection through T cell intrinsic and IDO dependent mechanisms

Stimulator of interferon genes (STING) signaling has been extensively studied in inflammatory diseases and cancer while its role in T cell responses to infection is unclear. Using Listeria monocytogenes strains engineered to induce different levels of c-di-AMP, we found that strong STING signals impaired T cell memory upon infection via increased Bim levels and apoptosis. Unexpectedly, reduction of TCR signal strength or T cell-STING expression decreased Bim expression, T cell apoptosis and recovered T cell memory. We found that TCR signal intensity coupled STING signal strength to the Unfolded Protein Response (UPR) and T cell survival. Under strong STING signaling, IDO inhibition also reduced apoptosis and led to a recovery of T cell memory in STING sufficient CD8 T cells. Thus, STING signaling regulates CD8 T cell memory fitness through both cell-intrinsic and extrinsic mechanisms. These studies provide insight into how IDO and STING therapies could improve long-term T cell protective immunity. Significance StatementSTING signaling is an innate pathway that triggers host immunity against pathogens and cancer in response to cytosolic DNA. Additionally, STING signaling overactivation has been linked to autoimmunity. Yet, the interaction between antigenic and STING signaling and its impact in the development of protective immunity has remained unexplored. We found that strong levels of STING signaling impair CD8 T cell memory but only in response to high affinity TCR-pMHC interactions. Here, we provide evidence of how TCR signal strength controls STING signaling and IDO metabolism to regulate T cells survival as they mature to memory. These data have important implications for the design of STING and IDO combination immunotherapies

immunology↗

bioRxiv2022

IKK2/NFkB signaling controls lung resident CD8 T cell memory during influenza infection

CD8 tissue resident memory (TRM) cells are especially suited to control pathogen spread at mucosal sites. However, their maintenance in lung is limited. Here, we found that enhancing NFkB signaling in T cells once memory to influenza is established increased pro-survival Bcl-2 and CD122 levels boosting lung CD8 TRM maintenance. By contrast, enhancing NFkB signals during the contraction phase of the response led to a defect in TRM differentiation without impairing recirculating memory subsets. Specifically, inducible activation of NFkB via constitutive active IKK2 or tumor necrosis factor (TNF) interfered with tumor growth factor beta (TGF{beta}) signaling resulting in defects of lung CD8 TRM imprinting molecules CD69, CD103, Runx3 and Eomes. Conversely, inhibiting NFkB signals not only recovered but improved the transcriptional signature and generation of lung CD8 TRM. Thus, NFkB signaling is a critical regulator of tissue resident memory, whose levels can be tuned at specific times during infection to boost lung CD8 TRM.

immunology↗

bioRxiv2020

Lipidated poly(amino acid) nanostructures as versatile therapeutic delivery vehicles

Poly(amino acid)s are a diverse and capable class of polymers with significant potential for utilization in a wide variety of drug delivery applications. A sub-class of these biomaterials known as lipidated poly(amino acid)s (LPAAs) are amphiphiles composed of both hydrophobic and hydrophilic domains yielding interesting physical properties. In this article, we describe our efforts in developing a novel class of lysine and valine containing LPAAs synthesized via hexadecylamine initiated N-carboxyanhydride ring-opening polymerization (NCA-ROP). These highly hydrophobic LPAAs were found capable of undergoing hydrophobically-driven self-assembly into small nanostructures as well as being forced into larger nanostructures using a novel dump-and-stir nanoprecipitation process. This process yielded fine control over resulting nanoparticle size and cargo entrapment. Furthermore, cell-targeting DNA aptamer modification of doxorubicin-loaded LPAA nanoparticles induced significant death of co-incubated Non-Hodgkin Lymphoma cells providing exciting evidence of the therapeutic potential of this novel biomaterials-based delivery device.

bioengineering↗

bioRxiv2019

Ramified Rolling Circle Amplification for efficient and flexible synthesis of nucleosomal DNA sequences

Nucleosomes are a crucial platform for the recruitment and assembly of protein complexes that process the DNA. Mechanistic and structural in vitro studies typically rely on recombinant nucleosomes that are reconstituted using artificial, strong-positioning DNA sequences. To facilitate such studies on native, genomic nucleosomes, there is a need for methods to produce any desired DNA sequence in an efficient manner. The current methods either do not offer much flexibility in choice of sequence or are less efficient in yield and labor. Here, we show that using ramified rolling circle amplification (RCA) milligram amounts of a genomic nucleosomal DNA fragment can be produced in a scalable, one-pot reaction overnight. The ramified RCA reaction is more efficient than the existing methods, is flexible in DNA sequence and shows a 10-fold increase in yield compared to PCR, rivalling the production using plasmids. We demonstrate the method by producing the genomic DNA from the human LIN28B locus and show that it forms functional nucleosomes capable of binding pioneer transcription factor Oct4.

biochemistry↗