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Hata, A. N.

Publications and source records attributed to Hata, A. N..

16 recordsLinked to original sources

Tyrosine phosphorylation and dimerization cooperatively activate NAMPT to enable NAD+ synthesis in cancer

Nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme in the NAD salvage pathway, is frequently upregulated in cancer, yet mechanisms regulating its catalytic activity remain undefined. We identify NAMPT as a direct substrate of multiple proto-oncogenic tyrosine kinases, including ALK, insulin receptor, IGF1R, and PDGFRA. Phosphoproteomics identified NAMPT Y188 as the major phosphorylation site, including the oncogenic fusion kinase NPM1::ALK. NAMPT interacted with NPM1::ALK in the cytoplasm, nucleus, and mitochondria, while Y188 phosphorylation enhanced catalytic activity, NMN/NAD biosynthesis, and downstream metabolism. Conversely, the Y188F mutant reduced enzymatic activity, proliferation, and clonogenicity, whereas disrupting dimerization similarly impaired phosphorylation and function. Interactome analyses showed phosphorylation and dimerization cooperatively remodel NAMPT-associated networks, enriching phosphorylated dimers for metabolic/redox regulators and monomeric NAMPT for ribosome biogenesis. NAMPT inhibition suppressed the growth of both ALK inhibitor-sensitive and -resistant lymphoma cells and enhanced the efficacy of ALK inhibition, revealing kinase-dependent NAMPT activation as a metabolic vulnerability in oncogene-driven cancers.

cancer biology↗

Dual inhibition of GTP-bound (ON) and GDP-bound (OFF) KRASG12C suppresses PI3Kα and leads to potent tumor inhibition

Current approved KRASG12C inhibitors covalently bind the inactive GDP-bound (OFF) form of KRASG12C. Recently, KRASG12C inhibitors that selectively bind to the GTP-bound (ON) form of both KRASG12C (ON) and (OFF) forms have been reported and entered clinical testing. In principle, KRASG12C (ON) inhibitors may be less susceptible to adaptive mechanisms that promote resistance to (OFF) inhibitors, however the specific mechanisms that differentiate the activity of (ON) versus (OFF) inhibition are not well understood. We profiled the activity of BBO-8520, a covalent dual inhibitor of GTP-bound (ON) and GDP-bound (OFF) KRASG12C, in KRASG12C-mutant non-small cell lung cancer models. BBO-8520 exerted more potent and sustained inhibition of KRASG12C and anti-tumor activity in vitro and in vivo compared with sotorasib, a KRASG12C (OFF)-only inhibitor. While cells treated with BBO-8520 or sotorasib both exhibited feedback reactivation of MAPK signaling driven by wild-type HRAS/NRAS isoforms, more durable suppression of KRASG12C by BBO-8520 was associated with decreased PI3K-AKT activation in vitro. Disruption of the interaction between RAS and PI3K using a novel protein:protein interaction inhibitor suppressed PI3K-AKT activation and increased the tumor response to sotorasib to a similar level as BBO-8520. Moreover, in some contexts, disruption of RAS-PI3K further increased the anti-tumor activity of BBO-8520 monotherapy. These results reveal mechanistic differences between KRAS (ON) and (OFF) inhibitors, highlight the importance of PI3K-AKT signaling in driving resistance to KRAS inhibition in lung cancer, and suggest combination strategies that suppress PI3K-AKT to improve the response to KRAS inhibitors.

cancer biology↗

ApoFLARE: a luminescent reporter for direct quantification of APOBEC3A editing activity

APOBEC-mediated cytidine deamination is a major endogenous source of mutagenesis in human cancers and has been linked to tumor evolution, clonal diversification and therapeutic resistance. Among the APOBEC family, APOBEC3A (A3A) is a potent and inducible cytidine deaminase, with dynamic and context-dependent activation. Most approaches for studying the role of A3A in cancer infer A3A activity indirectly via its expression level or retrospective mutational signatures, or through molecular assays that are limited to endpoint measurements and do not readily allow longitudinal interrogation of A3A editing dynamics. Therefore, quantifying the timing, persistence, and cellular heterogeneity of A3A activity remains challenging. Here, we describe ApoFLARE, a genetically encoded reporter that converts A3A-mediated cytidine deamination into a quantitative luminescent signal in living cells. ApoFLARE allows for scalable, ratiometric measurement of editing activity and enables time-resolved analysis of editing kinetics. Reporter activation is selectively dependent on A3A catalytic function and was absent in A3A-deficient, but not A3B-deficient cells. Under stress and targeted therapy conditions, reporter activity correlated with endogenous RNA editing measured by digital droplet PCR, including contexts in which catalytic activity persisted beyond transient A3A transcript induction. Thus, ApoFLARE offers a scalable platform to investigate the regulation, kinetics, and heterogeneity of A3A editing. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=154 SRC="FIGDIR/small/710312v1_ufig1.gif" ALT="Figure 1"> View larger version (39K): org.highwire.dtl.DTLVardef@19497aborg.highwire.dtl.DTLVardef@71866borg.highwire.dtl.DTLVardef@12ffbdaorg.highwire.dtl.DTLVardef@13fd501_HPS_FORMAT_FIGEXP M_FIG C_FIG

molecular biology↗

Prevalence and Actionability of MTAP Loss in Oncogene-Driven Lung Cancer

BackgroundMethylthioadenosine phosphorylase (MTAP) loss co-occurs with actionable genomic alterations in non-small cell lung cancer (NSCLC) and creates vulnerability to protein arginine methyltransferase 5 (PRMT5) inhibition. Estimates of prevalence of MTAP loss rely on next-generation sequencing which can underestimate copy losses. Moreover, the activity of PRMT5 inhibitors in oncogene-driven NSCLC is not well established. MethodsWe assessed MTAP expression by immunohistochemistry (IHC) in 243 NSCLCs (n=132 early stage, n=111 metastatic), including 33 specimens with paired lymph nodes. Antiproliferative activity of PRMT5 inhibitor monotherapy and in combination with tyrosine kinase inhibitors (TKIs) was evaluated in MTAP-deleted NSCLC cell lines harboring EGFR or KRAS mutations or ALK rearrangements. ResultsAmong 243 NSCLC specimens from 240 patients (72% with driver alterations, 90% adenocarcinoma), MTAP loss was identified in 43 (18%) specimens from 40 (17%) patients, including 18 (14%) early-stage and 22 (20%) metastatic tumors. MTAP loss occurred in 24% of stage 4 driver-positive NSCLCs versus 14% of driver-negative tumors (p=0.314). Twenty (61%) lung-nodal pairs demonstrated concordance; eight cases only exhibited decreased MTAP expression in nodes. Variable sensitivity to PRMT5 inhibitors was observed in 22 MTAP-deleted NSCLC cell lines (9 EGFR-mutant, 7 KRAS-mutant, 6 ALK-rearranged), with responses seen in TKI-sensitive and TKI-resistant lines. SDMA (symmetric dimethylarginine) expression did not predict PRMT5 inhibitor sensitivity. TKI + PRMT5 inhibitor combos had greater activity than monotherapy. ConclusionsMTAP loss occurs in 1-in-5 oncogene-driven metastatic NSCLCs. PRMT5 inhibitor activity is independent of TKI exposure, driver alteration, and SDMA expression and enhanced by addition of TKI. These findings support clinical evaluation of PRMT5 inhibitor + TKI combinations for advanced NSCLC.

cancer biology↗

Targeted therapy-induced chromosomal instability dictates mitotic dependency on Aurora Kinase A

Targeted therapies eliminate cancer cells by inhibiting oncogenic signaling; however, tumor cells often evade cytotoxicity through proteomic and epigenetic reprogramming that enables survival. These adaptive responses may create collateral cellular stresses, such as DNA damage, that can be therapeutically exploited. When unresolved, DNA damage leads to chromosomal instability (CIN), a potential source of vulnerability. Whether KRAS inhibition induces DNA damage or CIN in KRAS-mutant non-small cell lung cancer (NSCLC) has not been established. Here, we show that the KRASG12C inhibitor LY3499446 induces CIN in KRAS-mutant NSCLC cell lines. A targeted compound screen revealed that the extent of CIN induction by KRASG12C inhibition strongly correlates with therapeutic synergy with the selective Aurora kinase A inhibitor LSN3321213. Mechanistically, KRASG12C inhibition stabilizes cyclin B1 during mitosis through activation of mitotic ATR/ATM signaling. In the presence of Aurora Kinase A inhibition, cyclin B1 stabilization delays mitotic exit and diverts cell fate from mitotic slippage or division toward mitotic catastrophe. Together, our findings identify CIN as a predictive marker of response to combined KRASG12C and Aurora Kinase A inhibition, providing mechanistic rationale to enhance the therapeutic window of AURKA inhibitors when used with targeted therapies.

cancer biology↗

M1C is a druggable target for NSCLC KRAS G12C mutant tumors resistant to KRAS inhibitors

Treatment of NSCLC KRAS G12C mutant tumors with the allele-selective sotorasib inhibitor is invariably associated with acquired resistance. The MUC1-encoded oncogenic M1C protein is necessary for self-renewal of NSCLC KRAS mutant cells. We report that treatment of NSCLC KRAS G12C cells with sotorasib induces M1C expression by a STAT1-dependent pathway. In turn, M1C drives sotorasib resistance by NF-{kappa}B-mediated induction of the epithelial-mesenchymal transition (EMT). Targeting M1C(R)NF-{kappa}B signaling (i) suppresses EMT, and (ii) reverses sotorasib resistance. Of translational relevance, treatment with a M1C antibody-drug conjugate (ADC) is effective against sotorasib-resistant NSCLC KRAS G12C cell line and patient-derived tumor xenografts. Clinically, targeted treatment of patients with NSCLC KRAS G12C tumors overexpressing MUC1 associates with decreases in overall survival. These findings identify M1C as a key effector of sotorasib resistance and as a target for treatment of patients with refractory NSCLC KRAS G12C mutant tumors.

cancer biology↗

Unprocessed Genomic Uracil as a Source of DNA Replication Stress in Cancer Cells

Alterations of bases in DNA constitute a major source of genomic instability. It is believed that base alterations trigger base excision repair (BER), generating DNA repair intermediates interfering with DNA replication. Here, we show that genomic uracil, a common base alteration, induces DNA replication stress (RS) without being processed by BER. In the absence of uracil DNA glycosylase (UNG), genomic uracil accumulates to high levels, DNA replication forks slow down, and PrimPol-mediated repriming is enhanced, generating single-stranded gaps in nascent DNA. ATR inhibition in UNG-deficient cells blocks repair of uracil-induced gaps, increasing replication fork collapse and cell death. Notably, a subset of cancer cells harboring high levels of genomic uracil upregulate UNG2 to limit RS, and these cancer cells are hypersensitive to co-treatment with ATR inhibitors and drugs increasing genomic uracil. These results reveal unprocessed genomic uracil as an unexpected source of RS and a targetable vulnerability of cancer cells.

molecular biology↗

A cellular and spatial atlas of TP53-associated tissue remodeling in lung adenocarcinoma

TP53 is the most frequently mutated gene across many cancers and is associated with shorter survival in lung adenocarcinoma (LUAD). To define how TP53 mutations affect the LUAD tumor microenvironment (TME), we constructed a multi-omic cellular and spatial tumor atlas of 23 treatment-naive human lung tumors. We found that TP53-mutant (TP53mut) malignant cells lose alveolar identity and upregulate highly proliferative and entropic gene expression programs consistently across resectable LUAD patient tumors, genetically engineered mouse models, and cell lines harboring a wide spectrum of TP53 mutations. We further identified a multicellular tumor niche composed of SPP1+ macrophages and collagen-expressing fibroblasts that coincides with hypoxic, pro-metastatic expression programs in TP53mut tumors. Spatially correlated angiostatic and immune checkpoint interactions, including CD274-PDCD1 and PVR-TIGIT, are also enriched in TP53mut LUAD tumors, which may influence response to checkpoint blockade therapy. Our methodology can be further applied to investigate mutation-specific TME changes in other cancers.

cancer biology↗

Targeted therapies prime oncogene-driven lung cancers for macrophage-mediated destruction

Macrophage immune checkpoint inhibitors, such as anti-CD47 antibodies, show promise in clinical trials for solid and hematologic malignancies. However, the best strategies to use these therapies remain unknown and ongoing studies suggest they may be most effective when used in combination with other anticancer agents. Here, we developed a novel screening platform to identify drugs that render lung cancer cells more vulnerable to macrophage attack, and we identified therapeutic synergy exists between genotype-directed therapies and anti-CD47 antibodies. In validation studies, we found the combination of genotype-directed therapies and CD47 blockade elicited robust phagocytosis and eliminated persister cells in vitro and maximized anti-tumor responses in vivo. Importantly, these findings broadly applied to lung cancers with various RTK/MAPK pathway alterations--including EGFR mutations, ALK fusions, or KRASG12C mutations. We observed downregulation of {beta}2-microglobulin and CD73 as molecular mechanisms contributing to enhanced sensitivity to macrophage attack. Our findings demonstrate that dual inhibition of the RTK/MAPK pathway and the CD47/SIRPa axis is a promising immunotherapeutic strategy. Our study provides strong rationale for testing this therapeutic combination in patients with lung cancers bearing driver mutations. Brief summaryUnbiased drug screens identify targeted therapies as drugs that make lung cancers with driver mutations more vulnerable to macrophage attack.

cancer biology↗

LKB1 loss rewires JNK-induced apoptotic protein dynamics through NUAKs and sensitizes KRAS-mutant NSCLC to combined KRASG12C + MCL-1 blockade

The efficacy of molecularly targeted anti-cancer therapies may be limited by the presence of co-occurring mutations within a tumor1-3. Conversely, these alterations may confer collateral vulnerabilities that can be leveraged for the development of novel therapeutic approaches. KRAS-mutant lung cancers are distinguished by recurrent inactivating mutations in the tumor suppressor STK11/LKB14 that facilitate tumorigenesis by modulating energy balance5, 6, enhancing metastatic potential7,8 and enabling immune evasion9,10. However, whether LKB1 plays a role in modulating cellular responses to therapeutic stress is largely unknown. Here we show that LKB1 suppresses JNK-dependent stress signaling in KRAS-mutant lung cancer cells upon acute loss of oncogenic signaling. In LKB1-deficient KRAS-mutant cells, inhibition of KRAS or its downstream effector MEK leads to hyperactivation of JNK due to loss of NUAK-mediated PP1B phosphatase activity. JNK-mediated inhibitory phosphorylation of BCL-XL rewires apoptotic dependencies, rendering LKB1-deficient cells vulnerable to MCL-1 inhibition. These results uncover a previously unknown role for LKB1 in regulating stress signaling and the mitochondrial apoptotic response of cancer cells independent of its tumor suppressor activity mediated by AMPK11-13 and SIK14,15 kinases. Additionally, our study reveals a therapy-induced vulnerability in LKB1-deficient KRAS-mutant lung cancer cells that could be exploited as a genotype-informed strategy to improve the efficacy of KRAS-targeted therapies.

cancer biology↗

NRF2 activation induces NADH-reductive stress providing a metabolic vulnerability in lung cancer

Multiple cancers regulate oxidative stress by activating the transcription factor NRF2 through mutation of its negative regulator KEAP1. NRF2 has been studied extensively in KEAP1-mutant cancers, however the role of this pathway in cancers with wildtype KEAP1 remains poorly understood. To answer this question, we induced NRF2 via pharmacological inactivation of KEAP1 in a panel of 50+ non-small lung cancer cell lines. Unexpectedly, marked decreases in viability were observed in >13% of the cell lines--an effect that was completely rescued by NRF2 ablation. Genome-wide and targeted CRISPR screens revealed that NRF2 induces NADH-reductive stress, through the upregulation of the NAD+-consuming enzyme ALDH3A1. Leveraging these findings, we show that cells treated with KEAP1 inhibitors or those with endogenous KEAP1 mutations are selectively vulnerable to Complex I inhibition, which impairs NADH oxidation capacity and potentiates reductive stress. Thus, we identify reductive stress as a metabolic vulnerability in NRF2-activated lung cancers.

molecular biology↗

Stitchr: stitching coding TCR nucleotide sequences from V/J/CDR3 information

The study and manipulation of T cell receptors (TCRs) is central to multiple fields across basic and translational immunology research. Produced by V(D)J recombination, TCRs are often only recorded in the literature and data repositories as a combination of their V and J gene symbols, plus their hypervariable CDR3 amino acid sequence. However, numerous applications require full-length coding nucleotide sequences. Here we present Stitchr, a software tool developed to specifically address this limitation. Given minimal V/J/CDR3 information, Stitchr produces complete coding sequences representing a fully spliced TCR cDNA. Due to its modular design, Stitchr can be used for TCR engineering using either published germline or novel/modified variable and constant region sequences. Sequences produced by Stitchr were validated by synthesizing and transducing TCR sequences into Jurkat cells, recapitulating the expected antigen specificity of the parental TCR. Using a companion script, Thimble, we demonstrate that Stitchr can process a million TCRs in under ten minutes using a standard desktop personal computer. By systemizing the production and modification of TCR sequences, we propose that Stitchr will increase the speed, repeatability, and reproducibility of TCR research. Stitchr is available on GitHub.

immunology↗

Structural and functional analysis of lorlatinib analogs reveals roadmap for targeting diverse compound resistance mutations in ALK-positive lung cancer

The treatment approach to advanced, ALK-positive non-small cell lung cancer (NSCLC) utilizing sequential ALK tyrosine kinase inhibitors (TKIs) represents a paradigm of precision oncology. Lorlatinib is currently the most advanced, potent and selective ALK tyrosine kinase inhibitor (TKI) in the clinic. However, tumors invariably acquire resistance to lorlatinib, and after sequential ALK TKIs culminating with lorlatinib, diverse refractory compound ALK mutations can emerge. Here, we determine the spectrum of lorlatinib-resistant compound ALK mutations identified in patients after treatment with lorlatinib, the majority of which involve ALK G1202R or I1171N/S/T. By assessing a panel of lorlatinib analogs against compound ALK mutant in vitro and in vivo models, we identify structurally diverse lorlatinib analogs that harbor differential selective profiles against G1202R- versus I1171N/S/T-based compound ALK mutations. Structural analysis revealed that increased potency against compound mutations was achieved primarily through two different mechanisms of improved targeting of either G1202R- or I1171N/S/T-mutant kinases. Based on these results, we propose a classification of heterogenous ALK compound mutations designed to focus the development of distinct therapeutic strategies for precision targeting of compound resistance mutations following sequential TKIs.

cancer biology↗

APOBEC3A drives acquired resistance to targeted therapies in non-small cell lung cancer

Acquired drug resistance to even the most effective anti-cancer targeted therapies remains an unsolved clinical problem. Although many drivers of acquired drug resistance have been identified1-6, the underlying molecular mechanisms shaping tumor evolution during treatment are incompletely understood. The extent to which therapy actively drives tumor evolution by promoting mutagenic processes7 or simply provides the selective pressure necessary for the outgrowth of drug-resistant clones8 remains an open question. Here, we report that lung cancer targeted therapies commonly used in the clinic induce the expression of cytidine deaminase APOBEC3A (A3A), leading to sustained mutagenesis in drug-tolerant cancer cells persisting during therapy. Induction of A3A facilitated the formation of double-strand DNA breaks (DSBs) in cycling drug-treated cells, and fully resistant clones that evolved from drug-tolerant intermediates exhibited an elevated burden of chromosomal aberrations such as copy number alterations and structural variations. Preventing therapy-induced A3A mutagenesis either by gene deletion or RNAi-mediated suppression delayed the emergence of drug resistance. Finally, we observed accumulation of A3A mutations in lung cancer patients who developed drug resistance after treatment with sequential targeted therapies. These data suggest that induction of A3A mutagenesis in response to targeted therapy treatment may facilitate the development of acquired resistance in non-small-cell lung cancer. Thus, suppressing expression or enzymatic activity of A3A may represent a potential therapeutic strategy to prevent or delay acquired resistance to lung cancer targeted therapy.

cancer biology↗

Modeling Resistance and Recurrence Patterns of Combined Targeted- Chemoradiotherapy Predicts Benefit of Shorter Induction Period

The optimal integration of molecularly targeted therapies with concurrent chemotherapy and radiation (CRT) to improve cures in genotype-defined cancers is unknown. Here, we develop a bio-mathematical framework to simulate patterns of local versus distant recurrences in a heterogeneous lung cancer population receiving combined targeted therapy and CRT. Our validated model predicts that targeted induction before CRT, an approach currently being tested in clinical trials, may render adjuvant targeted therapy less effective due to proliferation of drug-resistant cancer cells when using very long induction periods. Furthermore, our simulations not only demonstrate the competing effects of drug-resistant cell expansion versus overall tumor regression as a function of induction length, but can also directly estimate the probability of observing an improvement in progression-free survival at a given cohort size. We thus demonstrate that such stochastic biological simulations have the potential to quantitatively inform the design of multimodality clinical trials in genotype-defined cancers.

biophysics↗

A single-cell and single-nucleus RNA-seq toolbox for fresh and frozen human tumors

Single cell genomics is essential to chart the complex tumor ecosystem. While single cell RNA-Seq (scRNA-Seq) profiles RNA from cells dissociated from fresh tumor tissues, single nucleus RNA-Seq (snRNA-Seq) is needed to profile frozen or hard-to-dissociate tumors. Each strategy requires modifications to fit the unique characteristics of different tissue and tumor types, posing a barrier to adoption. Here, we developed a systematic toolbox for profiling fresh and frozen clinical tumor samples using scRNA-Seq and snRNA-Seq, respectively. We tested eight tumor types of varying tissue and sample characteristics (resection, biopsy, ascites, and orthotopic patient-derived xenograft): lung cancer, metastatic breast cancer, ovarian cancer, melanoma, neuroblastoma, pediatric sarcoma, glioblastoma, pediatric high-grade glioma, and chronic lymphocytic leukemia. Analyzing 212,498 cells and nuclei from 39 clinical samples, we evaluated protocols by cell quality, recovery rate, and cellular composition. We optimized protocols for fresh tissue dissociation for different tumor types using a decision tree to account for the technical and biological variation between clinical samples. We established methods for nucleus isolation from OCT embedded and fresh-frozen tissues, with an optimization matrix varying mechanical force, buffer, and detergent. scRNA-Seq and snRNA-Seq from matched samples recovered the same cell types and intrinsic expression profiles, but at different proportions. Our work provides direct guidance across a broad range of tumors, including criteria for testing and selecting methods from the toolbox for other tumors, thus paving the way for charting tumor atlases.

genomics↗