Turley, Tamiel N.

Abstract Gastrointestinal (GI) cancers are rising in people < 50 and remain major causes of cancer mortality despite therapeutic advances. Chimeric antigen receptor T (CART) cell therapy has transformed treatment of hematological cancers. However, its efficacy in GI cancers has been hindered by antigen heterogeneity and immunosuppressive cancer associated fibroblasts (CAFs) in the tumor microenvironment (TME.) Here we aimed to 1) study CART-CAF interactions and 2) engineer CART cells capable of eliminating CAFs to overcome their inhibitory role and enhance their antitumor activity in GI cancers. We first analyzed primary CAFs from 20 GI cancer patients. CAFs showed high fibroblast activation protein (FAP) expression and significantly suppressed T cells proliferation (26-77%, p≤0.0001). We next generated CART cells capable of safely eliminating both GI cancer cells and CAFs. To target cancer cells, we developed a novel nanobody (VHH)-based CAR against Claudin18.2, a GI cancer specific target. To avoid off-tumor toxicity in healthy FAP+ tissues, we incorporated an inducible FAP-CAR using the synNotch platform, enabling conditional targeting upon engagement with Claudin18.2+ cells, restricting FAP targeting within the TME. VHH Claudin18.2 CART cells showed superior specificity and efficacy vs scFv-based CART cells (hu8E85 or zolbetuximab). In Claudin18.2+ SNU-C2B xenografts, tumors were 92mm3 (VHH) vs 48mm3 (huE85) vs 211mm3 (zolbetuximab) on day 23 post-CART, median survival undefined vs 17 days vs 23 days respectively; p=0005. In Claudin18.2+ LS411N xenografts, tumors were 315mm3 vs 106mm3 vs 382 mm3 respectively at 23 days post-CART, median survival undefined vs 19 days vs undefined respectively; p=0004. VHH Claudin18.2 CART cells showed no off-tumor effects, while hu8E85 CART induced significant toxicity. We next established a co-engraftment model. NSG mice received 1x106 SNU-C2B and 6x106 CAFs from a GI cancer patient. At 500 mm3 tumors, mice received 5x106 VHH Claudin18.2 or inducible Claudin18.2/FAP CART. Dual-targeting CART cells showed greater antitumor response (728mm3 vs 320mm3, p=0.0011 at day 20 post-CART), expansion (61 vs 2,350 CART/µl of blood, p=0.0037), and tumor infiltration (8.71 x 105 vs 1.03 x 106 CART/g of tumor, p<0.0001). This was also observed in gastric, colon, and pancreatic PDX models, with no observable off-tumor cytotoxic effects with inducible dual-targeting Claudin18.2/FAP CART. Our findings demonstrate that our novel VHH-based Claudin18.2 CART cells are highly specific and effective against GI malignancies, and that inducible Claudin18.2/FAP dual-targeting CART cells safely remodel the TME into an immune-permissive state. This approach represents a mechanistically innovative and translationally relevant strategy to overcome CAF-mediated immunosuppression, enhance CART cell efficacy, and improve clinical outcomes in refractory solid tumors. Citation Format: Omar L. Gutierrez Ruiz, Jennifer Feigin, Brooke Kimball, R. Leo Sakemura, Elizabeth L. Siegler, Dominic A. Skeele, Ateka Saleh, Claudia Manriquez Roman, Ismail Can, Olivia Sirpilla, Kun Yun, Carli M. Stewart, Mehrdad Hefazi, Yoh Yamaguchi, Lionel Aurelien Kankeu Fonkoua, Long K. Mai, Truc Huynh, Sophia Y. Goldberg, Grace E. DeFranco, Sara Foote, Ekene Johnkennedy Newton Ogbodo, Hong Xia, Michael Redig, Matthew L. Matthew, Tamiel Nichole Turley, Skyeler Klinge, John Alton Copland, Saad J. Kenderian. Optimized CART cell therapy to remodel the tumor microenvironment and eliminate GI malignancies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 1525.

Abstract Lipid metabolism plays an important role in lung cancer growth, survival, and therapeutic resistance. Stearoyl-CoA desaturase 1 (SCD1), the enzyme that converts saturated fatty acids (SFAs) into monounsaturated fatty acids (MUFAs), represents a metabolic vulnerability since cancer cells depend on MUFAs for membrane biosynthesis, ER homeostasis, and alternative energy to glucose. SSI-4 (a.k.a MTI-301) is a selective SCD1 inhibitor currently in Phase I clinical evaluation for metastatic, unresectable, or refractory solid cancers, but its activity in non-small cell lung cancer (NSCLC) has not yet been characterized. To evaluate how NSCLC models respond to SCD1 blockade, we performed an initial screen of a panel of 17 human non-small cell lung cancer cell lines treated with 100 nM SSI-4 under defined serum conditions. Cell viability assays identified 9 responding cell lines, and dose-response studies confirmed IC50 values ranging from approximately 0.65 to 45.5 nM. Rescue experiments showed that adding oleic acid, an SCD1 regulated MUFA, reversed SSI-4-mediated growth inhibition, confirming mechanistically that this effect occurs through SCD1 blockade. Western blot analysis confirmed that SSI-4 treatment increased markers of endoplasmic reticulum (ER) stress and apoptosis in sensitive lines, consistent with disruption of lipid homeostasis. In contrast, non-responsive lines exhibited minimal induction of these stress pathways and retained viability despite treatment. Soft agar assays further showed that SSI-4 reduced anchorage-independent colony formation in responsive lines, indicating that SCD1 inhibition suppresses a key malignant growth property in these NSCLC models. Collectively, these findings demonstrate that SSI-4 selectively inhibits proliferation in a subset of NSCLC cells through an SCD1-dependent mechanism by reducing MUFA availability and activating stress and apoptotic signaling. This work establishes a framework for subsequent in vivo studies and lays the foundation for exploring SCD1 inhibition as a potential therapeutic strategy for patients with limited treatment options in NSCLC, while also advancing understanding of the mechanisms by which SCD1 supports tumor survival. Citation Format: Valeria Romina Salerno Gonzales, Lauren Antal, Tamiel Nichole Turley, John A. Copland III. Inhibition of stearoyl-CoA desaturase 1 (SCD1) by SSI-4 as a therapeutic strategy in non-small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 2942.

Triple-negative breast cancer (TNBC) remains highly aggressive and refractory to conventional treatments, underscoring the need for novel combination strategies. Here, we employed 2D and 3D in vitro models, transcriptomic profiling, and in vivo xenograft studies to evaluate the anticancer efficacy of cannabinoids combined with the terpene β-caryophyllene (BC) in resistant TNBC models. Among the tested cannabinoids, cannabichromene (CBC) exhibited the greatest potency, and its combination with BC at sub-toxic concentrations significantly reduced IC50 values, enhanced cytotoxicity in spheroids, and suppressed colony formation and migration. The combination treatment induced pronounced G1 cell cycle arrest and increased apoptotic cell death. Western blot analyses revealed downregulation of PARP, Survivin, mTOR, Vimentin, Glypican-5, and PD-L1, while RNA sequencing demonstrated suppression of proliferative and migratory signaling pathways alongside activation of apoptosis, autophagy, and ferroptosis-related pathways. In vivo, CBC + BC significantly inhibited tumor growth in MDA-MB-231 xenografts, outperforming single-agent treatments. Collectively, these findings demonstrate that BC synergistically enhances cannabinoid activity, yielding superior antiproliferative and anti-migratory effects, and highlight this combination as a promising therapeutic strategy for resistant TNBC.

Rare familial spontaneous coronary artery dissection (SCAD) kindreds implicate genetic disease predisposition and provide a unique opportunity for candidate gene discovery. Whole-genome sequencing was performed in fifteen probands with non-syndromic SCAD who had a relative with SCAD, eight of whom had a second relative with extra-coronary arteriopathy. Co-segregating variants and associated genes were prioritized by quantitative variant, gene, and disease-level metrics. Curated public databases were queried for functional relationships among encoded proteins. Fifty-four heterozygous coding variants in thirteen families co-segregated with disease and fulfilled primary filters of rarity, gene variation constraint, and predicted-deleterious protein effect. Secondary filters yielded 11 prioritized candidate genes in 12 families, with high arterial tissue expression (n = 7), high-confidence protein-level interactions with genes associated with SCAD previously (n = 10), and/or previous associations with connective tissue disorders and aortopathies (n = 3) or other vascular phenotypes in mice or humans (n = 11). High-confidence associations were identified among 10 familial SCAD candidate-gene-encoded proteins. A collagen-encoding gene was identified in five families, two with distinct variants in COL4A2. Familial SCAD is genetically heterogeneous, yet perturbations of extracellular matrix, cytoskeletal, and cell–cell adhesion proteins implicate common disease-susceptibility pathways. Incomplete penetrance and variable expression suggest genetic or environmental modifiers.

Introduction: Spontaneous coronary artery dissection (SCAD) is an understudied cause of acute myocardial infarction due to hematoma formation in coronary arteries primarily affecting women. It is not known to what extent SCAD is genetically distinct from other cardiovascular diseases, including atherosclerotic coronary artery disease (CAD). Methods and Results: Through a meta-analysis of 8 GWAS (1917 cases, 9292 controls of European ancestry), we identified 17 risk loci, including 12 new. Functional annotations pointed at enrichment in enhancer marks of arteries, specifically smooth muscle cells, and strong candidate genes, such as tissue factor gene ( F3 ) on Chr1 near rs1146473 (OR=1.32, P=5.8 х10 -9 ). F3 is novel for SCAD or any cardiovascular disease. The risk allele correlated with F3 lower expression in arteries, supporting a mechanism consistent with hematoma formation. Bayesian gene regulatory networks constructed from expression and genetics data indicated the extracellular matrix organization in arteries as the biological function where most prioritized genes clustered (e.g. COL4A1/A2, HTRA1, and TIMP3 ). Overall, we report substantial polygenicity for SCAD (LDSC: h 2 SNP = 0.71 ± 0.11) and shared genetics with several neurovascular diseases (e.g intracranial aneurysm). Intriguingly, for 6 loci, colocalization analyses showed that SCAD and CAD are likely to share the same causal variants but involve opposite risk alleles (e.g COL4A1/A2 ). In addition, a negative genetic correlation was found between SCAD and CAD (rg=-0.12; P=3.7х10 -3 ), including after conditioning on BP (mt-COJO: rg CAD/SBP =-0.19, P=4.6х10 -6 ). Mendelian randomization analyses indicated higher BP to associate with increased risk for SCAD (beta IVW-SBP =0.05, P=7.6х10 -6 , beta IVW-DBP =0.10, P=1.9х10 -6 ) and CAD (beta IVW-SBP =0.04, P=8.6х10 -49 ; DBP: beta IVW-DBP =0.06, P=1.6х10 -44 ) but not BMI, lipids, or type 2 diabetes, which we confirmed as genetic risk factors for CAD Conclusions: Our results set the stage for future investigation of novel biological pathways relevant to both SCAD and CAD and potential therapeutic and preventive strategies specifically targeting this ischemic disease predominantly affecting women.

Background: Spontaneous coronary artery dissection (SCAD) is an uncommon idiopathic disorder predominantly affecting young, otherwise healthy women. Rare familial cases reveal a genetic predisposition to disease. The aim of this study was to identify a novel susceptibility gene for SCAD. Methods: Whole-exome sequencing was performed in a family comprised of 3 affected individuals and filtered to identify rare, predicted deleterious, segregating variants. Immunohistochemical staining was used to evaluate protein expression of the identified candidate gene. The prevalence and spectrum of rare (<0.1%) variants within binding domains was determined by next-generation sequencing or denaturing high-performance liquid chromatography in a sporadic SCAD cohort of 675 unrelated individuals. Results: We identified a rare heterozygous missense variant within a highly conserved β-integrin–binding domain of TLN1 segregating with familial SCAD. TLN1 encodes talin 1—a large cytoplasmic protein of the integrin adhesion complex that links the actin cytoskeleton and extracellular matrix. Consistent with high mRNA expression in arterial tissues, robust immunohistochemical staining of talin 1 was demonstrated in coronary arteries. Nine additional rare heterozygous missense variants in TLN1 were identified in 10 sporadic cases. Incomplete penetrance, suggesting genetic or environmental modifiers of this episodic disorder, was evident in the familial case and 5 individuals with sporadic SCAD from whom parental DNA was available. Conclusions: Our findings reveal TLN1 as a disease-associated gene in familial and sporadic SCAD and, together with abnormal vascular phenotypes reported in animal models of talin 1 disruption, implicate impaired structural integrity of the coronary artery cytoskeleton in SCAD susceptibility.