Cancer cells display heterogeneous pathway activity that shapes therapeutic vulnerability, but mapping it remains challenging. Transcriptomic scores do not directly measure functional activity, and CRISPR knockout data alone lack molecular interpretability. We introduce StateMap, a pathway-centric framework integrating gene expression and genome-wide CRISPR knockout fitness data from the Cancer Dependency Map. For a given pathway, StateMap selects features by co-dependency and mutual information, then projects cell lines into a low-dimensional space reflecting pathway activity and molecular state. Applied to the Hippo pathway, it resolved five functional states refining the YAP-on/YAP-off dichotomy. Notably, the 'Hippo-strong' state showed selective dependence on integrin αVβ5; ITGAV depletion triggered Hippo-dependent cell aggregation and G1 arrest via enhanced cell-cell adhesion. Machine learning transfer to TCGA identified a matching subtype with poor prognosis, nominated NNMT as a biomarker, and predicted sensitivity to the αV inhibitor Cilengitide. StateMap enables pathway-specific state mapping and discovery of state-selective therapeutic vulnerabilities.

Abstract Background: PARP inhibitors (PARPi) induce synthetic lethality in BRCA1/2-mutant (BRCA-MUT) tumors and can activate DNA-damage-linked immune pathways. The TALAVE study (NCT03964532) examined the combination of the PARPi (talazoparib) with PD-L1 blockade (avelumab). Here we evaluated spatially resolved immune signaling and remodeling in response to talazoparib alone and with avelumab. Methods: 24 patients with advanced HER2-negative breast cancer (12 BRCA-MUT, 12 BRCA-WT) received talazoparib then talazoparib + avelumab. Serial biopsies (baseline, post-PARPi [BX2], post-combination [BX3]) underwent transcriptomic, spatial protein, and multiplex IF. BRCA-dependent TME remodeling and cellular neighborhood (CN) shifts were assessed. Results: BRCA-MUT tumors showed 83% objective response and 100% clinical benefit, whereas BRCA-WT tumors exhibited minimal activity. BRCA-MUT tumors became fragmented with increased immune activity, while BRCA-WT tumors remained compact and immunosuppressed. γH2AX and pTBK1 were spatially co-expressed and sustained in BRCA-MUT tumors during treatment but declined in BRCA-WT tumors. BRCA-MUT tumors displayed enrichment of CD8+ T cells and CD163+ macrophages after PARPi, whereas CD4+ T cells and CD68+CD163+ macrophages were depleted in BRCA-WT tumors. PD-1+ CD8+ T cells were strongly linked to local CD4+ T cell density, and PD-1+ frequency in CD8+ T cells correlated with longer PFS at baseline and BX3 in BRCA-MUT but not BRCA-WT tumors.CN analysis revealed CD4+ and CD8+ enriched neighborhoods with intermediate PD-1 expression that expanded after therapy in BRCA-MUT but not BRCA-WT tumors, and these CNs lacked PD-L1+ cells. Between BX2 and BX3, BRCA-MUT tumors sustained immune activity but showed no further T cell activation or infiltration. Spatial mapping identified three PD-L1+ CN types: (1) T cell-dense niches with high PD-1/PD-L1 and γH2AX-pTBK1 activity enriched only at baseline, largely lost after PARPi; (2) macrophage-T cell mixtures that were depleted during therapy; and (3) PD-L1+ dying tumor cells lacking pTBK1 activity and T cell engagement. Across contexts, PD-L1 was either lost before PD-L1 blockade or confined to regions isolated from T cells, leaving little opportunity to reinvigorate T cells. Conclusions: PARP inhibition reshaped the TME of BRCA-MUT tumors by inducing tumor fragmentation, sustaining γH2AX-pTBK1 signaling, and restoring CD4+ and CD163+ immune cells, whereas BRCA-WT tumors remained structurally intact and immunosuppressed. PD-1+ T cells localized to PD-L1-negative neighborhoods, and PD-L1+ tumor/myeloid cells were rapidly lost or confined to dying, immune-excluded regions, limiting the impact of PD-L1 blockade. Although PARPi re-engaged T cell programs in BRCA-MUT tumors, strategies beyond PD-L1 inhibition will be required to further enhance T cell infiltration and activation. Citation Format: Kenichi Shimada, Filipa Lynce, Claudine Isaacs, Xue Geng, Edward T. Richardson, Candace Mainor, Mei Wei, Julie M. Collins, Paula R. Pohlmann, Arielle L. Heeke, Kelly F. Zheng, Madeline Townsend, Lauren M. Sloat, Jane Staunton, Stuart J. Schnitt, Hongkun Wang, Joan S. Brugge, Geoffrey I. Shapiro, Jennifer L. Guerriero. Spatially resolved multi-omic profiling reveals BRCA-dependent immune remodeling during PARP inhibition and PD-L1 blockade [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 3434.

Small molecules frequently induce heterogeneous cell-death programs, complicating the mechanistic interpretation and optimization. Here, we investigate the ferroptotic and necrotic activities of the lethal small molecule CIL56 and related analogs. Although structurally similar, these compounds induce chemically separable death phenotypes. A phenotypic suppressor screen further identified distinct sets of small molecules that selectively attenuate ferroptotic or necrotic death. Classification of suppressor compounds based on shared ligand-based target predictions suggested nonoverlapping groups of candidate protein targets linked to each death modality. Together, these results show that integrating phenotypic screening with suppressor classification and target prediction can improve the interpretability of small-molecule phenotypic screens by prioritizing candidate proteins and pathways underlying the observed biological response.

T cells are generally sparse in hormone receptor-positive (HR+) breast cancer, potentially due to limited antigen presentation, but the driving mechanisms of low T cell abundance remains unclear. Therefore, we defined and investigated programs (‘gene modules’), related to estrogen receptor signaling (ERS) and immune signaling using bulk and single-cell transcriptome and multiplexed immunofluorescence of breast cancer tissues from multiple clinical sources and human cell lines. The ERS gene module, dominantly expressed in cancer cells, was negatively associated with immune-related gene modules TNFα/NF-κB signaling and type-I interferon (IFN-I) response, which were expressed in distinct stromal and immune cell types, but also, in part, expressed and preserved as a cancer cell-intrinsic mechanisms. Spatial analysis revealed that ERS strongly correlated with reduced T cell infiltration, potentially due to its association with suppression of TNFα/NF-κB-induced angiogenesis and IFN-I-induced HLA expression in macrophages. Preoperative endocrine therapy in ER+/HER2- breast cancer patients produced better responses in ERS-high patients, with TNFα/NF-κB expression associated with reduced ERS. Targeting these pathways may enhance T cell infiltration in HR+ breast cancer patients.

Abstract Background: Poly (ADP-Ribose) polymerase inhibitors (PARPi) have improved outcomes for BRCA-associated triple negative breast cancer (TNBC); however, resistance develops, resulting in lack of durable responses. Our prior work demonstrated that PARPi activates cGAS/STING signaling, driving CD8+ T-cell recruitment, essential for tumor clearance. These studies led to clinical trials testing PARPi plus immune checkpoint blockade (ICB). However, clinical trials demonstrated no benefit compared to PARPi monotherapy, indicating T-cells in the tumor microenvironment (TME) are inhibited. We previously showed that PARPi induce suppressive tumor-associated macrophages (TAMs) which contribute to PARPi resistance. Removing TAMs with anti-CSF-1R therapy significantly enhanced overall survival (OS) when combined with PARPi and is now being tested in clinical trials (NCT03604692). Here, we test if ICB can enhance the CSF-1R +PARPi combination in both treatment naïve and PARPi-resistant tumors. Methods: Mice bearing naïve or PARPi-resistant BRCA1-deficient TNBC (K14-Cre;Brca1f/f;Trp53f/f) tumors were treated with PARPi ± CSF-1R inhibition (CSF-1Ri) ± ICB and followed for tumor size and OS. Flow cytometry was employed to define immune mechanisms of response. Results: In PARPi-naïve tumors, PARPi + CSF-1Ri significantly increased OS compared to PARPi monotherapy. The combination of PARPi + CSF-1Ri + anti-PD-1 led to a modest improvement in efficacy compared to PARPi + CSF-1Ri treatment. In contrast, the addition of anti-TIM3 to PARPi + CSF-1Ri resulted in durable therapeutic benefit, with a significant increase in OS compared to PARPi + CSF-1Ri. The combination of PARPi + CSF-1Ri + anti-TIM-3 significantly increased CD8+ T-cell infiltration, granzyme B production, and reduction in Tregs indicating an increased anti-tumor immune response. Additionally, anti-TIM-3 induced a pro-inflammatory phenotype in TAMs. In PARPi-resistant tumors TAMs expressed higher levels of CSF-1R compared to PARPi-naïve tumors. Additionally, PARPi-resistant tumors had increased infiltration of Tregs, and higher expression of PD-1 on T-cells, strongly indicating an increased immunosuppressive TME. In PARPi-resistant tumors, anti-CSF-1R therapy restored PARPi efficacy and significantly increased OS. Furthermore, addition of anti-TIM-3 to the anti-CSF-1R + PARPi combination significantly increased OS in PARPi-resistant tumors, whereas anti-PD-1 did not enhance therapy efficacy. Conclusion: PARPi-resistant tumors have increased T-cell exhaustion and infiltration of immunosuppressive TAMs. Importantly, our data shows that targeting TAMs through the CSF-1R axes can overcome acquired PARPi resistance, which can be further enhanced with anti-TIM3 therapy, defining a novel strategy addressing a critical unmet medical need. Citation Format: Adam Nelson, Anita K. Mehta, Madeline G. Townsend, Daniel E. Michaud, Madisson Oliwa, Kelly F. Zheng, Carlos W. Wanderley, Alex P. Gottlieb, Kenichi Shimada, Patrice A. Lee, Nicholas A. Saccomano, Filipa Lynce, Nabihah Tayob, Geoffrey I. Shapiro, Jennifer L. Guerriero. Combined anti-CSF-1R and anti-TIM-3 overcome macrophage-mediated mechanisms of PARP inhibitor (PARPi) resistance in BRCA1-associated triple negative breast 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 7133.

Although mechanical ventilation is a critical intervention for acute respiratory distress syndrome (ARDS), it can trigger an IL-1β-associated complication known as ventilator-induced lung injury. In mice, we found that lipopolysaccharide (LPS) and high-volume ventilation, LPS-HVV, lead to hypoxemia with neutrophil extracellular traps (NETs) formation in the alveoli. Furthermore, Il1r1-/- LPS-HVV mice did not develop hypoxemia and had reduced NETs, indicating that IL-1R1 signaling is important for NETs formation and hypoxemia. Therapeutic hypothermia (TH) is known to reduce the release of inflammatory mediators. In LPS-HVV mice, TH (32°C body temperature) prevented hypoxemia development, reducing albumin leakage, IL-1β, gasdermin D (GSDMD), and NETs formation. We also observed that LPS-primed macrophages, when stimulated at 32°C with ATP or nigericin, release less IL-1β associated with reduced GSDMD cleavage. Thus, hypothermia is an important modulating factor in the NLRP3 inflammasome activation, IL-1β release, and NETs formation, preventing LPS-HVV-induced acute respiratory failure.

BACKGROUND:Alterations in the intestinal microbiota contribute to the pathogenesis of various cardiovascular disorders, but how they affect the development of Kawasaki disease (KD) an acute pediatric vasculitis, remains unclear. METHODS:We used the Lactobacillus casei cell wall extract (LCWE) murine model of KD vasculitis to assess the contribution of the intestinal microbiota to the development of vascular inflammation. We evaluated the severity of vasculitis in microbiota-depleted mice. 16S rRNA gene sequencing was used to characterize the fecal microbiome composition of LCWE-injected mice. Some groups of mice were orally treated with selected live or pasteurized bacteria, short-chain fatty acids, or Amuc_1100, the Toll-like receptor 2 signaling outer membrane protein from Akkermansia muciniphila, and their impact on vasculitis development was assessed. RESULTS:We report that depleting the gut microbiota reduces the development of cardiovascular inflammation in a murine model mimicking KD vasculitis. The development of cardiovascular lesions was associated with alterations in the intestinal microbiota composition and, notably, a decreased abundance of Akkermansia muciniphila and Faecalibacterium prausnitzii. Oral supplementation with either of these live or pasteurized individual bacteria or with short-chain fatty acids produced by them attenuated cardiovascular inflammation, as reflected by decreased local immune cell infiltrations. Treatment with Amuc_1100 also reduced the severity of vascular inflammation. CONCLUSIONS:This study reveals an underappreciated gut microbiota-cardiovascular inflammation axis in KD vasculitis pathogenesis and identifies specific intestinal commensals that regulate vasculitis in mice by producing metabolites or via extracellular proteins capable of enhancing and supporting gut barrier function.

Background We previously showed that Lactobacillus casei cell wall extract‐induced Kawasaki disease (KD) vasculitis significantly accelerates atherosclerosis in hypercholesterolemic mice on high‐fat diet. Here, we investigated the contribution of IL‐1 (interleukin‐1) signaling on vascular smooth muscle cells in this model. Methods Tamoxifen‐inducible vascular smooth muscle cell‐specific IL‐1 receptor (Il1r1) knockout (SMCΔ/Δ) mice and Il1r1SMCWT/WT [wildtype/wildtype] littermate controls, all on ApoE−/− background, were injected with either PBS or Lactobacillus casei cell wall extract. Two weeks later, mice were fed a tamoxifen diet for 2 weeks to induce Il1r1 deletion on vascular smooth muscle cells before being exposed to 8 weeks of Western diet to promote atherosclerosis. Results KD vasculitis led to a significant acceleration of atherosclerosis. Il1r1SMCΔ/Δ mice had significantly diminished atherosclerotic plaque size, macrophage infiltration, and necrotic core formation in the aortic root, as well as diminished lipid accumulation in the aorta en face compared with control mice, despite similar serum cholesterol levels. Il1r1SMCΔ/Δ mice also had significantly diminished expression of endothelial adhesion molecules VCAM‐1 (vascular cell adhesion molecule 1) and ICAM‐1 (intercellular adhesion molecule 1) in the lesion area, as well as reduced serum MCP‐1 (monocyte chemotaxis protein‐1) levels compared with Il1r1SMCWT/WT control mice. Monocyte and macrophage recruitment was significantly reduced in the Il1r1SMCΔ/Δ group compared with the Il1r1SMCWT/WT group. Conclusions Our results suggest an important pathophysiologic link between IL‐1 signaling on vascular smooth muscle cells and subsequent acceleration of atherosclerosis in hypercholesterolemic mice following KD vasculitis. Thus, further studies are warranted to investigate the role of IL‐1 signaling not only in acute KD but also in the subsequent vascular remodeling and long‐term complications of KD vasculitis, including accelerated atherosclerosis.

Novel anti-HER2 antibody-drug conjugates (ADCs), such as trastuzumab deruxtecan (T-DXd), have shown efficacy in tumors with varying HER2 expression, including HER2-low and even tumors with minimal HER2 presence. This has sparked interest in the biology underlying the HER2 expression spectrum. Using molecular and multiplexed imaging, we revealed distinct immune and stromal features in treatment-naive, hormone receptor-positive (HR+) HER2-low versus HER2-0 tumors. HER2-0 tumors exhibit inflammatory and tissue remodeling gene signatures, with enrichment of APOE⁺ tumor-associated macrophages (TAMs) and DOCK4⁺ CD4 T cells. In contrast, HER2-low tumors are more immunosuppressed, with elevated cell cycle, metabolic, and estrogen signaling pathways, suggesting increased proliferative activity. These findings underscore key biological differences between HR+ HER2-low and HER2-0 breast cancers, and may inform more tailored therapeutic strategies. Statement of significance:This study revealed the distinct biological profiles of HR+ HER2-low and HER2-0 breast tumors. HER2-0 tumors exhibit inflammatory and tissue remodeling signatures, whereas HER2-low tumors have elevated cell cycle, metabolic, and estrogen signaling. These insights may help refine therapeutic approaches to improve outcomes for breast cancer patients.

Kawasaki Disease (KD) is a febrile systemic vasculitis and the leading cause of acquired heart diseases in children. Intravenous immunoglobulin (IVIG) treatment reduces the incidence of coronary artery aneurysms (CAAs), which occur in up to 25% of untreated children. Autopsies of tissues revealed neutrophils (Neu) infiltrating heart tissues in acute KD. Neu are recruited to injury sites via CXCR2, and they can form NETs induced by IL-1b to kill pathogens. Using the Lactobacillus casei cell-wall extract (LCWE) mouse model of KD vasculitis, we previously showed that Neu in lesions express Nlrp3 and Il1b. However, the role of Neu in KD remains unclear. Our time-course flow cytometric analysis showed increased CXCR2+ Neu in the peritoneum and blood of LCWE-injected mice at 24 hrs & 7d post-injection, respectively. Increased Neu infiltration in the heart and abdominal aorta (AA) of LCWE-injected mice from day 7 after injection had low expression of CXCR2. Cxcr2–/– mice were not protected, but mice with Neu-specific Nlrp3 deletion were significantly protected from vasculitis. Circulating myeloperoxidase (MPO) levels were increased 24 hours after LCWE injection and H3-Cit+MPO+ Neu (NETs) were detected by immunofluorescence in AA tissues of LCWE-injected mice. Our results indicate that Neu are rapidly mobilized, infiltrate the vascular tissues, and significantly contribute to LCWE-induced KD vasculitis through a mechanism driven by the NLRP3/IL-1b axis that may involve NET formation. NIH5R01AI157274-05 Immune Mechanisms of Human Disease (HUM)

T cells are generally sparse in hormone receptor-positive (HR+) breast cancer, potentially due to limited antigen presentation, but the driving mechanisms of low T cell abundance remains unclear. Therefore, we defined and investigated programs ('gene modules'), related to estrogen receptor signaling (ERS) and immune signaling using bulk and single-cell transcriptome and multiplexed immunofluorescence of breast cancer tissues from multiple clinical sources and human cell lines. The ERS gene module, dominantly expressed in cancer cells, was negatively associated with immune-related gene modules TNFα/NF-κB signaling and type-I interferon (IFN-I) response, which were expressed in distinct stromal and immune cell types, but also, in part, expressed and preserved as a cancer cell-intrinsic mechanisms. Spatial analysis revealed that ERS strongly correlated with reduced T cell infiltration, potentially due to its association with suppression of TNFα/NF-κB-induced angiogenesis and IFN-I-induced HLA expression in macrophages. Preoperative endocrine therapy in ER+/HER2-breast cancer patients produced better responses in ERS-high patients, with TNFα/NF-κB expression associated with reduced ERS. Targeting these pathways may enhance T cell infiltration in HR+ breast cancer patients. Statement of Significance:This study elucidates the immunosuppressive role of ER signaling in breast cancer, highlighting a complex interplay between cancer, stromal, and immune cells and reveals potential approaches to enhance immunogenicity in HR+ breast cancer. These findings offer crucial insights into immune evasion in breast cancer and identify strategies to enhance T cell abundance.

Kawasaki Disease (KD), a pediatric acute febrile systemic vasculitis, is the leading cause of acquired heart diseases in children. Coronary artery aneurysms (CAAs) occur in up to 25% of untreated children, which is reduced to 5% with intravenous immunoglobulin (IVIG) treatment. However, up to 20% of KD patients are refractory to IVIG and at higher risk of developing CAAs. This highlights the need to characterize the immune mechanisms mediating KD to develop more efficient therapies. IL-1β plays a key role in KD pathogenesis. IL-33, a member of the IL-1 cytokine family, is released upon inflammation and tissue damage and exerts its effects by binding to its receptor ST2 ( Il1rl1 ). Circulating levels of IL-33 are elevated in KD patients during the acute phase of the disease. However, if and how IL-33 contributes to cardiovascular lesion development in KD remains unknown. Using the Lactobacillus casei cell wall extract (LCWE) murine model of KD vasculitis, we observed increased Il33 mRNA expression in hearts and abdominal aorta aneurysms of LCWE-injected mice. While ST2 was detected by immunofluorescence in the hearts of both control and LCWE-injected mice, its expression was increased in the abdominal aortas of LCWE-injected mice. In contrast, IL-33 expression was only increased in inflamed cardiovascular tissues of LCWE-injected mice. Single-cell RNA-sequencing and flow cytometric analysis of abdominal aortas, as well as spatial transcriptomics of heart tissues from LCWE-injected mice, indicated that Il33 transcripts were expressed primarily by stromal cells, such as fibroblasts, endothelial cells, and vascular smooth muscle cells. On the other hand, Il1rl1 transcripts were highly expressed by tissue infiltrating immune cells, such as macrophages, eosinophils, and neutrophils. Blocking IL-33, using either Il33 -/- mice or an anti-IL-33 antibody, significantly attenuated LCWE-induced KD vasculitis. In vitro, IL-33 treatment of LCWE-stimulated bone marrow-derived macrophages boosted their IL-1β production. Overall, our results indicate that IL-33, produced by stromal cells, may promote LCWE-induced KD vasculitis by increasing the release of IL-1β by tissue infiltrating immune cells, and this axis could therapeutically be targeted in KD.

Abstract Hormone receptor-positive (HR+) breast tumors are the most frequently diagnosed type of breast cancer (~70%) and are characterized by the expression of the estrogen receptor and/or the progesterone receptor. HR+ breast tumors derive limited benefit from immune checkpoint therapy (ICT), which can be at least partially attributed in part, to low levels of T cell infiltration and low expression of T cell immune checkpoint molecules. In other solid tumors, targeting components of the tumor microenvironment outside of T cells have shown the ability to enhance ICT responses, however, such targets have been relatively unexplored in HR+ breast cancer. We hypothesize that there are unidentified targetable non-lymphocyte immune populations within the HR+ breast tumor microenvironment, which can be targeted to increase response to ICT. We performed paired bulk RNA sequencing and cyclic immunofluorescence (CyCIF) from untreated human HR+ tumors (n=30) as well as single-cell RNA sequencing (scRNA-seq) on a subset (N=17) of the tumors, to characterize the spatial composition of the immune infiltrate and identify gene expression profiles that correlate with T cell infiltration. We have identified tumor-associated macrophages (TAMs) as being the immune cell population most abundant in HR+ tumors by both scRNA-seq & CyCIF. We identified SPP1+ CD36+ expressing macrophages to be significantly enriched in T cell-low compared to T cell-high HR+ tumors. These SPP1+ CD36+ macrophages have been previously linked to lipid metabolism in the tumor microenvironment and we confirmed such with gene set enrichment analysis. Inversely, T cell high HR+ tumors displayed a significant enrichment of MUCL1+APOD+ macrophages expressing high levels of MHC class II molecules and enriched for gene sets relating to antigen presentation and interferon responses. Collectively, these findings put forth two populations of macrophages within HR+ tumors as novel immunotherapeutic targets for further investigation to enhance T cell responses and ICT. Citation Format: Daniel Michaud, Kenichi Shimada, Kelly Zheng, Cheryl Gu, Yvonne Cui, Jonathan Goldberg, Esther Ogayo, Peter Sorger, Sandro Santagata, Elizabeth Mittendorf, Jennifer Guerriero. Characterization of the hormone receptor-positive breast tumor immune microenvironment using single cell transcriptomics and multiplex immunofluorescence [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Breast Cancer Research; 2023 Oct 19-22; San Diego, California. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_1):Abstract nr A042.

Emerging data suggests that HER2 intratumoral heterogeneity (ITH) is associated with therapy resistance, highlighting the need for new strategies to assess HER2 ITH. A promising approach is leveraging multiplexed tissue analysis techniques such as cyclic immunofluorescence (CyCIF), which enable visualization and quantification of 10–60 antigens at single-cell resolution from individual tissue sections. In this study, we qualified a breast cancer-specific antibody panel, including HER2, ER, and PR, for multiplexed tissue imaging. We then compared the performance of these antibodies against established clinical standards using pixel-, cell- and tissue-level analyses, utilizing 866 tissue cores (representing 294 patients). To ensure reliability, the CyCIF antibodies were qualified against HER2 immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) data from the same samples. Our findings demonstrate the successful qualification of a breast cancer antibody panel for CyCIF, showing high concordance with established clinical antibodies. Subsequently, we employed the qualified antibodies, along with antibodies for CD45, CD68, PD-L1, p53, Ki67, pRB, and AR, to characterize 567 HER2+ invasive breast cancer samples from 189 patients. Through single-cell analysis, we identified four distinct cell clusters within HER2+ breast cancer exhibiting heterogeneous HER2 expression. Furthermore, these clusters displayed variations in ER, PR, p53, AR, and PD-L1 expression. To quantify the extent of heterogeneity, we calculated heterogeneity scores based on the diversity among these clusters. Our analysis revealed expression patterns that are relevant to breast cancer biology, with correlations to HER2 ITH and potential relevance to clinical outcomes.

Objective: We have previously shown that Lactobacillus casei cell wall extract (LCWE)-induced Kawasaki disease (KD) vasculitis significantly accelerates atherosclerosis in hypercholesterolemic mice on high fat diet. IL-1 signaling is known to play a key role in both KD vasculitis and in the development of atherosclerosis. Here, we investigated the contribution of IL-1 signaling on vascular smooth muscle cells (VSMCs) in KD vasculitis-induced acceleration of atherosclerosis. Methods: Tamoxifen-inducible VSMC-specific IL-1 receptor ( Il1r1) knockout ( Myh11 Cre -ERT2 Il1r1 Δ/Δ ) mice and Il1r1 fl/fl littermate controls, all on ApoE -/- background, were injected with either PBS or LCWE. Following induction of KD vasculitis for 2 weeks, mice were fed a tamoxifen diet for 2 weeks to induce Il1r1 deletion on VSMCs, before being exposed to 8 weeks of Western diet to promote atherosclerosis. Results: KD vasculitis was associated with a significant acceleration of atherosclerosis, as expected. Myh11 Cre -ERT2 Il1r1 Δ/Δ mice had significantly diminished atherosclerotic plaque size, lipid composition, macrophage infiltration and necrotic core formation in aortic root as well as diminished lipid accumulation in aorta en face measurements compared with Il1r1 fl/fl control mice despite similar cholesterol levels. We also observed that Myh11 Cre -ERT2 Il1r1 Δ/Δ mice had significantly diminished endothelial adhesion molecules VCAM-1 and ICAM-1 expression in the lesion area and serum monocyte chemotaxis protein-1 (MCP-1) level compared with Il1r1 fl/fl control mice, consistent with the reduction of macrophage infiltration that we observed. Conclusions: Our results suggest an important pathophysiologic link between IL-1 signaling, specifically on VSMCs, and subsequent acceleration of atherosclerosis in hypercholesterolemic mice following KD vasculitis. Thus, further studies are warranted on the role of IL-1 signaling not only in acute KD, but also in the subsequent vascular remodeling and complications following acute KD vasculitis including atherosclerosis.

Purpose Predicting progression of mild cognitive impairment (MCI) to Alzheimer’s disease (AD) or dementia with Lewy bodies (DLB) is important. We evaluated morphological and functional differences between MCI with Lewy bodies (MCI-LB) and MCI due to AD (MCI-AD), and a method for differentiating between these conditions using brain MRI and brain perfusion SPECT. Methods A continuous series of 101 subjects, who had visited our memory clinic and met the definition of MCI, were enrolled retrospectively. They were consisted of 60 MCI-LB and 41 MCI-AD subjects. Relative cerebral blood flow (rCBF) on SPECT images and relative brain atrophy on MRI images were evaluated. We performed voxel-based analysis and visually inspected brain perfusion SPECT images for regional brain atrophy, occipital hypoperfusion and the cingulate island sign (CIS), for differential diagnosis of MCI-LB and MCI-AD. Results MRI showed no significant differences in regional atrophy between the MCI-LB and MCI-AD groups. In MCI-LB subjects, occipital rCBF was significantly decreased compared with MCI-AD subjects ( p < 0.01, family wise error [FWE]-corrected). Visual inspection of occipital hypoperfusion had sensitivity, specificity, and accuracy values of 100%, 73.2% and 89.1%, respectively, for differentiating MCI-LB and MCI-AD. Occipital hypoperfusion was offered higher diagnostic utility than the CIS. Conclusions The occipital lobe was the region with significantly decreased rCBF in MCI-LB compared with MCI-AD subjects. Occipital hypoperfusion on brain perfusion SPECT may be a more useful imaging biomarker than the CIS for visually differentiating MCI-LB and MCI-AD.