Citations

Abstract Dissemination of ovarian cancer cells can lead to inoperable metastatic lesions in the bowel and omentum that cause patient death. Here we show that LRRC15, a type-I 15-leucine–rich repeat-containing membrane protein, highly overexpressed in ovarian cancer bowel metastases compared with matched primary tumors and acts as a potent promoter of omental metastasis. Complementary models of ovarian cancer demonstrated that LRRC15 expression leads to inhibition of anoikis-induced cell death and promotes adhesion and invasion through matrices that mimic omentum. Mechanistically, LRRC15 interacted with β1-integrin to stimulate activation of focal adhesion kinase (FAK) signaling. As a therapeutic proof of concept, targeting LRRC15 with the specific antibody–drug conjugate ABBV-085 in both early and late metastatic ovarian cancer cell line xenograft models prevented metastatic dissemination, and these results were corroborated in metastatic patient-derived ovarian cancer xenograft models. Furthermore, treatment of 3D-spheroid cultures of LRRC15-positive patient-derived ascites with ABBV-085 reduced cell viability. Overall, these data uncover a role for LRRC15 in promoting ovarian cancer metastasis and suggest a novel and promising therapy to target ovarian cancer metastases. Significance: This study identifies that LRRC15 activates β1-integrin/FAK signaling to promote ovarian cancer metastasis and shows that the LRRC15-targeted antibody–drug conjugate ABBV-085 suppresses ovarian cancer metastasis in preclinical models.

Abstract While chronological age is one of the most influential determinants of post-stroke outcomes, little is known of the impact of neuroimaging-derived biological brain age. We here first examine whether radiomics analysis of the texture of brain T2-FLAIR MRI images can be used to predict brain age in stroke patients. We then assess the clinical determinants of accelerated brain aging and, finally, its impact on post-stroke functional outcomes. Leveraging a multisite cohort of 4,163 ischemic stroke patients, we show that older-appearing patients have more hypertension, diabetes mellitus, prior strokes, and smoking history and are more likely to develop worse post-stroke outcomes than their younger-appearing counterparts. Our results strengthen the importance of preventive medicine for maintaining brain health in stroke patients as they age and suggest a novel methodology to capture previously undescribed prognostic information available on commonly acquired MRI sequences during routine stroke care.

A considerable subset of gynecologic cancer patients experience disease recurrence or acquired resistance, which contributes to high mortality rates in ovarian cancer (OC). Our prior studies showed that quinacrine (QC), an antimalarial drug, enhanced chemotherapy sensitivity in treatment-refractory OC cells, including artificially generated chemoresistant and high-grade serous OC cells. In this study, we investigated QC-induced transcriptomic changes to uncover its cytotoxic mechanisms of action. Isogenic pairs of OC cells generated to be chemoresistant and their chemosensitive counterparts were treated with QC followed by RNA-seq analysis. Validation of selected expression results and database comparison analyses indicated the ribosomal biogenesis (RBG) pathway is inhibited by QC. RBG is commonly upregulated in cancer cells and is emerging as a drug target. We found that QC attenuates the in vitro and in vivo expression of nucleostemin (NS/GNL3), a nucleolar RBG and DNA repair protein, and the RPA194 catalytic subunit of Pol I that results in RBG inhibition and nucleolar stress. QC promotes the redistribution of fibrillarin in the form of extranuclear foci and nucleolar caps, an indicator of nucleolar stress conditions. In addition, we found that QC-induced downregulation of NS disrupted homologous recombination repair both by reducing NS protein levels and PARylation resulting in reduced RAD51 recruitment to DNA damage. Our data suggest that QC inhibits RBG and this inhibition promotes DNA damage by directly downregulating the NS–RAD51 interaction. Additionally, QC showed strong synergy with PARP inhibitors in OC cells. Overall, we found that QC downregulates the RBG pathway, induces nucleolar stress, supports the increase of DNA damage, and sensitizes cells to PARP inhibition, which supports new therapeutic stratagems for treatment-refractory OC. Our work offers support for targeting RBG in OC and determines NS to be a novel target for QC.

Significance Glucocorticoids are widely prescribed antiinflammatory drugs that suppress inflammatory gene expression through activation of the glucocorticoid receptor (GR); however, the mechanisms of GR-mediated repression are not fully understood. We show here that bromodomain containing 9 (BRD9), a component of the SWI/SNF chromatin remodeling complex, modulates GR activity in bone marrow-derived macrophages. Loss of BRD9 activity in macrophages attenuated the response to liposaccharides and interferon inflammatory stimuli. Notably, BRD9 inhibition synergized with the synthetic glucocorticoid dexamethasone to suppress the inflammatory response in macrophages. Our data support a model in which BRD9 restricts GR binding at a subset of inflammatory related genes, and suggests that BRD9 inhibitors may increase the efficacy of glucocorticoids.

Background Women with cardiomyopathy (CM) are often advised against pregnancy due to risk for major adverse cardiovascular events (MACE). However, the impact of CM subtype on maternal MACE is not understood, and so we sought to evaluate the influence of CM phenotype on maternal outcomes, as well as the effect on immediate and late left ventricular function. Methods We evaluated all pregnant women in our high-risk maternal cardiovascular programme (2009–2019). Composite maternal MACE included: death, inotrope use, left ventricular assist device, orthotopic heart transplant and/or escalation in transplant listing status, acute decompensated heart failure and sustained ventricular arrhythmia. Results Among 875 women followed, 32 had CM (29±7 years old, left ventricular ejection fraction (LVEF) 41%±12%): 3 ischaemic CM (ICM), 10 peripartum CM (PPCM) and 19 non-ICM (NICM). MACE events occurred in 6 (18%) women (PPCM: 2 (33%), NICM: 4 (67%)). There was no difference in LVEF at baseline, however, women with MACE had significantly lower LVEF both early (LVEF: 27±5% vs . 41±2%, p<0.05) and late post partum (LVEF: 28±5% vs . 44±2%, p<0.01). Conclusions In this contemporary cohort of women with CM, maternal MACE rates were lower than previously reported, and were less common in PPCM as compared with ICM and NICM. Heart function in women with MACE was negatively impacted immediately after delivery and in late postpartum follow-up, suggesting that pregnancy itself likely has influence on future left ventricular function in women with underlying CM.

AbstractThe development of novel agents has transformed the treatment paradigm for multiple myeloma, with minimal residual disease (MRD) negativity now achievable across the entire disease spectrum. Bone marrow–based technologies to assess MRD, including approaches using next-generation flow and next-generation sequencing, have provided real-time clinical tools for the sensitive detection and monitoring of MRD in patients with multiple myeloma. Complementary liquid biopsy–based assays are now quickly progressing with some, such as mass spectrometry methods, being very close to clinical use, while others utilizing nucleic acid–based technologies are still developing and will prove important to further our understanding of the biology of MRD. On the regulatory front, multiple retrospective individual patient and clinical trial level meta-analyses have already shown and will continue to assess the potential of MRD as a surrogate for patient outcome. Given all this progress, it is not surprising that a number of clinicians are now considering using MRD to inform real-world clinical care of patients across the spectrum from smoldering myeloma to relapsed refractory multiple myeloma, with each disease setting presenting key challenges and questions that will need to be addressed through clinical trials. The pace of advances in targeted and immune therapies in multiple myeloma is unprecedented, and novel MRD-driven biomarker strategies are essential to accelerate innovative clinical trials leading to regulatory approval of novel treatments and continued improvement in patient outcomes.

Abstract In the present study, acute onset of severe lupus nephritis was successfully treated in mice using a new, benzamide‐linked, small molecule that targets immune modulation and the NLRP3 inflammasome. Specifically, 6‐(2,4‐difluorophenyl)‐3‐(3‐(trifluoromethyl)phenyl)‐2H‐benzo[e][1,3]oxazine‐2,4(3H)‐dione (Cf‐02) (a) reduced serum levels of IgG anti‐dsDNA, IL‐1β, IL‐6, and TNF‐α, (b) inhibited activation of dendritic cells and differentially regulated T cell functions, and (c) suppressed the NF‐κB/NLRP3 inflammasome axis, targeting priming and activating signals of the inflammasome. Moreover, treatment with Cf‐02 significantly inhibited secretion of IL‐1β in lipopolysaccharide‐stimulated macrophages, but this effect was abolished by autophagy induction. These results recommend Cf‐02 as a promising drug candidate for the serious renal conditions associated with systemic lupus erythematosus. Future investigations should examine whether Cf‐02 may also be therapeutic in other types of chronic kidney disease involving NLRP3 inflammasome‐driven signaling.

The aim of this study was to characterise a recently identified adult smooth muscle stem-like/progenitor cell (SMSPC) and exploit the ability to differentiate contractile smooth muscle cells (SMC) from SMSPCs facilitating tissue engineering of small to medium arteries, an approach which is hampered by inadequate sources of, and scale up methodologies for autologous SMCs. We initially identified a novel SMSPC in the bone marrow (BM) of rats that retained classic stem cell-like characteristics (clonogenicity, unlimited self-renewal, high telomerase activity, expression of stem cell markers) whilst expressing low levels of SMC-like transcripts. Spontaneous differentiation favoured a SMC phenotype where ~20-fold increases in calponin and SM-MHC protein expression were observed 10 days post-embryoid body formation, an effect augmented by TGFβ (P < 0.0001). Differentiation of SMSPCs from an undifferentiated state towards contractile SMCs was Myocd-dependent. Overexpression of Myocd in SMSPCs increased their percentage contraction in response to AngII (P < 0.05) and KCL (P < 0.05) and Ca2+ signalling to levels indistinguishable from rat SMCs. Knockdown of SMC-specific repressors resulted in Myocd-dependent SMC differentiation of SMSPCs. Taking advantage of the fact that SMSPCs possessed unlimited self-renewal capacity ex vivo and could be successfully reprogrammed into functional SMCs, we determined the vascular tissue engineering potential of SMSPCs and showed these cells integrate as viable tissue engineered vascular grafts in vivo. Specifically, after 1 month implantation, a Myocd-GFP+/Isl1+ smooth muscle layer was observed in the grafts along with a vWF+ luminal endothelial layer and multi-layered collagen and elastin fibre formation throughout the graft wall. We have recently isolated cells with similar SMSPC phenotype and differentiation potential from human peripheral blood. This study demonstrates that adult SMSPCs derived from rat BM and human blood can be reprogrammed to efficiently generate large quantities of mature contractile SMCs, displaying great utility as a cellular backbone for tissue engineered vascular grafts, making them an attractive source for vascular cell therapy and surgical applications.

Background: Assessment of coexisting pericardial and myocardial disease in constrictive pericarditis (CP) remains a diagnostic challenge and decision for pericardiectomy depends on the degree of pericardial versus myocardial restraint limiting left ventricular (LV) filling. Early diastolic longitudinal mitral annulus velocity (Ea) can help to differentiate CP from restrictive cardiomyopathy. Recently, acceleration rate of Ea has been shown to be an index of LV myocardial relaxation. We therefore assessed acceleration (Ea-AR) and deceleration (Ea-DR) rate of Ea in patients with CP before and after pericardiectomy. Methods: We retrospectively studied patients (n=42) with surgically confirmed CP who underwent radical pericardiectomy between 2003–2006 at Mayo Clinic Rochester. Ea-AR and Ea-DR slopes were measured before (pre-Echo) and after (post-Echo) pericardiectomy. Patients were divided into primary CP (idiopathic & acute pericarditis with presumed normal myocardial function) and secondary CP (cardiac surgery & chest irradiation with presumed abnormal myocardial function). Results: Ea-AR and Ea-DR changed significantly after pericardiectomy in primary CP patients, however remained similar in secondary CP patients. Diagnostic accuracy of Ea-AR, Ea-DR and Ea to discriminate primary versus secondary CP by ROC analysis was 0.88, 0.80 and 0.81 respectively. Conclusion: Assessment of Ea-AR and Ea-DR in patients with CP is useful to discriminate primary from secondary CP and may help to predict coexistence of myocardial disease: Prepericardiectomy Ea-AR and Ea-DR appear to reflect the interaction of intrinsic myocardial relaxation with enhanced early LV filling. The lack of decrease of Ea-AR and Ea-DR in patients with secondary CP seems to indicate a primarily restrictive component. The significant decrease of Ea-DR in patients with primary CP after pericardiectomy could reflect abolition of a predominant pericardial limitation to LV filling. Early Diastolic Longitudinal Mitral Annulus Motion before and after Pericardiectomy