Faculty Bibliography

PURPOSE/OBJECTIVE:Women treated with radiotherapy before 30 years of age have increased risk of developing breast cancer at an early age. Here we sought to investigate mechanisms by which radiation promotes aggressive cancer. EXPERIMENTAL DESIGN/METHODS:null mammary transplants after irradiation of the target epithelium or host using immunocompetent and incompetent mice, some which were treated with aspirin. RESULTS:null mammary transplantation, cancers also established an iTME, which pointed to a critical role for myeloid cells. Consistent with this, irradiated mammary glands contained more macrophages and human cells co-cultured with polarized macrophages underwent dysplastic morphogenesis mediated by interferon γ. Treating mice with low-dose aspirin for 6 months post-irradiation prevented establishment of an iTME and resulted in less aggressive tumors. CONCLUSIONS:These data show that radiation acts via non-mutational mechanisms to promote markedly immunosuppressive features of aggressive, radiation-preceded breast cancers.

Acyl-CoA:cholesterol acyltransferase (ACAT) mediates cellular cholesterol esterification. In atherosclerotic plaque macrophages, ACAT promotes cholesteryl ester accumulation, resulting in foam cell formation and atherosclerosis progression. Its complete inactivation in mice, however, showed toxic effects because of an excess of free cholesterol (FC) in macrophages, which can cause ER stress, cholesterol crystal formation, and inflammasome activation. Our previous studies showed that long-term partial ACAT inhibition, achieved by dietary supplementation with Fujirebio F1394, delays atherosclerosis progression in apoprotein E-deficient (Apoe^-/- ) mice by reducing plaque foam cell formation without inflammatory or toxic effects. Here, we determined whether short-term partial inhibition of ACAT, in combination with an enhanced systemic FC acceptor capacity, has synergistic benefits. Thus, we crossbred Apoe^-/- with human apoprotein A1-transgenic (APOA1^tg/tg ) mice, which have elevated cholesterol-effluxing high-density lipoprotein particles, and subjected Apoe^-/- and APOA1^tg/tg/Apoe^-/- mice to an atherogenic diet to develop advanced plaques. Then mice were either euthanized (baseline) or fed purified standard diet with or without F1394 for four more weeks. Plaques of APOA1^tg/tg/Apoe^-/- mice fed F1394 showed a 60% reduction of macrophages accompanied by multiple other benefits, such as reduced inflammation and favorable changes in extracellular composition, in comparison to Apoe^-/- baseline mice. In addition, there was no accumulation of cholesterol crystals or signs of toxicity. Overall, these results show that short-term partial ACAT inhibition, coupled to increased cholesterol efflux capacity, favorably remodels atherosclerosis lesions, supporting the potential of these combined therapies in the treatment of advanced atherosclerosis. Significance Statement Short-term pharmacological inhibition of ACAT-mediated cholesterol esterification, in combination with increased free cholesterol efflux acceptors, has positive effects in mice by (1) reducing the inflammatory state of the plaque macrophages, and (2) favoring compositional changes associated with plaque stabilization. These effects occur without toxicity, showing the potential of these combined therapies in the treatment of advanced atherosclerosis.

SUMMARY/CONCLUSIONS:The authors present indocyanine green angiography to assess the effects of hyperbaric oxygen therapy and as a potential biomarker to predict healing of chronic wounds. They hypothesize that favorable initial response to hyperbaric oxygen therapy (improved perfusion) would be an early indicator of eventual response to the treatment (wound healing). Two groups were recruited: patients with chronic wounds and unwounded healthy controls. Inclusion criteria included adults with only one active wound of Wagner grade III diabetic foot ulcer or caused by soft-tissue radionecrosis. Patients with chronic wounds underwent 30 to 40 consecutive hyperbaric oxygen therapy sessions, once per day, 5 days per week; controls underwent two consecutive sessions. Indocyanine green angiography was performed before and after the sessions, and perfusion patterns were analyzed. Healing was determined clinically and defined as full skin epithelialization with no clinical evidence of wound drainage. Fourteen chronic-wound patients and 10 controls were enrolled. Unlike unwounded healthy volunteers, a significant increase in indocyanine green angiography perfusion was found in chronic-wound patients immediately after therapy (p < 0.03). Moreover, the authors found that 100 percent of the wounds that demonstrated improved perfusion from session 1 to session 2 went on to heal within 30 days of hyperbaric oxygen therapy completion, compared with none in the subgroup that did not demonstrate improved perfusion (p < 0.01). This study demonstrates a beneficial impact of hyperbaric oxygen therapy on perfusion in chronic wounds by ameliorating hypoxia and improving angiogenesis, and also proposes a potential role for indocyanine green angiography in early identification of those who would benefit the most from hyperbaric oxygen therapy. CLINICAL QUESTION/LEVEL OF EVIDENCE/METHODS:Therapeutic, IV.

Rationale: The cardiac sodium channel NaV1.5 has a fundamental role in excitability and conduction. Previous studies have shown that sodium channels cluster together in specific cellular subdomains. Their association with intracellular organelles in defined regions of the myocytes, and the functional consequences of that association, remain to be defined. Objective: To characterize a subcellular domain formed by sodium channel clusters in the crest region of the myocytes, and the subjacent subsarcolemmal mitochondria (SSM).Methods and Results: Through a combination of imaging approaches including super-resolution microscopy and electron microscopy we identified, in adult cardiac myocytes, a NaV1.5 subpopulation in close proximity to SSM; we further found that SSM preferentially host the mitochondrial Na+/Ca2+ exchanger (NCLX). This anatomical proximity led us to investigate functional changes in mitochondria resulting from sodium channel activity. Upon TTX exposure, mitochondria near NaV1.5 channels accumulated more Ca2+ and showed increased ROS production when compared to interfibrillar mitochondria. Finally, crosstalk between NaV1.5 channels and mitochondria was analyzed at a transcriptional level. We found that SCN5A and SLC8B1 (which encode NaV1.5 and NCLX, respectively) are negatively correlated both in a human transcriptome dataset (GTEx) and in human-induced pluripotent stem cell-derived cardiac myocytes deficient in SCN5A. Conclusions: We describe an anatomical hub (a couplon) formed by sodium channel clusters and SSM. Preferential localization of NCLX to this domain allows for functional coupling where the extrusion of Ca2+ from the mitochondria is powered, at least in part, by the entry of sodium through NaV1.5 channels. These results provide a novel entry-point into a mechanistic understanding of the intersection between electrical and structural functions of the heart.

Motile cilia power cell locomotion and drive extracellular fluid flow by propagating bending waves from their base to tip. The coordinated bending of cilia requires mechanoregulation by the radial spoke (RS) protein complexes and the microtubule central pair (CP). Despite their importance for ciliary motility across eukaryotes, the molecular function of the RSs is unknown. Here, we reconstituted the Chlamydomonas reinhardtii RS head that abuts the CP and determined its structure using single-particle cryo-EM to 3.1-Ã… resolution, revealing a flat, negatively charged surface supported by a rigid core of tightly intertwined proteins. Mutations in this core, corresponding to those involved in human ciliopathies, compromised the stability of the recombinant complex, providing a molecular basis for disease. Partially reversing the negative charge on the RS surface impaired motility in C. reinhardtii. We propose that the RS-head architecture is well-suited for mechanoregulation of ciliary beating through physical collisions with the CP.

Importance/UNASSIGNED:To date, no study has characterized the mucocutaneous features seen in hospitalized children with multisystem inflammatory syndrome in children (MIS-C) or the temporal association of these findings with the onset of systemic symptoms. Objective/UNASSIGNED:To describe the mucocutaneous findings seen in children with MIS-C during the height of the coronavirus disease 2019 (COVID-19) pandemic in New York City in 2020. Design, Setting, and Participants/UNASSIGNED:A retrospective case series was conducted of 35 children admitted to 2 hospitals in New York City between April 1 and July 14, 2020, who met Centers for Disease Control and Prevention and/or epidemiologic criteria for MIS-C. Main Outcomes and Measures/UNASSIGNED:Laboratory and clinical characteristics, with emphasis on mucocutaneous findings, of children who met criteria for MIS-C. The characterization of mucocutaneous features was verified by 2 board-certified pediatric dermatologists. Results/UNASSIGNED:Twenty-five children (11 girls [44%]; median age, 3 years [range, 0.7-17 years]) were identified who met definitional criteria for MIS-C; an additional 10 children (5 girls [50%]; median age, 1.7 years [range, 0.2-15 years]) were included as probable MIS-C cases (patients met all criteria with the exception of laboratory test evidence of severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2] infection or known exposure). The results of polymerase chain reaction tests for SARS-CoV-2 were positive for 10 patients (29%), and the results of SARS-CoV-2 immunoglobulin G tests were positive for 19 patients (54%). Of the 35 patients, 29 (83%) exhibited mucocutaneous changes, with conjunctival injection (n = 21), palmoplantar erythema (n = 18), lip hyperemia (n = 17), periorbital erythema and edema (n = 7), strawberry tongue (n = 8), and malar erythema (n = 6) being the most common findings. Recognition of mucocutaneous findings occurred a mean of 2.7 days (range, 1-7 days) after the onset of fever. The duration of mucocutaneous findings varied from hours to days (median duration, 5 days [range, 0-11 days]). Neither the presence nor absence of mucocutaneous findings was significantly associated with overall disease severity. Conclusions and Relevance/UNASSIGNED:In this case series of hospitalized children with suspected MIS-C during the COVID-19 pandemic, a wide spectrum of mucocutaneous findings was identified. Despite their protean and transient nature, these mucocutaneous features serve as important clues in the recognition of MIS-C.

OBJECTIVES/OBJECTIVE:To evaluate the outcomes of patients who underwent soft tissue flap coverage during treatment of a tibia fracture nonunion. DESIGN/METHODS:Retrospective analysis on prospectively collected data. SETTING/METHODS:Academic medical center. PATIENTS/PARTICIPANTS/METHODS:157 patients were treated for a fracture nonunion following a tibia fracture over a 15-year period. Sixty-six had sustained an open tibial fracture initially and 25 of these patients underwent soft tissue flaps for their open tibia fracture nonunion. INTERVENTION/METHODS:Manipulation of soft tissue flaps, either placement or elevation for graft placement in ununited previously open tibial fractures. MAIN OUTCOME MEASUREMENTS/METHODS:Bony healing, time to union, ultimate soft tissue status, postoperative complications, and functional outcome scores using the Short Musculoskeletal Functional Assessment (SMFA). This group was compared to a group of open tibial fracture nonunions that did not undergo soft tissue transfer. RESULTS:Bony healing was achieved in 24/25 patients (96.0%) who received flaps at a mean time to union of 8.7 ± 3.3 months compared to 39/41 patients (95.1%) at a mean 7.5 ± 3.2 months (p > 0.05) in the non-coverage group. Healing rate and time to union did not differ between groups. At latest follow-up, the flap coverage group reported a mean SMFA index of 17.1 compared to an SMFA index of 27.7 for the non-coverage group (p = 0.037). CONCLUSIONS:Utilization of soft tissue flaps in the setting of open tibia shaft nonunion repair surgery are associated with a high union rate (>90%). Coverage with or manipulation of soft tissue flaps did not result in improved bony healing rate or time to union compared to those who did not require flaps. However, soft tissue flap coverage was associated with higher functional scores at long-term follow-up. LEVEL OF EVIDENCE/METHODS:Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Cancer is a major public health problem and the second leading cause of death worldwide. The burden of cancer continues to grow and is projected to double by 2040. This situation calls for coordinated action and emphasizes the need to join efforts on worldwide initiatives, including World Cancer Research Day (WCRD), which aims to create and consolidate a yearly momentum to raise awareness and commitment for research on cancer. Cancer research is a key driver of advances in prevention and therapeutic strategies that will benefit tomorrow's cancer patients. In 2016, 10 international organizations partnered to launch the WCRD initiative. Five years later, a total of 89 organizations and more than half a million people have joined this global movement that helps raise awareness of the importance of cancer research, demonstrating that a collaborative research culture is essential to address current challenges and create opportunities to accelerate impactful cancer research for a better future.

BACKGROUND:Psoriasis is associated with increased cardiovascular risk that is not captured by traditional pro-inflammatory biomarkers. OBJECTIVE:To investigate the relationship between psoriasis area and severity index (PASI), circulating pro-inflammatory biomarkers, and vascular health in psoriasis. METHODS:In psoriasis and age, sex-matched controls, 273 proteins were analyzed utilizing the OLINK platform, while vascular endothelial inflammation and health was measured via direct transcriptomic analysis of brachial vein endothelial cells. RESULTS:= 48.18, p<0.001) in predicting vascular endothelial inflammation. LIMITATIONS/CONCLUSIONS:Our study was observational and does not allow for causal inference in the relationship between CCL20 and cardiovascular risk. CONCLUSION/CONCLUSIONS:We demonstrate that CCL20 expression has a strong association with vascular endothelial inflammation, reflects systemic inflammation, and may serve as a potential biomarker of impaired vascular health in psoriasis.