Neutrophil extracellular traps mediate cardiomyocyte ferroptosis via the Hippo-Yap pathway to exacerbate doxorubicin-induced cardiotoxicity.

Doxorubicin-induced cardiotoxicity (DIC), which is a cardiovascular complication, has become the foremost determinant of decreased quality of life and mortality among survivors of malignant tumors, in addition to recurrence and metastasis. The limited ability to accurately predict the occurrence and severity of doxorubicin-induced injury has greatly hindered the prevention of DIC, but reducing the dose to mitigate side effects may compromise the effective treatment of primary malignancies. This has posed a longstanding clinical challenge for oncologists and cardiologists. Ferroptosis in cardiomyocytes has been shown to be a pivotal mechanism underlying cardiac dysfunction in DIC. Ferroptosis is influenced by multiple factors. The innate immune response, as exemplified by neutrophil extracellular traps (NETs), may play a significant role in the regulation of ferroptosis. Therefore, the objective of this study was to investigate the involvement of NETs in doxorubicin-induced cardiomyocyte ferroptosis and elucidate their regulatory role. This study confirmed the presence of NETs in DIC in vivo. Furthermore, we demonstrated that depleting neutrophils effectively reduced the occurrence of doxorubicin-induced ferroptosis and myocardial injury in DIC. Additionally, our findings showed the pivotal role of high mobility group box 1 (HMGB1) as a critical molecule implicated in DIC and emphasized its involvement in the modulation of ferroptosis subsequent to NETs inhibition. Mechanistically, we obtained preliminary evidence suggesting that doxorubicin-induced NETs could modulate yes-associated protein (YAP) activity by releasing HMGB1, which subsequently bound to toll like receptor 4 (TLR4) on the cardiomyocyte membrane, thereby influencing cardiomyocyte ferroptosis in vitro. Our findings suggest that doxorubicin-induced NETs modulate cardiomyocyte ferroptosis via the HMGB1/TLR4/YAP axis, thereby contributing to myocardial injury. This study offers a novel approach for preventing and alleviating DIC by targeting alterations in the immune microenvironment.

Protective effect of low-intensity pulsed ultrasound on immune checkpoint inhibitor-related myocarditis via fine-tuning CD4+ T-cell differentiation.

PURPOSE: Immune checkpoint inhibitors (ICIs) have transformed traditional cancer treatments. Specifically, ICI-related myocarditis is an immune-related adverse event (irAE) with high mortality. ICIs activate CD4+ T-lymphocyte reprogramming, causing an imbalance between Th17 and Treg cell differentiation, ultimately leading to myocardial inflammatory damage. Low-intensity pulsed ultrasound (LIPUS) can limit inflammatory responses, with positive therapeutic effects across various cardiovascular inflammatory diseases; however, its role in the pathogenesis of ICI-related myocarditis and CD4+ T-cell dysfunction remains unclear. Accordingly, this study investigated whether LIPUS can alleviate ICI-related myocarditis inflammatory damage and, if so, aimed to elucidate the beneficial effects of LIPUS and its underlying molecular mechanisms. METHODS: An in vivo model of ICI-related myocarditis was obtained by intraperitonially injecting male A/J mice with an InVivoPlus anti-mouse PD-1 inhibitor. LIPUS treatment was performed via an ultrasound-guided application to the heart via the chest wall. The echocardiographic parameters were observed and cardiac function was assessed using an in vivo imaging system. The expression of core components of the HIPPO pathway was analyzed via western blotting. RESULTS: LIPUS treatment reduced cardiac immune responses and inflammatory cardiac injury. Further, LIPUS treatment alleviated the inflammatory response in mice with ICI-related myocarditis. Mechanistically, in the HIPPO pathway, the activation of Mst1-TAZ axis improved autoimmune inflammation by altering the interaction between the transcription factors FOXP3 and RORγt and regulating the differentiation of Treg and Th17 cells. CONCLUSION: LIPUS therapy was shown to reduce ICI-related myocarditis inflammatory damage and improve cardiac function, representing an exciting finding for irAEs treatment.

Two-dimensional speckle tracking echocardiography help identify breast cancer therapeutics-related cardiac dysfunction.

BACKGROUND: Cancer therapeutics-related cardiac dysfunction (CTRCD) from different chemotherapy strategies are underdetermined by echocardiography. As an imaging marker of subclinical cardiac dysfunction, two-dimensional speckle tracking echocardiography (2D-STE) may assist in identifying the impact patterns of different CTRCD. METHODS: A total of 67 consecutive patients with invasive ductal breast carcinoma who will undertake neoadjuvant chemotherapy were enrolled and grouped according to their different chemotherapy regimens based on their biopsy results. Group A included 34 patients who received anthracycline without trastuzumab, whereas Group B had 33 patients who received trastuzumab without anthracycline. Echocardiography was performed at three time-points, i.e., baseline (T0), cycle-2 (T2), and cycle-4 (T4) of chemotherapy. Conventional echocardiographic measurements and 2D-STE strain values, and myocardial work (MW) parameters, were compared between different groups at different time-points. RESULTS: The mean age had no statistical difference between the two groups. E/e' was the only conventional echocardiographic parameter that had variation in group A (P < 0.05). Compared with baseline, GLS in group A decreased at T2, and GCS decreased at T4 (P < 0.05). GLS and GCS in group B both decreased at T4 (P < 0.05). More patients in group A had a more than 15% fall of baseline GLS rather than GCS at T2 (P < 0.05), however, there was no difference of either GLS or GCS decline rate at T4 between the two groups. All the MW parameters in group A had variations overtime, whereas only GCW in group B (P < 0.05). CONCLUSION: Early subclinical myocardial dysfunction can be identified by 2D-STE in breast cancer patients with chemotherapy, and GLS provides profound value in demonstrating the temporal changes in early myocardial damage induced by anthracycline. LV contractility injury in patients with trastuzumab may be mild at first but increases in severity with exposure time as early as cycle-4. Awareness of these differences may help to stratify the prevention of late cardiovascular events caused by different CTRCDs. In addition, GCW may be the most sensitive myocardial work parameter of CTRCD.

Ultrasound characteristics of sclerosing adenosis mimicking breast carcinoma.

BACKGROUND: Sclerosing adenosis (SA) is a benign lesion with complicated pathological components and could mimic breast carcinoma in both clinical palpation and medical imaging findings. The present study was conducted to assess the value of ultrasound (US) characteristics in diagnosing SA and their differentiation from breast carcinoma. METHODS: We retrospectively reviewed the medical records of 305 women (347 lesions) with invasive ductal carcinoma (IDC) and 54 women with single SA lesion, who had breast excision between April 2016 and July 2018. US BI-RADS atlas and elastography were applied and their associated characteristics were compared between SA and IDC. RESULTS: The mean age of SA was younger than that of IDC (43.6 ± 7.4 vs 53.2 ± 10.3, P < 0.001). Compared to IDC, SA had more frequency of parallel orientation (94.44% vs 71.76%, P < 0.001) and circumscribed margin (48.15% vs 4.90%, P < 0.001), less frequency of irregular shape (64.81% vs 95.97%, P < 0.001), hypoechoic echotexture (88.89% vs 98.27%, P = 0.002), calcification (12.96% vs 55.04%, P < 0.001), and posterior acoustic changes (3.70% vs 53.89%, P < 0.001) or associated features (architectural distortion, 3.70% vs 59.65%, P < 0.001; duct changes, 18.52% vs 63.40%, P < 0.001). Vascularity absence was more common in SA compared to IDC (35.19% vs 6.63%, P < 0.001). And the elasticity score was lower in SA (2.38 ± 0.60 vs 3.91 ± 0.81, P < 0.001). After adjusting for age, we found spiculated margin, posterior shadowing, calcification, architectural distortion, and vascularity could independently identify the differences between these two entities. After involving elasticity score, the calcification and vascularity could still be independent indicators for differential diagnosis. CONCLUSION: Understanding SA imaging features will enable radiologists to communicate results to the referring physician consistently, which could benefit a reliable assessment and specific management recommendations. A systematic evaluation of the US BI-RADS atlas together with breast elastography may be a powerful tool to identify SA and differentiate it from breast cancer.

A functional radioreceptor assay of alpha-V-beta-3 (alphavbeta3) inhibitors in plasma: application as an ex vivo pharmacodynamic model.

Development of alphavbeta3-integrin inhibitors has been hampered by a lack of pharmacodynamic endpoints to identify doses that inhibit alphavbeta3 in vivo. To address this need, we developed an alphavbeta3 radioreceptor assay (RRA) that could be performed in 100% plasma. The RRA was based on 125I-echistatin binding to plate-immobilized alphavbeta3. Small molecule alphavbeta3 inhibitors efficiently competed echistatin binding to alphavbeta3 when the assay was carried out in buffer. However, when carried out in 100% plasma, the RRA revealed a 45 to >3000-fold loss in compound potencies. The losses in potency reflected, in part, the high plasma protein binding by the compounds examined. The RRA was adapted as an ex vivo pharmacodynamic model. Echistatin binding was measured in the presence of plasma harvested at timed intervals from rats dosed with select compounds. Using this pharmacodynamic model, compound and dose selection was optimized for further testing in models of corneal angiogenesis. Moderate anti-angiogenic activity was achieved when rats were dosed sufficient to achieve sustained (>50%) plasma inhibition through the trough interval. Thus, the RRA provided a simple technique to rank order compound potency in plasma, and could find general use as an ex vivo pharmacodynamic assay to select compounds and doses for preclinical and clinical proof-of-principle studies.