Impact of simultaneous heart procurement on outcomes of donation after circulatory death lung transplantation.

Donation after circulatory death (DCD) heart procurement is done using either direct procurement (DP) or thoracoabdominal normothermic machine perfusion (TA-NRP). Both approaches could impact lung transplant outcomes with combined heart and lung procurements from the same donor. The impact of such practice on DCD lung transplant remains unstudied. We performed a retrospective analysis using the United Network for Organ Sharing (UNOS) dataset, identifying DCD lung transplants where the donor also donated the heart (cardia lung donor [CD]). A cohort of noncardiac DCD lung donors (noncardiac lung donor [NCD]) from the same era, matched for donor and recipient characteristics, was used as a comparison group. Both immediate and long-term outcomes were examined. A subanalysis was performed comparing the distinct impact of DP or TA-NRP on DCD lung transplant outcomes. Overall graft survival did not significantly differ between CD and NCD. However, recipients in the CD group trended toward a lower P/F ratio at 72 hours (CD vs NCD: 284 vs 3190; P = .054). In the subanalysis, we identified 40 DP donors and 22 TA-NRP donors. We found the both cohorts had lower P/F ratio at 72 hours than the NCD control (P = .04). Overall, 1-year graft survival was equivalent among the TA-NRP, DP, and NCD cohorts.

Prophylactic effect of tissue flap in the prevention of bronchopleural fistula after surgery for lung cancer.

PURPOSE: Bronchopleural fistula (BPF) is a serious complication of lung resection. To avoid BPF, the bronchial stump/anastomotic site is often covered with a flap of surrounding tissue. One risk factor for BPF is radical lung resection after induction chemoradiotherapy for lung cancer. We retrospectively reviewed our database to elucidate the characteristics of tissue flaps that prevent BPF. METHODS: This retrospective study included 152 patients treated between 1999 and 2019. We examined the clinicopathological characteristics, including the type and thickness of the tissue flap used to cover the bronchial stump/anastomotic site, and postoperative complications, including BPF. RESULTS: BPF occurred in 5 patients (3.3%). All 5 patients had complications that could have affected delayed wound healing, such as pneumonia. The covering tissue flap thickness was significantly greater in patients without BPF than in those who developed BPF (p = 0.0290). Additionally, the tissue flap thickness was significantly greater than in those with BPF (p = 0.0077), even in high-risk patients who developed pneumonia or radiation pneumonitis on the operative side within 6 months postoperatively. CONCLUSION: Perioperative management is crucial to avoid complications affecting the healing of the bronchial stump/anastomotic site, and the covering tissue flap thickness may be an important factor in avoiding or minimizing BPF.

S100A8/A9 as a prognostic biomarker in lung transplantation.

OBJECTIVES: S100A8/A9 is a damage-associated molecule that augments systemic inflammation. However, its role in the acute phase after lung transplantation (LTx) remains elusive. This study aimed to determine S100A8/A9 levels after lung transplantation (LTx) and evaluate their impact on overall survival (OS) and chronic lung allograft dysfunction (CLAD)-free survival. METHODS: Sixty patients were enrolled in this study, and their plasma S100A8/A9 levels were measured on days 0, 1, 2, and 3 after LTx. The association of S100A8/A9 levels with OS and CLAD-free survival was assessed using univariate and multivariate Cox regression analyses. RESULTS: S100A8/A9 levels were elevated in a time-dependent manner until 3 days after LTx. Ischemic time was significantly longer in the high S100A8/9 group than in the low S100A8/A9 group (p = .017). Patients with high S100A8/A9 levels (> 2844 ng/mL) had worse prognosis (p = .031) and shorter CLAD-free survival (p = .045) in the Kaplan-Meier survival analysis than those with low levels. Furthermore, multivariate Cox regression analysis showed that high S100A8/A9 levels were a determinant of poor OS (hazard ratio [HR]: 3.7; 95% confidence interval [CI]: 1.2-12; p = .028) and poor CLAD-free survival (HR: 4.1; 95% CI: 1.1-15; p = .03). In patients with a low primary graft dysfunction grade (0-2), a high level of S100A8/A9 was also a poor prognostic factor. CONCLUSIONS: Our study provided novel insights into the role of S100A8/A9 as a prognostic biomarker and a potential therapeutic target for LTx.

Drug repositioning of tranilast to sensitize a cancer therapy by targeting cancer-associated fibroblast.

Cancer-associated fibroblasts (CAFs) are a major component of the tumor microenvironment that mediate resistance of cancer cells to anticancer drugs. Tranilast is an antiallergic drug that suppresses the release of cytokines from various inflammatory cells. In this study, we investigated the inhibitory effect of tranilast on the interactions between non-small cell lung cancer (NSCLC) cells and the CAFs in the tumor microenvironment. Three EGFR-mutant NSCLC cell lines, two KRAS-mutant cell lines, and three CAFs derived from NSCLC patients were used. To mimic the tumor microenvironment, the NSCLC cells were cocultured with the CAFs in vitro, and the molecular profiles and sensitivity to molecular targeted therapy were assessed. Crosstalk between NSCLC cells and CAFs induced multiple biological effects on the NSCLC cells both in vivo and in vitro, including activation of the STAT3 signaling pathway, promotion of xenograft tumor growth, induction of epithelial-mesenchymal transition (EMT), and acquisition of resistance to molecular-targeted therapy, including EGFR-mutant NSCLC cells to osimertinib and of KRAS-mutant NSCLC cells to selumetinib. Treatment with tranilast led to inhibition of IL-6 secretion from the CAFs, which, in turn, resulted in inhibition of CAF-induced phospho-STAT3 upregulation. Tranilast also inhibited CAF-induced EMT in the NSCLC cells. Finally, combined administration of tranilast with molecular-targeted therapy reversed the CAF-mediated resistance of the NSCLC cells to the molecular-targeted drugs, both in vitro and in vivo. Our results showed that combined administration of tranilast with molecular-targeted therapy is a possible new treatment strategy to overcome drug resistance caused by cancer-CAF interaction.

Inhibiting S100A8/A9 attenuates airway obstruction in a mouse model of heterotopic tracheal transplantation.

Although bronchiolitis obliterans syndrome (BOS) is a major cause of death after lung transplantation, an effective drug therapy for BOS has not yet developed. Here, we assessed the effectiveness of a neutralizing anti-S100 calcium binding protein (S100) A8/A9 antibody against BOS. A murine model of heterotopic tracheal transplantation was used. Mice were intraperitoneally administered control IgG or the S100A8/A9 antibody on day 0 and twice per week until they were sacrificed. Tissue sections were used to evaluate the obstruction ratio, epithelium-preservation ratio, α-smooth muscle actin (SMA)-positive myofibroblast infiltration, and luminal cell death. Quantitative reverse transcriptase-polymerase chain reaction analysis was performed to analyze the mRNA-expression levels of collagen, inflammatory cytokines, and chemokines on days 7, 14, and 21. The anti-S100A8/A9 antibody significantly improved the obstruction ratio and epithelium-preservation ratio, with less α-SMA-positive myofibroblast infiltration compared to the control group. Antibody treatment reduced the type-III collagen: type-I collagen gene-expression ratio. The antibody also significantly suppressed the number of dead cells in the graft lumen. The expression levels of tumor growth factor ß1 and C-C motif chemokine 2 on day 21, but not those of interleukin-1ß, interleukin-6, and tumor necrosis factor α, were significantly suppressed by S100A8/A9 antibody treatment. These findings suggest that S100A8/A9 may be a potential therapeutic target for BOS after lung transplantation.

Protective effects of anti-HMGB1 monoclonal antibody on lung ischemia reperfusion injury in mice.

During ischemia reperfusion (IR) injury, high mobility group box 1 (HMGB1), a chromatin binding protein, is released from necrotic cells and triggers inflammatory responses. We assessed the therapeutic effect of a neutralizing anti-HMGB1 monoclonal antibody (mAb) on lung IR injury. A murine hilar clamp model of IR was used, where mice were divided into sham and IR groups with intravenous administration of anti-HMGB 1 mAb or control mAb. We analyzed the effect of anti-HMGB1 mAb against IR injury by assessing lung oxygenation, lung injury score, neutrophil infiltration, expression of proinflammatory cytokines and chemokines, levels of mitogen-activated protein kinase (MAPK) signaling, and measurement of apoptotic cells. Anti-HMGB1 mAb significantly decreased the plasma level of HMGB1 elevated by IR. The severity of IR injury represented by oxygenation capacity, lung injury score, and neutrophil infiltration was significantly improved by anti-HMGB1 mAb treatment. The expression of proinflammatory factors, including IL-1ß, IL-6, IL-12, TNF-α, CXCL-1, and CXCL-2, and phosphorylation of p38 MAPK were both significantly reduced by anti-HMGB1 mAb treatment. Furthermore, anti-HMGB1 mAb treatment suppressed apoptosis, as determined through TUNEL assays. Overall, anti-HMGB1 mAb ameliorated lung IR injury by reducing inflammatory responses and apoptosis. Our findings indicate that anti-HMGB1 mAb has potential for use as a therapeutic to improve IR injury symptoms during lung transplantation.

YES1 activation induces acquired resistance to neratinib in HER2-amplified breast and lung cancers.

Molecular-targeted therapies directed against human epidermal growth factor receptor 2 (HER2) are evolving for various cancers. Neratinib is an irreversible pan-HER tyrosine kinase inhibitor and has been approved by the FDA as an effective drug for HER2-positive breast cancer. However, acquired resistance of various cancers to molecular-targeted drugs is an issue of clinical concern, and emergence of resistance to neratinib is also considered inevitable. In this study, we established various types of neratinib-resistant cell lines from HER2-amplified breast and lung cancer cell lines using several drug exposure conditions. We analyzed the mechanisms of emergence of the resistance in these cell lines and explored effective strategies to overcome the resistance. Our results revealed that amplification of YES1, which is a member of the SRC family, was amplified in two neratinib-resistant breast cancer cell lines and one lung cancer cell line. Knockdown of YES1 by siRNA and pharmacological inhibition of YES1 by dasatinib restored the sensitivity of the YES1-amplified cell lines to neratinib in vitro. Combined treatment with dasatinib and neratinib inhibited tumor growth in vivo. This combination also induced downregulation of signaling molecules such as HER2, AKT and MAPK. Our current results indicate that YES1 plays an important role in the emergence of resistance to HER2-targeted drugs, and that dasatinib enables such acquired resistance to neratinib to be overcome.

Overcoming epithelial-mesenchymal transition-mediated drug resistance with monensin-based combined therapy in non-small cell lung cancer.

BACKGROUND: The epithelial-mesenchymal transition (EMT) is a key process in tumor progression and metastasis and is also associated with drug resistance. Thus, controlling EMT status is a research of interest to conquer the malignant tumors. MATERIALS AND METHODS: A drug repositioning analysis of transcriptomic data from a public cell line database identified monensin, a widely used in veterinary medicine, as a candidate EMT inhibitor that suppresses the conversion of the EMT phenotype. Using TGF-ß-induced EMT cell line models, the effects of monensin on the EMT status and EMT-mediated drug resistance were assessed. RESULTS: TGF-ß treatment induced EMT in non-small cell lung cancer (NSCLC) cell lines and the EGFR-mutant NSCLC cell lines with TGF-ß-induced EMT acquired resistance to EGFR-tyrosine kinase inhibitor. The addition of monensin effectively suppressed the TGF-ß-induced-EMT conversion, and restored the growth inhibition and the induction of apoptosis by the EGFR-tyrosine kinase inhibitor. CONCLUSION: Our data suggested that combined therapy with monensin might be a useful strategy for preventing EMT-mediated acquired drug resistance.

Point-of-Care Ultrasound (POCUS)-Guided Management of Cardiogenic Shock in COVID-19 Fulminant Myocarditis With Combined Veno-Arterial Extracorporeal Membrane Oxygenation and Impella (ECPELLA): A Case Report.

The COVID-19 pandemic, which has been raging globally, has been reported to cause not only pneumonia but also various cardiovascular diseases. In particular, myocarditis poses a serious risk if it becomes severe. As a characteristic of myocardial damage in this disease, right ventricular dysfunction is frequently reported, and biventricular failure is not uncommon. In cases where cardiogenic shock occurs, ECPELLA, which combines veno-arterial extracorporeal membrane oxygenation and Impella, is used for management. Currently, in Japan, ECPELLA is the central treatment for severe biventricular failure in the acute phase. However, its management method has not been established. Weaning from ECPELLA requires the following three conditions: (1) improvement of left ventricular function; (2) improvement of right ventricular function; and (3) optimization of circulating plasma volume. However, since these conditions change moment by moment, frequent and detailed assessments are necessary. Nevertheless, considering the need for isolation due to COVID-19, there are limitations on the tests that can be performed. In this regard, point-of-care ultrasound (POCUS) allows repeated bedside evaluations while maintaining infection protection. We report that in the case of severe COVID-19-related myocarditis, the use of POCUS enabled the preservation of cardiac function and appropriate timing for weaning from ECPELLA.

A Single Atrial Extrastimulation Resetting His Bundle During Supraventricular Tachycardia to Differentiate Atrial Tachycardia.

BACKGROUND: Catheter ablation is the curative treatment for paroxysmal supraventricular tachycardia (SVT). However, atrial tachycardia (AT) diagnosis is often challenging, especially when SVT is terminated by pacing. OBJECTIVES: This study sought to develop a novel method for AT diagnosis. METHODS: A total of 147 SVTs including 28 ATs, 87 atrioventricular nodal re-entrant tachycardias, and 32 orthodromic reciprocating tachycardias were prospectively studied. Single atrial extrastimulation was performed at the proximal coronary sinus from a coupling interval 20 milliseconds shorter than the tachycardia cycle length and gradually decreased until the His bundle (HB) was first reset and further until the SVT was terminated. The response of the SVT during the first HB resetting and the termination pattern were examined. RESULTS: In 27 of 28 ATs, tachycardia was unaffected when HB resetting whereas, in atrioventricular nodal re-entrant tachycardias or orthodromic reciprocating tachycardias (non-AT), tachycardia was simultaneously reset when HB resetting or was terminated with an atrio-Hisian block. When the coupling interval was further shortened for cases in which tachycardia persisted, all 33 SVTs with tachycardia termination with atrio-Hisian block were non-ATs, whereas 5 ATs and 7 non-ATs were terminated with Hisian-atrial block. The sensitivity, specificity, and positive and negative predictive values of the pattern of tachycardia that was unaffected when HB resetting for AT diagnosis were 96%, 100%, 100%, and 99%, respectively. Those of the pattern of tachycardia termination with atrio-Hisian block for non-AT diagnosis were 92%, 100%, 100%, and 42%, respectively. CONCLUSIONS: Single atrial extrastimulation from the proximal coronary sinus during tachycardia was useful and effective for AT diagnosis.