Citations

Abstract Large cell carcinoma (LCC) is an aggressive lung cancer subtype with poor prognosis and no targeted therapies. We previously reported that tumor-associated fibroblasts (TAFs) derived from LCC tumors exhibit premature senescence, and coculture of pulmonary fibroblasts with LCC cell lines selectively induces fibroblast senescence, which in turn drives LCC cell growth and invasion. Here we report that MMP1 is overexpressed specifically in LCC cell lines. Notably, silencing MMP1 expression in LCC cancer cell lines using shRNA revealed that MMP1 expression by LCC cells is necessary for induction of fibroblast senescence in coculture experiments with normal pulmonary fibroblasts, as revealed by the analysis of a panel of standard senescence markers, including β-galactosidase (SA-βgal) staining, permanent growth arrest and expression of senescence-associated secretory factors. Injecting control (shScr) or shMMP1 LCC cells into immunodeficient nude mice revealed that tumor growth, tumor take and cancer cell dissemination to the lung were reduced in shMMP1 H460 tumors compared to control tumors. We also observed fewer senescent fibroblasts in tumors from shMMP1 H460 cells using Sentragor staining, which allows identification of senescent cells in paraffin embedded tissues. Moreover, we found that recombinant active MMP1 in combination with TGF-β1 were sufficient to induce normal fibroblast senescence. In terms of the potential underlying mechanisms, treatment with the antioxidant n-acetyl cysteine (NAC) significantly attenuated the increase in SA-βgal+ fibroblasts elicited by co-stimulation with rMMP1 and TGF-β1, and its corresponding conditioned medium elicited a significantly lower growth and invasion in LCC cancer cells, revealing the oxidative stress implication in fibroblast senescence induction and associated pro-tumorigenic secretome. In summary, our results establish a new role for MMP1 in cancer and support that LCC cells elicit a tumor-supporting niche through the aberrant secretion of MMP1 and TGF-β1 to induce senescence in adjacent fibroblasts. Furthermore, we implicate oxidative stress in MMP1/TGF-β1-induced TAF senescence and support a novel therapeutic strategy in LCC based on targeting senescent TAFs. Citation Format: Marta Gabasa, Evette S. Radisky, Rafael Ikemori, Giulia Bertolini, Marselina Arshakyan, Alexandra Hockla, Paula Duch, Ornella Rondinone, Alejandro Llorente, Maria Maqueda, Alexandre Perera, Noemí Reguart, Luca Roz, Derek C. Radisky, Jordi Alcaraz. MMP1 and TGF-β1 cooperate to drive tumor progression in large cell carcinoma of the lung through fibroblast senescence [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2515.

Background: Two-dimensional volumetric exercise stress echocardiography (ESE) provides an integrated view of left ventricular (LV) preload reserve through end-diastolic volume (EDV) and LV contractile reserve (LVCR) through end-systolic volume (ESV) changes. Purpose: To assess the dependence of cardiac reserve upon LVCR, EDV, and heart rate (HR) during ESE. Methods: We prospectively performed semi-supine bicycle or treadmill ESE in 1344 patients (age 59.8 ± 11.4 years; ejection fraction = 63 ± 8%) referred for known or suspected coronary artery disease. All patients had negative ESE by wall motion criteria. EDV and ESV were measured by biplane Simpson rule with 2-dimensional echocardiography. Cardiac index reserve was identified by peak-rest value. LVCR was the stress-rest ratio of force (systolic blood pressure by cuff sphygmomanometer/ESV, abnormal values ≤2.0). Preload reserve was defined by an increase in EDV. Cardiac index was calculated as stroke volume index * HR (by EKG). HR reserve (stress/rest ratio) <1.85 identified chronotropic incompetence. Results: Of the 1344 patients, 448 were in the lowest tertile of cardiac index reserve with stress. Of them, 303 (67.6%) achieved HR reserve <1.85; 252 (56.3%) had an abnormal LVCR and 341 (76.1%) a reduction of preload reserve, with 446 patients (99.6%) showing ≥1 abnormality. At binary logistic regression analysis, reduced preload reserve (odds ratio [OR]: 5.610; 95% confidence intervals [CI]: 4.025 to 7.821), chronotropic incompetence (OR: 3.923, 95% CI: 2.915 to 5.279), and abnormal LVCR (OR: 1.579; 95% CI: 1.105 to 2.259) were independently associated with lowest tertile of cardiac index reserve at peak stress. Conclusions: Heart rate assessment and volumetric echocardiography during ESE identify the heterogeneity of hemodynamic phenotypes of impaired chronotropic, preload or LVCR underlying a reduced cardiac reserve.

In the renal proximal tubule (PT), Na + /K + ‐ATPase (NKA) is exclusively located in the basolateral domain. Through its classic ATP‐dependent ion‐pumping function, NKA generates the Na + gradient that drives apical Na + reabsorption, mostly through Na + /H + exchanger (NHE3). Accordingly, activation of NKA‐mediated ion transport decreases natriuresis through activation of basolateral (NKA) and apical Na + reabsorption (NHE3). In contrast, pharmacological evidence suggests that activation of the more recently discovered NKA signaling function triggers a cellular redistribution of NKA and NHE3 that decreases transcellular Na + flux in cultured PT cells. To obtain genetic evidence of this NKA/Src mechanism in the PT and asses its physiological importance, we used a knockdown and rescue approach in pig renal epithelial cells (LLC‐PK1). Additionally, we genetically targeted NKA α1 in the mouse PT by crossing mice expressing a sodium glucose co‐transporter 2 promoter driven Cre transgene with Floxed NKA α1 mice (PTα1 ‐/‐ ). Knockdown of 90% of NKA α1 in PT LLC‐PK1 cells increased transepithelial 22 Na flux by 2‐fold, activated NHE3 (50% decrease in inhibitory phosphorylation), and increased basolateral Na + /HCO 3 ‐ cotransporter (NBCe1A) protein content. In the PTα1 ‐/‐ mouse (4‐month males and females in a 1:1 ratio), 70% decrease in PT NKA α1 expression decreased urine output (0.51±0.14 vs 1.57±0.21 mL/24h in PTα1 +/+ , p<0.001, n=16) and absolute Na + excretion (0.14±0.05 vs 0.36±0.05 mmol/24h in PTα1 +/+ , p<0.05, n=8) by 65%, without histological or functional evidence of renal injury. Those changes were driven by increased PT Na + reabsorption, as indicated by a 65% decrease in lithium clearance (4‐month males, 1344±220 vs 3932±697 mL/24h in PTα1 +/+ , p<0.001, n=12) with unchanged GFR. This hyper‐reabsorptive phenotype of PTα1 ‐/‐ mice was coupled to increased membrane abundance of NHE3 and NBCe1A, and rescued upon crossing with floxed NHE3 mice, consistent a NKA/NHE3‐dependent mechanism. A dismantlement of caveolar NKA/Src receptor complex and intracellular redistribution of pY418Src occurred in knockdown NKA α1 PT cells, and was also observed in the PTα1 ‐/‐ hypomorphic mouse. Rescue of PT cells with wild‐type but not Src signaling‐null NKA α1 restored NHE3 and NBCe1A to basal levels, indicative of a role for NKA/Src receptor function in the tonic inhibition of Na + transporters in the PT. Hence, NKA signaling exerts a tonic inhibition on Na + reabsorption by regulating key apical and basolateral Na + transporters. This action, which is lifted upon NKA genetic suppression in cells and in vivo , tonically counteracts NKA's ATP‐driven function of basolateral Na + reabsorption. Strikingly, NKA/Src signaling is not only physiologically relevant, it is functionally dominant over NKA ion‐pumping in the control of PT reabsorption. NKA signaling therefore provides a long sought‐after mechanism for the natriuretic action of endogenous NKA ligands such as cardiotonic steroids.

Abstract Diagnosis of interstitial lung disease (ILD) requires a multidisciplinary discussion approach that includes clinicians, radiologists, and pathologists. Surgical lung biopsy (SLB) is currently the recommended standard in obtaining pathologic specimens for patients with ILD requiring a tissue diagnosis. The increased diagnostic confidence and accuracy provided by microscopic pathology assessment of SLB specimens must be balanced with the associated risks in patients with ILD. This document was developed by the SLB Working Group of the Pulmonary Fibrosis Foundation, composed of a multidisciplinary group of ILD physicians, including pulmonologists, radiologists, pathologists, and thoracic surgeons. In this document, we present an up-to-date literature review of the indications, contraindications, risks, and alternatives to SLB in the diagnosis of fibrotic ILD; outline an integrated approach to the decision-making around SLB in the diagnosis of fibrotic ILD; and provide practical information to maximize the yield and safety of SLB.

AbstractIleocolic resection (ICR) is the most common surgical procedure in Crohn disease (CD). There are many surgical techniques for performing ICRs and subsequent anastomoses. Recurrence of CD after ICR is common, often clinically silent, and thus requires monitoring including periodic use of endoscopy to detect early active disease. There is emerging evidence that surgical approaches may influence CD recurrence. This review explores the various surgical considerations, the data behind each decision, and how these techniques influence subsequent endoscopic surveillance.

Opsoclonus myoclonus syndrome (OMS) is a rare immune-mediated paraneoplastic or para/-post-infectious syndrome characterized by “dancing” eye movements, myoclonus, and ataxia. Neuropsychiatric symptoms have also been reported. Without treatment, OMS may progress to further neurological impairment and even death. Autoimmune attack of CNS structures in OMS is most commonly mediated by anti-Ri (also known as ANNA2) IgG antibodies, with additional findings implicating antibodies targeting various neurotransmitter receptors. Prompt immunotherapy and neoplasm treatment may result in improvement. We report a novel association of Contactin-Associated Protein-Like 2 (Caspr2) antibodies occurring in association with paraneoplastic OMS. While breast cancer and small cell lung cancer (SCLC) are more commonly associated with OMS among adults, we characterize a novel association between Caspr2 antibody in a patient with mixed non-small cell and small cell lung carcinoma.