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Lymphedema (LD) is characterized by the accumulation of interstitial fluid, lipids and inflammatory cell infiltrate in the limb. Here, we find that LD tissues from women who developed LD after breast cancer exhibit an inflamed gene expression profile. Lipidomic analysis reveals decrease in specialized pro-resolving mediators (SPM) generated by the 15-lipoxygenase (15-LO) in LD. In mice, the loss of SPM is associated with an increase in apoptotic regulatory T (Treg) cell number. In addition, the selective depletion of 15-LO in the lymphatic endothelium induces an aggravation of LD that can be rescued by Treg cell adoptive transfer or ALOX15-expressing lentivector injections. Mechanistically, exogenous injections of the pro-resolving cytokine IFN−β restores both 15-LO expression and Treg cell number in a mouse model of LD. These results provide evidence that lymphatic 15-LO may represent a therapeutic target for LD by serving as a mediator of Treg cell populations to resolve inflammation.Specialised pro-resolving lipid mediators can reduce inflammatory responses and may be active in lymphedema. Here the authors show that in a mouse model 15-LO derived lipid mediators are reduced during inflammation and that a lack of the 15-LO producing enzyme aggravated disease and addition of 15-LO enzyme or Treg cells reduced disease. [ABSTRACT FROM AUTHOR]

Objective: Prospectively evaluate the impact of fluorodeoxyglucose-fluorine-18 positron emission tomography (FDG-PET) in the management of recurrence of advanced head and neck squamous cell carcinoma during the first year after treatment. Study Design: Seventy patients were followed-up every 6 to 8 weeks during the first year after initial combined curative therapy. FDG-PET, together with conventional imaging and endoscopy were performed systematically at 1 year (group A) or prompted earlier in case of clinically suspicious recurrence (group B). The referring physician evaluated the impact of FDG-PET on the patient's management. Another clinician checked the pertinence of decisions. Results: FDG-PET had a therapeutic impact in 8 of 43 group A patients and in 16 of 27 group B patients; the overall rate was 34%. This change was pertinent in 5 of 8 and 14 of 16 cases, respectively. Overall pertinence rate of decisions was 90% versus 70% without FDG-PET. Conclusions: FDG-PET had a significant overall therapeutic impact; the induced decisions were either pertinent or just led to "futile" noninvasive examinations. Systematic FDG-PET had a significantly lesser impact in comparison with FDG-PET motivated by clinical suspicion. [ABSTRACT FROM AUTHOR]

Objective: Coral reef atherosclerosis of the visceral aorta (CRA) is associated with renovascular hypertension (RVH), chronic mesenteric ischaemia (CMI), and malperfusion of the lower limbs. The outcomes of open surgery for this rare disease are described in this paper., Methods: This retrospective study included all patients who underwent open surgical repair of CRA at a single high volume referral centre between January 2009 and June 2023. The operation was preceded by pre-operative computed tomography angiography (CTA). Follow up was carried out to assess clinical improvement regarding walking, blood pressure control, and visceral and renal ischaemia. Post-operative survival and patency of the aorta and revascularised visceral arteries were evaluated by the Kaplan-Meier method., Results: Thirty eight patients, with a mean age of 65 years and predominantly women (57.9%), were included in the study. The surgical indication was RVH in 40.6%, CMI in 25%, and malperfusion of the lower limbs in 71.9% of patients. All procedures were performed by left lumbotomy, with re-implantation or visceral and or renal artery bypass in 15 patients (39.5%) and 17 (44.7%) cases of simultaneous infrarenal aortic revascularisation. One death (2.6%) secondary to acute mesenteric ischaemia occurred post-operatively. Three patients (7.9%) presented with myocardial infarction and 11 (28.9%) with post-operative acute kidney failure without haemodialysis. Median follow up was 32.5 months. Post-operatively, all patients with CMI and claudication became asymptomatic, and 17 (56.7%) showed improved hypertension. Six patients needed repeat visceral artery revascularisation. No CRA related death occurred during follow up. Survival rates were 91.9% and 61.6% at one and five years, respectively., Conclusion: Visceral aortic endarterectomy by left sided lumbotomy, preceded by multiplanar reconstruction CTA, is a safe and effective procedure for CRA, with low operative mortality and acceptable morbidity rates. Long term clinical monitoring by colour duplex scan or CTA is recommended due to a risk of re-stenosis of the endarterectomised visceral arteries., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Episodic mitochondrial myopathy with or without optic atrophy and reversible leukoencephalopathy (MEOAL) is a rare, orphan autosomal recessive disorder caused by mutations in ferredoxin-2 (FDX2), which is a [2Fe-2S] cluster-binding protein participating in the formation of iron-sulfur clusters in mitochondria. In this biosynthetic pathway, FDX2 works as electron donor to promote the assembly of both [2Fe-2S] and [4Fe-4S] clusters. A recently identified missense mutation of MEOAL is the homozygous mutation c.431C>T (p.P144L) described in six patients from two unrelated families. This mutation alters a highly conserved proline residue located in a loop of FDX2 that is distant from the [2Fe-2S] cluster. How this Pro to Leu substitution damages iron-sulfur cluster biosynthesis is unknown. In this work, we have first compared the structural, dynamic, cluster binding and redox properties of WT and P144L [2Fe-2S] FDX2 to have clues on how the pathogenic P144L mutation can perturb the FDX2 function. Then, we have investigated the interaction of both WT and P144L [2Fe-2S] FDX2 with its physiological electron donor, ferredoxin reductase FDXR, comparing their electron transfer efficiency and protein-protein recognition patterns. Overall, the data indicate that the pathogenic P144L mutation negatively affects the FDXR-dependent electron transfer pathway from NADPH to FDX2, thereby reducing the capacity of FDX2 in assembling both [2Fe-2S] and [4Fe-4S] clusters. Our study also provided solid molecular evidences on the functional role of the C-terminal tail of FDX2 in the electron transfer between FDX2 and FDXR., (© 2024 The Author(s). Protein Science published by Wiley Periodicals LLC on behalf of The Protein Society.)

Background: This phase II trial sought to be the first of its kind to estimate the success rate of endermology in reducing breast cancer-related lymphedema., Patients and Methods: ELOCS is a French, monocentric, randomized, open-label phase II trial. Patients were randomized to receive the following over a 5-day treatment period: standard intensive decongestant treatment (IDT) (bandages and manual lymphatic drainage MLD) (group 1); IDT including bandages, MLD, and Cellu M6 (group 2); and IDT including bandages and Cellu M6 (Group 3). The main endpoint was the success rate in each group, (reduction of at least 30% in the excess volume). We estimated that endermology treatment (groups 2 and 3) would be of interest successes occurred in at least 21 out of 31 patients., Results: A total of 93 patients were included (31 patients in each of the 3 groups). The median age was 64.5 years (IQR: [56.4-71.3]). Patients were treated with mastectomy (n = 35), axillary lymphadenectomy (n = 80), radiotherapy (n = 91), and chemotherapy (n = 68). The mean relative reduction in excess volume was 38% in group 1, 33% in group 2, and 34% in group 3. Success rate was 58.1% in group 1 (18/31, P = ,0237), 51.6% (16/31, P = ,5) in group 2, and 64.5% (20/31, P = ,075) in group 3. In the LPG groups (2 and 3), 10/62 (16%) patients found LPG painful and 9/62 (15%) patients considered it to be unpleasant., Conclusion: Even though the critical threshold of 21 successes was not met, this study was the first to validate a standardized and reproducible endermology protocol., Competing Interests: Disclosure The authors declare that there is no conflict of interest regarding the publication of this article. Publication is approved by all authors and the responsible authorities of the CHU Rangueil., (Copyright © 2024. Published by Elsevier Inc.)

Regulation of mRNA translation is a crucial step in controlling gene expression in stressed cells, impacting many pathologies, including heart ischemia. In recent years, ribosome heterogeneity has emerged as a key control mechanism driving the translation of subsets of mRNAs. In this study, we investigated variations in ribosome composition in human cardiomyocytes subjected to endoplasmic reticulum stress induced by tunicamycin treatment. Our findings demonstrate that this stress inhibits global translation in cardiomyocytes while activating internal ribosome entry site (IRES)-dependent translation. Analysis of translating ribosome composition in stressed and unstressed cardiomyocytes was conducted using mass spectrometry. We observed no significant changes in ribosomal protein composition, but several mitochondrial ribosomal proteins (MRPs) were identified in cytosolic polysomes, showing drastic variations between stressed and unstressed cells. The most notable increase in polysomes of stressed cells was observed in MRPS15. Its interaction with ribosomal proteins was confirmed by proximity ligation assay (PLA) and immunoprecipitation, suggesting its intrinsic role as a ribosomal component during stress. Knock-down or overexpression experiments of MRPS15 revealed its role as an activator of IRES-dependent translation. Furthermore, polysome profiling after immunoprecipitation with anti-MRPS15 antibody revealed that the "MRPS15 ribosome" is specialized in translating mRNAs involved in the unfolded protein response.

Long non-coding (lnc) RNAs, once considered as junk and useless, are now broadly recognized to have major functions in the cell. LncRNAs are defined as non-coding RNAs of more than 200 nucleotides, regulate all steps of gene expression. Their origin is diverse, they can arise from intronic, intergenic or overlapping region, in sense or antisense direction. LncRNAs are mainly described for their action on transcription, while their action at the translational level is more rarely cited. However, the bibliography in the field is more and more abundant. The present synopsis of lncRNAs involved in the control of translation reveals a wide field of regulation of gene expression, with at least nine distinct molecular mechanisms. Furthermore, it appears that all these lncRNAs are involved in various pathologies including cancer, cardiovascular and neurodegenerative diseases., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Secondary lymphedema (LD) corresponds to a severe lymphatic dysfunction leading to the accumulation of fluid and fibrotic adipose tissue in a limb. Here, we identified apelin (APLN) as a powerful molecule for regenerating lymphatic function in LD. We identified the loss of APLN expression in the lymphedematous arm compared to the normal arm in patients. The role of APLN in LD was confirmed in APLN knockout mice, in which LD is increased and associated with fibrosis and dermal backflow. This was reversed by intradermal injection of APLN-lentivectors. Mechanistically, APLN stimulates lymphatic endothelial cell gene expression and induces the binding of E2F8 transcription factor to the promoter of CCBE1 that controls VEGF-C processing. In addition, APLN induces Akt and eNOS pathways to stimulate lymphatic collector pumping. Our results show that APLN represents a novel partner for VEGF-C to restore lymphatic function in both initial and collecting vessels. As LD appears after cancer treatment, we validated the APLN-VEGF-C combination using a novel class of nonintegrative RNA delivery LentiFlash® vector that will be evaluated for phase I/IIa clinical trial., (© 2024. The Author(s).)

Circular RNAs (circRNAs) are a recently characterized family of gene transcripts forming a covalently closed loop of single-stranded RNA. The extent of their potential for fine-tuning gene expression is still being discovered. Several studies have implicated certain circular RNAs in pathophysiological processes within vascular endothelial cells and cancer cells independently. However, to date, no comparative study of circular RNA expression in different types of endothelial cells has been performed and analysed through the lens of their central role in vascular physiology and pathology. In this work, we analysed publicly available and original RNA sequencing datasets from arterial, veinous, and lymphatic endothelial cells to identify common and distinct circRNA expression profiles. We identified 4713 distinct circRNAs in the compared endothelial cell types, 95% of which originated from exons. Interestingly, the results show that the expression profile of circular RNAs is much more specific to each cell type than linear RNAs, and therefore appears to be more suitable for distinguishing between them. As a result, we have discovered a specific circRNA signature for each given endothelial cell type. Furthermore, we identified a specific endothelial cell circRNA signature that is composed four circRNAs: circCARD6, circPLXNA2, circCASC15 and circEPHB4. These circular RNAs are produced by genes that are related to endothelial cell migration pathways and cancer progression. More detailed studies of their functions could lead to a better understanding of the mechanisms involved in physiological and pathological (lymph)angiogenesis and might open new ways to tackle tumour spread through the vascular system.

Internal ribosome entry sites (IRESs) drive translation initiation during stress. In response to hypoxia, (lymph)angiogenic factors responsible for tissue revascularization in ischemic diseases are induced by the IRES-dependent mechanism. Here, we searched for IRES trans -acting factors (ITAFs) active in early hypoxia in mouse cardiomyocytes. Using knock-down and proteomics approaches, we show a link between a stressed-induced nuclear body, the paraspeckle, and IRES-dependent translation. Furthermore, smiFISH experiments demonstrate the recruitment of IRES-containing mRNA into paraspeckle during hypoxia. Our data reveal that the long non-coding RNA Neat1 , an essential paraspeckle component, is a key translational regulator, active on IRESs of (lymph)angiogenic and cardioprotective factor mRNAs. In addition, paraspeckle proteins p54 nrb and PSPC1 as well as nucleolin and RPS2, two p54 nrb -interacting proteins identified by mass spectrometry, are ITAFs for IRES subgroups. Paraspeckle thus appears as a platform to recruit IRES-containing mRNAs and possibly host IRESome assembly. Polysome PCR array shows that Neat1 isoforms regulate IRES-dependent translation and, more widely, translation of mRNAs involved in stress response., Competing Interests: AG, ER, FD, FH, FM, JA, FP, IA, EB, OB, CF, AH, PV, EL, FT, BG, AP No competing interests declared, (© 2022, Godet, Roussel et al.)

Stau1 is a pluripotent RNA-binding protein that is responsible for the post-transcriptional regulation of a multitude of transcripts. Here, we observed that lung cancer patients with a high Stau1 expression have a longer recurrence free survival. Strikingly, Stau1 did not impair cell proliferation in vitro, but rather cell migration and cell adhesion. In vivo, Stau1 depletion favored tumor progression and metastases development. In addition, Stau1 depletion strongly impaired vessel maturation. Among a panel of candidate genes, we specifically identified the mRNA encoding the cell adhesion molecule Thrombospondin 1 (THBS1) as a new target for Staufen-mediated mRNA decay. Altogether, our results suggest that regulation of THBS1 expression by Stau1 may be a key process involved in lung cancer progression.

The PI3K pathway is highly active in human cancers. The four class I isoforms of PI3K are activated by distinct mechanisms leading to a common downstream signaling. Their downstream redundancy is thought to be responsible for treatment failures of PI3K inhibitors. We challenged this concept, by mapping the differential phosphoproteome evolution in response to PI3K inhibitors with different isoform-selectivity patterns in pancreatic cancer, a disease currently without effective therapy. In this cancer, the PI3K signal was shown to control cell proliferation. We compared the effects of LY294002 that inhibit with equal potency all class I isoenzymes and downstream mTOR with the action of inhibitors with higher isoform selectivity toward PI3Kα, PI3Kβ, or PI3Kγ (namely, A66, TGX-221 and AS-252424). A bioinformatics global pathway analysis of phosphoproteomics data allowed us to identify common and specific signals activated by PI3K inhibitors supported by the biological data. AS-252424 was the most effective treatment and induced apoptotic pathway activation as well as the highest changes in global phosphorylation-regulated cell signal. However, AS-252424 treatment induced reactivation of Akt, therefore decreasing the treatment outcome on cell survival. Reversely, AS-252424 and A66 combination treatment prevented p-Akt reactivation and led to synergistic action in cell lines and patient organoids. The combination of clinically approved α-selective BYL-719 with γ-selective IPI-549 was more efficient than single-molecule treatment on xenograft growth. Mapping unique adaptive signaling responses to isoform-selective PI3K inhibition will help to design better combinative treatments that prevent the induction of selective compensatory signals., (©2021 American Association for Cancer Research.)

The lymphatic network of mammalian heart is an important regulator of interstitial fluid compartment and immune cell trafficking. We observed a remodeling of the cardiac lymphatic vessels and a reduced lymphatic efficiency during heart hypertrophy and failure induced by transverse aortic constriction. The lymphatic endothelial cell number of the failing hearts was positively correlated with cardiac function and with a subset of cardiac macrophages. This macrophage population distinguished by LYVE-1 (Lymphatic vessel endothelial hyaluronic acid receptor-1) and by resident macrophage gene expression signature, appeared not replenished by CCR2 mediated monocyte infiltration during pressure overload. Isolation of macrophage subpopulations showed that the LYVE-1 positive subset sustained in vitro and in vivo lymphangiogenesis through the expression of pro-lymphangiogenic factors. In contrast, the LYVE-1 negative macrophage subset strongly expressed MMP12 and decreased the endothelial LYVE-1 receptors in lymphatic endothelial cells, a feature of cardiac lymphatic remodeling in failing hearts. The treatment of mice with a CCR2 antagonist during pressure overload modified the proportion of macrophage subsets within the pathological heart and preserved lymphatic network from remodeling. This study reports unknown and differential functions of macrophage subpopulations in the regulation of cardiac lymphatic during pathological hypertrophy and may constitute a key mechanism underlying the progression of heart failure., (© 2021. The Author(s).)

In cancer, the lymphatic system is hijacked by tumor cells that escape from primary tumor and metastasize to the sentinel lymph nodes. Tumor lymphangiogenesis is stimulated by the vascular endothelial growth factors-C (VEGFC) after binding to its receptor VEGFR-3. However, how VEGFC cooperates with other molecules to promote lymphatics growth has not been fully determined. We showed that lymphangiogenesis developed in tumoral lesions and in surrounding adipose tissue (AT). Interestingly, lymphatic vessel density correlated with an increase in circulating free fatty acids (FFA) in the lymph from tumor-bearing mice. We showed that adipocyte-released FFA are uploaded by lymphatic endothelial cells (LEC) to stimulate their sprouting. Lipidomic analysis identified the monounsaturated oleic acid (OA) as the major circulating FFA in the lymph in a tumoral context. OA transporters FATP-3, -6 and CD36 were only upregulated on LEC in the presence of VEGFC showing a collaborative effect of these molecules. OA stimulates fatty acid β-oxidation in LECs, leading to increased AT lymphangiogenesis. Our results provide new insights on the dialogue between tumors and adipocytes via the lymphatic system and identify a key role for adipocyte-derived FFA in the promotion of lymphangiogenesis, revealing novel therapeutic opportunities for inhibitors of lymphangiogenesis in cancer.