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Elevated levels of mitochondrial iron and reactive oxygen species (ROS) accompany the progression of diabetes, negatively impacting insulin production and secretion from pancreatic cells. In search for a tool to reduce mitochondrial iron and ROS levels, we arrived at a molecule that destabilizes the [2Fe-2S] clusters of NEET proteins (M1). Treatment of db/db diabetic mice with M1 improved hyperglycemia, without the weight gain observed with alternative treatments such as rosiglitazone. The molecular interactions of M1 with the NEET proteins mNT and NAF-1 were determined by X-crystallography. The possibility of controlling diabetes by molecules that destabilize the [2Fe–2S] clusters of NEET proteins, thereby reducing iron-mediated oxidative stress, opens a new route for managing metabolic aberration such as in diabetes. Marjault et al. report two crystal structures of a drug molecule bound to NEET proteins mNT and NAF-1 and the effects of this molecule on diabetic mice, suggesting an approach for reducing mitochondrial iron and ROS levels in diabetic patients. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to explore the long-term outcomes of mesangial proliferative lupus nephritis (LN class II) and the factors associated with its relapse and histological transformation in Chinese patients. Methods: 104 SLE patients with biopsy-proven LN class II were included and divided into proteinuria group (proteinuria ≥ 0.4 g/24 h, with or without microscopic hematuria) and hematuria group (microscopic hematuria with proteinuria < 0.4 g/24 h).Patients were treated with glucocorticoid alone (GC monotherapy) or GC in combination with other immunosuppressant (combination therapy). The rates of remission, relapse, histological transformation, end-stage renal disease (ESRD), adverse events, and risk factors related to the outcomes were analyzed. Results: During the median follow-up of 77.5 (IQR 58–116.5) months, all the 104 patients achieved remission. Relapse occurred in 69 cases (66.3%), of which 37 were of renal relapse (35.6%). Histological transformation was found in 14 of the 16 (87.5%) cases who received repeated renal biopsy after renal relapse. At the end of follow-up, 3 (2.9%) patients developed ESRD. There were no significant differences in the rates of relapse, histological transformation, adverse events and in the time from remission to relapse between the proteinuria group and the hematuria group. In contrast, the cumulative relapse rate in the GC monotherapy group was much higher than that in the combination group (P < 0.01). Adverse events occurred in 55 (57.3%) patients during follow-up. Conclusions: Patients with LN class II have high rates of relapse and renal histological transformation and need optimal maintenance therapy. Key Points: • The rates of relapse and histological transformation are high in patients with LN class II. • Patients with LN class II are suggested to receive combination therapy and consider repeat renal biopsy after renal relapse. [ABSTRACT FROM AUTHOR]

Purpose: Cumulative evidence suggests that the addition of platinum agents as neoadjuvant chemotherapy (NACT) could improve the pathologic complete response (pCR) rate in triple-negative breast cancer (TNBC). We aimed to develop a DNA homologous recombination (HR)-associated gene expression score to predict tumor sensitivity to platinum-based NACT in TNBC. Methods: A retrospective cohort of 127 patients who were diagnosed with TNBC and received platinum-based NACT in Fudan University Shanghai Cancer Center from 2012 to 2017 was included in this study. Using quantitative reverse transcription-polymerase chain reaction (qRT-PCR), the expression levels of eight HR-associated genes were analyzed from formalin-fixed paraffin-embedded core-needle biopsy samples obtained before NACT. A random forest model was built to estimate the weight of each gene expression level and clinicopathological factors. The training set was used to modulate parameters and select the best model. The performance of the final model was evaluated in the validation set. Results: A 4-gene (BRCA1, XRCC5, PARP1, and RAD51) scoring system was developed. TNBC patients with a higher score had a nearly fourfold likelihood of achieving pCR to platinum-based NACT compared with patients with a lower score [odds ratio (OR) = 3.878; P < 0.001]. At the cutoff value of − 2.644, the 4-gene scoring system showed high sensitivity in predicting pCR in the breast (93.0%) and pCR in the breast/axilla (91.8%), while at the cutoff value of − 1.969, the 4-gene score showed high specificity for pCR in the breast (85.7%) and pCR in the breast/axilla (80.8%). Conclusion: The qRT-PCR-based 4-gene score has the potential to predict pCR to platinum-based NACT in TNBC. [ABSTRACT FROM AUTHOR]

Papillary renal cell carcinoma (pRCC) is the most heterogenous renal cell carcinoma. Patient survival varies and no effective therapies for advanced pRCC exist. Histological and molecular characterization studies have highlighted the heterogeneity of pRCC tumours. Recent studies identified the proximal tubule (PT) cell as a cell-of-origin for pRCC. However, it remains elusive whether other pRCC subtypes have different cell-of-origin. Here, by obtaining genome-wide chromatin accessibility profiles of normal human kidney cells using single-cell transposase-accessible chromatin-sequencing and comparing the profiles with pRCC samples, we discover that besides PT cells, pRCC can also originate from kidney collecting duct principal cells. We show pRCCs with different cell-of-origin exhibit different molecular characteristics and clinical behaviors. Further, metabolic reprogramming appears to mediate the progression of pRCC to the advanced state. Here, our results suggest that determining cell-of-origin and monitoring origin-dependent metabolism could potentially be useful for early diagnosis and treatment of pRCC. The heterogeneity of cell-of-origin for papillary renal cell carcinoma (pRCC) remains unknown. Here, with single-cell ATAC-seq from normal human kidney cells and ATACseq profiles from pRCC samples, the authors show that pRCC can originate from kidney collecting duct principal cells and this subtype is associated with advanced pRCC. [ABSTRACT FROM AUTHOR]

The NEET proteins constitute a unique class of [2Fe–2S] proteins. The metal ions bind to three cysteines and one histidine. The proteins' clusters exist in two redox states; the oxidized protein (containing two FeIII ions) can transfer the cluster to apo-acceptor protein(s), while the reduced form (containing one ferrous ion) remains bound to the protein frame. Here, we perform in silico and in vitro studies on human NEET proteins in both reduced and oxidized forms. Quantum chemical calculations on all available human NEET proteins structures suggest that reducing the cluster weakens the Fe–NHis and Fe–SCys bonds, similar to what is seen in other Fe–S proteins (e.g., ferredoxin and Rieske protein). We further show that the extra electron in the [2Fe–2S]+ clusters of one of the NEET proteins (mNT) is localized on the His-bound iron ion, consistently with our previous spectroscopic studies. Kinetic measurements demonstrate that the mNT [2Fe–2S]+ is released only by an increase in temperature. Thus, the reduced state of human NEET proteins [2Fe–2S] cluster is kinetically inert. This previously unrecognized kinetic inertness of the reduced state, along with the reactivity of the oxidized state, is unique across all [2Fe–2S] proteins. Finally, using a coevolutionary analysis, along with molecular dynamics simulations, we provide insight on the observed allostery between the loop L2 and the cluster region. Specifically, we show that W75, R76, K78, K79, F82 and G85 in the latter region share similar allosteric characteristics in both redox states. [ABSTRACT FROM AUTHOR]

Objectives: Non-immune complex (IC)-mediated renal thrombotic microangiopathy (TMA) has been reported in patients with systemic lupus erythematosus (SLE), but most studies included patients with both renal TMA and IC-mediated lupus nephritis (LN). In this study, the clinicopathological features and outcomes of renal injury characterised by only renal TMA were retrospectively analyzed. Methods: Patients with glomerular and/or vascular TMA in the absence of subendothelial or epithelial immune deposits were screened from 2,332 biopsied of SLE patients. The TMA lesions were divided into glomerular, vascular or both. Acute tubular-interstitial injury was semi-quantitatively analyzed. The podocyte foot process effacement (FPE) was measured by electronic microscopy. Results: Two hundred fifty-seven (11.0%) renal biopsies revealed TMA, among which 237 biopsies showed TMA coexisting with LN, and 20 (0.9%) biopsies had only renal TMA without or with only mesangial immune deposits. All patients manifested with acute kidney injury and haematological disorders. Among them, 11 (55%) required renal replacement therapy, 12 (60%) had nephrotic syndrome and 13 (65.0%) showed microvascular haemolytic anaemia with thrombocytopenia. Seventeen (85%) biopsies revealed both glomerular TMA and vascular TMA, two had only glomerular TMA and one had vascular TMA. Eight (40%) had no glomerular immune deposits and 12 (60%) showed only mesangial immune deposits. The acute tubulointerstitial injury in patients requiring dialysis was more severe than those not needing dialysis ((43.6 ± 24.9) % vs. (21.7 ± 20.1) %, p = 0.047). FPE of podocytes was positively correlated with proteinuria (r2 = 0.347, p = 0.006). All patients received high-dose methylprednisolone pulse therapy. Four patients received plasma exchange. The renal function of 11 patients requiring dialysis initially recovered after 16.0 (interquartile range [IQR] 9.0, 30.0) days of treatment. During the follow-up of 58.0 (IQR 36.0, 92.3) months, remission was achieved in 19 (95%) patients; only one patient had no response. No patient died or progressed to end-stage renal disease; six patients (30%) relapsed. Conclusion: Renal TMA, usually accompanying severe renal injury, was not uncommon in SLE patients with renal disease and should be distinguished from immune complex–mediated severe classes of LN. Early intensive immunosuppressive treatment may be associated with a good long-term renal outcome. Key Points • Most previous reports of renal TMA in SLE patients were associated with severe types of immune complex–mediated lupus nephritis; • Renal TMA with glomerular pauci-immune or only mesangial immune deposits was found in SLE patients and clinically presented with severe acute renal injury but good renal outcome; • Renal TMA should be considered as a unique type of SLE-associated renal injury. [ABSTRACT FROM AUTHOR]

(C) Representative images of migrated CSCs induced by 100 ng/mL SDF-1 with or without CXCR4 siRNA or CXCR7 siRNA by transwell migration assay. 1: Medium alone group; 2: 100 ng/mL SDF-1 group; 3: CXCR4 siRNA group; 4: SDF-1 + CXCR4 siRNA group; 5: CXCR7 siRNA group; 6: SDF-1 + CXCR7 siRNA group. [Extracted from the article]

Matriptase is a type II transmembrane serine protease, which has been suggested to play critical roles in numerous pathways of biological developments. Matriptase is the activator of several oncogenic proteins, including urokinase-type plasminogen activator (uPA), hepatocyte growth factor (HGF) and protease-activated receptor 2 (PAR-2). The activations of these matriptase substrates subsequently lead to the generation of plasmin, matrix metalloproteases (MMPs), and the triggers for many other signaling pathways related to cancer proliferation and metastasis. Accordingly, matriptase is considered an emerging target for the treatments of cancer. Thus far, inhibitors of matriptase have been developed as potential anti-cancer agents, which include small-molecule inhibitors, peptide-based inhibitors, and monoclonal antibodies. This review covers established literature to summarize the chemical and biochemical aspects, especially the inhibitory mechanisms and structure-activity relationships (SARs) of matriptase inhibitors with the goal of proposing the strategies for their future developments in anti-cancer therapy. [ABSTRACT FROM AUTHOR]

Massively heterogeneous architectures are widely adopted for the design of modern peta-scale and future exa-scale systems. In such heterogeneous clusters, due to the increasing number of involved components, it is essential to enable fault tolerance to improve the reliability of the whole system. However, existing programming models for heterogeneous clusters (e.g., MPI + X) concern more on performance, instead of reliability. In this paper, we design and implement a fault tolerance framework for hybrid programs that leverage heterogeneous hardware architectures based on the in-memory checkpointing technique. We provide new capabilities for programming heterogeneous applications that can greatly simplify the implementation of application-level checkpointing. We also conduct optimizations on checkpoint saving and loading to increase scalability. We validate effectiveness of the framework with various benchmarks and real-world applications on the Tianhe-2 supercomputer. Our experimental results show that our framework can improve the resilience of long-running applications and reduce checkpointing overhead. [ABSTRACT FROM AUTHOR]

Stromal cell-derived factor 1 (SDF-1) is a chemokine that can be expressed in injured cardiomyocytes after myocardial infarction (MI). By combining with its receptor CXCR4, SDF-1 induced stem and progenitor cells migration. CXCR7, a novel receptor for SDF-1, has been identified recently. We aimed to explore the roles of SDF-1/CXCR4 and SDF-1/CXCR7 pathway and their crosstalk in CSCs migration. In the present study, CXCR4 and CXCR7 expression were identified in CSCs. Transwell assay showed that SDF-1 caused CSCs migration in a dose- and time-dependent manner, which could be significantly suppressed by CXCR4 or CXCR7 siRNA. Phospho-ERK, phospho-Akt and Raf-1 significantly elevated in CSCs with SDF-1 stimulation. Knockdown of CXCR4 or CXCR7 significantly decreased phospho-ERK or phospho-Akt, respectively, and eventually resulted in the inhibition of CSCs migration. Moreover, western blot showed that MK2206 (Akt inhibitor) increased the expression of phospho-ERK and Raf-1, whereas PD98059 (ERK inhibitor) had no effect on phospho-Akt and Raf-1. GW5074 (Raf-1 inhibitor) upregulated the expression of phospho-ERK, but had no effect on phospho-Akt. The present study indicated that SDF-1/CXCR7/Akt and SDF-1/CXCR4/ERK pathway played important roles in CSCs migration. Akt phosphorylation inhibited Raf-1 activity, which in turn dephosphorylated ERK and negatively regulated CSCs migration. [ABSTRACT FROM AUTHOR]