MITO END-3: Efficacy of Avelumab immunotherapy according to molecular profiling in first-line endometrial cancer therapy.

BACKGROUND: Immunotherapy combined with chemotherapy significantly improves progression-free survival compared to first-line chemotherapy alone in advanced endometrial cancer, with a much larger effect size in microsatellite-instability high (MSI-H) cases. New biomarkers might help to select patients that may have benefit among those with a microsatellite-stable (MSS) tumor. METHODS: In a pre-planned translational analysis of the MITO END-3 trial, we assessed the significance of genomic abnormalities in patients randomized to standard carboplatin/paclitaxel without or with avelumab. RESULTS: Out of 125 randomized patients, 109 had samples eligible for next-generation sequencing (NGS) analysis, and 102 had MSI tested. According to The Cancer Genome Atlas (TCGA), there were 29 cases MSI-H, 26 MSS TP53 wild-type (wt), 47 MSS TP53 mutated (mut), and one case with POLE mutation. Four mutated genes were present in more than 30% of cases: TP53, PIK3CA, ARID1A, and PTEN. Eleven patients (10%) had a BRCA1/2 mutation (five in MSI-H and six in MSS). High TMB (≥10 Muts/Mb) was observed in all MSI-H patients, in four out of 47 MSS/TP53 mut, and no case in the MSS/TP53 wt category. The effect of avelumab on progression-free survival significantly varied according to TCGA categories, being favorable in MSI-H and worst in MSS/TP53 mut (P interaction=0.003); a similar non-significant trend was seen in survival analysis. ARID1A and PTEN also showed a statistically significant interaction with treatment effect, which was better in the presence of the mutation (ARID1A P interaction=0.01; PTEN P interaction=0.002). CONCLUSION: The MITO END-3 trial results suggest that TP53 mutation is associated with a poor effect of avelumab, while mutations of PTEN and ARID1A are related to a positive effect of the drug in patients with advanced endometrial cancer.

Early is Better: Report of a Cowden Syndrome.

In the clinical practice, it is not common for pediatricians to visit children with overgrowth phenotype. When it happens, it is important to focus on the age of manifestations and research the pathogenic causes using appropriate genetic test. Cowden syndrome is one of these rare causes; it is an autosomal dominant genodermatosis characterized by multiple hamartomas of ectodermal, mesodermal, and endodermal origin. It is caused by loss of function mutations in the phosphatase and tensin homolog (PTEN) gene located on chromosome 10q23.1 Loss of function of the PTEN gene contributes to overgrowth and risk for a variety of cancers including breast, thyroid, endometrium, skin, kidneys, and colon. The early diagnosis of Cowden disease allows a careful monitoring of the patients who are facing the risk of cancer transformation, which is the principal complication of the condition.

Antiviral effect of high-pressure nasal stimulation.

OBJECTIVE: In a previous study, we reported an increase of nasal nerve growth factor (NGF) in patients treated with high-pressure administration of sterile saline isotonic solution (HPpSIS). Herein we characterized the nasal mucosa in terms of innate immune response and cytokine signature, including antiviral properties. Potential NGF and antiviral benefits of HPpSIS were also discussed. PATIENTS AND METHODS: Twenty (20) patients (11 males, 9 females; age range 30-75 years old) underwent HPpSIS and nasal samples were collected before and after treatment. Nasal scraping was used for morphological (smears and Quick May-Grunwald Giemsa staining, MGG), biochemical (Histamine, Serotonin; ELISA) and molecular (messenger RNA, mRNA) analyses. Amplification of transcripts specific for Toll-like receptor (TLR) 3 (TLR3), TLR7, TLR9, Interleukin-(IL) 18 (IL18), IL13, IL12, eosinophil-derived neurotoxin (EDN), Eosinophil Cationic Protein (ECP), γ Interferon (γIFN), tryptase and serotonin was performed using the 2-step real-time Reverse Transcription Polymerase Chain Reaction (RT-PCR). Clinical and laboratory data were analyzed and compared. RESULTS: The clinical evaluation showed a protective effect of our therapy. Smears showed the presence of leucocytes, eosinophils (EOs) and mast cells (MCs), and increased immunoreactivity for ECP/RNase3 and EDN after HPpSIS. ELISA showed increased levels of Serotonin and EDN associated with unchanged levels of substance P(SP) and histamine. Increased eosinophil-derived neurotoxin eosinophil-derived neurotoxin (EDN) levels were confirmed by in situ fluorescent analysis. HPpSIS induced the upregulation of TLR3, TLR7 and TLR9 transcripts, while no changes were observed for Intercellular Adhesion Molecule 1 (ICAM1), IL18, Interleukin-15 (IL15) and IL12 transcripts nor for Interleukin-6 (IL6) and IL13. No changes were also observed for γIFN and EDN/RNase2 transcripts, while ECP/RNase3 transcripts were significantly upregulated after HPpSIS. Finally, tryptase transcripts were unchanged while serotonin transcripts were significantly increased after HPpSIS. CONCLUSIONS: The clinical and biomolecular changes observed at the nasal mucosa due to HpSS treatment suggest the activation of an innate surveillance, by means of TLR transcription, and a possible anti-viral response due to EDN upregulation. It remains to be verified if NGF, known to be released locally upon HpSIS treatment, might in part be responsible for this local activation.

Functional assessment in endometrial and cervical cancer: diffusion and perfusion, two captivating tools for radiologists.

Uterine cervical and endometrial cancers are two major gynecological malignancies, affecting women's health worldwide. Magnetic resonance imaging (MRI) is appropriate for evaluating malignant disease, thanks to the excellent soft tissue contrast and multiplanar imaging ability. Recently, functional MR techniques, namely diffusion-weighted imaging (DWI) and dynamic contrast-enhanced imaging (DCE), have proved to be a precious support not only in cancer diagnosis but also in disease staging, in the therapy planning, in monitoring response to treatment and during long-term recurrence surveillance. In the field of gynecologic oncology, the European Society of Urogenital Radiology (ESUR) recommends DWI and dynamic contrast-enhanced imaging (DCE-MRI) for local staging of endometrial and cervical cancer, but the potential application of functional imaging in all different aspects of patient management seems very promising. The aim of this article is to summarize the existing literature, providing a comprehensive update on the role of functional MRI in endometrial and cervical cancer.

Correlation between physical activity, nutritional intake, and osteoporosis in postmenopausal women: a preliminary evaluation.

OBJECTIVE: Osteoporosis is a chronic metabolic syndrome associated with debilitating consequences that represents one of the major non-communicable diseases and the most common bone illness that affects both men and women. This observational study evaluates the amount of physical activity and the nutritional intake in a group of postmenopausal women who have a sedentary job. PATIENTS AND METHODS: All subjects underwent a medical evaluation, a body impedance analysis to evaluate body composition (fat mass, fat-free mass, and body cell mass), and a dual-energy X-ray absorptiometry to analyze bone mineral density. Additionally, a 3-day food record questionnaire and the International Physical Activity Questionnaire were administered respectively to evaluate patients' foods and beverages assumptions and the participants' Physical Activity levels. RESULTS: The study showed that most of the patients had a moderate activity level and inadequate calcium and vitamin D assumption compared to guidelines. CONCLUSIONS: The onset of osteoporosis seemed to be reduced at higher levels of leisure time, domestic, and transport activities, even in subjects who have a sedentary job and insufficient assumption of micronutrients.

International consensus on the initial diagnostic workup of cancer of unknown primary.

BACKGROUND: Although the incidence of Cancer of Unknown Primary (CUP) is estimated to be 1-2 % of all cancers worldwide, no international standards for diagnostic workup are yet established. Such an international guideline would facilitate international comparison, provide adequate incidence and survival rates, and ultimately improve care of patients with CUP. METHODS: Participants for a four round modified Delphi study were selected via a CUP literature search in PubMed and an international network of cancer researchers. A total of 90 CUP experts were invited, and 34 experts from 15 countries over four continents completed all Delphi survey rounds. FINDINGS: The Delphi procedure resulted in a multi-layer CUP classification for the diagnostic workup. Initial diagnostic workup should at least consist of history and physical examination, full blood count, analysis of serum markers, a biopsy of the most accessible lesion, a CT scan of chest/abdomen/pelvis, and immunohistochemical testing. Additionally, the expert panel agreed on the need of an ideal diagnostic lead time for CUP patients. There was no full consensus on the place in diagnostic workup of symptom-guided MRI or ultrasound, a PET/CT scan, targeted gene panels, immunohistochemical markers, and whole genome sequencing. INTERPRETATION: Consensus was reached on the contents of the first diagnostic layer of a multi-layer CUP classification. This is a first step towards full consensus on CUP diagnostics, that should also include supplementary and advanced diagnostics.

Sweat analysis with a wearable sensing platform based on laser-induced graphene.

The scientific community has shown increasing interest in laser scribing for the direct fabrication of conductive graphene-based tracks on different substrates. This can enable novel routes for the noninvasive analysis of biofluids (such as sweat or other noninvasive matrices), whose results can provide the rapid evaluation of a person's health status. Here, we present a wearable sensing platform based on laser induced graphene (LIG) porous electrodes scribed on a flexible polyimide sheet, which samples sweat through a paper sampler. The device is fully laser manufactured and features a two layer design with LIG-based vertical interconnect accesses. A detailed characterization of the LIG electrodes including pore size, surface groups, surface area in comparison to electroactive surface area, and the reduction behavior of different LIG types was performed. The bare LIG electrodes can detect the electrochemical oxidation of both uric acid and tyrosine. Further modification of the surface of the LIG working electrode with an indoaniline derivative [4-((4-aminophenyl)imino)-2,6-dimethoxycyclohexa-2,5-dien-1-one] enables the voltammetric measurement of pH with an almost ideal sensitivity and without interference from other analytes. Finally, electrochemical impedance spectroscopy was used to measure the concentrations of ions through the analysis of the sweat impedance. The device was successfully tested in a real case scenario, worn on the skin during a sports session. In vitro tests proved the non-cytotoxic effect of the device on the A549 cell line.

Radical Nephroureterectomy Tetrafecta: A Proposal Reporting Surgical Strategy Quality at Surgery.

Background: Standardized methods for reporting surgical quality have been described for all the major urological procedures apart from radical nephroureterectomy (RNU). Objective: To propose a tetrafecta criterion for assessing the quality of RNU based on a consensus panel within the Young Association of Urology (YAU) Urothelial Group, and to test the impact of this tetrafecta in a multicenter, large contemporary cohort of patients treated with RNU for upper tract urothelial carcinoma (UTUC). Design setting and participants: This was a retrospective analysis of 1765 patients with UTUC treated between 2000 and 2021. Outcome measurements and statistical analysis: We interviewed the YAU Urothelial Group to propose and score a list of items to be included in the "RNU-fecta." A ranking was generated for the criteria with the highest sum score. These criteria were applied to a large multicenter cohort of patients. Kaplan-Meier curves were built to evaluate differences in overall survival (OS) rates between groups, and a multivariable logistic regression model was used to find the predictors of achieving the RNU tetrafecta. Results and limitations: The criteria with the highest score included three surgical items such as negative soft tissue surgical margins, bladder cuff excision, lymph node dissection according to guideline recommendations, and one oncological item defined by the absence of any recurrence in ≤12 mo. These items formed the RNU tetrafecta. Within a median follow-up of 30 mo, 52.6% of patients achieved the RNU tetrafecta. The 5-yr OS rates were significantly higher for patients achieving tetrafecta than for their counterparts (76% vs 51%). Younger age, lower body mass index, and robotic approach were found to be independent predictors of tetrafecta achievement. Conversely, a higher Eastern Cooperative Oncology Group score, higher clinical stage, and bladder cancer history were inversely associated with tetrafecta. Conclusions: Herein, we present a "tetrafecta" composite endpoint that may serve as a potential tool to assess the overall quality of the RNU procedure. Pending external validation, this tool could allow a comparison between surgical series and may be useful for assessing the learning curve of the procedure as well as for evaluating the impact of new technologies in the field. Patient summary: In this study, a tetrafecta criterion was developed for assessing the surgical quality of radical nephroureterectomy in patients with upper tract urothelial carcinoma. Patients who achieved tetrafecta had higher 5-yr overall survival rates than those who did not.

Design and Assembly of Multilevel Transcriptional and Translational Regulators for Stringent Control of Gene Expression.

Precise control of gene expression is crucial when reprogramming the behavior of living cells. However, common inducible systems often lack the ability to stringently control gene expression due to the use of a single type of regulator that can be susceptible to unavoidable biomolecular fluctuations. In contrast, multilevel controllers (MLCs) employ several forms of regulation simultaneously to overcome this issue, ensuring a reduced basal expression while minimally affecting the maximum induced expression level that can be achieved. Here, we show how our publicly available genetic toolkit can be used to simplify the assembly of MLCs for the stringent control of gene expression. We demonstrate how new compatible parts can be designed and explain the rapid end-to-end assembly procedure.

Enhanced presence of serotonin in nasal cavity after autologous stimulation.

OBJECTIVE: Serotonin, which is a vasoactive amine, is an important neurotransmitter and is involved in many behavioral and psychological phenomena, such as pain, appetite, mood, and sleep. The primary purpose of our study was to investigate the effect of high-pressure administration of sterile physiological saline isotonic solution (HpPSIS) into nasal cavity and to determine the expression of the serotonin. PATIENTS AND METHODS: The study was made in two branches, the previous with 14 volunteers, the subsequent study with 40 patients with mild anxiety disorder. The middle third of the inferior turbinate epithelial cells on the right nostril was scraped using a sterile curette and indicated as (pre), then, a spray of sterilized isotonic solution at high pressure on the left nostril was delivered, and 5 minutes later a similar stimulation was delivered on the same nostril. The stimulation was made with a specific spray dispenser. The middle third of the inferior turbinate epithelial cells on the left nostril was scraped using a sterile curette and indicated as (post). Then, based on the first part of our study, we started the second part and gave a treatment on forty new patients with anxiety disorder. RESULTS: The results of these studies highlight the possibility of endogenous enhancement of serotonin by stimulation of mast cells. In the first part of the study, Serotonin significantly increased in protein extracts after treatment (64.35±5.33 vs. 10.97±2.17; unpaired two tailed t-test, t=9.8, df=24, p≤0.0001; F=6.035; DFn=12; DFd=12). In the second part of the study, in patients treated with HpPSIS, we observed improvement of mood, after one, two and three months, with a statistically significant reduction of DASS-21, while no reduction was observed in control patients, treated with normal pressure commercial spray. CONCLUSIONS: This pilot study showed that the topical treatment of HpPHIS increases serotonin levels in nasal cavity. The observation reported in this study opens the way to a new valid strategy to enhance the level of endogenous serotonin. We observed a significant improvement of ASI on patients during HpPHIS therapy.

Systematic review of the CUP trials characteristics and perspectives for next-generation studies.

BACKGROUND: Research on therapeutic strategies for patients with unknown primary cancer (CUP) has been underwhelming. This paper summarized and evaluated the CUP therapeutic research over the previous five years. Based on this evaluation, recommendations for clinical trial designs are made to improve the impact of CUP research on patients. METHODS: Published and ongoing research were evaluated. PubMed was searched from January 1, 2015, to November 1, 2021. The start date of 2015 was chosen to identify research published after ESMO issued new diagnostic and therapeutic guidelines. The US National Library of Medicine indexed ongoing clinical trials. FINDINGS: Of the 244 CUP studies indexed in PubMed, 11.9% were prospective studies, and 4.9% were clinical trials. The review protocol deemed 65 publications eligible for full-text review. Eleven studies evaluating therapeutic regimens were retained. The two prospective studies and non-randomized trials showed promising outcomes for site-specific treatments. Randomized clinical trials were less promising; however, the trials had recruitment challenges resulting in biased accrual and the inability to keep pace with advancing diagnostics and therapeutics. Most of the 35 ongoing studies were phase II single-arm trials assessing immune checkpoint inhibitors (ICI) or site-specific therapies among CUP patients with suspected favorable prognoses. CONCLUSION: Our evaluation suggests two prospective clinical trial designs that addressed recent study design and recruitment challenges. A visionary approach uses a multi-arm, multistage randomized trial to address rapid advancements in diagnosis and therapy. A pragmatic approach utilizes a single-arm trial with historical controls to overcome comparison group and recruitment challenges.

Ethical issues in neurocritical care.

Medicine has always tried to push the limits of life. The technological and scientific progress made in resuscitation now makes it possible to keep patients who are more and more severely affected alive, by compensating for organ failure. The management of the brain-damaged patient poses specific ethical problems in intensive care. Most in-hospital deaths of patients with severe acute brain injury occur after a decision to withhold or withdraw life-sustaining treatments. In these patients, a problem is the difficulty in predicting outcome at an early stage. Our reasoning in the management of brain-damaged patients in the intensive care is based on the four main principles of medical ethics: autonomy, beneficence, non-maleficence and distributive justice. In the case of a patient suffering from cerebral palsy, consent is most often impossible to obtain. The respect of this autonomy, can be done by means of advance directives or testimonies of the support person and family. Non-malficence in the resuscitated brain-damaged patient consists of avoiding unreasonable obstinacy. Medical futility means that the proposed therapy should not be performed because available data show that it will not improve the patient's medical condition. A determination of medical futility can be made either in the presence of a vanishingly small probability of physiological effect or an exceedingly poor quality of outcome. However, a distinction must be made between loss of autonomy and unreasonable obstinacy. French law specifies that the physician must use collegial procedure in situations that may concern a brain-damaged patient. In terms of ethical decision-making, the concept of "window of opportunity" is often mentioned. The temporal approach taken is the guarantee of an absence of "a rush". It is important for the health care team and the family to share the progress of the treatment so that everyone understands the evolution of what is happening and the risks taken for the patient. The resuscitation of the brain-damaged patient poses specific and difficult ethical problems. One of the challenges is to be able to assume our decisions, understand them and defend them. It is also to maintain the coherence of our actions and the cohesion of our teams necessary for the good care of our patients.

Gray matter heterotopia: clinical and neuroimaging report on 22 children.

OBJECTIVE: To investigate the clinical characteristics and neuroimaging features of childhood presenting with gray matter heterotopia observed in a single tertiary Pediatric Department in Catania and compare the data with those reported in the literature. METHODS: A retrospectively review of the history, clinical findings, electrophysiological features and magnetic resonance images of 22 children presenting with gray matter heterotopia observed from January 2010 to January 2020. RESULTS: Among the 22 children included in the study, 17 presented with periventricular heterotopia (PVNH), two with Subcortical Band Heterotopia (SBH), and three with other subcortical heterotopia (SUBH). In the affected children, the ages at first diagnosis ranged from 3 months to 16 years with a mean age of 8.2 years (± 5.4); twelve (54.5%) suffered by developmental delay and intellectual deficit; eleven children (50%) complained of epileptic seizures, mostly focal to bilateral tonic-clonic seizure. In addition, in the periventricular heterotopia group (PVNH), cerebral and systemic malformations were reported in twelve (70%) and in ten (58%) children, respectively, out of seventeen. In the SBH plus SUBH group, epileptic seizures were recorded in 3 (60%) out of 5 children, cerebral malformations in one child and systemic malformations in two children. CONCLUSIONS: Heterotopic gray matter malformations include a group of disorders that manifest with a variety of neurological implications, such as cognitive impairment and epilepsy, and often related with epilepsy, other cerebral malformations and systemic anomalies.

Development and Validation of a Novel Nomogram for Individualized Prediction of Survival in Cancer of Unknown Primary.

PURPOSE: Prognostic uncertainty is a major challenge for cancer of unknown primary (CUP). Current models limit a meaningful patient-provider dialogue. We aimed to establish a nomogram for predicting overall survival (OS) in CUP based on robust clinicopathologic prognostic factors. EXPERIMENTAL DESIGN: We evaluated 521 patients with CUP at MD Anderson Cancer Center (MDACC; Houston, TX; 2012-2016). Baseline variables were analyzed using Cox regression and nomogram developed using significant predictors. Predictive accuracy and discriminatory performance were assessed by calibration curves, concordance probability estimate (CPE ± SE), and concordance statistic (C-index). The model was subjected to bootstrapping and multi-institutional external validations using two independent CUP cohorts: V1 [MDACC (2017), N = 103] and V2 (BC Cancer, Vancouver, Canada and Sarah Cannon Cancer Center/Tennessee Oncology, Nashville, TN; N = 302). RESULTS: Baseline characteristics of entire cohort (N = 926) included: median age (63 years), women (51%), Eastern Cooperative Oncology Group performance status (ECOG PS) 0-1 (64%), adenocarcinomas (52%), ≥3 sites of metastases (30%), and median follow-up duration and OS of 40.1 and 14.7 months, respectively. Five independent prognostic factors were identified: gender, ECOG PS, histology, number of metastatic sites, and neutrophil-lymphocyte ratio. The resulting model predicted OS with CPE of 0.69 [SE: ± 0.01; C-index: 0.71 (95% confidence interval: 0.68-0.74)] outperforming Culine/Seve prognostic models (CPE: 0.59 ± 0.01). CPE for external validation cohorts V1 and V2 were 0.67 (± 0.02) and 0.70 (± 0.01), respectively. Calibration curves for 1-year OS showed strong agreement between nomogram prediction and actual observations in all cohorts. CONCLUSIONS: Our user-friendly CUP nomogram integrating commonly available baseline factors provides robust personalized prognostication which can aid clinical decision making and selection/stratification for clinical trials.

Harnessing the central dogma for stringent multi-level control of gene expression.

Strictly controlled inducible gene expression is crucial when engineering biological systems where even tiny amounts of a protein have a large impact on function or host cell viability. In these cases, leaky protein production must be avoided, but without affecting the achievable range of expression. Here, we demonstrate how the central dogma offers a simple solution to this challenge. By simultaneously regulating transcription and translation, we show how basal expression of an inducible system can be reduced, with little impact on the maximum expression rate. Using this approach, we create several stringent expression systems displaying >1000-fold change in their output after induction and show how multi-level regulation can suppress transcriptional noise and create digital-like switches between 'on' and 'off' states. These tools will aid those working with toxic genes or requiring precise regulation and propagation of cellular signals, plus illustrate the value of more diverse regulatory designs for synthetic biology.

Improving dose delivery accuracy with EPID in vivo dosimetry: results from a multicenter study.

PURPOSE: To investigate critical aspects and effectiveness of in vivo dosimetry (IVD) tests obtained by an electronic portal imaging device (EPID) in a multicenter and multisystem context. MATERIALS AND METHODS: Eight centers with three commercial systems-SoftDiso (SD, Best Medical Italy, Chianciano, Italy), Dosimetry Check (DC, Math Resolution, LCC), and PerFRACTION (PF, Sun Nuclear Corporation, SNC, Melbourne, FL)-collected IVD results for a total of 2002 patients and 32,276 tests. Data are summarized for IVD software, radiotherapy technique, and anatomical site. Every center reported the number of patients and tests analyzed, and the percentage of tests outside of the tolerance level (OTL%). OTL% was categorized as being due to incorrect patient setup, incorrect use of immobilization devices, incorrect dose computation, anatomical variations, and unknown causes. RESULTS: The three systems use different approaches and customized alert indices, based on local protocols. For Volumetric Modulated Arc Therapy (VMAT) treatments OTL% mean values were up to 8.9% for SD, 18.0% for DC, and 16.0% for PF. Errors due to "anatomical variations" for head and neck were up to 9.0% for SD and DC and 8.0% for PF systems, while for abdomen and pelvis/prostate treatments were up to 9%, 17.0%, and 9.0% for SD, DC, and PF, respectively. The comparison among techniques gave 3% for Stereotactic Body Radiation Therapy, 7.0% (range 4.7-8.9%) for VMAT, 10.4% (range 7.0-12.2%) for Intensity Modulated Radiation Therapy, and 13.2% (range 8.8-21.0%) for 3D Conformal Radiation Therapy. CONCLUSION: The results obtained with different IVD software and among centers were consistent and showed an acceptable homogeneity. EPID IVD was effective in intercepting important errors.

Association of mitochondrial DNA copy number with metabolic syndrome and type 2 diabetes in 14 176 individuals.

BACKGROUND: Mitochondria play an important role in cellular metabolism, and their dysfunction is postulated to be involved in metabolic disturbances. Mitochondrial DNA is present in multiple copies per cell. The quantification of mitochondrial DNA copy number (mtDNA-CN) might be used to assess mitochondrial dysfunction. OBJECTIVES: We aimed to investigate the cross-sectional association of mtDNA-CN with type 2 diabetes and the potential mediating role of metabolic syndrome. METHODS: We examined 4812 patients from the German Chronic Kidney Disease (GCKD) study and 9364 individuals from the Cooperative Health Research in South Tyrol (CHRIS) study. MtDNA-CN was measured in whole blood using a plasmid-normalized qPCR-based assay. RESULTS: In both studies, mtDNA-CN showed a significant correlation with most metabolic syndrome parameters: mtDNA-CN decreased with increasing number of metabolic syndrome components. Furthermore, individuals with low mtDNA-CN had significantly higher odds of metabolic syndrome (OR = 1.025; 95% CI = 1.011-1.039, P = 3.19 × 10-4 , for each decrease of 10 mtDNA copies) and type 2 diabetes (OR = 1.027; 95% CI = 1.012-1.041; P = 2.84 × 10-4 ) in a model adjusted for age, sex, smoking and kidney function in the meta-analysis of both studies. Mediation analysis revealed that the association of mtDNA-CN with type 2 diabetes was mainly mediated by waist circumference in the GCKD study (66%) and by several metabolic syndrome parameters, especially body mass index and triglycerides, in the CHRIS study (41%). CONCLUSIONS: Our data show an inverse association of mtDNA-CN with higher risk of metabolic syndrome and type 2 diabetes. A major part of the total effect of mtDNA-CN on type 2 diabetes is mediated by obesity parameters.