Hypocalcemia in combination with hyperphosphatemia impairs muscle cell differentiation in vitro.

PURPOSE: Hypoparathyroidism is a rare endocrine disorder characterized by low or absent secretion of parathyroid hormone (PTH), which leads to decreased calcium and increased phosphorus levels in the serum. The diagnosis of hypoparathyroidism is based on the identification of the aforementioned biochemical abnormalities, which may be accompanied by clinical manifestations. Symptoms of hypoparathyroidism, primarily attributed to hypocalcemia, include muscle cramps or spasms, facial, leg, and foot pain, seizures, and tingling in the lips or fingers. The treatment of hypoparathyroidism depends on the severity of symptoms and the underlying pathology. Over the long term, calcium supplements, active vitamin D analogs, and thiazide diuretics may be needed. In fact, in patient cohorts in which optimal disease control still remains elusive, replacement therapy with recombinant parathyroid hormone analogs may be contemplated. Despite the predominantly neuromuscular symptoms of hypoparathyroidism, further effects of parathyroid hormone deficiency at the muscle cell level remain poorly understood. Thus, the aim of our study was to evaluate the effects of hypocalcemia in combination with hyperphosphatemia on muscle cells differentiation in vitro. METHODS: C2C12 cells, an in vitro model of muscle cells, were differentiated for 2 or 6 days in the presence of hypocalcemia (CaCl2 0.9 mmol/l) and moderate (PO4 1.4 mmol/l) or severe (PO4 2.9 mmol/l) hyperphosphatemia, or combinations of both conditions. Cell differentiation and expression of genes linked to muscle differentiation were evaluated. RESULTS: The combination of hypocalcemia with hyperphosphatemia induced a significant reduction (50%) in differentiation marker levels, such as MyoD (protein 1 for myoblast determination) and myogenin on the 1st day of differentiation, and MHC (myosin heavy chains) after 6 days of differentiation compared to control. Furthermore, this condition induced a statistically significant reduction of insulin-like growth factor-1 (IGF-1) mRNA expression and inhibition of IGF signaling and decrease in ERK phosphorylation compared to control cells. CONCLUSIONS: Our results showed that a condition of hypocalcemia with hyperphosphatemia induced an alteration of muscle cell differentiation in vitro. In particular, we observed the reduction of myogenic differentiation markers, IGF-1 signaling pathway, and ERK phosphorylation in differentiated skeletal myoblasts. These data suggest that this altered extracellular condition might contribute to the mechanisms causing persistence of symptoms in patients affected by hypoparathyroidism.

Circulating miR-26b-5p and miR-451a as diagnostic biomarkers in medullary thyroid carcinoma patients.

PURPOSE/METHODS: The determination of tumour biomarkers is paramount to advancing personalized medicine, more so in rare tumours like medullary thyroid carcinoma (MTC), whose diagnosis is still challenging. The aim of this study was to identify non-invasive circulating biomarkers in MTC. To achieve this goal, paired MTC tissue and plasma extracellular vesicle samples were collected from multiple centres and microRNA (miRNA) expression levels were evaluated. RESULTS: The samples from a discovery cohort of 23 MTC patients were analysed using miRNA arrays. Lasso logistic regression analysis resulted in the identification of a set of circulating miRNAs as diagnostic biomarkers. Among them, miR-26b-5p and miR-451a, were highly expressed and their expression decreased during follow-up in disease-free patients in the discovery cohort. Circulating miR-26b-5p and miR-451a were validated using droplet digital PCR in a second independent cohort of 12 MTC patients. CONCLUSION: This study allowed the identification and validation of a signature of two circulating miRNAs, miR-26b-5p and miR-451a, in two independent cohorts reporting a significant diagnostic performance for MTC. The results of this study offer advancements in molecular diagnosis of MTC proposing a novel non-invasive tool to use in precision medicine.

Exploring disease perception in Behçet's syndrome: combining a quantitative and a qualitative study based on a narrative medicine approach.

BACKGROUND: Behçet Syndrome (BS) has a significant psychological and social impact on patients, caregivers and families. The present study aims at exploring disease perception in BS patients, using both a co-designed survey and the narrative medicine (NM) approach. METHODS: An ad-hoc questionnaire was co-designed by clinicians expert in BS, BS patients and caregivers and BS adult patients were invited to answer the online questionnaires. Cluster analysis was used to analyse data from the survey and to identify groups of patients with diverse disease perception. To further explore real-life perspectives, the stories of illness of a smaller group of adult BS patients were anonymously collected online and analysed by means of text, sentiment and qualitative analysis. RESULTS: Two hundred and seven patients answered the survey and forty-three stories were collected. The cluster analysis highlighted that accepting or not the disease has a strong impact on the daily life, on how BS patients perceive themselves and in terms of hope for the future. The stories revealed that patients often address common issues, such as the long and complex journey faced from the disease onset until the BS diagnosis, which was strongly connected to the concept of time and perceived as an exhausting period of their lives. CONCLUSION: To our knowledge, this is the first study that addressed disease perception also applying the NM principles in BS. The current perception that BS patients have of their disease should encourage the BS scientific and patient community in joining forces in order to improve the journey of BS patients.

Exploring the response of a key Mediterranean gorgonian to heat stress across biological and spatial scales.

Understanding the factors and processes that shape intra-specific sensitivity to heat stress is fundamental to better predicting the vulnerability of benthic species to climate change. Here, we investigate the response of a habitat-forming Mediterranean octocoral, the red gorgonian Paramuricea clavata (Risso, 1826) to thermal stress at multiple biological and geographical scales. Samples from eleven P. clavata populations inhabiting four localities separated by hundreds to more than 1500 km of coast and with contrasting thermal histories were exposed to a critical temperature threshold (25 °C) in a common garden experiment in aquaria. Ten of the 11 populations lacked thermotolerance to the experimental conditions provided (25 days at 25 °C), with 100% or almost 100% colony mortality by the end of the experiment. Furthermore, we found no significant association between local average thermal regimes nor recent thermal history (i.e., local water temperatures in the 3 months prior to the experiment) and population thermotolerance. Overall, our results suggest that local adaptation and/or acclimation to warmer conditions have a limited role in the response of P. clavata to thermal stress. The study also confirms the sensitivity of this species to warm temperatures across its distributional range and questions its adaptive capacity under ocean warming conditions. However, important inter-individual variation in thermotolerance was found within populations, particularly those exposed to the most severe prior marine heatwaves. These observations suggest that P. clavata could harbor adaptive potential to future warming acting on standing genetic variation (i.e., divergent selection) and/or environmentally-induced phenotypic variation (i.e., intra- and/or intergenerational plasticity).

MicroRNA loaded edible nanoparticles: an emerging personalized therapeutic approach for the treatment of obesity and metabolic disorders.

Obesity is a metabolic chronic disease whose prevalence is strongly growing in the last years, reaching pandemic proportions. Nowadays weight loss, achieved through lifestyle changes, is the first line therapeutic objective, although great inter-individual variabilities influence response to treatment, suggesting the involvement of epigenetic factors. In this contest, there is increasing recognition of the role of small RNA molecules, particularly microRNAs in the epigenetic regulation of genes involved in adipose tissue and glucose metabolism and several microRNAs have been found to be dysregulated in obesity and metabolic diseases. The development of novel personalized therapeutic strategies using microRNAs bears promise. However, the application of naked microRNAs has been hampered by their low specificity and sensitivity. In a recent issue of Theranostics, Kumar et al. explored the possibility of microRNA delivery through ginger-derived nanoparticles (GDNPs) as an alternative therapeutic approach for obesity treatment. The results reported by Kumar et al., addressing non-coding RNAs and edible plant derived nanoparticles, open new perspectives for the application of this innovative and safe delivery system in the clinical practice for the treatment of obesity and other metabolic disorders.

Low molecular weight heparin -induced miRNA changes in peripheral blood mononuclear cells in pregnancies with unexplained recurrent pregnancy loss.

Unexplained recurrent pregnancy loss (uRPL) is a clinical condition for which there is a lack of evidenced-based therapies. However, in clinical practice, low molecular weight heparin (LMWH) has been widely used as an empirical therapy since immune effects have been hypothesized in modulating immune tolerance at the fetal-maternal interface. Epigenetic mechanisms are involved in establishing of immune tolerance, at fetal-maternal interface. To investigate potential induced immune-epigenetic changes at maternal periphery level, which could reflect the maternal-fetal interface condition, seems to open up new therapeutical strategies, since microRNAs circulating in maternal plasma and in peripheral blood mononuclear cells (PBMCs) may be specific and sensitive immunological markers/predictors of adverse pregnancy outcomes such as RPL. Our aim in this pilot study is to evaluate potential LMWH effects on genes regulating immunological response key mechanisms related to maternal-fetal tolerance processes, by studying circulating miRNAs in maternal peripheral blood. We tested a panel of selected miRNAs on three groups: 18 healthy pregnant women, 20 pregnant women affected by uRPL, 18 pregnant women affected by uRPL, treated with LMWH. The majority of differentially expressed miRNAs (miR 374a-5p, 19a-3p, 30e-5p, 128-3p, 155-5p and 200c-3p) were found to be modulated by LMWH, which seems to have a positive function in RPL patients, by bringing patients' values back to those comparable to the control ones. Selected microRNA panels would appear to be an effective clinical tool for uRPL diagnosis and management. LMWH-modified miRNA expression levels could be targets for immunotherapy, as LMWH would appear to restore physiological miRNA levels, which are dysregulated in uRPL.

The endocrine disruptor cadmium: a new player in the pathophysiology of metabolic diseases.

Cadmium (Cd), a highly toxic heavy metal, is found in soil, environment and contaminated water and food. Moreover, Cd is used in various industrial activities, such as electroplating, batteries production, fertilizers, while an important non-occupational source is represented by cigarette smoking, as Cd deposits in tobacco leaves. Since many years it is clear a strong correlation between Cd body accumulation and incidence of many diseases. Indeed, acute exposure to Cd can cause inflammation and affect many organs such as kidneys and liver. Furthermore, the attention has focused on its activity as environmental pollutant and endocrine disruptor able to interfere with metabolic and energy balance of living beings. Both in vitro and in vivo experiments have demonstrated that the Cd-exposure is related to metabolic diseases such as obesity, diabetes and osteoporosis even if human studies are still controversial. Recent data show that Cd-exposure is associated with atherosclerosis, hypertension and endothelial damage that are responsible for cardiovascular diseases. Due to the large environmental diffusion of Cd, in this review, we summarize the current knowledge concerning the role of Cd in the incidence of metabolic and cardiovascular diseases.

Tissue and circulating microRNAs as biomarkers of response to obesity treatment strategies.

BACKGROUND: Obesity, characterized by an increased amount of adipose tissue, is a metabolic chronic alteration which has reached pandemic proportion. Lifestyle changes are the first line therapy for obesity and a large variety of dietary approaches have demonstrated efficacy in promoting weight loss and improving obesity-related metabolic alterations. Besides diet and physical activity, bariatric surgery might be an effective therapeutic strategy for morbid obese patients. Response to weight-loss interventions is characterised by high inter-individual variability, which might involve epigenetic factors. microRNAs have critical roles in metabolic processes and their dysregulated expression has been reported in obesity. AIM: The aim of this review is to provide a comprehensive overview of current studies evaluating changes in microRNA expression in obese patients undergoing lifestyle interventions or bariatric surgery. RESULTS: A considerable number of studies have reported a differential expression of circulating microRNAs before and after various dietary and bariatric surgery approaches, identifying several candidate biomarkers of response to weight loss. Significant changes in microRNA expression have been observed at a tissue level as well, with entirely different patterns between visceral and subcutaneous adipose tissue. Interestingly, relevant differences in microRNA expression have emerged between responders and non-responders to dietary or surgical interventions. A wide variety of dysregulated microRNA target pathways have also been identified, helping to understand the pathophysiological mechanisms underlying obesity and obesity-related metabolic diseases. CONCLUSIONS: Although further research is needed to draw firm conclusions, there is increasing evidence about microRNAs as potential biomarkers for weight loss and response to intervention strategies in obesity.

Chlamydia trachomatis elicits TLR3 expression but disrupts the inflammatory signaling down-modulating NFκB and IRF3 transcription factors in human Sertoli cells.

Chlamydia trachomatis, the leading cause of bacterial sexually transmitted diseases worldwide, can disseminate and localize to the upper genital tract impairing reproductive function. Specifically, ascending C. trachomatis genital infection has been demonstrated to cause epididymitis or epididymo-orchitis, well-known risk factors for male infertility. C. trachomatis possesses the ability to infect primary human Sertoli cells, key elements for the spermatogenetic process and the immune protection of germ cells. Therefore, herein, we investigated the innate immune response in Sertoli cells following C. trachomatis infection, as well as its indirect effects on human spermatozoa. Specifically, we evaluated C. trachomatis mediated induction of Toll-like Receptors (TLR) 2, 3 and 4 as well as of downstream intracellular signaling molecules (NFκB and IRF3) and the levels of the related inflammatory mediators (IL-1α, IL-6, IFN-α, IFN-ß and IFN-γ), in an in vitro infection model of primary human Sertoli cells. The main result of our study shows that C. trachomatis induced TLR3-mediated recognition in human Sertoli cells, accompanied by the down-modulation of NFκB and IRF3-dependent signaling pathways followed by no production of pro-inflammatory cytokines. In conclusion, our findings suggest that C. trachomatis can disrupt the innate immune response in Sertoli cells and evade intracellular killing, potentially giving rise to a long-term infection that may exert negative effects on the male reproductive system.

Enteric viruses, somatic coliphages and Vibrio species in marine bathing and non-bathing waters in Italy.

Microbial safety of recreational waters is a significant public health issue. In this study we assessed the occurrence and quantity of enteric viruses in bathing and non-bathing waters in Italy, in parallel with microbial faecal indicators, somatic coliphages and Vibrio spp. Enteric viruses (aichivirus, norovirus and enterovirus) were detected in 55% of bathing water samples, including samples with bacterial indicator concentrations compliant with the European bathing water Directive. Aichivirus was the most frequent and abundant virus. Adenovirus was detected only in non-bathing waters. Somatic coliphages were identified in 50% bathing water samples, 80% of which showed simultaneous presence of viruses. Vibrio species were ubiquitous, with 9 species identified, including potential pathogens (V. cholerae, V. parahaemoylticus and V. vulnificus). This is the first study showing the occurrence and high concentration of Aichivirus in bathing waters and provides original information, useful in view of a future revision of the European Directive.

Canonical and non-canonical adenosinergic pathways.

Adenosine (ADO) is an immunosuppressive molecule with multiple functions in different human organs. ADO is released through the concerted action of surface molecules endowed with enzymatic functions, that belong to two different adenosinergic pathways. The canonical pathway is started by CD39, that converts ATP to AMP. On the other hand, the non-canonical pathway metabolizes NAD+ to ADPR, through the action of CD38. The latter byproduct is then converted to AMP by CD203a/PC-1. Both pathways converge to CD73, that fully degrades AMP to the final product ADO. In this Review we take into account the most relevant finding regarding the expression of ectoenzymes belonging to both adenosinergic pathways in different cell types, including regulatory cell subsets and neoplastic cells. Moreover, we summarize the role of these molecules in different physiological and pathological settings. Finally, we discuss potential therapeutic application of specific inhibitors of ectoenzymes and/or ADO receptors.

Maternal and neonatal characteristics of a Canadian urban cohort receiving treatment for opioid use disorder during pregnancy.

The epidemic of prescription and non-prescription opioid misuse is of particular importance in pregnancy. The Society of Obstetricians and Gynaecologists of Canada currently recommends opioid replacement therapy with methadone or buprenorphine for opioid-dependent women during pregnancy. This vulnerable segment of the population has been shown to be at increased risk of blood-borne infectious diseases, nutritional insecurity and stress. The objective of this study was to describe an urban cohort of pregnant women on opioid replacement therapy and to evaluate potential effects on the fetus. A retrospective chart review of all women on opioid replacement therapy and their infants who delivered at The Ottawa Hospital General and Civic campuses between January 1, 2013 and March 24, 2017 was conducted. Data were collected on maternal characteristics, pregnancy outcomes, neonatal outcomes and corresponding placental pathology. Maternal comorbidities identified included high rates of infection, tobacco use and illicit substance use, as well as increased rates of placental abruption compared with national averages. Compared with national baseline averages, the mean neonatal birth weight was low, and the incidence of small for gestational age infants and congenital anomalies was high. The incidence of NAS was comparable with estimates from other studies of similar cohorts. Findings support existing literature that calls for a comprehensive interdisciplinary risk reduction approach including dietary, social, domestic, psychological and other supports to care for opioid-dependent women in pregnancy.

The miR-139-5p regulates proliferation of supratentorial paediatric low-grade gliomas by targeting the PI3K/AKT/mTORC1 signalling.

AIMS: Paediatric low-grade gliomas (pLGGs) are a heterogeneous group of brain tumours associated with a high overall survival: however, they are prone to recur and supratentorial lesions are difficult to resect, being associated with high percentage of disease recurrence. Our aim was to shed light on the biology of pLGGs. METHODS: We performed microRNA profiling on 45 fresh-frozen grade I tumour samples of various histological classes, resected from patients aged ≤16 years. We identified 93 microRNAs specifically dysregulated in tumours as compared to non-neoplastic brain tissue. Pathway analysis of the microRNAs signature revealed PI3K/AKT signalling as one of the centrally enriched oncogenic signalling. To date, activation of the PI3K/AKT pathway in pLGGs has been reported, although activation mechanisms have not been fully investigated yet. RESULTS: One of the most markedly down-regulated microRNAs in our supratentorial pLGGs cohort was miR-139-5p, whose targets include the gene encoding the PI3K's (phosphatidylinositol 3-kinase) catalytic unit, PIK3CA. We investigated the role of miR-139-5p in regulating PI3K/AKT signalling by the use of human cell cultures derived from supratentorial pLGGs. MiR-139-5p overexpression inhibited pLGG cell proliferation and decreased the phosphorylation of PI3K target AKT and phosphorylated-p70 S6 kinase (p-p70 S6K), a hallmark of PI3K/AKT/mTORC1 signalling activation. The effect of miR-139-5p was mediated by PI3K inhibition, as suggested by the decrease in proliferation and phosphorylation of AKT and p70 S6K after treatment with the direct PI3K inhibitor LY294002. CONCLUSIONS: These findings provide the first evidence that down-regulation of miR-139-5p in supratentorial pLGG drives cell proliferation by derepressing PI3K/AKT signalling.

Noncanonical GLI1 signaling promotes stemness features and in vivo growth in lung adenocarcinoma.

Aberrant Hedgehog/GLI signaling has been implicated in a diverse spectrum of human cancers, but its role in lung adenocarcinoma (LAC) is still under debate. We show that the downstream effector of the Hedgehog pathway, GLI1, is expressed in 76% of LACs, but in roughly half of these tumors, the canonical pathway activator, Smoothened, is expressed at low levels, possibly owing to epigenetic silencing. In LAC cells including the cancer stem cell compartment, we show that GLI1 is activated noncanonically by MAPK/ERK signaling. Different mechanisms can trigger the MAPK/ERK/GLI1 cascade including KRAS mutation and stimulation of NRP2 by VEGF produced by the cancer cells themselves in an autocrine loop or by stromal cells as paracrine cross talk. Suppression of GLI1, by silencing or drug-mediated, inhibits LAC cells proliferation, attenuates their stemness and increases their susceptibility to apoptosis in vitro and in vivo. These findings provide insight into the growth of LACs and point to GLI1 as a downstream effector for oncogenic pathways. Thus, strategies involving direct inhibition of GLI1 may be useful in the treatment of LACs.

New European Clinical Trial Regulation: perception and expectations in Italy.

BACKGROUND: In July 2012, the European Commission formalized the proposal for a European Clinical Trial Regulation that should replace the European Clinical Trials Directive 2001/20/CE. The new Regulation 536/2014 entered into force in June 2014 and it was expected to be applied not earlier than May 2016. Indeed, at the time, all required central tools are not yet available and new forecasts indicate it will become effective at the end of 2018. The aims of the Regulation are the promotion of higher standards in patient's safety and increasing transparency in Clinical Trials, also by changing the application process. METHODS: An online survey was conducted among the Italian's Clinical Research Coordinators and Clinical Investigators to examine the perception and knowledge about the upcoming changes in Clinical Trials. A total of 190 Clinical Research Coordinators and 80 Clinical Investigators were surveyed. RESULTS: Clinicians are less aware of the content of the Regulation than Clinical Research Coordinators, who demonstrate an extensive expertise on the topic (84.4%), mainly reached through self-training. The majority of the Investigators (74%) believes that their site's facilities and staff already met all the requirements imposed by the Regulation while Clinical Research Coordinators are less optimistic: 65.2% of them believes that the site staff is not yet fully aware of changes associated to its implementation. CONCLUSIONS: The general opinion of the interviewed is that the new Regulation will strongly affect the trial management regardless of their type and phase, and the fulfillment of the imposed requirements represents an opportunity that Italy should not miss to increase its attractiveness to the pharmaceutical market.

Water safety in healthcare facilities. The Vieste Charter.

The Study Group on Hospital Hygiene of the Italian Society of Hygiene, Preventive Medicine and Public Health (GISIO-SItI) and the Local Health Authority of Foggia, Apulia, Italy, after the National Convention "Safe water in healthcare facilities" held in Vieste-Pugnochiuso on 27-28 May 2016, present the "Vieste Charter", drawn up in collaboration with experts from the National Institute of Health and the Ministry of Health. This paper considers the risk factors that may affect the water safety in healthcare facilities and reports the current regulatory frameworks governing the management of installations and the quality of the water. The Authors promote a careful analysis of the risks that characterize the health facilities, for the control of which specific actions are recommended in various areas, including water safety plans; approval of treatments; healthcare facilities responsibility, installation and maintenance of facilities; multidisciplinary approach; education and research; regional and national coordination; communication.

Regulation of proapoptotic proteins Bak1 and p53 by miR-125b in an experimental model of Alzheimer's disease: Protective role of 17ß-estradiol.

Alzheimer's disease has become one of the most impacting disorders since world population is rapidly aging. MicroRNA-125b plays a crucial role in many cellular processes and pathologies, but, to date, its role in Alzheimer's disease is controversial. In this study, we demonstrated, for the first time, that the down regulation of miR-125b is a key event for the neurotoxic effect of Aß treatment in cortical neurons. Moreover, we found that 17ß-estradiol treatment protects neurons from the Aß-peptide induced neurotoxicity by increasing miR-125b expression that, in turn, decreased the expression, both at gene and protein levels, of the pro-apoptopic proteins Bak1 and p53. Overall, our data reveal miR-125b as a novel neuro-protector miRNA in Alzheimer's disease.

The interleukin (IL)-31/IL-31R axis contributes to tumor growth in human follicular lymphoma.

Interleukin (IL)-31A binds to an heterodimer composed of IL-31 receptor A (IL-31RA) and Oncostatin M Receptor (OSMR). The IL-31/IL-31R complex is involved in the pathogenesis of various skin diseases, including cutaneous T-cell lymphoma. No information is available on the relations between the IL-31/IL-31R complex and B-cell lymphoma. Here we have addressed this issue in follicular lymphoma (FL), a prototypic germinal center(GC)-derived B-cell malignancy. IL-31 enhanced primary FL cell proliferation through IL-31R-driven signal transducer and activator of transcription factor 1/3 (STAT1/3), extracellular signal-regulated kinase 1/2 (ERK1/2) and Akt phosphorylation. In contrast, GC B cells did not signal to IL-31 in spite of IL-31R expression. GC B cells expressed predominantly the inhibitory short IL-31RA isoform, whereas FL cells expressed predominantly the long signaling isoform. Moreover, GC B cells lacked expression of other IL-31RA isoforms potentially involved in the signaling pathway. IL-31 protein expression was significantly higher in surface membrane than in cytosol of both FL and GC B cells. IL-31 was detected in plasma membrane microvesicles from both cell types but not released in soluble form in culture supernatants. IL-31 and IL-31RA expression was higher in lymph nodes from FL patients with grade IIIa compared with grade I/II, suggesting a paracrine and/or autocrine role of IL-31/IL-31RA complex in tumor progression through microvesicle shedding.

Predicting factors for recurrence in low-grade Ta primary bladder tumours.

OBJECTIVES: Ta bladder tumors constitute 53% of primary bladder neoplasms, 70% of them being low-grade (G1). These tumors present a 15- 38% chance of recurrence during the first year. The aim of this paper is to identify the predicting factors of the first recurrence in a series of TaG1 primary bladder tumors. METHODS: We have retrospectively analyzed patients who were diagnosed with TaG1 primary bladder tumor by transurethral resection between 2004 and 2012. We established their tumor grade and pathological stage according to the WHO's classification guides for 1973 and 2004 as well as 2009's TNM. Those patients who were diagnosed before 2009 did not receive any adjuvant treatment. Those who were diagnosed later on received 40 mg of endovesical Mitomycin C during their immediate post operative period as their only treatment. We define recurrence as the presence of tumor after the first cystoscopy and relapse-free survival (RFS) as the period of time (in months) until the first recurrence appeared. Follow up constitutes the period of time (in months) until the last check-up or first recurrence. We also analyzed different variables: age, gender, smoking habits, muscular representation in the sample, size of the tumor (> or < 1 cm), multiple or single tumors and adjuvant treatment. The survival analysis was performed by the Kaplan-Meier method, using the long-rank test to evaluate the differences between groups. RESULTS: 68 patients were included in the study (73.5% men, 75% smokers). The average age was 61.9 years (the median being 58.5). Average follow up was 33.2 months (median 28.4). 35.3% of patients experienced recurrence. Average RFS was 19.2 ± 12.7 months (median 13.5). The majority of tumors were of a single nature (77.9%), with a size of less than 1 cm (55.9%) and with muscle representation (52.9%). 57.4% of patients did not receive adjuvant treatment. Only the absence of adjuvant treatment was associated with recurrence in uni and multivariate analysis (p<0,001), with a relative risk of 17,5 IC95% (7,6-30,2). CONCLUSION: The absence of adjuvant therapy with Mitomycin C is the only factor that, in a statistically significant way, increases the risk of recurrence, regardless of demographic factors and the characteristics of the tumor.