Systemic and nonrenal adverse effects occurring in renal transplant patients treated with mTOR inhibitors. Clin Dev Immunol. 2013;2013:403280. [PMID: 24151517 PMCID: PMC3789319 DOI: 10.1155/2013/403280]

Advances in targeted therapies for age-related osteoarthritis: A comprehensive review of current research

Osteoarthritis (OA) is a common degenerative joint disease that disproportionately impacts the elderly population on a global scale. As aging is a significant risk factor for OA, there is a growing urgency to develop specific therapies that target the underlying mechanisms of aging associated with this condition. This summary seeks to offer a thorough introduction of ongoing research efforts aimed at developing therapies to combat senescence in the context of OA. Cellular senescence plays a pivotal role in both the deterioration of cartilage integrity and the perpetuation of chronic inflammation and tissue remodeling. Consequently, targeting SnCs has emerged as a promising therapeutic approach to alleviate symptoms and hinder the progression of OA. This review examines a range of approaches, including senolytic drugs targeting SnCs, senomorphics that modulate the senescence-associated secretory phenotype (SASP), and interventions that enhance immune system clearance of SnCs. Novel methodologies, such as utilizing novel materials for exosome delivery and administering anti-aging medications with precision, offer promising avenues for the precise treatment of OA. Accumulating evidence underscores the potential of targeting senescence in OA management, potentially facilitating the development of more effective and personalized therapeutic interventions.

Oral Health in Children with Chronic Kidney Disease, Hemodialysis, and Renal Transplantation: A Comprehensive Narrative Review of the Oral Manifestations and Dental Implications

Chronic kidney disease (CKD) in children presents multifaceted challenges, impacting various aspects of health, including oral health. This narrative review provides a comprehensive synthesis of literature focusing on the oral health status of pediatric CKD patients, encompassing oral manifestations, dental considerations, and management challenges associated with hemodialysis and kidney transplantation. A comprehensive search strategy was employed, utilizing databases such as PubMed, Scopus, Web of Science, and Google Scholar, to identify relevant literature on oral manifestations in children with CKD, including those undergoing hemodialysis or renal transplantation. Search terms were carefully selected to capture studies examining enamel hypoplasia, dental caries, delayed tooth eruption, gingival diseases, periodontal diseases, radiographic alterations, craniofacial development, dry mouth, and changes in the oral mucosa. Our narrative review meticulously selected articles through a systematic process. Ultimately, 12 studies meeting the inclusion criteria were included in the review. Relevant data from each included study were independently extracted and synthesized, focusing on oral manifestations and their implications in pediatric CKD patients. The synthesized findings were organized and presented in a structured manner within the review article, considering their clinical implications and informing recommendations for dental management of children with CKD. This article highlights the importance of a coordinated effort between nephrologists, dentists, and other healthcare professionals in providing holistic care for pediatric CKD patients. A comprehensive understanding of the oral health status of these children, along with proactive dental management strategies, contributes to improved overall health outcomes and a better quality of life. This review aims to serve as a valuable resource for the oral healthcare providers involved in the care of pediatric CKD patients.

Calcineurin and mTOR inhibitors in kidney transplantation: integrative metamodeling on transplant survival and kidney function

In our study, we examined the efficacy of mTOR (mammalian target of rapamycin) inhibitors, specifically rapamycin (Rap), compared to calcineurin inhibitors (CNIs) in kidney transplantation. By conducting a comprehensive search across reputable databases (EMBASE, Scopus, PubMed, Cochrane, and Crossref), we gathered data for a six-month post-transplantation period. Our analysis revealed that mTOR inhibitor administration resulted in improved glomerular filtration rate (GFR) and serum creatinine levels. However, it is important to note that the mTOR inhibitor group had a higher incidence of acute rejection after biopsy. Through molecular modeling, we observed that Rap exhibited a superior binding affinity for mTOR compared to CNIs' binding to calcineurin, probably contributing to the transplant rejection. Our meta-analysis supports the cautious use of an optimal mTOR inhibitor in conjunction with careful consideration of clinical features when minimizing CNIs early in the transplantation process. This is because mTOR inhibitors have complementary mechanisms of action, a low nephrotoxicity profile, and favorable outcomes in serum creatinine and GFR, which contribute to improved transplant survival.

Targeting ageing with rapamycin and its derivatives in humans: a systematic review

Rapamycin and its derivatives (rapalogs) are inhibitors of mTOR, a major regulator of the ageing process. We aimed to summarise the effects of rapamycin and its derivatives on the severity of ageing-related physiological changes and disease in adults. A search across five databases yielded 18 400 unique articles, resulting in 19 included studies. Rapamycin and its derivatives improved physiological parameters associated with ageing in the immune, cardiovascular, and integumentary systems of healthy individuals or individuals with ageing-related diseases. Overall, no significant effects on the endocrine, muscular, or neurological systems were found. The effects of rapamycin or its derivatives on the respiratory, digestive, renal, and reproductive systems were not assessed. No serious adverse events attributed to rapamycin and its derivatives were reported in healthy individuals; however, there were increased numbers of infections and increases in total cholesterol, LDL cholesterol, and triglycerides in individuals with ageing-related diseases. Future studies should assess the remaining unexamined systems and test the effects of long-term exposure to rapamycin and its derivatives.

Immunity against Non-Melanoma Skin Cancer and the Effect of Immunosuppressive Medication on Non-Melanoma Skin Cancer Risk in Solid Organ Transplant Recipients

Non-melanoma skin cancers (NMSCs) occur frequently in the Caucasian population and are considered a burden for health care. Risk factors include ultraviolet (UV) radiation, ethnicity and immunosuppression. The incidence of NMSC is significantly higher in solid organ transplant recipients (SOTRs) than in immunocompetent individuals, due to immunosuppressive medication use by SOTRs. While the immunosuppressive agents, calcineurin inhibitors and purine analogues increase the incidence of NMSC in transplant recipients, mTOR inhibitors do not. This is most likely due to the different immunological pathways that are inhibited by each class of drug. This review will focus on what is currently known about the immune response against cutaneous squamous cell carcinoma (cSCC) and basal cell carcinoma (BCC), two of the main types of NMSC. Furthermore, we will describe the different classes of immunosuppressants given to SOTRs, which part of the immune system they target and how they can contribute to NMSC development. The risk of developing NMSC in SOTRs is the result of a combination of inhibiting immunological pathways involved in immunosurveillance against NMSC and the direct (pro/anti) tumor effects of immunosuppressants.

Topical Sirolimus 0.2% Gel for the Management of Tuberous Sclerosis Complex-Related Cutaneous Manifestations: An Interim Analysis of Postmarketing Surveillance in Japan

INTRODUCTION

Tuberous sclerosis complex (TSC) is a rare autosomal dominant genetic disorder affecting several organs, including skin. We sought to assess the real-world effectiveness and safety of a topical sirolimus 0.2% gel treatment for TSC-related cutaneous manifestations.

METHODS

We conducted an interim analysis of postmarketing surveillance conducted in Japan over 52 weeks. A total of 635 and 630 patients were included in the safety and efficacy analysis sets, respectively. Improvement rate of overall cutaneous manifestations, responder rate of improvement in individual lesions, adverse events (AEs), adverse drug reactions (ADRs), and patient satisfaction level of topical sirolimus 0.2% gel treatment were evaluated along with patient characteristics associated with the improvement rate of cutaneous manifestations or safety.

RESULTS

The mean age of the patients was 22.9 years and 46.1% were men. At week 52 of treatment, the overall improvement rate was 74.8% and the responder rate was the highest for facial angiofibroma (86.2%). Overall, the incidence rates of AEs and ADRs were 24.6% and 18.4%, respectively. Efficacy was associated with age (< 15, ≥ 15 to < 65, and ≥ 65 years, p = 0.010), duration of use (p < 0.001), and total dosage (p = 0.005). Safety was associated with age (< 15, ≥ 15 to < 65, and ≥ 65 years, p = 0.011) and duration of use (p < 0.001). However, when the broad age group (≥ 15 to < 65) was subcategorized by 10-year intervals, the incidence of ADRs was similar among the age groups with no significant differences. Hepatic or renal impairment or concomitant use of systemic mTOR inhibitors had no effect on the effectiveness or safety. Overall, 53% of patients were "very satisfied" or "satisfied" with the treatment received.

CONCLUSIONS

Topical sirolimus 0.2% gel is effective in the management of TSC-related cutaneous manifestations and generally well tolerated. Age and duration of usage had a significant association with the effectiveness or safety of topical sirolimus 0.2% gel, whereas total dosage had a significant association with the effectiveness.

Skin cancer in solid organ transplant recipients: still an open problem

In the last two decades, the optimization of organ preservation and surgical techniques, and the personalized immunosuppression have reduced the rate of acute rejections and early post-transplant complications. However, long-term graft survival rates have not improved over time, and evidence suggest a role of chronic calcineurin inhibitor toxicity in this failure. Solid organ transplant recipients may develop chronic dysfunction/damage and several comorbidities, including post-transplant malignancies. Skin cancers, mostly non-melanoma skin cancers (squamous cell carcinoma and basal cell carcinoma), are the most common malignancies in Caucasian solid organ transplant recipients. Several factors, together with immunosuppression, may contribute to the susceptibility for skin cancers which, although often treatable, could be associated with a much higher mortality rate than in the general population. The rapid identification and treatment (including reduction of immunosuppression and early surgical treatments) have an important role to avoid an aggressive behavior of these malignancies. Organ transplant recipients with a history of skin cancer should be followed closely for developing new and metastatic lesions. Additionally, patient education on the daily use of sun-protective measures and the recognition of the early signs (self-diagnosis) of coetaneous malignancies are useful preventive measures. Finally, clinicians should make themselves aware of the problem and build, in every clinical follow-up center, collaborative network involving transplant clinicians, dermatologists and surgeons who should work together to easily identify and rapidly treat these complications. In this review, we discuss the current literature regarding the epidemiology, risk factors, diagnosis, preventive strategies and treatments of skin cancer in organ transplantation.

Management of drug-induced neutropenia, thrombocytopenia, and anaemia after solid organ transplantation: A comprehensive review

WHAT IS KNOWN AND OBJECTIVE

Advances in the development of more effective immunosuppressive drugs have increased graft survival and drug induced adverse effects. Haematological complications including neutropenia, thrombocytopenia, and anaemia are common side effects that affect the grafts' and patients' outcomes. Several studies have stated the important role of various medications in haematological complications after transplantation. They have reported the incidence and different mechanisms of drug induced cytopenia, as well as an overview of possible treatment modalities. However, there is no comprehensive protocol for the management of these complications following transplantation. This narrative review was performed to develop a comprehensive practical approach for management of drug induced haematological complications following solid organ transplantation.

METHOD

PubMed, Embase, Cochrane library, Web of Science, and Google scholar databases were searched without time limitations until March, 2021. In addition, some valid drug information data bases (Uptodate and Micromedex) were searched for detailed information until October, 2021.

RESULTS AND DISCUSSION

Several immunosuppressive and antimicrobial medications may induce neutropenia, thrombocytopenia or anaemia following transplantation. Most of these agents cause dose-related cytopenia, which resolves with dose reduction or drug withdrawal. However, any change in medications may result in negative consequences such as severe infections, bleeding, cardiovascular complications, acute allograft rejection, and graft or patient loss. Thus, cautious evaluation of the patient's condition and the pharmacological properties of the culprit medication are required.

WHAT IS NEW AND CONCLUSION

Three algorithms are presented to guide healthcare providers in the stepwise management of drug-induced neutropenia, thrombocytopenia, and anaemia after solid organ transplantation.

Rapamycin in Cerebral Cavernous Malformations: What Doses to Test in Mice and Humans

Cerebral cavernous malformations (CCMs) are hemorrhagic neurovascular lesions that affect more than 1 million people in the United States. Rapamycin inhibits CCM development and bleeding in murine models. The appropriate dosage to modify disease phenotype remains unknown. Current approved indications by the U.S. Food and Drug Administration and clinicaltrials.gov were queried for rapamycin human dosing for various indications. A systematic literature search was conducted on PubMed to investigate mouse dosimetry of rapamycin. In humans, low daily doses of <2 mg/day or trough level targets <15 ng/mL were typically used for benign indications akin to CCM disease, with relatively low complication rates. Higher oral doses in humans, used for organ rejection, result in higher complication rates. Oral dosing in mice, between 2 and 4 mg/kg/day, achieved blood trough levels in the 5-15 ng/mL range, a concentration likely to be targeted in human studies to treat CCM. Preclinical studies are needed utilizing dosing strategies which achieve blood levels corresponding to likely human dosimetry.

Achromobacter denitrificans pneumonia in a kidney transplant recipient - dose-dependent decrease of phagocytic activity as a potential mechanism for everolimus pulmonary toxicity

Mammalian target of rapamycin (mTOR) inhibitors inclusive regimens are associated with increased risk of pulmonary toxicity, but the underlying mechanism has not been elucidated so far.

We present the case of a 68-year-old man, after deceased-donor kidney transplantation (KTx), maintained on de novo everolimus (EVR) based immunosuppression, who developed Achromobacter denitrificans pneumonia 3 months after KTx. There was clinical improvement with antibiotic treatment, but without a radiological resolution. An additional reduction of the EVR dose resulted only in partial resolution of radiological abnormalities. We performed a functional analysis of peripheral blood neutrophils and monocytes. The ability of phagocytosis and oxidative burst generation against A. denitrificans and Escherichia coli was significantly decreased on EVR treatment as compared to the control healthy person, and significantly improved after 3 weeks of EVR absence. Additionally, these processes were significantly affected by increasing doses of EVR in vitro in the control healthy donor in a dose-dependent manner. EVR discontinuation, with no additional antibiotic treatment, resulted in complete recovery and resolution of pulmonary infiltrates.

Our findings suggest that dose-dependent impairment of neutrophil/monocyte phagocytic activity and oxidative burst generation might be a potential mechanism for EVR pulmonary toxicity.

Oral health in children with chronic kidney disease

The review summarizes the current understanding of dental health in children with chronic kidney disease (CKD). Oral conditions associated with CKD and its medical and surgical management have been described in cohort studies. Children with CKD may present with severe developmental defects of enamel (DDE) including discoloration, pitting, and reduced hardness leading to extensive tooth wear with normal function. The alkaline oral pH resulting from the uremia of CKD inhibits cariogenic bacteria, reduces dental caries risk, and increases accumulation of dental calculus. The malnutrition, acidosis, growth hormone resistance, anemia, and renal osteodystrophy in CKD provide multiple mechanisms for abnormal craniofacial growth and delayed tooth eruption. Following successful kidney transplant, caries risk increases due to normalization of oral pH in the presence of DDE; optimized diet and oral hygiene become critical in caries control. Post-transplant medications including cyclosporine A and calcium channel blockers may cause gingival overgrowth which in severe cases requires gingival surgery to allow tooth eruption, improve appearance, or permit orthodontic treatment. Immune suppression with sirolimus or everolimus may cause severe debilitating oral ulcerations. Long-term immune suppression increases the risk for development of oral candidiasis and oral cancers. Dental examinations and treatment are recommended for children with all stages of CKD to mitigate adverse oral outcomes of the disease and its management.

Overview of therapeutic drug monitoring of immunosuppressive drugs: Analytical and clinical practices

Immunosuppressant drugs (ISDs) play a key role in short-term patient survival together with very low acute allograft rejection rates in transplant recipients. Due to the narrow therapeutic index and large inter-patient pharmacokinetic variability of ISDs, therapeutic drug monitoring (TDM) is needed to dose adjustment for each patient (personalized medicine approach) to avoid treatment failure or side effects of the therapy. To achieve this, TDM needs to be done effectively. However, it would not be possible without the proper clinical practice and analytical tools. The purpose of this review is to provide a guide to establish reliable TDM, followed by a critical overview of the current analytical methods and clinical practices for the TDM of ISDs, and to discuss some of the main practical aspects of the TDM.

Rapamycin promotes autophagy cell death of Kaposi's sarcoma cells through P75NTR activation

The mammalian target of rapamycin inhibitor (mTOR-I) Rapamycin, a drug widely used in kidney transplantation, exerts important anti-cancer effects, particularly in Kaposi's Sarcoma (KS), through several biological interactions. In this in vivo and in vitro study, we explored whether the activation of the autophagic pathway through the low-affinity receptor for nerve growth factor, p75^NTR , may have a pivotal role in the anti-cancer effect exerted by Rapamycin in S. Our Kimmunohistochemistry results revealed a significant hyper-activation of the autophagic pathway in KS lesions. In vitro experiments on KS cell lines showed that Rapamycin exposure reduced cell viability by increasing the autophagic process, in the absence of apoptosis, through the transcriptional activation of p75^NTR via EGR1. Interestingly, p75^NTR gene silencing prevented the increase of the autophagic process and the reduction of cell viability. Moreover, p75^NTR activation promoted the upregulation of phosphatase and tensin homolog (PTEN), a tumour suppressor that modulates the PI3K/Akt/mTOR pathway. In conclusion, our in vitro data demonstrated, for the first time, that in Kaposi's sarcoma, autophagy triggered by Rapamycin through p75^NTR represented a major mechanism by which mTOR inhibitors may induce tumour regression. Additionally, it suggested that p75^NTR protein analysis could be proposed as a new potential biomarker to predict response to Rapamycin in kidney transplant recipients affected by Kaposi's sarcoma.

Treatment of Hypertension Because of Immunosuppressive Therapy After Solid Organ Transplantation-Pharmacological Approach

ABSTRACT

Solid organs transplantation procedures have been performed for more than half a century. Growing knowledge of immune response and development of new immunosuppressive regimens guarantee more and more successful outcomes. However, many of the applied drugs lead to cardiovascular complications, the most frequent of which is hypertension. This article describes epidemiology, pathogenetic mechanisms, and treatment of hypertension induced by immunosuppressive medication. The main impact is focused on drugs belonging to the following groups: calcineurin inhibitors, the inhibitors of the mammalian target of rapamycin, and glucocorticosteroids. We analyze the mechanism of action of the main hypertensive drugs and their influence on the reversing hypertonic action of the immunosuppressive agents. In the absence of current guidelines addressing this problem, this article is an attempt to fill the gap, helping clinicians to choose proper medication.

Modeling Neoplastic Growth in Renal Cell Carcinoma and Polycystic Kidney Disease

Renal cell carcinoma (RCC) and autosomal dominant polycystic kidney disease (ADPKD) share several characteristics, including neoplastic cell growth, kidney cysts, and limited therapeutics. As well, both exhibit impaired vasculature and compensatory VEGF activation of angiogenesis. The PI3K/AKT/mTOR and Ras/Raf/ERK pathways play important roles in regulating cystic and tumor cell proliferation and growth. Both RCC and ADPKD result in hypoxia, where HIF-α signaling is activated in response to oxygen deprivation. Primary cilia and altered cell metabolism may play a role in disease progression. Non-coding RNAs may regulate RCC carcinogenesis and ADPKD through their varied effects. Drosophila exhibits remarkable conservation of the pathways involved in RCC and ADPKD. Here, we review the progress towards understanding disease mechanisms, partially overlapping cellular and molecular dysfunctions in RCC and ADPKD and reflect on the potential for the agile Drosophila genetic model to accelerate discovery science, address unresolved mechanistic aspects of these diseases, and perform rapid pharmacological screens.

An open-label randomized clinical trial to evaluate the efficacy of everolimus versus tacrolimus in triple maintenance immunosuppressive therapy for kidney transplant patients

Tacrolimus (TAC), a calcineurin inhibitor, and everolimus (EVL), an mTOR inhibitor, have been used as immunosuppressive (ISS) drugs in post-kidney transplantation therapy. The objective of this study was to compare the efficacy of EVL vs TAC in the ISS maintenance triple therapy. Ninety-seven kidney transplant patients, who received triple maintenance therapy with TAC, mycophenolate mofetil (MMF), and methyl prednisone (PRED), were evaluated. After four months of post-kidney transplant therapy, 30 patients enrolled in a randomized controlled clinical trial, in which 16 patients received TAC+MMF+PRED (cohort 1), and 14 patients switched to EVL+MMF+PRED (cohort 2). The patients were followed-up for 36 months. Two patients from cohort 1 lost their grafts after one year due to non-adherence. Two patients from cohort 2 had intolerance to mTOR inhibitors and were switched back to TAC from EVL. One case (6.25%) in cohort 1 and three cases (21.43%) in cohort 2 of acute T-cell-mediated rejection was observed. Antibody-mediated acute rejection (ABMAR) was observed in four patients (25.0%) in cohort 1, and antibody-mediated chronic rejection (ABMCR) was observed in two patients (12.50%). One patient from cohort 2 lost the graft after 15 months due to polyomavirus infection. The graft survival rate was 87.50% in cohort 1 and 92.86% in cohort 2. This clinical trial showed that the EVL+MMF+PRED triple maintenance therapy was efficacious compared with TAC during 32 months of follow-up. However, further studies are needed to confirm the efficacy of this regimen for long-term graft survival.

Drug-induced peripheral oedema: An aetiology-based review

Many drugs are responsible, through different mechanisms, for peripheral oedema. Severity is highly variable, ranging from slight oedema of the lower limbs to anasarca pictures as in the capillary leak syndrome. Although most often noninflammatory and bilateral, some drugs are associated with peripheral oedema that is readily erythematous (eg, pemetrexed) or unilateral (eg, sirolimus). Thus, drug-induced peripheral oedema is underrecognized and misdiagnosed, frequently leading to a prescribing cascade. Four main mechanisms are involved, namely precapillary arteriolar vasodilation (vasodilatory oedema), sodium/water retention (renal oedema), lymphatic insufficiency (lymphedema) and increased capillary permeability (permeability oedema). The underlying mechanism has significant impact on treatment efficacy. The purpose of this review is to provide a comprehensive analysis of the main causative drugs by illustrating each pathophysiological mechanism and their management through an example of a drug.

The potential of rapalogs to enhance resilience against SARS-CoV-2 infection and reduce the severity of COVID-19

COVID-19 disproportionately affects older people, with likelihood of severe complications and death mirroring that of other age-associated diseases. Inhibition of the mechanistic target of rapamycin complex 1 (mTORC1) has been shown to delay or reverse many age-related phenotypes, including declining immune function. Rapamycin (sirolimus) and rapamycin derivatives are US Food and Drug Administration-approved inhibitors of mTORC1 with broad clinical utility and well established dosing and safety profiles. Based on preclinical and clinical evidence, a strong case can be made for immediate large-scale clinical trials to assess whether rapamycin and other mTORC1 inhibitors can prevent COVID-19 infection in these populations and also to determine whether these drugs can improve outcomes in patients with severe COVID-19.

Mtor inhibitors associated with higher cardiovascular adverse events-A large population database analysis

There are limited real-world data available regarding adverse events (AEs) of immunosuppressants. We utilized the FDA Adverse Event Reporting System (FAERS) database from 2004 to 2018 to perform a retrospective database analysis. We analyzed AE reports due to the individual agents tacrolimus, sirolimus, or everolimus and compared reporting odds ratios of the mTOR inhibitors to tacrolimus. The mTOR inhibitors arm had 1282 reports with 4176 AEs, while the tacrolimus arm had a total of 7587 reports with 20 940 individual AEs. mTOR inhibitors had significantly higher incidences of cardiovascular (ROR 1.95, 95% CI 1.70, 2.23), dermatologic (ROR 1.34, 95% CI 1.04, 1.73), endocrine (ROR 1.52, 95% CI 1.26, 1.82), gastrointestinal (ROR 1.15, 95% CI 1.01, 1.30), infectious disease (ROR 1.35, 95% 1.20, 1.52), musculoskeletal (ROR 1.39, 95% CI 1.13, 1.70), pulmonary (ROR 3.46, 95% 2.97, 4.03), renal (ROR 1.27, 95% CI 1.10, 1.46), and vascular AEs (ROR 3.10, 95% CI 2.14, 4.49). Across every organ type, mTOR inhibitors had greater cardiovascular AEs compared to tacrolimus, specifically in arteriosclerosis, heart failure, hypotension, tachycardia, chest pain, edema, and pericardial disorders. mTOR inhibitors may be associated with higher cardiovascular AEs. Further investigation is required to determine the potential mechanism of this effect.

Efficacy of Sirolimus in Patients Requiring Tracheostomy for Life-Threatening Lymphatic Malformation of the Head and Neck: A Report From the European Reference Network

Extensive lymphatic malformations (LMs) of the head and neck region may require tracheostomy to secure the airway. Treatment of these life-threatening LMs is usually multimodal and includes sclerotherapy and surgery, among others. Recently, systemic therapy with sirolimus has been introduced as an effective treatment for venous and lymphatic malformations; its efficacy and safety profile in patients with extensive LM requiring tracheostomy are, however, as yet not fully known. We performed a retrospective, multicenter review and identified 13 patients with an extensive LM of the head and neck region, who previously underwent placement of tracheostomy and subsequently received sirolimus treatment with the aim to improve the local respiratory situation and remove the tracheostomy. Under sirolimus therapy, tracheostomy could be reversed in 8/13 (62%) patients, a further 2/13 (15%) patients improved markedly, and removal of the tracheostomy was planned at the time of writing, while 3/13 (23%) patients showed insufficient or absent response to sirolimus, rendering tracheostomy reversal not feasible. The median duration of sirolimus treatment until removal of tracheostomy was 18 months (range, 8 months to 5.6 years). Adverse events of sirolimus therapy were common [10/13 (77%) patients], yet the majority of these were mild [9/10 (90%) patients] and only one severe adverse event was recorded, with ulceration and necrosis at a catheter insertion site. In conclusion, sirolimus can be considered an effective and safe salvage treatment in patients with extensive LM even after placement of a tracheostomy, as closure of the latter was possible in the majority of patients (62%) of our retrospective cohort. A better understanding of when to start sirolimus therapy, of the duration of treatment, and of factors allowing the prediction of treatment response will require further investigation.

Upper Extremity Lymphedema Related to Everolimus in a Renal Transplant Recipient: Efficacy of Complete Decongestive Therapy

We report our experience with a new case of lymphedema of the upper extremity in a renal transplant recipient under treatment with everolimus immunosuppression, and we emphasize the effects of complete decongestive therapy on this chronic condition.

Nutritional Challenges in Pregnant Women with Renal Diseases: Relevance to Fetal Outcomes

Pregnancy in women affected by chronic kidney disease (CKD) has become more common in recent years, probably as a consequence of increased CKD prevalence and improvements in the care provided to these patients. Management of this condition requires careful attention since many clinical aspects have to be taken into consideration, including the reciprocal influence of the renal disease and pregnancy, the need for adjustment of the medical treatments and the high risk of maternal and obstetric complications. Nutrition assessment and management is a crucial step in this process, since nutritional status may affect both maternal and fetal health, with potential effects also on the future development of adult diseases in the offspring. Nevertheless, few data are available on the nutritional management of pregnant women with CKD and the main clinical indications are based on small case series or are extrapolated from the general recommendations for non-pregnant CKD patients. In this review, we discuss the main issues regarding the nutritional management of pregnant women with renal diseases, including CKD patients on conservative treatment, patients on dialysis and kidney transplant patients, focusing on their relevance on fetal outcomes and considering the peculiarities of this population and the approaches that could be implemented into clinical practice.

Effects of Antirejection Drugs on Innate Immune Cells After Kidney Transplantation

Over the last decades, our understanding of adaptive immune responses to solid organ transplantation increased considerably and allowed development of immunosuppressive drugs targeting key alloreactive T cells mechanism. As a result, rates of acute rejection dropped and short-term graft survival improved significantly. However, long-term outcomes are still disappointing. Recently, increasing evidence supports that innate immune responses plays roles in allograft rejection and represents a valuable target to further improve long-term allograft survival. Innate immune cells are activated by molecules with stereotypical motifs produced during injury (i.e., damage-associated molecular patterns, DAMPS) or infection (i.e., pathogen-associated molecular patterns, PAMPs). Activated innate immune cells can exert direct pro- and anti-inflammatory effects, while also priming adaptive immune responses. These cells are activated after transplantation by multiple stimuli, including ischemia-reperfusion injury, rejection, and infections. Data from animal models of graft rejection, show that inhibition of innate immunity promotes development of tolerance. Therefore, understanding mechanisms of innate immunity is important to improve graft outcomes. This review discusses effects of currently used immunosuppressive agents on innate immune responses in kidney transplantation.

Comparative transcriptome analysis of peripheral blood mononuclear cells in renal transplant recipients in everolimus- and tacrolimus-based immunosuppressive therapy

To better define the biological impact of immunosuppression on peripheral blood mononuclear cells (PBMC), we employed RNASeq analysis to compare the whole transcriptomic profile of a group of renal transplant recipients undergoing maintenance treatment with Everolimus (EVE) with those treated with Tacrolimus (TAC). Then, obtained results were validated by classical biomolecular methodologies. The statistical analysis allowed the identification of four genes discriminating the 2 study groups: Sushi Domain Containing 4 (SUSD4, P = 0.02), T Cell Leukemia/Lymphoma 1A (TCL1A, P = 0.02), adhesion G protein-coupled receptor E3 (ADGRE3, P = 0.01), Immunoglobulin Heavy Constant Gamma 3 (IGHG3, P = 0.03). All of them were significantly down-regulated in patients treated with EVE compared to TAC. The Area under Receiver Operating Characteristic (AUROC) of the final model based on these 4 genes was 73.1% demonstrating its good discriminative power. RT-PCR and ELISA validated transcriptomic results. Additionally, an in vitro model confirmed that EVE significantly down-regulates (P<0.001) TCL1A, SUSD4, ADGRE3 and IgHG3 in PBMCs as well as in T cells and monocytes isolated from healthy subjects. Taken together, our data, revealed, for the first time, a new four gene-based transcriptomic fingerprint down-regulated by EVE in PBMCs of renal transplant patients that could improve the available knowledge regarding some of the biological/cellular effects of the mTOR-Is (including their antineoplastic and immune-regulatory properties).

Adverse effects of mycophenolic acid in renal transplant recipients: gender differences

Background Mycophenolic acid is widely used immunosuppressive drug, associated with adverse effects which increase patient morbidity and decrease medication adherence. Objective To evaluate the adverse effects in renal transplant recipients under mycophenolate treatment with respect to gender. Setting University Clinical Centre of Nis, Clinic of Nephrology, Serbia. Method This research included 96 renal transplant recipients, who received immunosuppressive regimen, based on tacrolimus or cyclosporin A, prednisone and mycophenolic acid. The high-performance liquid chromatography method combined with protein precipitation was used for the analysis of mycophelate concentration in human plasma. Drug concentration and dose-adjusted concentration were determined with respect to the patients' gender. An adverse effect scoring system developed by nephrologists within the University of Buffalo Nephrology/Transplant Program was used to monitor adverse effects of therapy. Main outcome measure Individual and scores of adverse effects in relation to the dosing regimen and gender. Results Results showed statistically lower dose and concentrations in men compared to the women in our investigation group. Also, female patients demonstrated higher mean scores (cumulative and subscores) within the same dosing regimens of mycophenolic acid. The gastrointestinal score was significantly higher in women who received a dose greater than 720 mg compared to men (0.20 ± 0.12 vs 0.12 ± 0.12). Women demonstrated higher individual adverse effects such as diarrhea and skin changes (41.7 vs 17.0; p = 0.038 and 62.5 vs 30.2; p = 0.037, respectively). Conclusions The results of our research showed that recipients' gender may play an important role in pharmacokinetic profile of mycophenolic acid, suggesting that women had higher concentration of mycophenolic acid and more serious side effects.

Cancer and mTOR inhibitors in kidney transplantation recipients

Background

Previous studies show that mTOR inhibitors decrease the risk of cancer development after kidney transplantation. However, the effect of cumulative doses of mTOR inhibitors on cancer after kidney transplantation is not well known.

Methods

In the current study, patients were registered into a national database in Taiwan. Between year 2000 and 2013, 4,563 patients received kidney transplantation. They were divided into two groups, according to mTOR inhibitors usage. The cumulative dose of mTOR inhibitors was recorded. Patients were followed-up until de novo cancer development, death, or the end of 2014.

Results

Patients were divided into two groups: mTOR inhibitors users (study group, n = 828) and mTOR inhibitors non-users (control group, n = 3,735). The median follow-up duration was 7.8 years. The risk of de novo cancer (hazards ratio (HR) 0.80, 95% CI [0.60–1.09], p = 0.16) and risk of death (HR 1.14, 95% CI [0.82–1.60], p = 0.43) was not different between mTOR inhibitor user and non-user groups. Neither high- nor low-dose exposure to mTOR inhibitors was associated with increased risk of cancer or mortality. Analysis of cancer subtypes showed no influence by mTOR inhibitors. In addition, the cause of mortality was not significantly different between the two groups.

Discussion

We could not find the association of mTOR inhibitors use and risk of de novo cancer development or mortality in patients with kidney transplantation in Chinese patients. Cumulative exposure to mTOR inhibitors did not change the results.

In Vitro Identification of New Transcriptomic and miRNomic Profiles Associated with Pulmonary Fibrosis Induced by High Doses Everolimus: Looking for New Pathogenetic Markers and Therapeutic Targets

The administration of Everolimus (EVE), a mTOR inhibitor used in transplantation and cancer, is often associated with adverse effects including pulmonary fibrosis. Although the underlying mechanism is not fully clarified, this condition could be in part caused by epithelial to mesenchymal transition (EMT) of airway cells. To improve our knowledge, primary bronchial epithelial cells (BE63/3) were treated with EVE (5 and 100 nM) for 24 h. EMT markers (α-SMA, vimentin, fibronectin) were measured by RT-PCR. Transepithelial resistance was measured by Millicell-ERS ohmmeter. mRNA and microRNA profiling were performed by Illumina and Agilent kit, respectively. Only high dose EVE increased EMT markers and reduced the transepithelial resistance of BE63/3. Bioinformatics showed 125 de-regulated genes that, according to enrichment analysis, were implicated in collagen synthesis/metabolism. Connective tissue growth factor (CTGF) was one of the higher up-regulated mRNA. Five nM EVE was ineffective on the pro-fibrotic machinery. Additionally, 3 miRNAs resulted hyper-expressed after 100 nM EVE and able to regulate 31 of the genes selected by the transcriptomic analysis (including CTGF). RT-PCR and western blot for MMP12 and CTGF validated high-throughput results. Our results revealed a complex biological network implicated in EVE-related pulmonary fibrosis and underlined new potential disease biomarkers and therapeutic targets.

Drug repurposing: Ibrutinib exhibits immunosuppressive potential in organ transplantation

Long-term administration of classic immunosuppressants can induce severe adverse effects. The development of novel immunosuppressants confronts great challenges and opportunities. Ibrutinib, an approved drug for B-cell lineages and chronic graft versus host disease (cGVHD), exhibits immunosuppressive efficacy in autoimmune diseases. Ibrutinib's potential as an immunosuppressant in organ transplantation has not been investigated to date. In a xeno-artery patch model ex vivo, ibrutinib inhibited the proliferation of PBMCs (POD 14-42), mainly CD3⁺CD4⁺ and CD3⁺CD8⁺ T cells ex vivo. The secretion of cytokines (IL-6, IL-2 and IFN-γ) was suppressed in response to ibrutinib. In allo-skin transplantation models, ibrutinib delayed the rejection of grafted skins. Ibrutinib decreased the amount of T/B cells and lymphocyte infiltration. Altogether, ibrutinib exhibited immunosuppressive potential through cytokine regulation and T cell inhibition ex vivo and in vitro. Repositioning of ibrutinib as an immunosuppressant will greatly facilitate novel immunosuppressant development.

Immunosuppressants and new onset gallstone disease in patients having undergone renal transplantation

BACKGROUND

There are very few reports describing the development of gallstone disease after renal transplantation (GSDART) in Asia. The aim of this population-based study was to explore the prevalence, predictive factors, and outcomes of newly developed GSDART. The relationship between immunosuppressant and GSDART was also explored.

PATIENTS AND METHODS

Renal transplantation (RT) recipients were identified from the National Health Insurance Research Database of Taiwan during January 1998-December 2012. In total, 2,630 adult patients, who had neither been diagnosed with gallstone disease (GSD) nor undergone cholecystectomy, were included in this study. These patients underwent follow-up till the diagnosis of GSDART was established. Risk factors and post-RT immunosuppressant treatments were investigated and analyzed using Cox regression analysis. The cumulative mortality in patients with and without GSDART was also evaluated.

RESULTS

The final dataset comprised 143 patients who developed GSDART and 2,487 patients who had not been diagnosed with GSDART during the follow-up period. The prevalence of GSDART was 5.4%. On performing univariate analysis, age (p=0.0276) and certain immunosuppressant administrations were identified as significant risk factors for GSDART. After adjusting for age, multivariable analysis showed that everolimus (adjusted hazard ratio 0.287, p=0.0013) was independently associated with the development of GSDART. The overall mortality rate (6.99%, p=0.0341) was significantly decreased in the GSDART group.

CONCLUSION

Increased age was the most consistent risk factor for GSD, and everolimus-based immunotherapy indicated a decreased incidence of GSDART in RT recipients. The long-term mortality rate was significantly decreased in patients with GSDART.

T cell inhibition by pogostone from Pogostemon cablin (Blanco) Benth: In vitro and in vivo immunosuppressive analysis

Various plant-derived compounds exhibit immunosuppressive activity in pre-clinical investigations, suggesting that they may serve as natural alternatives for the prevention of inflammatory disorders and autoimmune diseases. The aim of the current study was to explore the immunosuppressive potential of pogostone (PO) derived from Pogostemon cablin (Blanco) Benth. Carboxyfluorescein diacetate succinimidyl ester-labeled cell tracking demonstrated that PO (20–80 µM) inhibited Concanavalin A (ConA)-stimulated lymphocyte proliferation, which was mediated by G₀/G₁ phase arrest and accompanied by significant decreases in the expression of CD69 (early-stage activation marker) and CD25 (mid-stage activation marker) in T cells, as indicated by flow cytometry analysis. Furthermore, the proliferation blocking ability of PO (5–80 µM) was not associated with cytotoxicity in normal lymphocytes or apoptosis in ConA-stimulated lymphocytes. The inflammatory cytokine profile determination using a cytometric beads assay revealed that PO inhibited release of anti-inflammatory interleukin (IL)-10 and pro-inflammatory IL-6 from the stimulated lymphocytes. Furthermore, PO (10, 20 or 40 mg/kg) ameliorated the T-cell mediated delayed type hypersensitivity response in Balb/c mice by reducing leukocyte infiltration and tissue edema, providing a further validation of the direct immunosuppressive activity of PO. Together, the present data suggest that PO would suppress T cell response via a direct non-cytotoxic inactivation at the early stage, accompanied by regulation of the inflammatory cytokine profile, which highlights clinical implications for treatment of immune-based disorders.

Sirolimus for the treatment of progressive kaposiform hemangioendothelioma: A multicenter retrospective study

Kaposiform hemangioendothelioma (KHE) is an aggressive disease with high morbidity and mortality. The aim of this study was to retrospectively evaluate the efficacy and safety of sirolimus for the treatment of progressive KHE. A multicenter, retrospective cohort study was conducted in patients with progressive KHE treated with sirolimus. A total of 52 patients were analyzed. Thirty-seven (71%) patients exhibited Kasabach-Merritt phenomenon (KMP) and were significantly younger than the patients without KMP [95% confidence interval (CI), 14.39-41.61; p < 0.001]. Patients without KMP were all treated with sirolimus alone, whereas 21 KMP patients with severe symptoms received short-term combination therapy with prednisolone. Overall, 96% and 98% of patients showed improved relief of notable symptoms and/or improved complications at 6 and 12 months after treatment, respectively. After sirolimus treatment, significant decreases in mean severity scores occurred at 6 months (95% CI, 2.23-2.54, p < 0.001) and 12 months (95% CI, 1.53-1.90, p < 0.001). Compared to KMP patients, patients without KMP showed a response that was similar to but less pronounced during the 12 months of treatment (95% CI, 40.87-53.80; p < 0.001). For subgroup analysis of KMP patients, there were no significant differences in tumor shrinkage between those treated with combination therapy and those receiving sirolimus alone (95% CI, 18.11-25.02; p > 0.05). No patients permanently discontinued treatment due to toxicity-related events, and no drug-related deaths occurred. Sirolimus was effective and safe for the treatment of progressive KHE. Sirolimus may be considered as a first-line therapy or as part of a multidisciplinary approach for the treatment of KHE.

Systemic meta-analysis assessing the short term applicability of early conversion to mammalian target of rapamycin inhibitors in kidney transplant

AIM

To consolidate the present evidence of effectiveness in renal functioning and graft survival following early introduction of mammalian target of rapamycin (mTOR) inhibitors with or without calcineurin inhibitors (CNIs) in renal transplant recipients.

METHODS

We analysed the current literature following PROSPERO approval describing the role of immunosuppressive agent, mTOR inhibitors as an alternative to CNI within six months of renal transplant by searching the PubMed, EMBASE, Cochrane, Crossref, and Scopus using MeSH terms.

RESULTS

Six articles of early withdrawal of CNI and introduction of mTOR-inhibitors within six months of renal transplantation were sought. Glomerular filtration rate (GFR) and serum creatinine were significantly better in mTOR inhibitor group with equivalent survival at 12 mo, even though Biopsy Proven Acute rejection was significantly higher in mTOR-inhibitor group.

CONCLUSION

The evidence reviewed in this meta-analysis suggests that early introduction mTOR-inhibitors substantial CNI minimization. The mTOR inhibitors such as everolimus and sirolimus, due to their complementary mechanism of action and favourable nephrotoxicity profile; better glomerular filtration, lower serum creatinine with equivalent survival. Having said that, due to the higher rejection rate, may influence the use of these regimens to patients with moderate to high immunological risk patients.

Management of everolimus-associated adverse events in patients with tuberous sclerosis complex: a practical guide

Tuberous sclerosis complex (TSC) is a genetic disorder characterised by highly variable comorbid dysfunction and subsequent morbidity. The mTOR inhibitor everolimus is indicated for the treatment of adult TSC patients with renal angiomyolipomas (AMLs) and for subependymal giant astrocytoma (SEGA) in both adults and children, based on data from the EXIST-1 and EXIST-2 trials. However, due to the historical predominance of everolimus in the oncology setting, some physicians who treat TSC patients may be unfamiliar with everolimus-associated adverse events (AEs) and appropriate management strategies. This article aims to serve as a resource for specialists including nephrologists, paediatricians, neurologists and geneticists who require practical guidance on the management of events such as non-infectious pneumonitis, rash, stomatitis, infections, and renal AEs. Additional consideration is given to drug interactions, hepatic impairment, fertility, and sexual maturation. Since patients with TSC receive clinical benefit from continued therapy, it is important that everolimus-related events are dealt with appropriately through strategies such as dose modification, interruption, the provision of supportive care, regular monitoring, and patient education.

Efficacy and Safety of Everolimus for Maintenance Immunosuppression of Kidney Transplantation: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Conversion to everolimus is often used in kidney transplantation to overcome calcineurin inhibitor (CNI) nephrotoxicity but there is conflicting evidence for this approach.

OBJECTIVES

To investigate the benefits and harm from randomized clinical trials (RCTs) involving the conversion from CNI to everolimus after kidney transplantation.

METHODS

Databases were searched up to March 2016. Two reviewers independently assessed trials for eligibility and quality, and extracted data. Results are expressed as risk ratio (RR) or mean difference (MD) with 95% confidence intervals (CI).

RESULTS

Eleven RCTs, with a total of 1,633 patients, met the final inclusion criteria. Patients converted to everolimus had improved renal function at 1 year posttransplant with an estimated glomerular filtration rate (eGFR) of 5.36 mL/min per 1.73 m2 greater than patients remaining on CNI (p = 0.0005) and the longer-term results (> 1 year) of renal function was identical to that of 1 year. There was not a substantial difference in graft loss, mortality, and the occurrence of adverse events (AEs) or serious AEs. However, the risks of acute rejection and trial termination due to AEs with everolimus are respectively 1.82 and 2.63 times greater than patients staying on CNI at 1 year posttransplant (p = 0.02, p = 0.03, respectively). Further, those patients who converted to everolimus had a substantially greater risk of anemia, hyperlipidemia, hypercholesterolemia, hypokalemia, proteinuria, stomatitis, mouth ulceration, and acne.

CONCLUSIONS

Conversion from CNI to everolimus after kidney transplantation is associated with improved renal function in the first 5 years posttransplant but increases the risk of acute rejection at 1 year posttransplant and may not be well endured.

Interstitial Lung Disease After Kidney Transplantation and the Role of Everolimus

BACKGROUND

Kidney transplant recipients are at higher risk of developing pulmonary complications related to immunosuppression, and inhibitor of the mammalian target of rapamycin (mTORi) has been reported as a potential cause.

METHODS

Five hundred kidney-transplanted patients were retrospectively analyzed for pulmonary complications on the basis of clinical and instrumental data (chest radiography, high-resolution computed tomography, broncho-alveolar lavage, oximetry).

RESULTS

We found 26 interstitial lung diseases (ILD) (16%): 12 cases (46.2%) were from infections (42.8% by Pneumocystis jirovecii) and 14 cases of ILD (53.8%) resulted as drug-induced ILD (DI-ILD). According to anti-rejection protocols, DI-ILD occurred in 8 patients (57%) while on triple regimen including steroids, everolimus (EVL), and cyclosporine (CyA) and in 6 patients on double regimen with steroids and mTORi: EVL or sirolimus (43%). In ILD+ patients, everolimus trough-concentration (EVL(TLC)) and cyclosporine (2nd-hour concentration: CyA(C2)) levels were higher than in patients in the same regimen but with ILD- (EVL(TLC) [ng/mL] 9.84 versus 6.85; CyA(C2) [ng/mL] 303.97 versus 298.56). The formula that used the combined blood levels of both drugs (EVL(TLC) + CyA(C2)/100) resulted in a significant difference between groups of patients (12.88 ± 1.61 versus 9.83 ± 1.91). Applying receiver operator characteristic curve (ROC) analysis to detect risk of developing ILD when on combined protocol with EVL and CyA, we obtained an area under the curve of 0.8622 (P = .0081) and 0.9082 (P = .0028), respectively, when using EVL(TLC) or the combination formula with both drugs.

CONCLUSIONS

In renal transplant patients, we obtained a relationship of ILD to specific drug concentration. On the basis of ROC analysis, patients on EVL and CyA combined protocol are at risk of ILD when EVL(TLC) is >9.03 ng/mL or >11.41 when a formula with summation of EVL(TLC) and CyA(C2) is used.

Is Early Conversion to mTOR Inhibitors Represent a Suitable Choice in Renal Transplant Recipients? A Systemic Review of Medium-term Outcomes

BACKGROUND

Immunosuppressive therapies are important parts of renal transplantation.

OBJECTIVE

To assess the present literature on the effectiveness of early introduction of mTOR inhibitors with or without calcineurin inhibitors (CNI) in renal transplant recipients in terms of renal functioning and graft survival.

METHODS

The current literature was reviewed following PROSPERO approval, assessing the role of immunosuppressive agent, mTOR inhibitors as an alternative to CNI within 6 months of renal transplantation by searching PubMed, EMBASE, Cochrane, Crossref, and Scopus.

RESULTS

6 articles of early withdrawal of CNI and introduction of mTOR inhibitors within 6 months of renal transplantation were sought. Glomerular filtration rate (GFR) and serum creatinine were better in mTOR inhibitor group at 12 months. Biopsy-proven acute rejection (BPAR) was significantly higher in mTOR inhibitor group, though survival was comparable.

CONCLUSION

On the basis of present literature, the early introduction of mTOR inhibitors causes substantial CNI minimization. The mTOR inhibitors are more favorable due to their complementary mechanism of action and favorable nephrotoxicity profile, better glomerular filtration, and lower serum creatinine with equivalent survival. However, the higher rejection rate may influence the use of these regimens in patients with moderate to high immunological risk.

Targeting mTOR to reduce Alzheimer-related cognitive decline: from current hits to future therapies

INTRODUCTION

The mTOR pathway is involved in the regulation of a wide repertoire of cellular functions in the brain and its dysregulation is emerging as a leitmotif in a large number of neurological disorders. In AD, altered mTOR signaling contributes to the inhibition of autophagy deposition of Aβ and tau aggregates and to the alteration of several neuronal metabolic pathways. Areas covered: In this review, we report all the current findings on the use of mTOR inhibitors (rapamycin, rapalogues) in the treatment of AD. These results support the role of mTOR inhibitors as potential therapeutic agents able to reduce AD hallmarks and recover cognitive performances. Expert commentary: Despite mTOR inhibitors appearing to be ideal compounds to counteract AD, further studies are needed in order to gain knowledge on the involvement of aberrant mTOR in AD, and to standardize a valuable therapeutic approach that can be translated to humans.

Everolimus-induced epithelial to mesenchymal transition (EMT) in bronchial/pulmonary cells: when the dosage does matter in transplantation

BACKGROUND

Everolimus (EVE) is a mammalian target of rapamycin inhibitor (mTOR-I) widely used in transplantation that may determine some severe adverse events, including pulmonary fibrosis. The pathogenic mechanism of mTOR-I-associated pulmonary toxicity is still unclear, but epithelial to mesenchymal transition (EMT) of bronchial/pulmonary cells may play a role.

METHODS

Three cell lines-human type II pneumocyte-derived A549, normal bronchial epithelial, and bronchial epithelial homozygous for the delta F508 cystic fibrosis-causing mutation-were treated with EVE or tacrolimus at different concentrations. Real-time polymerase chain reaction and immunofluorescence were used to evaluate mRNA and protein levels of EMT markers (alpha-SMA, vimentin, fibronectin). Subsequently, in 13 EVE- and 13 tacrolimus-treated patients we compared the rate of lung fibrosis, estimated by an arbitrary pulmonary fibrosis index score (PFIS).

RESULTS

Biomolecular experiments demonstrated that high doses of EVE (100 nM) up-regulated EMT markers in all cell lines at both gene- and protein level. High concentrations of EVE were also able to reduce the mRNA levels of epithelial markers (E-cadherin and ZO-1) and to induce the phosphorylation of AKT. In the in vivo part of the study, PFIS was significantly higher in the EVE-group than the tacrolimus-group (p = 0.03) and correlated with trough levels (R² = 0.35).

CONCLUSIONS

Our data reveal, for the first time, a dose-dependent EVE-induced EMT in airway cells. They suggest that clinicians should employ, wherever possible, low dosages of mTOR-Is in transplant recipients, assessing periodically their pulmonary function.

Possible alternative therapies for oral lichen planus cases refractory to steroid therapies

Oral lichen planus (OLP) is a chronic inflammatory disorder with a multifactorial etiopathogenesis. Immune dysregulation plays a critical role in the development and progression of this disease. Patients' lives may be affected by pain caused by atrophic-erosive lesions. Given the obscure etiology, treatment is usually symptomatic. Topical steroids remain the mainstay of management. However, their therapeutic benefits are not always evident. There are substantial data on the possible therapeutic strategies that are effective in OLP cases refractory to steroids. This review provides an overview of the current approaches for the management of steroid-refractory OLP. The miscellaneous treatment regimens include tacrolimus, pimecrolimus, thalidomide, low-level laser therapy, photodynamic therapy, and surgical excision. Some results obtained from these studies were promising. However, further studies, especially randomized controlled trials with strict inclusion and exclusion criteria and larger sample sizes, are required for the evaluation of the long-term safety and efficacy of these therapies.

Safety of mTOR inhibitors in adult solid organ transplantation

INTRODUCTION

Mammalian target of rapamycin (mTOR) inhibitors (sirolimus and everolimus) are a class of immunosuppressive drugs approved for solid organ transplantation (SOT). By inhibiting the ubiquitous mTOR pathway, they present a peculiar safety profile. The increased incidence of serious adverse events in early studies halted the enthusiasm as a kidney sparing alternative to calcineurin inhibitors (CNI).

AREAS COVERED

Herein we review mTOR inhibitors safety profile for adult organ transplantation, ranging from acute side effects, such as lymphoceles, delayed wound healing, or cytopenias, to long-term ones which increase morbidity and mortality, such as cancer risk and metabolic profile. Infection, proteinuria, and cutaneous safety profiles are also addressed.

EXPERT OPINION

In the authors' opinion, mTOR inhibitors are a safe alternative to standard immunosuppression therapy with CNI and mycophenolate/azathioprine. Mild adverse events can be easily managed with an increased awareness and close monitoring of trough levels. Most serious side effects are dose- and organ-dependent. In kidney and heart transplantation mTOR inhibitors may be safely used as either low-dose de novo or through early-conversion. In the liver, conversion 4 weeks post-transplantation may reduce long-term chronic kidney disease secondary to calcineurin nephrotoxicity, without increasing hepatic artery/portal vein thrombosis.

Epithelial to mesenchymal transition in the liver field: the double face of Everolimus in vitro

Background

Everolimus (EVE), a mammalian target of rapamycin inhibitor, has been proposed as liver transplant immunosuppressive drug, gaining wide interest also for the treatment of cancer. Although an appropriate tolerance, it may induce several adverse effects, such as fibro-interstitial pneumonitis due to the acquisition of activated myofibroblasts. The exact molecular mechanism associated with epithelial to mesenchymal transition (EMT) may be crucial also in the liver context. This work examines the role and the molecular mediators of EMT in hepatic stellate cell (HSC) and human liver cancer cells (HepG2) and the potential role of EVE to maintain the epithelial phenotype rather than to act as a potential initiators of EMT.

Methods

Real time-PCR and western blot have been used to assess the capability of EVE at low-therapeutic (10 nM) and high (100 nM) dose to induce an in vitro EMT in HSC and HepG2.

Results

Biomolecular experiments demonstrated that low concentration of EVE (10 nM) did not modify the gene expression of alpha-smooth muscle actin (α-SMA), Vimentin (VIM), Fibronectin (FN) in both HSC and HepG2 cells, whereas EVE at 100 nM induced a significant over-expression of all the three above-mentioned genes and an increment of α-SMA and FN protein levels. Additionally, 100 nM of EVE induced a significant phosphorylation of AKT and an up-regulation of TGF-β expression in HSC and HepG2 cells.

Discussion

Our data, although obtained in an in vitro model, revealed, for the first time, that high concentration of EVE may induce EMT in liver cells confirming previous published evidences obtained in renal cells. Additionally, they suggested that mTOR-I should be administered at the lowest dose able to maximize their important and specific therapeutic properties minimizing or avoiding fibrosis-related adverse effects.

Conclusions

In summary, if confirmed by additional studies, our results could be useful for researchers to standardize new therapeutic immunosuppressive and anticancer drugs protocols.

Blocking rpS6 Phosphorylation Exacerbates Tsc1 Deletion-Induced Kidney Growth

The molecular mechanisms underlying renal growth and renal growth-induced nephron damage remain poorly understood. Here, we report that in murine models, deletion of the tuberous sclerosis complex protein 1 (Tsc1) in renal proximal tubules induced strikingly enlarged kidneys, with minimal cystogenesis and occasional microscopic tumorigenesis. Signaling studies revealed hyperphosphorylation of eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1) and increased phosphorylation of ribosomal protein S6 (rpS6) in activated renal tubules. Notably, knockin of a nonphosphorylatable rpS6 in these Tsc1-mutant mice exacerbated cystogenesis and caused drastic nephron damage and renal fibrosis, leading to kidney failure and a premature death rate of 67% by 9 weeks of age. In contrast, Tsc1 single-mutant mice were all alive and had far fewer renal cysts at this age. Mechanistic studies revealed persistent activation of mammalian target of rapamycin complex 1 (mTORC1) signaling causing hyperphosphorylation and consequent accumulation of 4E-BP1, along with greater cell proliferation, in the renal tubules of Tsc1 and rpS6 double-mutant mice. Furthermore, pharmacologic treatment of Tsc1 single-mutant mice with rapamycin reduced hyperphosphorylation and accumulation of 4E-BP1 but also inhibited phosphorylation of rpS6. Rapamycin also exacerbated cystic and fibrotic lesions and impaired kidney function in these mice, consequently leading to a premature death rate of 40% within 2 weeks of treatment, despite destroying tumors and decreasing kidney size. These findings indicate that Tsc1 prevents aberrant renal growth and tumorigenesis by inhibiting mTORC1 signaling, whereas phosphorylated rpS6 suppresses cystogenesis and fibrosis in Tsc1-deleted kidneys.