Rapamicina oral: una alternativa en niños con anomalías vasculares complicadas / Oral rapamycin: an alternative in children with complicated vascular abnormalities

Objetivos: El uso del inhibidor mTOR sirolimus ha supuesto unavance en el tratamiento de pacientes con anomalías vasculares complicadas. El objetivo de este estudio es presentar nuestra serie de pacientespediátricos con anomalías vasculares tratados con sirolimus oral y haceruna revisión de la literatura al respecto. Material y métodos: Se realizó un análisis retrospectivo de lospacientes con anomalías vasculares complicadas tratados con sirolimusoral en nuestro centro desde el año 2016. La dosis inicial utilizada fuede 0,8 mg/m2 cada 12 horas y el rango terapéutico de 5-15 ng/ml. Todos los pacientes recibieron profilaxis con trimetoprim-sulfametoxazol. Resultados: Se incluyeron seis niños, tres varones y tres mujeres, con una edad media al inicio del tratamiento de 9,5 años. Trespresentaban una malformación linfática en cabeza y cuello, dos unamalformación venosa en miembro inferior y la última una malformación combinada linfática-venosa a nivel toracoabdominal. Todos habíanrecibido múltiples tratamientos previos sin mejoría. Tras el inicio desirolimus, cinco pacientes mejoraron clínicamente (tiempo medio 3,6meses) y cuatro radiológicamente (tiempo medio 6,6 meses). Se registraron efectos adversos leves y transitorios en tres casos. Actualmente,cinco pacientes continúan con el tratamiento. Conclusiones: El sirolimus oral es un tratamiento eficaz y seguroen pacientes con anomalías vasculares complicadas. Nuestros resultadosapoyan su uso en malformaciones linfáticas y venosas en las que hanfracasado otros tratamientos, presentando buenas respuestas sintomáticasy, en menor medida, radiológicas.(AU)

Objective: Sirolimus mTOR inhibitor represents a major advancein the treatment of patients with complicated vascular abnormalities.The objective of this study was to present our series of pediatric patientswith vascular abnormalities treated with oral sirolimus, and to conducta review of the relevant literature. Materials and methods: A retrospective analysis of patients withcomplicated vascular abnormalities treated with oral sirolimus in ourhealthcare facility from 2016 was carried out. Initial dosage was 0.8 mg/m 2 every 12 hours, and therapeutic range was 5-15 ng/ml. All patientsreceived trimethoprim-sulfamethoxazole prophylaxis. Results: 6 children –3 boys and 3 girls– with a mean age of 9.5years at treatment initiation were included. 3 of them had head and necklymphatic malformation, 2 had lower limb venous malformation, and 1had combined lymphatic-venous malformation at the thoracoabdominal level. They all had received multiple previous treatments withoutimprovement. Following sirolimus initiation, 5 patients had clinicalimprovement (mean time: 3.6 months) and 4 had radiological improvement (mean time: 6.6 months). Mild and transitory adverse effects werenoted in the 3 cases. Today, 5 patients remain under treatment. Conclusions: Oral sirolimus is an effective and safe treatment inpatients with complicated vascular abnormalities. Our results supportsirolimus use in lymphatic and venous malformations in which previoustreatments have failed, with a good symptomatic and, to a lesser extent,radiological response.(AU)

Rapamycin Inhibitors for Eye Squamous Cell Carcinoma after Renal Transplantation: A Case Report.

INTRODUCTION: The immunosuppressive efficiency obtained in the last decades in kidney transplantation significantly improved graft survival. However, there is still a high risk and incidence of cancer in transplant patients strongly and directly related to the type of immunosuppression. An increasing body of evidence suggests that the PI3K/Akt/mTOR pathway may play a pivotal role in the development and progression of several neoplastic diseases. CASE PRESENTATION: We describe a 47-year-old male patient who received a cadaveric primary renal transplant in November 2008 developing a poorly differentiated infiltrating and ulcerated squamous cell carcinoma (SCC) at the eye level. In this patient, the modification of an immunosuppressive regimen with introduction of rapamycin (mTOR) inhibitors and withdrawal of calcineurin inhibitors (CNIs) led to the resolution of this severe condition. CONCLUSION: The introduction of mTOR inhibitors and withdrawal of CNIs in kidney-transplanted patients with de novo eye SCC should be considered in this clinical setting.

Target of rapamycin inhibitors (TOR-I; sirolimus and everolimus) for primary immunosuppression in kidney transplant recipients.

BACKGROUND: Kidney transplantation is the therapy of choice for many patients with end-stage kidney disease (ESKD) with an improvement in survival rates and satisfactory short term graft survival. However, there has been little improvement in long-term survival. The place of target of rapamycin inhibitors (TOR-I) (sirolimus, everolimus), which have different modes of action from other commonly used immunosuppressive agents, in kidney transplantation remains uncertain. This is an update of a review first published in 2006. OBJECTIVES: To evaluate the short and long-term benefits and harms of TOR-I (sirolimus and everolimus) when used in primary immunosuppressive regimens for kidney transplant recipients. SEARCH METHODS: We searched the Cochrane Kidney and Transplant Register of Studies up to 20 September 2019 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register were identified through searches of CENTRAL, MEDLINE and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov. SELECTION CRITERIA: All randomised controlled trials (RCTs) and quasi-RCTs in which drug regimens, containing TOR-I commenced within seven days of transplant, were compared to alternative drug regimens, were included without age restriction, dosage or language of report. DATA COLLECTION AND ANALYSIS: Three authors independently assessed study eligibility, risk of bias, and extracted data. Results were reported as risk ratios (RR) with 95% confidence intervals (CI) for dichotomous outcomes and mean difference (MD) with 95% CI for continuous outcomes. Statistical analyses were performed using the random-effects model. The certainty of the evidence was assessed using GRADE MAIN RESULTS: Seventy studies (17,462 randomised participants) were included; eight studies included two comparisons to provide 78 comparisons. Outcomes were reported at six months to three years post transplant. Risk of bias was judged to be low for sequence generation in 25 studies, for allocation concealment in 23 studies, performance bias in four studies, detection bias in 65 studies, attrition bias in 45 studies, selective reporting bias in 48 studies, and for other potential bias in three studies. Risk of bias was judged to be at high risk of bias for sequence generation in two studies, allocation concealment in two studies, performance bias in 61 studies, detection bias in one study, attrition bias in four studies, for selective reporting bias in 11 studies and for other potential risk of bias in 46 studies. Compared with CNI and antimetabolite, TOR-I with antimetabolite probably makes little or no difference to death (RR 1.31, 95% CI 0.87 to 1.98; 19 studies) or malignancies (RR 0.86, 95% CI 0.50 to 1.48; 10 studies); probably increases graft loss censored for death (RR 1.32, 95% CI 0.96 to 1.81; 15 studies), biopsy-proven acute rejection (RR 1.60, 95% CI 1.25 to 2.04; 15 studies), need to change treatment (RR 2.42, 95% CI 1.88 to 3.11; 14 studies) and wound complications (RR 2.56, 95% CI 1.94 to 3.36; 12 studies) (moderate certainty evidence); but reduces CMV infection (RR 0.43, 95% CI 0.29 to 0.63; 13 studies) (high certainty evidence). Compared with antimetabolites and CNI, TOR-I with CNI probably makes little or no difference to death (RR 1.06, 95% CI 0.84 to 1.33; 31 studies), graft loss censored for death (RR 1.09, 95% CI 0.82 to 1.45; 26 studies), biopsy-proven acute rejection (RR 0.95, 95% CI 0.81 to 1.12; 24 studies); and malignancies (RR 0.83, 95% CI 0.64 to 1.07; 17 studies); probably increases the need to change treatment (RR 1.56, 95% CI 1.28 to 1.90; 25 studies), and wound complications (RR 1.56, 95% CI 1.28 to 1.91; 17 studies); but probably reduces CMV infection (RR 0.44, 95% CI 0.34 to 0.58; 25 studies) (moderate certainty evidence). Lower dose TOR-I and standard dose CNI compared with higher dose TOR-I and reduced dose CNI probably makes little or no difference to death (RR 1.07, 95% CI 0.64 to 1.78; 9 studies), graft loss censored for death (RR 1.09, 95% CI 0.54 to 2.20; 8 studies), biopsy-proven acute rejection (RR 0.87, 95% CI 0.67 to 1.13; 8 studies), and CMV infection (RR 1.42, 95% CI 0.78 to 2.60; 5 studies) (moderate certainty evidence); and may make little or no difference to wound complications (RR 0.95, 95% CI 0.53 to 1.71; 3 studies), malignancies (RR 1.04, 95% CI 0.36 to 3.04; 7 studies), and the need to change treatments (RR 1.18, 95% CI 0.58 to 2.42; 5 studies) (low certainty evidence). Lower dose of TOR-I compared with higher doses probably makes little or no difference to death (RR 0.84, 95% CI 0.67 to 1.06; 13 studies), graft loss censored for death (RR 0.92, 95% CI 0.71 to 1.19; 12 studies), biopsy-proven acute rejection (RR 1.26, 95% CI 1.10 to 1.43; 11 studies), CMV infection (RR 0.87, 95% CI 0.63 to 1.21; 9 studies), wound complications (RR 0.92, 95% CI 0.66 to 1.29; 7 studies), and malignancy (RR 0.84, 95% CI 0.54 to 1.32; 10 studies) (moderate certainty evidence); and may make little or no difference to the need to change treatments (RR 0.91, 95% CI 0.78 to 1.05; 10 studies) (low certainty evidence). It is uncertain whether sirolimus and everolimus differ in their effects on kidney function and lipid levels because the certainty of the evidence is very low based on a single small study with only three months of follow-up. AUTHORS' CONCLUSIONS: In studies with follow-up to three years, TOR-I with an antimetabolite increases the risk of graft loss and acute rejection compared with CNI and an antimetabolite. TOR-I with CNI potentially offers an alternative to an antimetabolite with CNI as rates of graft loss and acute rejection are similar between interventions and TOR-I regimens are associated with a reduced risk of CMV infections. Wound complications and the need to change immunosuppressive medications are higher with TOR-I regimens. While further new studies are not required, longer-term follow-up data from participants in existing methodologically robust RCTs are needed to determine how useful immunosuppressive regimens, which include TOR-I, are in maintaining kidney transplant function and survival beyond three years.

Long non­coding RNA SENCR alleviates the inhibitory effects of rapamycin on human umbilical vein endothelial cells.

Rapamycin (RPM) is frequently used as the drug coating in drug­eluting stents (DESs) as it can inhibit the growth of smooth muscle cells. However, RPM also inhibits the proliferation and migration of vascular endothelial cells, and impairs reendothelialization in DES implantation. Therefore, the development of a strategy to protect vascular endothelial cells after DES implantation is of great importance. Long non­coding RNAs (lncRNAs) metastasis­associated lung adenocarcinoma transcript 1 (MALAT1) and smooth muscle and endothelial cell­enriched migration/differentiation­associated lncRNA (SENCR) are able to enhance the proliferation, migration and angiogenesis of endothelial cells, which suggests that they may have potential as antagonists of the adverse effects of RPM in DES. However, the relationship between RPM and lncRNAs in endothelial cells during the intervention is not fully understood at present. The current study investigated the role and potential mechanism of the lncRNA SENCR on the activity of human umbilical vein endothelial cells (HUVECs) after RPM treatment. The proliferation, migration, angiogenic capacity and cell cycle progression of lncRNA SENCR­overexpressing HUVECs following RPM treatment was examined. The proliferation­related proteins of lncRNA SENCR­modified HUVECs were evaluated to understand the mechanism of action. LncRNA SENCR significantly alleviated the inhibition of proliferation, migration, angiogenesis and cell cycle progression of HUVECs caused by RPM by activating extracellular signal­regulated kinase 1/2 and mammalian target of RPM. The lncRNA SENCR could alleviate the inhibitory effects of RPM on HUVECs and may be useful as a new combinative agent to avoid the disadvantages of RPM in DES implantation.

Effects of the Mammalian Target of Rapamycin Inhibitor Everolimus on Hepatitis C Virus Replication In Vitro and In Vivo.

BACKGROUND: The influence of immunosuppressants on hepatitis C virus (HCV) re-infection after liver transplantation, particularly mammalian target of rapamycin inhibitors, remains unclear. The aim of our study was to analyze the influence of everolimus (EVR) on HCV replication activity in the context of underlying molecular mechanisms, with focus on the pro-myelocytic leukemia protein (PML). METHODS: HCV viral load was recorded in 40 patients with post-transplant HCV re-infection before and 8 weeks after introduction of EVR. An HCV cell culture replicon system for genotype (GT) 1b, GT2b, and GT3a was used to compare the influence of EVR on HCV replication for the respective genotypes in vitro. Fluorescence-activated cell-sorting analysis was used to test for effects on cell proliferation. PML expression was silenced with the use of small hairpin RNA constructs, and PML expression was quantified by means of quantitative real-time polymerase chain reaction. RESULTS: In patients with HCV, the viral load of GT1a and GT1b was hardly affected by EVR, whereas the viral load was reduced in patients with GT2a (P ≤ .0001) or GT3 infection (P ≤ .05). In vitro EVR impairs HCV replication activity of GT2a and GT3a up to 60% (P ≤ .0005), whereas in GT1b cells, HCV replication activity is increased by 50% (P ≤ .005). Replicon cell viability was not impaired. HCV replication activity is impaired in the absence of PML, which can be reversed by overexpression of PML isoforms. Furthermore, in the absence of PML, the effect of EVR on HCV replication activity is nearly abrogated. CONCLUSIONS: The mammalian target of rapamycin inhibitor EVR influences HCV replication via PML. The herein presented results suggest a genotype-dependent benefit for an EVR-based immunosuppressive regimen in patients with GT2a or GT3 re-infection after liver transplantation.

Rapamycin modulation of p70 S6 kinase signaling inhibits Rift Valley fever virus pathogenesis.

Despite over 60 years of research on antiviral drugs, very few are FDA approved to treat acute viral infections. Rift Valley fever virus (RVFV), an arthropod borne virus that causes hemorrhagic fever in severe cases, currently lacks effective treatments. Existing as obligate intracellular parasites, viruses have evolved to manipulate host cell signaling pathways to meet their replication needs. Specifically, translation modulation is often necessary for viruses to establish infection in their host. Here we demonstrated phosphorylation of p70 S6 kinase, S6 ribosomal protein, and eIF4G following RVFV infection in vitro through western blot analysis and in a mouse model of infection through reverse phase protein microarrays (RPPA). Inhibition of p70 S6 kinase through rapamycin treatment reduced viral titers in vitro and increased survival and mitigated clinical disease in RVFV challenged mice. Additionally, the phosphorylation of p70 S6 kinase was decreased following rapamycin treatment in vivo. Collectively these data demonstrate modulating p70 S6 kinase can be an effective antiviral strategy.

Costimulatory Blockade and Use of Mammalian Target of Rapamycin Inhibitors: Avoiding Injury Part 1.

Although calcineurin inhibitor drugs have been the mostly used therapy in modern immunosuppression in kidney transplantation, their effect on kidney allograft dysfunction has been suboptimal as far as preservation of kidney function is concerned. Additionally, there are metabolic and other nonmetabolic effects including increased risk of malignancy that has necessitated the use of mammalian target of rapamycin inhibitors to reduce exposure to calcineurin inhibitors. Mammalian target of rapamycin inhibitors, both sirolimus and everolimus, have been studied in several trials to facilitate preservation of kidney function with variable effects on kidney allograft function and immunogenicity. Preservation of kidney function is increasingly becoming the mainstay of immunosuppression not only in kidney transplantation, but also in extrakidney transplantation. The best kidney outcomes have been reported in calcineurin inhibitor withdrawal studies using mammalian target of rapamycin inhibitors, in kidney transplant recipients with stable kidney function. This review article summarizes data from several studies in which mammalian target of rapamycin inhibitors have been used to reduce exposure to or withdraw calcineurin inhibitors in an attempt to preserve kidney function.

Kaempferol targets Krt-14 and induces cytoskeletal mineralization in osteoblasts: A mechanistic approach.

Kaempferol (KEM) has been observed to stimulate Krt-14 protein which subsequently contributes to matrix maturation and mineralization in rat primary osteoblast cells. Incorporation of Krt-14 siRNA results in reduced mRNA and protein expression after 48h post transfection and remained low for 9days. At day 9 Krt-14 siRNA significantly reduced mineralization without concomitant change in the cell number. ColI and OCN gene expression was reduced in Krt-14 siRNA-treated osteoblast cells. Soluble osteocalcin and collagen levels were markedly decreased in conditioned medium as well as in acid-salt soluble cell-ECM layer treated with Krt-14 siRNA compared to control siRNA treated cells corroborated at the ultrastructral level by AFM. Further, knockdown of Krt-14 and inhibitors against AMPK and mTOR, repressed the activation of mTOR and mineralization attenuated by KEM confirmed the role of Krt-14 in mineralization. These findings strongly suggest that Krt-14 regulates osteoblast mineralization by organizing osteoblast derived ECM.

Telomerase expression abrogates rapamycin-induced irreversible growth arrest of uterine fibroid smooth muscle cells.

Uterine fibroids are the most common solid tumors found in women of reproductive age. It has been reported that deregulation of the mammalian target of rapamycin (mTOR) pathway plays an important role in the etiology of leiomyoma. Here, we investigated the effect of rapamycin, an inhibitor of mTORC1, on the growth of primary fibroid smooth muscle cells (fSMCs) and human telomerase reverse transcriptase (hTERT)-transduced and immortalized fSMCs. With the primary fSMCs, a 24-hour treatment with rapamycin was sufficient to trigger a growth arrest that was not reversible upon drug removal. By contrast, the growth inhibitory effect of rapamycin on the hTERT-transduced fSMCs was readily reversible, as these cells resumed proliferation upon the withdrawal of the drug. These results suggest that rapamycin-induced irreversible growth arrest of fSMCs is dependent on the senescence barrier that is abrogated by the ectopic expression of telomerase.

Side-effects associated with targeted therapies in renal cell carcinoma.

PURPOSE OF REVIEW: With the introduction of multiple new targeted agents for the treatment of metastatic renal cell carcinoma, specific attention must be given to toxicities induced by these agents. RECENT FINDINGS: Agents with activity on the same target can have different toxicities, which might lead the clinician to select or individualize therapies. However, some data also support the concept of maximal tolerated dose as a marker of efficacy. Specific elements of these data are summarized and discussed in the paper. SUMMARY: Toxicity management is pivotal in individualized cancer care. This papers outlines some of the principles related to disease and toxicity management.

Severe everolimus-induced steatohepatis: a case report.

The mammalian target of rapamycin inhibitors are normally favored as immunosuppressant agents for solid organ transplantation such as kidney, liver or heart. Only in recent years have they been increasingly administered for the treatment of neuroendocrine tumors. Even though mammalian target of rapamycin inhibitors are known to exhibit specific side effects, everolimus-related severe hepatic steatosis has not as yet been described in the literature. We report the case of a 76-year-old man who developed severe hepatic steatosis within four weeks of treatment with everolimus as concomitant tumor therapy for a progressively growing neuroendocrine carcinoma of the ileum. A diagnosis of hepatic steatosis was established using computer tomography and fibroscan©. Other underlying causes for steatosis hepatis could be excluded. Further studies are warranted to explain the underlying mechanisms.

Metformin impairs vascular endothelial recovery after stent placement in the setting of locally eluted mammalian target of rapamycin inhibitors via S6 kinase-dependent inhibition of cell proliferation.

OBJECTIVES: This study sought to examine the effect of oral metformin (Mf) therapy on endothelialization in the setting of drug-eluting stents (DES). BACKGROUND: Mf is a commonly used therapy in diabetic patients receiving DES. Mf and locally eluted mammalian target of rapamycin (mTOR) inhibitors used in DES have convergent molecular signaling; however, the impact of this drug interaction on stent endothelialization is unknown. METHODS: We examined human endothelial aortic cells (HAECs) and a rabbit model of stenting to determine points on molecular convergence between these 2 agents and their impact on stent endothelialization. RESULTS: Western blotting of HAECs treated with Mf and the mTOR inhibitor sirolimus and 14-day rabbit iliacs treated with the combination of zotarolimus-eluting stents (ZES) and oral Mf demonstrated greater inhibition of S6 kinase (S6K), a downstream effector of mTOR complex 1, than either treatment alone. HAEC proliferation was significantly inhibited by Mf or sirolimus treatments alone and further reduced when they were combined. Knockdown of S6K via short interfering RNA in HAECs impaired cell proliferation via a cyclin D1-dependent mechanism, whereas its overexpression rescued the antiproliferative effects of both agents. Last, endothelialization and endothelial cell proliferation at 14 days were assessed in rabbits receiving ZES or bare-metal stents and Mf or placebo by scanning electron microscopy and bromodeoxyuridine/CD31 labeling, respectively. Both endpoints were inhibited by ZES treatment alone and were further reduced by the combination of Mf and ZES. CONCLUSIONS: Significant convergence of signaling occurs between Mf and locally delivered mTOR inhibitors at S6K. This further impairs endothelial recovery/proliferation via an S6K-dependent mechanism. Patients receiving Mf in combination with stents that elute mTOR inhibitors are potentially at increased risk of delayed endothelial healing and stent thrombosis.

Differential effects of rapamycin and dexamethasone in mouse models of established allergic asthma.

The mammalian target of rapamycin (mTOR) plays an important role in cell growth/differentiation, integrating environmental cues, and regulating immune responses. Our lab previously demonstrated that inhibition of mTOR with rapamycin prevented house dust mite (HDM)-induced allergic asthma in mice. Here, we utilized two treatment protocols to investigate whether rapamycin, compared to the steroid, dexamethasone, could inhibit allergic responses during the later stages of the disease process, namely allergen re-exposure and/or during progression of chronic allergic disease. In protocol 1, BALB/c mice were sensitized to HDM (three i.p. injections) and administered two intranasal HDM exposures. After 6 weeks of rest/recovery, mice were re-exposed to HDM while being treated with rapamycin or dexamethasone. In protocol 2, mice were exposed to HDM for 3 or 6 weeks and treated with rapamycin or dexamethasone during weeks 4-6. Characteristic features of allergic asthma, including IgE, goblet cells, airway hyperreactivity (AHR), inflammatory cells, cytokines/chemokines, and T cell responses were assessed. In protocol 1, both rapamycin and dexamethasone suppressed goblet cells and total CD4(+) T cells including activated, effector, and regulatory T cells in the lung tissue, with no effect on AHR or total inflammatory cell numbers in the bronchoalveolar lavage fluid. Rapamycin also suppressed IgE, although IL-4 and eotaxin 1 levels were augmented. In protocol 2, both drugs suppressed total CD4(+) T cells, including activated, effector, and regulatory T cells and IgE levels. IL-4, eotaxin, and inflammatory cell numbers were increased after rapamycin and no effect on AHR was observed. Dexamethasone suppressed inflammatory cell numbers, especially eosinophils, but had limited effects on AHR. We conclude that while mTOR signaling is critical during the early phases of allergic asthma, its role is much more limited once disease is established.

Phase I/IIa trial of the mammalian target of rapamycin inhibitor ridaforolimus (AP23573; MK-8669) administered orally in patients with refractory or advanced malignancies and sarcoma.

BACKGROUND: Ridaforolimus is an inhibitor of mTOR with evidence of antitumor activity in an I.V. formulation. This multicenter, open-label, 3 + 3 design nonrandomized, dose-escalation, phase I/IIa trial was conducted to determine the safety, pharmacokinetic (PK) and pharmacodynamic parameters, maximum tolerated dose, and antitumor activity of oral ridaforolimus. PATIENTS AND METHODS: Patients with metastatic or unresectable solid tumors refractory to therapy were eligible. Seven different continuous and intermittent dosing regimens were examined. RESULTS: One hundred and forty-seven patients were enrolled in this study among which 85 were patients with sarcoma. Stomatitis was the most common DLT observed. The dosing regimen, 40 mg QD × 5 days/week, provided the best combination of cumulative dose, dose density, and cumulative exposure, and was the recommended dosing regimen for subsequent clinical development. PK was nonlinear, with less than proportional increases in day-1 blood AUC0-∞ and Cmax, particularly with doses >40 mg. The terminal half-life estimate of ridaforolimus (QD × 5 40 mg) was 42.0 h, and the mean half-life ∼30-60 h. The clinical benefit rate, (complete response, partial response, or stable disease for ≥4 months was 24.5% for all patients and 27.1% for patients with sarcoma. CONCLUSION: Oral ridaforolimus had an acceptable safety profile and exhibited antitumor activity in patients with sarcoma and other malignancies. ClinicalTrials.gov Identifier NCT00112372.

Emerging treatments in the management of tuberous sclerosis complex.

Tuberous sclerosis complex is a genetic disorder characterized by the formation of nonmalignant hamartomas in the brain, heart, skin, kidney, lung, and other organs. It is associated with autism, epilepsy, and other neurocognitive and behavioral disabilities. Wide phenotypic variation occurs in disease severity and natural course: some patients demonstrate minimal effects, e.g., skin changes; others manifest profound seizures and mental retardation. Tuberous sclerosis complex is caused by mutations in either the tuberous sclerosis complex 1 or 2 gene (coding for hamartin and tuberin, respectively). The tuberous sclerosis complex 1/tuberous sclerosis complex 2 protein dimer complex is a crucial inhibitory element in the mammalian target of rapamycin pathway, regulating cell growth and proliferation. Until recently, few options existed, other than surgery, for treating symptoms of tuberous sclerosis complex related to the growth of hamartomas. Increased understanding of the genetic cause of the disease and underlying dysregulation of the mammalian target of rapamycin pathway has led to clinical trials of mammalian target of rapamycin inhibitors, including sirolimus and everolimus. This review gives an overview of tuberous sclerosis complex and its molecular causes, and summarizes results from recent clinical trials of mammalian target of rapamycin inhibitors in patients with the disease.

Mammalian target of rapamycin (mTOR) inhibitors slow skin carcinogenesis, but impair wound healing.

BACKGROUND: Recent studies suggest that patients on mammalian target of rapamycin (mTOR) inhibitors experience a reduction in cutaneous carcinogenesis by an estimated 50% or more compared with calcineurin inhibitors. While randomized trials are running, organ transplant recipients are frequently switched from calcineurin inhibitors to mTOR inhibitors when cutaneous carcinogenesis increases. OBJECTIVES: To slow carcinogenesis in our patient, a heart transplant recipient with a neuropathic diabetic foot syndrome who had developed cutaneous carcinogenesis at a rate of more than 20 squamous cell carcinomas (SCC) annually. METHODS: The patient's immunosuppression was switched from the calcineurin inhibitor ciclosporin to the mTOR inhibitor everolimus. RESULTS: Carcinogenesis slowed to six SCC annually; however, he developed recalcitrant diabetic foot ulcers which were purely neuropathic and nonangiopathic, and a limb-threatening fistulating necrotic erysipelas of the right leg. Both sites responded poorly to antibiotic therapy, offloading and debridement. This skin fistula became chronic and some toes were at risk for minor amputation. In view of the propensity for mTOR inhibitors to impair would healing, immunosuppression was switched back to ciclosporin. All wounds healed rapidly, but skin carcinogenesis rose to former levels. CONCLUSIONS: This case impressively illustrates the clinical dilemma for mTOR inhibitor use where benefit in carcinogenesis is counterbalanced by impairment in wound healing. Changes in immunosuppressive regimens should thus be made on an individual basis with careful consideration of the relative risks.

Molecular targeted agents for gastric and gastroesophageal junction cancer.

Despite recent improvements in surgical techniques and chemotherapy, advanced cancers of the stomach and gastroesophageal junction (GEJ) continue to have poor clinical outcomes. However, molecules intimately related to cancer cell proliferation, invasion, and metastasis have been studied as candidates for molecular targeted agents. Target molecules, such as the epidermal growth factor receptor, vascular endothelial growth factor receptor, and P13k/Akt/mTor pathway, as well as the insulin-like growth factor receptor, c-Met pathways, fibroblast growth factor receptor, and other pathways are considered to be promising candidates for molecular targeted therapy for gastric and GEJ cancer. In this review we focus on the recent developments in targeting relevant pathways in these types of cancer.