Molecular Genetic Landscape of Sclerosing Pneumocytomas

Author(s):  
Jennifer M Boland ◽  
Hee Eun Lee ◽  
Emily G Barr Fritcher ◽  
Jesse S Voss ◽  
Erik Jessen ◽  
...  

Abstract Objectives Sclerosing pneumocytomas are rare pulmonary neoplasms that are typically benign. However, rare patients experience progressive disease, and therapy targeting specific genetic underpinnings could be an attractive therapeutic option. Recent studies have found recurrent AKT 1 mutations in sclerosing pneumocytoma, but little is known about whether oncogenic fusion genes may also be present. Methods To better understand the genetic background, 10 sclerosing pneumocytomas were subjected to next-generation sequencing cancer mutation panel testing (n = 9) and/or RNA sequencing (n = 3). The patients were all women (average age, 47 years; range, 17-74 years). Results Eight patients had solitary sclerosing pneumocytomas, while one had two tumors, and one had many bilateral tumors. Recurrent mutations were noted in genes involved in the mTOR pathway, including AKT1, PIK3R1, and PTEN. AKT1 alterations were particularly common, present in 78%. No recurrent genetic fusions were identified. The patient in our study with multiple bilateral lesions was treated with the mammalian target of rapamycin (mTOR) inhibitor everolimus, with no objective radiographic evidence of treatment response after 4 months. Conclusions Our data further support that abnormal activation of the mTOR pathway is a consistent genetic event in sclerosing pneumocytoma. This warrants further exploration to determine if mTOR pathway inhibitors may be effective in patients with metastatic or recurrent disease.

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. A544-A544
Author(s):  
Jason Wang ◽  
Motoyasu Satou ◽  
Tae Tateno ◽  
Sarah Willette ◽  
Rui Zhe Yang ◽  
...  

Abstract Cushing’s disease (CD) is characterized by cortisol overproduction due to ACTH hypersecretion from a pituitary tumour (PT). With an incidence of approximately 1.2 to 2.4 cases per million per year, CD patients have higher rates of morbidity and mortality than the general population. Surgical management is currently the first therapeutic option. However, remission rates vary between studies, and patients may suffer from complications caused by hormonal abnormalities from remnant PT tissues, the surgery itself, as medical treatment options are limited. Macrophage migratory inhibitory factor (MIF) is a cytokine expressed in various tumors, including ACTH-producing PTs, and has been found to play a crucial role in tumorigenesis. Previous studies demonstrate that MIF regulates cell growth via the signal transducer and activator of transcription 3 (STAT3) pathway, the mammalian target of rapamycin (mTOR) pathway, and autophagy. Together, these indicate MIF as a potential therapeutic target for PTs. However, the role of MIF in ACTH-producing PTs remains unknown. Using mouse ACTH-producing PT cells, AtT-20 cells as a model, we established that MIF overexpression led to increased cell growth. In contrast, pharmacological MIF inhibition by 4-iodo-6-phenylpyrimidine (4-IPP) and (S,R)-3-(4-Hydroxyphenyl)-4,5-dihydro-5-isoxazole acetic acid (ISO-1) and genetic MIF downregulation by siRNA both suppressed cell viability and induced apoptosis, suggesting an anti-apoptotic role of MIF. Genetic MIF downregulation also increased the expression of apoptosis-inducible genes such as activating transcription factor 4 (ATF4) and C/EBP homologous protein (CHOP), and reduced ACTH production. However, pharmacological MIF inhibition had no effect on ACTH production, which suggests that the mechanism of pharmacological MIF inhibition may be different from MIF downregulation. Neither MIF upregulation nor downregulation affected cell signalling pathways such as the STAT3 pathway, the mTOR pathway, or autophagy. Our findings suggest that MIF inhibition can be a viable therapeutic approach for ACTH-producing PTs.


2017 ◽  
Vol 63 (3) ◽  
pp. 461-465
Author(s):  
Lev Bershteyn ◽  
Dmitriy Vasilev ◽  
Tatyana Poroshina ◽  
Igor Berlev

Increased frequency of endometrial cancer (EC) since the beginning of this century exceeds that of breast cancer and to a large extent can be attributed to dynamics of parameters, which characterize hormonal and metabolic status of ill women and molecular genetic landscape of transforming endometrium. During the past few years there are suggested several options for a personalized assessment of the risk of EC. The aim of this article is to propose and justify own version of this score with the idea of its further not only retrospective but also prospective testing both in relation to the risk of developing endometrial cancer as well as an additional marker helping to predict tumor response to treatment.


2020 ◽  
Vol 27 ◽  
Author(s):  
Naser-Aldin Lashgari ◽  
Nazanin Momeni Roudsari ◽  
Saeideh Momtaz ◽  
Negar Ghanaatian ◽  
Parichehr Kohansal ◽  
...  

: Inflammatory bowel disease (IBD) is a general term for a group of chronic and progressive disorders. Several cellular and biomolecular pathways are implicated in the pathogenesis of IBD, yet the etiology is unclear. Activation of the mammalian target of rapamycin (mTOR) pathway in the intestinal epithelial cells was also shown to induce inflammation. This review focuses on the inhibition of the mTOR signaling pathway and its potential application in treating IBD. We also provide an overview on plant-derived compounds that are beneficial for the IBD management through modulation of the mTOR pathway. Data were extracted from clinical, in vitro and in vivo studies published in English between 1995 and May 2019, which were collected from PubMed, Google Scholar, Scopus and Cochrane library databases. Results of various studies implied that inhibition of the mTOR signaling pathway downregulates the inflammatory processes and cytokines involved in IBD. In this context, a number of natural products might reverse the pathological features of the disease. Furthermore, mTOR provides a novel drug target for IBD. Comprehensive clinical studies are required to confirm the efficacy of mTOR inhibitors in treating IBD.


2010 ◽  
Vol 17 (4) ◽  
pp. 977-987 ◽  
Author(s):  
Luisella Righi ◽  
Marco Volante ◽  
Ida Rapa ◽  
Veronica Tavaglione ◽  
Frediano Inzani ◽  
...  

Among alternative therapeutic strategies in clinically aggressive neuroendocrine tumors (NETs) of the lung, promising results have been obtained in experimental clinical trials with mammalian target of rapamycin (mTOR) inhibitors, though in the absence of a proven mTOR signaling activation status. This study analyzed the expression of phosphorylated mTOR (p-mTOR) and its major targets, the ribosomal p70S6-kinase (S6K) and the eukaryotic initiation factor 4E-binding protein 1 (4EBP1) in a large series of 218 surgically resected, malignant lung NETs, including 24 metastasizing typical carcinoids, 73 atypical carcinoids, 60 large cell neuroendocrine carcinomas (LCNECs), and 61 small cell carcinomas (SCLCs). By immunohistochemistry, low-to-intermediate-grade tumors as compared with high-grade tumors showed higher levels of p-mTOR and phosphorylated S6K (p-S6K) (P<0.001), at variance with phosphorylated 4EBP1 (p-4EBP1), which was mainly expressed in LCNECs and SCLCs (P<0.001). The activated status of mTOR pathway was proved by the strong correlation of p-mTOR with p-S6K and somatostatin receptor(s). Western blot analysis of NET tumor samples confirmed such findings, and differential sensitivity to mTOR inhibition according to mTOR pathway activation characteristics was determined in two lung carcinoid cell lines in vitro. None of the investigated molecules had an impact on survival. However, in low-grade tumors, low p-mTOR expression correlated with lymph node metastases (P=0.016), recurrent disease, and survival (P=0.005). In conclusion, these data demonstrate a differential mTOR activation status in the spectrum of pulmonary NETs, possibly suggesting that mTOR pathway profiling might play a predictive role in candidate patients for mTOR-targeted therapies.


1999 ◽  
Vol 19 (3) ◽  
pp. 43-50 ◽  
Author(s):  
KK Giuliano ◽  
E Bloniasz ◽  
J Bell

We have no quantitative research data to document that these visits are actually helpful to patients in any measurable way, although we certainly hope to have some soon. However, observations of staff members and evaluations from participants in the program have been quite positive thus far. The program has been in place for more than 2 years, and about 30 pets have visited so far, including 28 dogs and 2 cats. Implementing a pet visitation program for critically ill patients affords healthcare providers the opportunity to offer a unique and humanistic therapeutic intervention to appropriate patients. Although it is a time-consuming endeavor, it has been well received by those patients and families that have participated in pet visits. Critically ill patients are often denied many simple pleasures because they are in physiological crisis. Such patients experience loneliness, isolation, depression, and lack of emotional support. Pet visitation is one way to address these common problems of ICU patients. For this reason, pet visitation will remain a therapeutic option for the support of our critically ill patients.


2013 ◽  
Vol 38 (8) ◽  
pp. 862-869 ◽  
Author(s):  
Brittany A. Edgett ◽  
Melanie L. Fortner ◽  
Arend Bonen ◽  
Brendon J. Gurd

This study examined changes in the expression of translation initiation regulatory proteins and mRNA following both an acute bout of endurance exercise and chronic muscle contractile activity. Female Sprague Dawley rats ran for 2 h at 15 m·min−1 followed by an increase in speed of 5 m·min−1 every 5 min until volitional fatigue. The red gastrocnemius muscle was harvested from nonexercised animals (control; n = 6) and from animals that exercised either immediately after exercise (n = 6) or following 3 h of recovery from exercise (n = 6). Compared with control, ribosomal protein S6 (rpS6) mRNA was elevated (p < 0.05) at both 0 h (+32%) and 3 h (+47%). Both a catalytic subunit of eukaryotic initiation factor 2B (eIF2Bε) (+127%) and mammalian target of rapamycin (mTOR) mRNA (+44%) were increased at 3 h, compared with control. Phosphorylation of mTOR (+40%) and S6 kinase 1 (S6K1) (+266%) were increased immediately after exercise (p < 0.05). Female Sprague Dawley rats also underwent chronic stimulation of the peroneal nerve continuously for 7 days. The red gastrocnemius muscle was removed 24 h after cessation of the stimulation. Chronic muscle stimulation increased (p < 0.05) mTOR protein (+74%), rpS6 (+31%), and eukaryotic initiation factor 2α (+44%, p = 0.069), and this was accompanied by an increase in cytochrome c (+31%). Increased resting phosphorylation was observed for rpS6 (+51%) (p < 0.05) but not for mTOR or eukaryotic initiation factor 4E binding protein 1. These experiments demonstrate that both acute and chronic contractile activity up-regulate the mTOR pathway and mitochondrial content in murine skeletal muscle. This up-regulation of the mTOR pathway may increase translation efficiency and may also represent an important control point in exercise-mediated mitochondrial biogenesis.


Hematology ◽  
2011 ◽  
Vol 2011 (1) ◽  
pp. 543-549 ◽  
Author(s):  
Timothy Graubert ◽  
Matthew J. Walter

Abstract Myelodysplastic syndromes (MDS) are a heterogenous group of hematologic malignancies characterized by clonal expansion of BM myeloid cells with impaired differentiation. The identification of recurrent mutations in MDS samples has led to new insights into the pathophysiology of these disorders. Of particular interest is the recent recognition that genes involved in the regulation of histone function (EZH2, ASXL1, and UTX) and DNA methylation (DNMT3A, IDH1/IDH2, and TET2) are recurrently mutated in MDS, providing an important link between genetic and epigenetic alterations in this disease. The mechanism by which these mutated genes contribute to disease pathogenesis is an active area of research, with a current focus on which downstream target genes may be affected. Recent advances from sequencing studies suggest that multiple mutations are required for MDS initiation and progression to acute myeloid leukemia (AML). The past several years have yielded many new insights, but the complete genetic landscape of MDS is not yet known. Moreover, few (if any) of the findings are sufficiently robust to be incorporated into routine clinical practice at this time. Additional studies will be required to understand the prognostic implications of these mutations for treatment response, progression to AML, and survival.


2011 ◽  
Vol 39 (2) ◽  
pp. 451-455 ◽  
Author(s):  
Carlos Garcia-Echeverria

Substantial drug discovery efforts have been devoted, over the last few years, to identifying and developing mTOR (mammalian target of rapamycin) kinase modulators. This has resulted in a number of mTOR inhibitors with different mechanisms of action and/or distinct protein and lipid kinase selectivity profiles. As briefly reviewed in the present paper, these compounds have provided us with a better understanding of the roles of mTOR and other phosphoinositide 3-kinase/mTOR pathway components in human cancer biology, and a few of them have already demonstrated clinical benefit in cancer patients.


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