C-kit Gene Research Articles

Amelanotic Melanoma-Biochemical and Molecular Induction Pathways.

Amelanotic melanoma (AM) is a subtype of hypomelanotic or completely amelanotic melanoma. AM is a rare subtype of melanoma that exhibits a higher recurrence rate and aggressiveness as well as worse surveillance than typical melanoma. AM shows a dysregulation of melanin production, cell cycle control, and apoptosis pathways. Knowing these pathways has an application in medicine due to targeted therapies based on the inhibiting elements of the abovementioned pathways. Therefore, we summarized and discussed AM biochemical and molecular induction pathways and personalized medicine approaches, clinical management, and future directions due to the fact that AM is relatively rare. AM is commonly misdiagnosed. Hence, the role of biomarkers is becoming significant. Nonetheless, there is a shortage of biomarkers specific to AM. BRAF, NRAS, and c-KIT genes are the main targets of therapy. However, the role of BRAF and KIT in AM varied among studies. BRAF inhibitors combined with MAK inhibitors demonstrate better results. Immune checkpoint inhibitors targeting CTLA-4 combined with a programmed death receptor 1 (PD-1) show better outcomes than separately. Fecal microbiota transplantation may overcome resistance to immune checkpoint therapy of AM. Immune-modulatory vaccines against indoleamine 2,3-dioxygenase (IDO) and PD ligand (PD-L1) combined with nivolumab may be efficient in melanoma treatment.

Unraveling Gastric and Small Intestine Gastrointestinal Stromal Tumors: A Review of Our Current Knowledge

Background: Gastrointestinal Stromal Tumors (GISTs) are characterized as round, well–defined mass lesions in the submucosal layer of the gastrointestinal (GI) tract. GISTs often present histological diversity and mutations in c-KIT and PDGFRA genes. Symptoms usually appear as abdominal pain, often accompanied by gastrointestinal bleeding or abdominal mass. The prognosis relies on tumor size, mitotic index, and different mutations, such as KIT mutations. There are a variety of diagnostic measures in the case of GISTs. However, it is important to note that ultrasound is the most common and reliable method for diagnosing gastric GISTs. The treatment methods followed vary from preoperative systemic therapy to surgical interventions. Depending on the type of GIST, professionals decide upon the best treatment plan for the patient. Objective: This review aims to inform the scientific community about the intricacies of gastric and small intestine GISTs to enhance understanding and improve patient management, with a particular focus on the importance of understanding and interpreting the unique microscopic histopathological findings of GISTs.

Artificial intelligence can be trained to predict c-KIT-11 mutational status of canine mast cell tumors from hematoxylin and eosin-stained histological slides.

Numerous prognostic factors are currently assessed histologically and immunohistochemically in canine mast cell tumors (MCTs) to evaluate clinical behavior. In addition, polymerase chain reaction (PCR) is often performed to detect internal tandem duplication (ITD) mutations in exon 11 of the c-KIT gene (c-KIT-11-ITD) to predict the therapeutic response to tyrosine kinase inhibitors. This project aimed at training deep learning models (DLMs) to identify MCTs with c-KIT-11-ITD solely based on morphology. Hematoxylin and eosin (HE) stained slides of 368 cutaneous, subcutaneous, and mucocutaneous MCTs (195 with ITD and 173 without) were stained consecutively in 2 different laboratories and scanned with 3 different slide scanners. This resulted in 6 data sets (stain-scanner variations representing diagnostic institutions) of whole-slide images. DLMs were trained with single and mixed data sets and their performances were assessed under stain-scanner variations (domain shifts). The DLM correctly classified HE slides according to their c-KIT-11-ITD status in up to 87% of cases with a 0.90 sensitivity and a 0.83 specificity. A relevant performance drop could be observed when the stain-scanner combination of training and test data set differed. Multi-institutional data sets improved the average accuracy but did not reach the maximum accuracy of algorithms trained and tested on the same stain-scanner variant (ie, intra-institutional). In summary, DLM-based morphological examination can predict c-KIT-11-ITD with high accuracy in canine MCTs in HE slides. However, staining protocol and scanner type influence accuracy. Larger data sets of scans from different laboratories and scanners may lead to more robust DLMs to identify c-KIT mutations in HE slides.

Induction of Thymus Atrophy and Disruption of Thymocyte Development by Fipronil through Dysregulation of IL-7-Associated Genes.

The susceptibility of the immune system to immunotoxic chemicals is evident, particularly in the thymus, a vital primary immune organ prone to atrophy due to exposure to toxicants. Fipronil (FPN), a widely used insecticide, is of concern due to its potential neurotoxicity, hepatotoxicity, and immunotoxicity. Our previous study showed that FPN disturbed the antigen-specific T-cell functionality in vivo. As T-cell lineage commitment and thymopoiesis are closely interconnected with the normal function of the T-cell-mediated immune responses, this study aims to further examine the toxic effects of FPN on thymocyte development. In this study, 4-week-old BALB/c mice received seven doses of FPN (1, 5, 10 mg/kg) by gavage. Thymus size, medulla/cortex ratio, total thymocyte counts, double-positive thymocyte population, and IL-7-positive cells decreased dose-dependently. IL-7 aids the differentiation of early T-cell precursors into mature T cells, and several essential genes contribute to the maturation of T cells in the thymus. Foxn1 ensures that the thymic microenvironment is suitable for the maturation of T-cell precursors. Lyl1 is involved in specifying lymphoid cells and maintaining T-cell development in the thymus. The c-Kit/SCF collaboration fosters a supportive thymic milieu to promote the formation of functional T cells. The expression of IL-7, IL-7R, c-Kit, SCF, Foxn1, and Lyl1 genes in the thymus was significantly diminished in FPN-treated groups with the concordance with the reduction of IL-7 signaling proteins (IL-7, IL-7R, c-KIT, SCF, LYL1, FOXO3A, and GABPA), suggesting that the dysregulation of T-cell lineage-related genes may contribute to the thymic atrophy induced by FPN. In addition, FPN disturbed the functionality of thymocytes with an increase of IL-4 and IFN-γ production and a decrease of IL-2 secretion after T-cell mitogen stimulation ex vivo. Collectively, FPN significantly deregulated genes related to T-cell progenitor differentiation, survival, and expansion, potentially leading to impaired thymopoiesis.

Understanding Gastric GIST: From Pathophysiology to Personalized Treatment.

Background: Gastric gastrointestinal stromal tumors (GISTs) represent a subset of gastrointestinal tumors predominantly found in the stomach. Despite their rarity, these tumors carry significant implications for patient health and management. GISTs are potentially malignant tumors with unpredictable progression. They originate from the interstitial cells of Cajal, which are positioned between the intramural neurons and the smooth muscle cells of the digestive tract. These tumors are characterized primarily by mutations in the c-Kit gene, as well as other mutations such as those in the platelet-derived growth factor receptor alpha (PDGFRA) gene. Methods: Our comprehensive search across five databases initially yielded 2976 articles. After eliminating 197 duplicates, we screened the titles and abstracts of 2779 articles, excluding 2692 for not meeting the inclusion criteria. During the full-text screening, 16 more articles were excluded. Ultimately, 71 papers met the inclusion criteria and were included in our analysis. Results: Due to differences in study designs, inclusion criteria for patients, and reported outcomes, a meta-analysis was not conducted. The accurate diagnosis of GIST is established through histopathological examination and immunohistochemistry. Histopathologically, GISTs are classified into three main types: spindle cell, epithelioid, and mixed. The therapeutic management of GIST involves surgery, endoscopic treatment, and chemotherapy. Conclusions: The prognosis for GIST patients depends on various factors, including risk category, disease stage, applied treatments, and recurrence post-treatment. A significant recent advancement comes from artificial intelligence, which can be increasingly involved in both the diagnosis and treatment of this tumor.

The effect of aerobic-resistance training on the population of cardiac multipotent cells, thickness, and diameter of the ventricular wall through the c-kit pathway in male rats during the growth stages

Background. The purpose of the present study was to investigate the effect of aerobic-resistance training on the population of cardiac multipotent cells, thickness, and diameter of the ventricular through the C-Kit pathway of male rats during the growth stages. Methods. Overall, 30 male Wistar rats in three age groups of 2 (n = 10), 8 (n = 10), and 96 (n = 10) weeks were accidentally divided into exercise and control groups. Resistance training programs (resistance ladder, 3 days a week) and aerobics (treadmill running, 3 days a week) were performed for 6 weeks. Hematoxylin-Eosin staining was done the heart tissue and histological images were prepared. Afterward, C-Kit gene expression was examined by the real-time polymerase chain reaction method. The statistical method of one-way analysis of variance (P ≥ 0.05) and Tukey’s test were used at a significant level (P ≥ 0.01). Results. The trained neonatal group had higher values in heart weight to body weight index, and the trained neonatal and trained young adult groups had higher values in left ventricular thickness (P ≥ 0.01). The decrease in left ventricular internal diameter in the trained young adult group was significant compared to the control group (P ≥ 0.01). There was a significant increase in C-Kit gene expression in trained young adult and trained old groups (P ≥ 0.01). Conclusion. Aerobic-resistance training can be an effective stimulus for increasing the number of cardiac stem cells and creating structural adaptations of the heart, including increasing thickness and ventricular diameter in neonatal and young adult groups. Practical Implications. Participation in aerobic-resistance training programs leads to the improvement of the cardiac structure and an increase in cardiac stem cells.

The effects of vitamin C and vitamin B12 on improving spermatogenesis in mice subjected to long-term scrotal heat stress.

Scrotal hyperthermia poses a significant threat to spermatogenesis and fertility in mammalian species. This study investigated the effects of vitamin B12 and vitamin C on spermatogenesis in adult male mice subjected to long-term scrotal hyperthermia. The rationale is based on the sensitivity of germ cells and epididymal sperm to increased scrotal temperatures. While various factors, both internal and external, can raise the testicular temperature, this study focused on the potential therapeutic roles of vitamins B12 and C. After inducing scrotal hyperthermia in mice, vitamin B12 and vitamin C were administered for 35 days. We assessed sperm parameters, serum testosterone levels, stereological parameters, the percentage of apoptotic cells, reactive oxygen species (ROS) levels, and glutathione (GSH) levels. Additionally, real-time polymerase chain reaction was used to analyze the expression of the c-kit, stimulated by retinoic acid gene 8 (Stra8), and proliferating cell nuclear antigen (Pcna) genes. Vitamin C was more effective than vitamin B12 in improving sperm parameters and enhancing stereological parameters. The study showed a significant decrease in apoptotic cells and a beneficial modulation of ROS and GSH levels following vitamin administration. Moreover, both vitamins positively affected the expression levels of the c-kit, Stra8, and Pcna genes. This research deepens our understanding of the combined impact of vitamins B12 and C in mitigating the effects of scrotal hyperthermia, providing insights into potential therapeutic strategies for heat stress-related infertility. The findings highlight the importance of considering vitamin supplementation as a practical approach to counter the detrimental effects of elevated scrotal temperatures on male reproductive health.

A canine mastocytoma with oncogenic c-kit activation by intra-exonic alternative splicing

We report a subcutaneous mastocytoma in a mid-aged Italian greyhound dog with a small 41 bp genomic deletion of the c-kit gene leading to skipping of the authentic 3′-splice junction of intron 10. The shift to an alternative splice junction in exon 11 leads to a mis-spliced in-frame mRNA transcript with a 27 bp deletion of exon 11 coding for 9 amino acids in the juxtamembrane negative regulatory domain of c-kit tyrosine kinase. In the tumor, c-kit was activated as revealed by more pronounced c-kit-regulated signaling by the PI3K/Akt and G-coupled receptor pathways. The same 9 amino acids deletion was reported in several human gastrointestinal stromal tumors (GIST) pointing to a remarkable similarity of c-kit activation by small deletions and aberrant splicing in humans and dogs, independent of exact sequence context, tumor type and location. Interestingly, the alternative splice junction in exon 11 has been conserved in Primates but less in other Orders with increased body temperature such as ruminants. We hypothesize that elevated body temperature has acted as evolutionary pressure to eliminate the alternative splice site at this hotspot. At a molecular level, hyperthermia may increase the frequency of small deletions in the c-kit gene by facilitating base slipping or hindering repair. An RT-qPCR assay was developed to detect c-kit alternative splicing in tumors and cell lines exposed to hyperthermia. The molecular mechanisms of tumorigenesis are discussed.

Caffeine attenuates spermatogenic disorders in mice with induced chronic scrotal hyperthermia.

Chronic scrotal hyperthermia (SHT) can lead to serious disorders of the male reproductive system, with oxidative stress playing a key role in the onset of these dysfunctions. Thus, we evaluated the impact of caffeine, a potent antioxidant, on cellular and tissue disorders in mice with chronic SHT. In this experimental study, 56 adult male NMRI mice were allocated into seven equal groups. Apart from the non-treated control group, all were exposed to heat stress. Two groups, termed "preventive" and "curative," were orally administered caffeine. The preventive mice began receiving caffeine immediately prior to heat exposure, while for the curative group, a caffeine regimen was initiated 15 consecutive days following cessation of heat exposure. Each treated group was subdivided based on pairing with a positive control (Pre/curative [Cur]+PC) or a vehicle (Pre/Cur+vehicle). Upon conclusion of the study, we assessed sperm characteristics, testosterone levels, stereological parameters, apoptosis, antioxidant and oxidant levels, and molecular markers. Sperm parameters, testosterone levels, stereological parameters, biochemical factors (excluding malondialdehyde [MDA]), and c-kit gene expression were significantly elevated in the preventive and curative groups, especially the former, relative to the other groups. Conversely, expression levels of the heat shock protein 72 (HSP72) and nuclear factor kappa beta (NF-κβ) genes, MDA levels, and apoptotic cell density were markedly lower in both caffeine-treated groups relative to the other groups, with more pronounced differences observed in the preventive group. Overall, caffeine attenuated cellular and molecular abnormalities induced by heat stress in the testis, particularly in the mice treated under the preventive condition.

Selective Recognition of c-KIT 1 G-Quadruplex by Structural Tuning of Heteroaromatic Scaffolds and Side Chains.

In this study, carbazole (MC) and dibenzofuran (MD) derivatives were synthesized to examine their effect on the biomolecular recognition of G-quadruplex (G4) targets. Biophysical studies revealed that MC-4, a carbazole derivative, exhibits a specific affinity and effectively stabilizes the c-KIT 1 G4. Molecular modeling suggests a stable interaction of MC-4 with the terminal G-tetrad of c-KIT 1 G4. Biological studies demonstrate that MC-4 efficiently enters cells, reduces c-KIT gene expression, and induces cell cycle arrest, DNA damage, and apoptosis in cancer cells. These findings demonstrate MC-4 as a selective c-KIT G4 ligand with therapeutic potential, providing insight into the structural basis of its anticancer mechanisms.

Estrone-Based Derivatives Stabilize the c-MYC and c-KIT G-Quadruplex DNA Structures.

G-rich sequences are present across the genome and can fold to form dynamic secondary structures, namely, G-quadruplexes (G4). These structures play a pivotal role in regulating numerous biological processes including replication, transcription, and translation. Therefore, targeting these structures using molecular scaffolds is an attractive approach to modulating their functions. Herein, we report the synthesis of three estrone-based derivatives (Est-1, Est-2, and Est-3) with a nonplanar core and a cationic alkyl side chain as G4 stabilizers. CD melting and polymerase stop assay results indicate that these ligands preferentially stabilize parallel c-MYC and c-KIT1 G4s over the other G4s and duplex DNAs. The ligand Est-3 shows cytotoxicity against cancer cell lines and effectively downregulates the c-KIT gene in HepG2 cell lines. Molecular modeling and dynamics studies showed that the ligand prefers stacking over the 5'-quartet of c-MYC G4 using the aromatic ring of the ligand. Overall, the findings of this study demonstrate that even G4 ligands can accommodate nonplanar scaffolds, which opens up new avenues for ligand design.

The role of heredity in cutaneous mastocytosis and C-KIT gene mutation

Introduction. Mastocytosis is a rare disease associated with the proliferation of clonal mast cells in the skin and other organs and systems. In the last decade, studies have appeared on the role of genetic factors in the development of the disease. According to their results, the mode of inheritance of mastocytosis was determined to be autosomal dominant with incomplete penetrance of the gene. Aim. To analyze the frequency of familial cases of mastocytosis and describe a familial case of monomorphic type maculopapular cutaneous mastocytosis (monoPPCM). Results. A family history was present in 6.7% of 341 children with mastocytosis. The article presents a description of the clinical, laboratory and instrumental features of monoPPCM in cousins (paternal kinship). The course of mastocytosis in a patient with the KIT D816V mutation in the peripheral blood was more severe than in her cousin without the mutation. Conclusion. The family case of monoMPCM presented in the article demonstrated the need for careful examination and dynamic monitoring of children with this pathology. The diagnosis of monomorphic (“adult”) type of MPCM is associated with a long course and the risk of developing systemic mastocytosis. Determining KIT mutations is necessary not only for prognosis, but also for developing a strategy for monitoring and treating the patient.

Molecular Characterisation and Outcomes of 363 Adolescent and Young Adults with AML in Saudi Arabia Risk Stratified By PCR and NGS-Based Testing

Introduction Acute Myeloid Leukaemia (AML) is characterised by cytogenetic (CGN) abnormalities and or mutations in one or more of a number of genes that allow risk stratification and guide treatment. The mutational landscape of patients from Saudi Arabia, which has a young population, has not been well characterised. One study indicates a higher rate of core binding factor and monosomies. Mutational analysis by Next generation sequencing (NGS) has not had widespread utilisation hampering the risk stratification of AML in the country. The more recent introduction of NGS panels has allowed more risk stratification. Here we analysed patients and characterised the CGN and molecular abnormalities. Methods Data were collected from 363 patients, and their cytogenetic and molecular results were reviewed. Patients were divided into 2 cohorts: Cohort A only had PCR-based testing diagnosed or treated at King Faisal Specialist Hospital and research centre - Riyadh. PCR testing included mutation analysis for FLT3, NPM1, CEBPA, c-KIT, IDH1, IDH2, WT1, DNMT3A, and JAK2; quantitative PCR for RUNX1-ETO in a subset of patients. Cohort B had PCR-based mutation testing in addition to the Next-Generation Sequencing (NGS) myeloid panel, which was Illumina-based or Ion Torrent. The panel comprises 23 hotspot genes, 17 entire genes, 29 fusion drivers, and five expression genes associated with haematological malignancies. We risk-stratified patients according to the most recent testing method available. Cohort A and Cohort B were risk-stratified, according to ELN risk classification 2017. Survival analysis for these patients was conducted. Results The median age for all patients was 39 years (13-89). PCR testing included mutation analysis for FLT3 (93.4%), NPM1 (90.4%), CEBPA (69.7%), c -KIT (54.3%), IDH1 (57%), IDH2 (57.9%), WT1 (61.2%), DNMT3A (54.5.5%), JAK2 (4.7%) and quantitative PCR for RUNX1- ETO fusion (13.2%). Cohort A comprised 262 (72.7%) patients who underwent PCR-based mutation testing only. Cohort B consisted of 101 (27.8%) patients who underwent PCR-based mutation testing in addition to NGS myeloid panel analysis. In the entire cohort of 363 patients, we found FLT3-ITD mutations in 85 patients (23.4%) and NPM1 mutations in 68 (18.7%). 36 patients (9.9%) harboured both FLT3-ITD and NPM1 mutations together. In Cohort A, FLT3-ITD detected 26.7% of patients, and 20.2% had NPM1 mutation, while 40% had no detectable mutations by conventional PCR. On the other hand, FLT3-ITD was detected in 14.9% of patients by both NGS and conventional PCR and in 14.9% of patients with NPM1. When comparing Cohort A and Cohort B, Cohort B had more mutations in genes that play an important role in myeloid malignancies, which might have better risk stratification and precision, including TP53 in 13.9% of patients and RUNX1 in 18.8% of patients and ASXL1 in 9.9% of patients. Moreover, NGS pick up more mutations in CEBPA, c-KIT, WT1, IDH1 and JAK2 genes compared to conventional PCR. Within cohort A, 9.2% of patients had normal cytogenetic testing results with no detectable mutations, whereas in cohort B, only 1% of patients had normal karyotype and molecular testing. Furthermore, six mutations were detected only by NGS but not PCR in FLT3-ITD, CEBPA, c-KIT, IDH2, WT1 and DNMT3A in 5.9% of patients. Cohorts A and B were also categorised into ELN risk groups using PCR, sequencing, and cytogenetics testing. It was found that patients at adverse risk had shorter overall survival compared to those at intermediate or favourable risk in both cohorts, with p-values of 0.030 and 0.0007, respectively (Figure 1). The use of NGS was found to be more effective than conventional testing in identifying patients with adverse risk, with a hazard ratio for death of 0.22 (95% CI, 0.08989-0.5732) compared to a hazard ratio of 0.66 (95% CI, 0.4352 -1.031) for conventional PCR testing. Conclusion In this study, we present the mutational profile of AML in young Saudi patients and identify certain frequent mutations in this population. The study presents the largest molecular profiling to our knowledge of this population. The study emphasises the need for integration of NGS to enhance risk stratification and precision, enable better characterisation of high-risk patients, and improve the potential for targeted treatments.

Incidence and Prevalence of Mastocytosis in Adults: A Danish Nationwide Register Study

Introduction: Mastocytosis is a heterogeneous chronic disease caused by a mutation in the cKIT gene that allows for uncontrolled proliferation, accumulation and activation of abnormal mast cells. Mastocytosis is divided into cutaneous mastocytosis (CM) and systemic mastocytosis (SM) in which abnormal mast cells are found in various tissues of the body. SM is further divided into the following five subtypes related to disease severity: indolent systemic mastocytosis (ISM), smoldering systemic mastocytosis (SSM), aggressive systemic mastocytosis (ASM), systemic mastocytosis with an associated hematologic neoplasm (SM-AHN) and mast cell leukemia (MCL). Mastocytosis is considered a rare disease with an incidence and prevalence previously found to be 0,89 per 100.000 and 9,59 per 100.000, respectively; however, recent improvements related to diagnostic methods could have led to an increased incidence and prevalence. Therefore, updated data is needed. Methods: This study is a retrospective nationwide register study including all adult (≥18 years) patients with mastocytosis in Denmark diagnosed between January 1 st 1997 and December 31 st 2021. The study was conducted using the Danish Civil Registration System to merge data from the National Patient Register (NPR), the Danish Pathology Register (DPR) and the Danish Cancer Register (DCR). The National Patient Register contain information on all inpatient and outpatient contacts and is considered complete as of 1995-2018. The Danish Pathology Register contain information about all biopsies and pathologic examinations in Denmark and is considered complete as of 1997 to 2021. The Danish Cancer Register contain information on all incidences of cancer in Denmark and is considered complete as of 1987-2021. Year of diagnosis was considered as the earliest date across all registers and patients were categorized as most severe subtype of mastocytosis. The registers did not allow for a categorization of SSM and therefore indolent mastocytosis were all categorized as ISM. Patients without a positive extracutaneous biopsy and who have never been examined with a bone marrow biopsy were classified as mastocytosis in the skin (MIS). Results: These data are the preliminary results of this study. 1627 patient were included (female 924, 56,8%). Mastocytosis in the skin was the most prevalent type of mastocytosis (774, 47,57%), followed by ISM (441, 27,11%), CM (222, 13,64%) and SM-AHN (179, 11%), More than 80% of patients with ASM had another hematologic neoplasm and were categorized as SM-AHN. Few patients were classified as ASM (4, 0,25%) and MCL (7, 0,43%). A positive bone marrow biopsy was found among 601 (36,94%) of the patients; however, 774 (47,57%) patients with mastocytosis were not examined with a bone marrow biopsy. The incidence rate of mastocytosis (all subtypes) was lowest in 2003 with an incidence of 0,74 per 100.000. Hereafter, the incidence increased until reaching the highest level in 2018 with an incidence of 2,77 per 100.000 (figure 1). The 25-year limited-duration prevalence as of 1 st January 2022 was 28,44 per 100.000. Conclusion: This nationwide register study provides updated data on the prevalence and incidence of mastocytosis in Denmark. The incidence rate was found to have an increasing trend until 2018 when it reached the highest value of 2,77 per 100.000. The prevalence was found to be 28,44 and thereby higher than previous studies have found. However, the true prevalence is potentially higher as the data for the years 2019-2021 solely relies on the pathology register. This is preliminary data, and the results will be updated when the NPR is complete for these years.Further analysis will be conducted using the Register of Laboratory Results for Research to evaluate blood tests regarding tryptase levels as well as to provide further information regarding KIT mutational status.

Thymic stromal lymphopoietin (TSLP) is a substrate for tryptase in patients with mastocytosis

Mastocytosis is a heterogeneous disease associated to uncontrolled proliferation and increased density of mast cells in different organs. This clonal disorder is related to gain-of-function pathogenic variants of the c-kit gene that encodes for KIT (CD117) expressed on mast cell membrane. Thymic stromal lymphopoietin (TSLP) is a pleiotropic cytokine, which plays a key role in allergic disorders and several cancers. TSLP is a survival and activating factor for human mast cells through the engagement of the TSLP receptor. Activated human mast cells release several preformed mediators, including tryptase. Increased mast cell-derived tryptase is a diagnostic biomarker of mastocytosis. In this study, we found that in these patients serum concentrations of TSLP were lower than healthy donors. There was an inverse correlation between TSLP and tryptase concentrations in mastocytosis. Incubation of human recombinant TSLP with sera from patients with mastocytosis, containing increasing concentrations of tryptase, concentration-dependently decreased TSLP immunoreactivity. Similarly, recombinant β-tryptase reduced the immunoreactivity of recombinant TSLP, inducing the formation of a cleavage product of approximately 10 kDa. Collectively, these results indicate that TSLP is a substrate for human mast cell tryptase and highlight a novel loop involving these mediators in mastocytosis.

Protective effects of epigallocatechin gallate in the mice induced by chronic scrotal hyperthermia

One of the most common complications of chronic scrotal hyperthermia (SHT) is a serious disorder in the male reproductive system. The most important factor in the occurrence of these disorders is oxidative stress. Currently, we investigated the effects of epigallocatechin gallate (EGCG), as a highly potent antioxidant, against cells and tissue disorders in mice affected by chronic SHT. Fifty-six male adult NMRI mice were allocated into seven equal groups. Except the non-treated (Control) group, six other groups were exposed to heat stress. Two treated groups including Preventive and Curative received oral administration of EGCG (50 mg/kg/day) starting immediately before heat exposure and fifteen consecutive days after the end of the heat exposure, respectively. For each treated group, two subgroups including positive control (Pre/Cur + PC groups) and vehicle (Pre/Cur + vehicle groups) were considered. At the end of the study, sperm characteristics, testosterone levels, stereological parameters, apoptosis, oxidant state, and molecular assessments were performed. We found that the sperm parameters, testosterone levels, the numerical density of spermatogonia, primary spermatocytes, spermatids, sertoli, leydig cells, and seminiferous tubules, biochemical factors (except MDA), and expression of c-kit gene were significantly higher in the Preventive and Curative groups, especially in Preventive ones, compared to other groups (P < 0.05). This is while expression of HSP72 and NF-κβ genes, MDA levels, as well as density of apoptotic cells considerably decreased in both EGCG-treated groups compared to other groups and it was more pronounced in Preventive ones (P < 0.05). Generally, EGCG attenuated cellular and molecular disorders induced by heat stress in the testis and it was more pronounced in Preventive status.

N6-methyl-2′-deoxyadenosine promotes self-renewal of BFU-E progenitor in erythropoiesis

Red blood cells supply the oxygen required for all human cells and are in demand for emerging blood-loss therapy. Here we identified N6-methyl-2'-deoxyadenosine (6mdA) as an agonist that promotes the hyperproliferation of burst-forming unit erythroid (BFU-E) progenitor cells. In addition, 6mdA represses the apoptosis of erythroid progenitor cells (EPCs). Combined use of with SCF and EPO enabled cultures of isolated BFU-E to be expanded up to 5,000-fold. Transcriptome analysis showed that 6mdA upregulates the expression of the EPC-associated factors c-Kit, Myb, and Gata2 and downregulates that of the erythroid maturation-related transcription factors Gata1, Spi1, and Klf1. Mechanistic studies suggested that 6mdA enhances and prolongs the activation of erythropoiesis-associated master gene c-Kit and its downstream signaling, leading to expansion and accumulation of EPCs. Collectively, we demonstrate that 6mdA can efficiently stimulate the EPC hyperproliferation and provide a new regenerative medicine recipe to improve exvivo generation of red blood cells.

Anaplastic lymphoma kinase expression in PDGFRA-mutated gastrointestinal stromal tumors probably correlates with poor prognosis

BackgroundAnaplastic lymphoma kinase (ALK) overexpression and gene alterations have been detected in several mesenchymal tumors, with significant implications for diagnosis, therapy and prognosis. However, few studies have investigated the correlation between ALK expression status and clinicopathological characteristics in patients with gastrointestinal stromal tumors (GISTs).MethodsA total of 506 GIST patients were enrolled. Sanger sequencing was employed to detect c-KIT and PDGFRA gene mutations. The tissue microarray (TMA) technique and immunohistochemistry were employed to identify the ALK (clone: 1A4 and D5F3) expression status in the tumor tissues. The ALK gene variants of IHC-positive cases were analyzed by fluorescence in situ hybridization (FISH) and next-generation sequencing (NGS). The clinicopathological data were analyzed using SPSS Statistics 26.0.ResultsAmong the 506 GIST patients, the c-KIT mutation accounted for 84.2% (426/506), followed by PDGFRA mutation (10.3%, 52/506), while the wild-type accounted for the least (5.5%, 28/506). ALK-positive expression was detected in PDGFRA-mutant GISTs (7.7%, 4/52) but negative for c-KIT-mutant or wild-type GISTs by IHC. Four ALK IHC-positive patients were all male. The tumors all occurred outside the stomach. The predominant patterns of growth were epithelioid (2/4), spindle (1/4), and mixed type (1/4). They were all identified as high-risk classification according to the National Institutes of Health (NIH) classification. Aberrant ALK mutations were not identified by DNA-based NGS except in one of the 4 cases with amplification by FISH.ConclusionOur study revealed 7.7% (4/52) of ALK expression in PDGFRA-mutant GISTs, indicating that molecular tests were required to rule out the possibility of PDGFRA-mutant GISTs when encountering ALK-positive mesenchymal tumors with CD117-negative or weakly positive in immunohistochemical staining.

A STUDY ON RETROSPECTIVE ANALYSIS OF GASTROINTESTINAL STROMA TUMOURS.

Introduction:.Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasms of the gastrointestinal (GI) tract. They are believed to originate from the interstitial cells of Cajal (ICCs) or from the precursors of ICCs. Most GISTs show an activating mutation in either the c-kit or platelet-derived growth factor receptor alpha (PDGFRA) gene. Tumor size, mitotic rate, and anatomic location correlate with potential malignancy and recurrence rate. The aim of our study is to Aim &amp; Objectivesobserve the demographic and clinical characteristics of GIST in our clinical environment.Method- 30 patients who are diagnosed with GIST managed during the period from Jun 2017 to July 2022 were reviewed in terms of demographics, clinical presentation, location of tumor, characteristics, management, histopathology, IHC analysis, post op follow up &amp; recurrence.The risk stratication in terms of size, mitotic index, site of tumour was observed &amp; classied using modied NIH classication. Results- Out of 30 cases male patient's- 73% (n- 22); female patients27%(n-8). Mean age was 60 years with a range of 44-81 years. Most common clinical presentation was abdominal mass, Abdominal pain. Commonly involved sites are stomach and small bowel.4 cases who underwent multiple organ resection 2 cases developed recurrence in which 1 underwent palliative Whipple's procedure and one was medically managed. GIST Conclusion- s are rare entities with a variety of clinical features, Common sites for GIST are stomach &amp; small intestine. Surgery is the main stay of management in GIST. Neo adjuvant therapy will help in down staging the tumour. Wedge resection &amp; resection &amp;anastomosis will be adequate for stomach in small bowel GIST. En-bloc resection should be considered if adjacent structures are involved. Overall GIST has favourable prognosis if diagnosed early

Characterization of cell line with dedifferentiated GIST-like features established from cecal GIST of familial GIST model mice.

Approximately 40 families with multiple gastrointestinal stromal tumors (GISTs) and germline c-kit gene mutations have been reported. Three knock-in mouse models have been generated, and all the models showed a cecal GIST. In the present study, we established a cell line derived from cecal GIST in a familial GIST model mouse with KIT-Asp818Tyr. Since the established cells showed spindle-shaped morphology with atypical nuclei, and since immunohistochemistry revealed that they were positive for α-SMA but negative for KIT, CD34 and desmin, the phenotypes of the cells were reminiscent of dedifferentiated GIST-like ones but not the usual GIST-like ones. Gene expression analysis showed that the cell line, designated as DeGISTL1 cell, did not express c-kit gene apparently, but highly expressed HSP90 families and glutaminase 1. Pathway analysis of the cells revealed that metabolic pathway might promote their survival and growth. Pimitespib, a heat shock protein 90α/β inhibitor, and Telaglenastat, a selective glutaminase 1 inhibitor, inhibited proliferation of DeGISTL1 cells and the combination of these showed an additive effect. DeGISTL1 cells might be a good model of dedifferentiated GISTs, and combination of Pimitespib and Telaglenastat could be a possible candidate for treatment strategy for them.