Fusion variations of neurotrophic receptor tyrosine kinase (NTRK) are oncogenic drivers in various solid tumors such as breast cancer, salivary gland carcinoma, infant fibrosarcoma, etc. Gene rearrangements involving NTRK1/2/3 lead to constitutive activation of the tropomyosin receptor kinase (TRK) domain, and the expressed fusion proteins drive tumor growth and survival. NTRK fusions are estimated to occur at a frequency of approximately 0.1% to 1% in non-small cell lung cancer (NSCLC). Epidermal growth factor receptor (EGFR) mutations are prevalent in NSCLC, but the frequency of EGFR G719A mutation is relatively low (about 2%), and EGFR mutations are typically mutually exclusive with NTRK fusion variants. The study presented the first documented case of lung adenocarcinoma harboring both EGFR G719A mutation and LMNA-NTRK1 fusion. A review of the literature was conducted to elucidate the role of NTRK fusion mutations in NSCLC and their relationship with EGFR mutations, aiming to enhance the understanding of NTRK fusion mutations in NSCLC.
.
Humans ; Adenocarcinoma/genetics* ; Adenocarcinoma of Lung ; ErbB Receptors/genetics* ; Lamin Type A/genetics* ; Lung Neoplasms/genetics* ; Mutation ; Oncogene Proteins, Fusion/genetics* ; Receptor, trkA/metabolism*

Objective: To investigate the clinicopathological, immunohistochemical and molecular genetic characteristics of gastric carcinoma with NTRK-rearrangement/amplification. Methods: The clinicopathological data of gastric carcinoma cases with NTRK-rearrangement/amplification diagnosed from January 2011 to September 2020 at the Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, China, were collected. The clinicopathological, immunophenotypic and molecular pathological features were analyzed. The relevant literature was reviewed. Results: There were 4 cases of gastric carcinoma with NTRK-rearrangement/amplification. All 4 patients were male, aged 57-67 years (average, 63 years). Tumor sizes ranged from 3.5 to 5.2 cm (average, 4.8 cm). All tumors were in the antrum. All 4 patients underwent radical gastrectomy and were followed up after the surgery. Morphologically, all tumors showed histological features with enteroblastic-differentiated gastric carcinoma. Tumor cells showed predominantly tubular/papillary architecture, with conspicuous vesicular nuclei and pale staining or transparent cytoplasm. Immunohistochemistry showed pan-TRK expression in all cases, with various degrees of positivity in the cytoplasm. All cases were subject to NTRK1/2/3 detection using fluorescence in situ hybridization. There were NTRK translocations in 2 cases and NTRK amplifications in 2 cases. These cases were further verified by RNAseq next generation sequencing which confirmed that NTRK1 gene translocation (TPM3-NTRK1) and NTRK2 gene translocation (NTRK2-SMCHD1) occurred in two cases, respectively. Conclusions: NTRK mutation occurs less frequently in gastric cancer. In this study, the cases mainly occur in the antrum. The morphology has the characteristics of enteroblastic differentiation. The tumors have unique histological, immunophenotypic and molecular characteristics, which require much attention from pathologists to effectively guide clinicians to choose the best treatment.
Humans ; Male ; Female ; Receptor, trkA/genetics* ; Stomach Neoplasms/surgery* ; In Situ Hybridization, Fluorescence ; Biomarkers, Tumor/genetics* ; Translocation, Genetic ; Carcinoma ; Oncogene Proteins, Fusion/genetics* ; Chromosomal Proteins, Non-Histone/genetics*

Humans ; Clinical Relevance ; Receptor, trkA/genetics* ; Neoplasms ; Digestive System Neoplasms/genetics* ; Oncogene Proteins, Fusion/genetics* ; Gene Fusion

Humans ; Receptor, trkA/genetics* ; Neoplasms/genetics* ; Biomarkers, Tumor ; Gene Rearrangement ; Oncogene Proteins, Fusion/genetics*

Objective: To investigate the frequency of neurotrophic tyrosine receptor kinase (NTRK) gene variations in papillary thyroid carcinoma (PTC) and to analyze the feasibility of detecting tropomyosin receptor kinase (TRK) proteins using immunohistochemistry (IHC) to predict the fusion variation of NTRK. Methods: A cohort of 848 PTC cases was collected at the Department of Pathology, Shenzhen People's Hospital from June 2017 to June 2020. The expression levels of TRK proteins were detected using IHC in 848 PTC samples, and the DNA-based next generation sequencing (NGS) was performed to detect NTRK rearrangements in 150 PTCs. Results: There were 242 males and 606 females, with an age range of 9-83 years. In 120 cases with TRK expression detected by IHC, 13 cases were confirmed to harbor a NTRK gene fusion by NGS. The frequency of NTRK fusion in PTC was 1.5% (13/848). The sensitivity and specificity of TRK-IHC positivity for screening NTRK fusion in PTC were 100% and 21.9%, respectively. The specificity of weak-, moderate- and strong-positive stains of TRK IHC were 23.8%, 76.9% and 93.8%, respectively. The specificity of NTRK gene fusion was predicted to increase with the enhanced intensity of IHC staining. In BRAF V600E negative PTC samples, the specificity of weak-and moderate-positive stains of TRK IHC increased to 62.5% and 96.8%, respectively. Seven NTRK fusion partners were found in the PTC, including EML4, ETV6, CDH1, GJD2, TPR, TFG and SQSTM1. Conclusions: There is a low variation frequency of NTRK gene fusion in PTC. TRK IHC can be used as a screening method for NTRK fusion variation in PTC. The specificity of TRK IHC predicting NTRK fusion can be further enhanced by increasing the cutoff value of the positive cell number and staining intensity of TRK-IHC staining, or being combined with BRAF V600E negativity.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Child ; Female ; Gene Fusion ; Humans ; Immunohistochemistry ; Male ; Middle Aged ; Proto-Oncogene Proteins B-raf/genetics* ; Receptor Protein-Tyrosine Kinases/genetics* ; Receptor, trkA/genetics* ; Thyroid Cancer, Papillary/genetics* ; Thyroid Neoplasms/pathology* ; Young Adult

OBJECTIVE: To observe the effect of electroacupuncture (EA) at "Zusanli" (ST 36) on duodenal mast cells, nerve growth factor (NGF) and neurotrophic tyrosine kinase receptor type 1 (NTRK1), and to explore the mechanism of electroacupuncture at Zusanli (ST 36) on functional dyspepsia (FD). METHODS: Sixty SPF-grade 10-day-old SD rats were randomly divided into a normal group, a model group, a ketotifen group and an EA group, 15 rats in each group. The FD model was prepared by iodoacetamide combined with rat tail clamping method in the model group, the ketotifen group and the EA group. The rats in the ketotifen group were injected intraperitoneally with ketotifen (1 mg•kg^-1•d^-1) for 7 days; the rats in the EA group were treated with EA at bilateral "Zusanli" (ST 36), with disperse-dense wave, frequency of 2 Hz/50 Hz and intensity of 0.5 mA, 20 min each time, once a day for 14 days. The gastric emptying rate and small intestinal propulsion rate in each group were observed; the morphology of duodenal mucosa was observed by HE staining; the toluidine blue staining was used to observe the number and degranulation of mast cells in duodenal mucosa; the protein and mRNA expressions of NGF, NTRK1 in duodenum were detected by Western blot and real-time PCR; the level of interleukin-1β (IL-1β) in duodenum was measured by ELISA. RESULTS: Compared with the normal group, the gastric emptying rate and small intestinal propulsion rate in the model group were decreased (P<0.01); compared with the model group, the gastric emptying rate and small intestinal propulsion rate in the ketotifen group and the EA group were increased (P<0.01); the small intestinal propulsion rate in the EA group was higher than that in the ketotifen group (P<0.01). In the model group, local defects in duodenal mucosa were observed with a small amount of inflammatory cell infiltration; no obvious abnormality was found in duodenal mucosa of the other groups. Compared with the normal group, the mast cells of duodenal mucosa in the model group were increased significantly with significant degranulation; compared with the model group, the mast cells of duodenal mucosa in the ketotifen group and the EA group were decreased significantly, and the degranulation was not obvious. Compared with the normal group, the protein and mRNA expressions of NGF, NTRK1 as well as the level of IL-1β in duodenum in the model group were increased (P<0.01); compared with the model group, the protein and mRNA expressions of NGF, NTRK1 as well as the levels of IL-1β in duodenum in the ketotifen group and the EA group were decreased (P<0.01, P<0.05); compared with the ketotifen group, the mRNA expression of NGF, as well as the protein and mRNA expressions of NTRK1 in duodenum in the EA group were decreased (P<0.05, P<0.01). CONCLUSION EA at "Zusanli" (ST 36) could inhibit the activation of duodenal mast cells and regulate the expressions of NGF and its receptor to improve the low-grade inflammatory response of duodenum, resulting in treatment effect on FD.
Acupuncture Points ; Animals ; Duodenum/metabolism* ; Dyspepsia/therapy* ; Electroacupuncture ; Ketotifen ; Mast Cells/metabolism* ; Nerve Growth Factor/metabolism* ; RNA, Messenger ; Rats ; Rats, Sprague-Dawley ; Receptor, trkA/genetics*

The neurotrophin receptor kinase (NTRK) gene encodes neurotrophic factor receptor tyrosine kinase (NTRK), which plays an important role in the development and function of the nervous system. NTRK gene fusion mutation results in the production of chimeric NTRK proteins, which have carcinogenic potential through constitutive activation or overexpression. NTRK gene fusion mutation can lead to a special type of wild type gastrointestinal stromal tumor (GIST), whose clinical manifestations and treatment are completely different from other types of GIST. This fusion mutation can be detected clinically by a variety of methods, including tumor DNA and RNA sequencing and immunohistochemical staining. In patients with NTRK fusion positive tumors, NTRK inhibitors such as larotrectinib and entrectinib have shown good antitumor efficacy, with clinical response rates as high as 75%. Therefore, there is a need to improve the recognition and detection of fuch patients and to improve their prognosis by individualized and precise treatment with TRK inhibitors.
Gastrointestinal Stromal Tumors/genetics* ; Gene Fusion ; Humans ; Neoplasms ; Nerve Growth Factors ; Protein Kinase Inhibitors ; Receptor, trkA/genetics* ; Receptors, Nerve Growth Factor/genetics*

OBJECTIVETo screen for mutations of NTRK1 gene in a Chinese family affected with congenital insensitivity to pain with anhidrosis (CIPA).

METHODSGenomic DNA was extracted from the proband and her family members. All of the 17 exons and intron-exon boundaries of the NTRK1 gene were analyzed by direct Sanger sequencing. For the deletional mutation, the PCR products were subjected to T-A cloning and sequencing to verify the mutation.

RESULTSNTRK1 gene analysis revealed that proband has carried a c.1786C>T (p.Arg596*) nonsense mutation inherited from her mother and a novel deletional mutation c.1928-2028+23del from her father. Her elder brother only carried the deletional mutation.

CONCLUSIONThe diagnosis of CIPA relied on typical clinical symptoms of no pain, anhidrosis and intellectual disability and detection of the biallelic NTRK1 mutations. The novel deletional mutation has enriched the spectrum of NTRK1 mutations.

Child, Preschool ; DNA Mutational Analysis ; Exons ; Female ; Hereditary Sensory and Autonomic Neuropathies ; diagnosis ; genetics ; Humans ; Mutation ; Receptor, trkA ; genetics

OBJECTIVETo observe the effect of Draconis Sanguis-containing serum on the expressions of NGF, BDNF, CNTF, LNG-FR, TrkA, GDNF, GAP-43 and NF-H in Schwann cells, and investigate the possible mechanism of Draconis Sanguis to promote peripheral nerve regeneration.

METHODSD rats were randomly divided into 2 groups: the Draconis Sanguis group (orally administered with Draconis Sanguis-containing balm solution) and the blank group (equivoluminal balm) to prepare Draconis Sanguis-containing serum and blank control serum. Schwann cells were extracted from double sciatic nerves of three-day-old SD rats, divided into 2 groups: the Draconis Sanguis group and the blank control group, and respectively cultured with 10% Draconis Sanguis-containing serum or blank control serum. The mRNA expressions of NGF, BDNF, CNTF and other genes in Schwann cells were measured by RT-PCR analysis 48 hours later.

RESULTMost of the Schwann cells were bipolar spindle and arranged shoulder to shoulder or end to end under the microscope and identified to be positive with the immunocytochemical method. To compare with the blank group, mRNA expressions of NGF, LNGFR, GDNF and GAP-43 significantly increased (P < 0.01). Whereas that of BDNF decreased significantly (P < 0.05), and so did that of TrkA, CNTF (P < 0.01), with no remarkable difference in NF-H-mRNA.

CONCLUSIONTraditional Chinese medicine Draconis Sanguis may show effect in nerve regeneration by up-regulating mRNA expressions of NGF, LNGFR, GDNF and GAP-43 and down-regulating mRNA expressions of TrkA, BDNF and CNTF.

Animals ; Arecaceae ; chemistry ; Brain-Derived Neurotrophic Factor ; genetics ; metabolism ; Cells, Cultured ; Ciliary Neurotrophic Factor ; genetics ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; GAP-43 Protein ; genetics ; metabolism ; Gene Expression ; drug effects ; Glial Cell Line-Derived Neurotrophic Factor ; genetics ; metabolism ; Male ; Nerve Growth Factor ; genetics ; metabolism ; Nerve Regeneration ; drug effects ; Neurofilament Proteins ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley ; Receptor, trkA ; genetics ; metabolism ; Schwann Cells ; drug effects ; physiology ; Serum ; chemistry

OBJECTIVETo screen for mutations in the neurotrophic tyrosine kinase receptor type 1 (NTRK1) gene in a Chinese family affected with congenital insensitivity to pain with anhidrosis (CIPA).

METHODSWith informed consent obtained, peripheral blood samples were obtained from the patient and his family members. Seventeen coding exons and intron-exon boundaries of the NTRK1 gene were amplified with PCR and analyzed by direct sequencing.

RESULTSA novel mutation c.2086_2087insC (p.Arg696 fsx) was identified in exon 16 of the NTRK1 gene in the proband. This insertion has caused open reading frame shifting and a premature termination has occurred just one codon downstream. Truncation of 72 amino acids at the C terminus has wiped out part of the tyrosine kinase domain (TKD) of the protein. Both of the proband's parents and two grandmothers have carried the c.2086_2087insC (p.Arg696 fsx) mutation. No mutation was found in the NTRK1 gene of other siblings.

CONCLUSIONMutation analysis of the NTRK1 gene has been carried out in a Chinese family affected with CIPA, and a novel NTRK1 gene mutation was identified.

Base Sequence ; Child, Preschool ; DNA Mutational Analysis ; Exons ; genetics ; Hereditary Sensory and Autonomic Neuropathies ; genetics ; Humans ; Male ; Mutation ; Polymerase Chain Reaction ; Receptor, trkA ; genetics