Project description:Primary gastrointestinal (GI) T-cell lymphoma is an infrequent and aggressive disease. However, rare indolent clonal T-cell proliferations in the GI tract have been described. We report 10 cases of GI involvement by an indolent T-cell lymphoproliferative disease, including 6 men and 4 women with a median age of 48 years (range, 15-77 years). Presenting symptoms included abdominal pain, diarrhea, vomiting, food intolerance, and dyspepsia. The lesions involved oral cavity, esophagus, stomach, small intestine, and colon. The infiltrates were dense, but nondestructive, and composed of small, mature-appearing lymphoid cells. Eight cases were CD4(-)/CD8(+), 1 was CD4(+)/CD8(-), and another was CD4(-)/CD8(-). T-cell receptor-? chain gene rearrangement identified a clonal population in all 10 cases. There was no evidence of STAT3 SH2 domain mutation or activation. Six patients received chemotherapy because of an initial diagnosis of peripheral T-cell lymphoma, with little or no response, whereas the other 4 were followed without therapy. After a median follow-up of 38 months (range, 9-175 months), 9 patients were alive with persistent disease and 1 was free of disease. We propose the name "indolent T-LPD of the GI tract" for these lesions that can easily be mistaken for intestinal peripheral T-cell lymphoma, and lead to aggressive therapy.
Project description:BACKGROUND:Post-transplant lymphoproliferative disorder (PTLD) of T cell type has been rarely reported. Accurate diagnosis of this life-threatening rare form of PTLD is important for the treatment strategy. CASE PRESENTATION:A 7-year-old boy had severe diarrhea and weight loss progressively at 7?years post-living donor liver transplantation (LDLT) for biliary atresia. Endoscopy in the gastrointestinal (GI) tract revealed multiple erosions and ulcer lesions with prominent intraepithelial lymphocytosis in the duodenum and terminal ileum. Immunohistochemical examination demonstrated that these accumulated lymphocytes mainly comprised small- to medium-sized T cells expressing CD3, CD4, CD5, CD7, and CD103, but lacking CD8, CD56, and Epstein-Barr virus-encoded small RNAs. In addition, T cell receptor ? gene rearrangement was detected by polymerase chain reaction analysis. Comprehensively, the lesions were best interpreted as post-transplant indolent T cell lymphoproliferative disorder (LPD) of the intestine. Clinical remission was achieved by reducing the immunosuppressant. CONCLUSION:A rarely reported indolent type of T cell LPD in post-LDLT was diagnosed by direct inspection and histological investigation. Although the histological classification and therapeutic strategy for post-transplant indolent T cell LPD have not been established, reducing immunosuppression allowed complete remission in our case. To prevent the incidence of PTLD and de novo malignancy, developing a methodology to set a proper dose of immunosuppressant is required.
Project description:In an attempt to assess potential treatment options, whole-genome and transcriptome sequencing were performed on a patient with an unclassifiable small lymphoproliferative disorder. Variants from genome sequencing were prioritized using a combination of comparative variant distributions in a spectrum of lymphomas, and meta-analyses of gene expression profiling. In this patient, the molecular variants that we believe to be most relevant to the disease presentation most strongly resemble a diffuse large B-cell lymphoma (DLBCL), whereas the gene expression data are most consistent with a low-grade chronic lymphocytic leukemia (CLL). The variant of greatest interest was a predicted NOTCH2-truncating mutation, which has been recently reported in various lymphomas.
Project description:PurposeFlavopiridol downmodulates antiapoptotic proteins associated with resistance to fludarabine and rituximab and is effective against p53-mutated chronic lymphocytic leukemia (CLL). We conducted a phase I study of flavopiridol, fludarabine, and rituximab (FFR) in patients with mantle-cell lymphoma (MCL), indolent B-cell non-Hodgkin's lymphomas (B-NHL), and CLL to determine the activity of FFR.Patients and methodsTherapy included fludarabine 25 mg/m(2) intravenously (IV) days 1 to 5 and rituximab 375 mg/m(2) day 1 every 28 days for 6 cycles. We administered flavopiridol 50 mg/m(2) by 1-hour IV bolus (IVB) day 1 (n = 15); day 1 to 2 (n = 6); 20 mg/m(2) 30-minute IVB + 20 mg/m(2) 4-hour IV infusion (n = 3); or 30 mg/m(2) + 30 mg/m(2) (n = 14).ResultsThirty-eight patients (median age, 62 years) with MCL (n = 10); indolent B-NHL including follicular (n = 9), marginal zone (n = 4), lymphoplasmacytic (n = 1), or small lymphocytic lymphoma (n = 3); and CLL (n = 11), were enrolled. Twenty-two patients were previously untreated; 16 had received one to two prior therapies. Two patients in cohort 2 developed grade 3 dose-limiting toxicity (seizures, renal insufficiency). The median number of treatment cycles was 4, with cytopenias (n = 10) and fatigue (n = 3) the most common reasons for early discontinuation. Overall response rate was 82% (complete response, 50%; unconfirmed complete response, 5%; partial response, 26%), including 80% of patients with MCL (median age, 68; seven complete responses, one partial response). Median progression-free survival (PFS) was 25.6 months. Median PFS of patients with nonblastoid variant MCL (n = 8) was 35.9 months.ConclusionFFR was active in MCL, indolent B-NHL, and CLL and should be studied for older patients with MCL who are not candidates for aggressive chemotherapy.
Project description:Dysregulated crosstalk between different signaling pathways contributes to tumor development, including resistance to cancer therapy. In the present study, we found that the mitogen-activated extracellular signal-regulated kinase (MEK) inhibitor trametinib failed to suppress the proliferation of PANC-1 and MGC803 cells by activating the Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway, while the JAK2 inhibitor fedratinib failed to inhibit the growth of the PANC-1 cells upon stimulation of extracellular signal-regulated kinase (ERK) signaling. In particular, the most prominent enhancement of the anti-proliferative effect resulted from the concurrent blockage of the JAK2/STAT3 and ERK signaling pathways. Furthermore, the combination of the two inhibitors resulted in a reduced tumor burden in mice. Our evidence suggests novel crosstalk between JAK2/STAT3 and ERK signaling in gastric cancer (GC) and pancreatic ductal adenocarcinoma (PDAC) cells and provides a therapeutic strategy to overcome potential resistance in gastrointestinal cancer.
Project description:Objectives:T cells play an essential role in controlling the development of B-cell lymphoproliferative disorders (BLPDs), but the dysfunction of T cells in BLPDs largely remains elusive. Methods:Using multiplexed flow cytometry, we quantified all major subsets of CD4+ helper T cells (Th) and CD8+ cytotoxic T cells (Tc) in 94 BLPD patients and 66 healthy controls. Statistics was utilised to rank T-cell signatures that distinguished BLPDs from healthy controls and differentially presented between indolent and aggressive categories. Results:By comparing with healthy controls, we found that the indolent but not aggressive type of BLPDs demonstrated a high degree of T-cell activation, showing the increase in type I helper T (Th1) cells and follicular B-helper T (Tfh) cells, both of which strongly associated with the enhanced differentiation of exhaustion-like effector cytotoxic CD8+ T cells expressing PD-1 (Tc exhaustion-like) in indolent BLPDs. Random forest modelling selected a module of T-cell immune signatures best performing binary classification of all BLPD patients. This signature module was composed of low naïve Th cells and high Th1, Tfh and Tc exhaustion-like cells which efficiently identified > 85% indolent cases and was, therefore, assigned as the Indolent Dominant Module of T-cell immune signature. In indolent BLPD patients, a strong bias towards such signatures was found to associate with clinical characteristics of worse prognosis. Conclusion:Our study identified a prominent signature of T-cell dysregulation specifically for indolent BLPDs, suggesting Th1, Tfh and Tc exhaustion-like cells represent potential prognostic biomarkers and targets for immunotherapies.
Project description:The intestinal immune system, which must ensure appropriate immune responses to both pathogens and commensal microflora, comprises innate lymphoid cells and various T-cell subsets, including intra-epithelial lymphocytes (IELs). An example of innate lymphoid cells is natural killer cells, which may be classified into tissue-resident, CD56bright NK-cells that serve a regulatory function and more mature, circulating CD56dim NK-cells with effector cytolytic properties. CD56bright NK-cells in the gastrointestinal tract give rise to indolent NK-cell enteropathy and lymphomatoid gastropathy, as well as the aggressive extranodal NK/T cell lymphoma, the latter following activation by EBV infection and neoplastic transformation. Conventional CD4+ TCRαβ+ and CD8αβ+ TCRαβ+ T-cells are located in the lamina propria and the intraepithelial compartment of intestinal mucosa as type 'a' IELs. They are the putative cells of origin for CD4+ and CD8+ indolent T-cell lymphoproliferative disorders of the gastrointestinal tract and intestinal T-cell lymphoma, NOS. In addition to such conventional T-cells, there are non-conventional T-cells in the intra-epithelial compartment that express CD8αα and innate lymphoid cells that lack TCRs. The central feature of type 'b' IELs is the expression of CD8αα homodimers, seen in monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL), which primarily arises from both CD8αα+ TCRαβ+ and CD8αα+ TCRγδ+ IELs. EATL is the other epitheliotropic T-cell lymphoma in the GI tract, a subset of which arises from the expansion and reprograming of intracytoplasmic CD3+ innate lymphoid cells, driven by IL15 and mutations of the JAK-STAT pathway.
Project description:The cholinergic anti-inflammatory pathway is a physiological mechanism that inhibits cytokine production and minimizes tissue injury during inflammation. Previous investigations revealed that cholinergic stimulation (via cholinergic agonists and vagus nerve stimulation) suppresses endothelial cell activation and leukocyte recruitment. The purpose of this study was to investigate the mechanisms by which cholinergic agonists (e.g., nicotine and GTS-21) regulate endothelial cell activation. Specifically, we examined the effects of cholinergic agonists on IL-6-mediated endothelial cell activation through the JAK2/STAT3 signaling pathway. Treatment of macrovascular human umbilical vein endothelial cells (HUVECs) and microvascular endothelial cells (MVECs) with the cholinergic agonists nicotine and GTS-21 significantly reduced IL-6-mediated monocyte chemoattractant protein-1 (MCP-1) production and ICAM-1 expression which are regulated through the JAK2/STAT3 pathway. We found that treatment of endothelial cells with cholinergic agonists significantly reduced STAT3 activation by phosphorylation and DNA binding. The inhibition of STAT3 phosphorylation was reversed by sodium orthovanadate, an inhibitor of tyrosine phosphatases, as well as by NSC-87877 suggesting a SHP1/2-dependent mechanism. Further investigations showed that cholinergic agonists reduced the phosphorylation of JAK2, an upstream component of the JAK2/STAT3 pathway. Finally, we observed that nicotine and GTS-21 treatment decreased levels of SOCS3 (suppressor of cytokine signaling; a regulator of the inflammatory activity of IL-6) in activated endothelial cells. These data demonstrate that cholinergic agonists suppress IL-6-mediated endothelial cell activation through the JAK2/STAT3 pathway. Our results have significant implications for better understanding the therapeutic potential of cholinergic agonists for treating IL-6 mediated inflammatory conditions.
Project description:BackgroundMaspin (SERPINB5) is a potential tumor suppressor gene with pleiotropic biological activities, including regulation of cell proliferation, death, adhesion, migration and gene expression. Several studies indicate that nuclear localization is essential for maspin tumor suppression activity. We have previously shown that the EGFR activation leads to maspin nuclear localization in MCF-10A cells. The present study investigated which EGFR downstream signaling molecules are involved in maspin nuclear localization and explored a possible role of cell-cell contact in this process.MethodsMCF-10A cells were treated with pharmacological inhibitors against EGFR downstream pathways followed by EGF treatment. Maspin subcellular localization was determined by immunofluorescence. Proteomic and interactome analyses were conducted to identify maspin-binding proteins in EGF-treated cells only. To investigate the role of cell-cell contact these cells were either treated with chelating agents or plated on different cell densities. Maspin and E-cadherin subcellular localization was determined by immunofluorescence.ResultsWe found that PI3K-Akt and JAK2-STAT3, but not MAP kinase pathway, regulate EGF-induced maspin nuclear accumulation in MCF-10A cells. We observed that maspin is predominantly nuclear in sparse cell culture, but it is redistributed to the cytoplasm in confluent cells even in the presence of EGF. Proteomic and interactome results suggest a role of maspin on post-transcriptional and translation regulation, protein folding and cell-cell adhesion.ConclusionsMaspin nuclear accumulation is determined by an interplay between EGFR (via PI3K-Akt and JAK2-STAT3 pathways) and cell-cell contact. Video Abstract.
Project description:Hemobilia, a rare form of upper gastrointestinal bleeding (UGIB), is a potentially fatal complication that usually occurs after iatrogenic hepatobiliary trauma. However, hemobilia is clinically challenging to diagnose and often gets too late to diagnose. We herein report a case of recurrent hemobilia due to hepatic artery pseudoaneurysm (HAP) that was initially misdiagnosed as gastrointestinal tract bleeding. However, the patient was treated successfully with percutaneous coil occlusion of the pseudoaneurysm. This case illustrates that hemobilia can present as a mimic of gastrointestinal tract bleeding, but this is often difficult to diagnose at first glance and often misleads clinicians, especially emergency physicians, into making an incorrect diagnosis. Familiarity with the clinical features of hemobilia can help raise clinical suspicion and facilitate the early diagnosis and treatment of hemobilia.