Severe hemorrhagic colitis caused by dasatinib in Philadelphia chromosome-positive acute lymphoblastic leukemia

Recurrent Gastrointestinal Hemorrhage in Children with Philadelphia-Positive B-Cell Acute Lymphoblastic Leukemia Treated with Dasatinib: Case Reports

Dasatinib, a second-line tyrosine kinase inhibitor (TKI), has been widely used in chronic myeloid leukemia (CML) and Philadelphia-positive B-cell acute lymphoblastic leukemia (Ph + B-ALL). Although dasatinib has been well tolerated, side effects including hemorrhage are not rare. Cases of bleeding disorders ultimately result in thrombocytopenia, but platelet aggregation dysfunction induced by dasatinib has also been demonstrated in Ph + B-ALL and CML patients. We report three Chinese children with Ph + B-ALL who received a combination treatment of chemotherapy and dasatinib and developed gastrointestinal bleeding several months later. The platelet count and clotting tests were normal, and these patients presented with dasatinib-induced platelet dysfunction. These findings reveal that physicians should be aware of and carefully monitor for side effects, including bleeding disorders.

Dasatinib-induced immune mediated-thrombotic thrombocytopenic purpura

Most commonly seen side effects with Tyrosine kinase inhibitors (TKI's) are hematologic toxicities. Besides, with dasatinib autoimmune side effects can be seen. Thrombotic thrombocytopenic purpura (TTP) is a life- threatening disease that can be related to various causes mainly autoimmune disorders or antineoplastic drugs. Few cases of TKI associated secondary thrombotic microangiopathies (TMA) have been reported in literature. Most of cases were diagnosed as hemolytic uremic syndrome (HUS) rather than TTP. Herein, we describe a 37-year-old CML patient who was diagnosed as immune-mediated TTP related to dasatinib.

Dasatinib-Induced T-Cell-Mediated Colitis: A Case Report and Review of the Literature

Dasatinib is a potent inhibitor of the altered tyrosine kinase activity in disease states associated with BCR/ABL1. This agent has been shown to exhibit broad off-target kinase inhibition and immunomodulating properties. These effects may be responsible for dasatinib's unique side effects including a distinctive form of hemorrhagic colitis. We report a case of hemorrhagic colitis associated with dasatinib use in a patient with chronic myelogenous leukemia. Colon biopsies at the time of symptomatic colitis confirmed CD3+CD8+ T cell infiltration. The process rapidly resolved following drug discontinuation, but relapsed when rechallenged with a reduced dose of dasatinib. Colitis did not recur when the patient was treated with an alternative agent. A literature review of prior cases involving dasatinib-induced T-cell mediated colitis provides insight into commonalities that may facilitate the recognition and management of this entity. Most incidences occurred after a 3-month drug exposure and may be accompanied by large granular lymphocytes. The process uniformly resolves within a few days following drug discontinuation and will generally recur in a shorter period of time if the drug is reintroduced. Most patients will require an alternative agent, although select patients could be continued on dasatinib if other options are limited.

The efficacy of tyrosine kinase inhibitor dasatinib on colonic mucosal damage in murine model of colitis

BACKGROUND AND OBJECTIVE

Ulcerative colitis is an inflammatory condition of the colon in the gastrointestinal system. Currently, the most potent medications used for ulcerative colitis produce no response in 20-30% of cases. There is a need for more efficient and reliable medications. Tyrosine kinase inhibitors have shown efficacy in some inflammatory diseases. Although dasatinib, a tyrosine kinase inhibitor, suppresses proinflammatory cytokines in colonic tissue, there are a few cases of hemorrhagic colitis with dasatinib. There is no study investigating the effect of dasatinib on experimental colitis. We aimed to investigate the effect of dasatinib in a colitis model induced with acetic acid in our study.

METHODS

In the study, 24 male Sprague-Dawley rats randomly distributed into 4 groups of 6 rats each as control, dasatinib, colitis and dasatinib+colitis groups. For colitis induction, 4% acetic acid was used. Sacrificing of the rats was performed on the seventh day. Disease activity, morphologic and histological injury, superoxide dismutase, myeloperoxidase and malondialdehyde activity, TNFα and CD3 expression were assessed in colonic tissue.

RESULTS

Apart from malondialdehyde, significant difference in all parameters between the control and colitis groups was determined. Difference between the colitis and colitis+dasatinib groups was not significant in only weight loss and biochemical parameters. Though dasatinib does not fully resolve the changes in colitis, there was significant regression.

CONCLUSIONS

Dasatinib decreased the inflammation in a rodent model of colitis. It may be provide this effect by the suppression of TNFα. Dasatinib may be one of the treatment options for ulcerative colitis.

A Case of Dasatinib-Induced Hemorrhagic Colitis Diagnosed by the Lymphocyte Transformation Test in a Chronic Myeloid Leukemia Patient

Dasatinib is an effective treatment option for patients diagnosed with Philadelphia chromosome positive chronic myeloid leukemia and who are non-responsive or intolerant to imatinib treatment. Dasatinib, however, is associated with various adverse effects and on rare occasions, may cause hemorrhagic colitis. We report the case of a 68-year-old male patient with dasatinib-induced hemorrhagic colitis, the first such case in Korea. Endoscopic biopsy of the transverse colon demonstrated non-specific inflammatory changes only. Cessation of dasatinib led to the resolution of symptoms, while reintroduction of the therapy led to the recurrence of his bloody diarrhea. To clarify the association between dasatinib and hemorrhagic colitis, the lymphocyte transformation test (LTT) was performed. The LTT result sustained a relatively high proliferation activity in the affected patient compared with almost no proliferation activity in normal control.

Dasatinib-Induced CMV Hepatitis in an Immunocompetent Patient: A Rare Complication of a Common Drug

Dasatinib is a common anticancer drug used in the treatment of leukemia. Several side effects have been reported, the most common being myelosuppression, diarrhea, edema, and nausea. Three papers have been published reporting hepatic side effects of dasatinib treatment. A rare side effect of dasatinib treatment is reactivation of latent cytomegalovirus (CMV) infection. Never before has dasatinib therapy shown to be the cause of CMV hepatitis in an immunocompetent patient. We present a case of an immunocompetent patient who was treated with the standard dose of dasatinib therapy and subsequently developed CMV hepatitis. Well-known side effects of dasatinib therapy are understood and documented; unknown adverse drug reactions can occur and should be monitored for. This is a significant finding given the high rate of CMV seropositivity in the general population.

Lyn deficiency leads to increased microbiota-dependent intestinal inflammation and susceptibility to enteric pathogens

The Lyn tyrosine kinase governs the development and function of various immune cells, and its dysregulation has been linked to malignancy and autoimmunity. Using models of chemically induced colitis and enteric infection, we show that Lyn plays a critical role in regulating the intestinal microbiota and inflammatory responses as well as protection from enteric pathogens. Lyn(-/-) mice were highly susceptible to dextran sulfate sodium (DSS) colitis, characterized by significant wasting, rectal bleeding, colonic pathology, and enhanced barrier permeability. Increased DSS susceptibility in Lyn(-/-) mice required the presence of T but not B cells and correlated with dysbiosis and increased IFN-γ(+) and/or IL-17(+) colonic T cells. This dysbiosis was characterized by an expansion of segmented filamentous bacteria, associated with altered intestinal production of IL-22 and IgA, and was transmissible to wild-type mice, resulting in increased susceptibility to DSS. Lyn deficiency also resulted in an inability to control infection by the enteric pathogens Salmonella enterica serovar Typhimurium and Citrobacter rodentium. Lyn(-/-) mice exhibited profound cecal inflammation, bacterial dissemination, and morbidity following S. Typhimurium challenge and greater colonic inflammation throughout the course of C. rodentium infection. These results identify Lyn as a key regulator of the mucosal immune system, governing pathophysiology in multiple models of intestinal disease.

Lyn activity protects mice from DSS colitis and regulates the production of IL-22 from innate lymphoid cells

Intestinal homeostasis requires a complex balance of interactions between diverse resident microbial communities, the intestinal epithelium, and the underlying immune system. We show that the Lyn tyrosine kinase, a critical regulator of immune cell function and pattern-recognition receptor (PRR) responses, has a key role in controlling gastrointestinal inflammation. Lyn⁻/⁻ mice were highly susceptible to dextran sulfate sodium (DSS)-induced colitis, whereas Lyn gain-of-function (Lyn(up)) mice exhibited attenuated colitis during acute and chronic models of disease. Lyn(up) mice were hypersensitive to lipopolysaccharide (LPS), driving enhanced production of cytokines and factors associated with intestinal barrier function, including interleukin (IL)-22. Oral administration of LPS was sufficient to protect antibiotic-treated Lyn(up) but not wild-type mice from DSS, highlighting how Lyn-dependent changes in the nature/magnitude of PRR responses can impact intestinal health. Furthermore, protection from DSS-induced colitis and increased IL-22 production in response to LPS did not depend on the adaptive immune system, with increased innate lymphoid cell-derived IL-22 correlating with Lyn activity in dendritic cells. These data reveal a key role for Lyn in the regulation of innate immune responses and control of intestinal inflammation.

Dasatinib promotes the expansion of a therapeutically superior T-cell repertoire in response to dendritic cell vaccination against melanoma

Dasatinib (DAS) is a potent inhibitor of the BCR-ABL, SRC, c-KIT, PDGFR, and ephrin tyrosine kinases that has demonstrated only modest clinical efficacy in melanoma patients. Given reports suggesting that DAS enhances T cell infiltration into the tumor microenvironment, we analyzed whether therapy employing the combination of DAS plus dendritic cell (DC) vaccination would promote superior immunotherapeutic benefit against melanoma. Using a M05 (B16.OVA) melanoma mouse model, we observed that a 7-day course of orally-administered DAS (0.1 mg/day) combined with a DC-based vaccine (VAC) against the OVA_257–264 peptide epitope more potently inhibited tumor growth and extended overall survival as compared with treatment with either single modality. The superior efficacy of the combinatorial treatment regimen included a reduction in hypoxic-signaling associated with reduced levels of immunosuppressive CD11b⁺Gr1⁺ myeloid-derived suppressor cells (MDSC) and CD4⁺Foxp3⁺ regulatory T (Treg) populations in the melanoma microenvironment. Furthermore, DAS + VAC combined therapy upregulated expression of Type-1 T cell recruiting CXCR3 ligand chemokines in the tumor stroma correlating with activation and recruitment of Type-1, vaccine-induced CXCR3⁺CD8⁺ tumor-infiltrating lymphocytes (TILs) and CD11c⁺ DC into the tumor microenvironment. The culmination of this bimodal approach was a profound “spreading” in the repertoire of tumor-associated antigens recognized by CD8⁺ TILs, in support of the therapeutic superiority of combined DAS + VAC immunotherapy in the melanoma setting.

Dasatinib-induced haemorrhagic colitis in chronic myeloid leukaemia (CML) in blast crisis

We report a rare case of haemorrhagic colitis attributed to dasatinib therapy in a 47-year-old African-American woman who was diagnosed with extramedullary T-lymphoblastic transformation of chronic myeloid leukaemia. The patient received intensive chemotherapy and dasatinib 100 mg/day. After achieving complete cytogenetic and major molecular response after 9 months of therapy, she developed bloody diarrhoea and pancytopenia. Colonoscopy showed inflammation of the descending colon and histopathology revealed patchy increase in intraepithelial lymphocytes. Dasatinib was stopped with prompt resolution of diarrhoea. The current literature suggests that there is an association in a subset of patients on dasatinib between clonal T-cell lymphocytosis in the peripheral blood and developing colitis and pleural effusions. These patients had a good response to dasatinib as did our patient. Our patient illustrates a unique disease presentation along with a rare drug adverse event.

Haemorrhagic colitis caused by dasatinib

Gastrointestinal bleeding appears to be a common adverse event associated with dasatinib therapy. Here we present a case of a 59-year-old man with chronic myeloid leukaemia (CML) developing the rarest complication of haemorrhagic colitis with dasatinib therapy which resolved rapidly after treatment withdrawal.

Controversies in the treatment of CML in children and adolescents: TKIs versus BMT?

Chronic myeloid leukemia (CML) is a relatively rare hematopoietic malignancy in the pediatric and adolescent population. This makes it difficult to perform clinic trials that can define the best therapeutic option when considering the impact of tyrosine kinase inhibitors (TKIs) versus the established approach of allogeneic hematopoietic cell transplantation (HCT). With the relatively low toxicity of TKIs, there are little data regarding when HCT or long-term TKI therapy is a better option. There are even less data regarding the duration of TKI treatment in the pediatric CML in chronic phase (CML-CP) patients who may receive over 60 years of therapy. As children and adolescent are treated for longer times with TKIs, it has become clear that toxicities may make long-term TKI therapy less attractive compared to allogeneic HCT. HCT has the long-term complications of growth failure, infertility, chronic graft-versus-host disease (GVHD), metabolic syndrome, and secondary malignancies, whereas prolonged TKIs may cause growth failure, hepatic, and cardiac complications. Moreover, HCT is a potentially curative intervention, whereas TKI is not curative, requiring prolonged exposure. In this article, we discuss the relative merit of the 2 therapeutic approaches and recommend that all children and adolescents with CML-CP should initially be treated with imatinib and maintained with TKI therapy indefinitely if there is a good response. We recommend that allogeneic HCT with an HLA-identical sibling donor or closely matched unrelated donor be considered for patients with treatment failure or recurrence after receiving salvage second-generation TKI treatment. We also conclude that randomized international trials are urgently needed to evaluate the best therapies for pediatric CML.

Philadelphia chromosome-positive acute lymphoblastic leukemia in children: new and emerging treatment options

Philadelphia chromosome-positive (Ph(+)) acute lymphoblastic leukemia (ALL) in children and adolescents has, until recently, been considered one of the poorest-risk subgroups of ALL. With chemotherapy alone, only 20-30% of children with Ph(+) ALL are cured. Allogeneic hematopoietic cell transplantation in first complete remission cures 60% of patients with a closely matched donor. Although targeted tyrosine kinase inhibitors (TKIs) have limited activity against Ph(+) ALL as a single agent, they have been evaluated in combination with chemotherapy with promising results. The early results of Children's Oncology Group trial AALL0031 have shown 88% 3-year event-free survival for Ph(+) patients treated with intensive chemotherapy plus continuous-dosing imatinib. This suggests that chemotherapy plus TKIs may be the initial treatment of choice for Ph(+) ALL in children. However, the numbers are small in this trial and confirmatory results are not yet available from the European Intergroup Study on Post Induction Treatment of Philadelphia Positive Acute Lymphoblastic Leukaemia with Imatinib trial. Additional issues include determining the most effective TKI (imatinib, dasatinib or nilotinib) and the most effective, least toxic chemotherapy backbone. The experience of adding a targeted agent such as a TKI to the standard chemotherapy regimen suggests that this strategy might be applied to other ALL subtypes to achieve both increased efficacy and decreased toxicity.