[Retracted] Tanshinone IIA enhances the inhibitory effect of imatinib on proliferation and motility of acute leukemia cell line TIB‑152 in vivo and in vitro by inhibiting the PI3K/AKT/mTOR signaling pathway

Following the publication of the above article, a concerned reader drew to the Editor's attention that the Transwell cell invasion assay data featured in Figs. 2D and 4E, certain of the tumor images in Fig. 5A and the TUNEL assay data in Fig. 5C were strikingly similar to data appearing in different form in other articles written by different authors at different research institutes that had either already been published elsewhere prior to the submission of this paper to Oncology Reports, or which under consideration for publication at around the same time (some papers of which have been retracted). In view of the fact that certain of these data had already apparently been published prior to the submission of this article for publication, the Editor of Oncology Reports has decided that this paper should be retracted from the Journal. The authors were asked for an explanation to account for these concerns, but the Editorial Office did not receive a reply. The Editor apologizes to the readership for any inconvenience caused. [Oncology Reports 43: 503‑515, 2020; DOI: 10.3892/or.2019.7453].

Involvement of BCR::ABL1 in laminin adhesion of Philadelphia chromosome-positive acute lymphoblastic leukemia through upregulation of integrin α6

BACKGROUND

Adhesion of cancer cells to extracellular matrix laminin through the integrin superfamily reportedly induces drug resistance. Heterodimers of integrin α6 (CD49f) with integrin β1 (CD29) or β4 (CD104) are major functional receptors for laminin. Higher CD49f expression is reportedly associated with a poorer response to induction therapy in childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Moreover, a xenograft mouse model transplanted with primary BCP-ALL cells revealed that neutralized antibody against CD49f improved survival after chemotherapy.

AIMS

Considering the poor outcomes in Philadelphia chromosome (Ph)-positive ALL treated with conventional chemotherapy without tyrosine kinase inhibitors, we sought to investigate an involvement of the laminin adhesion.

METHODS AND RESULTS

Ph-positive ALL cell lines expressed the highest levels of CD49f among the BCP-ALL cell lines with representative translocations, while CD29 and CD104 were ubiquitously expressed in BCP-ALL cell lines. The association of Ph-positive ALL with high levels of CD49f gene expression was also confirmed in two databases of childhood ALL cohorts. Ph-positive ALL cell lines attached to laminin and their laminin-binding properties were disrupted by blocking antibodies against CD49f and CD29 but not CD104. The cell surface expression of CD49f, but not CD29 and CD104, was downregulated by imatinib treatment in Ph-positive ALL cell lines, but not in their T315I-acquired sublines. Consistently, the laminin-binding properties were disrupted by the imatinib pre-treatment in the Ph-positive ALL cell line, but not in its T315I-acquired subline.

CONCLUSION

BCR::ABL1 plays an essential role in the laminin adhesion of Ph-positive ALL cells through upregulation of CD49f.

Targeting mitochondrial bioenergetics by combination treatment with imatinib and dichloroacetate in human erythroleukemic K‑562 and colorectal HCT‑116 cancer cells

Tumor malignant cells are characterized by dysregulation of mitochondrial bioenergetics due to the 'Warburg effect'. In the present study, this metabolic imbalance was explored as a potential target for novel cancer chemotherapy. Imatinib (IM) downregulates the expression levels of SCΟ2 and FRATAXIN (FXN) genes involved in the heme‑dependent cytochrome c oxidase biosynthesis and assembly pathway in human erythroleukemic IM‑sensitive K‑562 chronic myeloid leukemia cells (K‑562). In the present study, it was investigated whether the treatment of cancer cells with IM (an inhibitor of oxidative phosphorylation) separately, or together with dichloroacetate (DCA) (an inhibitor of glycolysis), can inhibit cell proliferation or cause death. Human K‑562 and IM‑chemoresistant K‑562 chronic myeloid leukemia cells (K‑562R), as well as human colorectal carcinoma cells HCT‑116 (+/+p53) and (‑/‑p53, with double TP53 knock-in disruptions), were employed. Treatments of these cells with either IM (1 or 2 µM) and/or DCA (4 mΜ) were also assessed for the levels of several process biomarkers including SCO2, FXN, lactate dehydrogenase A, glyceraldehyde‑3‑phosphate dehydrogenase, pyruvate kinase M2, hypoxia inducing factor‑1a, heme oxygenase‑1, NF‑κB, stem cell factor and vascular endothelial growth factor via western blot analysis. Computational network biology models were also applied to reveal the connections between the ten proteins examined. Combination treatment of IM with DCA caused extensive cell death (>75%) in K‑562 and considerable (>45%) in HCT‑116 (+/+p53) cultures, but less in K‑562R and HCT‑116 (‑/‑p53), with the latter deficient in full length p53 protein. Such treatment, markedly reduced reactive oxygen species levels, as measured by flow‑cytometry, in K‑562 cells and affected the oxidative phosphorylation and glycolytic biomarkers in all lines examined. These findings indicated, that targeting of cancer mitochondrial bioenergetics with such a combination treatment was very effective, although chemoresistance to IM in leukemia and the absence of a full length p53 in colorectal cells affected its impact.

Treatment and follow-up of children with chronic myeloid leukaemia in chronic phase (CML-CP) in the tyrosine kinase inhibitor (TKI) era-Two decades of experience from the Tata Memorial Hospital paediatric CML (pCML) cohort

Tyrosine kinase inhibitors (TKIs) have drastically improved the outcomes of pCML (paediatric CML) but data on long-term off-target toxicities of TKIs in children are scarce. In this single-centre, retrospective cum prospective study of pCML in chronic phase, we report our experience of treating 173 children with imatinib and following them for long-term toxicities. Mean (SD) time to attain CHR, CCyR and MMR were 3.05 (2.1), 10.6 (8.4) and 43.4 (31.8) months respectively. DMR was not attained in 59 (34%) patients at last follow-up. Ten patients were switched to second-generation TKIs (2G-TKIs; nilotinib = 1/dasatinib = 9) due to poor/loss in response, of which seven had kinase domain mutations. Three patients progressed to the blastic phase. At a median follow-up of 84 (3-261) months, the 5-year EFS and OS for the entire cohort were 96.9% (95% CI: 93.4-100) and 98.7% (95% CI: 96.9-100) respectively. Screening for long-term toxicities revealed low bone density and hypovitaminosis D in 70% and 80% respectively. Other late effects included short stature (27%), delayed puberty (15%), poor sperm quality (43%) and miscellaneous endocrinopathies (8%). Children younger than 5 years at diagnosis were more susceptible to growth and endocrine toxicities (p = 0.009). Regular monitoring for long-term toxicities, timely intervention and trial of discontinuation whenever feasible are likely to improve the long-term outlook of pCML.

Primary EGIST of the greater omentum - a rare presentation

Extragastrointestinal stromal tumors (EGISTs) are rare mesenchymal neoplasms, which develop in the retroperitoneum, mesentery, and omentum, lacking continuity to the stomach or intestines. Authors hereby present a female patient with a large heterogeneous abdominal mass as a case of an omental EGIST. A 46-year-old woman was referred to our hospital due to an insidious enlargement and colicky pain in the right iliac fossa. Abdominal palpation revealed a voluminous, freely mobile, and non-pulsatile mesoabdominal bulge expanding to the hypogastrium. On exploratory midline laparotomy, the tumor was densely fused to the greater omentum, not connected to the stomach, without gross involvement of adjacent structures. The large mass was completely excised after adequate mobilization. Immunohistochemical techniques showed strong and diffuse expression of WT1, actin and DOG-1, as well as multifocal c-KIT marking. Mutational study concluded a double mutation of KIT exon 9 and a mutation of PDGFRA exon 18. The patient was submitted to adjuvant treatment with imatinib mesylate 800 mg/day. Despite an extremely diverse presentation, omental EGISTs often remain clinically silent for a long time having enough space to grow before becoming symptomatic. These tumors have a consistent pattern of metastasis that typically spares lymph nodes unlike epithelial gut neoplasms. Surgery remains the preferred treatment for non-metastatic EGISTs of the greater omentum. It is possible that DOG-1 will supplant KIT as the leading marker in the future. The scarcity of knowledge on omental EGISTs implies a close monitoring of these patients to detect local relapse or distant metastasis.

CX‑5461 potentiates imatinib‑induced apoptosis in K562 cells by stimulating KIF1B expression

The selective RNA polymerase I inhibitor CX-5461 has been shown to be effective in treating some types of leukemic disorders. Emerging evidence suggests that combined treatments with CX-5461 and other chemotherapeutic agents may achieve enhanced effectiveness as compared with monotherapies. Currently, pharmacodynamic properties of the combination of CX-5461 with tyrosine kinase inhibitors remain to be explored. The present study tested whether CX-5461 could potentiate the effect of imatinib in the human chronic myeloid leukemia cell line K562, which is p53-deficient. It was demonstrated that CX-5461 at 100 nM, which was non-cytotoxic in K562 cells, potentiated the pro-apoptotic effect of imatinib. Mechanistically, the present study identified that the upregulated expression of kinesin family member 1B (KIF1B) gene might be involved in mediating the pro-apoptotic effect of imatinib/CX-5461 combination. Under the present experimental settings, however, neither CX-5461 nor imatinib alone exhibited a significant effect on KIF1B expression. Moreover, using other leukemic cell lines, it was demonstrated that regulation of KIF1B expression by imatinib/CX-5461 was not a ubiquitous phenomenon in leukemic cells and should be studied in a cell type-specific manner. In conclusion, the results suggested that the synergistic interaction between CX-5461 and imatinib may be of potential clinical value for the treatment of tyrosine kinase inhibitor-resistant chronic myeloid leukemia.

Development of a simultaneous quantification method of imatinib and sunitinib and their main metabolites and its application in patients with gastrointestinal stromal tumor

Correlations between plasma concentrations of imatinib and sunitinib with efficacy and toxicity have been established. It is crucial to develop a sensitive and precise method for determining the plasma concentrations of imatinib and sunitinib, along with their active metabolites, to facilitate therapeutic drug monitoring and individualized therapy. Plasma samples were separated on an Agilent ZORBAX SB-C18 chromatographic column using gradient elution. Quantification was performed using a mass spectrometer equipped with electrospray ionization in multiple reaction monitoring. The analysis time was 18 min per run, with all analytes and internal standards eluting within 8 min. The calibration range was 25-4000 ng/mL for imatinib, 5-800 ng/mL for N-desmethyl imatinib (CGP74588), and 2.5-400 ng/mL for sunitinib and N-desethyl sunitinib (SU12662). Intra- and inter-assay precision were both below 15%, and accuracy ranged between 90.0% and 101.9%. The method was successfully applied to determine blood samples from 120 patients with gastrointestinal stromal tumors who received imatinib (n = 115) and sunitinib (n = 5). It has been validated as linear, accurate, precise, and robust, making it suitable for therapeutic drug monitoring of imatinib and sunitinib in routine clinical practice.

KIT/PDGFRA inhibitors for the treatment of gastrointestinal stromal tumors: getting to the gist of the problem

INTRODUCTION

Approximately 90% of gastrointestinal stromal tumors (GISTs) are driven by activating mutations in receptor tyrosine-kinases KIT or PDGFRA. Despite the outstanding results of first-line imatinib in advanced GIST, resistance ultimately occurs mainly through secondary mutations in KIT/PDGFRA. Other tyrosine-kinase inhibitors (TKIs) with a broader spectrum of activity against these mutations are approved after imatinib failure. However, response rates and progression-free survival are drastically lower compared to imatinib. Notably, imatinib also triggers early tolerance adaptation mechanisms, which precede the occurrence of secondary mutations.

AREAS COVERED

In this review, we outline the current landscape of KIT inhibitors, discuss the novel agents, and present additional biological pathways that may be therapeutically exploitable.

EXPERT OPINION

The development of broad-spectrum and highly selective TKIs able to induce a sustained KIT/PDGFRA inhibition is the pillar of preclinical and clinical investigation in GIST. However, it is now recognized that the situation is more intricate, with various factors interacting with KIT and PDGFRA, playing a crucial role in the response and resistance to treatments. Future strategies in the management of advanced GIST should integrate driver inhibition with the blockade of other molecules to enhance cell death and establish enduring responses in patients.

Therapeutic drug monitoring of imatinib - how far are we in the leukemia setting?

INTRODUCTION

Tyrosine kinase inhibitors (TKIs) have revolutionized survival rates of chronic myeloid leukemia (CML) and Philadelphia chromosome positive (Ph+) acute lymphoblastic leukemia (ALL) and replaced hematopoietic stem cell transplantation (hSCT) as the key treatment option for these patients. More recently, the so-called Philadelphia chromosome-like (Ph-like) ALL has similarly benefitted from TKIs. However, many patients shift from the first generation TKI, imatinib, due to treatment-related toxicities or lack of treatment efficacy. A more personalized approach to TKI treatment could counteract these challenges and potentially be more cost-effective. Therapeutic drug monitoring (TDM) has led to higher response rates and less treatment-related toxicity in adult CML but is rarely used in ALL or in childhood CML.

AREAS COVERED

This review summarizes different antileukemic treatment indications for TKIs with focus on imatinib and its pharmacokinetic/-dynamic properties as well as opportunities and pitfalls of TDM for imatinib treatment in relation to pharmacogenetics and co-medication for pediatric and adult Ph+/Ph-like leukemias.

EXPERT OPINION

TDM of imatinib adds value to standard monitoring of ABL-class leukemia by uncovering non-adherence and potentially mitigating adverse effects. Clinically implementable pharmacokinetic/-dynamic models adjusted for relevant pharmacogenetics could improve individual dosing. Prospective trials of TDM-based treatments, including both children and adults, are needed.

Dermatofibrosarcoma protuberans: Case series in a tropical setting and review of literature

Dermatofibrosarcoma protuberans (DFSP) is an infrequent cutaneous tumour that may involve subcutaneous fat and in some cases fascia, muscles and bone. The infrequent occurrence lessens its clinical awareness in addition to its clinical semblance to many common cutaneous lesions. It is characterized by proclivity for local recurrence. We evaluated the clinical presentation and treatment outcomes of six consecutive cases of DFSP with histologic diagnosis in the University of Calabar Teaching Hospital, Calabar seen between January 2013 and December 2022. This was compared with total cutaneous malignances in the same period. The six consecutive patients comprised of two males and four females (M = F: 1:2) whose ages ranged from 21 to 57 years (mean of 36.5 years) and accounted for 7% of cutaneous malignancies. The site distribution was trunk (back) involved in 3 (50%) of the patients, limbs 3 (50%); upper 1 (17%) and lower limb 2 (33%). Clinical presentation was in the form of firm cutaneous mass with some ulcerated lesions that bled and some fungated. 50 percent of the patients presented with recurrent lesions and in all there was no regional lymphadenopathy or evidence of metastasis. There was a patient with Neurofibromatosis- 1 who had a huge fungated limb lesion offered amputation, four had wide local excision and one incision biopsy. Follow up was poor and the period ranged from 2 to 14 months (mean 7 months). Dermatofibrosarcoma protuberans is an uncommon tumour with clinical semblance to other cutaneous lesions. Early presentation, preoperative histologic diagnosis will enhance the goal of ensuring adequate excision. Adjuvant therapy with Imatinib with or without adjuvant radiotherapy are recommended in the treatment plan in view of the frequency of late presentation with advanced recurrent lesions and poor follow up.

HIF2-α Expression in CML Patients Receiving Hydroxyurea Prior to Imatinib That Achieved Major Molecular Response (MMR) versus in Those Not Achieving MMR

Introduction

Currently, Imatinib (IM) which is a Tyrosine Kinase Inhibitor (TKI), is the main treatment for patients with chronic myeloid leukemia (CML). Major molecular response (MMR) is used as therapeutic response. Resistance to IM may be caused by hypoxia which is regulated by hypoxia inducible factor (HIF) 2-α. The role of HIF2-α is currently not researched extensively. This study aimed to analyse the differences in HIF-2α expression between chronic phase CML patients that achieved MMR and those that did not achieve MMR.

Methods

This study used a cross-sectional method which analysed secondary data from whole blood samples in chronic phase CML patients aged 18-60 years that received hydroxyurea (HU) before IM, aged 18-60 years, received IM therapy for more than 12 months, and were willing to participate in the study. The exclusion criteria for this study were patients who were receiving IM at a dose of more than 400 mg/day. HIF-2α protein expression was examined using the enzyme-linked immunosorbent assay (ELISA) method. Differences between HIF-2α protein expression in groups that achieved MMR versus not achieving MMR was analysed using the Mann-Whitney test.

Results

A total of 79 subjects were obtained. The median HIF-2α was 90.56 pg/mg protein (3.01-4628.74). There was no statistically significant difference in expression of HIF-2α in the group that reached MMR and did not reach MMR, namely 123.45 pg/mg protein and 89.25 pg/mg protein respectively (p 0.718).

Conclusion

This study found no statistically significant difference between HIF-2α expression level and MMR achievement of chronic phase CML patients who received HU before IM therapy.

Unexpected reaction of "wild-type" gastrointestinal stromal tumor to imatinib: case report and literature review

Background

Most of gastrointestinal stromal tumors (GISTs) are driven by mutations in the KIT/PDGFRA genes and can benefit from TKIs treatment. However, a small subset of GIST (10%-15%) are called "wild-type" GISTs due to the lack of these mutations. Theoretically, they would not benefit from TKIs treatment and may even develop resistance. Therefore, this unexpected response may challenge inherent perceptions. Herein, we present a case of giant wild-type GIST exhibiting an unexpected response to imatinib(IM), followed by laparoscopic surgical resection. Subsequently, potential underlying mechanisms are discussed.

Case description

This case describes a 57-year-old man who presented with abdominal pain for two weeks. CT revealed a massive lesion near the splenic hilum along the greater curvature of the stomach, concurrently involving the splenic hilar vessels and surrounding lymph nodes. Ultrasound-guided fine needle aspiration biopsy confirmed it is a mesenchymal spindle cell tumor,GIST. Due to the enormous volume and local invasion, neoadjuvant chemotherapy was initially considered. After 6 months of IM 400 mg/d, CT imaging revealed marked changes in tumor heterogeneity and a significant reduction in volume. Subsequently, laparoscopic surgical resection was performed. Postoperative pathological examination, immunohistochemistry, and genetic testing collectively confirmed it is a wild-type GIST.The patient recovered well and was discharged on the 6th day after surgery, with continued oral IM(400 mg/d) after discharge. No recurrence was observed during follow-up until the publication of this report.

Conclusion

This unexpected response suggests that wild-type GISTs may benefit from TKIs treatment, and the potential mechanisms warrant further investigation. Additionally, true wild-type GIST may not be discerned due to current limitations of Next-Generation Sequencing(NGS). Therefore, for advanced/high-risk GIST, additional genetic analysis can be performed after negative NGS results.

Chronic myeloid leukemia with two rare fusion gene transcripts of atypical BCR::ABL: A case report and literature review

RATIONALE

Imatinib is a standard treatment for Philadelphia (Ph) chromosome-positive chronic myeloid leukemia (CML), but its efficacy in rare BCR::ABL variants is underexplored.

PATIENT CONCERNS

A 67-year-old woman was admitted to the Second Affiliated Hospital of Xi'an Jiaotong University in March 2022 due to elevated white blood cells.

DIAGNOSIS

Karyotype analysis revealed clonal abnormalities involving the variant t(9;22) and positive results for atypical BCR::ABL variants (e14a3 and e13a3). The clinical diagnosis was CML, chronic phase, Ph+, with rare BCR::ABL-e13a3- and BCR::ABL-e14a3-positive findings.

INTERVENTION

The patient was administered daily imatinib mesylate (400 mg).

OUTCOMES

After 4 weeks, a swift molecular response was observed: BCR::ABL-e13a3 transcript level at 2.82 × 10-1 (28.24%), and BCR::ABL-e14a3 transcript level at 4.68 × 10-1 (46.76%). Within 3 months, a complete cytogenetic response was achieved, with a Ph chromosome ratio of 0. Early molecular response was evident as BCR::ABL-e13a3 transcript level reached 5.11 × 10-3 (0.51%), and BCR::ABL-e14a3 transcript level at 6.26 × 10-3 (0.63%). The imatinib mesylate treatment continued without significant toxicity.

LESSONS

This case emphasizes the potential effectiveness of imatinib mesylate in managing rare BCR::ABL fusion gene variants of CML. Screening for these atypical variants is advised for suspected CML patients who test negative for common BCR::ABL fusion gene variants. The presented case underscores the positive outcomes achieved with imatinib treatment for a patient with rare BCR::ABL variants, contributing valuable insights for the management of similar cases. Screening for unusual fusion gene variants should be a consideration in CML diagnosis for comprehensive treatment strategies.

GDF15 Protects Insulin-Producing Beta Cells against Pro-Inflammatory Cytokines and Metabolic Stress via Increased Deamination of Intracellular Adenosine

It has been proposed that antidiabetic drugs, such as metformin and imatinib, at least in part, promote improved glucose tolerance in type 2 diabetic patients via increased production of the inflammatory cytokine GDF15. This is supported by studies, performed in rodent cell lines and mouse models, in which the addition or production of GDF15 improved beta-cell function and survival. The aim of the present study was to determine whether human beta cells produce GDF15 in response to antidiabetic drugs and, if so, to further elucidate the mechanisms by which GDF15 modulates the function and survival of such cells. The effects and expression of GDF15 were analyzed in human insulin-producing EndoC-betaH1 cells and human islets. We observed that alpha and beta cells exhibit considerable heterogeneity in GDF15 immuno-positivity. The predominant form of GDF15 present in islet and EndoC-betaH1 cells was pro-GDF15. Imatinib, but not metformin, increased pro-GDF15 levels in EndoC-betaH1 cells. Under basal conditions, exogenous GDF15 increased human islet oxygen consumption rates. In EndoC-betaH1 cells and human islets, exogenous GDF15 partially ameliorated cytokine- or palmitate + high-glucose-induced loss of function and viability. GDF15-induced cell survival was paralleled by increased inosine levels, suggesting a more efficient disposal of intracellular adenosine. Knockdown of adenosine deaminase, the enzyme that converts adenosine to inosine, resulted in lowered inosine levels and loss of protection against cytokine- or palmitate + high-glucose-induced cell death. It is concluded that imatinib-induced GDF15 production may protect human beta cells partially against inflammatory and metabolic stress. Furthermore, it is possible that the GDF15-mediated activation of adenosine deaminase and the increased disposal of intracellular adenosine participate in protection against beta-cell death.

Tyrosine Kinase Inhibition Activates Intratumoral γδ T Cells in Gastrointestinal Stromal Tumor

γδ T cells are a rare but potent subset of T cells with pleiotropic functions. They commonly reside within tumors but the response of γδ T cells to tyrosine kinase inhibition is unknown. To address this, we studied a genetically engineered mouse model of gastrointestinal stromal tumor (GIST) driven by oncogenic Kit signaling that responds to the Kit inhibitor imatinib. At baseline, γδ T cells were antitumoral, as blockade of either γδ T-cell receptor or IL17A increased tumor weight and decreased antitumor immunity. However, imatinib therapy further stimulated intratumoral γδ T cells, as determined by flow cytometry and single-cell RNA sequencing (scRNA-seq). Imatinib expanded a highly activated γδ T-cell subset with increased IL17A production and higher expression of immune checkpoints and cytolytic effector molecules. Consistent with the mouse model, γδ T cells produced IL17A in fresh human GIST specimens, and imatinib treatment increased γδ T-cell gene signatures, as measured by bulk tumor RNA-seq. Furthermore, tumor γδ T cells correlated with survival in patients with GIST. Our findings highlight the interplay between tumor cell oncogene signaling and antitumor immune responses and identify γδ T cells as targets for immunotherapy in GIST.

Imatinib inhibits oral squamous cell carcinoma by suppressing the PI3K/AKT/mTOR signaling pathway

Oral squamous cell carcinoma (OSCC) is a prevalent oral and maxillofacial cancer with high mortality as OSCC cells readily invade tissues and metastasize to cervical lymph nodes. Although imatinib exhibits potential anticancer and remarkable clinical activities that therapeutically affect several cancer types, its specific impact on OSCC has yet to be fully explored. Therefore, this study investigated the potential anticancer effect of imatinib on OSCC cells and the underlying mechanisms. The Cell Counting Kit-8 was used to determine the impact of imatinib on cell viability. Then, morphological cell proliferation analysis was conducted to examine how imatinib impacted OSCC cell growth. Moreover, OSCC cell migration was determined through wound-healing assays, and colony formation abilities were investigated through the soft agar assay. Lastly, the effect of imatinib on OSCC cell apoptosis was verified with flow cytometry, and its inhibitory mechanism was confirmed through Western blot. Our results demonstrate that imatinib effectively inhibited OSCC cell proliferation and significantly curtailed OSCC cell viability in a time- and concentration-dependent manner. Furthermore, imatinib suppressed migration and colony formation while promoting OSCC cell apoptosis by enhancing p53, Bax, and PARP expression levels and reducing Bcl-2 expression. Imatinib also inhibited the PI3K/AKT/mTOR signaling pathway and induced OSCC cell apoptosis, demonstrating the potential of imatinib as a treatment for oral cancer.

DDR1/2 enhance KIT activation and imatinib resistance of primary and secondary KIT mutants in gastrointestinal stromal tumors

Gastrointestinal stromal tumors (GISTs) are predominantly initiated by KIT mutations. In this study, we observed that discoidin domain receptors 1 and 2 (DDR1 and DDR2) exhibited high expression in GISTs, were associated with KIT, and enhanced the activation of both wild-type KIT and primary KIT mutants. Inhibition of DDR1/2 led to a reduction in the activation of KIT and its downstream signaling molecules, ultimately impairing GIST cell survival and proliferation in vitro. Consequently, treatment of mice carrying germline KIT/V558A mutation with DDR1/2 inhibitor significantly impeded tumor growth, and the combined use of DDR1/2 inhibitor and imatinib, the first-line targeted therapeutic agent for GISTs, markedly enhanced tumor growth suppression. In addition, DDR1/2 inhibition resulted in decreased KIT expression, while KIT inhibition led to upregulation of DDR1/2 expression in GISTs. The presence of DDR1/2 also decreased the sensitivity of wild-type KIT or primary KIT mutants to imatinib, indicating a possible role for DDR1/2 in promoting GIST survival during KIT-targeted therapy. The development of drug-resistant secondary KIT mutations is a primary factor contributing to GIST recurrence following targeted therapy. Similar to primary KIT mutants, DDR1/2 can associate with and enhance the activation of secondary KIT mutants, further diminishing their sensitivity to imatinib. In summary, our data demonstrate that DDR1/2 contribute to KIT activation in GISTs and strengthen resistance to imatinib for both primary and secondary KIT mutants, providing a rationale for further exploration of DDR1/2 targeting in GIST treatment.

Efficient treatment of colon cancer with codelivery of TRAIL and imatinib by liposomes

To solve the problem of resistance of tumor cells to TRAIL and the inevitable side effects of imatinib during treatment, we successfully prepared a kind of multifunctional liposome that encapsulated imatinib in its internal water phase and inserted TRAIL on its membrane in this study, which named ITLPs. The liposomes appeared uniform spherical and the particle size was approximately 150 nm. ITLPs showed high accumulation in TRAIL-resistance cells and HT-29 tumor-bearing mice model. In vitro cytotoxicity assay results showed that the killing activity of HT-29 cells treated with ITLPs increased by 50% and confirmed that this killing activity was mediated by the apoptosis pathway. Through mechanism studies, it was found that ITLPs arrested up to 32.3% of cells in phase M to exert anti-tumor effects. In vivo anti-tumor study showed that ITLPs achieved 61.8% tumor suppression and little toxicity in the HT-29 tumor-bearing mice model. Overall results demonstrated that codelivery of imatinib and TRAIL via liposomes may be a prospective method in the treatment of the TRAIL-resistance tumor.

BMPR2 mutation and clinical response to imatinib in a case of heritable pulmonary arterial hypertension

Bone morphogenetic protein receptor 2 (BMPR2) mutation is the most common gene mutation implicated in the pathogenesis of pulmonary arterial hypertension (PAH). We describe, for the first time, an excellent clinical response to tyrosine kinase inhibitor imatinib in a patient with heritable PAH from BMPR2 mutation.

Gastric gastrointestinal stromal tumors: therapeutic strategies and long-term prognosis

OBJECTIVES

This study aimed to evaluate the clinical and prognostic characteristics of primary gastric gastrointestinal stromal tumors (GIST).

METHODS

Patients who underwent resection for primary gastric GIST between January 2002 and December 2017 were included. Recurrence-free survival (RFS) was calculated by Kaplan-Meier analysis, and Cox proportional hazards model was used to identify independent prognostic factors.

RESULTS

Altogether, 653 patients were enrolled. The median patient age was 59 years (range 15-86 years). Open, laparoscopic, and endoscopic resections were performed in 394 (60.3%), 105 (16.1%), and 154 (23.6%) patients, respectively. According to the modified NIH consensus classification, 132 (20.2%), 245 (37.5%), 166 (25.4%), and 88 (13.5%) patients were categorized into very low-, low-, intermediate-, and high-risk, respectively. A total of 136 (20.8%) patients received adjuvant imatinib treatment. The median follow-up time was 78 months (range 4-219 months), and the estimated 5-year RFS rate was 93.0%. In all patients, tumor size and rupture, mitotic counts, and adjuvant imatinib treatment were independent prognostic factors. The prognosis of gastric GIST treated with endoscopic resection was not significantly different from that of laparoscopic or open resection after adjusting for covariates using propensity score matching (log-rank p = .558). Adjuvant imatinib treatment (HR = 0.151, 95%CI 0.055-0.417, p < .001) was a favorable prognostic factor for high-risk patients, but was not associated with prognosis in intermediate-risk patients.

CONCLUSION

Patients with small gastric GISTs who successfully underwent endoscopic resection may have a favorable prognosis. Adjuvant imatinib treatment improve the prognosis of high-risk gastric GISTs, however, its use in intermediate-risk patients remains controversial.

Uncommon Haematological Transformation: Chronic Myeloid Leukaemia Transitioning Into Plasma Cell Leukaemia in a Single Patient

A 40-year-old male patient who was a known case of chronic myeloid leukaemia (CML) was diagnosed two years back on tab imatinib 400 mg/day; he came with complaints of easy fatigability, syncopal attacks, and bone pain associated with low-grade fever for 15 days. Repeat haematological profile and a peripheral smear of the patient suggested features of plasma cell leukaemia (PCL)/plasma cell dyscrasia (PCD). A definitive treatment protocol of lenalidomide, bortezomib, and dexamethasone for PCL was prescribed to the patient. This medical case study emphasizes the rare possibility of the transformation of CML into PCL and the possible trigger of tyrosine kinase inhibitor for the same.

Identification of common genes and pathways underlying imatinib and nilotinib treatment in CML: a Bioinformatics Study

Imatinib (IMA) and nilotinib are the first and second generations of BCR-ABL tyrosine kinase inhibitors, which widely applied in chronic myeloid leukemia (CML) treatment. Here we aimed to provide new targets for CML treatment by transcriptome analysis. Microarray data GSE19567 was downloaded and analyzed from Gene Expression Omnibus (GEO) to identify common genes, which are downregulated or upregulated in K562-imatinib and K562-nilotinib treated cells. The differentially expressed genes (DEGs) were assessed, and STRING and Cytoscape were used to create the protein-protein interaction (PPI) network. In imatinib and nilotinib treated groups' comparison, there were common 626 upregulated and 268 downregulated genes, which were differentially expressed. The GO analysis represented the enrichment of DEGs in iron ion binding, protein tyrosine kinase activity, transcription factor activity, ATP binding, sequence-specific DNA binding, cytokine activity, the mitochondrion, sequence-specific DNA binding, plasma membrane and cell-cell adherens junction. KEGG pathway analysis revealed that downregulated DEGs were associated with pathways including microRNAs in cancer and PI3K-Akt signaling pathway. Furthermore, upregulated DEGs were involved in hematopoietic cell lineage, lysosome and chemical carcinogenesis. Among the upregulated genes, MYH9, MYH14, MYL10, MYL7, MYL5, RXRA, CYP1A1, FECH, AKR1C3, ALAD, CAT, CITED2, CPT1A, CYP3A5, CYP3A7, FABP1, HBD, HMBS and PPOX genes were found as hub genes. Moreover, 20 downregulated genes, YARS, AARS, SARS, GARS, CARS, IARS, RRP79, CEBPB, RRP12, UTP14A, PNO1, CCND1, DDX10, MYC, WDR43, CEBPG, DDIT3, VEGFA, PIM1 and TRIB3 were identified as hub genes. These genes have the potential to become target genes for diagnosis and therapy of CML patients.

Metabolic pseudoprogression in a patient with metastatic KIT exon 11 GIST after 1 month of first-line imatinib: a case report

Background

Positron emission tomography (PET) with 18-fluorodeoxyglucose (18FDG) has proven to be highly sensitive in the early assessment of tumor response in gastrointestinal stromal tumors (GIST), especially in cases where there is doubt or when the early prediction of the response could be clinically useful for patient management. As widely known, kinase mutations have an undoubtful predictive value for sensitivity to imatinib, and the inclusion of KIT and PDGFRa mutational analysis in the diagnostic workup of all GIST is now considered standard practice.

Case presentation

Herein, we described in detail a case of an exon 11 KIT mutated-metastatic GIST patient, who presented an unexpected metabolic progression at the early 18FDG-PET evaluation after 1 month of first-line imatinib, unconfirmed at the liver biopsy performed near after, which has conversely shown a complete pathological response.

Conclusions

This report aims to highlight the existence of this metabolic pseudoprogression in GIST at the beginning of imatinib therapy in order to avoid early treatment discontinuation. Therefore, an early metabolic progression during a molecular targeted therapy always deserves to be evaluated in the context of the disease molecular profiling, and in case of a discordant finding between functional imaging and molecular background, a short-term longitudinal control should be suggested.

Keratosis Pilaris-like Eruption during Treatment of Chronic Myeloid Leukemia with Tyrosine Kinase Inhibitors: Literature Review and Report of a Case Related to Imatinib

The advent of tyrosine kinase inhibitors (TKIs) blocking BCR-ABL activity has revolutionized the therapeutic management of patients with chronic myeloid leukemia (CML). Adverse cutaneous reactions (ACRs) are common nonhematologic adverse events associated with the use of BCR-ABL TKIs. A characteristic pattern of eruption resembling keratosis pilaris (KP) has been described in patients treated with these drugs, especially nilotinib and dasatinib. The pathogenesis of this ACR is still unknown. This type of reaction appears to be uncommon with imatinib. Here, we report the case of an elderly patient with an asymptomatic KP-like eruption, which appeared one month after starting treatment with imatinib for CML. The case presentation is accompanied by a review of similar reactions in patients with CML treated with BCR-ABL inhibitors, attempting to make an excursus on the molecular targets of such drugs and possible mechanisms underlying this ACR.

Establishment of the Myeloid TBX-Code Reveals Aberrant Expression of T-Box Gene TBX1 in Chronic Myeloid Leukemia

T-box genes encode transcription factors, which control developmental processes and promote cancer if deregulated. Recently, we described the lymphoid TBX-code, which collates T-box gene activities in normal lymphopoiesis, enabling identification of members deregulated in lymphoid malignancies. Here, we have extended this analysis to cover myelopoiesis, compiling the myeloid TBX-code and, thus, highlighting which of these genes might be deregulated in myeloid tumor types. We analyzed public T-box gene expression datasets bioinformatically for normal and malignant cells. Candidate T-box-gene-expressing model cell lines were identified and examined by RQ-PCR, Western Blotting, genomic profiling, and siRNA-mediated knockdown combined with RNA-seq analysis and live-cell imaging. The established myeloid TBX-code comprised 10 T-box genes, including progenitor-cell-restricted TBX1. Accordingly, we detected aberrant expression of TBX1 in 10% of stem/progenitor-cell-derived chronic myeloid leukemia (CML) patients. The classic CML cell line K-562 expressed TBX1 at high levels and served as a model to identify TBX1 activators, including transcription factor GATA1 and genomic amplification of the TBX1 locus at 22q11; inhibitors, including BCR::ABL1 fusion and downregulated GNAI2, as well as BMP, FGF2, and WNT signaling; and the target genes CDKN1A, MIR17HG, NAV1, and TMEM38A. The establishment of the myeloid TBX-code permitted identification of aberrant TBX1 expression in subsets of CML patients and cell lines. TBX1 forms an integral part of an oncogenic regulatory network impacting proliferation, survival, and differentiation. Thus, the data spotlight novel diagnostic markers and potential therapeutic targets for this malignancy.

Therapeutic drug monitoring and pharmacogenetics to tune imatinib exposure in gastrointestinal stromal tumor patients: hurdles and perspectives for clinical implementation

Tweetable abstract Present evidence supports the use of intensified pharmacologic monitoring of #imatinib including #TherapeuticDrugMonitoring and #PGx to improve outcomes in patients with GI stromal tumor. Future studies need to address emerging questions to facilitate implementation in clinics.

Effect of Imatinib treatment on renal anaemia in chronic myeloid leukemia patients

PURPOSE

In this study, we investigate renal function and anaemia during imatinib treatment in patients with chronic myeloid leukaemia.

METHODS

The patients with chronic myeloid leukaemia with chronic phase who had been treated with only imatinib for 12 months at Rajiv Gandhi Cancer Institute and Research Centre (New Delhi, India) were enrolled and prospectively analysed. The chronic renal impairment parameters, including estimated glomerular filtration rate and haemoglobin levels for anaemia from June 2020 to June 2022, were monitored in newly diagnosed in patients with chronic myeloid leukaemia-chronic phase. The data were analysed by SPSS software version 22.

RESULTS

In total 55 patients with chronic myeloid leukaemia chronic phase who had been on imatinib for 12 months were monitored. The mean estimated glomerular filtration rate was significantly decreased (74 ± 14 to 59 ± 12 mL/min/1.73m2, p < 0.001) with a decrease in mean haemoglobin levels after 12 months (10.9 ± 2.01 to 9.0 ± 1.02, p < 0.004). The decreased estimated glomerular filtration rate was negatively correlated with haemoglobin levels after 1 year of imatinib administration (correlation coefficient = 0.892, R2 = 0.7976, p < 0.05).

CONCLUSION

We recommended close monitoring of renal function and haemoglobin levels in patients with chronic myeloid leukaemia patients.

Validation of imatinib therapy failure score (IMTF) in chronic phase chronic myeloid leukemia in real life practice

The outcome of chronic myeloid leukemia (CML) patients improved in the last decade. Clinical prognostic scoring systems aim to provide information about survival in the long-term, without determining from baseline the subset of patients who require a strictly monitoring because at increased risk of failure. Imatinib, the first-generation tyrosine kinase inhibitor (TKI), is still widely used as frontline treatment: recently, the imatinib therapy failure (IMTF) score was proposed to identify the failure free survival. Aim of our study was to validate this index in a large cohort of patients treated with imatinib.

Some 2-[4-(1H-benzimidazol-1-yl) phenyl]-1H-benzimidazole derivatives overcome imatinib resistance by induction of apoptosis and reduction of P-glycoprotein activity

Imatinib (IMA) is a tyrosine kinase inhibitor (TKI) introduced for the chronic myeloid leukemia (CML) therapy. Emergence of IMA resistance leads to the relapse and failure in CML therapy. Benzimidazole is a heterocyclic organic compound which is widely investigated for the development of anticancer drugs. In this study, we aimed to explore the anticancer effects of some 2-[4-(1H-benzimidazol-1-yl) phenyl]-1H-benzimidazole derivatives on K562S (IMA-sensitive) and K562R (IMA-resistant) cells. To analyze the cytotoxic and apoptotic effects of the compounds, K562S, K562R, and L929 cells were exposed to increasing concentrations of the derivatives. Cytotoxic effects of compounds on cell viability were analyzed with MTT assay. Apoptosis induction, caspase3/7 activity were investigated with flow cytometry and BAX, BIM, and BAD genes expression levels were analyzed with qRT-PCR. Rhodamine123 (Rho-123) staining assays were carried out to evaluate the effect of compounds on P-glycoprotein (P-gp) activity. The hit compounds were screened using molecular docking, and the binding preference of each compounds to BCR-ABL protein was evaluated. Our results indicated that compounds triggered cytotoxicity, caspase3/7 activation in K562S and K562R cells. Rho-123 staining showed that compounds inhibited P-gp activity in K562R cells. Overall, our results reveal some benzimidazole derivatives as potential anticancer agents to overcome IMA resistance in CML.

Therapeutic Drug Monitoring of Imatinib and N-Desmethyl Imatinib in Chronic Myeloid Leukemia Patients Using LC-MS/MS in a Cohort Study

Imatinib is an oral tyrosine kinase inhibitor (TKI) and first-line therapy for patients with chronic myeloid leukemia (CML). There is a positive correlation between serum imatinib concentrations and treatment response. However, the specific relationship between the blood concentration of imatinib and its influencing factors remains unclear. This study collected basic information from 102 patients using imatinib as first-line treatment for CML. Further, we analyzed the individual differences in imatinib concentration and explored its influencing factors. Through intra-day and inter-day precision studies, we found that the precision for the imatinib assay methodology was within ±13% and that the recovery rate was above 85%. There is notable individual variation in the blood concentration of imatinib; the recommended treatment concentration is 860-1500 ng/mL, with only 41.40% of patients achieving this concentration. Also, there was a negative correlation between age and imatinib trough concentration (Ctrough ), as is observed between age and N-desmethyl imatinib. Moreover, compared with the adolescent group, the serum imatinib Ctrough for groups aged 17-47 and 48-68 years was significantly reduced. Further analysis shows that imatinib Ctrough values reaching therapeutic concentrations (59%) increased dramatically for patients with CML aged 17-47 years. Moreover, groups dosed with 400 mg/day resulted in therapeutic imatinib concentrations for 68% of patients with CML, which was the best performance. The established method was validated, with acceptable accuracy, precision, linearity, and stability, as required, and then successfully applied to the therapeutic drug monitoring of imatinib. Age, dose, and metabolites can influence the imatinib concentration and its therapeutic effect in patients with CML.

Canine oral melanoma with suspected pulmonary metastasis: Combination of immunotherapy and tyrosine kinase inhibitor treatment

This case report follows a 10-year-old castrated male Miniature Schnauzer dog presented with a history of incomplete surgical resection of an oral malignant melanoma (amelanotic type) on the right mandible. Melanoma vaccine therapy was administered due to incomplete surgical resection, however, new masses were detected on the contralateral mandible and suspected pulmonary metastasis occurred at 2 weeks and 7 months, respectively, following the first melanoma vaccination. At the time of detecting the pulmonary metastasis, targeted chemotherapy was initiated with the owner's consent using imatinib (10 mg/kg/day, p.o.), a tyrosine kinase inhibitor (TKI). The patient did not show any significant adverse events related to both anticancer treatments. Three months following the first dose of imatinib, the absence of the suspected pulmonary metastatic nodules on radiography indicated complete remission. In conclusion, this report describes the achievement of clinical remission of suspected pulmonary metastatic oral malignant melanoma and an extension of survival time in a dog given a combination treatment of immunotherapy and tyrosine kinase inhibitor.

Cytoreductive surgery in patients with recurrent or metastatic gastrointestinal stromal tumors sensitive to imatinib: a retrospective analysis of two Russian cancer centers

Background

The role of cytoreductive surgery for patients with recurrent or metastatic gastrointestinal stromal tumors (mGISTs) responding to imatinib (IM) has not yet been established. We carried out a retrospective analysis of the outcomes of patients with mGISTs in two Russian cancer centers. We compared two cohorts: treated (Group S) or not treated with surgery (Group NS) after a partial response (PR) or stable disease (SD) while on IM.

Methods

A total 44 patients treated by IM as first line treatment were included in our analysis. Prognostically similar patients only sensitive to IM cases with hepatic or peritoneal metastases as well as durable response to IM lasting more than 12 months were included in a control arm. Patients in Group NS received only IM until disease progression. Patients in Group S were treated additionally with metastasectomy after having response or SD on IM.

Results

The baseline characteristics were similar between the groups with several trends: a higher proportion of patients achieved a PR in Group S (87% vs. 55%, P=0.165), and greater number of patients had peritoneal metastases in Group NS (45% vs. 27%, P=0.759). The median time to surgery from the initiation of IM was 8 months. Progression-free survival (PFS) and overall survival (OS) were significantly longer in Group S than Group NS: the median PFS was 78 vs. 35 months (P=0.088); the median OS was 141 vs. 80 months (P=0.154).

Conclusions

The surgical resection of residual lesions after disease control with IM is likely to be beneficial to patients with mGISTs.

Low-Intensity and Chemo-Free Treatments in Ph+ ALL: Progression-Free Survival Based on Indirect Comparisons

In Philadelphia chromosome-positive B-cell (Ph+) acute lymphoblastic leukemia (LLA), growing evidence has accumulated regarding the efficacy of low-intensity and chemo-free regimens. Our objective was to analyze all recent trials evaluating these treatments and to compare them in terms of efficacy. We applied the Shiny method, an artificial intelligence technique, to analyze Kaplan-Meier curves and reconstruct patient-level data. Reconstructed patient data were then evaluated through standard survival statistics and subjected to indirect head-to-head treatment comparisons. The endpoint was progression-free survival (PFS). Based on 432 reconstructed patients, eight trials were analyzed. The survival data from these trials were pooled into three types of treatments: (i) treatments based on tyrosine kinase inhibitors (TKIs) combined with reduced-intensity chemotherapy (denoted as TKICHE); (ii) TKIs associated with steroids with no chemotherapy (TKISTE); (iii) chemotherapy-free combinations of blinatumomab plus TKIs (TKIBLI). According to the Shiny method, the three PFS curves were reported in a single Kaplan-Meier graph and subjected to survival statistics. In terms of PFS, TKIBLI ranked first, TKICHE second, and TKISTE third; the differences between these three regimens were statistically significant. This multi-treatment Kaplan-Meier graph, generated through the Shiny method, summarized the current evidence on these treatments in both qualitative and quantitative terms.

Stem Cell Responsiveness to Imatinib in Chronic Myeloid Leukemia

Chronic myeloid leukemia (CML) is a clonal myeloproliferative disease characterized by the presence of the BCR-ABL fusion gene, which results from the Philadelphia chromosome. Since the introduction of tyrosine kinase inhibitors (TKI) such as imatinib mesylate (IM), the clinical outcomes for patients with CML have improved significantly. However, IM resistance remains the major clinical challenge for many patients, underlining the need to develop new drugs for the treatment of CML. The basis of CML cell resistance to this drug is unclear, but the appearance of additional genetic alterations in leukemic stem cells (LSCs) is the most common cause of patient relapse. However, several groups have identified a rare subpopulation of CD34+ stem cells in adult patients that is present mainly in the bone marrow and is more immature and pluripotent; these cells are also known as very small embryonic-like stem cells (VSELs). The uncontrolled proliferation and a compromised differentiation possibly initiate their transformation to leukemic VSELs (LVSELs). Their nature and possible involvement in carcinogenesis suggest that they cannot be completely eradicated with IM treatment. In this study, we demonstrated that cells from CML patients with the VSELs phenotype (LVSELs) similarly harbor the fusion protein BCR-ABL and are less sensitive to apoptosis than leukemic HSCs after IM treatment. Thus, IM induces apoptosis and reduces the proliferation and mRNA expression of Ki67 more efficiently in LHSCs than in leukemic LVSELs. Finally, we found that the expression levels of some miRNAs are affected in LVSELs. In addition to the tumor suppressor miR-451, both miR-126 and miR-21, known to be responsible for LSC leukemia-initiating capacity, quiescence, and growth, appear to be involved in IM insensitivity of LVSELs CML cell population. Targeting IM-resistant CML leukemic stem cells by acting via the miRNA pathways may represent a promising therapeutic option.

Temporal effect of imatinib adherence on time to remission in chronic myeloid leukemia patients

INTRODUCTION

Adherence to imatinib in chronic myeloid leukemia (CML) patients is estimated to be as low as 70% despite its clinical benefit, and our understanding of the impact of nonadherence in this population is limited. This study presents a novel application of the Alternating Conditional Estimation (ACE) algorithm in newly diagnosed CML patients to map the full dose-response curve (DRC) and determine how the strength of this curve varies over time.

METHODS

We applied the ACE algorithm alongside a backward elimination procedure to detect the presence of time dependence and nonlinearity in the relationship between imatinib adherence and time-to-remission. An extended Cox model allowing for the flexible modeling of identified effects via unpenalized B-splines was subsequently fit and assessed.

RESULTS

The substantial improvement in model fit associated with the extended Cox approach suggests that traditional Cox proportional hazards model assumptions do not hold in this setting. Results indicate that the DRC for imatinib is non-linearly increasing, with an attenuated effect above a 74% adherence rate. The strength of this effect on remission varied over time and was strongest in the initial months of treatment, reaching a peak around 90 days post-initiation (log hazard ratio: 2.12, 95% confidence interval: 1.47 to 2.66).

CONCLUSION

Most patients that achieved remission did so by 4 months (120 days) with consistently high adherence, suggesting that this could be a critical time and duration for realizing treatment benefit and patient monitoring. Findings regarding the relationship between adherence and remission can additionally help guide the design of future studies.

Myeloid/Lymphoid Neoplasms with ETV6::PDGFRB Fusion Gene: A Rare Case of Poor Response to Imatinib and Possible Transformation Mechanisms from Myeloid Neoplasms of Bone Marrow to T-Cell Lymphoblastic Lymphoma Invasion in Lymph Nodes

The ETV6::PDGFRB fusion gene is commonly reported in chronic myelomonocytic leukemia with eosinophilia, yet patients with ETV6::PDGFRB presenting myeloid and lymphoid neoplasms successively have not been reported. Here, we report the first case of a 35-year-old man with myeloid and lymphoid neoplasms harboring an ETV6::PDGFRB fusion gene who demonstrated poor response to imatinib. The patient was diagnosed with an ETV6::PDGFRB fusion gene myeloid neoplasm on initial diagnosis at our hospital. After 5 months of treatment with imatinib, he was diagnosed with T-cell lymphoblastic lymphoma. ETV6::PDGFRB turned negative after increasing the dose of imatinib, but enlarged superficial lymph nodes reappeared the following year. Notably, the patient exhibited a worse response to imatinib treatment. This study describes this rare case and speculates on a possible mechanism.

Gastrointestinal Stromal Tumor: A Clinicopathological Study and Management

Background and aim Gastrointestinal stromal tumors (GISTs) account for a major portion of gastrointestinal mesenchymal tumors. The purpose of the current study is to examine the clinicopathological features, management, and therapeutic outcomes of primary GIST in a tertiary care hospital.  Materials and methods This is a prospective observational analysis. Seventeen patients with GIST have been detected and treated in the Department of Surgery of a tertiary care hospital with an attached medical institution over the last seven years. The clinical presentation, diagnosis method, tumor locations, histopathological results, surgical treatment, and postoperative results were analyzed.  Results There were six females and 11 males with ages ranging between 35 to 72 years. All the patients had symptoms, with abdominal pain the most prevalent. The most frequent primary site for GIST was the stomach (60-70%), followed by the small intestine (25-30%), the rectum, the esophagus, and the colon (2%). Preoperative diagnosis was made through endoscopy and a contrast-enhanced CT scan. Ninety-two percent of the cases tested positive for CD117. Surgery has been conducted for all 17 patients, with the liver being the most common site of metastasis. Imatinib and sunitinib increased the survival as well as postoperative recurrence rate while decreasing metastasis.  Conclusions The most general symptom of GIST was abdominal pain. In most instances, it was treated with surgery as well as adjuvant imatinib and sunitinib, and had a favorable prognosis. With increasing size and mitotic activity, the five-year survival rate falls, and the prognosis worsens.

Overcoming phenotypic switching: targeting protein-protein interactions in cancer

Alternative protein-protein interactions (PPIs) arising from mutations or post-translational modifications (PTMs), termed phenotypic switching (PS), are critical for the transmission of alternative pathogenic signals and are particularly significant in cancer. In recent years, PPIs have emerged as promising targets for rational drug design, primarily because their high specificity facilitates targeting of disease-related signaling pathways. However, obstacles exist at the molecular level that arise from the properties of the interaction interfaces and the propensity of small molecule drugs to interact with more than one cleft surface. The difficulty in identifying small molecules that act as activators or inhibitors to counteract the biological effects of mutations raises issues that have not been encountered before. For example, small molecules can bind tightly but may not act as drugs or bind to multiple sites (interaction promiscuity). Another reason is the absence of significant clefts on protein surfaces; if a pocket is present, it may be too small, or its geometry may prevent binding. PS, which arises from oncogenic (alternative) signaling, causes drug resistance and forms the basis for the systemic robustness of tumors. In this review, the properties of PPI interfaces relevant to the design and development of targeting drugs are examined. In addition, the interactions between three tyrosine kinase inhibitors (TKIs) employed as drugs are discussed. Finally, potential novel targets of one of these drugs were identified in silico.

Methods of Surgical Repair for Iatrogenic Sigmoid Colon Perforation Following Colonoscopy: A Case Report and Literature Review

Iatrogenic colonic perforation is a relatively infrequent yet perilous complication arising from both diagnostic and therapeutic colonoscopies, potentially leading to severe septic complications and increased morbidity or mortality. Given the gravity of potential complications, surgical intervention stands as the principal treatment strategy, with various modalities selected based on clinical discretion. In this context, we present the case of a patient who underwent primary laparoscopic repair following the identification of a sigmoid colon perforation during a routine colonoscopy. Intraoperatively, a Jackson-Pratt drain was placed to facilitate postoperative monitoring and drainage. The patient's hospitalization extended to a total of seven days due to sustained drainage and leukocytosis, highlighting the complexities of managing postoperative complications in such cases. This report underscores the current landscape of published data guiding the surgical management of iatrogenic colonic perforation following colonoscopy and highlights both the existing strengths and gaps within the current body of literature. As colonic perforation remains a critical concern in endoscopic procedures, a comprehensive understanding of optimal surgical interventions is crucial for minimizing patient morbidity and ensuring successful outcomes.

Lymphomatoid papulosis associated with myeloid neoplasm with eosinophilia and FIP1L1::PDGFRA rearrangement: Successful imatinib treatment in two cases

Lymphomatoid papulosis (LyP) is a benign condition, listed among primary cutaneous CD30+ lymphoproliferative disorders. Its typical picture consists of relapsing-remitting papular lesions and it can be encountered in the course of a hematologic disease, at times representing its first manifestation. Hypereosinophilic syndromes are a heterogeneous group of disorders characterized by persistent peripheral blood hypereosinophilia that may lead to life-threatening organ damage. Among eosinophilic disorders, the subtype identified as myeloid/lymphoid neoplasm with eosinophilia and tyrosine kinase gene fusions has aroused particular interest due to its excellent response to tyrosine kinase inhibitors, including imatinib. Here, we described the case of two 33-year-old men presenting with LyP and myeloid neoplasm with eosinophilia and FIP1L1::PDGFRA rearrangement who achieved complete clinical and molecular remission of both conditions a few months after starting imatinib.

Abl kinases can function as suppressors of tumor progression and metastasis

Introduction

Abl family kinases function as proto-oncogenes in various leukemias, and pro-tumor functions have been discovered for Abl kinases in many solid tumors as well. However, a growing body of evidence indicates that Abl kinases can function to suppress tumor cell proliferation and motility and tumor growth in vivo in some settings.

Methods

To investigate the role of Abl kinases in tumor progression, we used RNAi to generate Abl-deficient cells in a model of androgen receptor-indifferent, metastatic prostate cancer. The effect of Abl kinase depletion on tumor progression and metastasis was studied in an in vivo orthotopic model, and tumor cell motility, 3D growth, and signaling was studied in vitro.

Results

Reduced Abl family kinase expression resulted in a highly aggressive, metastatic phenotype in vivo that was associated with AKT pathway activation, increased growth on 3D collagen matrix, and enhanced cell motility in vitro. Inhibiting AKT pathway signaling abolished the increased 3D growth of Abl-deficient cells, while treatment with the Abl kinase inhibitor, imatinib, promoted 3D growth of multiple additional tumor cell types. Moreover, Abl kinase inhibition also promoted soft-agar colony formation by pre-malignant fibroblasts.

Conclusions

Collectively, our data reveal that Abl family kinases can function to suppress malignant cell phenotypes in vitro, and tumor progression and metastasis in vivo.

Pharmacokinetics of Four Tyrosine Kinase Inhibitors in Adult and Paediatric Chronic Myeloid Leukaemia Patients

Tyrosine kinase inhibitors work by blocking the tyrosine kinases responsible for the dysregulation of intracellular signalling pathways in tumour cells. This study looked at the impact of age and sex on the levels of imatinib, dasatinib, nilotinib, and ponatinib in plasma and cerebrospinal fluid samples of patients with chronic myeloid leukaemia. Imatinib and dasatinib were used to treat the majority of the enrolled patients, and most of them were paediatrics. A total of 82.4% of the patients were men; however, sex-related differences in the drugs' pharmacokinetics were not found. Age and imatinib plasma concentration were found to be inversely correlated. The dasatinib concentrations in plasma were found to be substantially lower than those found in cerebrospinal fluid, particularly in paediatrics. Analysing the obtained data, we can state that therapeutic drug monitoring is a useful method for adjusting a patient's treatment schedule that depends on drug concentrations in biological fluids. The use of therapeutic drug monitoring in conjunction with tyrosine kinase inhibitors for the treatment of chronic myeloid leukaemia is supported by a number of sources of evidence. As a result, as the research develops, the tyrosine kinase inhibitor therapeutic drug monitoring classification needs to be refined in terms of factors like sex and age.

Characterization of a Human Gastrointestinal Stromal Tumor Cell Line Established by SV40LT-Mediated Immortalization

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors in the digestive tract and originate from the interstitial cells of Cajal (ICC), which is the pacemaker for peristaltic movement in the gastrointestinal tract. Existing GIST cell lines are widely used as cell models for in vitro experimental studies because the mutation sites are known. However, the immortalization methods of these cell lines are unknown, and no Chinese patient-derived GIST cell lines have been documented. Here, we transfected simian virus 40 large T antigen (SV40LT) into primary GIST cells to establish an immortalized human GIST cell line (ImGIST) for the first time. The ImGIST cells had neuronal cell-like irregular radioactive growth and retained the fusion growth characteristics of GIST cells. They stably expressed signature proteins, maintained the biological and genomic characteristics of normal primary GIST cells, and responded well to imatinib, suggesting that ImGIST could be a potential in vitro model for research in GIST to explore the molecular pathogenesis, drug resistance mechanisms, and the development of new adjuvant therapeutic options.

Determinants of frontline tyrosine kinase inhibitor choice for patients with chronic-phase chronic myeloid leukemia: A study from the Registro Italiano LMC and Campus CML

BACKGROUND

Imatinib, dasatinib, and nilotinib are tyrosine kinase inhibitors (TKIs) approved in Italy for frontline treatment of chronic-phase chronic myeloid leukemia (CP-CML). The choice of TKI is based on a combined evaluation of the patient's and the disease characteristics. The aim of this study was to analyze the use of frontline TKI therapy in an unselected cohort of Italian patients with CP-CML to correlate the choice with the patient's features.

METHODS

A total of 1967 patients with CP-CML diagnosed between 2012 and 2019 at 36 centers throughout Italy were retrospectively evaluated; 1089 patients (55.4%) received imatinib and 878 patients (44.6%) received a second-generation (2G) TKI.

RESULTS

Second-generation TKIs were chosen for most patients aged <45 years (69.2%), whereas imatinib was used in 76.7% of patients aged >65 years (p < .001). There was a predominant use of imatinib in intermediate/high European long-term survival risk patients (60.0%/66.0% vs. 49.7% in low-risk patients) and a limited use of 2G-TKIs in patients with comorbidities such as hypertension, diabetes, chronic obstructive pulmonary disease, previous neoplasms, ischemic heart disease, or stroke and in those with >3 concomitant drugs. We observed a greater use of imatinib (61.1%) in patients diagnosed in 2018-2019 compared to 2012-2017 (53.2%; p = .002). In multivariable analysis, factors correlated with imatinib use were age > 65 years, spleen size, the presence of comorbidities, and ≥3 concomitant medications.

CONCLUSIONS

This observational study of almost 2000 cases of CML shows that imatinib is the frontline drug of choice in 55% of Italian patients with CP-CML, with 2G-TKIs prevalently used in younger patients and in those with no concomitant clinical conditions. Introduction of the generic formulation in 2018 seems to have fostered imatinib use.

Imatinib prevents dexamethasone-induced pancreatic β-cell apoptosis via decreased TRAIL and DR5

Prolonged administration of dexamethasone, a potent anti-inflammatory drug, can lead to steroid-induced diabetes. Imatinib, a medication commonly prescribed for chronic myeloid leukemia (CML), has been shown to improve diabetes in CML patients. Our recent study demonstrated that dexamethasone induces pancreatic β-cell apoptosis by upregulating the expression of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and its receptor, death receptor 5 (DR5). We hypothesized that imatinib may protect against dexamethasone-induced pancreatic β-cell apoptosis by reducing the expression of TRAIL and DR5, thereby favorably modulating downstream effectors in apoptotic pathways. We test this hypothesis by assessing the effects of imatinib on dexamethasone-induced apoptosis in rat insulinoma cell line cells. As anticipated, dexamethasone treatment led to increased TRAIL and DR5 expression, as well as an elevation in superoxide production. Conversely, expression of the TRAIL decoy receptor (DcR1) was decreased. Moreover, key effectors in the extrinsic and intrinsic apoptosis pathways, such as B-cell lymphoma 2 (BCL-2) associated X (BAX), nuclear factor kappa B (NF-κb), P73, caspase 8, and caspase 9, were upregulated, while the antiapoptotic protein BCL-2 was downregulated. Interestingly and importantly, imatinib at a concentration of 10 µM reversed the effect of dexamethasone on TRAIL, DR5, DcR1, superoxide production, BAX, BCL-2, NF-κB, P73, caspase 3, caspase 8, and caspase 9. Similar effects of imatinib on dexamethasone-induced TRAIL and DR5 expression were also observed in isolated mouse islets. Taken together, our findings suggest that imatinib protects against dexamethasone-induced pancreatic β-cell apoptosis by reducing TRAIL and DR5 expression and modulating downstream effectors in the extrinsic and intrinsic apoptosis pathways.

From KIT-mutated into wild-type: dedifferentiation of gastrointestinal stromal tumor in adolescent patient-a case report

Background

Gastrointestinal stromal tumor (GIST) is the most common mesenchymal neoplasm of the gastrointestinal tract, usually found in elderly adults. It is infrequent among pediatric patients and usually differs from adult-type disease in terms of histopathology and molecular features.

Case Description

We describe the management of the disease in a 10-year-old female patient diagnosed with a GIST of the stomach. In total, she has undergone successively total tumor resection, unsuccessful imatinib treatment and subtotal gastric resection at relapse. The first genetic test from primary tumor confirmed KIT mutations in exons 13 and 17, while the repeated genetic screening using tumor sample from subtotal gastric resection revealed no KIT or platelet-derived growth factor receptor α (PDGFRA) genes mutations. Such dedifferentiation from adult type (thus KIT-mutated) into wild-type (without KIT or PDGFRA mutation) has not been reported so far to the best of our knowledge. Currently, the patient is observed, and no further pharmacological nor surgical treatment has been administered.

Conclusions

The case underlines the importance of genetic profiling combined with non-standard diagnostics (both histopathological and radiological) due to the treatment efficacy prediction. We moreover emphasize the necessity to create worldwide standards on the diagnostics and treatment of GIST in pediatric patients that would include options of targeted therapies.

Tyrosine kinase inhibitors induced thyroid dysfunction: myth or reality?

Background

Chronic myelogenous leukemia (CML) is a hematopoietic stem cell disorder. It is associated with acquired genetic changes in the hematopoietic stem cells in the form of BCR-ABL fusion gene also known as Philadelphia chromosome.

Materials and methods

We prospectively studied thyroid function at baseline and at 6 months of imatinib treatment in 26 newly diagnosed BCR-ABL positive CML patients.

Result

The thyroid-stimulating hormone (TSH) levels increased significantly from baseline (3.20 ± 0.978 mIU/L vs. 3.724 ± 1.726 mIU/L, p < 0.05) after 6 months of treatment, 88.4% of the patients remained euthyroid. Only 2 patients had subclinical hypothyroidism, 1 had hypothyroidism after 6 months of tyrosine kinase inhibitors (TKI) therapy.

Conclusion

Imatinib did not have any significant effect on thyroid function in CML patients in this study.

2023 GEIS Guidelines for gastrointestinal stromal tumors

Gastrointestinal stromal tumor (GIST) is the most common malignant neoplasm of mesenchymal origin. GIST spans a wide clinical spectrum that ranges from tumors with essentially no metastatic potential to malignant and life-threatening spread diseases. Gain-of-function mutations in KIT or PDGFRA receptor tyrosine kinases are the crucial drivers of most GISTs, responsible for tumor initiation and evolution throughout the entire course of the disease. The introduction of tyrosine kinase inhibitors targeting these receptors has substantially improved the outcomes in this formerly chemoresistant cancer. As of today, five agents hold regulatory approval for the treatment of GIST: imatinib, sunitinib, regorafenib, ripretinib, and avapritinib. This, in turn, represents a success for a rare neoplasm. During the past two decades, GIST has become a paradigmatic model in cancer for multidisciplinary work, given the disease-specific particularities regarding tumor biology and tumor evolution. Herein, we review currently available evidence for the management of GIST. This clinical practice guideline has been developed by a multidisciplinary expert panel (oncologist, pathologist, surgeon, molecular biologist, radiologist, and representative of patients' advocacy groups) from the Spanish Group for Sarcoma Research, and it is conceived to provide, from a critical perspective, the standard approach for diagnosis, treatment, and follow-up.

Evaluation of Systemic Treatment Options for Gastrointestinal Stromal Tumours

Gastrointestinal stromal tumours (GIST) are the most common mesenchymal tumours of the gastrointestinal tract. Surgical treatment is recommended for the majority of localised GIST, while systemic treatment is the cornerstone of management for metastatic or unresectable disease. While a three-year regimen of imatinib is the standard of care in the adjuvant setting, there is no precise recommendation for the duration of neoadjuvant treatment, where imatinib is usually given between 4 and 12 months. Continuous treatment with imatinib at a dose of 400 mg once per day is recommended for most patients with unresectable or metastatic GIST in the first line. An exception is represented by patients with tumours harbouring the imatinib-insensitive PDGFRA D842V mutation who would be better treated with avapritinib. Targeted therapies are also recommended in the presence of NTRK rearrangements and BRAF mutations, although limited data are available. While an increase in the dose of imatinib to 800 mg is an option for the second line, sunitinib is usually considered the standard of care. Similar outcomes were reported for ripretinib in patients with tumours harbouring KIT exon 11 mutation, with significantly fewer side effects. Regorafenib and ripretinib are the standards of care in the third and fourth lines, respectively. The recent development of various systemic treatment options allows for a more personalised approach based on the molecular profile of the GIST, patient characteristics, and the profile of medications' adverse events. A multidisciplinary approach is paramount since combining systemic treatment with locoregional treatment options and supportive care is vital for long-term survival.

Pharmacology and Rationale for Seralutinib in the Treatment of Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a complex disorder characterized by vascular remodeling and a consequent increase in pulmonary vascular resistance. The histologic hallmarks of PAH include plexiform and neointimal lesions of the pulmonary arterioles, which are composed of dysregulated, apoptosis-resistant endothelial cells and myofibroblasts. Platelet-derived growth factor receptors (PDGFR) α and β, colony stimulating factor 1 receptor (CSF1R), and mast/stem cell growth factor receptor kit (c-KIT) are closely related kinases that have been implicated in PAH progression. In addition, emerging data indicate significant crosstalk between PDGF signaling and the bone morphogenetic protein receptor type 2 (BMPR2)/transforming growth factor β (TGFβ) receptor axis. This review will discuss the importance of the PDGFR-CSF1R-c-KIT signaling network in PAH pathogenesis, present evidence that the inhibition of all three nodes in this kinase network is a potential therapeutic approach for PAH, and highlight the therapeutic potential of seralutinib, currently in development for PAH, which targets these pathways.