Concomitant imatinib and ibrutinib in a patient with chronic myelogenous leukemia and chronic lymphocytic leukemia

BTK acts as a modulator of the response to imatinib in chronic myeloid leukemia

The use of tyrosine kinase inhibitors, such as imatinib, against the chronic myeloid leukemia (CML)-causing kinase BCR::ABL1 has become the model for successful targeted therapy. Nevertheless, drug resistance remains a clinical problem. Analysis of genome-wide expression and genetic aberrations of an in vitro imatinib-resistant CML cell line revealed downregulation of Bruton's tyrosine kinase (BTK), predominantly associated with B cell malignancies, and a novel BTK kinase domain variant in imatinib resistance. This raised the question of the role of BTK in imatinib-resistant CML. In the present study, BTK downregulation and the presence of the BTK variant c.1699_1700delinsAG p.(Glu567Arg) were confirmed in imatinib resistance in vitro. Similarly, BTK inhibition or small interfering RNA-mediated BTK knockdown reduced imatinib susceptibility by 84 and 71%, respectively. BTK overexpression was detrimental to CML cells, as proliferation was significantly reduced by 20.5% under imatinib treatment. In addition, BTK rescue in imatinib-resistant cells restored imatinib sensitivity. The presence of the BTK p.(Glu567Arg) variant increased cell numbers (57%) and proliferation (37%) under imatinib exposure. These data demonstrate that BTK is important for the development of imatinib resistance in CML: Its presence increased drug response, while its absence promotes imatinib resistance. Moreover, the BTK p.(Glu567Arg) variant abrogates imatinib sensitivity. These findings demonstrate a context-dependent role for BTK as an oncogene in B cell malignancies, but as a tumor suppressor in other neoplasms.

Concomitant Venetoclax and Imatinib for Comanaging Chronic Lymphocytic Leukemia and Chronic Myeloid Leukemia: A Case Report

Patients with synchronous malignancies can be problematic to diagnose and manage because workup and therapeutic targeting for each individual malignancy must be coordinated carefully. This report presents a patient with concurrent chronic myeloid leukemia (CML) and chronic lymphocytic leukemia (CLL) managed with concomitant venetoclax and imatinib. Because imatinib is a moderate cytochrome P450 3A4 inhibitor, close monitoring is required when using with a substrate of 3A4 such as venetoclax. Although the target dose of venetoclax is 400 mg, it was capped at 100 mg due to the interaction. Despite the interaction and possible enhancement of toxicities, the patient has tolerated therapy well, and both diseases have responded to this novel approach. In addition, because aberrant BCL-2 activity has been implicated in CML, the use of venetoclax may contribute to success in the management of this patient's CML. This case report represents the safe concomitant use of venetoclax and imatinib in a patient with synchronous CML and CLL.

Machine learning enabled identification of potential SARS-CoV-2 3CLpro inhibitors based on fixed molecular fingerprints and Graph-CNN neural representations

AIM

Rapidly developing AI and machine learning (ML) technologies can expedite therapeutic development and in the time of current pandemic their merits are particularly in focus. The purpose of this study was to explore various ML approaches for molecular property prediction and illustrate their utility for identifying potential SARS-CoV-2 3CLpro inhibitors.

MATERIALS AND METHODS

We perform a series of drug discovery screenings based on supervised ML models operating in different ways on molecular representations, encompassing shallow learning methods based on fixed molecular fingerprints, Graph Convolutional Neural Network (Graph-CNN) with its self-learned molecular representations, as well as ML methods based on combining fixed and Graph-CNN learned representations.

RESULTS

Results of our ML models are compared both with respect to the aggregated predictive performance in terms of ROC-AUC based on the scaffold splits, as well as on the granular level of individual predictions, corresponding to the top ranked repurposing candidates. This comparison reveals both certain characteristic homogeneity regarding chemical and pharmacological classification, with a prevalence of sulfonamides and anticancer drugs, as well as identifies novel groups of potential drug candidates against COVID-19.

CONCLUSIONS

A series of ML approaches for molecular property prediction enables drug discovery screenings, illustrating the utility for COVID-19. We show that the obtained results correspond well with the already published research on COVID-19 treatment, as well as provide novel insights on potential antiviral characteristics inferred from in vitro data.

Chronic Myelogenous Leukemia Diagnosed in the Setting of Untreated Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma

Chronic myeloid leukemia (CML) is rarely reported to occur in treated chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). In this article, we report a woman in her 70s, diagnosed with CLL/SLL in 2000, untreated, who subsequently presented 12 years later with de novo CML, BCR-ABL1+. Her IGHV mutated CLL/SLL based on the initial sample in our laboratory showed homozygous and heterozygous 13q14.3 deletions, whereas her CML, at presentation, showed a 46,XX,t(9;22)(q34;q11.2)[7]/46,XX[18] karyotype with a p190 BCR-ABL1 transcript. The tumor burden of each clone varied with treatment, including when treated with dasatinib, used to target both clones. In addition, the cytogenetic abnormalities evolved over time and treatments and included acquisition of an extra chromosome 8 in the CML clone and a novel K1992T ATM missense mutation (47% allele frequency) in the CLL/SLL clone. The patient's last bone marrow biopsy, 5 years after her CML diagnosis and 17 years after the CLL/SLL diagnosis, showed residual CML with extensive involvement by CLL/SLL (80%). Cytogenetic studies showed a 46,XX karyotype, while FISH identified 13q14.3 deletion and the BCR-ABL1 translocation in the CLL/SLL and CML clones, respectively. To date, this is the fourth case of concurrent CML, BCR-ABL1+ arising in untreated CLL/SLL. Here we show dynamic variation in the size of the 2 clonal processes reflecting the variable responsiveness to specific therapies. In addition to the unusual BCR-ABL1+ p190 transcript in the patient's CML, a novel ATM K1992T mutation was identified in the CLL/SLL population.