Cereblon-Targeting Ligase Degraders in Myeloma: Mechanisms of Action and Resistance.

Cereblon-targeting degraders, including immunomodulatory imide drugs lenalidomide and pomalidomide alongside cereblon E3 ligase modulators like iberdomide and mezigdomide, have demonstrated significant anti-myeloma effects. These drugs play a crucial role in diverse therapeutic approaches for multiple myeloma (MM), emphasizing their therapeutic importance across various disease stages. Despite their evident efficacy, approximately 5% to 10% of MM patients exhibit primary resistance to lenalidomide, and resistance commonly develops over time. Understanding the intricate mechanisms of action and resistance to this drug class becomes imperative for refining and advancing novel therapeutic combinations.

Response of a Novel KANK1::ALK Fusion to Alectinib in an Advanced Lung Adenocarcinoma: A Case Report.

More than 90 distinct fusion partners of ALK rearrangement have been identified. Different ALK fusions may exhibit different sensitivities to ALK tyrosine kinase inhibitors. The emergence of rare fusions poses significant challenges to targeted therapies. This study aimed to investigate the response of KANK1::ALK fusion to alectinib in an advanced lung adenocarcinoma. A novel KANK1::ALK fusion was identified by next-generation sequencing (NGS) and Ventana immunohistochemistry assessments. A 73-year-old woman who had never smoked was admitted with hemoptysis in May 2020. PET/CT revealed a nodule in the left upper lobe, with bilateral pulmonary and multiple lymph node metastases. The upper lobe nodule of the left lung was diagnosed as adenocarcinoma through bronchofiberscopy biopsy, resulting in a clinical diagnosis of stage IVA (cT1c,N3,M1a). Because the biopsy tissue was insufficient for NGS analysis, a blood-based genetic analysis was performed, revealing the presence of KRAS p.Q61R mutations. The patient received carboplatin and pemetrexed with pembrolizumab as first-line therapy, followed by maintenance therapy of pembrolizumab monotherapy. Although the tumor initially showed significant shrinkage, it unfortunately progressed further after 11 months. Subsequently, the patient was given carboplatin and pemetrexed with pembrolizumab again, but the tumor progression continued. An NGS using a rebiopsy of the left upper lobe tumor suggested a KANK1::ALK fusion. Alectinib was prescribed in January 2022, and a durable partial response was observed after 18 months. ALK rearrangements were observed in the broader spectrum of lung cancers. This study provided a potential treatment option for patients with KANK1::ALK fusions. Further studies are needed to understand the function of these fusions.

A Case Report of Infant-Type Hemispheric Glioma with a Novel GAB1-ABL2 Kinase Fusion Treated with Dasatinib.

INTRODUCTION: Infant-type hemispheric glioma (IHG) is a rare form of cancer that affects newborns and infants. It is classified as a pediatric-type high-grade glioma and typically harbors receptor tyrosine kinase (RTK) gene fusions. Here, we present the finding of a novel gene fusion IHG treated with a targeted therapy that has yet to be implemented for any other IHG case to date. CASE PRESENTATION: We report the case of a 12-month-old boy with IHG who presented with obstructive hydrocephalus due to a large mass in the right frontal lobe. The patient initially underwent mass resection, but subsequent imaging showed rapid interval progression of the residual tumor. Comprehensive molecular analysis of the tumor tissue revealed a novel GAB1-ABL2 gene fusion, and the patient was started on dasatinib, an ABL kinase inhibitor. Shortly after initiation of dasatinib treatment, there was a significant reduction in tumor size and enhancement, followed by stabilization of disease. DISCUSSION: The patient's robust response to treatment suggests that dasatinib is an effective targeted therapy for IHG harboring a GAB1-ABL2 gene fusion. This finding may inform future investigations into the disease processes of IHG and help guide the diagnosis and treatment of IHG in the absence of previously identified gene fusions, improving clinical management of this vulnerable patient population.