RESUMEN
The identification of targetable vulnerabilities in the context of therapeutic resistance is a key challenge in cancer treatment. We detected pervasive aberrant splicing as a characteristic feature of chronic lymphocytic leukemia (CLL), irrespective of splicing factor mutation status, which was associated with sensitivity to the spliceosome modulator, E7107. Splicing modulation affected CLL survival pathways, including members of the B cell lymphoma-2 (BCL2) family of proteins, remodeling antiapoptotic dependencies of human and murine CLL cells. E7107 treatment decreased myeloid cell leukemia-1 (MCL1) dependence and increased BCL2 dependence, sensitizing primary human CLL cells and venetoclax-resistant CLL-like cells from an Eµ-TCL1-based adoptive transfer murine model to treatment with the BCL2 inhibitor venetoclax. Our data provide preclinical rationale to support the combination of venetoclax with splicing modulators to reprogram apoptotic dependencies in CLL for treating venetoclax-resistant CLL cases.
Asunto(s)
Empalme Alternativo/efectos de los fármacos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Compuestos Epoxi/farmacología , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Macrólidos/farmacología , Sulfonamidas/farmacología , Adulto , Anciano , Anciano de 80 o más Años , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Apoptosis/efectos de los fármacos , Apoptosis/genética , Compuestos Bicíclicos Heterocíclicos con Puentes/uso terapéutico , Modelos Animales de Enfermedad , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Ensayos de Selección de Medicamentos Antitumorales , Compuestos Epoxi/uso terapéutico , Femenino , Humanos , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/patología , Macrólidos/uso terapéutico , Masculino , Ratones , Ratones Transgénicos , Persona de Mediana Edad , Mitocondrias/efectos de los fármacos , Mitocondrias/patología , Mutación , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/antagonistas & inhibidores , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Fosfoproteínas/genética , Cultivo Primario de Células , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-bcl-2/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Pirimidinas/farmacología , Pirimidinas/uso terapéutico , Factores de Empalme de ARN/genética , Empalmosomas/efectos de los fármacos , Empalmosomas/metabolismo , Sulfonamidas/uso terapéutico , Tiofenos/farmacología , Tiofenos/uso terapéuticoRESUMEN
Determining the effect of chemotherapeutic treatment on changes in protein expression can provide important targets for overcoming resistance. Due to challenges in simultaneously measuring large numbers of proteins, a paucity of data exists on global changes. To overcome these challenges, we utilized microwestern arrays that allowed us to measure the abundance and modification state of hundreds of cell signaling and transcription factor proteins in cells following drug exposure. HapMap lymphoblastoid cell lines (LCLs) were exposed to cisplatin, a chemotherapeutic agent commonly used to treat testicular, head and neck, non-small cell lung, and gynecological cancers. We evaluated the expression of 259 proteins following 2, 6, and 12 h of cisplatin treatment in two LCLs with discordant sensitivity to cisplatin. Of these 259 proteins, 66 displayed significantly different protein expression changes (p < 0.05). Fifteen of these proteins were evaluated in a second pair of LCLs with discordant sensitivities to cisplatin; six demonstrated significant differences in expression. We then evaluated a subset of 63 proteins in a second set of LCLs with discordant sensitivity, and 40% of those that were significant in the first pair were also significant in the second part with concordant directionality (p < 0.05). We functionally validated one of the top proteins identified, PDK1, and demonstrated a synergistic relationship between cisplatin and a PDK1 inhibitor in multiple lung cancer lines. This study highlights the potential for identifying novel targets through an understanding of cellular changes in protein expression and modification following drug treatments.