@article{MunawarZhouPrommersbergeretal.2023, author = {Munawar, Umair and Zhou, Xiang and Prommersberger, Sabrina and Nerreter, Silvia and Vogt, Cornelia and Steinhardt, Maximilian J. and Truger, Marietta and Mersi, Julia and Teufel, Eva and Han, Seungbin and Haertle, Larissa and Banholzer, Nicole and Eiring, Patrick and Danhof, Sophia and Navarro-Aguadero, Miguel Angel and Fernandez-Martin, Adrian and Ortiz-Ruiz, Alejandra and Barrio, Santiago and Gallardo, Miguel and Valeri, Antonio and Castellano, Eva and Raab, Peter and Rudert, Maximilian and Haferlach, Claudia and Sauer, Markus and Hudecek, Michael and Martinez-Lopez, J. and Waldschmidt, Johannes and Einsele, Hermann and Rasche, Leo and Kort{\"u}m, K. Martin}, title = {Impaired FADD/BID signaling mediates cross-resistance to immunotherapy in Multiple Myeloma}, series = {Communications Biology}, volume = {6}, journal = {Communications Biology}, doi = {10.1038/s42003-023-05683-4}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-357609}, year = {2023}, abstract = {The treatment landscape in multiple myeloma (MM) is shifting from genotoxic drugs to immunotherapies. Monoclonal antibodies, immunoconjugates, T-cell engaging antibodies and CART cells have been incorporated into routine treatment algorithms, resulting in improved response rates. Nevertheless, patients continue to relapse and the underlying mechanisms of resistance remain poorly understood. While Impaired death receptor signaling has been reported to mediate resistance to CART in acute lymphoblastic leukemia, this mechanism yet remains to be elucidated in context of novel immunotherapies for MM. Here, we describe impaired death receptor signaling as a novel mechanism of resistance to T-cell mediated immunotherapies in MM. This resistance seems exclusive to novel immunotherapies while sensitivity to conventional anti-tumor therapies being preserved in vitro. As a proof of concept, we present a confirmatory clinical case indicating that the FADD/BID axis is required for meaningful responses to novel immunotherapies thus we report impaired death receptor signaling as a novel resistance mechanism to T-cell mediated immunotherapy in MM.}, language = {en} } @article{HaertleBuenacheCuestaHernandezetal.2023, author = {Haertle, Larissa and Buenache, Natalia and Cuesta Hern{\´a}ndez, Hip{\´o}lito Nicol{\´a}s and Simicek, Michal and Snaurova, Renata and Rapado, Inmaculada and Martinez, Nerea and L{\´o}pez-Mu{\~n}oz, Nieves and S{\´a}nchez-Pina, Jos{\´e} Mar{\´i}a and Munawar, Umair and Han, Seungbin and Ruiz-Heredia, Yanira and Colmenares, Rafael and Gallardo, Miguel and Sanchez-Beato, Margarita and Piris, Miguel Angel and Samur, Mehmet Kemal and Munshi, Nikhil C. and Ayala, Rosa and Kort{\"u}m, Klaus Martin and Barrio, Santiago and Mart{\´i}nez-L{\´o}pez, Joaqu{\´i}n}, title = {Genetic alterations in members of the proteasome 26S subunit, AAA-ATPase (PSMC) gene family in the light of proteasome inhibitor resistance in multiple myeloma}, series = {Cancers}, volume = {15}, journal = {Cancers}, number = {2}, issn = {2072-6694}, doi = {10.3390/cancers15020532}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-305013}, year = {2023}, abstract = {For the treatment of Multiple Myeloma, proteasome inhibitors are highly efficient and widely used, but resistance is a major obstacle to successful therapy. Several underlying mechanisms have been proposed but were only reported for a minority of resistant patients. The proteasome is a large and complex machinery. Here, we focus on the AAA ATPases of the 19S proteasome regulator (PSMC1-6) and their implication in PI resistance. As an example of cancer evolution and the acquisition of resistance, we conducted an in-depth analysis of an index patient by applying FISH, WES, and immunoglobulin-rearrangement sequencing in serial samples, starting from MGUS to newly diagnosed Multiple Myeloma to a PI-resistant relapse. The WES analysis uncovered an acquired PSMC2 Y429S mutation at the relapse after intensive bortezomib-containing therapy, which was functionally confirmed to mediate PI resistance. A meta-analysis comprising 1499 newly diagnosed and 447 progressed patients revealed a total of 36 SNVs over all six PSMC genes that were structurally accumulated in regulatory sites for activity such as the ADP/ATP binding pocket. Other alterations impact the interaction between different PSMC subunits or the intrinsic conformation of an individual subunit, consequently affecting the folding and function of the complex. Interestingly, several mutations were clustered in the central channel of the ATPase ring, where the unfolded substrates enter the 20S core. Our results indicate that PSMC SNVs play a role in PI resistance in MM.}, language = {en} } @article{DaViaSolimandoGaritanoTrojaolaetal.2019, author = {Da Vi{\`a}, Matteo Claudio and Solimando, Antonio Giovanni and Garitano-Trojaola, Andoni and Barrio, Santiago and Munawar, Umair and Strifler, Susanne and Haertle, Larissa and Rhodes, Nadine and Vogt, Cornelia and Lapa, Constantin and Beilhack, Andreas and Rasche, Leo and Einsele, Hermann and Kort{\"u}m, K. Martin}, title = {CIC Mutation as a Molecular Mechanism of Acquired Resistance to Combined BRAF-MEK Inhibition in Extramedullary Multiple Myeloma with Central Nervous System Involvement}, series = {The Oncologist}, volume = {25}, journal = {The Oncologist}, number = {2}, doi = {10.1634/theoncologist.2019-0356}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-219549}, pages = {112-118}, year = {2019}, abstract = {Combined MEK-BRAF inhibition is a well-established treatment strategy in BRAF-mutated cancer, most prominently in malignant melanoma with durable responses being achieved through this targeted therapy. However, a subset of patients face primary unresponsiveness despite presence of the activating mutation at position V600E, and others acquire resistance under treatment. Underlying resistance mechanisms are largely unknown, and diagnostic tests to predict tumor response to BRAF-MEK inhibitor treatment are unavailable. Multiple myeloma represents the second most common hematologic malignancy, and point mutations in BRAF are detectable in about 10\% of patients. Targeted inhibition has been successfully applied, with mixed responses observed in a substantial subset of patients mirroring the widespread spatial heterogeneity in this genomically complex disease. Central nervous system (CNS) involvement is an extremely rare, extramedullary form of multiple myeloma that can be diagnosed in less than 1\% of patients. It is considered an ultimate high-risk feature, associated with unfavorable cytogenetics, and, even with intense treatment applied, survival is short, reaching less than 12 months in most cases. Here we not only describe the first patient with an extramedullary CNS relapse responding to targeted dabrafenib and trametinib treatment, we furthermore provide evidence that a point mutation within the capicua transcriptional repressor (CIC) gene mediated the acquired resistance in this patient.}, language = {en} } @phdthesis{Munawar2020, author = {Munawar, Umair}, title = {Functional analysis of oncogenic lesions in multiple myeloma with potential significance for refractory disease}, doi = {10.25972/OPUS-21644}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-216446}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2020}, abstract = {Despite the advancement in the treatment from genotoxic drugs to more targeted therapies, multiple myeloma (MM) remains incurable. MM is known for its complex genetic heterogeneity as different genetic lesion accrue over the course of the disease. The current work focuses on the functional analysis of genetic lesions found at the time of diagnosis and relapse and their potential role regarding therapy response and refractory disease. Genetic lesions involving tumor suppressor gene TP53, are found at diagnosis and tend to accrue during disease progression. Different types of mono- and biallelic TP53 alterations were emulated in the AMO1 cell line model, were functionally characterized and tested for their potential role in therapy response. Both types of single hit TP53 alteration (deletion 17p and TP53 point mutations) were found to have similar adverse effects on the functionality of the p53 system and response to genotoxic drugs which were completely abolished in the case of double hit TP53 alterations (no p53 expression, or mutant overexpression in wild type TP53 deletion background). Whereas, sensitivity to proteasome inhibitors remained unaltered. Using the clonal competition assay (CCA), single TP53 hit clones were found to have a fitness advantage over wildtype cells. Proliferative cell fitness was further enhanced in double hit TP53 clones, as they dominated wildtype and single hit TP53 clones in the CCA. Presence of external selection pressure in the form of low dose melphalan expedited the intrinsic fitness advantage. Alterations found in CUL4B, a component of CRL4-CRBN protein complex, a target of immunomodulatory drugs (IMiDs), were also functionally analyzed in the current study. Hotspot mutations and mutations found in IMiDs refractory patients were modelized in L363 cells and their role in IMiDs sensitivity was studied. CUL4B mutations were found not to be involved in providing lenalidomide resistance to the cell, whereas knocking CUL4B out was observed to provide negative fitness to the cells in CCA. In the presence of external selection pressure, these clones showed fitness, which was lost in the case of lenalidomide withdrawal. This shows that some alterations may play a role in refractory patients only in the presence of therapy, and as soon as therapy is discontinued, these altered clones may disappear such as clones with alterations in CUL4B. On the other hand, some alterations provide drug-independent intrinsic positive fitness, however, be further enhanced by drug exposure, such as seen in case of TP53 altered clones. Therefore, close monitoring and functional analysis of evolving clones is desired during disease progression, as it can be helpful in therapeutic guidance to achieve a better outcome for patients.}, subject = {TP53}, language = {en} }