Prolonged exposure to interferon-gamma (IFNγ) and the associated increased expression of the enzyme indoleamine 2,3-dioxygenase 1 (IDO1) create an intracellular shortage of tryptophan in the cancer cells, which stimulates ribosomal frameshifting and tryptophan to phenylalanine (W>F) codon reassignments during protein synthesis. Here, we investigated whether such neoepitopes can be useful targets of adoptive T cell therapy. Immunopeptidomic analyses uncovered hundreds of W>F neoepitopes mainly presented by the HLA-A24:02 allele.
View Article and Find Full Text PDFMalignant rhabdoid tumor (MRT) is one of the most aggressive childhood cancers for which no effective treatment options are available. Reprogramming of cellular metabolism is an important hallmark of cancer, with various metabolism-based drugs being approved as a cancer treatment. In this study, we use patient-derived tumor organoids (tumoroids) to map the metabolic landscape of several pediatric cancers.
View Article and Find Full Text PDFMessenger RNA (mRNA) translation is a tightly controlled process frequently deregulated in cancer. Key to this deregulation are transfer RNAs (tRNAs), whose expression, processing and post-transcriptional modifications are often altered in cancer to support cellular transformation. In conditions of limiting levels of amino acids, this deregulated control of protein synthesis leads to aberrant protein production in the form of ribosomal frameshifting or misincorporation of non-cognate amino acids.
View Article and Find Full Text PDFImpaired control of the G1/S checkpoint allows initiation of DNA replication under non-permissive conditions. Unscheduled S-phase entry is associated with DNA replication stress, demanding for other checkpoints or cellular pathways to maintain proliferation. Here, we uncovered a requirement for ADARp150 to sustain proliferation of G1/S-checkpoint-defective cells under growth-restricting conditions.
View Article and Find Full Text PDFOver 90% of pancreatic cancers present mutations in KRAS, one of the most common oncogenic drivers overall. Currently, most KRAS mutant isoforms cannot be targeted directly. Moreover, targeting single RAS downstream effectors induces adaptive resistance mechanisms.
View Article and Find Full Text PDFSomatic hotspot mutations and structural amplifications and fusions that affect fibroblast growth factor receptor 2 (encoded by FGFR2) occur in multiple types of cancer. However, clinical responses to FGFR inhibitors have remained variable, emphasizing the need to better understand which FGFR2 alterations are oncogenic and therapeutically targetable. Here we apply transposon-based screening and tumour modelling in mice, and find that the truncation of exon 18 (E18) of Fgfr2 is a potent driver mutation.
View Article and Find Full Text PDFCrosslink repair depends on the Fanconi anemia pathway and translesion synthesis polymerases that replicate over unhooked crosslinks. Translesion synthesis is regulated via ubiquitination of PCNA, and independently via translesion synthesis polymerase REV1. The division of labor between PCNA-ubiquitination and REV1 in interstrand crosslink repair is unclear.
View Article and Find Full Text PDFBackground: The majority of BRCA1-mutant breast cancers are characterized by a triple-negative phenotype and a basal-like molecular subtype, associated with aggressive clinical behavior. Current treatment options are limited, highlighting the need for the development of novel targeted therapies for this tumor subtype.
Methods: Our group previously showed that EZH2 is functionally relevant in BRCA1-deficient breast tumors and blocking EZH2 enzymatic activity could be a potent treatment strategy.
The enzyme glutaminyl-peptide cyclotransferase-like protein (QPCTL) catalyzes the formation of pyroglutamate residues at the NH-terminus of proteins, thereby influencing their biological properties. A number of studies have implicated QPCTL in the regulation of chemokine stability. Furthermore, QPCTL activity has recently been shown to be critical for the formation of the high-affinity SIRPα binding site of the CD47 "don't-eat-me" protein.
View Article and Find Full Text PDFCervical cancer is a common gynecological malignancy often caused by high-risk human papillomavirus. There is a paucity of human-derived culture systems to study the cervical epithelium and the cancers derived thereof. Here we describe a long-term culturing protocol for ecto- and endocervical epithelia that generates 3D organoids that stably recapitulate the two tissues of origin.
View Article and Find Full Text PDFL-asparaginase (ASNase) serves as an effective drug for adolescent acute lymphoblastic leukemia. However, many clinical trials indicated severe ASNase toxicity in patients with solid tumors, with resistant mechanisms not well understood. Here, we took a functional genetic approach and identified SLC1A3 as a novel contributor to ASNase resistance in cancer cells.
View Article and Find Full Text PDFOvarian cancer (OC) is a heterogeneous disease usually diagnosed at a late stage. Experimental in vitro models that faithfully capture the hallmarks and tumor heterogeneity of OC are limited and hard to establish. We present a protocol that enables efficient derivation and long-term expansion of OC organoids.
View Article and Find Full Text PDFSmall cell lung cancer (SCLC) is generally regarded as very difficult to treat, mostly due to the development of metastases early in the disease and a quick relapse with resistant disease. SCLC patients initially show a good response to treatment with the DNA damaging agents cisplatin and etoposide. This is, however, quickly followed by the development of resistant disease, which urges the development of novel therapies for this type of cancer.
View Article and Find Full Text PDFOrganoids are self-organizing 3D structures grown from stem cells that recapitulate essential aspects of organ structure and function. Here, we describe a method to establish long-term-expanding human airway organoids from broncho-alveolar resections or lavage material. The pseudostratified airway organoids consist of basal cells, functional multi-ciliated cells, mucus-producing secretory cells, and CC10-secreting club cells.
View Article and Find Full Text PDFThe defect in homologous recombination (HR) found in BRCA1-associated cancers can be therapeutically exploited by treatment with DNA-damaging agents and PARP inhibitors. We and others previously reported that BRCA1-deficient tumors are initially hypersensitive to the inhibition of topoisomerase I/II and PARP, but acquire drug resistance through restoration of HR activity by the loss of end-resection antagonists of the 53BP1/RIF1/REV7/Shieldin/CST pathway. Here, we identify radiotherapy as an acquired vulnerability of 53BP1;BRCA1-deficient cells and .
View Article and Find Full Text PDFKras-driven non-small-cell lung cancers (NSCLCs) are a leading cause of death with limited therapeutic options. Many NSCLCs exhibit high levels of Ezh2, the enzymatic subunit of polycomb repressive complex 2 (PRC2). We tested Ezh2 inhibitors as single agents or before chemotherapy in mice with orthotopic Kras-driven NSCLC grafts, which homogeneously express Ezh2.
View Article and Find Full Text PDFLung squamous cell carcinoma (LSCC) is a devastating malignancy with no effective treatments, due to its complex genomic profile. Therefore, preclinical models mimicking its salient features are urgently needed. Here we describe mouse models bearing various combinations of genetic lesions predominantly found in human LSCC.
View Article and Find Full Text PDFSmall cell lung cancer (SCLC) is an aggressive neuroendocrine tumor, and no effective treatment is available to date. Mouse models of SCLC based on the inactivation of Rb1 and Trp53 show frequent amplifications of the Nfib and Mycl genes. Here, we report that, although overexpression of either transcription factor accelerates tumor growth, NFIB specifically promotes metastatic spread.
View Article and Find Full Text PDFPolycomb repressive complexes (PRC) are frequently implicated in human cancer, acting either as oncogenes or tumor suppressors. Here, we show that PRC2 is a critical regulator of KRAS-driven non-small cell lung cancer progression. Modulation of PRC2 by either Ezh2 overexpression or Eed deletion enhances KRAS-driven adenomagenesis and inflammation, respectively.
View Article and Find Full Text PDFTumor heterogeneity can create a unique symbiotic tumor microenvironment. Earlier, we showed that clonal evolution in mouse small cell lung cancer (SCLC) can result in subclones that, upon cografting, endow the neuroendocrine tumor cells with metastatic potential. We now show that paracrine signaling between SCLC subclones is a critical requirement in the early steps of the metastatic process, such as local invasion and intravasation.
View Article and Find Full Text PDFClass I histone deacetylases are critical regulators of gene transcription by erasing lysine acetylation. Targeting histone deacetylases using relative non-specific small molecule inhibitors is of major interest in the treatment of cancer, neurological disorders and acquired immune deficiency syndrome. Harnessing the therapeutic potential of histone deacetylase inhibitors requires full knowledge of individual histone deacetylases in vivo.
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