Genetic screens discover proteases as synthetic lethal partners of PI3K inhibition in breast cancer cells
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus Homo sapiens
PROVIDER: GSE186196 | GEO | 2021/12/31
REPOSITORIES: GEO
Similar Datasets
Project description:RationalePI3K/mTOR signaling is frequently upregulated in breast cancer making inhibitors of this pathway highly promising anticancer drugs. However, PI3K-inhibitors have a low therapeutic index. Therefore, finding novel combinatory treatment options represents an important step towards clinical implementation of PI3K pathway inhibition in breast cancer therapy. Here, we propose proteases as potential synergistic partners with simultaneous PI3K inhibition in breast cancer cells.MethodsWe performed mRNA expression studies and unbiased functional genetic synthetic lethality screens by a miR-E based knockdown system targeting all genome-encoded proteases, i.e. the degradome of breast cancer cells. Importantly theses RNA interference screens were done in combination with two PI3K pathway inhibitors. Protease hits were validated in human and murine breast cancer cell lines as well as in non-cancerous cells by viability and growth assays.ResultsThe degradome-wide genetic screens identified 181 proteases that influenced susceptibility of murine breast cancer cells to low dose PI3K inhibition. Employing independently generated inducible knockdown cell lines we validated 12 protease hits in breast cancer cells. In line with the known tumor promoting function of these proteases we demonstrated Usp7 and Metap2 to be important for murine and human breast cancer cell growth and discovered a role for Metap1 in this context. Most importantly, we demonstrated that Usp7, Metap1 or Metap2 knockdown combined with simultaneous PI3K inhibition resulted in synergistic impairment of murine and human breast cancer cell growth Conclusion: We successfully established proteases as combinatory targets with PI3K inhibition in human and murine breast cancer cells. Usp7, Metap1 and Metap2 are synthetic lethal partners of simultaneous protease/PI3K inhibition, which may refine future breast cancer therapy.
| S-EPMC9169373 | biostudies-literature
Project description:Genetic screens discover proteases as synthetic lethal partners of PI3K inhibition in breast cancer cells
| PRJNA772940 | ENA
Project description:Accurate chromosome segregation requires the execution and coordination of many processes during mitosis, including DNA replication, sister chromatid cohesion, and attachment of chromosomes to spindle microtubules via the kinetochore complex. Additional pathways are likely involved because faithful chromosome segregation also requires proteins that are not physically associated with the chromosome. Using kinetochore mutants as a starting point, we have identified genes with roles in chromosome stability by performing genome-wide screens employing synthetic genetic array methodology. Two genetic approaches (a series of synthetic lethal and synthetic dosage lethal screens) isolated 211 nonessential deletion mutants that were unable to tolerate defects in kinetochore function. Although synthetic lethality and synthetic dosage lethality are thought to be based upon similar genetic principles, we found that the majority of interactions associated with these two screens were nonoverlapping. To functionally characterize genes isolated in our screens, a secondary screen was performed to assess defects in chromosome segregation. Genes identified in the secondary screen were enriched for genes with known roles in chromosome segregation. We also uncovered genes with diverse functions, such as RCS1, which encodes an iron transcription factor. RCS1 was one of a small group of genes identified in all three screens, and we used genetic and cell biological assays to confirm that it is required for chromosome stability. Our study shows that systematic genetic screens are a powerful means to discover roles for uncharacterized genes and genes with alternative functions in chromosome maintenance that may not be discovered by using proteomics approaches.
| S-EPMC1236538 | biostudies-literature
Project description:Epstein-Barr virus (EBV) causes endemic Burkitt lymphoma and immunosuppression-related lymphomas. These B-cell malignancies arise by distinct transformation pathways and utilize divergent viral and host expression programs. To identify host dependency factors elicited by EBV latent-infection states, we performed parallel genome-wide CRISPR/Cas9 screens in Burkitt lymphoma (BL) and lymphoblasotid cell lines (LCL). Our results highlighted 57 BL and 87 LCL genes selectively critical for their growth and survival. LCL hits were enriched for EBV-induced genes, including viral super-enhancer targets and multiple kinases. We uncovered key CD19/CD81 roles in EBV membrane protein-driven PI3K/AKT activation and mechanisms by which EBV evades tumor suppressor responses to its growth program. LMP1-induced cFLIP was critical for LCL defense against TNFa-mediated programmed cell death, while EBV-induced BATF/IRF4 were critical for LCL BIM suppression and MYC induction. EBV super-enhancer targeted IRF2 protected LCLs against BLIMP1 responses. Collectively, our results identify host/pathogen interaction-driven synthetic lethal targets for therapeutic intervention.
2017-05-11 | GSE93681 | GEO
Project description:BRCA1 or BRCA2 inactivation drives breast and ovarian cancer but also creates vulnerability to poly(ADP-ribose) polymerase (PARP) inhibitors. To search for additional targets whose inhibition is synthetically lethal in BRCA2-deficient backgrounds, we screened two pairs of BRCA2 isogenic cell lines with DNA-repair-focused small hairpin RNA (shRNA) and CRISPR (clustered regularly interspaced short palindromic repeats)-based libraries. We found that BRCA2-deficient cells are selectively dependent on multiple pathways including base excision repair, ATR signaling, and splicing. We identified APEX2 and FEN1 as synthetic lethal genes with both BRCA1 and BRCA2 loss of function. BRCA2-deficient cells require the apurinic endonuclease activity and the PCNA-binding domain of Ape2 (APEX2), but not Ape1 (APEX1). Furthermore, BRCA2-deficient cells require the 5' flap endonuclease but not the 5'-3' exonuclease activity of Fen1, and chemically inhibiting Fen1 selectively targets BRCA-deficient cells. Finally, we developed a microhomology-mediated end-joining (MMEJ) reporter and showed that Fen1 participates in MMEJ, underscoring the importance of MMEJ as a collateral repair pathway in the context of homologous recombination (HR) deficiency.
| S-EPMC6892393 | biostudies-literature
Project description:The development of cancer therapies is limited by the availability of suitable drug targets. Potential candidate drug targets can be identified based on the concept of synthetic lethality (SL), which refers to pairs of genes for which an aberration in either gene alone is non-lethal, but co-occurrence of the aberrations is lethal to the cell. Here, we present SLIdR (Synthetic Lethal Identification in R), a statistical framework for identifying SL pairs from large-scale perturbation screens. SLIdR successfully predicts SL pairs even with small sample sizes while minimizing the number of false positive targets. We apply SLIdR to Project DRIVE data and find both established and potential pan-cancer and cancer type-specific SL pairs consistent with findings from literature and drug response screening data. We experimentally validate two predicted SL interactions (ARID1A-TEAD1 and AXIN1-URI1) in hepatocellular carcinoma, thus corroborating the ability of SLIdR to identify potential drug targets.
| S-EPMC9751287 | biostudies-literature
Project description:This SuperSeries is composed of the SubSeries listed below.
2024-04-24 | GSE219141 | GEO
Project description:Neurofibromatosis Type II is a genetic condition caused by loss of the NF2 gene, resulting in activation of the YAP/TAZ pathway and recurrent growth of benign tumors from Schwann cells, the glia of the peripheral nervous system. Unfortunately, no pharmacological therapy is currently available for NFII. Here, we undertake a genome-wide CRISPR/cas9 screen to search for synthetic-lethal genes that, when inhibited, cause death of NF2 mutant cells but not NF2 wildtype cells. We thereby identify ACSL3 and G6PD as two synthetic-lethal partners for NF2. We find that NF2 mutant Schwann cells are vulnerable to G6PD inhibition because they have low levels of ME1. G6PD and ME1 redundantly generate cytosolic NADPH needed by cells to fight oxidative stress. Lack of either one of the two is compatible with cell viability, but down-regulation of both leads to Schwann cell death. Since genetic deficiency for G6PD is tolerated in the human population, this raises the possibility that G6PD could be a pharmacological target for NFII.
2024-04-24 | GSE219136 | GEO
Project description:Neurofibromatosis Type II is a genetic condition caused by loss of the NF2 gene, resulting in activation of the YAP/TAZ pathway and recurrent growth of benign tumors from Schwann cells, the glia of the peripheral nervous system. Unfortunately, no pharmacological therapy is currently available for NFII. Here, we undertake a genome-wide CRISPR/cas9 screen to search for synthetic-lethal genes that, when inhibited, cause death of NF2 mutant cells but not NF2 wildtype cells. We thereby identify ACSL3 and G6PD as two synthetic-lethal partners for NF2. We find that NF2 mutant Schwann cells are vulnerable to G6PD inhibition because they have low levels of ME1. G6PD and ME1 redundantly generate cytosolic NADPH needed by cells to fight oxidative stress. Lack of either one of the two is compatible with cell viability, but down-regulation of both leads to Schwann cell death. Since genetic deficiency for G6PD is tolerated in the human population, this raises the possibility that G6PD could be a pharmacological target for NFII.
2024-04-24 | GSE219135 | GEO
Project description:Mutated KRAS plays an important role in many cancers. Although targeting KRAS directly is difficult, indirect inactivation via synthetic lethal partners (SLPs) is promising. Yet to date, there are no SLPs from high-throughput RNAi screening, which are supported by multiple screens. Here, we address this problem by aggregating and ranking data over three independent high-throughput screens. We integrate rankings by minimizing the displacement and by considering established methods such as RIGER and RSA.Our meta analysis reveals COPB2 as a potential SLP of KRAS with good support from all three screens. COPB2 is a coatomer subunit and its knock down has already been linked to disabled autophagy and reduced tumor growth. We confirm COPB2 as SLP in knock down experiments on pancreas and colorectal cancer cell lines.Overall, consistent integration of high throughput data can generate candidate synthetic lethal partners, which individual screens do not uncover. Concretely, we reveal and confirm that COPB2 is a synthetic lethal partner of KRAS and hence a promising cancer target. Ligands inhibiting COPB2 may, therefore, be promising new cancer drugs.
| S-EPMC5470967 | biostudies-literature