Recent data demonstrate that extracellular signals are transmitted through a network of proteins rather than hierarchical signaling pathways. This network model suggests why inhibition of a single component of a canonical pathway, even when targeting a mutationally activated driver of cancer, has insufficiently dramatic effects on the treatment of cancer. The biological outcome of signals propagated through a network is inherently more robust and resistant to inhibition of a single network component due to compensatory and redundant signaling events. In this study, we performed a functional chemical genetic screen analogous to synthetic lethal screening in yeast genetics to identify novel interactions between signaling inhibitors that would not be predicted based on our current understanding of signaling networks. We screened over 300 drug combinations in nine melanoma cell lines and have identified pairs of compounds that show synergistic cytotoxicity. Among the most robust and surprising results was synergy between sorafenib, a multi-kinase inhibitor with activity against Raf, and diclofenac, a non-steroidal anti-inflammatory drug (NSAID). This synergy did not correlate with the known RAS and BRAF mutational status of the melanoma cell lines. The NSAIDs celecoxib and ibuprofen could qualitatively substitute for diclofenac. Similarly, the MEK inhibitor PD325901 and the Raf inhibitor RAF265 could qualitatively substitute for sorafenib. These drug substitution experiments suggest that inhibition of cyclo-oxygenase and MAP kinase signaling are components of the observed synergistic cytotoxicity. Genome-wide expression profiling demonstrates synergy-specific down-regulation of survival-related genes. This study provides proof of principle that synthetic lethal screening can uncover novel functional drug combinations and suggests that the underlying signaling networks that control responses to targeted agents can vary substantially depending on unexplored components of the cell genotype.
Synthetic lethal screening with small-molecule inhibitors provides a pathway to rational combination therapies for melanoma.
Cell line, Treatment
View SamplesGene expression analysis identified a CRC related signature of differentially expressed genes discriminating patients Responder and Non Responder to radiochemotherapy
A functional biological network centered on XRCC3: a new possible marker of chemoradiotherapy resistance in rectal cancer patients.
Sex, Age, Specimen part, Disease, Disease stage
View SamplesTranscriptomic comparison of FVB mouse strain lung Cells one week upon injecting mice intraperitoneally with either saline or Urethane. Mouse lung cell were also compared at the transcriptomic level with the mouse lung adenocarcinoma cell line FULA 1, which was established in our lab
IκB Kinase α Is Required for Development and Progression of <i>KRAS</i>-Mutant Lung Adenocarcinoma.
Specimen part, Cell line, Treatment
View SamplesWe compared different mouse cancer cell lines to identify their unique cell signatures.
Myeloid-derived interleukin-1β drives oncogenic KRAS-NF-κΒ addiction in malignant pleural effusion.
Cell line, Treatment
View SamplesWe compared different mouse cancer cell lines to identify their unique cell signatures.
<i>NRAS</i> destines tumor cells to the lungs.
Specimen part, Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
MicroRNAs cooperatively inhibit a network of tumor suppressor genes to promote pancreatic tumor growth and progression.
Specimen part, Subject
View SamplesmiRNAs are known to be involved in PDAC tumorigenesis, but only a few biologically relevant gene targets have been identified.
MicroRNAs cooperatively inhibit a network of tumor suppressor genes to promote pancreatic tumor growth and progression.
Specimen part, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Inactivation of the budding yeast cohesin loader Scc2 alters gene expression both globally and in response to a single DNA double strand break.
No sample metadata fields
View SamplesGenome integrity is fundamental for cell survival and cell cycle progression. Important mechanisms for keeping the genome intact are proper sister chromatid segregation, correct gene regulation and efficient repair of damaged DNA. Cohesin and its DNA loader, the Scc2/4 complex have been implicated in all these cellular actions. The gene regulation role has been described in several organisms. In yeast it has been suggested that the proteins in the cohesin network would effect transcription based on its role as insulator. More recently, data are emerging indicating direct roles for gene regulation also in yeast. Here we extend these studies by investigating whether the cohesin loader Scc2 is involved in regulation of gene expression. We performed global gene expression profiling in the absence and presence of DNA damage, in wild type and Scc2 deficient G2/M arrested cells, when it is known that Scc2 is important for DNA double strand break repair and formation of damage induced cohesion. We found that not only the DNA damage specific transcriptional response is distorted after inactivation of Scc2, but also the overall transcription profile. Interestingly, these alterations did not correlate with changes in cohesin binding.
Inactivation of the budding yeast cohesin loader Scc2 alters gene expression both globally and in response to a single DNA double strand break.
No sample metadata fields
View SamplesGermline mutations of the SMARCB1 gene predispose to two distinct tumor syndromes: rhabdoid tumor predisposition syndrome, with malignant pediatric tumors mostly developing in brain and kidney, and familial schwannomatosis, with adulthood benign tumors involving cranial and peripheral nerves. The mechanisms by which SMARCB1 germline mutations predispose to rhabdoid tumors versus schwannomas are still unknown. Here, to understand the origin of these two types of SMARCB1-associated tumors, we generated different tissue- and developmental stage-specific conditional knockout mice carrying Smarcb1 and/or Nf2 deletion. Smarcb1 loss in early neural crest was necessary to initiate tumorigenesis in the cranial nerves and meninges with typical histological features and molecular profiles of human rhabdoid tumors. By inducing Smarcb1 loss at later developmental stage in the Schwann cell lineage, in addition to biallelic Nf2 gene inactivation, we generated the first mouse model developing schwannomas with the same underlying gene mutations found in schwannomatosis patients. Overall design: RNA-sequencing of 12 Smarcb1-deficient mouse cranial nerves and meninges tumors
Timing of Smarcb1 and Nf2 inactivation determines schwannoma versus rhabdoid tumor development.
Specimen part, Subject
View Samples