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Differential selective pressure alters rate of drug resistance acquisition in heterogeneous tumor populations.

ABSTRACT: Recent drug discovery and development efforts have created a large arsenal of targeted and chemotherapeutic drugs for precision medicine. However, drug resistance remains a major challenge as minor pre-existing resistant subpopulations are often found to be enriched at relapse. Current drug design has been heavily focused on initial efficacy, and we do not fully understand the effects of drug selective pressure on long-term drug resistance potential. Using a minimal two-population model, taking into account subpopulation proportions and growth/kill rates, we modeled long-term drug treatment and performed parameter sweeps to analyze the effects of each parameter on therapeutic efficacy. We found that drugs with the same overall initial kill may exert differential selective pressures, affecting long-term therapeutic outcome. We validated our conclusions experimentally using a preclinical model of Burkitt's lymphoma. Furthermore, we highlighted an intrinsic tradeoff between drug-imposed overall selective pressure and rate of adaptation. A principled approach in understanding the effects of distinct drug selective pressures on short-term and long-term tumor response enables better design of therapeutics that ultimately minimize relapse.

SUBMITTER: Sun D

PROVIDER: S-EPMC5098152 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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Differential selective pressure alters rate of drug resistance acquisition in heterogeneous tumor populations.

Sun Daphne D Dalin Simona S Hemann Michael T MT Lauffenburger Douglas A DA Zhao Boyang B

Scientific reports 20161107

Recent drug discovery and development efforts have created a large arsenal of targeted and chemotherapeutic drugs for precision medicine. However, drug resistance remains a major challenge as minor pre-existing resistant subpopulations are often found to be enriched at relapse. Current drug design has been heavily focused on initial efficacy, and we do not fully understand the effects of drug selective pressure on long-term drug resistance potential. Using a minimal two-population model, taking ...[more]

PMID: 27819268

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Project description:Inherited and de novo genomic imbalances at chromosome 16p11.2 are associated with autism spectrum disorders (ASD), but the causative genes remain unknown. Among the genes located in this region, PRRT2 codes for a member of the synaptic SNARE complex that allows the release of synaptic vesicles. PRRT2 is a candidate gene for ASD since homozygote mutations are associated with intellectual disability and heterozygote mutations cause benign infantile seizures, paroxysmal dyskinesia, or hemiplegic migraine. Here, we explored the contribution of PRRT2 mutations in ASD by screening its coding part in a large sample of 1578 individuals including 431 individuals with ASD, 186 controls and 961 individuals from the human genome Diversity Panel. We detected 24 nonsynonymous variants, 1 frameshift (A217PfsX8) and 1 in-frame deletion of 6 bp (p.A361_P362del). The frameshift mutation was observed in a control with no history of neurological or psychiatric disorders. The p.A361_P362del was observed in two individuals with autism from sub-Saharan African origin. Overall, the frequency of PRRT2 deleterious variants was not different between individuals with ASD and controls. Remarkably, PRRT2 displays a highly significant excess of nonsynonymous (pN) vs synonymous (pS) mutations in Asia (pN/pS = 4.85) and Europe (pN/pS = 1.62) compared with Africa (pN/pS = 0.26; Asia vs Africa: P = 0.000087; Europe vs Africa P = 0.00035; Europe vs Asia P = P = 0.084). We also showed that whole genome amplification performed through rolling cycle amplification could artificially introduce the A217PfsX8 mutation indicating that this technology should not be performed prior to PRRT2 mutation screening. In summary, our results do not support a role for PRRT2 coding sequence variants in ASD, but provide an ascertainment of its genetic variability in worldwide populations that should help researchers and clinicians to better investigate the role of PRRT2 in human diseases.

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Dataset Information

Differential selective pressure alters rate of drug resistance acquisition in heterogeneous tumor populations.

Publications

Differential selective pressure alters rate of drug resistance acquisition in heterogeneous tumor populations.

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