- Mar 2021
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jmg.bmj.com jmg.bmj.com
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We then applied the p53 functional assay on blood samples sent to our laboratory for TP53 molecular analysis (NGS screening of the 11 exons complemented by QMPSF). Molecular and functional analyses were performed in parallel, in double blind conditions.
AssayGeneralClass: BAOCL:20:0010044 targeted transcriptional assay
AssayMaterialUsed: CL:2000001 peripheral blood mononuclear cell from patients
AssayDescription: Comparative transcriptomic analysis using reverse transcription to compare peripheral blood mononuclear cells of patients with wild type or pathogenic TP53 variants in the context of genotoxic stress induced by doxorubicin treatment. Ten biomarkers corresponding to p53 targets were measured to determine a functionality score.
AdditionalDocument: PMID: 23172776
AssayReadOutDescription: In the treated condition, the peak height of each of the 10 p53 target genes was measured and divided by the sum of the heights of the three control genes. This value was then divided by the same ratio calculated in the untreated condition. In the assay, the mean of the 10 values defines the p53 functionality score. The final p53 functionality score is the mean of the scores obtained in RT-MLPA and RT-QMPSF assays.
AssayRange: An arbitrary functionality score was calculated from the induction score of the 10 p53 targets.
AssayNormalRange: >7.5
AssayAbnormalRange: <5.5
AssayIndeterminateRange: Between 5.5 and 7.5 is associated with an intermediate effect.
AssayNormalControl: wild type TP53
AssayAbnormalControl: LFS patient cells
ValidationControlPathogenic: 8 individuals had seven distinct TP53 variants which could be considered as likely pathogenic or pathogenic based on their ClinVar classification or their truncating nature.
ValidationControlBenign: 51 individuals had no detectable germline TP53 variant
Replication: at least two wells were seeded per patient (treated and untreated) and duplicates or triplicates were performed whenever possible.
StatisticalAnalysisDescription: Differentially expressed genes between doxorubicin-treated and untreated cells were arbitrarily defined using, as filters, a P<0.01 and fold-change cutoffs >2 or <2, for up and down regulation, respectively. The resultant signal information was analyzed using one-way analysis of variance (ANOVA, P= 0.001), assuming normality but not equal variances with a Benjamani–Hochberg correction for multiple comparisons using three groups: controls, null, and missense mutations.
SignificanceThreshold: P=0.001
Comment: statistical analysis and P value from previous publication.
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We then applied the p53 functional assay on blood samples sent to our laboratory for TP53 molecular analysis (NGS screening of the 11 exons complemented by QMPSF). Molecular and functional analyses were performed in parallel, in double blind conditions.
AssayGeneralClass: BAOCL:20:0010044 targeted transcriptional assay
AssayMaterialUsed: CL:2000001 peripheral blood mononuclear cell from patients
AssayDescription: Comparative transcriptomic analysis using reverse transcription to compare peripheral blood mononuclear cells of patients with wild type or pathogenic TP53 variants in the context of genotoxic stress induced by doxorubicin treatment. p53 RNA levels were evaluated and expressed as a percentage of the mean levels obtained for the three wild-type TP53 individuals.
AdditionalDocument: PMID: 23172776
AssayReadOutDescription: The p53 mRNA levels were expressed as a ratio of the normal values obtained for 3 TP53 wild-type control individuals.
AssayRange: UO:0000187 the p53 RNA levels were evaluated and expressed as a percentage of the mean levels obtained for three wild-type TP53 individuals.
AssayNormalRange: >65%
AssayAbnormalRange: <65%
AssayIndeterminateRange: N/A
AssayNormalControl: wild type TP53
AssayAbnormalControl: LFS patient cells
ValidationControlPathogenic: 8 individuals had seven distinct TP53 variants which could be considered as likely pathogenic or pathogenic based on their ClinVar classification or their truncating nature.
ValidationControlBenign: 51 individuals had no detectable germline TP53 variant
Replication: at least two wells were seeded per patient (treated and untreated) and duplicates or triplicates were performed whenever possible.
StatisticalAnalysisDescription: Differentially expressed genes between doxorubicin-treated and untreated cells were arbitrarily defined using, as filters, a P<0.01 and fold-change cutoffs >2 or <2, for up and down regulation, respectively. The resultant signal information was analyzed using one-way analysis of variance (ANOVA, P= 0.001), assuming normality but not equal variances with a Benjamani–Hochberg correction for multiple comparisons using three groups: controls, null, and missense mutations.
SignificanceThreshold: P=0.001
Comment: statistical analysis and P value from previous publication.
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This new quantitative assay, based on both RT-QMPSF and RT-MLPA, was first validated on 31 lymphoblastoid cell lines derived from patients with LFS harbouring different germline heterozygous TP53 variants
AssayGeneralClass: BAO:0010044 targeted transcriptional assay
AssayMaterialUsed: BTO:0000773 lymphoblastoid cell line derived from control individuals or individuals with germline TP53 variants
AssayDescription: Comparative transcriptomic analysis using RNA-Seq to compare EBV cell lines of wild type and pathogenic TP53 in the context of genotoxic stress induced by doxorubicin treatment. p53 RNA levels were evaluated and expressed as a percentage of the mean levels obtained for the three wild-type TP53 individuals.
AdditionalDocument: PMID: 23172776
AssayReadOutDescription: The p53 mRNA levels were expressed as a ratio of the normal values obtained for 3 TP53 wild-type control individuals.
AssayRange: UO:0000187 the p53 RNA levels were evaluated and expressed as a percentage of the mean levels obtained for three wild-type TP53 individuals.
AssayNormalRange: N/A
AssayAbnormalRange: N/A
AssayIndeterminateRange: N/A
AssayNormalControl: wild type TP53
AssayAbnormalControl: LFS patient cells
ValidationControlPathogenic: 8 Individuals with dominant-negative TP53 missense variants, 10 Individuals with null TP53 variants, and 13 Individuals with other TP53 missense variants
ValidationControlBenign: 3 patients with wild type TP53
Replication: experiments were performed in triplicates.
StatisticalAnalysisDescription: Differentially expressed genes between doxorubicin-treated and untreated cells were arbitrarily defined using, as filters, a P<0.01 and fold-change cutoffs >2 or <2, for up and down regulation, respectively. The resultant signal information was analyzed using one-way analysis of variance (ANOVA, P= 0.001), assuming normality but not equal variances with a Benjamani–Hochberg correction for multiple comparisons using three groups: controls, null, and missense mutations.
SignificanceThreshold: P=0.001
Comment: statistical analysis and P value from previous publication.
-
This new quantitative assay, based on both RT-QMPSF and RT-MLPA, was first validated on 31 lymphoblastoid cell lines derived from patients with LFS harbouring different germline heterozygous TP53 variants
AssayGeneralClass: BAO:0010044 targeted transcriptional assay
AssayMaterialUsed: BTO:0000773 lymphoblastoid cell line derived from control individuals or individuals with germline TP53 variants
AssayDescription: Comparative transcriptomic analysis using RNA-Seq to compare EBV cell lines of wild type and pathogenic TP53 in the context of genotoxic stress induced by doxorubicin treatment. 10 biomarkers corresponding to p53 targets were measured to determine a functionality score.
AdditionalDocument: PMID: 23172776
AssayReadOutDescription: In the treated condition, the peak height of each of the 10 p53 target genes was measured and divided by the sum of the heights of the three control genes. This value was then divided by the same ratio calculated in the untreated condition. In the assay, the mean of the 10 values defines the p53 functionality score. The final p53 functionality score is the mean of the scores obtained in RT-MLPA and RT-QMPSF assays.
AssayRange: An arbitrary functionality score was calculated from the induction score of the 10 p53 targets.
AssayNormalRange: N/A
AssayAbnormalRange: N/A
AssayIndeterminateRange: N/A
AssayNormalControl: wild type TP53
AssayAbnormalControl: LFS patient cells
ValidationControlPathogenic: 8 Individuals with dominant-negative TP53 missense variants, 10 Individuals with null TP53 variants, and 13 Individuals with other TP53 missense variants
ValidationControlBenign: 3 patients with wild type TP53
Replication: experiments were performed in triplicates.
StatisticalAnalysisDescription: Differentially expressed genes between doxorubicin-treated and untreated cells were arbitrarily defined using, as filters, a P<0.01 and fold-change cutoffs >2 or <2, for up and down regulation, respectively. The resultant signal information was analyzed using one-way analysis of variance (ANOVA, P= 0.001), assuming normality but not equal variances with a Benjamani–Hochberg correction for multiple comparisons using three groups: controls, null, and missense mutations.
SignificanceThreshold: P=0.001
Comment: statistical analysis and P value from previous publication.
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- Feb 2021
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jmg.bmj.com jmg.bmj.com
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Identification of a germline pathogenic TP53 (MIM: *191170) variant in a patient with cancer has drastic medical impacts.
Gene: TP53
Disease: Li-Fraumeni Syndrome
MONDO: 0018875
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Blood functional assay for rapid clinical interpretation of germline TP53 variants
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