scholarly journals TP53 Mutations Negatively Impact Survival of Acute Myeloid Leukemia Patients Treated with Standard Doses of Azacitidine

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 2745-2745
Author(s):  
Pierre Bories ◽  
Naïs Prade ◽  
Stéphanie Lagarde ◽  
Bastien Cabarrou ◽  
Julien Plenecassagnes ◽  
...  
Keyword(s):  
Missense Mutation ◽  
Tp53 Mutation ◽  
Response Rates ◽  
Classification Systems ◽  
Mutant P53 ◽  
Median Score ◽  
Functional Impact ◽  
Tp53 Mutations

Abstract Validated therapies for older pts with AML could rely on intensive or low-intensity strategies. Patient selection for these options remains controversial. There is currently no validated biomarker which can been used to guide therapeutic decision. TP53 mutations which are known to negatively impact AML pts outcome when treated with ICT, have been recently described as a positive prognosis factor for blast clearance with a 10-days regimen of decitabine (Welch, NEJM 2016). To date, it remains unclear whether AML pts with TP53 mutation represent a clinically homogeneous group. Several classification systems of p53 mutant, derived from in vitro or in vivo data, have been validated in solid tumors and aggressive lymphomas as predictors of p53 mutant functional impact or patient outcome. We retrospectively evaluated the impact of TP53 mutational status on the outcome of a real-world cohort of pts, treated frontline with standard doses of azacitidine (AZA). We further hypothesized that functional characterization of TP53 mutations could define a subgroup of pts with specific outcome with AZA From Jan 2007 to Dec 2016, we identified 279 AML pts enrolled in the regional cancer network ONCOMIP registry, treated frontline with AZA. Median age was 76 yrs (45-93), karyotype was adverse in 135 pts (49.1%), including 54 pts with -17 or del17p (19.4%). AML was secondary to MDS in 71 pts (25.4%), to MPN in 24 (8.6%) and therapy related in 46 pts (16.5%). Pts received a median of 6 cycles (1-67). Overall, 54 pts obtained CR/CRi (19.4%) and median OS was 10.6 months (95%CI ,9.7-12.1). For 224 pts with an available bone marrow baseline DNA sample, TP53 mutations were screened with next-generation sequencing on an Illumina® MiSeq sequencer. Sequencing results were filtered with the IARC TP53 mutations database and a variant allele frequency (VAF) >10%, strengthening the specificity of the data of this cohort. Of the 224 analyzed cases, 55 cases (24.6%) contained TP53 mutations. Response rates did not significantly differ between TP53mut (21.8% CR/CRi) and TP53wt (17.8% CR/CRi, p=.50) nor between pts with TP53mut and/or -17/del17p (19.1% CR/CRi) and pts without TP53 abnormality (18.6%CR/CRi, p=.93). Median OS was 7.9 months in pts with TP53mut and 12.6 months in TP53wt (p<.0001). With regards to the group of 109 pts with adverse karyotype, response rates did not significantly differ between TP53mut pts (20.8% CR/CRi) and TP53wt (14.3%, p=.37) and median OS was 7.9 months for TP53mut pts versus 9.6 for TP53wt pts (p=.02) Among the 55 pts with TP53mut, 53pts had adverse cytogenetics (96.4%), 16 pts had secondary AML to MDS or MPN (29.1%) and 13 had t-AML (23.6%). This subgroup included 49 cases (89%) with single TP53 mutation (missense n=42, nonsense n= 3, frameshift n=4) and 6 cases (11%) with 2 mutations (2 pts with missense and frameshift mutations and 4 pts with 2 missense mutation). We further characterized TP53mut pts with 3 validated classification systems. Due to dominant negative effect of TP53 mutation, for pts with >1 TP53 mutation, we selected the mutation with the predicted highest impact: 15 pts had disruptive mutations (i.e. missense mutation in L2/L3 helix of the DNA binding domain or truncating mutation) versus 40 pts with non-disruptive mutations (Poeta M, NEJM 2007), which was not associated with clinical response (25% in CR/CRi vs 27.9% in failure; p=1.00) nor with 6mOS (46.7% vs 55%, respectively; p=.79)Mutant p53 transactivation activity assessed with a 0-100 evolutionary score (Neskey D, Cancer Research 2015), was not associated with response (median score of 79.3[28-90] in CR/CRi vs 73.3 [49-96] in failure, p=1.00) nor with OS (HR 1.01; 95% CI, 0.99-1.03, p=.51).Relative fitness score (on a log2 scale) which was recently reported as a proxy of p53 mutant in vitro and in vivo cell proliferation advantage (Kotler E, Molecular cell 2018) was not associated with response (median score in CR/CRi of 0.094 [-0.79-0.58] vs 0.094 [-2.52-0.84] in failure, p=.68) nor with OS (HR 0.75; 95% CI, 0.45-1.22, p=.24) Overall, the response rate was not influenced by the TP53mut status, but median OS was negatively impacted by the TP53mut status in the entire cohort and in the sub-group of pts with adverse karyotype. None of the mutant p53 classification systems validated in other neoplasms succeed in identifying a subset of AML pts who specifically benefit from AZA suggesting a rather homogenous functional impact of TP53 mutations in this setting Disclosures Fornecker: Takeda: Honoraria; Servier: Honoraria.

scholarly journals Trans-splicing repair of mutant p53 suppresses the growth of hepatocellular carcinoma cells in vitro and in vivo

2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Xingxing He ◽  
Fang Liu ◽  
Jingjun Yan ◽  
Yunan Zhang ◽  
Junwei Yan ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Carcinoma Cells ◽  
Mutant P53 ◽  
Hepatocellular Carcinoma Cells ◽  
Trans Splicing

scholarly journals Targeting mutant p53-expressing tumours with a T cell receptor-like antibody specific for a wild-type antigen

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Lionel Low ◽  
Angeline Goh ◽  
Joanna Koh ◽  
Samantha Lim ◽  
Cheng-I Wang
Keyword(s):  
Cell Receptor ◽  
Class I ◽  
Human Antibody ◽  
Mutant P53 ◽  
Wild Type ◽  
Class I Mhc ◽  
Type Antigen ◽  
Wide Range

AbstractAccumulation of mutant p53 proteins is frequently found in a wide range of cancers. While conventional antibodies fail to target intracellular proteins, proteosomal degradation results in the presentation of p53-derived peptides on the tumour cell surface by class I molecules of the major histocompatibility complex (MHC). Elevated levels of such p53-derived peptide-MHCs on tumour cells potentially differentiate them from healthy tissues. Here, we report the engineering of an affinity-matured human antibody, P1C1TM, specific for the unmutated p53125-134 peptide in complex with the HLA-A24 class I MHC molecule. We show that P1C1TM distinguishes between mutant and wild-type p53 expressing HLA-A24+ cells, and mediates antibody dependent cellular cytotoxicity of mutant p53 expressing cells in vitro. Furthermore, we show that cytotoxic PNU-159682-P1C1TM drug conjugates specifically inhibit growth of mutant p53 expressing cells in vitro and in vivo. Hence, p53-associated peptide-MHCs are attractive targets for the immunotherapy against mutant p53 expressing tumours.

scholarly journals CP-31398 Restores DNA-binding Activity to Mutant p53in Vitrobut Does Not Affect p53 Homologs p63 and p73

2004 ◽  
Vol 279 (44) ◽  
pp. 45887-45896 ◽  
Author(s):  
Mark J. Demma ◽  
Serena Wong ◽  
Eugene Maxwell ◽  
Bimalendu Dasmahapatra
Keyword(s):  
Dna Binding ◽  
Mammalian Cells ◽  
P53 Protein ◽  
Binding Activity ◽  
Mutant P53 ◽  
Dependent Manner ◽  
Wild Type ◽  
Dna Binding Activity

The p53 protein plays a major role in the maintenance of genome stability in mammalian cells. Mutations of p53 occur in over 50% of all cancers and are indicative of highly aggressive cancers that are hard to treat. Recently, there has been a high degree of interest in therapeutic approaches to restore growth suppression functions to mutant p53. Several compounds have been reported to restore wild type function to mutant p53. One such compound, CP-31398, has been shown effectivein vivo, but questions have arisen to whether it actually affects p53. Here we show that mutant p53, isolated from cells treated with CP-31398, is capable of binding to p53 response elementsin vitro. We also show the compound restores DNA-binding activity to mutant p53 in cells as determined by a chromatin immunoprecipitation assay. In addition, using purified p53 core domain from two different hotspot mutants (R273H and R249S), we show that CP-31398 can restore DNA-binding activity in a dose-dependent manner. Using a quantitative DNA binding assay, we also show that CP-31398 increases significantly the amount of mutant p53 that binds to cognate DNA (Bmax) and its affinity (Kd) for DNA. The compound, however, does not affect the affinity (Kdvalue) of wild type p53 for DNA and only increasesBmaxslightly. In a similar assay PRIMA1 does not have any effect on p53 core DNA-binding activity. We also show that CP-31398 had no effect on the DNA-binding activity of p53 homologs p63 and p73.

Adoptive Infusion of Allogeneic KIR Ligand Mismatched NK Cells Reduce GVHD in an MHC Matched Allogeneic Stem Cell Transplantation Model.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 1310-1310
Author(s):  
Andreas Lundqvist ◽  
Leigh Samsel ◽  
Michael Eckhaus ◽  
Ramaprasad Srinivasan ◽  
Yoshiyuki Takahashi ◽  
...  
Keyword(s):  
T Cell ◽  
Nk Cells ◽  
Murine Model ◽  
Nk Cell ◽  
Allogeneic Transplantation ◽  
Allogeneic Bone ◽  
Median Score ◽  
The Impact

Abstract Retrospective data suggest NK cells play a role in protecting recipients from graft versus host disease (GVHD) in the setting of killer IgG-like receptor (KIR) ligand incompatibility. In humans, this protective effect is most evident with MHC mismatched transplantation, usually following in vivo or in vitro T-cell depletion. In MHC mismatched murine transplant models, lethal GVHD is reduced following the adoptive infusion of KIR ligand mismatched NK cells; it is unknown whether NK cells can mediate similar protective effects following MHC matched transplantation. Therefore, we investigated the impact of adoptively infusing KIR ligand mismatched NK cells on GVHD in an MHC matched T-cell replete murine model of allogeneic transplantation. Balb/C recipient mice underwent allogeneic bone marrow (8 x 106 cells) and splenocyte (15 x 106 cells) transplantation from B10.d2 donors following 950cGy of irradiation. Allogeneic B10.d2 donor NK cells were first isolated by negative depletion using magnetic beads selecting for CD4, CD5, CD8a, CD19, Gr-1 and Ter-119, and then expanded over 4-6 days in vitro in DMEM media containing 10% FCS and 500U/ml of IL-2. NK cell subsets (KIR ligand matched vs. KIR ligand mismatched) were then isolated by flow cytometry into Ly49I/C+ NK cells (KIR ligand mismatched in the GVHD direction for Balb/C recipients) and Ly49A/G+ NK cells (KIR ligand matched for Balb/C recipients). On day +4, recipient mice received a single tail vein injection with either KIR ligand matched, KIR ligand mismatched or unsorted “bulk” NK cells (0.5–1.0 x 106 NK cells). All (9/9) control transplant recipients (no adoptive NK cell infusion) as well as recipients of Ly49A/G (KIR ligand matched) NK cells (13/13) developed skin GVHD, in contrast to 4/7 (57%, p=0.03) recipients of bulk NK cells and only a minority (13% [1/8], p &lt; 0.01) of animals receiving KIR ligand mismatched NK cells. Using a cumulative clinical GVHD scoring system (total score = 9), overall GVHD was decreased in recipients of KIR ligand mismatched NK cells (median score = 0 at day +45) compared to mice that received KIR ligand matched NK cells (median score = 3; p = 0.15) or no NK cells (median score = 3; p= 0.12); no significant difference in survival was observed between cohorts. This murine model provides the first in vivo evidence that adoptively infused KIR ligand mismatched allogeneic NK cells reduce GVHD following T-cell replete MHC matched allogeneic transplantation. The impact of infusing multiple doses of KIR ligand mismatched NK cells on GVHD and their ability to induce a graft-vs-tumor effect in tumor bearing Balb/c mice is currently being evaluated.

scholarly journals Mutation of the α-tubulin Tuba1a leads to straighter microtubules and perturbs neuronal migration

2017 ◽  
Vol 216 (8) ◽  
pp. 2443-2461 ◽  
Author(s):  
Richard Belvindrah ◽  
Kathiresan Natarajan ◽  
Preety Shabajee ◽  
Elodie Bruel-Jungerman ◽  
Jennifer Bernard ◽  
...  
Keyword(s):  
Missense Mutation ◽  
Glial Cells ◽  
Neuronal Migration ◽  
Cortical Malformations ◽  
Tubulin Isotype ◽  
Modeling Data ◽  
Migratory Stream ◽  
Β Tubulin

Brain development involves extensive migration of neurons. Microtubules (MTs) are key cellular effectors of neuronal displacement that are assembled from α/β-tubulin heterodimers. Mutation of the α-tubulin isotype TUBA1A is associated with cortical malformations in humans. In this study, we provide detailed in vivo and in vitro analyses of Tuba1a mutants. In mice carrying a Tuba1a missense mutation (S140G), neurons accumulate, and glial cells are dispersed along the rostral migratory stream in postnatal and adult brains. Live imaging of Tuba1a-mutant neurons revealed slowed migration and increased neuronal branching, which correlated with directionality alterations and perturbed nucleus–centrosome (N–C) coupling. Tuba1a mutation led to increased straightness of newly polymerized MTs, and structural modeling data suggest a conformational change in the α/β-tubulin heterodimer. We show that Tuba8, another α-tubulin isotype previously associated with cortical malformations, has altered function compared with Tuba1a. Our work shows that Tuba1a plays an essential, noncompensated role in neuronal saltatory migration in vivo and highlights the importance of MT flexibility in N–C coupling and neuronal-branching regulation during neuronal migration.

scholarly journals PAPSS2 Deficiency Causes Androgen Excess via Impaired DHEA Sulfation—In Vitro and in Vivo Studies in a Family Harboring Two Novel PAPSS2 Mutations

2015 ◽  
Vol 100 (4) ◽  
pp. E672-E680 ◽  
Author(s):  
Wilma Oostdijk ◽  
Jan Idkowiak ◽  
Jonathan W. Mueller ◽  
Philip J. House ◽  
Angela E. Taylor ◽  
...  
Keyword(s):  
Polycystic Ovary Syndrome ◽  
Polycystic Ovary ◽  
Challenge Test ◽  
Compound Heterozygous ◽  
Androgen Excess ◽  
Ovary Syndrome ◽  
Functional Impact ◽  
Low Serum

Context: PAPSS2 (PAPS synthase 2) provides the universal sulfate donor PAPS (3′-phospho-adenosine-5′-phosphosulfate) to all human sulfotransferases, including SULT2A1, responsible for sulfation of the crucial androgen precursor dehydroepiandrosterone (DHEA). Impaired DHEA sulfation is thought to increase the conversion of DHEA toward active androgens, a proposition supported by the previous report of a girl with inactivating PAPSS2 mutations who presented with low serum DHEA sulfate and androgen excess, clinically manifesting with premature pubarche and early-onset polycystic ovary syndrome. Patients and Methods: We investigated a family harboring two novel PAPSS2 mutations, including two compound heterozygous brothers presenting with disproportionate short stature, low serum DHEA sulfate, but normal serum androgens. Patients and parents underwent a DHEA challenge test comprising frequent blood sampling and urine collection before and after 100 mg DHEA orally, with subsequent analysis of DHEA sulfation and androgen metabolism by mass spectrometry. The functional impact of the mutations was investigated in silico and in vitro. Results: We identified a novel PAPSS2 frameshift mutation, c.1371del, p.W462Cfs*3, resulting in complete disruption, and a novel missense mutation, c.809G&gt;A, p.G270D, causing partial disruption of DHEA sulfation. Both patients and their mother, who was heterozygous for p.W462Cfs*3, showed increased 5α-reductase activity at baseline and significantly increased production of active androgens after DHEA intake. The mother had a history of oligomenorrhea and chronic anovulation that required clomiphene for ovulation induction. Conclusions: We provide direct in vivo evidence for the significant functional impact of mutant PAPSS2 on DHEA sulfation and androgen activation. Heterozygosity for PAPSS2 mutations can be associated with a phenotype resembling polycystic ovary syndrome.

scholarly journals Adoptive cell therapy targeting common p53 neoantigens in human solid cancers

2021 ◽  
Author(s):  
Sanghyun Kim ◽  
Nolan Vale ◽  
Nikolaos Zacharakis ◽  
Sri Krishna ◽  
Zhiya Yu ◽  
...  
Keyword(s):  
Cell Therapy ◽  
Tumor Regression ◽  
Ex Vivo ◽  
Adoptive Cell Therapy ◽  
Peripheral Blood Lymphocytes ◽  
Mutant P53 ◽  
Autologous Tumor ◽  
Clinical Responses

Abstract Adoptive cell therapy (ACT) targeting neoantigens can achieve durable clinical responses in patients with cancer. Most neoantigens arise from rare mutations, requiring highly individualized treatments. To broaden the applicability of ACT targeting neoantigens, we focused on TP53 mutations commonly shared across different cancer types. Here, we describe a library of T cell receptors (TCRs) that can target TP53 mutations shared among 7.3% of patients with solid cancers. These TCRs recognized tumor cells in a TP53 mutation- and human leucocyte antigen (HLA)-specific manner both in vitro and in vivo. Patients with chemorefractory epithelial cancers treated with ex vivo-expanded autologous tumor infiltrating lymphocytes (TILs) naturally reactive with mutant p53 experienced limited clinical responses (2 PRs/12 patients), and we detected low frequencies, exhausted phenotypes, and poor persistence of the infused mutant p53-reactive TILs. Alternatively, we treated one patient with a chemorefractory breast cancer with ACT by transducing autologous peripheral blood lymphocytes with an HLA-A*02-restricted anti-p53R175H TCR. The infused cells exhibited an improved immunophenotype and prolonged persistence compared to the TIL ACT and the patient experienced an objective tumor regression (-55%) that lasted 6 months. Collectively, these data demonstrate the feasibility of off-the-shelf TCR-engineered cell therapies targeting shared p53 neoantigens to treat human cancers.

scholarly journals Sex- and Mutation-Specific p53 Gain-of-Function Activity in Gliomagenesis

2021 ◽  
Vol 1 (3) ◽  
pp. 148-163
Author(s):  
Nathan C. Rockwell ◽  
Wei Yang ◽  
Nicole M. Warrington ◽  
Max V. Staller ◽  
Malachi Griffith ◽  
...  
Keyword(s):  
Sex Differences ◽  
Dna Binding ◽  
Sex Difference ◽  
P53 Mutation ◽  
Mutant P53 ◽  
Missense Mutations ◽  
P53 Mutations ◽  
Primary Mouse

In cancer, missense mutations in the DNA-binding domain of TP53 are common. They abrogate canonical p53 activity and frequently confer gain-of-oncogenic function (GOF) through localization of transcriptionally active mutant p53 to noncanonical genes. We found that several recurring p53 mutations exhibit a sex difference in frequency in patients with glioblastoma (GBM). In vitro and in vivo analysis of three mutations, p53R172H, p53Y202C, and p53Y217C, revealed unique interactions between cellular sex and p53 GOF mutations that determined each mutation's ability to transform male versus female primary mouse astrocytes. These phenotypic differences were correlated with sex- and p53 mutation–specific patterns of genomic localization to the transcriptional start sites of upregulated genes belonging to core cancer pathways. The promoter regions of these genes exhibited a sex difference in enrichment for different transcription factor DNA-binding motifs. Together, our data establish a novel mechanism for sex-specific mutant p53 GOF activity in GBM with implications for all cancer. Significance: Sex differences in cancer, including glioblastoma, have been observed in both incidence and outcome. We reveal that TP53, the most commonly mutated gene in cancer, contributes to sex differences through differential GOF activity. This discovery has critical implications for our understanding of p53 mutations and the importance of sex as a biological variable.

Safety, efficacy, and pharmacodynamics of the investigational agent orteronel (TAK-700) in metastatic castration-resistant prostate cancer (mCRPC): Updated data from a phase I/II study.

2012 ◽  
Vol 30 (5_suppl) ◽  
pp. 98-98 ◽  
Author(s):  
David B. Agus ◽  
Walter Michael Stadler ◽  
Daniel H. Shevrin ◽  
Lowell Hart ◽  
Gary R. MacVicar ◽  
...  
Keyword(s):  
Phase 1 ◽  
Specific Antigen ◽  
Response Rates ◽  
Similar Efficacy ◽  
Castration Resistant Prostate Cancer ◽  
Open Label ◽  
Investigational Agent ◽  
Psa Response

98 Background: The investigational agent orteronel (TAK-700) is a selective 17,20 lyase inhibitor that down regulates androgenic steroid production in vitro and in vivo. Since phase 1 data in patients (pts) with mCRPC were promising, this open-label, multicenter study was expanded to gather additional data on safety and antitumor activity. Methods: The phase 2 portion of this study included four additional dose cohorts. Pts had no prior chemotherapy, and had baseline testosterone <50 ng/dL and prostate-specific antigen (PSA) ≥5 ng/mL. Results: 97 pts received orteronel 300 mg BID (n=23), 400 mg BID + prednisone 5 mg BID (n=24), 600 mg BID + prednisone (n=26), or 600 mg QD (n=24). At data cut-off (23 May 2011), 62% of pts had withdrawn (including 19% due to AEs and 19% for disease progression [PD]). Most common AEs were fatigue (76%), nausea (47%), and constipation (38%); most common grade ≥3 AEs were fatigue (12%) and hypokalaemia (8%). PSA response rates (≥50% decrease) at 12 wks were 63%, 50%, 41%, and 60% in the 300 mg BID, 400 and 600 mg BID + prednisone, and 600 mg QD groups. Of 51 RECIST-evaluable pts, 10 had partial responses (of which 5 confirmed), 22 stable disease, and 15 PD. At 12 wks, median testosterone decreased from baseline in all groups: (ng/dL, 12 wks/baseline) 0.98/8.50 (300 mg BID), 0.30/9.90 (400 mg BID +prednisone), 0.07/7.33 (600 mg BID + prednisone), 0.49/6.31 (600 mg QD). Similarly, at 12 wks, median dehydroepiandrosterone sulfate (DHEA-S) decreased from baseline in all groups: (µg/dL, 12 wks/baseline) 8.65/53.0 (300 mg BID), 0.10/36.3 (400 mg BID + prednisone), 0.10/51.7 (600 mg BID + prednisone), 5.30/31.5 (600 mg QD). Overall, mean circulating tumor cell numbers decreased from 16.6 (per 7.5mL blood) at baseline to 3.9 at 12 wks. Conclusions: Orteronel ≥300 mg BID appears active and well tolerated in pts with mCRPC, with similar efficacy ± prednisone. PSA response rates suggest that testosterone, rather than DHEA, may be a more reliable marker of lyase inhibition efficacy. Preclinical data and changes in pharmacodynamic parameters in this study suggest partially selective 17,20 lyase inhibition. Final data will be reported.

Characterization of mutant p53-hsp72/73 protein-protein complexes by transient expression in monkey COS cells

1988 ◽  
Vol 8 (9) ◽  
pp. 3740-3747
Author(s):  
H W Stürzbecher ◽  
C Addison ◽  
J R Jenkins
Keyword(s):  
Complex Formation ◽  
Protein Complexes ◽  
P53 Protein ◽  
Simian Virus 40 ◽  
Simian Virus ◽  
T Antigen ◽  
Mutant P53 ◽  
Cos Cells

Several mutant, but not wild-type, p53 proteins form complexes with hsp72/73 heat shock-related proteins in simian virus 40-transformed monkey COS cells. We carried out a detailed biochemical and structural mapping analysis of p53 and report here that p53-hsp72/73 complex formation showed considerable structural specificity. Such complexes were remarkably stable, but unlike analogous complexes formed between p53 and simian virus 40 T antigen, they did not form in in vitro association assays. p53-hsp72/73 complex formation in vivo appears to be dependent on aspects of mutant p53 protein conformation. However, absence of the conformation-sensitive epitope recognized by monoclonal antibody PAb 246 was not reliably diagnostic of such complexes, nor was p53-hsp72173 binding reliably diagnostic of oncogenic activation.

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