Determination of Both TP53 Mutation Status and the Amount of p53 Protein Has Limited Diagnostic Importance for Patients with Ovarian Cancer

Background: Ovarian cancer is one of the most aggressive types of gynecologic cancers. Many patients have a relapse within two years after diagnosis and subsequent therapy. Among different genetic changes generally believed to be important for the development of cancer, TP53 is the most common mutation in the case of ovarian tumors. Objective: Our work aims to compare the outcomes of different comparisons based on the overall survival of ovarian cancer patients, determination of TP53 status, and amount of p53 protein in tumor tissues. Methods: We analyzed and compared a collective of 436 ovarian patient’s data. Extracted data include TP53 mutation status, p53 protein level, and information on the overall survival. Values for p53 protein level in dependence of TP53 mutation status were compared using the Independent-Samples t-Test. Survival analyses were displayed by Kaplan-Meier plots, using the log-rank test to check for statistical significance. Results: We have not found any statistically significant correlations between determination of TP53 status, amount of p53 protein in tumor tissues, and overall survival of ovarian cancer patients. Conclusion: In ovarian tumors both determination of TP53 status as well as p53 protein amount has only limited diagnostic importance.

A Novel Lipid Prognostic Signature of ADCY2, LIPE, and OLR1 in Head and Neck Squamous Cell Carcinoma

Simple SummaryClinically, aberrant lipid metabolism is responsible for overweight and/or obesity. Overweight is considered as an independent factor of cancer risk in 2019. Therefore, lipid metabolic reprogramming is an emerging hallmark of malignancy. It is an urgent need to comprehensively understand the relationship among lipid metabolism and HNSCC and identify a valuable biomarker for predicting prognosis of HNSCC patients. Three new findings were found in this study. Firstly, we identified the lipid-related differentially expressed genes (DEGs) by using the GEO microarrays and TCGA dataset. A novel lipid-related mRNA prognostic signature (LRPS, consisting of ADCY2, LIPE and OLR1) was developed, which could predict the survival and prognosis of HNSCC patients as an independent effective prognostic factor. Secondly, we found that the LRPS could indicate the type of infiltrated immune cells in HNSCC tumor microenvironment. Thirdly, we verified that the LPPS score could interpret the TP53 status of HNSCC. Our new findings indicated that LRPS has a potential to be a promising indicator of overall survival, TP53 status, and immune characteristics in HNSCC, and perhaps can monitor and guide the treatment efficacy and prognosis of HNSCC in the future.BackgroundHead and neck squamous cell carcinoma (HNSCC) is characterized by a high frequency of lymph node metastasis and a high mortality. Lipid metabolic reprogramming is an emerging carcinogen as its role in fulfilling cancer growth and spread. However, little is known about the correlation between lipid metabolism and HNSCC.Materials and MethodsExpressions of lipid-related genes were obtained from the Cancer Genome Atlas (TCGA) and Gene expression Omnibus (GEO) databases for differential and functional analyses. A total number of 498 patients from TCGA with complete information were included to identify a lipid-related prognostic signature (LRPS), based on ADCY2, LIPE, and OLR1, by using univariate and multivariate Cox regression analyses. LRPS-high and LRPS-low groups were accordingly divided to pathway and cell enrichment analyses.ResultsLRS-low patients had a better overall survival and relapse - free survival than LRS-high ones in HNSCC. The LRPS-high group was significantly related to perineural invasion of cancer, cancer-related pathways, high TP53 mutation rate, high proportion of natural killer T cells (NKT), dendritic cells, monocytes, Treg, and M1 and M2 macrophage infiltration in HNSCC tumor tissues. Conversely, the LRPS-low group correlated with DNA damage-related and T-cell-regulated pathways, low frequency of mutated TP53, and high infiltration of B cells and CD4+ effector cells including Th1 and Th2.ConclusionLRPS has a potential to be a promising indicator of overall survival, prognosis, TP53 status, and immune characteristics in HNSCC.

Clinical Significance of Prolymphocytes in Chinese Patients with Chronic Lymphocytic Leukemia

Introduction Chronic lymphocytic leukemia(CLL), characterized by monoclonal CD5+ B cells appearing in blood, marrow and lymphoid tissues, is the most common chronic leukemia in western countries. Until now CLL remains incurable with a heterogeneous clinical course, some patients developing progression rapidly while the others presenting a relatively indolent course. It has been reported that higher percentage of prolymphocytes was associated with increasing refractoriness to treatment and worse prognosis. In this study we were trying to explore the effect of prolymphocytes on the prognosis of CLL. Methods Two hundred and fifty-one treatment naïve CLL patients in Jiangsu Province Hospital were retrospectively enrolled in our study from April 2014 to November 2019. The median time from diagnosis to peripheral-blood smear examination was 0.13 month and median follow-up time was 30.87 months. A total of 200 lymphocytes and prolymphocytes were counted. The percentage of prolymphocytes was collected. Basic clinical characteristics and other prognostic markers including age, sex, Rai and Binet stage, B2-microglobulin(B2MG), lactate dehydrogenase(LDH) level, CD38 and ZAP70 expression level, hemoglobulin(HB), platelets count(PLT), absolute lymphocyte count(ALC), thymidine kinase-1(TK-1), albumin(ALB), IGHV mutation status and TP53 status were also put in the analysis. The time to first treatment(TTFT)was defined as the time from sampling to first treatment and the overall survival(OS) time was the time from sampling to death. An X-tile analysis provided the optimal prolymphocyte cutoff point. Wilcoxon rank sum test was used to compare the distribution of prolymphocytes percentage in different subgroups. The Kaplan-Meier method was used to construct the survival curves and the log-rank test was used to compare the difference. Multivariate analysis was conducted based on the Cox-regression model. All tests were two-sided and P<0.05 was considered to be statistically significant. Statistical analysis was performed with SPSS (version 26.0; IBM Corporation, Chicago, IL) and survival curves was drawn with GraphPad Prism (version 9.0: GraphPad Software, Inc., La Jolla, CA, USA). Results Among 252 patients, most of them were male(67.7%) and 35.9% were older than 65 years old. We found significantly different distribution of prolymphocytes percentage in patients with different B2MG, Rai stage, LDH, CD38 expression, TK1, IGHV mutation status and TP53 status(Table 1). The optimal cutoff of prolymphocytes percentage provided by X-tile analysis was 1%. Then all the patients were divided into two groups based on the prolymphocytes percentage and obvious survival difference between the two groups was shown in both TTFT(P<0.001) and OS(P=0.005)(Figure 1). Age, Rai stage, Binet stage, B2MG, LDH, ALC, ALB, IGHV mutation status and prolymphocytes percentage were further included in a multivariate analysis in which, however, prolymphocytes percentage didn't show an independent prognostic effect on TTFT(P=0.370, HR=1.209(0.798-1.833)) or OS(P=0.391, HR=1.604(0.545-4.721)). Discussion In this study we found the optimal cutoff of prolymphocytes percentage was 1% which is different with previous study(Oscier et al. 2016). That may be due to that we choose TTFT as the endpoint. Besides, about prolymphocytes percentage was not statistically significant in multivariate analysis, we guess that may be attributed to that the sample was too little or there were only Chinese patients in our cohort. In conclusion, prolymphocytes percentage has certain prognostic significance in CLL patients and we think multivariate analysis would be different after we expanded our cohort. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.

OM301, a Synthetic Polypeptide Containing the p53TA (Transactivation) Domain, Impairs Mitochondrial Activity and Survival of Myeloma Cells

INTRODUCTION: Although the treatment of patients with multiple myeloma (MM) has dramatically improved, those with high-risk characteristics, including the deletion or mutation of the master tumor suppressor gene TP53 on chromosome 17, experience limited survival. OM301 is a synthetic polypeptide containing the p53TA (transactivation) domain, which prevents p53 degradation through inhibition of MDM2. Here, we demonstrate that OM301 has strong anti-MM activity in vitro and in vivo. RESULTS: We first assessed the cytotoxic effects of OM301 in MM cell lines with varying TP53 status (TP53 wild type: MM.1S, H929; TP53 mutated/null: L363, RPMI-8226, U266, JJN3, KMS11) and found that OM301 exerts significant cytotoxic effects at a concentration of ~5 µM in all cell lines we tested, while it was minimally toxic to human peripheral blood mononuclear cells. Next, using immunocompromised NSG mice models injected with MM.1S, we determined the in vivo efficacy of OM301 in three different studies. Many potent anticancer agents, particularly of peptide origin, show prominent anti-tumor effects but fail to sustain similar effects when given intraperitoneally because of poor absorption, distribution, metabolism and excretion properties. OM301 at an intraperitoneal dose of 20 mg/kg/body weight twice a day induced significant reduction in tumor size with respect to vehicle control, suggesting the stability of OM301 without any loss of its activity (n=7, p<0.0001). Accordingly, we investigated its effect in a disseminated NSG/MM.1S model and found that it significantly increased survival (p<0.0001) (see Figure). Because OM301 was designed to simulate the p53 interaction domain with MDM2, we first determined its effect on p53-MDM2 crosstalk using a p53-MDM2 co-Immunoprecipitation (co-IP) assay and compared it with effects from Nutlin-3a, a known inhibitor of p53-MDM2. The co-IP data showed that, unlike Nutlin-3a, OM301 does not inhibit the p53-MDM2 interaction. Thus, to confirm our findings, we first overexpressed MDM2 in HeLa cells, and, using MDM2-IP and p53-MDM2 co-IP, found similar observations. Additionally, OM301 also failed to induce endogenous upregulation of genes activated by p53, such as MDM2 and p21, as opposed to results from Nutlin-3a. RNA sequencing data also showed a distinctive OM301signature, as compared to Nutlin-3a in MM cells. While treatment of Nutlin-3a induced expression of p53-activated canonical genes, OM301-treated cells showed alterations in genes involved in inflammatory responses, c-Myc regulated genes, fatty acid metabolism, glucose metabolism, and oxidative phosphorylation, among others. Next, to dissect its underlying mechanism, we dual-tagged OM301 with fluorophores at the 3' and 5' ends to study its localization and its stability in MM cells. Indeed, OM301 was found to be stable and mainly localized in the cytosol. We then modified OM301 by biotinylation of its penetratin end and first verified its cytotoxic effect in different MM cell lines, which was similar to that of native OM301. The biotinylated OM301 was then immunoprecipitated using streptavidin beads. The streptavidin pull-down and subsequent proteomic analysis confirmed that OM301 does not interact with MDM2 but interacts with c-Myc and with proteins localized in mitochondria, including Bcl-2 and Bcl-2 family members such as Bclaf1, Bcl2L13, and Bcl2L1. Pull-down experiments and immunoblot analysis validated Bcl-2/OM301 interactions. To further evaluate the relative binding potentials of OM301, we performed molecular docking studies using the HPEPDOCK server (Yan et al., Nat Protoc. 2020;15:1829). Post-docking, the calculated docking scores for OM301 was -281, suggesting that OM301directly interacts with Bcl-2. Thus, we evaluated the effects of OM301 on mitochondrial function and physiology. Treatment with OM301 decreased mitochondrial membrane potential in different MM cell lines. OM301 also increased mitochondrial superoxide production and induced mitophagy and mitochondrial fission as seen by electron microscopy. CONCLUSION: Here, we report for the first time that OM301, although designed for p53-selective cells, may instead interact with Bcl-2, which in turn induces mitochondrial dysfunction, leading to cell death irrespective of their TP53 status. Our data suggest that OM301 may be a novel and effective therapeutic option for MM. Figure 1 Figure 1. Disclosures Krishnan: REGENERON: Consultancy; MAGENTA: Consultancy; BMS: Consultancy, Current equity holder in publicly-traded company, Speakers Bureau; JANSSEN: Consultancy, Research Funding; City of Hope Cancer Center: Current Employment; SANOFI: Consultancy; GSK: Consultancy; Amgen: Speakers Bureau. Marcucci: Novartis: Other: Speaker and advisory scientific board meetings; Agios: Other: Speaker and advisory scientific board meetings; Abbvie: Other: Speaker and advisory scientific board meetings.

Association of TP53 Alteration with Tissue Specificity and Patient Outcome of IDH1-Mutant Glioma

Since the initial discovery of recurrent isocitrate dehydrogenase 1 (IDH1) mutations at Arg132 in glioma, IDH1 hotspot mutations have been identified in cholangiocarcinoma, chondrosarcoma, leukemia, and various other types of cancer of sporadic incidence. Studies in glioma and leukemia have helped promote the theory that IDH1 mutations are an oncogenic event that drives tumorigenesis in general. Through bioinformatic analysis of more than 45,000 human pan-cancer samples from three independent datasets, we show here that IDH1 mutations are rare events in human cancer but are exclusively prevalent in WHO grade II and grade III (lower-grade) glioma. Interestingly, alterations in the tumor-suppressor gene TP53 (tumor protein p53) co-occur significantly with IDH1 mutations and show a tendency of exclusivity to IDH2 mutations. The co-occurrence of IDH1 mutation and TP53 alteration is widespread in glioma, particularly in those harboring IDH1R132H, IDH1R132G, and IDH1R132S, whereas co-occurrence of IDH1R132C and TP53 alteration can be found sporadically in other cancer types. In keeping with the importance of p53 in tumor suppression, TP53 status is an independent predictor of overall survival irrespective of histological and molecular subgroups in lower-grade glioma. Together, these results indicate tissue specificity of IDH1 hotspot mutation and TP53 alteration and the importance of TP53 status as a predictor of patient outcome in lower-grade glioma.

Frequency of longitudinal changes in TP53 mutation status from gene sequencing of serial tumor biopsies from a large cohort of cancer patients.

3124 Background: The p53 pathway is one of the most important in cancer biology, with mutation of the TP53 gene that encodes the p53 tumor suppressor protein observed in ≈50% of all cancers. We evaluated the frequency of changes in TP53 mutation status in a large cohort of serial tumor biopsies. Methods: From a database of >200,000 next-generation gene sequencing results we identified 16,592 samples arising from repeat biopsies from 7840 patients (pts), average 2.12 per pt, 1007 pts with ≥3, max 11; over an interval up to 234 months (mos), average 11.0 mos. TP53 mutations with known or unknown significance in successive biopsies and changes in assignment from TP53-Wild-Type (WT) to Mutant (Mut), or Mut to WT, were evaluated vs. cancer type and time between biopsies. Results: Table: N (%) of samples vs. change in TP53 status from previous biopsy vs. mos from initial biopsy in all samples (7840 initial + 8752 successive, 46% TP53-Mut) and the three most represented cancers: non-small cell lung cancer (NSCLC, 1189 initial + 1268 successive, 60% Mut), breast (947 initial + 993 successive, 55% Mut), multiple myeloma (MM, 578 initial + 981 successive, 18% Mut). Conclusions: Changes in TP53 status were rare (<10% of samples). Differences may occur in serial biopsy samples for pathophysiological reasons, e.g., a mutant clone becoming dominant and/or heterogeneity at different tumor biopsy sites, or analytical differences in biopsy tumor content or assay sensitivity between samples. In this analysis, WT-to-Mut changes were more frequent (5.9%) than Mut-to-WT changes (3.3%), suggesting a small selection pressure for TP53 alterations later in oncogenesis and indicating that these alterations are truncal. Mut-to-WT changes are not readily explained physiologically and may suggest these infrequent changes are mostly due to sampling or analytical variability, and genuine changes in TP53 mutation status are quite rare.[Table: see text]

Differentiating TP53 Mutation Status in Pancreatic Ductal Adenocarcinoma Using Multiparametric MRI-Derived Radiomics

ObjectivesThis study assessed the preoperative prediction of TP53 status based on multiparametric magnetic resonance imaging (mpMRI) radiomics extracted from two-dimensional (2D) and 3D images.Methods57 patients with pancreatic cancer who underwent preoperative MRI were included. The diagnosis and TP53 gene test were based on resections. Of the 57 patients included 37 mutated TP53 genes and the remaining 20 had wild-type TP53 genes. Two radiologists performed manual tumour segmentation on seven different MRI image acquisition sequences per patient, including multi-phase [pre-contrast, late arterial phase (ap), portal venous phase, and delayed phase] dynamic contrast enhanced (DCE) T1-weighted imaging, T2-weighted imaging (T2WI), Diffusion-weighted imaging (DWI), and apparent diffusion coefficient (ADC). PyRadiomics-package was used to generate 558 two-dimensional (2D) and 994 three-dimensional (3D) image features. Models were constructed by support vector machine (SVM) for differentiating TP53 status and DX score method were used for feature selection. The evaluation of the model performance included area under the curve (AUC), accuracy, calibration curves, and decision curve analysis.ResultsThe 3D ADC-ap-DWI-T2WI model with 11 selected features yielded the best performance for differentiating TP53 status, with accuracy = 0.91 and AUC = 0.96. The model showed the good calibration. The decision curve analysis indicated that the radiomics model had clinical utility.ConclusionsA non-invasive and quantitative mpMRI-based radiomics model can accurately predict TP53 mutation status in pancreatic cancer patients and contribute to the precision treatment.

Clinical and Prognostic Implications of an Immune-Related Risk Model Based on TP53 Status in Lung Adenocarcinoma

Background: TP53 mutation is the most widespread mutation in lung adenocarcinoma (LUAD), meanwhile p53 (encoded by TP53) has recently been implicated in immune responses. However, it is still unknown whether TP53 mutation may remodel tumor microenvironment to influence tumor progression and prognosis in LUAD.Methods: we developed a six-gene immune-related model (IRM) to predict the survival of patients with LUAD in TCGA cohort based on TP53 status using LASSO Cox analysis, which was also confirmed the predictive ability in two independent cohorts.Results: The mutation of TP53 led to a decrease in the immune response in LUAD. Further analysis revealed that patients in the high-index group had observably lower relative infiltration of memory B cells and regulatory T cells, together with significantly higher relative infiltration proportions neutrophils and resting memory CD4+ T cells. Additionally, the IRM index positively correlated with expression of critical immune checkpoint genes including PDCD1 (encoding PD-1) and CD274 (encoding PD-L1), which was validated in Nanjing cohort. Furthermore, the IRM index as an independent prognostic factor was used to establish a nomogram for clinical application.Conclusion: This immune-related model may serve as a powerful prognostic tool to further optimize immunotherapies for LUAD.