pubmed > TP53 > tumor protein 53

Clinicopathological and Immunohistochemical Profile of Mantle Cell Lymphoma: An Institutional Experience.
Introduction Mantle cell lymphoma (MCL) is a biologically aggressive B-cell non-Hodgkin lymphoma (NHL) with distinctive morphologic, immunophenotypic, and molecular characteristics. Differentiation from other chronic lymphoproliferative disorders is essential for prognostication. Aim This paper aims to study the clinicopathological features of MCL with emphasis on immunohistochemical features and disease correlation. Method To do so, clinicopathological characteristics from 21 cases of MCL (14 males, seven females, M:F=2:1) diagnosed in the last five years i.e. 2015 to 2020, were retrospectively reviewed and correlated with immunohistochemistry (IHC) data. Particularly those pertaining to cyclin D1, SRY-box transcription factor 11 (SOX11), cluster of differentiation (CD) 5, CD23, MIB E3 ubiquitin protein ligase 1 (MIB1), tumor protein 53 (TP53), c-myelocytomatosis oncogene product (c-MYC), multiple myeloma oncogene 1 (MUM1), mouse double minute 2 homolog (MDM2), and Epstein-Barr virus latent membrane protein 1 (EBV-LMP1) expression with its aberrations. Observations This study shows that MCL constituted 4.2% (21/500) of all NHLs with a mean age of 57.5 years (median 60 years, range 30 to 80 years). The disease was nodal in 19, and extranodal in the remaining two cases. 14 of 21 (67%) had generalized lymphadenopathy and 71% had bone marrow (BM) involvement. The nodal involvement was diffuse in 9/17 (53%), 8/21 (38%) had a blastoid morphology, and an in-situ MCL pattern was not seen in any of the cases selected for the study. Cyclin D1 immunoexpression correlated well with SOX11; CD5-negative in five cases; and CD23-positive in three cases. TP53 and c-MYC expression were noted in 17/19 (89.4%) and 8/17 (47%), respectively. MUM1 registered positive in six cases. None of the cases showed immunopositivity for MDM2 and EBV-LMP1. Conclusion In essence, this study indicates that morphological and immunophenotypic subclassification of mantle cell lymphoma with a wider panel of IHC markers is essential for understanding disease biology and better prognostication.
Publication Date: 2021-08-26
Journal: Cureus

The association between the expression of nuclear Yes-associated protein 1 (YAP1) and p53 protein expression profile in breast cancer patients.
Yes-associated protein 1 (YAP1) is a key effector molecule regulated by the Hippo pathway and described as a poor prognostic factor in breast cancer. Tumor protein 53 (TP53) mutation is well known as a biomarker related to poor survival outcomes. So far clinical characteristics and survival outcome according to YAP1 and TP53 mutation have been poorly identified in breast cancer. Retrospectively, 533 breast tumor tissues were collected at the Seoul St Mary's hospital and Gangnam Severance Hospital from 1992 to 2017. Immunohistochemistry with YAP1 and p53 specific antibodies were performed, and the clinical data were analyzed. Mutant p53 pattern was associated with aggressive tumor features and advanced anatomical stage. Inferior overall survival (OS) and recurrence free survival (RFS) were related with mutant p53 pattern cases with low nuclear YAP1 expression (P = 0.0009 and P = 0.0011, respectively). Multivariate analysis showed that mutant p53 pattern was an independent prognostic marker for OS [hazard ratios (HR): 2.938, 95% confidence intervals (CIs): 1.028-8.395, P = 0.044] and RFS (HR: 1.842, 95% CIs: 1.026-3.304). However, in cases with high nuclear YAP1 expression, there were no significantly difference in OS and RFS according to p53 staining pattern. We found that mutant p53 pattern is a poor prognostic biomarker in breast tumor with low nuclear YAP1 expression. Our findings suggest that interaction between nuclear YAP1 and p53 expression pattern impact survival outcomes.
Publication Date: 2021-05-11
Journal: PloS one

Dedifferentiated Mesonephric-like Adenocarcinoma of the Uterine Corpus.
We present a case of uterine dedifferentiated mesonephric-like adenocarcinoma (MLA). A 54-year-old woman underwent total hysterectomy for a uterine mass under the impression of a uterine sarcoma. Histologically, MLA exhibited various growth patterns including tubular and glandular architecture. Undifferentiated carcinoma (UC) displayed discohesive tumor cells without any obvious architecture. Immunohistochemically, UC was positive for epithelial markers in very few scattered tumor cells. MLA exhibited the wild-type p53 expression pattern, whereas UC showed a uniform and strong p53 immunoreactivity. Targeted sequencing analysis revealed an identical Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation in both components. A pathogenic missense tumor protein 53 (TP53) mutation was detected in UC, but not in MLA. The mutant p53 expression pattern exclusively detected in UC was concordant with the presence of missense TP53 mutation. Our observations suggested that TP53 mutation is associated with the possible transformation from MLA to UC.
Publication Date: 2021-05-07
Journal: Anticancer research

DNA repair pathways and their roles in drug resistance for lung adenocarcinoma.
Lung cancer is the leading cancer type of death rate. The lung adenocarcinoma subtype is responsible for almost half of the total lung cancer deaths. Despite the improvements in cancer treatment in recent years, lung adenocarcinoma patients' overall survival rate remains poor. Immunetherapy and chemotherapy are two of the most widely used options for the treatment of cancer. Although many cancer types initially respond to these treatments, the development of resistance is inevitable. The rapid development of drug resistance mainly characterizes lung adenocarcinoma. Despite being the subject of many studies in recent years, the resistance initiation and progression mechanism is still unclear. In this review, we have examined the role of the primary DNA repair pathways (non-homologous end joining (NHEJ) pathway, homologous-recombinant repair (HR) pathway, base excision repair (BER) pathway, and nucleotide excision repair (NER) pathway and transactivation mechanisms of tumor protein 53 (TP53) in drug resistance development. This review suggests that mentioned pathways have essential roles in developing the resistance against chemotherapy and immunotherapy in lung adenocarcinoma patients.
Publication Date: 2021-04-16
Journal: Molecular biology reports

Acinic Cell Carcinoma of the Breast: Report of a Case With Immunohistochemical and Next-Generation Sequencing Studies.
Acinic cell carcinoma of the breast is a rare subtype of triple-negative breast cancer that recapitulates the appearance of tumors seen in salivary glands. We present the case of a 42-year-old woman with an irregular, nontender mass above the left nipple during routine obstetric appointment at 24 weeks gestation. She was subsequently diagnosed with triple-negative invasive ductal carcinoma of the left breast, Nottingham grade 3, via core needle biopsy. She was treated with neoadjuvant therapy (doxorubucin and cyclophosphamide) antenatally and paclitaxel in the postpartum period followed by left mastectomy with sentinel node biopsy. The carcinoma in the mastectomy specimen showed a spectrum of morphologic patterns with immunohistochemistry revealing strong positivity for alpha-1-antichymotrypsin, epithelial membrane antigen (EMA), lysozyme, and S100. The histomorphology paired with the immunoprofile led us to the diagnosis of acinic cell carcinoma. We retrospectively performed immunostains in the core biopsy specimen, which demonstrated GATA-3 and DOG-1 positivity. Next-generation sequencing of the postneoadjuvant specimen using a 70-gene panel revealed 2 single-nucleotide variant (SNV) mutations: tumor protein 53 (TP53) (c.747G>T) SNV mutation and rearranged during transfection (RET) (c.2899G>A) SNV mutation.
Publication Date: 2021-04-09
Journal: International journal of surgical pathology

Transcriptomic signaling pathways involved in a naturalistic model of inflammation-related depression and its remission.
This study aimed at identifying molecular biomarkers of inflammation-related depression in order to improve diagnosis and treatment. For this, we performed whole-genome expression profiling from peripheral blood in a naturalistic model of inflammation-associated major depressive disorder (MDD) represented by comorbid depression in obese patients. We took advantage of the marked reduction of depressive symptoms and inflammation following bariatric surgery to test the robustness of the identified biomarkers. Depression was assessed during a clinical interview using Mini-International Neuropsychiatric Interview and the 10-item, clinician-administered, Montgomery-Asberg Depression Rating Scale. From a cohort of 100 massively obese patients, we selected 33 of them for transcriptomic analysis. Twenty-four of them were again analyzed 4-12 months after bariatric surgery. We conducted differential gene expression analyses before and after surgery in unmedicated MDD and non-depressed obese subjects. We found that TP53 (Tumor Protein 53), GR (Glucocorticoid Receptor), and NFκB (Nuclear Factor kappa B) pathways were the most discriminating pathways associated with inflammation-related MDD. These signaling pathways were processed in composite z-scores of gene expression that were used as biomarkers in regression analyses. Results showed that these transcriptomic biomarkers highly predicted depressive symptom intensity at baseline and their remission after bariatric surgery. While inflammation was present in all patients, GR signaling over-activation was found only in depressed ones where it may further increase inflammatory and apoptosis pathways. In conclusion, using an original model of inflammation-related depression and its remission without antidepressants, we provide molecular predictors of inflammation-related MDD and new insights in the molecular pathways involved.
Publication Date: 2021-04-08
Journal: Translational psychiatry

Protein-Protein Interaction Analysis through Network Topology (Oral Cancer).
Oral cancer is a complex disorder. Its creation and spreading are due to the interaction of several proteins and genes in different biological thoroughfares. To study biological pathways, many high-yield methods have been used. Efforts to merge several data found at separate levels related to biological thoroughfares and interlinkage networks remain elusive. In our research work, we have proposed a technique known as protein-protein interaction network for analysis and exploring the genes involved in oral cancer disorders. The previous studies have not fully analyzed the proteins or genes involved in oral cancer. Our proposed technique is fully interactive and analyzes the data of oral cancer disorder more accurately and efficiently. The methods used here enabled us to observe the wide network consists of one mighty network comprising of 208 nodes 1572 edges which connect these nodes and various detached small networks. In our study, TP53 is a gene that occupied an important position in the network. TP53 has a 113-degree value and 0.03881821 BC value, indicating that TP53 is centrally localized in the network and is a significant bottleneck protein in the oral cancer protein-protein interaction network. These findings suggested that the pathogenesis of oral cancer variation was organized by means of an integrated PPI network, which is centered on TP53. Furthermore, our identification shows that TP53 is the key role-playing protein in the oral cancer network, and its significance in the cellular networks in the body is determined as well. As TP53 (tumor protein 53) is a vital player in the cell division process, the cells may not grow or divide disorderly; it fulfills the function of at least one of the gene groups in oral cancer. However, the latter progression in the area is any measure; the intention of developing these networks is to transfigure sketch of core disease development, prognosis, and treatment.
Publication Date: 2021-01-30
Journal: Journal of healthcare engineering

Host-Viral Interactions Revealed among Shared Transcriptomics Signatures of ARDS and Thrombosis: A Clue into COVID-19 Pathogenesis.
Severe novel corona virus disease 2019 (COVID-19) infection is associated with a considerable activation of coagulation pathways, endothelial damage, and subsequent thrombotic microvascular injuries. These consistent observations may have serious implications for the treatment and management of this highly pathogenic disease. As a consequence, the anticoagulant therapeutic strategies, such as low molecular weight heparin, have shown some encouraging results. Cytokine burst leading to sepsis which is one of the primary reasons for acute respiratory distress syndrome (ARDS) drive that could be worsened with the accumulation of coagulation factors in the lungs of COVID-19 patients. However, the obscurity of this syndrome remains a hurdle in making decisive treatment choices. Therefore, an attempt to characterize shared biological mechanisms between ARDS and thrombosis using comprehensive transcriptomics meta-analysis is made. We conducted an integrated gene expression meta-analysis of two independently publicly available datasets of ARDS and venous thromboembolism (VTE). Datasets GSE76293 and GSE19151 derived from National Centre for Biotechnology Information-Gene Expression Omnibus (NCBI-GEO) database were used for ARDS and VTE, respectively. Integrative meta-analysis of expression data (INMEX) tool preprocessed the datasets and effect size combination with random effect modeling was used for obtaining differentially expressed genes (DEGs). Network construction was done for hub genes and pathway enrichment analysis. Our meta-analysis identified a total of 1,878 significant DEGs among the datasets, which when subjected to enrichment analysis suggested inflammation-coagulation-hypoxemia convolutions in COVID-19 pathogenesis. The top hub genes of our study such as tumor protein 53 (TP53), lysine acetyltransferase 2B (KAT2B), DExH-box helicase 9 (DHX9), REL-associated protein (RELA), RING-box protein 1 (RBX1), and proteasome 20S subunit beta 2 (PSMB2) gave insights into the genes known to be participating in the host-virus interactions that could pave the way to understand the various strategies deployed by the virus to improve its replication and spreading.
Publication Date: 2020-12-24
Journal: TH open : companion journal to thrombosis and haemostasis

Transcriptomic analysis of tobacco-flavored E-cigarette and menthol-flavored E-cigarette exposure in the human middle ear.
Electronic cigarettes (e-cigarettes) are the most widely used electronic nicotine delivery systems and are designed to imitate smoking and aid in smoking cessation. Although the number of e-cigarette users is increasing rapidly, especially among young adults and adolescents, the potential health impacts and biologic effects of e-cigarettes still need to be elucidated. Our previous study demonstrated the cytotoxic effects of electronic liquids (e-liquids) in a human middle ear epithelial cell (HMEEC-1) line, which were affected by the manufacturer and flavoring agents regardless of the presence of nicotine. In this study, we aimed to evaluate the gene expression profile and identify potential molecular modulator genes and pathways in HMEEC-1 exposed to two different e-liquids (tobacco- and menthol-flavored). HMEEC-1 was exposed to e-liquids, and RNA sequencing, functional analysis, and pathway analysis were conducted to identify the resultant transcriptomic changes. A total of 843 genes were differentially expressed following exposure to the tobacco-flavored e-liquid, among which 262 genes were upregulated and 581 were downregulated. Upon exposure to the menthol-flavored e-liquid, a total of 589 genes were differentially expressed, among which 228 genes were upregulated and 361 were downregulated. Among the signaling pathways associated with the differentially expressed genes mediated by tobacco-flavored e-liquid exposure, several key molecular genes were identified, including IL6 (interleukin 6), PTGS2 (prostaglandin-endoperoxide synthase 2), CXCL8 (C-X-C motif chemokine ligand 8), JUN (Jun proto-oncogene), FOS (Fos proto-oncogene), and TP53 (tumor protein 53). Under menthol-flavored e-liquid treatment, MMP9 (matrix metallopeptidase 9), PTGS2 (prostaglandin-endoperoxide synthase 2), MYC (MYC proto-oncogene, bHLH transcription factor), HMOX1 (heme oxygenase 1), NOS3 (nitric oxide synthase 3), and CAV1 (caveolin 1) were predicted as key genes. In addition, we identified related cellular processes, including inflammatory responses, oxidative stress and carcinogenesis, under exposure to tobacco- and menthol-flavored e-liquids. We identified differentially expressed genes and related cellular processes and gene signaling pathways after e-cigarette exposure in human middle ear cells. These findings may provide useful evidence for understanding the effect of e-cigarette exposure.
Publication Date: 2020-11-29
Journal: Scientific reports

Comprehensive bioinformatics analysis of the TP53 signaling pathway in Wilms' tumor.
Differential expression of tumor protein 53 (TP53, or p53) has been observed in multiple cancers. However, the expression levels and prognostic role of TP53 signaling pathway genes in Wilms' tumor (WT) have yet to be fully explored. The expression levels of TP53 signaling pathway genes including TP53, mouse double minute 2 (MDM2), mouse double minute 4 (MDM4), cyclin-dependent kinase 2A (CDKN2A), cyclin-dependent kinase 2B (CDKN2B), and tumor suppressor p53-binding protein 1 (TP53BP1) in WT were analyzed using the Oncomine database. Aberration types, co-mutations, mutation locations, signaling pathways, and the prognostic role of TP53 in WT were investigated using cBioPortal. MicroRNA (miRNA) and transcription factor (TF) targets were identified with miRTarBase, miWalk, and ChIP-X Enrichment Analysis 3 (CheA3), respectively. A protein-protein network was constructed using GeneMANIA. The expression of TP53 signaling genes were confirmed in WT samples and normal kidney tissues using the Human Protein Atlas (HPA). Cancer Therapeutics Response Portal (CTRP) was used to analyze the small molecules potentially targeting TP53. TP53 was significantly expressed in the Cutcliffe Renal (P=0.010), but not in the Yusenko Renal (P=0.094). Meanwhile, MDM2 was significantly overexpressed in the Yusenko Renal (P=0.058), but not in the Cutcliffe Renal (P=0.058). The expression levels of MDM4 no significant difference between the tumor and normal tissue samples. The most common TP53 alteration was missense and the proportion of TP53 pathway-related mutations was 2.3%. Co-expressed genes included ZNF609 (zinc finger protein 609), WRAP53 (WD40-encoding RNA antisense to p53), CNOT2 (CC chemokine receptor 4-negative regulator of transcription 2), and CDH13 (cadherin 13). TP53 alterations indicated poor prognosis of WT (P=1.051e-4). The regulators of the TP53 pathway included miR-485-5p and TFs NR2F2 and KDM5B. The functions of TP53 signaling pathway were signal transduction in response to DNA damage and regulate the cell cycle. The small molecules targeting TP53 included PRIMA-1, RITA, SJ-172550, and SCH-529074. TP53 was found to be differentially expressed in WT tissues. TP53 mutations indicated poor outcomes of WT. Therefore, pifithrin-mu, PRIMA-1, RITA, SJ-172550, and SCH-529074 could be used in combination with traditional chemotherapy to treat WT.
Publication Date: 2020-11-13
Journal: Annals of translational medicine

Extracellular vesicles enriched with miR-150 released by macrophages regulates the TP53-IGF-1 axis to alleviate myocardial infarction.
Myocardial infarction (MI) is recognized as a major cause of death and disability around the world. Macrophage-derived extracellular vesicles (EVs) have been reportedly involved in the regulation of cellular responses to MI. Thus, we sought to clarify the mechanism by which macrophage-derived EVs regulate this process. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was performed to determine microRNA-150 (miR-150) expression in an MI mouse model with ligation of the left anterior descending coronary artery (LAD) and in hypoxia/reoxygenation (H/R)-exposed cardiomyocytes. Bioinformatics analysis and dual luciferase reporter gene assay were adopted to identify the correlation of miR-150 with tumor protein 53 (TP53) expression in cardiomyocytes. Gain- and loss-of-function experiments were conducted in H/R-induced cardiomyocytes, cardiomyocytes incubated with EVs from miR-150 mimic-transfected macrophages, or MI-model mice treated with EVs from miR-150 mimic-transfected macrophages. hematoxylin-eosin (HE) and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) staining assays were used for detecting inflammatory infiltration and cell apoptosis. The release of lactate dehydrogenase (LDH) by dead cardiomyocytes was measured with an LDH kit, and the apoptosis-related proteins, Bax, and cleaved-caspase 3 were determined by Western blot analysis. miR-150 expression was downregulated in the infarcted cardiac tissues of MI mice. Macrophage-derived EVs could transfer miR-150 into cardiomyocytes, where it directly targeted and suppressed TP53. Furthermore, miR-150 suppressed phosphatase and tensin homology (PTEN) and activated p-Akt to upregulate IGF-1 expression. Furthermore, increased expression of EV-derived miR-150 prevented cardiomyocyte apoptosis in vitro, as evidenced by downregulated Bax and cleaved-caspase 3 and upregulated Bcl2 and alleviated MI in vivo. In conclusion, our study demonstrates the cardioprotective effect of macrophage-derived EV-miR-150 on MI-induced heart injury through negatively regulating the TP53-IGF-1 signaling pathway.
Publication Date: 2020-11-10
Journal: American journal of physiology. Heart and circulatory physiology

Metastatic colon cancer of the small intestine diagnosed using genetic analysis: a case report.
Intestinal-type adenocarcinoma is widely detected in the gastrointestinal tract, head and neck, lower respiratory and urinary systems. Determining the nature (monoclonal or multicentric) of the intestinal adenocarcinoma is sometimes a diagnostic challenge owing to its occurrence at various locations of the body, especially in the lower gastrointestinal tract. Herein, we successfully diagnosed metastatic colon cancer in the small intestine using tumor protein 53 gene (TP53) mutation analysis. An 83-year-old woman presented with severe abdominal pain and nausea at the emergency department of the hospital. Her history included surgery and adjuvant chemotherapy for colon and breast cancers. Abdominal computed tomography revealed small intestinal dilation, which was associated with the mural nodule detected on fluorodeoxyglucose positron emission tomography. Laparoscopy-assisted small bowel resection was performed based on the diagnosis of small bowel obstruction, probably due to recurrence of the colon or breast cancer. Macroscopically, an ulcerated tumor was present in the resected small intestine. Histologically, the cancer cells showed infiltrative growth of colonic dysplastic glands, whose non-specific finding made it difficult to determine the relationship with past colon cancers. Retrospective pathological examination confirmed that the previous breast and colon carcinomas were primary cancers. Immunohistochemical analysis revealed that the small intestinal and colon cancer cells showed diffuse positive tumor protein 53 (p53) expression. However, the breast cancer cells showed only weakly positive p53 expression. In addition, TP53 mutational analysis detected an identical missense mutation (p.T211I) between the two intestinal cancers. Moreover, further molecular genetic work-up revealed that both small intestinal and colon adenocarcinomas harbored an identical missense mutation (p.G12D) of KRAS gene. In conclusion, the small intestinal cancer in this case was identified as a metastatic adenocarcinoma arising from a past colon cancer. Genetic analyses help in clarifying the identity of the cells in multiple cancer cases. In morphologically indeterminate cases, molecular analysis of common cancer-related genes can be useful for a precise and reproducible diagnosis.
Publication Date: 2020-09-02
Journal: Diagnostic pathology

A Network Pharmacology Approach to Explore the Mechanisms of Shugan Jianpi Formula in Liver Fibrosis.
We explored the mechanism of Shugan Jianpi Formula (SGJPF) and its effective components for the treatment of liver fibrosis (LF). We collected the active ingredients in SGJPF through the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform and screened the effective components by absorption, distribution, metabolism, and excretion. Herb-associated target proteins were predicted and screened based on the Bioinformatics Analysis Tool for Molecular Mechanism of Traditional Chinese Medicine and Search Tool for Interactions of Chemicals databases. LF-associated target proteins were predicted and screened based on the Online Mendelian Inheritance in Man® Database and Comparative Toxicogenomics Database. Common genes with LF and herbs were selected, and Cytoscape 3.5.1 software was used to construct an herb pathway and component-LF common target network. The Search Tool for the Retrieval of Interacting Genes/Proteins was used to build a protein-protein interaction, and quantitative PCR was used to verify the related target genes. Finally, clusterProfiler was applied for the analysis of Gene Ontology terms and Kyoto Encyclopedia of Genes and Genomes pathways. The pharmacological network contained 252 active compounds (e.g., Astragaloside A, saikosaponin, linoleic acid, and Poria acid A), 84 common target genes, and 94 significant signaling pathways. Among them, interleukin 6 (IL-6), tumor protein 53 p53 (TP53), prostaglandin-endoperoxide synthase 2 (PTGS2), AKT1, IL-1 The mechanisms of SGJPF in protecting against LF include the regulation of multiple targets such as IL-6, TP53, PTGS2, and AKT1. These target proteins affect LF through various signal transduction pathways.
Publication Date: 2020-07-04
Journal: Evidence-based complementary and alternative medicine : eCAM

The Killing of Human Neuroblastoma Cells by the Small Molecule JQ1 Occurs in a p53-Dependent Manner.
MYCN amplification is a prognostic biomarker associated with poor prognosis of neuroblastoma in children. The overall survival of children with MYCN-amplified neuroblastoma has only marginally improved within the last 20 years. The Bromodomain and Extra-Terminal motif (BET) inhibitor, JQ1, has been shown to downregulate MYCN in neuroblastoma cells. To determine if JQ1 downregulation of MYCN in neuroblastomas can offer a target- specific therapy for this, difficult to treat, pediatric cancer. Since MYCN-amplified neuroblastoma accounts for as much as 40 to 50 percent of all high-risk cases, we compared the effect of JQ1 on both MYCN-amplified and non-MYCN-amplified neuroblastoma cell lines and investigated its mechanism of action. In this study, we show that JQ1 can specifically target MYCN for downregulation, though this effect is not specific to only MYCN-amplified cells. And although we can confirm that the loss of MYCN alone can induce apoptosis, the exogenous rescue of MYCN expression can abrogate much of this cytotoxicity. More fascinating, however, was the discovery that the JQ1-induced knockdown of MYCN, which led to the loss of the human double minute 2 homolog (HDM2) protein, also led to the accumulation of tumor protein 53 (also known as TP53 or p53), which ultimately induced apoptosis. Likewise, the knockdown of p53 also blunted the cytotoxic effects of JQ1. These data suggest a mechanism of action for JQ1 cytotoxicity in neuroblastomas and offer a possible prognostic target for determining its efficacy as a therapeutic.
Publication Date: 2020-04-25
Journal: Anti-cancer agents in medicinal chemistry

Implications of driver genes associated with a high tumor mutation burden identified using next-generation sequencing on immunotherapy in hepatocellular carcinoma.
Immune checkpoint blockade (ICB) therapy is a treatment strategy for hepatocellular carcinoma (HCC); however, its clinical efficacy is limited to a select subset of patients. Next-generation sequencing has identified the value of tumor mutation burden (TMB) as a predictor for ICB efficacy in multiple types of tumor, including HCC. Specific driver gene mutations may be indicative of a high TMB (TMB-H) and analysis of such mutations may provide novel insights into the underlying mechanisms of TMB-H and potential therapeutic strategies. In the present study, a hybridization-capture method was used to target 1.45 Mb of the genomic sequence (coding sequence, 1 Mb), analyzing the somatic mutation landscape of 81 HCC tumor samples. Mutations in five genes were significantly associated with TMB-H, including mutations in tumor protein 53 (TP53), Catenin
Publication Date: 2020-03-29
Journal: Oncology letters

Pathologic complete response to preoperative immunotherapy in a lung adenocarcinoma patient with bone metastasis: A case report.
Anti-programmed cell death 1 (PD-1) and its ligand (PD-L1) has emerged as a novel immunotherapy for non-small cell lung cancer (NSCLC). However, the proportion of patients who may benefit from immunotherapy is limited and the factors sensitive or resistant to immunotherapy are not completely clear. Therefore, to identify reliable biomarkers as predictors of clinical response and resistance to anti-PD-1/PD-L1 therapies have become increasingly important. Here, we report a case of a patient with bone metastatic NSCLC, who achieved a pathologic complete response after preoperative pembrolizumab treatment. Postoperative pathological examination found no viable cancer cells in the resected pulmonary nodules and lymph nodes. Several high-frequency DNA damage response and repair (DDR) gene mutations including two germline mutations were identified in the primary lesion. Moreover, high PD-L1 expression, Kirsten rat sarcoma viral oncogene homolog (KRAS) combined with tumor protein 53 (TP53) mutations without epidermal growth factor receptor (EGFR)/anaplastic lymphoma kinase (ALK) driver alterations, high infiltration level of CD8-positive cells and M1 macrophages were observed, which were favorable characteristics for immunotherapy. We explored the possible factors related to an excellent response to immune checkpoint inhibitor in this patient and determined that preoperative use of anti-PD-1 therapy might apply to late-stage lung adenocarcinoma patients with multidimensional advantageous biomarkers for treatment with immune checkpoint inhibitors (ICIs). KEY POINTS: We characterized the genomic features and immune microenvironment signature of a lung adenocarcinoma in a patient with bone metastasis who achieved pathologic complete response after pembrolizumab treatment. To evaluate multidimensional advantageous biomarkers for immunotherapy.
Publication Date: 2020-02-23
Journal: Thoracic cancer

Easy One-Step Amplification and Labeling Procedure for Copy Number Variation Detection.
The specific characteristics of copy number variations (CNVs) require specific methods of detection and characterization. We developed the Easy One-Step Amplification and Labeling procedure for CNV detection (EOSAL-CNV), a new method based on proportional amplification and labeling of amplicons in 1 PCR. We used tailed primers for specific amplification and a pair of labeling probes (only 1 labeled) for amplification and labeling of all amplicons in just 1 reaction. Products were loaded directly onto a capillary DNA sequencer for fragment sizing and quantification. Data obtained could be analyzed by Microsoft Excel spreadsheet or EOSAL-CNV analysis software. We developed the protocol using the LDLR (low density lipoprotein receptor) gene including 23 samples with 8 different CNVs. After optimizing the protocol, it was used for genes in the following multiplexes: BRCA1 (BRCA1 DNA repair associated), BRCA2 (BRCA2 DNA repair associated), CHEK2 (checkpoint kinase 2), MLH1 (mutL homolog 1) plus MSH6 (mutS homolog 6), MSH2 (mutS homolog 2) plus EPCAM (epithelial cell adhesion molecule) and chromosome 17 (especially the TP53 [tumor protein 53] gene). We compared our procedure with multiplex ligation-dependent probe amplification (MLPA). The simple procedure for CNV detection required 150 min, with <10 min of handwork. After analyzing >240 samples, EOSAL-CNV excluded the presence of CNVs in all controls, and in all cases, results were identical using MLPA and EOSAL-CNV. Analysis of the 17p region in tumor samples showed 100% similarity between fluorescent in situ hybridization and EOSAL-CNV. EOSAL-CNV allowed reliable, fast, easy detection and characterization of CNVs. It provides an alternative to targeted analysis methods such as MLPA.
Publication Date: 2020-02-19
Journal: Clinical chemistry

Germline cancer predisposition variants and pediatric glioma: a population-based study in California.
Pediatric astrocytoma constitutes a majority of malignant pediatric brain tumors. Previous studies that investigated pediatric cancer predisposition have primarily been conducted in tertiary referral centers and focused on cancer predisposition genes. In this study, we investigated the contribution of rare germline variants to risk of malignant pediatric astrocytoma on a population level. DNA samples were extracted from neonatal dried bloodspots from 280 pediatric astrocytoma patients (predominantly high grade) born and diagnosed in California and were subjected to whole-exome sequencing. Sequencing data were analyzed using agnostic exome-wide gene-burden testing and variant identification for putatively pathogenic variants in 175 a priori candidate cancer-predisposition genes. We identified 33 putatively pathogenic germline variants among 31 patients (11.1%) which were located in 24 genes largely involved in DNA repair and cell cycle control. Patients with pediatric glioblastoma were most likely to harbor putatively pathogenic germline variants (14.3%, N = 9/63). Five variants were located in tumor protein 53 (TP53), of which 4 were identified among patients with glioblastoma (6.3%, N = 4/63). The next most frequently mutated gene was neurofibromatosis 1 (NF1), in which putatively pathogenic variants were identified in 4 patients with astrocytoma not otherwise specified. Gene-burden testing also revealed that putatively pathogenic variants in TP53 were significantly associated with pediatric glioblastoma on an exome-wide level (odds ratio, 32.8, P = 8.04 × 10-7). A considerable fraction of pediatric glioma patients, especially those of higher grade, harbor a putatively pathogenic variant in a cancer predisposition gene. Some of these variants may be clinically actionable or may warrant genetic counseling.
Publication Date: 2020-01-24
Journal: Neuro-oncology

Current Prospects of Molecular Therapeutics in Head and Neck Squamous Cell Carcinoma.
Head and neck squamous cell carcinoma (HNSCC) has an estimated annual global death rate of approximately 300,000. Despite advances in surgical techniques, the advent of efficient radiation delivery methods, and the introduction of newer chemotherapeutic agents, the survival rate for HNSCC has alarmingly remained unchanged for the past 50 years. However, there have been some promising developments in this field recently. Tumor protein 53 (TP53)-based gene therapeutics such as Gendicine
Publication Date: 2020-01-15
Journal: Pharmaceutical medicine

Tumor protein 53 mutations in acute myeloid leukemia: conventional induction chemotherapy or novel therapeutics.
Tumor protein 53 (TP53) protein is involved in fundamental processes of cancer, aging, and DNA repair. Thus, TP53 dysfunction is implicated in malignant processes and remains the most commonly mutated gene in cancer but represents a relatively small proportion in acute myeloid leukemia (AML). Patients with TP53-mutated AML attain inferior responses to therapy resulting in poor overall outcomes. Traditional treatment approaches with conventional chemotherapy yields suboptimal responses for patients with TP53 mutant AML compared with wildtype TP53. In recent years, there is increasing interest in understanding the role and underlying biology of TP53 mutations in AML with efforts to harness the physiological tumor suppressive function of TP53 protein. Novel combination and targeted therapies may contribute to improved outcomes; however, responses to therapy may be short-lived and ongoing research is indicated to evaluate relapse-risk reduction strategies. These patients may benefit from consideration of enrollment in clinical trials or lower intensity therapy approaches in lieu of intensive chemotherapy. Pharmacological treatments targeting the TP53 pathway in addition to novel emerging therapeutics and immunotherapy-based approaches hold promise for treatment of TP53 mutant AML.
Publication Date: 2020-01-11
Journal: Current opinion in hematology