TP53 Expression Research Articles

Blocking of EGFR Signaling Is a Latent Strategy for the Improvement of Prognosis of HPV-Induced Cancer.

Human papillomavirus (HPV) is a double-stranded DNA (dsDNA) virus, and its high-risk subtypes increase cancer risks. However, the mechanism of HPV infection and pathogenesis still remain unclear. Therefore, understanding the molecular mechanisms and the pathogenesis of HPV are crucial in the prevention of HPV-related cancers. In this study, we analyzed cervix squamous cell carcinoma (CESC) and head and neck carcinoma (HNSC) combined data to investigate various HPV-induced cancer common features. We showed that epidermal growth factor receptor (EGFR) was downregulated in HPV-positive (HPV+) cancer, and that HPV+ cancer patients exhibited better prognosis than HPV-negative (HPV−) cancer patients. Our study also showed that TP53 mutation rate is lower in HPV+ cancer than in HPV− cancer and that TP53 can be modulated by HPV E7 protein. However, there was no significant difference in the expression of wildtype TP53 in both groups. Subsequently, we constructed HPV-human interaction network and found that EGFR is a critical factor. From the network, we also noticed that EGFR is regulated by HPV E7 protein and hsa-miR-944. Moreover, while phosphorylated EGFR is associated with a worse prognosis, EGFR total express level is not significantly correlated with prognosis. This indicates that EGFR activation will induce a worse outcome in HPV+ cancer patients. Further enrichment analysis showed that EGFR downstream pathway and cancer relative pathway are diversely activated in HPV+ cancer and HPV− cancer. In summary, HPV E7 protein downregulates EGFR that downregulates phosphorylated EGFR and inhibit EGFR-related pathways which in turn and consequently induce better prognosis.

CMTM3 suppresses chordoma progress through EGFR/STAT3 regulated EMT and TP53 signaling pathway

BackgroundChordomas are rare, slow-growing and locally aggressive bone sarcomas. At present, chordomas are difficult to manage due to their high recurrence rate, metastasis tendency and poor prognosis. The underlying mechanisms of chordoma tumorigenesis and progression urgently need to be explored to find the effective therapeutic targets. Our previous data demonstrates that EGFR plays important roles in chordoma development and CKLF-like MARVEL transmembrane domain containing (CMTM)3 suppresses gastric cancer metastasis by inhibiting the EGFR/STAT3/EMT signaling pathway. However, the roles and mechanism of CMTM3 in chordomas remain unknown.MethodsPrimary chordoma tissues and the paired adjacent non-tumor tissues were collected to examine the expression of CMTM3 by western blot. The expression of CMTM3 in chordoma cell lines was tested by Real-time PCR and western blot. CCK-8 and colony forming unit assay were performed to delineate the roles of CMTM3 in cell proliferation. Wound healing and Transwell assays were performed to assess cell migration and invasion abilities. A xenograft model in NSG mice was used to elucidate the function of CMTM3 in vivo. Signaling pathways were analyzed by western blot and IHC. RNA-seq was performed to further explore the mechanism regulated by CMTM3 in chordoma cells.ResultsCMTM3 expression was downregulated in chordoma tissues compared with paired normal tissues. CMTM3 suppressed proliferation, migration and invasion of chordoma cells in vitro and inhibited tumor growth in vivo. CMTM3 accelerated EGFR degradation, suppressed EGFR/STAT3/EMT signaling pathway, upregulated TP53 expression and enriched the TP53 signaling pathway in chordoma cells.ConclusionsCMTM3 inhibited tumorigenesis and development of chordomas through activating the TP53 signaling pathway and suppressing the EGFR/STAT3 signaling pathway, which suppressed EMT progression. CMTM3 might be a potential therapeutic target for chordomas.

Silencing the epitranscriptomic writer METTL3 in Hepatocellular carcinoma cells: A prospective therapeutic approach

N6-methyladenosine (m6A) is a pervasive post-transcriptional modification and has been considered a hotspot issue in the last decade. METTL3 is the major RNA methyltransferase implicated in m6A modification. Limited studies have addressed the pathologic implications of m6A dysregulation in cancer. Our aim was to target METTL3 in HepG2 cell lines by siRNA (small interfering RNA), and then evaluate the effect of this interference on HepG2 cells viability and proliferative activity. Furthermore, the functional impact of METTL3 knockdown was considered by measuring the relative expression of m6A target genes (TP53, eEF2). In the present study METTL3 was targeted using two different siRNAs. HepG2 viability and proliferative activity were conducted by Trypan blue exclusion test and cell proliferation assay, respectively. We revealed that HepG2 viability and proliferative activity were significantly reduced in transfected cells compared to untransfected ones (p< 0.05). Small interference RNA targeted METTL3 significantly reduced the expression of METTL3 in transfected cells, which resulted in up-regulated TP53 and down-regulated eEF2 expression. So, targeting METTL3 significantly hindered HepG2 viability, proliferative activity, and induced apoptosis. Also, post-transcription METTL3 silencing alleviated the disrupted expression of TP53 and eEF2. Therefore, the inhibition of m6A writer enzyme might be a prospective druggable target for Hepatocellular carcinoma (HCC) therapy.

Genomic and Molecular Analyses Identify Molecular Subtypes of Pancreatic Cancer Recurrence

Genomic and Molecular Analyses Identify Molecular Subtypes of Pancreatic Cancer Recurrence

Identification of medicinal compounds as potential inhibitors for mutated isocitrate dehydrogenases against chondrosarcoma.

Chondrosarcoma is the third most common cartilaginous bone tumour that is insusceptible to radio- and chemotherapy and it is inclined to metastasis. These resistant qualities are facilitated by mutant variants of isocitrate dehydrogenases (IDH) 1-2 enzyme. These mutant enzymes promote oncogenesis of chondrocytes by changing their epigenetic wardrobe leading to tumour formation. Presently, there are lack of drugs available to be exploited as a remedy for this disease. On the other hand, majority of chemotherapeutic drugs induce cytotoxicity in the cancer cells at the cost of harming surrounding healthy cells, jeopardizing human life. The current study is focused on screening various medicinal compounds against IDH1 and IDH2 combined with insilico gene expression, cancer cells cytotoxicity and ADMET (absorption, distribution, metabolism, excretion and toxicity) studies to elucidate the molecular mechanism against chondrosarcoma and also to uncover pharmacokinetic profile of these compounds. Screening of 5000+compounds filtered two efficacious compounds (Artocarpetin and 5-Galloylquinic acid) capable of establishing hydrogen bond connections with both IDH variants. Other studies showed that these compounds downregulate ITGAV, CARPIN1, CCL5 and COG5 and TNFRSF10B gene that reduces chondrogenesis and inflammation, Artocarpetin and 5-galloylquinic acid are TP53 expression enhancer and inhibit MM9 expression that promote immunomodulation and apoptosis in these cancers. These compounds are both active against CHSA8926 and CHSA011 cell line of chondrosarcoma. However, the ADME profile of 5-galloylquinic acid is slightly unsatisfactory based on druglikness and bioavailability score criteria as compared to artocarpetin. Both of these compounds are class-5 chemicals and require high doses to elicit adverse response. Our results suggest that artocarpetin and 5-galloylquinic acid are efficacious drug candidates and could be further exploited to validate these findings in vitro.

TOXOPLASMA GONDII КАК ФАКТОР ПРОГРЕССИИ КАНЦЕРОГЕННЫХ ПРОЦЕССОВ НА МОЛЕКУЛЯРНО-ГЕНЕТИЧЕСКОМ УРОВНЕ У ПРОМЕЖУТОЧНОГО ХОЗЯИНА

Objectives. To study Toxoplasma gondii as a factor of carcinogenic processes progression at the molecular-genetic level in an intermediate host. Material and methods. In the experiment, the expression of the proto-oncogenes survivin (BIRC5), epidermal growth factor (ErbB-2/HER2-Neu), GLI, vascular endothelial growth factor (VEGF) and anti-oncogene TP53 was determined in comparison with the reference genes - β-actin (ACTB) and GAPDH by means of PCR analysis in the tissues of animals with C6 tumor in situ infected with toxoplasma in different doses. A statistical comparison was made between the data of the experimental groups, depending on the dose of infection and the stage of the parasite development. Results. It has been revealed that toxoplasma can cause an increase in the expression of survivin (BIRC5), VEGF, ErbB-2/HER2-Neu, GLI in the tumors, lungs, liver, spleen, brain, both when invaded at a dose of 25 toxoplasma tachyzoites per 1 g of body weight (5000 tachyzoites per female) and when infected at a dose of 50 toxoplasma tachyzoites per 1 g of body weight (10000 tachyzoites per female). The degree of an increased expression of proto-oncogenes is directly dependent on the dose and stage of the parasite development. Infection of female rats having glioma with toxoplasma tachyzoites leads to a decrease in the expression of the anti-oncogene TP53 in the tissues of glioma, the lungs, liver, spleen, and brain of female rats. The decrease in the expression of TP53 depends on the dose of infection and the stage of toxoplasma development. Conclusions. Experimental toxoplasmosis causes an increase in the expression of BIRC5, ErbB-2/HER2-Neu, GLI, VEGF and a decrease in the expression of the anti-oncogene TP53, which can lead to the development of aggressive blastomogenic processes in mammalian tissues.

Effects of water-soluble components of atmospheric particulates from rare earth mining areas in China on lung cancer cell cycle

BackgroundThis study aims to investigate the effects of water soluble particulate matter (WSPM) on the viability and protein expression profile of human lung adenocarcinoma cell A549 in the Bayou Obo rare earth mining area, and explore the influence of WSPM on the A549 cell cycle.ResultsIt was found that WSPM can inhibit the viability of A549 cells and induce cell arrest in the G2/M phase. Compared with controls, exposure to WSPM10 and WSPM2.5 induced 134 and 116 proteins to be differentially expressed in A549 cells, respectively. In addition, 33 and 31 differentially expressed proteins were further confirmed, and was consistent with the proteomic analysis. The most prominent enrichment in ribosome-associated proteins were presented. When RPL6, RPL13, or RPL18A gene expression was inhibited, A549 cells were arrested in the G1 phase, affecting the expression of Cyclin D1, p21, RB1, Cyclin A2, Cyclin B1, CDC25A, CDK2, CHEK2 and E2F1. Furthermore, the La3+, Ce3+, Nd3+ and F- in WSPM also inhibited the viability of A549 cells. After 24 h of exposure to 2 mM of NaF, A549 cells were also arrested in the G2/M phase, while the other three compounds did not have this effect. These four compounds affected the cell cycle regulatory factors in A549 cells, mainly focusing on effecting the expression of CDK2, CDK4, RB1, ATM, TP53 and MDM2 genes. These results are consistent with the those from WSPM exposure.ConclusionsThese results revealed that WSPM from rare earth mines decreased the viability of A549 cells, and induced cell cycle G2/M phase arrest, and even apoptosis, which may be independent of the NF-κB/MYD88 pathway, and be perceived by the TLR4 receptor. The dysfunction of the cell cycle is correlated to the down-expression of ribosomal proteins (RPs). However, it is not the direct reason for the A549 cell arrest in the G2/M phase. La3+, Ce3+, and F- are probably the main toxic substances in WSPM, and may be regulate the A549 cell cycle by affecting the expression of genes, such as MDM2, RB1, ATM, TP53, E2F1, CDK2 and CDK4. These results indicate the importance for further research into the relationship between APM and lung cancer.

Tissue-specific expression of p73 and p63 isoforms in human tissues

p73 and p63 are members of the p53 family that exhibit overlapping and distinct functions in development and homeostasis. The evaluation of p73 and p63 isoform expression across human tissue can provide greater insight to the functional interactions between family members. We determined the mRNA isoform expression patterns of TP73 and TP63 across a panel of 36 human tissues and protein expression within the highest-expressing tissues. TP73 and TP63 expression significantly correlated across tissues. In tissues with concurrent mRNA expression, nuclear co-expression of both proteins was observed in a majority of cells. Using GTEx data, we quantified p73 and p63 isoform expression in human tissue and identified that the α-isoforms of TP73 and TP63 were the predominant isoform expressed in nearly all tissues. Further, we identified a previously unreported p73 mRNA product encoded by exons 4 to 14. In sum, these data provide the most comprehensive tissue-specific atlas of p73 and p63 protein and mRNA expression patterns in human and murine samples, indicating coordinate expression of these transcription factors in the majority of tissues in which they are expressed.

Tumor suppressor RBM24 inhibits nuclear translocation of CTNNB1 and TP63 expression in liver cancer cells.

RNA-binding protein 24 (RBM24) has been shown to play tumor-suppressive functions in various types of cancer. The present study aimed to investigate the role of RBM24 in liver cancers and its downstream mechanisms. The present study demonstrated that RBM24 functioned as a tumor suppressor in liver cancer cells, and inhibited nuclear translocation of β-catenin and tumor protein 63 expression by immunocytochemistry. In addition, RBM24 could suppress sphere formation in a multicellular tumor spheroid model of liver cancer cells. In conclusion, it is hypothesized that RBM24 is a tumor suppressor of liver cancer cells, which could be a potential novel therapeutic target for treatment of patients with liver cancer.

Integrative Bioinformatics Study of Tangeretin Potential Targets for Preventing Metastatic Breast Cancer.

Agents that target metastasis are important to improve treatment efficacy in patients with breast cancer. Tangeretin, a citrus flavonoid, exhibits antimetastatic effects on breast cancer cells, but its molecular mechanism remains unclear. Tangeretin targets were retrieved from PubChem, whereas metastatic breast cancer regulatory genes were downloaded from PubMed. In total, 58 genes were identified as potential therapeutic target genes of tangeretin (PTs). GO and KEGG pathway enrichment analyses of PTs were performed using WebGestalt (WEB-based Gene SeT AnaLysis Toolkit). The PPI network was analyzed using STRING-DB v11.0 and visualized by Cytoscape software. Hub genes were selected on the basis of the highest degree score as calculated by the CytoHubba plugin. Genetic alterations of the PTs were analyzed using cBioPortal. The prognostic values of the PTs were evaluated with the Kaplan–Meier plot. The expression of PTs across breast cancer samples was confirmed using GEPIA. The reliability of the PTs in metastatic breast cancer cells was validated using ONCOMINE. Molecular docking was performed to foresee the binding sites of tangeretin with PIK3Cα, MMP9, PTGS2, COX-2, and IKK. GO analysis showed that PTs participate in the biological process of stimulus response, are the cellular components of the nucleus and the membrane, and play molecular roles in enzyme regulation. KEGG pathway enrichment analysis revealed that PTs regulate the PI3K/Akt pathway. Genetic alterations for each target gene were MTOR (3%), NOTCH1 (4%), TP53 (42%), MMP9 (4%), NFKB1 (3%), PIK3CA (32%), PTGS2 (15%), and RELA (5%). The Kaplan–Meier plot showed that patients with low mRNA expression levels of MTOR, TP53, MMP9, NFKB1, PTGS2, and RELA and high expression of PIK3CA had a significantly better prognosis than their counterparts. Further validation of gene expression by using GEPIA revealed that the mRNA expression of MMP9 was significantly higher in breast cancer tissues than in normal tissues, whereas the mRNA expression of PTGS2 showed the opposite. Analysis with ONCOMINE demonstrated that the mRNA expression levels of MMP9 and NFKB1 were significantly higher in metastatic breast cancer cells than in normal tissues. The results of molecular docking analyses revealed the advantage of tangeretin as an inhibitor of PIK3CA, MMP9, PTGS2, and IKK. Tangeretin inhibits metastasis in breast cancer cells by targeting TP53, PTGS2, MMP9, and PIK3CA and regulating the PI3K/Akt signaling pathway. Further investigation is needed to validate the results of this study.

Abstract 2090: TP73 expression may be influenced by DNA methylation in human tumorigenesis

Abstract Epigenetic events that cause alterations in gene expression are common in human cancers. The connection between TP73 expression and its epigenetic functionality in tumorigenesis has scarcely been explored. As a transcription factor, TP73 (aka, p73) like its cousin, p53, is activated in response to DNA damage and regulates the expression of downstream genes involved in cell cycle arrest and apoptosis. However, there are other compounding functions of this gene that reflect its non-tumor-related characteristics, thus making it very difficult to assess its specific role in tumorigenesis. Our previous work showed that DNA methylation activates TP73 expression in hepatocellular carcinoma (HCC) and gastrointestinal cancer. In this study, we determined TP73 expression in normal human mammary epithelial cells (HMECs), human non-cancerous Li-Fraumeni Syndrome (LFS) skin fibroblast cells, human breast cancer cell lines (MCF7, MDA-MB-231 &amp; MDA-MB-468), prostate cancer cell lines (LNCaP &amp; MDA-PCa2b), lung cancer cell lines (A549 &amp; NCI-H596), neuroblastoma cell lines (IMR32 &amp; SK-N-SH) and normal human skin fibroblast cell line (HS27). The results show that TP73 was expressed solely in cancer cells. Subsequent immunohistochemical analyses of TP73 expression in cancerous and adjacent non-cancerous liver tissues of HCC patients clearly showed that TP73 expression was exclusively evident in cancerous tissues but not in the adjacent normal liver tissues. Mechanistically, methylation-specific PCR and bisulfite sequencing studies revealed that TP73 promoter is activated only in cancer cells and this activation occurs via DNA methylation. Moreover, ChIP assays demonstrated that a CTCF (a chromosomal networking protein CCCTC binding factor) and tumor protein p53 (TP53) bind to TP73 promoter and regulate TP73 expression. Our observations demonstrate that a positive correlation in tumorigenesis exists between TP73 expression and DNA methylation in promoter regions of TP73. These findings suggest that TP73's role in carcinogenesis may prove to be pivotal for the development of future diagnostic and therapeutic applications. Citation Format: Zhixing Yao, David R. Yao, William Yu, Ahmed Malki, Zaki A. Sherif. TP73 expression may be influenced by DNA methylation in human tumorigenesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2090.

Abstract 1816: Phenogenomic characterization of immunomodulatory purinergic signaling in glioblastoma

Abstract INTRODUCTION: Extracellular purinergic signaling plays critical roles in the regulation of tumor growth and anti-tumor immunity via autocrine/paracrine binding of metabolites to receptors on neoplastic and non-neoplastic populations. Extracellular purine concentrations are principally mediated by the ectonucleotidase enzymes CD39 and CD73, which catabolize ATP to adenosine. Within the tumor microenvironment, neoplastic, immune, and stromal cells expressing these enzymes may co-localize to generate an immunosuppressive adenosine-rich niche. However, the cellular composition, spatial architecture and phenotypic properties of these tumor ecosystems and their relationship to tumor genotype have been poorly characterized. METHODS: We quantified CD73 expression by immunohistochemistry (IHC) in a cohort of CNS tumors [meningiomas(N=222), gliomas(N=244), ependymomas(N=44), medulloblastomas(N=24), craniopharyngiomas(N=38)]. We used publicly-available single-cell RNA-seq data and 36 marker multiplexed tissue imaging (t-CyCIF) of 139 clinically and genomically annotated glioblastomas to characterize CD39 and CD73 expressing populations, define immune architecture and tumor cell states at single cell resolution, evaluate spatial correlations, and identify markers of clinical outcome. Mass spectrometry imaging (MALDI-MSI) was employed to generate spatially-resolved quantification of purine metabolite levels in glioblastoma resections (N=9). RESULTS: IHC revealed strong CD73 expression in meningiomas and gliomas. Tumor CD73 expression was associated with poor progression-free-survival in IDH-wildtype glioblastoma (p=0.04). scRNA-seq in glioblastoma revealed that CD73 is predominantly expressed by tumor cell populations, while CD39 is predominantly expressed by monocytic (macrophage, microglial) populations. t-CyCIF showed enrichment of EGFR, Ki-67, and TP53 expression in CD73-high tumor cells at a single cell level independent of genotype, as well as significant spatial correlation between CD73 expression in tumor cells and CD39 expression in macrophages. MALDI-MSI showed significantly greater adenosine concentrations in glioblastomas with high CD73 expression. CD73 expression significantly correlated with EGFR amplification or C-terminal deletion (EGFRvIII or variants), type-II interferon signaling, and PD-L1 expression in glioblastoma. CONCLUSIONS: Phenogenomic analysis of purinergic signaling in glioblastoma revealed correlations between CD73 expression and genotype, adenosine concentration, and clinical outcome. Spatial analysis revealed interaction between macrophages CD39 expression and tumor cell CD73 expression, suggesting that these populations may interact to suppress anti-tumor immunity. Anti-CD73 therapy may provide therapeutic benefits in glioblastoma by blunting immunosuppressive and oncogenic adenosine signaling. Citation Format: Shannon Coy, Jia-Ren Lin, Shu Wang, Sylwia Stopka, Rumana Rashid, Jaeho Hwang, Prasidda Khadka, Philipp Euskirchen, Pratiti Bandopadhayay, Patrick Y. Wen, Peter K. Sorger, Nathalie Agar, Keith L. Ligon, Mehdi Touat, Sandro Santagata. Phenogenomic characterization of immunomodulatory purinergic signaling in glioblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1816.

Abstract LB098: Vulnerability of MTAP-deleted nasopharyngeal carcinoma to MAT2A inhibition

Abstract Nasopharyngeal carcinoma (NPC) is an EBV-associated cancer prevalent in Southern China and Southeast Asia. We have generated a comprehensive genomic profile of NPC using whole-genome sequencing (WGS) and established a catalogue of somatic alterations of this EBV-associated cancer. In addition to the significantly mutated genes reported in previous WES studies, our WGS study revealed recurrent structural variants (SVs) and copy number variants (CNVs) driving key oncogenic pathways, including cell cycle, NF-kappaB and TGF-beta signaling. While immediately druggable gene aberrations (e.g. PIK3CA mutations and FGFR3-TACC3 fusions) are found in only ~3-5% of NPC, a synthetic lethality-based target, homozygous deletion of MTAP defined by fine-mapping of CDKN2A/CDKN2B deletion breakpoints at chromosome 9p21.3 was frequently detected (34%). Notably, the study has also revealed mutual exclusivity among tumors with MTAP deletion and TP53 alterations (p=0.022). Loss of MTAP has further been validated in a cohort of advanced and recurrent tumors (16/50, 32%) by FISH analysis and immunohistochemistry staining. The high prevalence and clonal nature of MTAP deletion in NPC implicate synthetic lethal targeting of MTAP-deleted tumors as a potential precision treatment for NPC patients. Using a CRISPR-based MTAP-knockout cell line and MTAP-deleted patient derived xenograft (PDX), we revealed that MAT2A and PRMT5 inhibition selectively suppressed growth of MTAP-deleted NPC. Treatment with MAT2A inhibitor, FIADS-5, led to depleted PRMT5 activity and reduced symmetric arginine methylation (SAMe) in these in vitro and in vivo NPC models. In addition to selective growth inhibition, MAT2A inhibition also targeted various unique oncogenic properties in NPC. The FIADS-5 treatment was shown to induce TP53 and BAX expression, cellular differentiation and keratinization in these MTAP-deleted NPC. Our findings demonstrated the translational potential of targeting MTAP-deletion in this EBV-associated epithelial cancer. Citation Format: Yuk Yu Chan, Jeff P. Bruce, Vivian W.Y. Lui, Grace T. Y. Chung, Sai-Wah Tsao, Ka-Fai To, Trevor J. Pugh, Kwok-Wai Lo. Vulnerability of MTAP-deleted nasopharyngeal carcinoma to MAT2A inhibition [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB098.

Abstract 2459: Altered bioenergetics profile in prostate cancer cells treated with andrographolide

Abstract Prostate cancer (PCa) is the second leading cause of cancer deaths in the United States alone. An emerging area of cancer therapeutics is the combination of the standard-of-care treatment with natural products. Andrographolide, a labdane diterpenoid and the main bioactive component of the medicinal plant Andrographis paniculata, has shown a wide range of therapeutic potential, including cancer. Previous studies from our laboratory have demonstrated that Andrographolide induces a DNA damage response, including ATM gene upregulation, involving cell growth suppression, cell cycle arrest, and apoptosis in PCa in vitro. The ATM gene is an important regulator of p53 and is consider a master switch for the p53-family member p63. The p63 is a natural marker of the basal lamina in the normal prostate, while its expression is lost in 99% of prostatic adenocarcinomas. Like p53, the p63 protein is implicated in tumor suppression and inhibition of metastasis, and also plays a role in energy metabolism. In this study, we aim to (1) determine the role of Andrographolide on the expression of p63, and (2) determine the bioenergetics profile of PCa cells. Androgen-dependent (22Rv1) and androgen-independent (PC3) PCa cell lines were treated with Andrographolide (25µM) for 24 h and 48 h. The gene expression of TP63 was assessed by real-time quantitative PCR (RT-qPCR). At the protein level, the expression of p63 was evaluated by immunofluorescence. The bioenergetics profile was performed using the Agilent Seahorse XF Real-Time ATP Rate Assay to determine the ATP production from glycolysis and mitochondria in living PC3 and 22Rv1 PCa cells. RT-PCR analysis showed a significant upregulation of the TP63 gene with a fold-change of 2.2 (p&amp;lt; 0.05) and immunofluorescence analysis showed an increase in expression of p63 protein with a fold-change of 1.8 (p&amp;lt; 0.05) in 22Rv1 cells treated with Andrographolide. The bioenergetics profile of PC3 cells, 48 h after Andrographolide treatment, revealed a shift in the cytoplasmic to mitochondrial ATP production rate from 54.4% to 72.6% and from 45.6% to 27.4%, respectively. Similar results were obtained in 22Rv1 cells. These results confirmed that Andrographolide induces the expression of the tumor protein p63 in androgen-dependent 22Rv1 PCa cells and alters the bioenergetics profile of both PC3 and 22Rv1 PCa cells. Our findings suggest a novel mechanism in which Andrographolide promotes the expression of p63 as in normal cells, and transforms the bioenergetics by increasing glycolytic-ATP. Citation Format: Jesus Sosa, María Sánchez Vázquez, Sylvette Ayala-Peña, Carlos Torres Ramos, Magaly Martínez Ferrer. Altered bioenergetics profile in prostate cancer cells treated with andrographolide [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2459.

NR5A2 Is One of 12 Transcription Factors Predicting Prognosis in HNSCC and Regulates Cancer Cell Proliferation in a p53-Dependent Manner.

Head and neck squamous cell carcinoma (HNSCC) rank seventh among the most common type of malignant tumor worldwide. Various evidences suggest that transcriptional factors (TFs) play a critical role in modulating cancer progression. However, the prognostic value of TFs in HNSCC remains unclear. Here, we identified a risk model based on a 12-TF signature to predict recurrence-free survival (RFS) in patients with HNSCC. We further analyzed the ability of the 12-TF to predict the disease-free survival time and overall survival time in HNSCC, and found that only NR5A2 down-regulation was strongly associated with shortened overall survival and disease-free survival time in HNSCC. Moreover, we systemically studied the role of NR5A2 in HNSCC and found that NR5A2 regulated HNSCC cell growth in a TP53 status-dependent manner. In p53 proficient cells, NR5A2 knockdown increased the expression of TP53 and activated the p53 pathway to enhance cancer cells proliferation. In contrast, NR5A2 silencing suppressed the growth of HNSCC cells with p53 loss/deletion by inhibiting the glycolysis process. Therefore, our results suggested that NR5A2 may serve as a promising therapeutic target in HNSCC harboring loss-of-function TP53 mutations.

The Immune Subtypes and Landscape of Gastric Cancer and to Predict Based on the Whole-Slide Images Using Deep Learning.

BackgroundGastric cancer (GC) is a highly heterogeneous tumor with different responses to immunotherapy. Identifying immune subtypes and landscape of GC could improve immunotherapeutic strategies.MethodsBased on the abundance of tumor-infiltrating immune cells in GC patients from The Cancer Genome Atlas, we used unsupervised consensus clustering algorithm to identify robust clusters of patients, and assessed their reproducibility in an independent cohort from Gene Expression Omnibus. We further confirmed the feasibility of our immune subtypes in five independent pan-cancer cohorts. Finally, functional enrichment analyses were provided, and a deep learning model studying the pathological images was constructed to identify the immune subtypes.ResultsWe identified and validated three reproducible immune subtypes presented with diverse components of tumor-infiltrating immune cells, molecular features, and clinical characteristics. An immune-inflamed subtype 3, with better prognosis and the highest immune score, had the highest abundance of CD8+ T cells, CD4+ T–activated cells, follicular helper T cells, M1 macrophages, and NK cells among three subtypes. By contrast, an immune-excluded subtype 1, with the worst prognosis and the highest stromal score, demonstrated the highest infiltration of CD4+ T resting cells, regulatory T cells, B cells, and dendritic cells, while an immune-desert subtype 2, with an intermediate prognosis and the lowest immune score, demonstrated the highest infiltration of M2 macrophages and mast cells, and the lowest infiltration of M1 macrophages. Besides, higher proportion of EVB and MSI of TCGA molecular subtyping, over expression of CTLA4, PD1, PDL1, and TP53, and low expression of JAK1 were observed in immune subtype 3, which consisted with the results from Gene Set Enrichment Analysis. These subtypes may suggest different immunotherapy strategies. Finally, deep learning can predict the immune subtypes well.ConclusionThis study offers a conceptual frame to better understand the tumor immune microenvironment of GC. Future work is required to estimate its reference value for the design of immune-related studies and immunotherapy selection.

Overcoming Tyrosine Kinase Inhibitor Resistance to SEPT9-ABL1 Chimeric Fusion Protein Using CRM1 Inhibitors

ABL1 fusion genes, which have been reported in various hematological malignancies, are thought to contribute to leukemogenesis through aberrant ABL1 signaling and activating multiple downstream signals. Tyrosine kinase inhibitors (TKIs), such as imatinib and dasatinib, have been developed to inhibit the function of the most- characterized ABL1 fusion product, BCR-ABL1. Because TKIs target the ABL1 kinase domain, ABL1 fusion products are usually sensitive to TKIs both in vitro and in vivo .We previously identified the chimeric fusion gene SEPT9 - ABL1 in a case of T-prolymphocytic leukemia that was unexpectedly resistant to imatinib and dasatinib without mutations in the domains derived from ABL1. We proved that SEPT9-ABL1 exhibited TKI resistance in vitro and in vivo, as seen in theclinical course (Leuk Res 2014). The purpose of this study was to reveal the mechanism underlying TKI resistance and to overcome it in a specific way.SEPT9f-ABL1, which has the most typical characteristics among SEPT9 isoforms, was retrovirally transduced into interleukin-3 (IL-3)-dependent murine hematopoietic cell lines 32D and BaF3 cells to generate 32D/SEPT9-ABL1 and BaF3/SEPT9-ABL1 cells. 32D/BCR-ABL1 and BaF3/BCR-ABL1 cells were also generated as references. The 50% inhibitory concentration (IC50) of imatinib was higher with SEPT9-ABL1 than with BCR-ABL1 (in 32D cells and BaF3 cells, respectively), confirming that SEPT9-ABL1 contributed to TKI resistance.Because TP53 has been suggested to involved in TKI resistance, we first analyzed the TP53 expression and phosphorylation in these cells. Western blot revealed that TP53 was downregulated and less phosphorylated in the cells expressing SEPT9-ABL1 than in those with BCR-ABL1. These findings were consistent with the analysis using primary leukemic cells. Imatinib treatment reduced the TP53 expression in the cells expressing SEPT9-ABL1. When the cell pellets were fractioned, the TP53 expression in the cytoplasm was comparable between cells expressing SEPT9-ABL1 and those with BCR-ABL1 under imatinib treatment. However, the TP53 expression remained higher in the nucleus of the cells with BCR-ABL1 than in those with SEPT9-ABL1, suggesting that the decreased nuclear TP53 expression prevented the cells expressing SEPT9-ABL1 from undergoing apoptosis induced by imatinib.Because the distribution of TP53 in the nucleus and the cytoplasm is controlled by chromosomal region maintenance 1 (CRM1), a nuclear export receptor, we next evaluated the effects of CRM1 inhibition. When the cells were cultured with the combination of imatinib (1 µM) and KPT-185 (1 µM), TP53 was markedly accumulated in the cells expressing SEPT9-ABL1; however, no such accumulation was noted when cells were cultured with imatinib alone, suggesting that KPT-185 treatment enhanced the effect of imatinib in the cells expressing SEPT9-ABL1 through the inhibition of TP53 export from the nucleus. This combination dramatically increased the apoptotic cells with SEPT9-ABL1. To evaluate CRM1 inhibition in vivo, we utilized a subcutaneous tumor model with BaF3/SEPT9-ABL1 cells. Treatment with imatinib 20 mg/kg plus another CRM1 inhibitor (KPT-330, 20 mg/kg) led to the significant regression of tumors composed of BaF3/SEPT9-ABL1 cells compared to imatinib alone (p=0.029).In conclusion, decreased nuclear expression of TP53 is a possible mechanism underlying TKI resistance in cells harboring SEPT9-ABL1. CRM1 inhibition is an effective method of overcoming TKI resistance in cells with SEPT9-ABL1 through induction of the nuclear accumulation of TP53 and apoptosis. [Display omitted] DisclosuresAndo:NOVARTIS: Other: Donation to institute; Meiji Seika Pharma: Other: Donation to institute; CHUGAI PHARMACEUTICAL: Other: Donation to institute; TOYAMA CHEMICAL: Other: Donation to institute; MOCHIDA PHARMACEUTICAL: Other: Donation to institute; Sumitomo Dainippon Pharma: Other: Donation to institute; Eisai: Other: Donation to institute; Bristol-Myers Squibb: Other: Donation to institute; MSD: Other: Donation to institute; Kyowa Hakko Kirin: Other: Donation to institute; ALEXION: Other: Donation to institute; Takeda: Other: Donation to institute; Japan Blood Products Organization: Other: Donation to institute; Nippon Shinyaku: Other: Donation to institute; NIHON PHARMACEUTICAL: Other: Donation to institute; TAIHO: Other: Donation to institute; Asahi KASEI: Other: Donation to institute.

JAK2-Inhibitor Therapy Associated Lymphomas in Myelofibrosis: Distinct Clinico-Pathological Features Recapitulated in a Mouse Model

Background: Single cases of aggressive B-cell non-Hodgkin lymphomas upon treatment with the Janus kinase 1/2 (JAK1/2) inhibitor ruxolitinib in patients with myeloproliferative disorders (MPD) have been reported (Pardanani, Mayo Clin.Proc. 2011 ; Bhatt VR et al. J Natl Compr Canc Netw . 2015;13(3):281-28; Palmason et al. BMC Hematology 2015). However, incidence and pathogenesis remain enigmatic.Methods: We investigated 626 patients with myeloproliferative neoplasms diagnosed at the Medical University of Vienna between 1997 and 2016. Of these, 69 patients with primary or secondary myelofibrosis were treated with JAK2 -inhibitors since 2009. Data on secondary malignancies were retrieved from our MPN database. Detailed clinical, pathologic and genetic data were obtained in patients developing lymphoma. These observations were recapitulated in a Stat1 knock-out mouse model (Stat1-/- mice).Results: B-cell lymphomas developed in 4 out of 69 patients (5.8%) upon ruxolitinib treatment compared to only 2 of 557 (0.36%) in the control group (16-fold increased risk, p=0.0017). The median time to lymphoma diagnosis was 25 months after ruxolitinib initiation (Table 1). Two lymphoma patients had been pre-treated with alkylating agents before ruxolitinib, one with hydroxyurea, the JAK -inhibitor fedratinib and ruxolitinib, and one received ruxolitinib only. All lymphomas were of aggressive CD19+ B-cell type (3 DLBCL, 1 HG BCL NOS) and showed distinct features with extranodal involvement and/or bone marrow infiltration (3/4), IPI of 2 or greater, and high MYC, and TP53 expression. Genetic analysis revealed abnormalities in MYC, BCL2, BCL6 or TP53 genes (Table 1). Targeted sequencing in 2 patients showed inactivating mutations in the B2M, CDKN2A, or TP53 genes. No JAK2 -mutation was found in the lymphomas. Three of four patients responded to anti-lymphoma therapy, but 3 patients eventually died from lymphoma or sAML. Of note, the clinical, and pathogenetic features closely resembled those of the published cases and 2 cases seen at a different institution (Paris, Hospital Saint-Louis).Mice deficient for the JAK kinase target STAT1 mirrored the course of the human disease: 16 of 24 Stat1-/- mice developed myeloid hyperplasia with splenomegaly and a massive expansion of myeloid blasts in bone marrow and peripheral blood. Lowering the load of myeloid blasts by ATRA or ruxolitinib led to B-cell proliferation. Transplantation of bone marrow from diseased Stat1-/- mice resulted in aggressive B-cell lymphomas displaying strikingly similar features to the human lymphomas with upregulation of c-Myc and Bcl-2 and downregulation of B2m (ß2-microglobulin) and Cdkn2a . STAT3 and STAT5 were not activated in these B-cell lymphomas indicating that the JAK/STAT pathway is dispensable for B cell transformation. B cells from diseased Stat1-/- mice gave rise to stable growth-factor independent cell lines, underlining their high grade of transformation.Conclusion. Inhibition of the JAK/STAT1 pathway in myeloproliferative diseases appears to provoke the development of a distinct type of aggressive B-cell lymphoma. In myelofibrosis treated with a JAK2 inhibitor 5 to 6% of patients are affected. Further investigations to identify potential risk factors are ongoing. [Display omitted] DisclosuresSperr:Celgene: Consultancy, Honoraria; Amgen: Consultancy, Honoraria, Research Funding; Phadia: Research Funding; Meda: Research Funding; Teva: Honoraria; Novartis: Other: Register. Staber:Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Gilad: Honoraria, Membership on an entity's Board of Directors or advisory committees; Morphosys: Membership on an entity's Board of Directors or advisory committees; Abbie: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria; MSD: Honoraria; Amgen: Honoraria; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees. Valent:Blueprint: Research Funding; Novartis: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; Incyte: Honoraria; BMS: Honoraria; Ariad: Honoraria, Research Funding; Pfizer: Honoraria; Teva: Honoraria; Deciphera: Honoraria, Research Funding. Hoermann:Gilead: Honoraria, Research Funding; Ariad: Honoraria; Amgen: Honoraria; Novartis: Honoraria. Kiladjian:Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; AOP Orphan: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees. Krauth:Novartis: Honoraria; Celgene: Honoraria; AOP Orphan Pharmaceuticals AG: Honoraria; BMS: Honoraria; Takeda: Honoraria; Janssen Cilag: Honoraria; Amgen: Honoraria. Jaeger:Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses; Novartis Pharmaceuticals Corporation: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees. Gisslinger:PharmaEssentia: Consultancy, Honoraria; AOP Orphan Pharmaceuticals AG: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Shire: Honoraria; Janssen Cilag: Honoraria; Takeda: Honoraria.

ABC Subtype, TP53 Mutation and BCL2 Overexpression are Associated with a Worse Outcome in Untreated Poor-Risk Young Diffuse Large B-Cell Lymphoma: Results from the Frontline Phase III BIO-DLBCL04 Study of the Fondazione Italiana Linfomi

ABC Subtype, TP53 Mutation and BCL2 Overexpression are Associated with a Worse Outcome in Untreated Poor-Risk Young Diffuse Large B-Cell Lymphoma: Results from the Frontline Phase III BIO-DLBCL04 Study of the Fondazione Italiana Linfomi

Midostaurin Shows Efficacy in Refractory Multiple Myeloma with TP53 Mutation and Elevated Expression of NTRK1, NTRK3 and AURKA

IntroductionMultiple myeloma (MM) displays enormous genetic complexity and heterogeneity, resulting in deregulated cell signaling, aberrant cell growth and survival. Although, recurrent myeloma alterations are well characterized, their impact on drug response is often unclear. To decipher complex gene-drug interactions, we comprehensively assessed drug responses of 100 MM samples to 142 drugs and compared to genomic, transcriptomic and cytogenetic information, plus clinical outcome of the individual patients. Our results reveal novel insights on i) drug response and resistance mechanisms, ii) genomic and transcriptomic indicators of drug response, and iii) drug repositioning possibilities.MethodsBone marrow aspirates were collected from MM patients (n=100; newly diagnosed (NDMM) n=34; relapsed/refractory (RRMM) n=66) and healthy individuals (n=14). CD138-enriched plasma cells were screened against 142 oncology drugs tested in a 10,000-fold concentration range. Whole exome and RNA sequencing were performed for 97 and 78 samples, respectively. To identify pharmacogenomic interactions, we applied differential gene expression profiling, ANOVA and regression analysis.ResultsOverall, the RRMM samples exhibited a larger number of mutations and also showed a larger number of clones as compared to NDMM samples (3.3±0.6 vs 2.7±0.6, p=6e-03). 32% of patient samples showing exquisite sensitivity to signal transduction inhibitors were characterized with high mutation burden (170± 31 compared to other patients 84±13,p=5e-03). Additionally, the gene expression profiles of the highly sensitive samples were associated with cell proliferation, corresponding to previously reported proliferation subtypes (UAMS) with poor prognosis. 14% of the samples that exhibited a multidrug resistant (MDR)phenotype and were resistant to proteasome inhibitors, immunomodulatory drugs and glucocorticoids, exhibited elevated expression of multidrug resistance genes ABCB1 (MDR1) and ABCC3 (MRP3). 28% of the resistant samples were from del(17p) patients. Integrative analysis allowed assimilation of multiple datasets and revealed putative molecular markers associated to individual drugs. NPM1 expression was found to associate with bromodomain inhibitor JQ1 sensitivity, while CCND1 and BMI1 expression correlated with sensitivity to BCL2 inhibitor venetoclax. A hyperdiploid gene expression signature was enriched in glucocorticoid responding patient samples. While RAS pathway mutations (NRAS, KRAS, NF1, and BRAF) were detected in 56% of the patient samples and are recognized as major driver events in MM, MEK/ERK inhibitor efficacy was limited to 55% of samples bearing clonal mutations to these genes. 20% of the patient samples harbored mutations in genes involved in DNA damage repair signaling, namely ATM, ATR, MSH3, BAX, TP53BP1, and TP73, in a mutually exclusive pattern. Patients with these mutations had a high relapse rate, poor overall survival (HR=3.2,95%CI 1.1-9.02), and displayed acquired sensitivity to PI3K-mTOR and HDAC inhibitors. Sensitivity to midostaurin, as observed in FLT3 mutated AML, was detected in a subgroup of RRMM samples (20%) with mutated TP53 and elevated expression of NTRK1, NTRK3 and AURKA .SummaryBased on their genomic and transcriptomic profiles, we could identify subsets of patients responding to approved drugs and novel compounds such as venetoclax, midostaurin and JQ1 exhibiting potent activity in myeloma. In support of previous studies, we found that alterations in DNA damage signaling pathways contribute to poor prognosis, however, samples with these mutations showed enhanced sensitivity to PI3K-mTOR and HDAC inhibitors. Our study demonstrates that molecular information and ex vivo drug profiling may be useful to develop tailored treatment strategies, identify responding patients and guide treatment decision, especially for relapsed/refractory myeloma patients. DisclosuresSilvennoinen:Celgene,Takeda, Sanofi, Jansen-Cilag: Honoraria, Research Funding. Porkka:Novartis: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; Bristol-Myers Squibb: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding. Heckman:Novartis: Research Funding; Orion Pharma: Research Funding; Celgene: Research Funding; Pfizer: Research Funding; IMI2 project HARMONY: Research Funding.