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R3094 --> Breast cancer is the second leading cause of cancer‐related deaths in the US, primarily because breast cancer cells metastasize multiple vital organs, including the brain. Brain metastases, refractory to chemotherapy, occur in approximately 15‐35% of metastatic breast cancer cases. Current clinical management of brain metastases is limited to radiation therapy and surgical resection, and the median survival time for patients is very short. Therefore, a better therapeutic strategy against the disease is urgently needed. Emerging evidence suggests that metastasis's key steps are controlled by reversible epigenetic mechanisms, which could be targeted to prevent and treat the condition. Using a systematic in vivo shRNA screening approach, which targets around 100 actionable epigenetic regulators, we have identified several potential drivers and suppressors of breast cancer brain metastasis. Interestingly, one of the candidate regulators, N‐acetyltransferase 10 (NAT10), plays a role in catalyzing acetylation on specific RNA and protein substrates, while its regulatory mechanisms in breast cancer remain unclear. We found that knockdown of NAT10 suppresses breast cancer cell proliferation and migration in vitro and brain metastasis in vivo. We are leveraging transcriptomic and proteomic analyses to uncover key biological pathways regulated by NAT10. Here, we have demonstrated that this screening strategy is potent and can be applied to identify critical epigenetic regulators in other cancer types or metastatic organs. Our results allowed us to uncover the metastatic organotropism of the epigenes and develop a novel therapeutic regimen against metastatic diseases. [ABSTRACT FROM AUTHOR]

The present study investigated the expression and clinical significance of flavin‑containing monooxygenase 5 (FMO5) in colorectal cancer (CRC). The expression of FMO5 was detected by immunohistochemistry in 208 colon cancer tissues and 8 normal colon tissues. Then, the correlations of FMO5 expression with several clinicopathological features were evaluated. FMO5 mRNA expression from The Cancer Genome Atlas dataset was assessed for further validation. In addition, the association of the expression of FMO5 with prognosis was further evaluated by Kaplan‑Meier survival curves and Cox proportional hazards model. The FMO5 protein level in colon cancer tissues was significantly higher than that in normal colon tissues (P<0.001). Overexpression of FMO5 was associated with an advanced clinical stage of cancer (P=0.018) and lymph node metastasis (P=0.03). The TCGA dataset also demonstrated that FMO5 was upregulated in CRC with advanced clinical stage (P=0.047), lymph node metastasis (P=0.045) and distant metastasis (P=0.030). The Kaplan‑Meier survival curves showed that higher FMO5 mRNA indicated a shorter overall survival in patients with CRC compared with a low expression of FMO5 (P=0.029). Cox proportional hazards regression revealed that a high FMO5 mRNA level served as an independent prognostic factor for patients with CRC (hazard ratio, 2.865; 95% confidence interval, 1.116‑7.355; P=0.029). A high expression of FMO5 may serve roles in colorectal carcinogenesis and distant metastasis. FMO5 may be an independent predictive factor for the prognosis of CRC. [ABSTRACT FROM AUTHOR]

Enhancer of zeste homolog 2 (EZH2), the critical component of polycomb group protein family, has been demonstrated to be overexpressed in various types of human cancer, including hepatocellular carcinoma, breast, bladder and lung cancer. The mechanism of how EZH2 promotes oncogenesis has also been well studied. However, little is known about the role of EZH2 in colorectal cancer (CRC). The main purpose of the present study was to analyze the association between EZH2 expression and the clinicopathological features of CRC. Therefore, the mRNA and protein expression levels were analyzed in tumor tissues and adjacent non‑cancerous tissues by reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) and western blot analysis. The expression of EZH2 was demonstrated to be significantly increased in tumor tissues compared with adjacent noncancerous tissues, according to the results of western blot analysis and RT‑qPCR in the majority of cases. Patients with low EZH2 expression had a longer overall survival rate compared with those with high EZH2 expression. An analysis of the association between clinicopathological features and EZH2 expression indicated that high EZH2 expression was significantly associated with tumor stage, tumor size, histological differentiation and lymph node metastasis. Multivariate analysis demonstrated that high EZH2 expression was an independent predictor of overall survival. In conclusion, to the best of our knowledge, the data presented in the present study is the first to indicate that EZH2 is upregulated in CRC and may serve as a predictor of poor outcome for patients with CRC. [ABSTRACT FROM AUTHOR]

Identification of host genes essential for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection may reveal novel therapeutic targets and inform our understanding of coronavirus disease 2019 (COVID-19) pathogenesis. Here we performed genome-wide CRISPR screens in Vero-E6 cells with SARS-CoV-2, Middle East respiratory syndrome CoV (MERS-CoV), bat CoV HKU5 expressing the SARS-CoV-1 spike, and vesicular stomatitis virus (VSV) expressing the SARS-CoV-2 spike. We identified known SARS-CoV-2 host factors, including the receptor ACE2 and protease Cathepsin L. We additionally discovered pro-viral genes and pathways, including HMGB1 and the SWI/SNF chromatin remodeling complex, that are SARS lineage and pan-coronavirus specific, respectively. We show that HMGB1 regulates ACE2 expression and is critical for entry of SARS-CoV-2, SARS-CoV-1, and NL63. We also show that small-molecule antagonists of identified gene products inhibited SARS-CoV-2 infection in monkey and human cells, demonstrating the conserved role of these genetic hits across species. This identifies potential therapeutic targets for SARS-CoV-2 and reveals SARS lineage-specific and pan-CoV host factors that regulate susceptibility to highly pathogenic CoVs. • Developed monkey CRISPR library to screen pathogenic coronaviruses in Vero-E6 cells • Screens identified genes that are SARS-CoV-2, MERS-CoV, and pan-coronavirus specific • Therapeutic targets, including SMARCA4, identified for SARS-CoV-2 infection • HMGB1 is novel regulator of ACE2 expression and critical for viral entry To identify potential therapeutic targets for SARS-CoV-2 and related pathogenic coronaviruses, Wei et al. conduct genome-wide CRISPR screens in Vero-E6 cells using SARS-CoV-2, MERS-CoV, and pseudoviruses presenting SARS-CoV-1 or SARS-CoV-2 spike proteins. They identify pro-viral genes and pathways, including HMGB1 and the SWI/SNF chromatin remodeling complex, that are SARS lineage and pan-coronavirus specific, respectively, and demonstrate that HMGB1 is critical for SARS lineage viral entry because it has a critical role in ACE2 expression. [ABSTRACT FROM AUTHOR]

Genome-scale CRISPR-Cas9 Knockout Screening was applied to investigate novel targets in imatinib-resistant gastrointestinal stromal tumor (GIST). 20 genes and 2 miRNAs have been selected by total reads of sgRNA and sgRNA diversity, which has been further validated in imatinib-resistant GIST cells by CCK8 and qPCR analysis. Our study has finally revealed 9 genes (DBP, NR3C1, TCF12, TP53, ZNF12, SOCS6, ZFP36, ACYP1, and DRD1) involved in imatinib-resistant GIST-T1 cells. TP53 and SOCS6 may be the most promising candidate genes for imatinib-resistance due to the possible signaling pathway, such as apoptosis pathway and Wnt signaling pathway, JAK-STAT signaling pathway. It is necessary to perform more studies to discover novel targets in imatinib-resistant GIST, including DBP, NR3C1, TCF12, ZNF12, ZFP36, ACYP1 and DRD1. [ABSTRACT FROM AUTHOR]