genome-wide-crispr-screen-for-unveiling-radiosensitive-radioresistant

Genome-Wide CRISPR Screen for Unveiling Radiosensitive and Radioresistant Genes

The CRISPR-Cas9 system has been harnessed and repurposed into a powerful genome editing tool. By leveraging this technology, researchers can precisely ...

zhongnan hospital of Wuhan University

Tumour-associated macrophages (TAMs) are one of the primary sources of PD-L1 expression in the tumour microenvironment (TME). Ionizing radiation (IR) promotes PD-L1 expression in tumour cells. However, the effect of IR on macrophage PD-L1 expression and the underlying mechanisms remain unclear. ATM kinase, as the key kinase for initiating DNA damage repair (DDR) process, is associated with innate immune STING axis activation. Here, we explored the molecular mechanism implicated in macrophage PD-L1 expression regulated by IR as well as the role of ATM kinase in this process. IR-regulated PD-L1 expression in macrophages and associated signalling pathways were explored by in vitro studies using murine and human macrophage cell lines. A colorectal xenograft murine model was employed to demonstrate the impact of targeting ATM and PD-L1 expression in TAMs following IR on growth of tumour in vivo. IR up-regulated PD-L1 expression in macrophages, which was further augmented by ATM kinase inhibition. ATM inhibition increased IR-induced DNA damage, which activated STING/interferon regulatory factor 3 (IRF3) signalling pathway and up-regulated type I interferon (IFN-I) expression in macrophages. IFN-I bound to the IFN α receptor 1 on macrophages, activated the downstream JAK1 and STAT1/3 signalling and eventually led to PD-L1 up-expression. ATM inhibition augmented IR-induced PD-L1 expression in macrophages and CD8 T cell infiltration, and promoted anti-tumour efficacy in vivo. These results suggested that ATM inhibition promoted IR-induced PD-L1 expression through the activation of innate immunity in TAMs, which provided a novel approach to enhance the anti-tumour efficacy of RT.

Ataxia telangiectasia mutated kinase inhibition promotes irradiation-induced PD-L1 expression in tumour-associated macrophages through IFN-I/JAK signalling pathway.

Radiotherapy has been widely used to treat various cancers, but its efficacy depends on the individual involved. Traditional gene-based machine-learning models have been widely used to predict radiosensitivity. However, there is still a lack of emerging powerful models, artificial neural networks (ANN), in the practice of gene-based radiosensitivity prediction. In addition, ANN may overfit and learn biologically irrelevant features.

Prediction of radiosensitivity and radiocurability using a novel supervised artificial neural network.

Anaplastic thyroid carcinoma (ATC) is a highly aggressive human malignancy without effective treatment. Yes-associated protein (YAP) is a critical effector of the Hippo pathway, which is essential in thyroid carcinogenesis. However, the underlying mechanisms of aberrant YAP expression in ATC are not completely understood. Ubiquitylation-related enzyme siRNA screening identified the ubiquitin protein ligase E3 component n-recognin 1 (UBR1) as a stabilizer of YAP in ATC cells. UBR1 deficiency reduced YAP protein levels and its target gene expression. UBR1 directly interacted with YAP and promoted its monoubiquitylation, competitively suppressing its polyubiquitylation and resulting in extended protein half-life. UBR1 depletion reduced ATC cell proliferation and migration in vitro. Xenograft tumor studies also suggested that UBR1 knockdown suppressed ATC cell growth in vivo. Furthermore, exogenous YAP expression partially reversed the inhibitive effects of UBR1 depletion on ATC cell proliferation and migration. Our studies demonstrated that UBR1 directly interacts with YAP and stabilized it in a monoubiquitylation-dependent manner, consequently promoting ATC tumorigenesis, suggesting that UBR1 might be a potentially therapeutic target for ATC treatment.

UBR1 promotes anaplastic thyroid carcinoma progression via stabilizing YAP through monoubiquitylation.

Over the past decades, researchers have continuously investigated the potential functions of long-chain polyunsaturated fatty acids (LCPUFAs) in cancers, including lung cancer. The ω-3 LCPUFAs, primarily consisting of eicosapentaenoic acid and docosahexaenoic acid, were found to modify inflammatory tumor microenvironment, induce cancer cell apoptosis and autophagy, and suppress tumor development when administered alone or with other therapeutical strategies. Although the precise anti-tumor mechanism has not been elucidated yet, ω-3 LCPUFAs are often used in the nutritional treatment of patients with cancer due to their ability to significantly improve patient's nutritional status, increase the sensitivity of tumor cells to treatments, and alleviate cancer-related complications. Here we present the key roles of ω-3 LCPUFAs as dietary supplementations in lung cancer, comprehensively review the recent progress on the underlying mechanisms of cancer cell regulation by ω-3 LCPUFAs, and introduce the application of ω-3 LCPUFAs in the clinical management of lung cancer and its malignant complications.

Article	Year
Ataxia telangiectasia mutated kinase inhibition promotes irradiation-induced PD-L1 expression in tumour-associated macrophages through IFN-I/JAK signalling pathway. Immunology\| PubMed ID: 36326481	2023
Prediction of radiosensitivity and radiocurability using a novel supervised artificial neural network. BMC cancer\| PubMed ID: 36451111	2022
UBR1 promotes anaplastic thyroid carcinoma progression via stabilizing YAP through monoubiquitylation. Scientific reports\| PubMed ID: 39174635	2024
Roles and therapeutic opportunities of ω-3 long-chain polyunsaturated fatty acids in lung cancer. iScience\| PubMed ID: 39834867	2025

Yuxin Zeng

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