Activation of the Ig Iα1 promoter by the transcription factor Ets-1 triggers Ig Iα1–Cα1 germline transcription in epithelial cancer cells

Abstract Background Increased reactive oxygen species (ROS) production by arsenic treatment in solid tumors showed to be effective to sensitize cancer cells to chemotherapies. Arsenic nano compounds are known to increase the ROS production in solid tumors. Methods In this study we developed arsenic–ferrosoferric oxide conjugated Nano Complex (As2S2–Fe3O4, AFCNC) to further promote the ROS induction ability of arsenic reagent in solid tumors. We screen for the molecular pathways that are affect by arsenic treatment in ESCC cancer cells. And explored the underlying molecular mechanism for the arsenic mediated degradations of the key transcription factor we identified in the gene microarray screen. Mouse xenograft model were used to further verify the synthetic effects of AFCNC with chemo and radiation therapies, and the molecular target of arsenic treatment is verified with IHC analysis. Results With gene expression microarray analysis we found Hippo signaling pathway is specifically affected by arsenic treatment, and induced ubiquitination mediated degradation of YAP in KYSE-450 esophageal squamous cell carcinoma (ESCC) cells. Mechanistically we proved PML physically interacted with YAP, and arsenic induced degradation PML mediated the degradation of YAP in ESCC cells. As a cancer stem cell related transcription factor, YAP 5SA over expressions in cancer cells are correlated with resistance to chemo and radiation therapies. We found AFCNC treatment inhibited the increased invasion and migration ability of YAP 5SA overexpressing KYSE-450 cells. AFCNC treatment also effectively reversed protective effects of YAP 5SA overexpression against cisplatin induced apoptosis in KYSE-450 cells. Lastly, with ESCC mouse xenograft model we found AFCNC combined with cisplatin treatment or radiation therapy significantly reduced the tumor volumes in vivo in the xenograft ESCC tumors. Conclusions Together, these findings suggested besides ROS, YAP is a potential target for arsenic based therapy in ESCC, which should play an important role in the synthetic effects of arsenic nano complex with chemo and radiation therapy.

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High-throughput single-cell chromatin accessibility CRISPR screens enable unbiased identification of regulatory networks in cancer

Nature Communications ◽

10.1038/s41467-021-23213-w ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Sarah E. Pierce ◽

Jeffrey M. Granja ◽

William J. Greenleaf

Keyword(s):

Transcription Factor ◽

Single Cell ◽

Cancer Cells ◽

High Throughput ◽

Regulatory Networks ◽

Temporal Dynamics ◽

Chromatin Accessibility ◽

Regulatory Regions ◽

Factor Binding ◽

Genome Wide

AbstractChromatin accessibility profiling can identify putative regulatory regions genome wide; however, pooled single-cell methods for assessing the effects of regulatory perturbations on accessibility are limited. Here, we report a modified droplet-based single-cell ATAC-seq protocol for perturbing and evaluating dynamic single-cell epigenetic states. This method (Spear-ATAC) enables simultaneous read-out of chromatin accessibility profiles and integrated sgRNA spacer sequences from thousands of individual cells at once. Spear-ATAC profiling of 104,592 cells representing 414 sgRNA knock-down populations reveals the temporal dynamics of epigenetic responses to regulatory perturbations in cancer cells and the associations between transcription factor binding profiles.

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CRISPR‐based knockin mutagenesis of the pioneer transcription factor FOXA1: optimization of strategies for multi‐allelic proteins in cancer cells

FEBS Open Bio ◽

10.1002/2211-5463.13139 ◽

2021 ◽

Author(s):

Shen Li ◽

Joseph P. Garay ◽

Colby A. Tubbs ◽

Hector L. Franco

Keyword(s):

Transcription Factor ◽

Cancer Cells ◽

Pioneer Transcription Factor

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Integrin α3β1 Promotes Invasive and Metastatic Properties of Breast Cancer Cells through Induction of the Brn-2 Transcription Factor

Cancers ◽

10.3390/cancers13030480 ◽

2021 ◽

Vol 13 (3) ◽

pp. 480

Author(s):

Rakshitha Pandulal Miskin ◽

Janine S. A. Warren ◽

Abibatou Ndoye ◽

Lei Wu ◽

John M. Lamar ◽

...

Keyword(s):

Breast Cancer ◽

Transcription Factor ◽

Cancer Cells ◽

Cell Invasion ◽

Breast Cancer Cells ◽

Gene Promoter ◽

Akt Inhibitor ◽

Integrin Α3β1

In the current study, we demonstrate that integrin α3β1 promotes invasive and metastatic traits of triple-negative breast cancer (TNBC) cells through induction of the transcription factor, Brain-2 (Brn-2). We show that RNAi-mediated suppression of α3β1 in MDA-MB-231 cells caused reduced expression of Brn-2 mRNA and protein and reduced activity of the BRN2 gene promoter. In addition, RNAi-targeting of Brn-2 in MDA-MB-231 cells decreased invasion in vitro and lung colonization in vivo, and exogenous Brn-2 expression partially restored invasion to cells in which α3β1 was suppressed. α3β1 promoted phosphorylation of Akt in MDA-MB-231 cells, and treatment of these cells with a pharmacological Akt inhibitor (MK-2206) reduced both Brn-2 expression and cell invasion, indicating that α3β1-Akt signaling contributes to Brn-2 induction. Analysis of RNAseq data from patients with invasive breast carcinoma revealed that high BRN2 expression correlates with poor survival. Moreover, high BRN2 expression positively correlates with high ITGA3 expression in basal-like breast cancer, which is consistent with our experimental findings that α3β1 induces Brn-2 in TNBC cells. Together, our study demonstrates a pro-invasive/pro-metastatic role for Brn-2 in breast cancer cells and identifies a role for integrin α3β1 in regulating Brn-2 expression, thereby revealing a novel mechanism of integrin-dependent breast cancer cell invasion.

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