scholarly journals Loss of Neuroligin 4X Induces an Intrinsic Innate Immune Response in TNBC

Author(s):  
Alehegne Yirsaw ◽  
Muhammad G Omar ◽  
Isra A Elhussin ◽  
Dequarius King ◽  
Henry J Henderson ◽  
...  

Abstract BackgroundImmune checkpoint blockade therapies, which act on T cell inhibitory receptors, including CTLA-4 and PD-1, induce durable responses across diverse cancers. However, most patients do not respond to these therapies, and initially responsive cancers may relapse. Identifying molecular mechanisms that influence therapeutic responses and resistance is critical to realize the full therapeutic potential of immune checkpoint inhibitors. The presence of immune infiltrates in the tumor microenvironment is associated with positive outcomes in breast cancer, specifically in triple-negative breast cancer (TNBC). The underlying mechanisms driving this response are unclear. We have previously identified Neuroligin 4X (NLGN4X) as a protein expressed in TNBC.MethodsBioinformatic analysis was used for pathway analysis of TCGA TNBC patient dataset. Immunohistochemistry was performed on breast cancer tissue microarray for NLGN4X protein expression. RNA-seq was performed on MDA-MB-231 breast cancer cells for differential gene expression upon gene knockdown. Cytokine array, western blot, cell adhesion array and Nanostring was performed to determine the role of NLGN4X in TNBC.ResultsIn this study, we report that NLGN4X expression is lost in breast cancer with lymph node metastasis. Its expression negatively correlates with immune markers in vitro, The Cancer Genome Atlas (TCGA) TNBC patient dataset, and metastatic breast cancer tissues. RNA-seq analysis of the MDA-MB-231 breast cancer cell line, silenced for NLGN4X by siRNA showed more than 500 differentially regulated genes. GSEA analysis of these genes revealed upregulation of interferon signaling pathway, cytokine signaling, and downregulation of cholesterol metabolism and lipid metabolism pathways. NLGN4X knockdown induced loss of cell adhesion, epithelial to mesenchymal transition (EMT), and MAVS-IRF7 signaling in breast cancer cells. Interestingly, analysis of the TCGA dataset of 104 TNBC patients also showed interferon signaling (IFN) as one of the significant pathways downregulated in TNBC patients expressing NLGN4X.ConclusionLoss of NLGN4X leads to innate immune activation in breast cancer and coincides with an aggressive phenotype of cancer. This study identifies the role of NLGN4X in regulating interferon signaling and immune microenvironment in TNBC.

2021 ◽  
Author(s):  
Alehegne Yirsaw ◽  
Muhammad G Omar ◽  
Isra A Elhussin ◽  
Dequarius King ◽  
Henry J Henderson ◽  
...  

Abstract Background Immune checkpoint blockade therapies, which act on T cell inhibitory receptors, including CTLA-4 and PD-1, induce durable responses across diverse cancers. However, most patients do not respond to these therapies, and initially responsive cancers may relapse. Identifying molecular mechanisms that influence therapeutic responses and resistance is critical to realize the full therapeutic potential of immune checkpoint inhibitors. The presence of immune infiltrates in the tumor microenvironment is associated with positive outcomes in breast cancer, specifically in triple-negative breast cancer (TNBC). The underlying mechanisms driving this response are unclear. We have previously identified Neuroligin 4X (NLGN4X) as a protein expressed in TNBC.Methods Bioinformatic analysis was used for pathway analysis of TCGA TNBC patient dataset. Immunohistochemistry was performed on breast cancer tissue microarray for NLGN4X protein expression. RNA-seq was performed on MDA-MB-231 breast cancer cells for differential gene expression upon gene knockdown. Cytokine array, western blot, cell adhesion array and Nanostring was performed to determine the role of NLGN4X in TNBC.Results In this study, we report that NLGN4X expression is lost in breast cancer with lymph node metastasis. Its expression negatively correlates with immune markers in vitro, The Cancer Genome Atlas (TCGA) TNBC patient dataset, and metastatic breast cancer tissues. RNA-seq analysis of the MDA-MB-231 breast cancer cell line, silenced for NLGN4X by siRNA showed more than 500 differentially regulated genes. GSEA analysis of these genes revealed upregulation of interferon signaling pathway, cytokine signaling, and downregulation of cholesterol metabolism and lipid metabolism pathways. NLGN4X knockdown induced loss of cell adhesion, epithelial to mesenchymal transition (EMT), and MAVS-IRF7 signaling in breast cancer cells. Interestingly, analysis of the TCGA dataset of 104 TNBC patients also showed interferon signaling (IFN) as one of the significant pathways downregulated in TNBC patients expressing NLGN4X.Conclusion Loss of NLGN4X leads to innate immune activation in breast cancer and coincides with an aggressive phenotype of cancer. This study identifies the role of NLGN4X in regulating interferon signaling and immune microenvironment in TNBC.


2014 ◽  
Vol 60 (3) ◽  
pp. 322-331 ◽  
Author(s):  
E.A. Avilova ◽  
O.E. Andreeva ◽  
V.A. Shatskaya ◽  
M.A. Krasilnikov

The main goal of this work was to study the intracellular signaling pathways responsible for the development of hormone resistance and maintaining the autonomous growth of breast cancer cells. In particular, the role of PAK1 (p21-activated kinase 1), the key mitogenic signaling protein, in the development of cell resistance to estrogens was analyzed. In vitro studies were performed on cultured breast cancer cell lines: estrogen-dependent estrogen receptor (ER)-positive MCF-7 cells and estrogen-resistant ER-negative HBL-100 cells. We found that the resistant HBL-100 cells were characterized by a higher level of PAK1 and demonstrated PAK1 involvement in the maintaining of estrogen-independent cell growth. We have also shown PAK1 ability to up-regulate Snail1, one of the epithelial-mesenchymal transition proteins, and obtained experimental evidence for Snail1 importance in the regulation of cell proliferation. In general, the results obtained in this study demonstrate involvement of PAK1 and Snail1 in the formation of estrogen-independent phenotype of breast cancer cells showing the potential role of both proteins as markers of hormone resistance of breast tumors.


2019 ◽  
Vol 51 (10) ◽  
pp. 1008-1015 ◽  
Author(s):  
Shusheng Qiu ◽  
Wei Hu ◽  
Qiuhong Ma ◽  
Yi Zhao ◽  
Liang Li ◽  
...  

Abstract Tumor necrosis factor α-induced protein 8-like-1 (TIPE1) functions as an activator or a repressor in a tumor cell type-specific manner. However, the role of TIPE1 in breast cancer, especially regarding metastasis, is unknown. In this study, we aimed to investigate the TIPE1 expression in breast cancer tissues, the biological functions, and the underlying mechanisms of TIPE1 regarding the metastatic properties of breast cancer cells. The results of immunohistochemical staining and western blot analysis indicated that TIPE1 expression was associated with tumor size and lymph node metastasis, and the expression of TIPE1 was downregulated in the tissues of patients with lymph node metastasis. Transwell and wound healing assay results showed that TIPE1 inhibited the invasive and migratory capacities of breast cancer cells. Moreover, the epithelial-mesenchymal transition (EMT) was suppressed in TIPE1-overexpressing cells, as demonstrated by western blot analysis. In addition, western blot analysis also showed that TIPE1 reduced the expression levels of MMP2 and MMP9 and decreased the phosphorylation level of ERK. These results suggested that TIPE1 might suppress the invasion and migration of breast cancer cells and inhibit EMT primarily via the ERK signaling pathway. Our findings revealed the anti-tumor metastasis role of TIPE1 in breast cancer and TIPE1 might be a new candidate prognostic indicator and a potential molecular target for the treatment of breast cancer.


2019 ◽  
Vol 51 (8) ◽  
pp. 791-798 ◽  
Author(s):  
Lu Min ◽  
Chuanyang Liu ◽  
Jingyu Kuang ◽  
Xiaomin Wu ◽  
Lingyun Zhu

Abstract MicroRNAs (miRNAs) are a class of endogenous noncoding genes that regulate gene expression at the posttranscriptional level. In recent decades, miRNAs have been reported to play important roles in tumor growth and metastasis, while some reported functions of a specific miRNA in tumorigenesis are contradictory. In this study, we reevaluated the role of miR-214, which has been reported to serve as an oncogene or anti-oncogene in breast cancer metastasis. We found that miR-214 inhibited breast cancer via targeting RNF8, a newly identified regulator that could promote epithelial–mesenchymal transition (EMT). Specifically, the survival rate of breast cancer patients was positively correlated with miR-214 levels and negatively correlated with RNF8 expression. The overexpression of miR-214 inhibited cell proliferation and invasion of breast cancer, while suppression of miR-214 by chemically modified antagomir enhanced the proliferation and invasion of breast cancer cells. Furthermore, miR-214 could modulate the EMT process via downregulating RNF8. To our knowledge, this is the first report that reveals the role of the miR-214–RNF8 axis in EMT, and our results demonstrate a novel mechanism for miR-214 acting as a tumor suppressor through the regulation of EMT.


2009 ◽  
Vol 7 (5) ◽  
pp. 634-644 ◽  
Author(s):  
Xiaoying Zhang ◽  
Ulka Shrikhande ◽  
Bethany M. Alicie ◽  
Qing Zhou ◽  
Robert L. Geahlen

Tumor Biology ◽  
2017 ◽  
Vol 39 (9) ◽  
pp. 101042831771463 ◽  
Author(s):  
Farheen Alam ◽  
Fatima Mezhal ◽  
Hussain EL Hasasna ◽  
Vidhya A Nair ◽  
SR Aravind ◽  
...  

This study aimed to analyze the expression of microRNAs in relation to p53 status in breast cancer cells and to delineate the role of Moesin in this axis. We used three isogenic breast carcinoma cell lines MCF7 (with wild-type p53), 1001 (MCF7 with mutated p53), and MCF7-E6 (MCF7 in which p53 function was disrupted). MicroRNA expression was analyzed using microarray analysis and confirmed by real-time polymerase chain reaction. The 1001 clone with mutant p53 showed 22 upregulated and 25 downregulated microRNAs. The predicted targets of these 47 microRNAs were >700 human genes belonging to interesting functional groups such as stem cell development and maintenance. The most significantly downregulated microRNAs in the p53-mutant cell line were from the miR-200 family. We focused on miR-200c which targets many transcripts involved in epithelial-to-mesenchymal transition including Moesin. We found that Moesin was expressed in 1001 but not in its p53 wild-type parental MCF7 consistent with the observed mesenchymal features in the 1001, such as vimentin positivity, E-cadherin negativity, and ZEB1 positivity in addition to the morphological changes. After Moesin silencing, the p53-mutant cells 1001 reverted from mesenchymal-to-epithelial phenotype and showed subtle reduction in migration and invasion and loss of ZEB1 and SNAIL expression. Interestingly, Moesin silencing restored the 1001 sensitivity to Doxorubicin. These results indicate that loss of miR-200c, as a consequence of p53 mutation, can upregulate Moesin oncogene and thus promote carcinogenesis. Moesin may play a role in metastasis and drug resistance of breast cancer.


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