scholarly journals DNAJB6 governs a novel regulatory loop determining Wnt/β-catenin signalling activity

2012 ◽  
Vol 444 (3) ◽  
pp. 573-580 ◽  
Author(s):  
Mitchell E. Menezes ◽  
Aparna Mitra ◽  
Lalita A. Shevde ◽  
Rajeev S. Samant
Keyword(s):  
Epithelial Mesenchymal Transition ◽  
Tumour Microenvironment ◽  
Negative Control ◽  
Signalling Pathway ◽  
Transition Analysis ◽  
Mesenchymal Transition ◽  
Tumour Metastasis ◽  
Dkk1 Expression ◽  
Exogenous Expression ◽  
Regulatory Loop

DKK1 (dickkopf 1 homologue) is a secreted inhibitor of the Wnt signalling pathway and a critical modulator of tumour promotion and the tumour microenvironment. However, mechanisms regulating DKK1 expression are understudied. DNAJB6 {DnaJ [HSP40 (heat-shock protein 40 kDa)] homologue, subfamily B, member 6} is an HSP40 family member whose expression is compromized during progression of breast cancer and melanoma. Inhibition of the Wnt/β-catenin signalling pathway by up-regulation of DKK1 is one of the key mechanisms by which DNAJB6 suppresses tumour metastasis and EMT (epithelial–mesenchymal transition). Analysis of the DKK1 promoter to define the cis-site responsible for its up-regulation by DNAJB6 revealed the presence of two binding sites for a transcriptional repressor, MSX1 (muscle segment homeobox 1). Our investigations showed that MSX1 binds the DKK1 promoter and inhibits DKK1 transcription. Interestingly, silencing DNAJB6 resulted in up-regulation of MSX1 concomitant with increased stabilization of β-catenin. ChIP (chromatin immunoprecipitation) studies revealed that β-catenin binds the MSX1 promoter and stabilization of β-catenin elevates MSX1 transcription, indicating that β-catenin works as a transcription co-activator for MSX1. Functionally, exogenous expression of MSX1 in DNAJB6-expressing cells promotes the mesenchymal phenotype by suppression of DKK1. Thus we have identified a novel regulatory mechanism of DNAJB6-mediated DKK1 transcriptional up-regulation that can influence EMT. DKK1 is a feedback regulator of β-catenin levels and thus our studies also define an additional negative control of this β-catenin/DKK1 feedback loop by MSX1, which may potentially contribute to excessive stabilization of β-catenin.

Tumour microenvironment: a non-negligible driver for epithelial−mesenchymal transition in colorectal cancer

2021 ◽  
Vol 23 ◽  
Author(s):  
Lei Han ◽  
Shuyi Wang ◽  
Chen Wei ◽  
Yan Fang ◽  
Sihao Huang ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Epithelial Mesenchymal Transition ◽  
Current Knowledge ◽  
Critical Role ◽  
Inflammatory Cells ◽  
Tumour Microenvironment ◽  
Tumour Cells ◽  
Mesenchymal Transition ◽  
Tumour Metastasis ◽  
Favourable Environment

Abstract Cancer remains the leading cause of death worldwide, and metastasis is still the major cause of treatment failure for cancer patients. Epithelial–mesenchymal transition (EMT) has been shown to play a critical role in the metastasis cascade of epithelium-derived carcinoma. Tumour microenvironment (TME) refers to the local tissue environment in which tumour cells produce and live, including not only tumour cells themselves, but also fibroblasts, immune and inflammatory cells, glial cells and other cells around them, as well as intercellular stroma, micro vessels and infiltrated biomolecules from the nearby areas, which has been proved to widely participate in the occurrence and progress of cancer. Emerging and accumulating studies indicate that, on one hand, mesenchymal cells in TME can establish ‘crosstalk’ with tumour cells to regulate their EMT programme; on the other, EMT-tumour cells can create a favourable environment for their own growth via educating stromal cells. Recently, our group has conducted a series of studies on the interaction between tumour-associated macrophages (TAMs) and colorectal cancer (CRC) cells in TME, confirming that the interaction between TAMs and CRC cells mediated by cytokines or exosomes can jointly promote the metastasis of CRC by regulating the EMT process of tumour cells and the M2-type polarisation process of TAMs. Herein, we present an overview to describe the current knowledge about EMT in cancer, summarise the important role of TME in EMT, and provide an update on the mechanisms of TME-induced EMT in CRC, aiming to provide new ideas for understanding and resisting tumour metastasis.

scholarly journals Recent Advances: The Imbalance of Immune Cells and Cytokines in the Pathogenesis of Hepatocellular Carcinoma

Diagnostics ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 338
Author(s):  
Kumar Jayant ◽  
Nagy Habib ◽  
Kai W. Huang ◽  
Jane Warwick ◽  
Ramesh Arasaradnam
Keyword(s):  
Hepatocellular Carcinoma ◽  
Immune Cells ◽  
Epithelial Mesenchymal Transition ◽  
Critical Role ◽  
Liver Parenchyma ◽  
Tumour Microenvironment ◽  
Tumour Immunity ◽  
Mesenchymal Transition ◽  
Increased Risk ◽  
Inflammatory State

Recent advancement in the immunological understanding of genesis of hepatocellular carcinoma (HCC) has implicated a decline in anti-tumour immunity on the background of chronic inflammatory state of liver parenchyma. The development of HCC involves a network of immunological activity in the tumour microenvironment involving continuous interaction between tumour and stromal cells. The reduction in anti-tumour immunity is secondary to changes in various immune cells and cytokines, and the tumour microenvironment plays a critical role in modulating the process of liver fibrosis, hepatocarcinogenesis, epithelial-mesenchymal transition (EMT), tumor invasion and metastasis. Thus, it is considered as one of primary factor behind the despicable tumour behavior and observed poor survival; along with increased risk of recurrence following treatment in HCC. The primary intent of the present review is to facilitate the understanding of the complex network of immunological interactions of various immune cells, cytokines and tumour cells associated with the development and progression of HCC.

scholarly journals Role of circadian rhythm disorders in EMT and tumor–immune interactions in endocrine-related cancers

2021 ◽  
Author(s):  
Eva Hadadi ◽  
Hervé Acloque
Keyword(s):  
Circadian Rhythm ◽  
Epithelial Mesenchymal Transition ◽  
Current Knowledge ◽  
Tumour Microenvironment ◽  
Tissue Level ◽  
Mesenchymal Transition ◽  
Animal Physiology ◽  
Molecular Machinery ◽  
Epithelial Tumours ◽  
Cell Dissemination

The circadian rhythm is a major environmental regulator of plants and animal physiology. The alternation of days and nights is translated at the cell and tissue level thanks to a molecular machinery, called the circadian clock. This clock controls in particular numerous endocrine functions and its imbalances can have serious consequences on homeostasis. This is particularly true for the development of endocrine-related cancers, like breast, ovarian and prostate cancer. Circadian rhythm disorder (CRD) not only affects key hormone levels (including estrogen, melatonin, insulin, glucagon, cortisol) but also favors a pro-inflammatory and immunosuppressive phenotype in the tumour microenvironment. This particular aspect is conducive to epithelial-mesenchymal transition (EMT) of solid epithelial tumours and cancer cell dissemination. It also favors resistance to chemo- and immunotherapy. Here, we discuss the current knowledge on this crosstalk between CRD, EMT and the immune microenvironment in endocrine-related cancers and its consequences for the development of efficient therapies.

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