Isoform-specific promotion of breast cancer tumorigenicity by TBX3 involves induction of angiogenesis

Abnormal activation of the Wnt3a/β-catenin signaling pathway promotes the expression of T-box transcription factor 3(TBX3) and the epithelial-mesenchymal transition pathway to mediate the occurrence of adenomyosis

BACKGROUND

T-box transcription factor 3(TBX3) is a transcription factor that can regulate cell proliferation, apoptosis, invasion, and migration in different tumor cells; however, its role in adenomyosis (ADM) has not been previously studied. Some of ADM's pathophysiological characteristics are similar to those of malignant tumors (e.g., abnormal proliferation, migration, and invasion).

METHODS AND RESULTS

We hypothesized that TBX3 might have a role in ADM. We used tamoxifen-induced Institute of Cancer research (ICR) mice to establish ADM disease model. The study procedure included western blotting and immunohistochemistry to analyze protein levels; additionally, we used intraperitoneal injection of Wnt/β-catenin pathway inhibitor XAV-939 to study the relationship between TBX3 and Wnt/β-catenin pathway as well as Anti-proliferation cell nuclear antigen( PCNA) and TUNEL to detect cell proliferation and apoptosis, respectively. TBX3 overexpression and epithelial-to-mesenchymal transition (EMT) in ADM mice was found to be associated with activation of the Wnt3a/β-catenin pathway. Treatment with XAV-939 in ADM mice led to the inhibition of both TBX3 and EMT; moreover, abnormal cell proliferation was suppressed, the depth of invasion of endometrium cells was limited. Thus, the use of XAV-939 effectively inhibited further invasion of endometrial cells.

CONCLUSION

These findings suggest that TBX3 may play an important role in the development of ADM. The expression of TBX3 in ADM was regulated by the Wnt3a/β-catenin pathway. The activation of the Wnt3a/β-catenin pathway in ADM promoted TBX3 expression and induced the occurrence of EMT, thus promoting cell proliferation and inhibiting apoptosis, ultimately accelerating the development of ADM. The study provides a reference for the diagnosis of ADM.

microRNA-944 inhibits breast cancer cell proliferation and promotes cell apoptosis by reducing SPP1 through inactivating the PI3K/Akt pathway

Breast cancer is a common malignancy in women with poor prognosis. This study aimed to investigate the molecular mechanism of microRNA-944 (miR-944) mediated secreted phosphoprotein-1 (SPP1) in breast cancer progression and its regulatory effect on the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway. Differential gene analysis was performed to identify key genes associated with breast cancer development by screening breast cancer-related microarray data. The expression of miR-944 and SPP1 and their relationship were determined in clinical samples and cells. sh-SPP1, oe-SPP1, LY294002 or miR-944 mimic were transfected into MCF-7 cells to investigate the role of miR-944 mediated SPP1 in breast cancer development and its regulatory effect on the PI3K/Akt pathway. Finally, the tumorigenicity of breast cancer cells was observed in nude mice. Through bioinformatics analysis, we identified SPP1 as a key gene in breast cancer, and miR-944 as an upstream miRNA of SPP1. In breast cancer tissues and cells, the expression of miR-944 was decreased while that of SPP1 was increased. miR-944 negatively regulated the expression of SPP1. In breast cancer cells, SPP1 activated the PI3K/Akt pathway to promote cell proliferation and inhibit apoptosis. In vitro cell experiments showed that the downregulation of miR-944 promoted the high expression of SPP1, which then activated the PI3K/Akt signaling pathway, promoting breast cancer cell proliferation. In vivo experiments further confirmed the anti-cancer role of miR-944 mediated SPP1 in breast cancer. Our study highlights the role of miR-944 mediated SPP1 in inhibiting breast cancer progression by blocking the PI3K/Akt pathway.

Heterochronic parabiosis reprograms the mouse brain transcriptome by shifting aging signatures in multiple cell types

Aging is a complex process involving transcriptomic changes associated with deterioration across multiple tissues and organs, including the brain. Recent studies using heterochronic parabiosis have shown that various aspects of aging-associated decline are modifiable or even reversible. To better understand how this occurs, we performed single-cell transcriptomic profiling of young and old mouse brains after parabiosis. For each cell type, we cataloged alterations in gene expression, molecular pathways, transcriptional networks, ligand-receptor interactions and senescence status. Our analyses identified gene signatures, demonstrating that heterochronic parabiosis regulates several hallmarks of aging in a cell-type-specific manner. Brain endothelial cells were found to be especially malleable to this intervention, exhibiting dynamic transcriptional changes that affect vascular structure and function. These findings suggest new strategies for slowing deterioration and driving regeneration in the aging brain through approaches that do not rely on disease-specific mechanisms or actions of individual circulating factors.

Secreted phosphoprotein 1 promotes angiogenesis of glioblastoma through upregulating PSMA expression via transcription factor HIF-1α

Glioblastoma multiforme (GBM) is a highly vascularized malignant brain tumor. Our previous study showed that prostate-specific membrane antigen (PSMA) promotes angiogenesis of GBM. However, the specific mechanism underlying GBM-induced PSMA upregulation remains unclear. In this study, we demonstrate that the GBM-secreted cytokine phosphoprotein 1 (SPP1) can regulate the expression of PSMA in human umbilical vein endothelial cells (HUVECs). Our mechanistic study further reveals that SPP1 regulates the expression of PSMA through the transcription factor HIF1α. Moreover, SPP1 promotes HUVEC migration and tube formation. In addition, HIF1α knockdown reduces the expression of PSMA in HUVECs and blocks the ability of SPP1 to promote HUVEC migration and tube formation. We further confirm that SPP1 is abundantly expressed in GBM, is associated with poor prognosis, and has high clinical diagnostic value with considerable sensitivity and specificity. Collectively, our findings identify that the GBM-secreted cytokine SPP1 upregulates PSMA expression in endothelial cells via the transcription factor HIF1α, providing insight into the angiogenic process and promising candidates for targeted GBM therapy.

Epigenetic Regulation of Angiogenesis in Development and Tumors Progression: Potential Implications for Cancer Treatment

Angiogenesis is a multi-stage process of new blood vessel development from pre-existing vessels toward an angiogenic stimulus. The process is essential for tissue maintenance and homeostasis during embryonic development and adult life as well as tumor growth. Under normal conditions, angiogenesis is involved in physiological processes, such as wound healing, cyclic regeneration of the endometrium, placental development and repairing certain cardiac damage, in pathological conditions, it is frequently associated with cancer development and metastasis. The control mechanisms of angiogenesis in carcinogenesis are tightly regulated at the genetic and epigenetic level. While genetic alterations are the critical part of gene silencing in cancer cells, epigenetic dysregulation can lead to repression of tumor suppressor genes or oncogene activation, becoming an important event in early development and the late stages of tumor development, as well. The global alteration of the epigenetic spectrum, which includes DNA methylation, histone modification, chromatin remodeling, microRNAs, and other chromatin components, is considered one of the hallmarks of cancer, and the efforts are concentrated on the discovery of molecular epigenetic markers that identify cancerous precursor lesions or early stage cancer. This review aims to highlight recent findings on the genetic and epigenetic changes that can occur in physiological and pathological angiogenesis and analyze current knowledge on how deregulation of epigenetic modifiers contributes to tumorigenesis and tumor maintenance. Also, we will evaluate the clinical relevance of epigenetic markers of angiogenesis and the potential use of "epi-drugs" in modulating the responsiveness of cancer cells to anticancer therapy through chemotherapy, radiotherapy, immunotherapy and hormone therapy as anti-angiogenic strategies in cancer.