Silencing of RUNX2 enhances gemcitabine sensitivity of p53-deficient human pancreatic cancer AsPC-1 cells through the stimulation of TAp63-mediated cell death

RUNX transcription factors: biological functions and implications in cancer

Runt-related transcription factors (RUNX) are a family of transcription factors that are essential for normal and malignant hematopoietic processes. Their most widely recognized role in malignancy is to promote the occurrence and development of acute myeloid leukemia. However, it is worth noting that during the last decade, studies of RUNX proteins in solid tumors have made considerable progress, suggesting that these proteins are directly involved in different stages of tumor development, including tumor initiation, progression, and invasion. RUNX proteins also play a role in tumor angiogenesis, the maintenance of tumor cell stemness, and resistance to antitumor drugs. These findings have led to the consideration of RUNX as a tumor biomarker. All RUNX proteins are involved in the occurrence and development of solid tumors, but the role of each RUNX protein in different tumors and the major signaling pathways involved are complicated by tumor heterogeneity and the interacting tumor microenvironment. Understanding how the dysregulation of RUNX in tumors affects normal biological processes is important to elucidate the molecular mechanisms by which RUNX affects malignant tumors.

Knockdown of long non-coding RNA CCAT1 suppresses proliferation and EMT of human cervical cancer cell lines by down-regulating Runx2

BACKGROUND

Cervical cancer (CC) is one of the common malignant tumors in women. CCAT1 is a novel lncRNA and its knockdown can inhibit viability, migration and invasion in CC cells. Here, we aimed to further explore the roles of CCAT1 knockdown and underlying mechanism to provide theoretical support for the application of CCAT1 knockdown in treating CC.

METHODS

The expression level of CCAT1 in CC tissues was examined by using qRT-PCR. Si-CCAT1, pc-Runx2 and relative control were transfected into HeLa and SiHa cells to explore the functional mechanism of CCAT1. The effects of CCAT1 on cell proliferation, apoptosis, migration and invasion were examined via BrdU incorporation assay, flow cytometry and transwell assay. The expression of Runx2 and other relative factors was examined via qRT-PCR and western blot analysis.

RESULTS

Our findings indicated that CCAT1 was highly expressed in CC tissues contrasted with adjacent tissues. The proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) were suppressed, while the apoptosis was promoted by CCAT1 knockdown. Moreover, knockdown of CCAT1 could negatively regulate Runx2 to play anti-tumor roles in HeLa and SiHa cells. Further, CCAT1 knockdown could suppress PI3K/AKT signal pathway.

CONCLUSION

Knockdown of CCAT1 suppressed proliferation, EMT, migration and invasion in HeLa and SiHa cells through down-regulating Runx2, which provided theoretical support for its application in CC treatment.

Identification of genes and genetic networks associated with BAG3‑dependent cell proliferation and cell survival in human cervical cancer HeLa cells

Bcl‑2‑associated athanogene (BAG) 3, is a member of the BAG protein family and a known co‑chaperone of heat shock protein (HSP) 70. BAG3 serves a role in regulating a variety of cellular functions, including cell growth, proliferation and cell death including apoptosis. BAG3 is a stress‑inducible protein, however the constitutive expression level of BAG3 is increased in cancer cells compared with healthy cells. Recent proteomics technology combined with bioinformatics has revealed that BAG3 participates in an interactome with a number of proteins other than its typical partner HSP70. The functional types represented in the interactome included nucleic acid binding proteins and transcription factors, as well as chaperones, which indicated that overexpression of BAG3 may contribute to proliferation and cell survival through the alteration of gene transcription. While an increasing number of studies have addressed the function of BAG3 as a co‑chaperone protein, BAG3‑dependent alteration of gene transcription has not been studied extensively. The present study established two BAG3 knockout human cervical cancer HeLa cell clones and addressed the role of BAG3 in cell proliferation and survival through gene transcription, using DNA microarray‑based transcriptome analysis and bioinformatics. The present study also identified two genetic networks associated with 'cellular growth and proliferation' and 'cell death and survival', which are dysregulated in the absence of BAG3, and may therefore be linked to BAG3 overexpression in cancer. These findings provide a molecular basis for understanding of BAG3‑dependent cell proliferation and survival from the aspect of alteration of gene expression.

ERO1L promotes pancreatic cancer cell progression through activating the Wnt/catenin pathway

Pancreatic cancer is a lethal malignancy with an extremely poor prognosis. Although many genes and noncoding RNAs have been found to regulate its progression, more regulators are needed to be understood to resolve its high lethality. Endoplasmic reticulum oxidoreductase 1 alpha (ERO1L) plays crucial roles in the progression of various tumors, but its role in pancreatic cancer progression has not been studied. In this study, we found that ERO1L was significantly upregulated in pancreatic cancer cells and patients; its overexpression significantly promoted pancreatic cancer migration, invasion, and growth, while its knockdown significantly inhibited pancreatic cancer migration, invasion, and growth. Mechanism analysis suggested that ERO1L promoted many tumor-associated signaling pathways, especially the Wnt/catenin pathway; it could activate the Wnt/catenin pathway and upregulate the targets of the Wnt/catenin pathway. We further analyzed the correlation between ERO1L expression and the prognosis of patients, suggesting that patients with high ERO1L expression had short survival time; it is an independent prognosis factor for patients' prognosis. Together, we found that ERO1L was an oncogene for pancreatic cancer.

The p53 Family in Brain Disease

SIGNIFICANCE

The p53 family of transcription factors, including p53, p63, and p73, plays key roles in both biological and pathological processes, including cancer and neural development. Recent Advances: In recent years, a growing body of evidence has indicated that the entire p53 family is involved in the regulation of the central nervous system (CNS) functions as well as in the pathogenesis of several neurological disorders. Mechanistically, the p53 proteins control neuronal cell fate, terminal differentiation, and survival, via a complex interplay among the family members.

CRITICAL ISSUES

In this article, we discuss the involvement of the p53 family in neurobiology and in pathological conditions affecting the CNS, including neuroinflammation.

FUTURE DIRECTIONS

Understanding the molecular mechanism(s) underlying the function of the p53 family could improve our general knowledge of the pathogenesis of brain disorders and potentially pave the road for new therapeutic intervention. Antioxid. Redox Signal. 29, 1-14.

miR-3656 expression enhances the chemosensitivity of pancreatic cancer to gemcitabine through modulation of the RHOF/EMT axis

The highly refractory nature of pancreatic cancer (PC) to chemotherapeutic drugs is one of the key reasons contributing to the poor prognosis of this disease. MicroRNAs (miRNAs) are key regulators of gene expression and have been implicated in a variety of processes from cancer development through to drug resistance. Herein, through miRNA profiling of gemcitabine-resistant (GR) and parental PANC-1 cell lines, we found a consistent reduction of miR-3656 in GR PANC-1 cells. miR-3656 overexpression enhanced the antitumor effect of gemcitabine, whereas silencing of miR-3656 resulted in the opposite effect. By performing mechanistic studies using both in vitro and in vivo models, we found that miR-3656 could target RHOF, a member of the Rho subfamily of small GTPases, and regulate the EMT process. Moreover, enforced EMT progression via TWIST1 overexpression compromised the chemotherapy-enhancing effects of miR-3656. Finally, we found significantly lower levels of miR-3656 and higher levels of RHOF in PC tissues compared with adjacent noncancerous pancreatic tissues, and this was also associated with poor PC patients’ prognosis. Taken together, our results suggest that the miR-3656/RHOF/EMT axis is an important factor involved in regulating GR in PC, and highlights the potential of novel miR-3656-based clinical modalities as a therapeutic approach in PC patients.

Long non-coding RNA SNHG1 regulates zinc finger E-box binding homeobox 1 expression by interacting with TAp63 and promotes cell metastasis and invasion in Lung squamous cell carcinoma

The long non-coding RNAs (lncRNAs) have been recently shown to participate in the progression of a variety of cancers. However, the biological role of lncRNAs and the underlying mechanisms in Lung squamous cell carcinoma (SCC) or lung adenocarcinoma (AD) remain unclear. Herein, we investigated expression of 5 lncRNAS (SNHG1, NCBP2-AS2, LINC01206, SOX2-OT and LINC01419) in SCC and AD tissues. SNHG1 was one of over-expressed lncRNAs in SCC tissues. Knockdown of SNHG1 significantly inhibited the proliferation, metastasis, invasive ability and induced apoptosis of SCC cells. Moreover, SNHG1 affected the expression of zinc finger E-box binding homeobox 1(ZEB1), which has also been observed to be up-regulated in SCC and to promote cell metastasis and invasion. Rather than direct interaction, SNHG1 regulated ZEB1expression by suppressing the activity of p63 TA isoform (TAp63), which is a repressor of ZEB1 and physically associates with SNHG1. Furthermore, SNHG1 promoted ZEB1 expression and promoted cell proliferation, metastasis, invasive but inhibited apoptosis of SCC cells via the TAp63/ZEB1 pathway. Taken together, our findings suggested that SNHG1 might play an oncogenic role in SCC through ZEB1 signaling pathway by inhibiting TAp63 and might serve as a valuable prognostic biomarker and therapeutic target for SCC patients.

RUNX2 promotes hepatocellular carcinoma cell migration and invasion by upregulating MMP9 expression

Runt-related transcription factor 2 (RUNX2) was first identified as a transcription factor to play an important role in different biological processes of osteoblast and chondrocyte, including differentiation and migration. Recently, RUNX2 has been implicated in promigratory/proinvasive behavior in different human malignancies. In the present study, we demonstrated that the RUNX2 mRNA and protein expression were both increased significantly in HCC tissues and cell lines. High RUNX2 expression was correlated obviously with poor clinicopathological characteristics including multiple tumor nodes, high histological grading, venous infiltration and advanced tumor-node-metastasis (TNM) stage. In addition, we demonstrated that RUNX2 was a prognostic indicator for predicting 5-year overall survival and disease-free survival of HCC patients. Our studies showed that RUXN2 overexpression promoted, while RUNX2 knockdown inhibited HCC cell migration and invasion in vitro. Notably, RUNX2 positively regulated matrix metalloproteinase 9 (MMP9) accumulation in HCC cells. Furthermore, we confirmed that RUNX2 was positively correlated with MMP9 expression in HCC tissues by Pearson correlation analysis. Mechanistically, we demonstrated that MMP9 overexpression increased HCC cell migration and invasion, while MMP9 knockdown reduced HCC cell migration and invasion in vitro. Alteration of MMP9 expression partially abrogated the effects of RUNX2 on HCC cell migration and invasion, which suggests that RUNX2 developed its pro-metastatic biological function by upregulating the expression of MMP9 in HCC cells. In conclusion, our results reveal that RUNX2 promotes HCC cell migration and invasion by MMP9-mediated pathway, and potentially serves as a new prognostic biomarker and in therapeutic strategies for HCC.