Knockdown of KIAA1199 attenuates growth and metastasis of hepatocellular carcinoma

CEMIP (HYBID, KIAA1199): structure, function and expression in health and disease

CEMIP (cell migration-inducing protein), also known as KIAA1199 or HYBID, is a protein involved in the depolymerisation of hyaluronic acid (HA), a major glycosaminoglycan component of the extracellular matrix. CEMIP was originally described in patients affected by nonsyndromic hearing loss and has subsequently been shown to play a key role in tumour initiation and progression, as well as arthritis, atherosclerosis and idiopathic pulmonary fibrosis. Despite the vast literature associating CEMIP with these diseases, its biology remains elusive. The present review article summarises all the major scientific evidence regarding its structure, function, role and expression, and attempts to cast light on a protein that modulates EMT, fibrosis and tissue inflammation, an unmet key aspect in several inflammatory disease conditions.

KIAA1199 deficiency enhances skeletal stem cell differentiation to osteoblasts and promotes bone regeneration

Upon transplantation, skeletal stem cells (also known as bone marrow stromal or mesenchymal stem cells) can regulate bone regeneration by producing secreted factors. Here, we identify KIAA1199 as a bone marrow stromal cell-secreted factor in vitro and in vivo. KIAA1199 plasma levels of patients positively correlate with osteoporotic fracture risk and expression levels of KIAA1199 in patient bone marrow stromal cells negatively correlates with their osteogenic differentiation potential. KIAA1199-deficient bone marrow stromal cells exhibit enhanced osteoblast differentiation in vitro and ectopic bone formation in vivo. Consistently, KIAA1199 knockout mice display increased bone mass and biomechanical strength, as well as an increased bone formation rate. They also exhibit accelerated healing of surgically generated bone defects and are protected from ovariectomy-induced bone loss. Mechanistically, KIAA1199 regulates osteogenesis by inhibiting the production of osteopontin by osteoblasts, via integrin-mediated AKT and ERK-MAPK intracellular signaling. Thus, KIAA1199 is a regulator of osteoblast differentiation and bone regeneration and could be targeted for the treatment or management of low bone mass conditions.

Downregulation of CEMIP enhances radiosensitivity by promoting DNA damage and apoptosis in colorectal cancer

Colorectal cancer (CRC) is the third leading malignancy worldwide in both new cases and deaths. Neoadjuvant radiotherapy is the standard preoperative regimens for locally advanced patients. However, approximately 50% of patients develop recurrence and metastasis after radiotherapy, which is largely due to the radiation resistance properties of the tumor, and the internal mechanism has not been elucidated. Here we found that CEMIP expression is up-regulated in a variety of tumor types, particularly in CRC. Public databases and clinical samples revealed that CEMIP expression is significantly higher in tumor tissues than in adjacent normal tissues in patients with locally advanced CRC who received neoadjuvant chemoradiotherapy, and it is closely related to the poor prognosis. Functional characterization uncovered that downregulation of CEMIP expression can enhance the radiosensitivity of CRC cells, which is confirmed to be achieved by promoting DNA damage and apoptosis. In vivo studies further verified that CEMIP knockdown can significantly improve the radiosensitivity of subcutaneously implanted colorectal tumors in mice, suggesting that CEMIP may be a radiation-resistant gene in CRC. Mechanistically, EGFR/PI3K/Akt signaling pathway is hypothesized to play a key role in CEMIP mediating radiation resistance. These results provide a potential new strategy targeting CEMIP gene for the comprehensive treatment of locally advanced CRC patients.

Downregulation of KIAA1199 alleviated the activation, proliferation, and migration of hepatic stellate cells by the inhibition of epithelial-mesenchymal transition

KIAA1199, a major glycosaminoglycan component of the extracellular matrix, was reported to induce a fibrosis-like process. However, the relationship between KIAA1199 and liver fibrosis remains unclear. The liver fibrosis mouse model was established with carbon tetrachloride (CCl₄). Here, we found that KIAA1199 was upregulated in CCl₄-induced liver fibrosis. The expression of KIAA1199 was also increased in TGF-β-stimulated LX-2 cells. To clarify the impact of KIAA1199 in hepatic stellate cells (HSCs), we downregulated the expression of KIAA1199 in LX-2 cells by RNA interference. Cell proliferation, apoptosis, and migration were determined by CCK-8, flow cytometry, and transwell assay. We found that KIAA1199 knockdown reduced the expression of fibrosis markers α-SMA and COL1A1. Depletion of KIAA1199 inhibited cell proliferation by downregulating cyclin B1 and cyclin D1 and promoted cell apoptosis by upregulating Bax and downregulating Bcl-2. Moreover, KIAA1199 knockdown decreased matrix metalloproteinase-2 (MMP-2) and MMP-9 expression to inhibit the migration ability of LX-2 cells. Silencing KIAA1199 also suppressed the epithelial-mesenchymal transition phenomenon. Collectively, our study revealed that KIAA1199 knockdown alleviated the activation, proliferation, and migration of HSCs, while promoting apoptosis of HSCs, which suggests that KIAA1199 may be a potential regulator of liver fibrosis.

CEMIP, a Promising Biomarker That Promotes the Progression and Metastasis of Colorectal and Other Types of Cancer

Simple Summary

CEMIP (cell migration-inducing and hyaluronan-binding protein) has been implicated in the pathogenesis of numerous diseases, including colorectal and other forms of cancer. The molecular functions of CEMIP are currently under investigation and include the degradation of the extracellular matrix component hyaluronic acid (HA), as well as the regulation of a number of signaling pathways. In this review, we survey our current understanding of how CEMIP contributes to tumor growth and metastasis, focusing particularly on colorectal cancer, for which it serves as a promising biomarker.

Abstract

Originally discovered as a hypothetical protein with unknown function, CEMIP (cell migration-inducing and hyaluronan-binding protein) has been implicated in the pathogenesis of numerous diseases, including deafness, arthritis, atherosclerosis, idiopathic pulmonary fibrosis, and cancer. Although a comprehensive definition of its molecular functions is still in progress, major functions ascribed to CEMIP include the depolymerization of the extracellular matrix component hyaluronic acid (HA) and the regulation of a number of signaling pathways. CEMIP is a promising biomarker for colorectal cancer. Its expression is associated with poor prognosis for patients suffering from colorectal and other types of cancer and functionally contributes to tumor progression and metastasis. Here, we review our current understanding of how CEMIP is able to foster the process of tumor growth and metastasis, focusing particularly on colorectal cancer. Studies in cancer cells suggest that CEMIP exerts its pro-tumorigenic and pro-metastatic activities through stimulating migration and invasion, suppressing cell death and promoting survival, degrading HA, regulating pro-metastatic signaling pathways, inducing the epithelial–mesenchymal transition (EMT) program, and contributing to the metabolic reprogramming and pre-metastatic conditioning of future metastatic microenvironments. There is also increasing evidence indicating that CEMIP may be expressed in cells within the tumor microenvironment that promote tumorigenesis and metastasis formation, although this remains in an early stage of investigation. CEMIP expression and activity can be therapeutically targeted at a number of levels, and preliminary findings in animal models show encouraging results in terms of reduced tumor growth and metastasis, as well as combating therapy resistance. Taken together, CEMIP represents an exciting new player in the progression of colorectal and other types of cancer that holds promise as a therapeutic target and biomarker.

Endoplasmic reticulum-resident protein Sec62 drives colorectal cancer metastasis via MAPK/ATF2/UCA1 axis

OBJECTIVE

Metastasis is responsible for the poor prognosis of patients with colorectal cancer (CRC), and the role of aberrant expression of endoplasmic reticulum (ER) receptors in tumour metastasis has not been fully elucidated. The aim of the study is to ensure the role of ER-resident protein Sec62 in CRC metastasis and illuminate associated molecular mechanisms.

MATERIALS AND METHODS

Bioinformatics analysis, qRT-PCR, western blot and immunohistochemistry assays were performed to evaluate the expression level and clinical significance of Sec62 in CRC. The specific role of Sec62 in CRC was identified by a series of functional experiments. We conducted RNA sequencing and rescue experiments to analyse the differentially expressed genes and identified UCA1 as a novel pro-metastasis target of Sec62 in CRC. Besides, the efficacy of MAPK/JNK inhibitor or agonist on Sec62-mediated CRC metastasis was evaluated by trans-well and wound healing assays. Finally, luciferase reporter and ChIP assay were employed to further explore the potential mechanisms.

RESULTS

The abnormally elevated expression of Sec62 predicted poor prognosis of CRC patients and facilitated malignant metastasis of CRC cells. Mechanistically, Sec62 enhanced UCA1 expression through activating MAPK/JNK signalling pathway. And the p-JNK activating ATF2 could transcriptionally regulate UCA1 expression. Furthermore, blocking or activating MAPK/JNK signalling with JNK inhibitor or agonist potently suppressed or enhanced Sec62 mediated CRC metastatic process.

CONCLUSIONS

Our study reports for the first time that the Sec62/MAPK/ATF2 /UCA1 axis exists in CRC metastatic process, which could be a potential treatment target of metastatic CRC.

CEMIP as a potential biomarker and therapeutic target for breast cancer patients

Purpose: We aimed to evaluate whether CEMIP plays any role in the survival outcome of breast cancer (BC) patients, as well as to explore the regulatory mechanism of CEMIP in BC. Methods: We evaluated the expression and prognostic effect of CEMIP in BC patients using the Oncomine, GEPIA, UALCAN, and Kaplan-Meier plotter databases. Additionally, we detected CEMIP mRNA and protein levels in BC and normal tissues via PCR and western blotting analyses. Through immunochemistry analysis, we quantified CEMIP expression in 233 samples from BC patients. We then analyzed the link between the survival outcomes and CEMIP expression based on these clinical samples. Furthermore, we explored the immune-related molecules regulated by CEMIP and its coexpressed genes using the STRING database. Results: CEMIP expression was higher in BC tissues than in normal tissues. Patients with high CEMIP mRNA levels had a worse survival outcome. Similarly, patients expressing CEMIP had significantly shorter overall survival and disease-free survival than those not expressing the protein (P < 0.01). Some lymphocytes, immune inhibitors, immune stimulators, MHC molecules, chemokines, and chemokine receptors can be regulated by CEMIP, and CEMIP and its coexpressed genes can participate in the hyaluronan biosynthetic process, hyaluronan catabolic process, and other related biological processes in the progression of BC. Conclusion: Compared to normal tissues, BC tissues had higher number of CEMIP transcripts. CEMIP expression was associated with an adverse prognosis. CEMIP and its coexpressed genes can participate in the progression of BC. Therefore, CEMIP may be a potential biomarker for the treatment of BC patients.

The emerging role of KIAA1199 in cancer development and therapy

KIAA1199, also known as CEMIP or HYBID, is an important member of the Human Unidentified Gene-Encoded (HUGE) database. Accumulated evidence has revealed that KIAA1199 is associated with tumor progression and metastasis in numerous malignancies, including colorectal, liver, gastric, pancreatic, breast, lung, prostate, ovarian and papillary thyroid cancers. As an oncogene, it plays crucial role in the proliferation, apoptosis, invasion and migration of various tumor cells. In addition, KIAA1199 is also involved in the regulation of multiple signal pathways such as epithelial-mesenchymal transition (EMT), Wnt/ β-catenin, MEK/ERK and PI3K/Akt. In this review, we summarized up to date advancement on the role of KIAA1199 in human cancer development, progression, and metastasis. We also addressed KIAA1199 as a potential therapeutic target for cancer therapy.

Co-expression of KIAA1199 and hypoxia-inducible factor 1α is a biomarker for an unfavorable prognosis in hepatocellular carcinoma

Advanced studies demonstrated that hypoxic stress induced KIAA1199 expression leading to enhanced cell migration. KIAA1199 is a protein related with cancer metastasis. Hypoxia inducible factor 1α (HIF-1α) is a transcriptional factor that maintains oxygen homeostasis. Both KIAA1199 and HIF-1α were upregulated in many human cancers. In the present study, co-expression of KIAA1199 and HIF-1α was evaluated for the clinicopathological characteristics and survival in hepatocellular carcinoma (HCC). Clinical-pathological information and follow-up data were collected from 152 HCC patients. KIAA1199 and HIF-1α expression were scored based on the percentage and intensity of immunohistochemical staining in pathological slide. Correlations between clinical features and the expression of KIAA1199 and HIF-1α were evaluated by Chi-square test, Kaplan-Meier curves and multivariate Cox regression analysis. The frequency of KIAA1199 high expression was higher in HCC than adjacent tissue. KIAA1199(H)/HIF-1α(H) tumors were more frequently of TNM (P = .011), tumor size (P = .021), vascular invasion (P = .002) and HBV (P = .001). In survival analysis, KIAA1199(H)/HIF-1α(H) patients had the worst prognosis. Using the combination of the two parameters increased the prognostic value (P < .01 vs P = .03). KIAA1199 in combination with HIF-1α expression tends to indicate a more accurate prognosis.

Downregulation of KIAA1199 by miR-486-5p suppresses tumorigenesis in lung cancer

Lung cancer is the primary cause of death among cancer patients in China, among which nonsmall cell lung cancer (NSCLC) makes up the great majority. Hence, it is imperative to identify the biomarkers and mechanisms involved in NSCLC oncogenesis. Our present research found that KIAA1199 expression was significantly increased in NSCLC and closely related to cell proliferation, motility, and poor prognosis. We demonstrated that knockdown of KIAA1199 reduced NSCLC cell growth and motility in vitro whereas overexpression of KIAA1199 had the opposite effect. Inhibition of KIAA1199 significantly suppressed tumor growth in mouse NSCLC xenograft models. Mechanistically, as an epidermal growth factor receptor (EGFR)‐binding protein, KIAA1199 promotes EGFR signaling and regulates EGFR‐dependent Src, Erk, and Akt phosphorylation, as well as downstream kinases in the EGF‐mediated EMT pathway. We demonstrated that KIAA1199 can function as a direct binding target for miR‐486‐5p and that miR‐486‐5p overexpression can attenuate proliferation and migration of NSCLC cells via regulating the EGFR signaling pathways. To conclude, our results defined KIAA1199 as an oncogenic protein that promotes cancer cell proliferation and migration by regulating EGF‐mediated signaling pathways. This study provided new insight into NSCLC oncogenesis, which could lead to the development of innovative therapeutic plans for NSCLC.

miR‑296‑3p promotes the proliferation of glioblastoma cells by targeting ICAT

MicroRNAs (miRNA/miRs) serve an important function in the regulation of gene expression, and have been indicated to mediate a number of cellular biological processes, including cell proliferation, the cell cycle, cell apoptosis and cell differentiation. The altered expression of miRNAs has been revealed to result in a variety of human diseases, including glioblastoma multiforme (GBM). The present study indicated an increase in miR‑296‑3p in glioma tumor types compared with normal brain, particularly in the samples from patients with high grade GBM. Antagonizing miR‑296‑3p was demonstrated to induce cell growth arrest and cell cycle redistribution in U251 cells. The miR‑296‑3p antagonist altered the expression of a number of key genes that are involved in cell cycle control, including cyclin D1 and p21. Additionally, the decrease of miR‑296‑3p increased inhibitor of β‑catenin and T cell factor (ICAT) expression, and increased miR‑296‑3p‑inhibited ICAT expression in U251 cells. Bioinformatics analysis indicated that ICAT is a target gene of miR‑296‑3p, which was further validated using a dual‑luciferase reporter assay. Through the regulation of ICAT, the miR‑296‑3p antagonist decreased β‑catenin protein expression and increased the expression of its target genes. Silencing ICAT was indicated to reverse the miR‑296‑3p downregulation‑induced inactivation of Wnt signaling and cell growth arrest in glioma cells. The present study also indicated a negative correlation between ICAT mRNA levels and miR‑296‑3p levels in glioma tumor types. In conclusion, the present study identified an oncogenic function of miR‑296‑3p in glioblastoma via the direct regulation of ICAT.

KIAA1199 promotes sorafenib tolerance and the metastasis of hepatocellular carcinoma by activating the EGF/EGFR-dependent epithelial-mesenchymal transition program

Patients with advanced hepatocellular carcinoma (HCC) will almost always develop acquired tolerance after sorafenib therapy, and the molecular mechanism of sorafenib tolerance remains poorly characterized. Here, using our established sorafenib-resistant HCC cell and xenograft models, we identified a novel gene, KIAA1199, which was markedly elevated among the differentially expressed genes involved in sorafenib tolerance. Moreover, elevated expression of KIAA1199 was positively correlated with a high risk of recurrence and metastasis and advanced TNM stage in HCC patients. Functionally, loss- and gain-of-function studies showed that KIAA1199 promoted the migration, invasion, and metastasis of sorafenib-resistant HCC cells. Mechanistically, KIAA1199 is required for EGF-induced epithelial-mesenchymal transition (EMT) in sorafenib-resistant HCC cells by aiding in EGFR phosphorylation. In summary, our data uncover KIAA1199 as a novel sorafenib-tolerant promoting gene that plays an indispensable role in maintaining sorafenib-resistant HCC cell metastasis.