INPP5F translocates into cytoplasm and interacts with ASPH to promote tumor growth in hepatocellular carcinoma

Background Increasing evidence has suggested inositol polyphosphate 5-phosphatase family contributes to tumorigenesis and tumor progression. However, the role of INPP5F in hepatocellular carcinoma (HCC) and its underlying mechanisms is unclear. Methods The expression of INPP5F in HCC was analyzed in public databases and our clinical specimens. The biological functions of INPP5F were investigated in vitro and vivo. The molecular mechanism of INPP5F in regulating tumor growth were studied by transcriptome-sequencing analysis, mass spectrometry analysis, immunoprecipitation assay and immunofluorescence assay. Results High expression of INPP5F was found in HCC tissues and was associated with poor prognosis in HCC patients. Overexpression of INPP5F promoted HCC cell proliferation, and vice versa. Knockdown of INPP5F suppressed tumor growth in vivo. Results from transcriptome-sequencing analysis showed INPP5F not only regulated a series of cell cycle related genes expression (c-MYC and cyclin E1), but also promoted many aerobic glycolysis related genes expression. Further studies confirmed that INPP5F could enhance lactate production and glucose consumption in HCC cell. Mechanistically, INPP5F activated Notch signaling pathway and upregulated c-MYC and cyclin E1 in HCC via interacting with ASPH. Interestingly, INPP5F was commonly nuclear-located in cells of adjacent non-tumor tissues, while in HCC, cytoplasm-located was more common. LMB (nuclear export inhibitor) treatment restricted INPP5F in nucleus and was associated with inhibition of Notch signaling and cell proliferation. Sequence of nuclear localization signals (NLSs) and nuclear export signals (NESs) in INPP5F aminoacidic sequence were then identified. Alteration of the NLSs or NESs influenced the localization of INPP5F and the expression of its downstream molecules. Furthermore, we found INPP5F interacted with both exportin and importin through NESs and NLSs, respectively, but the interaction with exportin was stronger, leading to cytoplasmic localization of INPP5F in HCC. Conclusion These findings indicate that INPP5F functions as an oncogene in HCC via a translocation mechanism and activating ASPH-mediated Notch signaling pathway. INPP5F may serve as a potential therapeutic target for HCC patients.

Baicalein Attenuates Hepatocellular Carcinoma Cell Survival and Induces Apoptosis Through the miR‑3178/HDAC10 pathway

Hepatocellular carcinoma (HCC) is the most common type of hepatic malignancies with high mortality and poor prognosis and is the third most common cause of malignancies death worldwide which is more than 700,000 deaths per year. Baicalein, one of the major and bioactive flavonoid isolated from Scutellaria baicalensis Georgi, which is reported to have anti-proliferation effect in varying cancers, including HCC, whose underlying molecular mechanism is still largely unknown. In this study, the results showed that administration of baicalein significantly inhibited proliferation and colony formation, blocked cell cycle arrest at the S phase, and promoted apoptosis in HCC cells MHCC-97H and SMMC-7721 in vitro and reduced HCC tumor volume and weight in vivo. Increased microRNA (miR)‑3178 levels and decreased histone deacetylase 10 (HDAC10) expression were found in cells treated with baicalein and in patients’ HCC tissues. HDAC10 was identified as a target gene of miR‑3178 by luciferase activity and western blot. Both baicalein treatment and overexpression of miR-3178 could down-regulate protein expression of HDAC10 and inactivated AKT, MDM2/p53/Bcl2/Bax and FoxO3α/p27/CDK2/Cyclin E1 signal pathways. Not only that, knockdown of miR‑3178 could partly abolish the effects of baicalein and the restoration of HDAC10 could abated miR-3178-mediated role in HCC cells. Collectively, baicalein inhibited cell viability, blocks cell cycle and induces apoptosis in HCC cells by regulating the miR‑3178/HDAC10 pathway. This finding indicated that baicalein might be promising for treatment of HCC.

Anti-Psoriatic Effects and IL-22 Targeting Mechanism of Indirubin by Suppressing Keratinocyte Inflammation and Proliferation

Indigo naturalis, which is extracted from the leaves and branches of Baphicacanthus cusia (Nees) Bremek, has traditionally been used to treat psoriasis. The current study aimed to examine a new mechanism of the components of indigo naturalis, including indirubin, indigo, and tryptanthrin. The anti-psoriatic effects were assessed by the proliferation biomarkers (Ki67, K16), cell cycle progression, ROS production, and interleukin profiling (ICAM-1, TNF-α, IL-6, and IL-8) in IL-22-treated HaCaT cells. Among the components, indirubin significantly decreased intracellular ROS production and lowered the production of ICAM-1, TNF-α, and IL-6 in IL-22-treated HaCaT cells. Indirubin, indigo, and tryptanthrin could decrease the proportion of Ki67-positive cells, but only indirubin decreased the proportion of cells entering the S phase and suppressed the expression of cyclin D1 and cyclin E1 in IL-22-treated HaCaT cells. Indirubin significantly suppressed the phosphorylation of STAT3 and ERK. In vivo, IL-22 was intradermally injected into mouse ears for six days and topically treated with 0.1% or 1% indirubin. In the IL-22-injected mice, treatment with indirubin inhibited epidermal hyperplasia. Immunohistochemistry and western blot analysis demonstrated the downregulation of K16 expression in psoriatic lesions. These results suggest that indirubin, which is a major component of indigo naturalis, may have therapeutic potential in an IL-22-induced psoriasis model.

Fumonisin B1 Inhibits Cell Proliferation and Decreases Barrier Function of Swine Umbilical Vein Endothelial Cells

The fumonisins are a group of common mycotoxins found around the world that mainly contaminate maize. As environmental toxins, they pose a threat to human and animal health. Fumonisin B1 (FB1) is the most widely distributed and the most toxic. FB1 can cause pulmonary edema in pigs. However, the current toxicity mechanism of fumonisins is still in the exploratory stage, which may be related to sphingolipid metabolism. Our study is designed to investigate the effect of FB1 on the cell proliferation and barrier function of swine umbilical vein endothelial cells (SUVECs). We show that FB1 can inhibit the cell viability of SUVECs. FB1 prevents cells from entering the S phase from the G1 phase by regulating the expression of the cell cycle-related genes cyclin B1, cyclin D1, cyclin E1, Cdc25c, and the cyclin-dependent kinase-4 (CDK-4). This results in an inhibition of cell proliferation. In addition, FB1 can also change the cell morphology, increase paracellular permeability, destroy tight junctions and the cytoskeleton, and reduce the expression of tight junction-related genes Claudin 1, Occludin, and ZO-1. This indicates that FB1 can cause cell barrier dysfunction of SUVECs and promote the weakening or even destruction of the connections between endothelial cells. In turn, this leads to increased blood vessel permeability and promotes exudation. Our findings suggest that FB1 induces toxicity in SUVECs by affecting cell proliferation and disrupting the barrier function.

Cyclin E/CDK2: DNA Replication, Replication Stress and Genomic Instability

DNA replication must be precisely controlled in order to maintain genome stability. Transition through cell cycle phases is regulated by a family of Cyclin-Dependent Kinases (CDKs) in association with respective cyclin regulatory subunits. In normal cell cycles, E-type cyclins (Cyclin E1 and Cyclin E2, CCNE1 and CCNE2 genes) associate with CDK2 to promote G1/S transition. Cyclin E/CDK2 complex mostly controls cell cycle progression and DNA replication through phosphorylation of specific substrates. Oncogenic activation of Cyclin E/CDK2 complex impairs normal DNA replication, causing replication stress and DNA damage. As a consequence, Cyclin E/CDK2-induced replication stress leads to genomic instability and contributes to human carcinogenesis. In this review, we focus on the main functions of Cyclin E/CDK2 complex in normal DNA replication and the molecular mechanisms by which oncogenic activation of Cyclin E/CDK2 causes replication stress and genomic instability in human cancer.

Fractionated Radiation Exposure Enhances DNA Repair Capacity to Amplify Radioresistance of Cancer Cells

Fractionated radiotherapy is widely used in cancer therapy for its advantages in the preservation of normal tissues, but may amplify radioresistance of cancer cells. To understand whether and how fractionated radiation exposure amplifies radioresistance, HCT-8 human colon cancer cells and MCF-7 human breast cancer cells were received a total dose of 5 Gy X-ray irradiation by a single exposure or fractionated exposures (1 Gy/day for 5 consecutive days), respectively. We then examined the radioresistance of cells. Underwent an additional exposing to 2 Gy, cells received fractionated exposures showed significantly better cell proliferation and clonogenic ability than cells received a single exposure. Compared to the intact cells without radiation exposure, the expression of γ-H2AX, pATM and PARP was significantly enhanced in only these cells received fractionated exposures. However, the expression of cyclin D1 and cyclin E1 was enhanced in only these HCT-8 cells received a single exposure. Otherwise, the expression of SOD1, SOD2 and caspase 3 was not significantly changed in both cells received either a single exposure or fractionated exposures. Fractionated radiation exposure amplifies radioresistance of cancer cells, predominantly by enhancing DNA repair capacity.

CCNE1 promotes progression and is associated with poor prognosis in lung adenocarcinoma

Background : Mounting evidence has shown that Cyclin E1 (CCNE1) facilitates various carcinoma progression, but its function in lung adenocarcinoma (LUAD) remains unclear. Objective: Our study aims to explore the significance of CCNE1 in clinical progression and study its biological functions in LUAD. Methods: CCNE1 expressions in LUAD specimens and cells were detected through quantitative realtime polymerase chain reaction (qRT-RCR) and western blot. An immunohistochemistry technique was used to detect CCNE1 expression to explore its association with clinical parameters. The LUAD cells with stable knockdown of CCNE1 were constructed by small interfering RNA. The effect of CCNE1 on LUAD cells proliferation and apoptosis was evaluated through Cell Counting Kit-8 (CCK-8), colony formation, and Annexin V/propidium iodide (AV-PI) assays, respectively. The cell migration and invasion were evaluated by Wound-healing and Transwell assays, respectively. The xenograft and lung metastasis mouse models were introduced to analyze how CCNE1 knockdown affects tumor growth and tumor metastasis. Results: CCNE1 expression was upregulated in LUAD tissue and cells. CCNE1 knockdown inhibited LUAD cellular malignant behavior in vitro and reduced tumor growth and metastasis in vivo. High expression of CCNE1 was correlated with big tumor size, cancer stage, lymph node metastasis, and poor prognosis. Conclusions: CCNE1 overexpression promotes LUAD growth, metastasis, and forebode poor prognosis: it can serve as a new prognostic marker of LUAD.

Cyclin E1 in Murine and Human Liver Cancer: A Promising Target for Therapeutic Intervention during Tumour Progression

Cyclin E1 (CCNE1) is a regulatory subunit of Cyclin-dependent kinase 2 (CDK2) and is thought to control the transition of quiescent cells into cell cycle progression. Recently, we identified CCNE1 and CDK2 as key factors for the initiation of hepatocellular carcinoma (HCC). In the present study, we dissected the contributions of CCNE1 and CDK2 for HCC progression in mice and patients. Therefore, we generated genetically modified mice allowing inducible deletion of Ccne1 or Cdk2. After initiation of HCC, using the hepatocarcinogen diethylnitrosamine (DEN), we deleted Ccne1 or Cdk2 and subsequently analysed HCC progression. The relevance of CCNE1 or CDK2 for human HCC progression was investigated by in silico database analysis. Interventional deletion of Ccne1, but not of Cdk2, substantially reduced the HCC burden in mice. Ccne1-deficient HCCs were characterised by attenuated proliferation, impaired DNA damage response and downregulation of markers for stemness and microinvasion. Additionally, the tumour microenvironment of Ccne1-deficient mice showed a reduction in immune mediators, myeloid cells and cancer-associated fibroblasts. In sharp contrast, Cdk2 was dispensable for HCC progression in mice. In agreement with our mouse data, CCNE1 was overexpressed in HCC patients independent of risk factors, and associated with reduced disease-free survival, a common signature for enhanced chromosomal instability, proliferation, dedifferentiation and invasion. However, CDK2 lacked diagnostic or prognostic value in HCC patients. In summary, CCNE1 drives HCC progression in a CDK2-independent manner in mice and man. Therefore, interventional inactivation of CCNE1 represents a promising strategy the treatment of liver cancer.

INPP5F Translocates Into Cytoplasm And Interacts With ASPH To Promote Tumor Growth in Hepatocellular Carcinoma

Background: Increasing evidence has suggested inositol polyphosphate 5-phosphatase family contributes to tumorigenesis and tumor progression. However, the role of INPP5F in hepatocellular carcinoma (HCC) and its underlying mechanisms is unclear.Methods: The expression of INPP5F in HCC was analyzed in public databases and our clinical specimens. The biological functions of INPP5F were investigated in vitro and vivo. The molecular mechanism of INPP5F in regulating tumor growth were studied by transcriptome-sequencing analysis, mass spectrometry analysis, immunoprecipitation assay and immunofluorescence assay.Results: High expression of INPP5F was found in HCC tissues and was associated with poor prognosis in HCC patients. Overexpression of INPP5F promoted HCC cell proliferation, and vice versa. Knockdown of INPP5F suppressed tumor growth in vivo. Results from transcriptome-sequencing analysis showed INPP5F not only regulated a series of cell cycle related genes expression (c-MYC and cyclin E1), but also promoted many aerobic glycolysis related genes expression. Further studies confirmed that INPP5F could enhance lactate production and glucose consumption in HCC cell. Mechanistically, INPP5F activated Notch signaling pathway and upregulated c-MYC and cyclin E1 in HCC via interacting with ASPH. Interestingly, INPP5F was commonly nuclear-located in cells of adjacent non-tumor tissues, while in HCC, cytoplasm-located was more common. LMB (nuclear export inhibitor) treatment restricted INPP5F in nucleus and was associated with inhibition of Notch signaling and cell proliferation. Sequence of nuclear localization signals (NLSs) and nuclear export signals (NESs) in INPP5F aminoacidic sequence were then identified. Alteration of the NLSs or NESs influenced the localization of INPP5F and the expression of its downstream molecules. Furthermore, we found INPP5F interacted with both exportin and importin through NESs and NLSs, respectively, but the interaction with exportin was stronger, leading to cytoplasmic localization of INPP5F in HCC. Conclusion: These findings indicate that INPP5F functions as an oncogene in HCC via a translocation mechanism and activating ASPH-mediated Notch signaling pathway. INPP5F may serve as a potential therapeutic target for HCC patients.