Estrogen induces LCAT to maintain cholesterol homeostasis and suppress hepatocellular carcinoma development.

Hepatocellular carcinoma (HCC) is an aggressive disease that occurs predominantly in men. Estrogen elicits protective effects against HCC development. Elucidation of the estrogen-regulated biological processes that suppress HCC could lead to improved prevention and treatment strategies. Here, we performed transcriptomic analyses on mouse and human liver cancer and identified LCAT as the most highly estrogen-upregulated gene and a biomarker of favorable prognosis. LCAT upregulation inhibited HCC in vitro and in vivo and mediated estrogen-induced suppression of HCC in an ESR1-dependent manner. LCAT facilitated high-density lipoprotein cholesterol (HDL-C) production and uptake via the LDLR and SCARB1 pathways. Consistently, high HDL-C levels corresponded to a favorable prognosis in HCC patients. The enhanced HDL-C absorption induced by LCAT impaired SREBP2 maturation, which ultimately suppressed cholesterol biosynthesis and dampened HCC cell proliferation. HDL-C alone inhibited HCC growth comparably to the cholesterol-lowering drug lovastatin, and SREBF2 overexpression abolished the inhibitory activity of LCAT. Clinical observations and cross-analyses of multiple databases confirmed the correlation of elevated LCAT and HDL-C levels to reduced cholesterol synthesis and improved HCC patient prognosis. Furthermore, LCAT deficiency mimicked whereas LCAT overexpression abrogated the tumor growth promoting effects of ovariectomy in HCC-bearing female mice. Most importantly, HDL-C and LCAT delayed the development of subcutaneous tumors in nude mice, and HDL-C synergized with lenvatinib to eradicate orthotopic liver tumors. Collectively, this study reveals that estrogen upregulates LCAT to maintain cholesterol homeostasis and dampen hepatocarcinogenesis. LCAT and HDL-C represent potential prognostic and therapeutic biomarkers for targeting cholesterol homeostasis as a strategy for treating HCC.

Efficacy and safety analysis of hypofractionated and conventional fractionated radiotherapy in postoperative breast cancer patients.

OBJECTIVES: In this meta-analysis, we conducted a comparative analysis of the safety and efficacy of hypofractionated and conventional fractionated radiotherapy in individuals who had undergone surgery for breast cancer. METHODS: This study involved a systematic and independent review of relevant research articles published in reputable databases such as PubMed, Embase, Cochrane Library, and Web of Science. Two investigators conducted the review, which included studies published up to January 3, 2023. The quality of the eligible studies was evaluated and data were extracted using Review Manager software 5.4 (RevMan 5.4) to calculate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: The analysis comprised 35 studies and encompassed a collective sample of 18,246 individuals diagnosed with breast cancer. We did not find a statistically significant disparity in efficacy between conventional fractionated (CF) radiotherapy and hypofractionated (HF) radiotherapy regarding local recurrence (LR; OR = 0.91, 95% CI: 0.76-1.09, P = 0.30), disease-free survival (DFS; OR = 1.20, 95% CI: 1.01-1.42, P = 0.03), and overall survival (OS; OR = 1.08, 95% CI: 0.93-1.26, P = 0.28). Concerning safety, there was no significant difference between the HF and CF regimens in terms of breast pain, breast atrophy, lymphedema, pneumonia, pulmonary fibrosis, telangiectasia, and cardiotoxicity. However, the HF regimen resulted in lower skin toxicity (OR = 0.43, 95% CI: 0.33-0.55, P < 0.01) and improved patient fatigue outcomes (OR = 0.73, 95% CI: 0.60 - 0.88, P < 0.01). CONCLUSIONS: Although there is no substantial difference in LR, DFS, OS, or many other side effects between the HF and CF regimens, the HF regimen reduces skin toxicity and relieves patient fatigue. If these two issues need to be addressed in clinical situations, the HF regimen may be a superior alternative to conventional radiotherapy in postoperative breast cancer patients.

OTUB1 accelerates hepatocellular carcinoma by stabilizing RACK1 via its non-canonical ubiquitination.

BACKGROUND: Dysregulated ubiquitination modification occupies a pivotal role in hepatocellular carcinoma (HCC) tumorigenesis and progression. The ubiquitin aldehyde binding 1 (OTUB1) was aberrantly upregulated and exhibited the pro-tumorigenic function in HCC. However, the underlying mechanisms and responsible targets of OTUB1 remain unclear. METHODS: First, bioinformatics analysis, western blot and immunohistochemistry staining were applied to analyze OTUB1 expression in HCC specimens. Then, immunoprecipitation assay-tandem mass spectrometry (MS) combined with the gene set enrichment analysis (GSEA) was used to explore the downstream target of OTUB1. Co-immunoprecipitation and ubiquitination assays were used to identify the mechanisms involved. Finally, we explored the regulatory effect of MAZ on OTUB1 through ChIP-qPCR and dual-luciferase reporter assay. RESULTS: OTUB1 was broadly elevated in HCC tissues and promoted the proliferation and metastasis of HCC in vitro and in vivo. The receptor for activated C kinase 1 (RACK1) performed as a functional partner of OTUB1 and its hyperactivation was associated with aggressive development and other malignant features in HCC by activating oncogenes transcription. Mechanistically, OTUB1 directly bound to RACK1 at its C-terminal domain and decreased the K48-linked ubiquitination of RACK1 through its non-canonical suppression of ubiquitination activity, which stabilized RACK1 protein levels in HCC cells. Therefore, OTUB1 significantly increased multiple oncogenes expression and activated PI3K/AKT and FAK/ERK signaling in a RACK1-dependent manner in HCC. Moreover, the transcription factor MAZ upregulated OTUB1 expression through identifying a putative response element of OTUB1 promoter area. CONCLUSIONS: Our findings might provide a new therapeutic strategy for HCC by modifying the MAZ-OTUB1-RACK1 axis.

Site-specific controlled-release nanoparticles for immune reprogramming via dual metabolic inhibition against triple-negative breast cancer.

Metabolic heterogeneity and the tumor immunosuppressive microenvironment (TIME) of triple-negative breast cancer (TNBC) hinder therapeutic effectiveness. Although emerging metabolic therapy and immunotherapy show promise, they are limited by off-target effects and immune escape. Here, a redox-activatable, sequentially-releasing nanoparticle (AMANC@M) for tumor-targeted delivery of anticancer agents and CRISPR/Cas9 has been developed. AMANC@M can reverse the TIME through dual metabolic inhibition, thereby enhancing TNBC therapy. AMANC@M demonstrates excellent biosafety and targets tumors precisely through biomimetic hybrid membrane-mediated homologous homing and the enhanced permeability and retention (EPR) effect. Once internalized into tumor cells, the CRISPR/Cas9 system ("energy nanolock") is released through glutathione (GSH) cleavage and effectively knocks down the expression of lactate dehydrogenase A (LDHA) to suppress glycolysis. After peeling off of the gene editing shell, a newly synthesized targeted drug, CPI-Z2 ("nutrihijacker" and "energy nanolock"), is released in a controlled manner to block the mitochondrial tricarboxylic acid (TCA) cycle. Nitric oxide (NO) produced from loaded L-arginine enhances the efficiency of CPI-Z2 and reduces drug resistance. Combined with NO therapy, both blockades of nutrients and energy production transform the hypoxia and acidic TIME into an immunocompetent tumor microenvironment (TME) for tumor elimination. Furthermore, AMANC@M offers capabilities for photothermal (PT) therapy and provides clear imaging through PT, photoacoustic (PA), or computed tomography (CT) signals in tumor tissue. Thus, this study provides a new and promising sequentially stimuli-responsive targeting strategy for nanoparticle development, making it a potential treatment candidate for TNBC and other tumors.

Long noncoding RNA X-inactive specific transcript (lncRNA XIST) inhibits hepatic insulin resistance by competitively binding microRNA-182-5p.

BACKGROUND: What is highlighted in this study refers to the role and molecular mechanism of long noncoding RNA (lncRNA) X-inactive specific transcript (XIST) in cells with insulin resistance (IR). METHODS: In this study, LX-2 cells were applied to establish IR model in vitro. The expressions of lncRNA XIST, phosphoenolpyruvate carboxykinase (PEPCK,) and glucose-6-phosphatase (G6Pase) were quantified by quantitative reverse transcription polymerase chain reaction. The 2-deoxy-d-glucose-6-phosphate (2-DG6P) level was detected utilizing 2-deoxy-d-glucose (2-DG) uptake measurement kit. Western blot was adopted to measure the protein expressions of insulin-like growth factor-1 receptor (IGF-1R), G6Pase, PEPCK, and phosphatidylinositol 3-kinase (PI3K)/Akt pathway-related genes. StarBase was used to predict the targeting relationship between lncRNA XIST or IGF-1R with miR-182-5p, the results of which were verified by dual-luciferase reporter, RNA pull-down, and RNA immunoprecipitation assays. Rescue experiments were conducted to investigate the effect of miR-182-5p on IR cells. Next, low-expressed lncRNA XIST and high-expressed miR-182-5p were observed in IR cells. RESULTS: Upregulation of lncRNA XIST increased IGF-1R and 2-DG6P levels, decreased G6Pase and PEPCK expressions, and promoted PI3K/Akt pathway activation in IR cells. LncRNA XIST sponged miR-182-5p which targeted IGF-1R. MiR-182-5p mimic reversed the above effects of lncRNA XIST overexpression on IR cells. CONCLUSIONS: In conclusion, lncRNA XIST/miR-182-5p axis alleviates hepatic IR in vitro via IGF-1R/PI3K/Akt signaling pathway, which could be the promising therapeutic target.

OBIA: An Open Biomedical Imaging Archive.

With the development of artificial intelligence (AI) technologies, biomedical imaging data play an important role in scientific research and clinical application, but the available resources are limited. Here we present Open Biomedical Imaging Archive (OBIA), a repository for archiving biomedical imaging and related clinical data. OBIA adopts five data objects (Collection, Individual, Study, Series, and Image) for data organization, and accepts the submission of biomedical images of multiple modalities, organs, and diseases. In order to protect personal privacy, OBIA has formulated a unified de-identification and quality control process. In addition, OBIA provides friendly and intuitive web interfaces for data submission, browsing, and retrieval, as well as image retrieval. As of September 2023, OBIA has housed data for a total of 937 individuals, 4136 studies, 24,701 series, and 1,938,309 images covering 9 modalities and 30 anatomical sites. Collectively, OBIA provides a reliable platform for biomedical imaging data management and offers free open access to all publicly available data to support research activities throughout the world. OBIA can be accessed at https://ngdc.cncb.ac.cn/obia.

Cardiorespiratory dose comparison among six radiotherapy regimens for patients with left-sided breast cancer.

There is uncertainty regarding the benefits and drawbacks of various radiation protocols for the treatment of left-sided breast cancer. To address this issue, we conducted a Bayesian network analysis. First, we searched several electronic databases for eligible literature. Next, we pooled the data from twelve studies concerning three-dimensional conformal radiation therapy (3D-CRT), intensity modulated radiation therapy (IMRT), and volumetric modulated arc therapy (VMAT), combined with either deep inspiratory breath-holding (DIBH) or free-breathing (FB) modalities. The integrated cardiac and pulmonary dosimetric indexes for all included treatments were compared using Bayesian networks. A direct meta-analysis indicated that for the two methods of 3D-CRT and IMRT, DIBH technology was more effective than FB in reducing the radiation dose to the heart and lungs. Additionally, according to the network results, DIBH was superior to FB in all six treatment options, regardless of whether the plan was 3D-CRT, IMRT, or VMAT. Besides, the combined data indicated that the FB-3D-CRT regimen had the weakest dosimetric advantage of all the treatments. Excluding FB-3D-CRT, each of the other five treatments had its own specific benefits. This is the first Bayesian study of several radiotherapy regimens for breast cancer patients on the left side, and the findings can be used to select appropriate radiotherapy programs for breast cancer patients.

Promoting the formation of Pi-stacking interaction to improve CTL cells activation between modified peptide and HLA.

OBJECTIVE: This study aims to investigate the use of single residue substitution to promote the formation of pi-stacking interactions between peptides and Human leukocyte antigen (HLA)-A*2402 molecules to improve the affinity of peptides and HLA molecules, as well as the level of cytotoxic T lymphocyte (CTL) cells activated by peptides-HLA (p-HLA) complex. METHODS: Molecular docking and molecular dynamics simulation were used to simulate and analyze the interactions and binding free energies between HLA-A*2402-restricted antigen peptides and HLA molecules, before and after the single residue substitution. HLA-A*2402 restricted antigen peptides before and after the single residue replacement were loaded into dendritic cells (DCs) in vitro, and further Enzyme-Linked ImmunoSpot (ELispot) test was carried out to evaluate the effect of modified antigen peptides on the immune activation of CTL cells. RESULT: After replacing the antigen peptides with a single residue, some of them could promote the formation of pi-stacking interaction. The binding free energy between the modified antigen peptides and HLA-A*2402, as well as the level of immune activation of CTL cells were mostly higher than before, especially after the replacement of the 9th residue of the polypeptide, such as C9F and C9W. There was a significant negative correlation between the level of activated CTL cells by modified antigen peptides and the total interaction amount of hydrogen bonds and salt bridges. CONCLUSION: Promoting the formation of pi-stacking interaction between antigen peptides and HLA-A*2402 molecules could increase the total binding free energy of p-HLA complex and the level of CTL cells activation. In addition, the amount of hydrogen bonds and salt bridges between peptides and HLA could reduce the level of immune activation. All the characteristics above can improve the immunogenicities of the weak antigens.

Coexistence of submandibular epithelioid angiosarcoma and papillary thyroid carcinoma: A case report.

INTRODUCTION: Reports on the coexistence of epithelioid angiosarcoma (EA) and papillary thyroid carcinoma (PTC) are rare. Over the past 50 years, only 2 cases of coexistence of EA and PTC have been reported in English literature. Therefore, we report a rare case of coexistence of EA and PTC treated with surgery and adjuvant radiation therapy. PATIENT CONCERNS: A 64-year-old man visited our hospital with a painless mass in the left submandibular gland, with poor mobility. DIAGNOSIS: Neck ultrasonography revealed nodules in the left submandibular gland and multiple cystic-solid mixed nodules in the left thyroid gland. Pathological findings revealed coexistence of EA in the left submandibular gland area and PTC in the left thyroid gland. INTERVENTIONS: The patient underwent resection of the left submandibular gland, deep maxillofacial tumor, total thyroidectomy, left neck I, II, III, and VI regional lymph node dissection, and recurrent laryngeal nerve exploration under general anesthesia. Two months postoperatively, the patient also received adjuvant radiation therapy in the local and adjacent areas, with 4MV-X IMRT DT50GY at 2Gy/day 25 fractions. OUTCOMES: The follow-up period was 37 months. The patient recovered well without focal neurological deficits, local recurrence, or distant metastasis after surgery, except for grade I skin reaction after adjuvant radiation therapy. CONCLUSIONS: This is a rare case report of the coexistence of EA in the left submandibular gland and PTC in the left thyroid gland. Although multiple examinations were used, precise preoperative diagnosis was challenging owing to the coexistence of EA and PTC. Surgery and radiotherapy were effective treatments for the coexistence of EA and PTC in this case.

Diagnosis and Prediction of Endometrial Carcinoma Using Machine Learning and Artificial Neural Networks Based on Public Databases.

Endometrial carcinoma (EC), a common female reproductive system malignant tumor, affects thousands of people with high morbidity and mortality worldwide. This study was aimed at developing a prediction model for the diagnosis of EC in the general population. First, we obtained datasets GSE63678, GSE106191, and GSE115810 from the Gene Expression Omnibus (GEO) database, dataset GSE17025 from the GEO database, and the RNA sequence of EC from The Cancer Genome Atlas (TCGA) database to constitute the training, test, and validation groups, respectively. Subsequently, the 96 most significantly differentially expressed genes (DEGs) were identified and analyzed for function and pathway enrichment in the training group. Next, we acquired the disease-specific genes by random forest and established an artificial neural network for the diagnosis. Receiver operating characteristic (ROC) curves were utilized to identify the signature across the three groups. Finally, immune infiltration was analyzed to reveal tumor-immune microenvironment (TIME) alterations in EC. The top 96 DEGs (77 down-regulated and 19 up-regulated genes) were primarily enriched in the interleukin-17 signaling pathway, protein digestion and absorption, and transcriptional misregulation in cancer. Subsequently, 14 characterizing genes of EC were identified by random forest. In the training, test, and validation groups, the artificial neural network was constructed with high diagnostic accuracies of 0.882, 0.864, and 0.839, respectively, and areas under the ROC curve (AUCs) of 0.928, 0.921, and 0.782, respectively. Finally, resting and activated mast cells were found to have increased in TIME. We constructed an artificial diagnostic model with excellent reliability for EC and uncovered variations in the immunological ecosystem of EC through integrated bioinformatics approaches, which might be potential diagnostic targets for EC.

Circular RNA ITCH attenuates the progression of nasopharyngeal carcinoma by inducing PTEN upregulation via miR-214.

BACKGROUND: Circular RNA itchy E3 ubiquitin protein ligase (circ-ITCH) has previously been reported to play a key role in carcinogenesis. Nevertheless, the role of circ-ITCH in nasopharyngeal carcinoma (NPC) remains to be explored. METHODS: Gene expression analysis was performed using a quantitative real-time polymerase chain reaction, western blotting and immunohistochemistry. The role of circ-ITCH in NPC was explored using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide, colony formation, transwell invasion, scratch healing and xenograft tumor assays. Furthermore, luciferase reporter assay was carried out to assess the interactions among circ-ITCH, microRNA-214 (miR-214) and phosphatase and tensin homolog (PTEN). RESULTS: The levels of circ-ITCH and PTEN were decreased, whereas the level of miR-214 was increased in NPC tissues collected from 28 subjects compared to normal nasopharynx tissues collected from 15 subjects. Moreover, a negative correlation between circ-ITCH and miR-214 expression and a positive correlation between circ-ITCH and PTEN expression were observed in NPC tissues. Downregulation of circ-ITCH expression was also observed in NPC cell lines. In addition, upregulation of circ-ITCH markedly inhibited NPC cell proliferation, migration and invasion. Furthermore, circ-ITCH was confirmed to exert its function by sponging miR-214. PTEN was found to be a direct target gene of miR-214 and its expression was negatively correlated with miR-214 expression in NPC tissues. Moreover, our results showed that the circ-ITCH/miR-214 axis regulated NPC proliferation, migration and invasion through regulating the expression of PTEN. Upregulation of circ-ITCH or PTEN blocked miR-214-mediated promotion of NPC tumorigenesis in vitro. Additionally, upregulation of circ-ITCH also suppressed NPC tumorigenesis in vivo. CONCLUSIONS: The present study demonstrated that circ-ITCH suppressed NPC tumorigenesis by upregulating PTEN expression through interacting with miR-214, thus proposing a novel mechanism for NPC inhibition.

The Role, Function, and Mechanism of Long Intergenic Noncoding RNA1184 (linc01184) in Colorectal Cancer.

BACKGROUND: Long intergenic noncoding RNA1184 (linc01184) has been recently discovered; however, its role in human diseases is limited to date. The present study is aimed at investigating the expression pattern and mechanism of linc01184 in colorectal cancer (CRC) tumorigenesis. METHODS: The expression of linc01184 in CRC tissues and cell lines was compared with that in normal controls. The functions of linc01184 in CRC cells were identified by overexpression and small interfering RNA (siRNA) approaches in vitro. Meanwhile, the target gene prediction software, luciferase reporter, RNA pull-down, and western blotting assays were used to analyze the oncogenic mechanism. RESULTS: We found that linc01184 was obviously upregulated in CRC tissues and cells when compared to normal controls, and its upregulation had a positive association with the CRC progression. linc01184 knockdown significantly suppressed CRC cell proliferation and invasion and promoted apoptosis. Besides, linc01184 acted as a competitive endogenous RNA (ceRNA) by directly binding to microRNA-331 (miR-331), and its overexpression resulted in notable increases of human epidermal growth factor receptor 2 (HER2), phosphorylated Ser/Thr kinases (p-Akt), and extracellular regulated protein kinase 1/2 (p-ERK1/2) at posttranscriptional levels in CRC cells, which were antagonized by miR-331. CONCLUSIONS: The findings reveal for the first time that linc01184 is an enhancer for the proliferation and invasion of CRC by functioning as a ceRNA through the linc01184-miR-331-HER2-p-Akt/ERK1/2 pathway regulatory network.

Identifying prognostic biomarkers in endometrial carcinoma based on ceRNA network.

PURPOSE: Endometrial carcinoma (EC), a common gynecological malignancy with high incidence, affects the mental and physical health of women. Mounting evidence shows that long noncoding RNAs (lncRNAs), messenger RNAs (mRNAs), and microRNAs (miRNAs) have instrumental roles in various biological processes associated with the pathogenesis of EC. In this research, we intend to further study the mechanism of EC and the potential predictive markers of EC. METHODS: First, we obtained original data of EC RNA transcripts from The Cancer Genome Atlas database and performed differential analysis. Subsequently, according to the miRcode online software, relationship pairs of lncRNA-miRNA were constructed, and miRNA-mRNA pairs were established based on miRDB, TargetScan, and miRTarBase. Then, we constructed the competing endogenous RNA (ceRNA) network based on lncRNA-miRNA and miRNA-mRNA pairs. To further explain the function of the ceRNA network and explore the potential prognostic markers, functional enrichment analysis, and survival analysis were carried out. RESULTS: The research showed that there were 744 differential expression lncRNAs (DElncRNAs), 164 differential expression miRNAs (DEmiRNAs), and 2447 differential expression mRNAs (DEmRNAs) between EC tissues and normal tissues. Subsequently, we built 103 DEmiRNA-DEmRNA interaction pairs and 369 DElncRNA-DEmiRNA pairs. Then, we established the ceRNA network of EC, including 62 DElncRNAs, 26 DEmiRNAs, and 70 DEmRNAs. Moreover, 10 of 62 lncRNAs, 19 of 70 mRNAs, and 4 of 26 miRNAs that closely related to the survival of EC with P < .05 were obtained. Notably, based on this network, it was found that LINC00261-hsa-mir-31 pair and LINC00261-hsa-mir-211 target pairs could be used as the potential prognostic markers of EC. CONCLUSION: This research recommended an available basis for the molecular mechanism of EC and prognosis prediction, which could help guide the subsequent treatments and predict the prognosis for patients with EC.

A temperature-sensitive phase-change hydrogel of tamoxifen achieves the long-acting antitumor activation on breast cancer cells.

Background: Breast cancer is one of the foremost threats to female health nowadays. Tamoxifen, an antagonist of estrogen receptor-α (ERα), is the first choice for endocrine-dependent breast cancer (ERα-positive breast cancer) treatment. However, ERα has an important function in the normal physical regulation of estrogen, and current oral administration of tamoxifen has potential side effects on normal endocrine secretion. In the present work, we aim to develop novel approaches to increase the antitumor effect of tamoxifen on breast cancer cells and decrease the potential side effects in the human body during treatment. Methods: A temperature-sensitive phase-change hydrogel for tamoxifen (Tam-Gel) was generated. After establishing subcutaneous tumors formed by MCF-7, an ERα-positive breast cancer cell line, in nude mice, an intratumoral injection of Tam-Gel was performed to examine whether Tam-Gel facilitated the slow-release or antitumor effect of tamoxifen. A metastatic breast cancer model was established using the intrahepatic growth of MCF-7 cells in immunodeficient rats. Results: Tam-Gel can transform from liquid to hydrogel at room temperature. An intratumoral injection of Tam-Gel facilitated the slow-release or antitumor effect of tamoxifen. Once Tam-Gel, but not Tam-Sol, was administered by intratumoral injection, it significantly decreased the uptake of radionuclide probes (18F-fluoroestradiol or 18F-fluorodeoxyglucose) by cells in rats' livers and the intrahepatic growth of MCF-7 cells in rats' livers. Conclusion: A novel slow-release system was successfully prepared to facilitate the long-term release of tamoxifen in breast cancer tissues, and achieved an antitumor effect in the long term.

MicroRNA-645 targets urokinase plasminogen activator and decreases the invasive growth of MDA-MB-231 triple-negative breast cancer cells.

BACKGROUND: Urokinase plasminogen activator (uPA) promotes the in vivo invasive growth of HCC cells by cleaving and activating matrix metalloproteinases (MMPs) to induce the destruction of the extracellular matrix of triple-negative breast cancer (TNBC) cells. The identification of microRNAs that target uPA and decrease uPA expression would be useful for attenuating the in vivo invasive growth of TNBC cells. MATERIALS AND METHODS: MicroRNA-645 (miR-645) was identified using an online tool (miRDB) as potentially targeting uPA; miR-645 inhibition of uPA was confirmed by western blot experiments. The effects of miR-645 on the in vivo invasive growth of TNBC cells were examined using an intrahepatic tumor model in nude mice, and the miR-645 mechanism of action was explored with MMP cleaving experiments. RESULTS: Through virtual screening, we discovered that miR-645 potentially targeted the uPA 3' untranslated region. This targeting was confirmed by western blot experiments and miR-645 lentiviral particle (LV-645) transduction that inhibited uPA expression in MDA-MB-231 TNBC cells. The LV-645 inhibition of uPA led to the decreased invasive growth of TNBC cells in nude mice. The mechanism data indicated that the uPA inhibition resulted in a decreased cleaving of the pro-MMP-9 protein. CONCLUSION: Targeting uPA with miR-645 decreased the in vivo invasive growth of TNBC cells. These results suggest that miR-645 may represent a promising treatment strategy for TNBC.

A20 enhances the radiosensitivity of hepatocellular carcinoma cells to 60Co-γ ionizing radiation.

The radioresistance of hepatocellular carcinoma (HCC) cells is a critical obstacle for effectively applying radiotherapy (RT) in HCC treatment. NF-κB, an important transcription factor, can influence critical cell fate decisions by promoting cell survival or anti-apoptosis in response to cell-stress, e.g. chemotherapies or ionizing radiation (IR). A20, also named as tumor necrosis factor α induced protein 3 (TNFAIP3), is a dominant negative regulator of NF-κB pathway and its functions in HCC are largely unknown. The present work aimed to reveal the role of A20 plays in affecting the radiosensitivity of HCC cells. Higher expression of A20 was detected in hepatic non-tumor cell line or clinical specimens compared with HCC cell lines or clinical specimens. A20 decreased the expression of proteins mediating cellular stress/injury response or epithelial-mesenchymal transition (EMT) process. Overexpression of A20 via adenovirus enhanced the effect of 60Co-γ ionizing radiation (IR) on HCC cells' injury, e.g. G2/M arrest or DNA double strands break (DSB). Moreover, A20 also enhanced the in vitro or in vivo survival inhibiting of HCC cells induced by IR. These results reveal the roles of A20 in HCC radiosensitization and overexpression of A20 would be a novel strategy for HCC radiotherapy.

Human GPR4 and the Notch signaling pathway in endothelial cell tube formation.

G protein-coupled receptor 4 (GPR4) is hypothesized to function as a pH sensor and is important in the regulation of proliferation, migration and angiogenesis of vascular endothelial cells (ECs). Furthermore, the Notch signaling pathway is significant in the regulation of the angiogenic behavior of ECs. However, whether GPR4 regulates angiogenesis via the Notch signaling pathway remains unclear. The present study evaluated the effect of Notch signaling in human GPR4­induced angiogenesis in HMEC­1 cells. The results revealed that GPR4 increased Notch1 expression in a time­dependent manner. In addition, the inhibition of Notch1 expression using small interfering RNA or the Notch receptor inhibitor, γ-secretase inhibitor I, significantly blocked GPR4­induced HMEC­1 tube formation and lymphocyte transendothelial migration. Furthermore, the inhibition of Notch1 blocked GPR4­induced vascular endothelial growth factor and hypoxia-inducible factor 1α expression. Thus, it was demonstrated that GPR4 affects ECs by regulating Notch1, a function that may be important for physiological and pathological angiogenesis.

MiR-331-3p inhibits proliferation and promotes apoptosis by targeting HER2 through the PI3K/Akt and ERK1/2 pathways in colorectal cancer.

MicroRNAs (miRNAs) regulate cell proliferation, apoptosis and carcinogenesis by targeting related mRNAs in different types of cancer. miR-331-3p has been found to regulate the development and progression of various types of cancer cells. However, little research has been conducted on the role of miR-331-3p in colorectal cancer (CRC). The present study aimed to explore the function of miR-331-3p in CRC. We found that miR-331-3p was significantly downregulated in CRC tissues and cells compared to the level in healthy colon tissues and cells. Overexpression of miR-331-3p by transfection with pre­miR-331-3p inhibited cell proliferation, promoted apoptosis and activated caspase-3. Furthermore, the protein expression level of apoptosis-related protein Bcl-2 was downregulated and Bax was upregulated by pre­miR­331-3p. Downregulation of the expression of miR-331-3p by transfection with AS-miR-331-3p had the opposite effect. Moreover, we found that HER2 was overexpressed in the CRC cell lines, and the expression level of HER2 was negatively regulated by miR­331-3p. Additionally, knockdown of HER2 inhibited cell proliferation and phosphorylation of Akt and ERK1/2 induced by AS-miR-331-3p. Overall, we identified that miR­331-3p is underexpressed in CRC and contributes to cell growth regulation by targeting HER2 through activating the PI3K/Akt and ERK1/2 signaling pathways.