Ovarian cancer is the most lethal gynecologic malignancy, but its etiology remains poorly understood. This study investigated the role of Fli-1 in ovarian carcinogenesis and disease survival.

Gene single nucleotide polymorphisms (SNPs) have been extensively studied in association with development and prognosis of various malignancies. However, the potential role of genetic polymorphisms of cancer stem cell (CSC) marker genes with respect to cancer risk has not been examined. We conducted a case-control study involving a total of 1000 subjects (500 lung cancer patients and 500 age-matched cancer-free controls) from northeastern China. Lung cancer risk was analyzed in a logistic regression model in association with genotypes of four lung CSC marker genes (CD133, ALDH1, Musashi-1, and EpCAM). Using univariate analysis, the Musashi-1 rs2522137 GG genotype was found to be associated with a higher incidence of lung cancer compared with the TT genotype. No significant associations were observed for gene variants of CD133, ALDH1, or EpCAM. In multivariate analysis, Musashi-1 rs2522137 was still significantly associated with lung cancer when environmental and lifestyle factors were incorporated in the model, including lower BMI; family history of cancer; prior diagnosis of chronic obstructive pulmonary disease, pneumonia, or pulmonary tuberculosis; occupational exposure to pesticide; occupational exposure to gasoline or diesel fuel; heavier smoking; and exposure to heavy cooking emissions. The value of the area under the receiver-operating characteristic (ROC) curve (AUC) was 0.7686. To our knowledge, this is the first report to show an association between a Musashi-1 genotype and lung cancer risk. Further, the prediction model in this study may be useful in determining individuals with high risk of lung cancer.

Recent studies have focused on the significant cytotoxicity of natural killer (NK) cells, cytokine-induced killer (CIK) cells, and gamma-delta (γδ) T cells in tumor cells. Nevertheless, the therapeutic features of these cell types have not been compared in the literature. The aim of this study was to evaluate the feasibility of activation and expansion of NK, CIK, and γδ T cells from cancer patients in vitro, and to clarify the differences in their antitumor capacities.

Hormesis and adaptive responses are 2 important biological effects of low-dose ionizing radiation (LDR). In normal tissue, LDR induces hormesis as evinced by increased cell proliferation; however, whether LDR also increases tumor cell proliferation needs to be investigated. In this study, cell proliferation was assayed by total cell numbers and the Cell Counting Kit 8 assay. Mitogen-activated protein kinases (MAPK)/extracellular signal-regulated kinase (ERK) and phosphatidylinositol 3' -kinase(PI3K)-Akt (PI3K/AKT) phosphorylation were determined by Western blot analysis. Human embryonic lung fibroblast 2BS and lung cancer NCI-H446 cell lines were irradiated with LDR at different doses (20-100 mGy). In response to 20 to 75 mGy X-rays, cell proliferation was significantly increased in 2BS but not in NCI-H446 cells. In 2BS cells, LDR at 20 to 75 mGy also stimulated phosphorylation of MAPK/ERK pathway proteins including ERK, MEK, and Raf and of the PI3K/AKT pathway protein AKT. To test whether ERK1/2 and AKT pathway activation was involved in the stimulation of cell proliferation in 2BS cells, the MAPK/ERK and PI3K/AKT pathways were inhibited using their specific inhibitors, U0126 and LY294002. U0126 decreased the phosphorylation of ERK1/2, and LY294002 decreased the phosphorylation of AKT; each could significantly inhibit LDR-induced 2BS cell proliferation. However, LDR did not stimulate these kinases, and kinase inhibitors also did not affect cell proliferation in the NCI-H446 cells. These results suggest that LDR stimulates cell proliferation via the activation of both MAPK/ERK and PI3K/AKT signaling pathways in 2BS but not in NCI-H446 cells. This finding implies the potential for applying LDR to protect normal tissues from radiotherapy without diminishing the efficacy of tumor therapy.

The bacterial defense system CRISPR (clustered regularly interspaced short palindromic repeats) has been explored as a powerful tool to edit genomic elements. In this study, we test the potential of CRISPR Csy4 RNA endoribonuclease for targeting HIV-1. We fused human codon-optimized Csy4 endoribonuclease with VPR, a HIV-1 viral preintegration complex protein. An HIV-1 cell model was modified to allow quantitative detection of active virus production. We found that the trans-expressing VPR-Csy4 almost completely blocked viral infection in two target cell lines (SupT1, Ghost). In the MAGI cell assay, where the HIV-1 LTR β-galactosidase is expressed under the control of the tat gene from an integrated provirus, VPR-Csy4 significantly blocked the activity of the provirus-activated HIV-1 reporter. This proof-of-concept study demonstrates that Csy4 endoribonuclease is a promising tool that could be tailored further to target HIV-1.

The insulin-like growth factor II (IGF2) gene is aberrantly expressed in tumors as a result of loss of imprinting (LOI). Reactivation of the normally-suppressed maternal allele may lead to IGF2 upregulation and increased tumor growth, particularly in colon cancer. However, the mechanisms underlying IGF2 LOI in tumors are poorly defined. In this report, we identified polycomb repressive complex 2 (PRC2) docking factor SUZ12 as a critical factor in regulating IGF2 imprinting in tumors. Human colon cancer cell lines (HRT18 and HT29) show loss of IGF2 imprinting. Ectopic expression of SUZ12 restored normal monoallelic expression of IGF2 in these two colon cancer cell lines. Using chromatin immunoprecipitation (ChIP) and chromatin conformation capture (3C), we found that the virally-expressed SUZ12 bound to IGF2 promoters, coordinating with endogenous CTCF to orchestrate a long range intrachromosomal loop between the imprinting control region (ICR) and the IGF2 promoters. The histone methyltransferase EZH2 was recruited to the IGF2 promoters, where it induced H3K27 hypermethylation, suppressing one allele, leading to the restoration of IGF2 imprinting. These data demonstrate that SUZ12 is a key molecule in the regulation of monoallelic expression of IGF2, suggesting a novel epigenetic therapeutic strategy for modulating IGF2 production in human tumors.

We studied the protective effect of stromal cell-derived factor-1β (SDF-1β) on cardiac cells from lipotoxicity in vitro and diabetes in vivo. Exposure of cardiac cells to palmitate increased apoptosis by activating NADPH oxidase (NOX)-associated nitrosative stress and endoplasmic reticulum (ER) stress, which was abolished by pretreatment with SDF-1β via upregulation of AMP-activated protein kinase (AMPK)-mediated p38 mitogen-activated protein kinase (MAPK) phosphorylation and interleukin-6 (IL-6) production. The SDF-1β cardiac protection could be abolished by inhibition of AMPK, p38 MAPK, or IL-6. Activation of AMPK or addition of recombinant IL-6 recaptured a similar cardiac protection. SDF-1β receptor C-X-C chemokine receptor type 4 (CXCR4) antagonist AMD3100 or CXCR4 small interfering RNA could not, but CXCR7 small interfering RNA completely abolished SDF-1β's protection from palmitate-induced apoptosis and activation of AMPK and p38 MAPK. Administration of SDF-1β to diabetic rats, induced by feeding a high-fat diet, followed by a small dose of streptozotocin, could significantly reduce cardiac apoptosis and increase AMPK phosphorylation along with prevention of diabetes-induced cardiac oxidative damage, inflammation, hypertrophy, and remodeling. These results showed that SDF-1β protects against palmitate-induced cardiac apoptosis, which is mediated by NOX-activated nitrosative damage and ER stress, via CXCR7, to activate AMPK/p38 MAPK-mediated IL-6 generation. The cardiac protection by SDF-1β from diabetes-induced oxidative damage, cell death, and remodeling was also associated with AMPK activation.

Hepatocellular carcinoma (HCC) is the second leading cause of cancer death in Asia; however, the molecular mechanism in its tumorigenesis remains unclear. Abnormal expression of claudins (CLDNs), a family of tight junction (TJ) proteins, plays an important role in the metastatic phenotype of epithelial-derived tumors by affecting tight junction structure, function and related cellular signaling pathways. In a previous study, we used a tissue chip assay to identify CLDN17 as an upregulated gene in HCC. Here we aimed to use molecular biology technology to explore the effect of CLDN17 on the malignant phenotype of HCC and the underlying molecular mechanism, with the objective of identifying a new target for HCC treatment and the control of HCC metastasis.

Small cell lung cancer (SCLC) is regarded as the most devastative type of human lung malignancies. The rapid and disseminated growth pattern remains the primary cause of poor clinical prognosis in patients with SCLC. However, the molecular factors that drive rapid progression of SCLC remain unclear. Friend leukemia virus integration 1 (FLI1), an Ets transcription factor family member, has been previously reported to act as a major driver of hematological malignancies. In this study, we explored the potential role of FLI1 in SCLC. Using immunohistochemical staining, we found that FLI1 was significantly upregulated in SCLC tissues, compared to that in non-small cell lung cancer (NSCLC) and normal lung tissues (p < 0.01). The expression score of FLI1 oncoprotein was associated with the extensive stage of SCLC and the overexpressed Ki67. Knockdown of FLI1 with small interfering RNA (siRNA) or short hairpin RNA (shRNA) promoted apoptosis and induced repression of cell proliferation, tumor colony formation and in vivo tumorigenicity in highly aggressive SCLC cell lines. Importantly, we discovered that FLI1 promoted tumorigenesis by activating the miR-17-92 cluster family. This study uncovers FLI1 as an important driving factor that promotes tumor growth in SCLC through the miR-17-92 pathway. FLI1 may serve as an attractive target for therapeutic intervention of SCLC.

Background. Fetal heart can regenerate to restore its normal anatomy and function in response to injury, but this regenerative capacity is lost within the first week of postnatal life. Although the specific molecular mechanisms remain to be defined, it is presumed that aging of cardiac stem or progenitor cells may contribute to the loss of regenerative potential. Methods. To study this aging-related dysfunction, we cultured mesenchymal stem cells (MSCs) from human fetal heart tissues. Senescence was induced by exposing cells to chronic oxidative stress/low serum. Mitochondrial DNA methylation was examined during the period of senescence. Results. Senescent MSCs exhibited flattened and enlarged morphology and were positive for the senescence-associated beta-galactosidase (SA-β-Gal). By scanning the entire mitochondrial genome, we found that four CpG islands were hypomethylated in close association with senescence in MSCs. The mitochondrial COX1 gene, which encodes the main subunit of the cytochrome c oxidase complex and contains the differentially methylated CpG island 4, was upregulated in MSCs in parallel with the onset of senescence. Knockdown of DNA methyltransferases (DNMT1, DNMT3a, and DNMT3B) also upregulated COX1 expression and induced cellular senescence in MSCs. Conclusions. This study demonstrates that mitochondrial CpG hypomethylation may serve as a critical biomarker associated with cellular senescence induced by chronic oxidative stress.

Background: Long non-coding RNAs (lncRNAs) constitute an important component of the regulatory apparatus that controls stem cell pluripotency. However, the specific mechanisms utilized by these lncRNAs in the control of pluripotency are not fully characterized. Methods: We utilized a RNA reverse transcription-associated trap sequencing (RAT-seq) approach to profile the mouse genome-wide interaction targets for lncRNAs that are screened by RNA-seq. Results: We identified Peblr20 (Pou5F1 enhancer binding lncRNA 20) as a novel lncRNA that is associated with stem cell reprogramming. Peblr20 was differentially transcribed in fibroblasts compared to induced pluripotent stem cells (iPSCs). Notably, we found that Peblr20 utilized a trans mechanism to interact with the regulatory elements of multiple stemness genes. Using gain- and loss-of-function experiments, we showed that knockdown of Peblr20 caused iPSCs to exit from pluripotency, while overexpression of Peblr20 activated endogenous Pou5F1 expression. We further showed that Peblr20 promoted pluripotent reprogramming. Mechanistically, we demonstrated that Peblr20 activated endogenous Pou5F1 by binding to the Pou5F1 enhancer in trans, recruiting TET2 demethylase and activating the enhancer-transcribed RNAs. Conclusions: Our data reveal a novel epigenetic mechanism by which a lncRNA controls the fate of stem cells by trans-regulating the Pou5F1 enhancer RNA pathway. We demonstrate the potential for leveraging lncRNA biology to enhance the generation of stem cells for regenerative medicine.

Breast cancer is the most common cancer in women worldwide; despite the developments in diagnosis and therapy, recurrence and metastasis remain the main causes of death among patients with breast cancer. This study aimed to identify a promising biomarker for this disease. The study clarified (1) the association between Friend leukemia virus integration 1 (FLI-1) and various molecular subtypes and (2) the prognostic value of FLI-1 in breast cancer. To the best of our knowledge, this study is the first to report that FLI-1 is a predictor of poor prognosis in patients with breast cancer and overexpressed in the triple negative breast cancer (TNBC) subtype. To further verify the effect of FLI-1 in promoting the metastasis of TNBC, we performed a series of functional experiments in vitro and orthotopic xenograft experiments in the mammary fat pad of nude mice. FLI-1, as a transcription factor, bound to the promoters of key EMT-related genes (CDH1 and VIM), and regulated their expressions at the transcriptional level, thus induced epithelial-mesenchymal transition (EMT). The overexpression of FLI-1 significantly upregulated the expression of mesenchymal markers. After the modulation of FLI-1, the changes in mammary stem cell markers (ALDH1A1 and CD133) and the capacity to form mammospheres were consistent with those of the EMT-related markers. The orthotopic xenograft models further confirmed that the attenuation of stem cell traits after silencing FLI-1 decreased the ability of tumorigenesis. These results indicate that FLI-1 is a useful predictor of poor prognosis in patients with breast cancer. Furthermore, the preliminary exploration of metastatic mechanism in the patients with TNBC will provide a potential target to treat breast cancer in the near future.

Innate lymphoid cells (ILCs), so far studied mostly in mouse models, are important tissue-resident innate immune cells that play important roles in the colorectal cancer microenvironment and maintain mucosal tissue homeostasis. Plasmacytoid dendritic cells (pDCs) present complexity in various tumor types and are correlated with poor prognosis. pDCs can promote HIV-1-induced group 3 ILC (ILC3) depletion through the CD95 pathway. However, the role of ILC3s in human colon cancer and their correlation with other immune cells, especially pDCs, remain unclear.

Umifenovir, a broad-spectrum nonnucleoside antiviral drug, has a promising efficacy against coxsackievirus B4 (CVB4) infection, but its mechanism remains unclear. CVB4 is a common human single-stranded RNA virus that belongs to the Picornaviridae family and the Enterovirus genus. Enterovirus can cause severe diseases, such as meningitis, myocarditis, pancreatitis, insulin-dependent diabetes, and several other diseases, in both adults and children. We have previously demonstrated the critical role of interleukin 10 (IL-10) in promoting CVB4 infection and the downregulation of IL-10 by umifenovir. To further explore the underlying mechanisms of umifenovir, we characterized the epigenetic regulation of IL-10 in IL-10 knockout RAW264.7 cells and a BALB/c mouse splenocyte model. Mechanistically, we found that umifenovir inhibited CVB4-activated IL-10 by enhancing the methylation level of the repressive histones H3K9me3 and H3K27me3 while reducing the acetylation level of the activating histone H3K9ac in the promoter region of the IL-10 gene. Furthermore, using a chromosome conformation capture approach, we discovered that CVB4 infection activated the IL-10 gene by forming an intrachromosomal interaction between the IL-10 gene promoter and an intronic enhancer of the downstream MK2 (mitogen-activated protein kinase [MAPK]-activated protein kinase 2 [MAPKAPK2]) gene, a critical component of the p38-MAPK signaling pathway, which is required for IL-10 gene expression. However, umifenovir treatment abolished this spatial conformation and chromatin interaction, thus reducing the continuous expression of IL-10 and subsequent CVB4 replication. In conclusion, this study reveals a novel epigenetic mechanism by which umifenovir controls CVB4 infections, thus laying a theoretical foundation for therapeutic use of umifenovir. IMPORTANCE Viral infections are major threats to human health because of their strong association with a variety of inflammation-related diseases, especially cancer. Many antiviral drugs are performing poorly in treating viral infections. This is probably due to the immunosuppressive effect of highly expressed IL-10, which is caused by viral infection. Umifenovir is a broad-spectrum antiviral drug. Our recent studies showed that umifenovir has a significant inhibitory effect on CVB4 infection and can reduce IL-10 expression caused by CVB4. However, another antiviral drug, rupintrivir, showed good antiviral activity but had no effect on the expression of IL-10. This suggests that the regulation of IL-10 expression is a key part of the antiviral mechanism of umifenovir. Therefore, due to the dual function of the inhibition of CVB4 replication and the regulation of immune antiviral pathway, the mechanism of umifenovir is of great value to study.

The development of immune checkpoint inhibitors has made a significant breakthrough in the treatment of non-small-cell lung cancer (NSCLC). However, there remains a huge unmet clinical need for patients with acquired resistance after initial treatment response.

We did a meta-analysis to compare the efficacy and safety of neoadjuvant chemotherapy (NACT) followed by concurrent chemoradiotherapy (CCRT) versus CCRT with or without adjuvant chemotherapy (AC) for patients with locoregionally advanced nasopharyngeal carcinoma based on randomized controlled trials.

Kcnq1ot1 is a long noncoding ribonucleic acid (RNA; lncRNA) that participates in the regulation of genes within the Kcnq1 imprinting domain. Using a novel RNA-guided chromatin conformation capture method, we demonstrate that the 5' region of Kcnq1ot1 RNA orchestrates a long-range intrachromosomal loop between KvDMR1 and the Kcnq1 promoter that is required for maintenance of imprinting. PRC2 (polycomb repressive complex 2), which participates in the allelic repression of Kcnq1, is also recruited by Kcnq1ot1 RNA via EZH2. Targeted suppression of Kcnq1ot1 lncRNA prevents the creation of this long-range intrachromosomal loop and causes loss of Kcnq1 imprinting. These observations delineate a novel mechanism by which an lncRNA directly builds an intrachromosomal interaction complex to establish allele-specific transcriptional gene silencing over a large chromosomal domain.

Low-dose radiation (LDR) induces hormesis and adaptive response in normal cells but not in cancer cells, suggesting its potential protection of normal tissue against damage induced by conventional radiotherapy. However, the underlying mechanisms are not well established. We addressed this in the present study by examining the role of the ataxia telangiectasia mutated (ATM) signaling pathway in response to LDR using A549 human lung adenocarcinoma cells and HBE135-E6E7 (HBE) normal lung epithelial cells. We found that LDR-activated ATM was the initiating event in hormesis and adaptive response to LDR in HBE cells. ATM activation increased the expression of CDK4/CDK6/cyclin D1 by activating the AKT/glycogen synthase kinase (GSK)-3β signaling pathway, which stimulated HBE cell proliferation. Activation of ATM/AKT/GSK-3β signaling also increased nuclear accumulation of nuclear factor erythroid 2-related factor 2, leading to increased expression of antioxidants, which mitigated cellular damage from excessive reactive oxygen species production induced by high-dose radiation. However, these effects were not observed in A549 cells. Thus, the failure to activate these pathways in A549 cells likely explains the difference between normal and cancer cells in terms of hormesis and adaptive response to LDR.

To explore an optimal frequency of whole-body low-dose radiation (LDR) to protect the kidney from diabetes, type 1 diabetic mice were induced with multiple injections of low-dose streptozotocin in male C57BL/6J mice. Diabetic or age-matched normal mice received whole-body exposure to 12.5 or 25 mGy either every other day or weekly for 4 or 8 weeks. Diabetes decreased the urinary creatinine and increased the microalbumin in urine, renal accumulation of 3-nitrotyrosine and 4-hydroxynonenal, and renal expression of collagen IV and fibronectin. All these renal pathological and functional changes in diabetic mice were significantly attenuated by exposure to LDR at all regimens. However, whole-body exposure of diabetic mice to 25 mGy weekly and to 12.5 mGy every other day for 8 weeks provided a better prevention of diabetic nephropathy than other LDR regimens. Furthermore, whole-body exposure to 25 mGy weekly for 8 weeks showed no detectable effect on the kidney of normal mice, but whole-body exposure to normal mice at 12.5 mGy every other day for 8 weeks increased urinary microalbumin and renal expression of collagen IV and fibronectin. These results suggest that whole-body exposure to LDR at 25 mGy weekly is the optimal condition of LDR to protect the kidney from diabetes.

Background: Tyrosine kinase inhibitors (TKIs) are standard treatment options for non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations. Increasing clinical investigations have explored the value of EGFR-TKIs plus antiangiogenic drugs as the first-line treatment for EGFR-mutated NSCLC. Methods: We systematically searched PubMed, Cochrane Library, and EMBASE for randomized controlled trials (RCTs) investigating EGFR-TKIs administered with or without antiangiogenic agents for advanced EGFR-mutated NSCLC. The latest RCT that was presented orally at the 2019 European Society for Medical Oncology Congress was obtained online. The endpoints included progression-free survival (PFS), overall survival (OS), objective response rate (ORR), disease control rates (DCRs), and grade 3 or higher adverse events (AEs). Results: We included seven articles on five trials with 1,226 patients. The interventions for the experimental group were the first-generation EGFR-TKI erlotinib combined with bevacizumab (four studies) or ramucirumab (one study), and erlotinib monotherapy (four studies) or erlotinib plus placebo (one study) for the control group. All studies reached their primary study endpoints (i.e., PFS). Compared to erlotinib monotherapy, erlotinib plus antiangiogenic agents remarkably prolonged PFS [hazard ratio (HR) = 0.59, 95% confidence interval (CI) = 0.51-0.69, P = 0.000]; however, ORR, DCR, and OS were similar between the two groups. The overall grade 3-5 AEs increased in combination group (OR = 5.772, 95% CI = 2.38-13.94, P = 0.000), particularly the incidence of diarrhea (OR = 2.51, 95% CI = 1.21-5.23, P = 0.014), acneiform (OR = 1.815, 95% CI = 1.084-3.037, P = 0.023), hypertension (OR = 6.77, 95% CI = 3.62-12.66, P = 0.000), and proteinuria (OR = 13.48, 95% CI = 4.11-44.22, P = 0.000). Additionally, subgroup analysis demonstrated that Asian patients could significantly benefit from combination therapy (HR = 0.59, 95% CI = 0.50-0.69, P = 0.000). Patients with exon 19 deletions (HR = 0.61, 95% CI = 0.49-0.75, P = 0.000) and 21 Leu858Arg mutations (HR = 0.59, 95% CI = 0.47-0.73, P = 0.000) had almost equivalent PFS benefits when treated with double-blocking therapy. Patients with brain metastases at baseline in the combination group had a trend toward better PFS (HR = 0.55, 95% CI = 0.30-1.01, P = 0.001). Conclusions: Erlotinib plus bevacizumab or ramucirumab in EFGR-mutated NSCLC first-line setting yielded remarkable PFS benefits; however, this was accompanied by higher AEs. Epidermal growth factor receptor-TKI plus antiangiogenic agent therapy may be considered a new option for advanced EGFR-mutated NSCLC patients.