Baoen Shan

The lncRNA SNHG5/miR-32 axis regulates gastric cancer cell proliferation and migration by targeting KLF4

Long noncoding RNAs (lncRNAs) are emerging as important regulators in cellular processes, including the development, proliferation, and migration of cancer cells. We have demonstrated in a prior study that small nucleolar RNA host gene 5 (SNHG5) is dysregulated in gastric cancer (GC). To further explore the underlying mechanisms of SNGH5 function in the development of GC, in this study, we screened the microRNAs interacting with SNHG5 and elucidated their roles in GC. We showed that SNHG5 contains a putative miR‐32‐binding site and that deletion of this site abolishes the responsiveness to miR‐32. Suppression of SNHG5 expression by miR‐32 was found to be Argonaute (Ago)2‐dependent. Immunoprecipitation showed that SNHG5 could be pulled down from the Ago‐2 complex with miR‐32. Furthermore, it was reported that Kruppel‐like factor 4 (KLF4) is a target gene of miR‐32. In agreement with SNHG5 being a decoy for miR‐32, we showed that KLF4 suppression by miR‐32 could be partially rescued by SNHG5 overexpression, whereas miR‐32 mimic rescued SNHG5 overexpression‐mediated suppression of GC cell migration. In addition, we identified a negative correlation between the expression of SNHG5 and miR‐32 in GC tissues. Furthermore, KLF4 expression was significantly downregulated in GC specimens, and a negative correlation between miR‐32 and KLF4 expression and a positive correlation between KLF4 and SNHG5 expression levels were detected. Overall, this study demonstrated, for the first time, that the SNHG5/miR‐32/KLF4 axis functions as an important player in GC cell migration and potentially contributes to the improvement of GC diagnosis and therapy.—Zhao, L., Han, T., Li, Y., Sun, J., Zhang, S., Liu, Y., Shan, B., Zheng D., Shi, J. The lncRNA SNHG5/miR‐32 axis regulates gastric cancer cell proliferation and migration by targeting KLF4. FASEB J. 31, 893–903 (2017). www.fasebj.org

Leptin promotes metastasis by inducing an epithelial-mesenchymal transition in A549 lung cancer cells.

Leptin, an adipocyte-derived cytokine associated with obesity, has been reported to participate in carcinogenesis. Epithelial-mesenchymal transition (EMT) is also considered as a key event in tumor metastasis. The aim of this study is to investigate the mechanism of leptin in the promotion of EMT leading to metastasis in A549 lung cancer cells. We investigated the effect of leptin on migration of A549 cells using wound healing and transwell assays. The incidence of EMT in A549 cells was examined by real-time PCR and immunofluorescence staining. The expression of TGF-β in A549 cells was detected by real-time PCR, and blocking of TGF-β in A549 cells was achieved by siRNA techniques. Additional work was performed using 100 patient samples, which included samples from 50 patients diagnosed with lung cancer and an additional 50 patients diagnosed with lung cancer with metastatic bone lesions. Leptin expression was measured using immunohistochemistry techniques. We demonstrated that leptin can effectively enhance the metastasis of human lung cancer A549 cell line using both wound healing and transwell assays. We also found the incidence of EMT in A549 cells after leptin exposure. Furthermore, we detected the expression of TGF-β in A549 cells, which had been reported to play an important role in inducing EMT. We showed that leptin can significantly upregulate TGF-β at both the mRNA and protein levels in A549 cells. Using siRNA to block the expression of TGF-β in A549 cells, we confirmed the role of TGF-β in the promotion of metastasis and induction of EMT. Furthermore, we found that in patient samples leptin was present at higher levels in samples associated with diagnosis of lung cancer bone metastases tissue than lung cancer tissue. Our results indicated that leptin promoted the metastasis of A549 human lung cancer cell lines by inducing EMT in a TGF-β-dependent manner.

Ethanol extract of Forsythia suspensa root induces apoptosis of esophageal carcinoma cells via the mitochondrial apoptotic pathway

Forsythia suspensa root is used in the treatment of fever and jaundice in Traditional Chinese Medicine. In the present study, the anti-tumor activity of the ethanolic extract of Forsythia suspensa root (FSREE) against esophageal carcinoma cells was investigated in vitro and in vivo and its anti-cancer mechanism was examined. The results revealed that FSREE, rather than Forsythia suspensa ethanolic extracts from the leaf (FSLEE) and fruit (FSFEE) exhibited marked anti-tumor activity towards human esophageal cancer cells. FSREE induced cancer cell apoptosis and growth arrest by downregulating B-cell lymphoma (Bcl)-2, Bcl-extra large and myeloid cell leukemia 1, while upregulating Bcl-2-associated X protein, Bcl-2 antagonist of cell death and phorbol-12-myristate-13-acetate-induced protein 1. This led to the activation of poly(ADP ribose) polymerase, caspase-3 and caspase-9, but not caspase-8. Furthermore, the anti-cancer activity of FSREE was associated with a decreased level of phosphorylated Janus kinase/signal transducer and activator of transcription 3 and extracellular-signal-regulated kinase signaling activity. It was also observed that the levels of cytochrome c were elevated in the cytoplasm, accounting for the loss of mitochondrial membrane potential in the TE-13 cells upon treatment with FSEER. In addition, FSEER inhibited the growth of esophageal cancer cells in xenograft models and no detectable toxicity was present in the lung or liver tissues. These observations provided further evidence of the anti-tumor effect of FSEER and may be of importance to further examine the potential role of Forsythia suspensa root as a therapeutic agent in esophageal carcinoma therapy.

An ester extract of Cochinchina momordica seeds induces differentiation of melanoma B16 F1 cells via MAPKs signaling.

Cochinchina momordica seeds (CMS) have been widely used due to antitumor activity by Mongolian tribes of China. However, the details of the underlying mechanisms remain unknown. In the present study, we found that an EtOAc (ethyl ester) extract of CMS (CMSEE) induced differentiation and caused growth inhibition of melanoma B16 F1 cells. CMSEE at the concentration of 5-200 μg/ml exhibited strongest anti-proliferative effects on B16 F1 cells among other CMS fractions (water or petroleum ether). Moreover, CMSEE induced melanoma B16 F1 cell differentiation, characterized by dendrite-like outgrowth, increasing melanogenesis production, as well as enhancing tyrosinase activity. Western blot analysis showed that sustained phosphorylation of p38 MAP accompanied by decrease in ERK1/2 and JNK dephosphorylation were involved in CMSEE-induced B16 F1 cell differentiation. Notably, 6 compounds that were isolated and identified may be responsible for inducing differentiation of CMSEE. These results indicated that CMSEE contributes to the differentiation of B16 F1 cells through modulating MAPKs activity, which may throw some light on the development of potentially therapeutic strategies for melanoma treatment.

Incidence and mortality rate of esophageal cancer has decreased during past 40 years in Hebei Province, China

BACKGROUNDnHebei province is located in North of China with of approximately 6% of whole national population. It is known as a high-risk area for esophageal cancer in China and worldwide. The aim of our study was to estimate the esophageal cancer burden and trend in Hebei Province.nnnMETHODSnEight cancer registries in Hebei Province submitted cancer registry data to the Hebei Provincial Cancer Registry Center. All data were qualified and compiled for cancer statistics in 2011. The pooled data were stratified by gender and age group (0, 1-4, 5-9, 10-14…80+). Incidence and mortality rates were age-standardized to World Segis population standard and expressed per 100,000 persons. In addition, proportions and cumulative incidence/mortality rates for esophageal cancer were calculated. Esophageal cancer mortality data during the periods 1973-1975, 1990-1992, and 2004-2005 were extracted from the national death surveys. Mortality and incidence rate data from Cixian and Shexian were obtained from population-based cancer registries in each county.nnnRESULTSnThe estimated number of newly diagnosed esophageal cancer cases and deaths in 2011 in Hebei Province was 24,318 and 18,226, respectively. The crude incidence rate of esophageal cancer was 33.37/100,000 (males, 42.18/100,000 and females, 24.31/100,000). The age-standardized rate by world standard population (ASRW) was 28.09/100,000, ranking third among all cancers. The esophageal cancer mortality rate was 25.01/100,000 (males, 31.40/100,000 and females, 18.45/100,000), ranking third in deaths among all cancers. The mortality rates of esophageal cancer displayed a significant decreasing trend in Hebei Province from 1973-1975 (ASRW =48.69/100,000) to 2004-2005 (ASRW =28.02/100,000), with a decreased rate of 42.45%. In Cixian, the incidence of esophageal cancer decreased from 250.76/100,000 to 106.74/100,000 in males and from 153.86/100,000 to 75.41/100,000 in females, with annual percentage changes (APC) of 2.13 and 2.16, while the mortality rates declined with an APC of 2.46 for males and 3.10 for females from 1988 to 2011. In Shexian, the incidence rate decreased from 116.90/100,000 to 74.12/100,000 in males and from 46.98/100,000 to 40.64/100,000 in females, while the mortality rates declined, with an APC of 4.89 in males from 2003 to 2011.nnnCONCLUSIONSnAlthough the incidence and mortality rates of esophageal cancer remain high, an obvious decreasing trend has been observed in Hebei Province, as well as in high-risk regions, such as Cixian and Shexian, over the past 40 years.

Nerve growth factor and receptors are significantly affected by histamine stimulus through H1 receptor in pancreatic carcinoma cells

Nerve growth factor (NGF) as an autocrine or paracrine growth factor plays a critical role in the pathogenesis and progression of human pancreatic cancer. NGF is synthesized as a proform (proNGF) that, when cleaved, releases mature ligand (mNGF). proNGF and mNGF bind to high-affinity tyrosine kinase receptor A (TrkA) and low-affinity receptor p75 to different extents. Histamine is a potent stimulator of NGF in the inflammatory lesion as determined by ELISA. This has generally been attributed to the accumulation of mNGF. To determine the effect of histamine on nerve growth factor/receptor expression in human pancreatic cancer, the present study explored intracellular and extracellular NGF production and p75 and TrkA membrane receptor expression in the PANC-1, KMP-6 and PK-1 cell lines. Histamine enhanced NGF secretion and mRNA expression in PANC-1 and KMP-6 cells, but not in PK-1 cells. proNGF was revealed using Western blotting to be the predominant form of NGF, but was significantly reduced by histamine. p75 receptor binding was increased with histamine treatement, but no significant alteration was observed for TrkA. Proliferating cell nuclear antigen (PCNA), an important indicator of cell proliferation, was significantly reduced by histamine stimulation. H1 and H2 receptors were both observed in the pancreatic cancer cells, and the alterations induced by histamine were counteracted by H1 receptor antagonist pyrilamine; however, the H2 receptor subtype was excluded from this process. These results suggest that histamine induces distinct nerve growth factor/receptor responsiveness via H1 receptor-induced signaling, thus affecting pancreatic cancer cell proliferation.

Incidence and risk of treatment-related mortality with anti-epidermal growth factor receptor monoclonal antibody in cancer patients: a meta-analysis of 21 randomized controlled trials.

Background Anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (MoAbs) cetuximab and panitumumab have emerged as an effective targeted therapy in the treatment of cancer patients, but the overall incidence and risk of fatal adverse events (FAEs) associated with these agents is still unclear. Methods Databases from PubMed, Web of Science and abstracts presented at ASCO meeting up to May 31, 2013 were searched to identify relevant studies. Eligible studies included prospective randomized controlled trials evaluating MoAbs in cancer patients with adequate data on FAEs. Statistical analyses were conducted to calculate the summary incidence, odds ratio and 95% confidence intervals (CIs) by using either random effects or fixed effect models according to the heterogeneity of included studies. Results A total of 14,776 patients with a variety of solid tumors from 21 clinical trials were included in our analysis. The overall incidence of MoAbs associated FAEs was 1.7% (95%CI: 1.1–2.5%), and the incidence of cetuximab-related FAEs was higher than that of panitumumab (2.0% versus 0.9%). Compared with the controls, the use of MoAbs was associated with a significantly increased risk of FAEs, with an OR of 1.37 (95%CI: 1.04–1.81, p=0.024). Subgroup analysis based on EGFR-MoAbs drugs, phase of trials and tumor types demonstrated a tendency to increase the risk of FAEs, but the risk did not increase in breast cancer, esophagus cancer and phase II trials. Conclusions With present evidence, the use of EGFR-MoAbs is associated with an increased risk of FAEs in patients with advanced solid tumors.

A high cholesterol diet given to apolipoprotein E-knockout mice has a differential effect on the various neurotrophin systems in the hippocampus

Apolipoprotein E (apoE) is one of the major transporters of cholesterol in the body and is essential for maintaining various neural functions in the brain. Given that hypercholesterolemia is a risk factor in Alzheimer’s disease (AD), it has been suggested that altered cholesterol metabolism may be involved in the development of the pathogenesis, including neural degeneration, commonly observed in AD patients. Neurotrophic factors and their receptors, which are known to regulate various neural functions, are also known to be altered in various neurodegenerative diseases. We therefore hypothesized that cholesterol metabolism may itself influence the neurotrophin system within the brain. We decided to investigate this possibility by modulating the amount of dietary cholesterol given to apoE-knockout (apoE-KO) and wild-type (WT) mice, and examining the mRNA expression of various neurotrophin ligands and receptors in their hippocampal formations. Groups of eight-week-old apoE-KO and WT mice were fed a diet containing either “high” (HCD) or “normal” (ND) levels of cholesterol for a period of 12xa0weeks. We found that high dietary cholesterol intake elevated BDNF mRNA expression in both apoE-KO and WT mice and TrkB mRNA expression in apoE-KO animals. On the other hand, NGF and TrkA mRNA levels remained unchanged irrespective of both diet and mouse type. These findings indicate that altered cholesterol metabolism induced by HCD ingestion combined with apoE deficiency can elicit a differential response in the various neurotrophin ligand/receptor systems in the mouse hippocampus. Whether such changes can lead to neural degeneration, and the mechanisms that may be involved in this, awaits further research.

Evaluation of miR-21 and miR-375 as prognostic biomarkers in oesophageal cancer in high-risk areas in China

MicroRNAs have been associated with prognosis in oesophageal cancer (EC), suggesting that miRNAs could play a role in guiding treatment decisions. The aim of this study was to evaluate the prognostic potential of miRNAs found to be associated with zinc deficiency in a geographical area with a high incidence of EC. miRNAs found to be associated with zinc deficiency were isolated from EC cell lines cultured with various Zn levels. The expression levels of the miRNAs were quantified using qRT-PCR. The potential prognostic value of the selected miRNAs was assessed in a cohort study of 88 patients from an area in China with a high incidence of EC. Correlations between miRNAs and patient characteristics were assessed using χ2 statistical tests or Fisher’s exact test. A Cox proportional hazards model was used to assess the correlations between miRNAs and overall survival (OS). Forest plots were performed to evaluate the prognostic impact of the miRNAs examined in the present study in the Asian population. The expression levels of miR-21, miR-31, miR-93 and miR-375 were different when Zn levels were varied in EC cell lines, but only miR-21 and miR-375 were associated with patient characteristics and prognosis in patients with EC from an area of China with a high incidence of EC. The patients expressing high levels of miR-21 had poor OS (HR 2.15, 95% CI 1.16–3.97), whereas those with high levels of miR-375 had improved OS (HR 0.47, 95% CI 0.26–0.87).The patients with both a high level of miR-375 and a low level of miR-21 had significantly better outcomes. Forest plots based on an analysis of this Asian population indicated that a high level of miR-21 significantly predicted a shortened OS (HR 1.83, 95% CI 1.42–2.37), whereas a high level of miR-375 was significantly correlated with increased survival (HR 0.56, 95% CI 0.43–0.73). MiR-21 and miR-375 could be used as prognostic biomarkers in areas with a high incidence of EC, and combining these markers may results in a better effect.

Bortezomib prevents oncogenesis and bone metastasis of prostate cancer by inhibiting WWP1, Smurf1 and Smurf2

Prostate cancer is the most common malignancy diagnosed in males, and bone metastases remain a significant source of morbidity and mortality in this population. Ubiquitin ligase E3s and proteasomes were thought to play essential roles in the development of cancers, therefore, they were proposed as therapy targets for the treatment of solid and hematological malignancies. Bortezomib, well-known as a proteasome inhibitor, has been observed with exact anticancer effect both in cell and animal models for several solid tumor types, including prostate cancer. To explore activities of the ubiquitin ligase E3s WWP1, Smurf1 and Smurf2 in oncogenesis and bone metastasis of prostate cancer, asxa0wellxa0as in the functional mechanism of bortezomib in preventing prostate cancer, transcription and expression levels of WWP1, Smurf1 and Smurf2 genes in cell lines or tissues of benign prostate hyperplasia and human prostate cancer with and without bone metastasis were tested. Moreover, human prostate cancer PC3 cell lines were treated with bortezomib at different concentration gradients and then their proliferation at different time points, mRNA and protein levels were investigated. The results indicated that transcription and expression levels of WWP1, Smurf1 and Smurf2 genes in prostate cancer without bone metastasis were significantly higher compared to those in benign prostate hyperplasia (P<0.05), whereas significantly lower than prostate cancer metastatic to bone (P<0.05). Furthermore, bortezomib reduced the transcription and expression levels of WWP1, Smurf1 and Smurf2 genes in prostate cancer cell lines in a dose-dependent manner, thus, inhibiting the proliferation of prostate cancer cells. Elevated transcription and expression levels of ubiquitin ligase E3s WWP1, Smurf1 and Smurf2 genes may be the mechanisms of occurrence, development and metastasis of prostate cancer. In addition, bortezomib can prevent prostate cancer and its bone metastasis by downregulating WWP1, Smurf1 and Smurf2.