Long non-coding RNA DINO promotes cisplatin sensitivity in lung adenocarcinoma via the p53-Bax axis.

Background: The damage-induced non-coding (DINO) RNA is a newly identified long non-coding RNA (lncRNA) found in human cells with DNA damage. The treatment of tumors with cisplatin can induce DNA damage; however, whether the lncRNA DINO is involved in the treatment of non-small cell lung cancer (NSCLC) has not yet been elucidated. Methods: The expression of the lncRNA DINO in lung adenocarcinoma cells was detected using quantitative real-time polymerase chain reaction (qRT-PCR). The lung adenocarcinoma cell line, A549, and derived cisplatin-resistant cell line, A549R, were selected to construct cell models with lncRNA DINO overexpression or interference via lentiviral transfection. After cisplatin treatment, changes in the apoptosis rate were measured. Changes in the p53-Bax axis were detected by qRT-PCR and Western blot. Cycloheximide (CHX) interference demonstrated the stability of p53 with new protein production induced by the lncRNA DINO. The in vivo experiments involved intraperitoneal injection of nude mice with cisplatin after subcutaneous tumor formation, and the tumor diameters and weights were recorded. Immunohistochemistry and hematoxylin and eosin (H&E) staining were performed following tumor removal. Results: We found that the lncRNA DINO was significantly down-regulated in NSCLC. DINO overexpression enhanced the sensitivity of NSCLC cells to cisplatin, while DINO down-regulation decreased the sensitivity of NSCLC cells to cisplatin. Mechanistic investigation indicated that DINO enhanced the stability of p53 and mediated the activation of the p53-Bax signaling axis. Our results also demonstrated that the lncRNA DINO could partially reverse cisplatin resistance induced by silencing the p53-Bax axis, and could inhibit subcutaneous tumorigenesis in nude mice after cisplatin treatment in vivo. Conclusions: The lncRNA DINO regulates the sensitivity of lung adenocarcinoma to cisplatin by stabilizing p53 and activating the p53-Bax axis, and thus, may be a novel therapeutic target to overcome cisplatin resistance.

Chitosan-based nanoparticle co-delivery of docetaxel and curcumin ameliorates anti-tumor chemoimmunotherapy in lung cancer.

The application of traditional chemotherapy drugs for lung cancer has obvious limitations, such as toxic side effects, uncontrolled drug-release, poor bioavailability, and drug-resistance. Thus, to address the limitations of free drugs and improve treatment effects, we developed novel T7 peptide-modified nanoparticles (T7-CMCS-BAPE, CBT) based on carboxymethyl chitosan (CMCS), which is capable of targeted binding to the transferrin receptor (TfR) expressed on lung cancer cells and precisely regulating drug-release according to the pH value and reactive oxygen species (ROS) level. The results showed that the drug-loading content of docetaxel (DTX) and curcumin (CUR) was approximately 7.82% and 6.48%, respectively. Good biosafety was obtained even when the concentration was as high as 500 µg/mL. More importantly, the T7-CMCS-BAPE-DTX/CUR (CBT-DC) complexes exhibited better in vitro and in vivo anti-tumor effects than DTX monotherapy and other nanocarriers loaded with DTX and CUR alone. Furthermore, we determined that CBT-DC can ameliorate the immunosuppressive micro-environment to promote the inhibition of tumor growth. Collectively, the current findings help lay the foundation for combinatorial lung cancer treatment.

Circ-HMGA2 (hsa_circ_0027446) promotes the metastasis and epithelial-mesenchymal transition of lung adenocarcinoma cells through the miR-1236-3p/ZEB1 axis.

Lung adenocarcinoma (LUAD) has high incidence and mortality rates worldwide; however, its detailed molecular pathology remains unclear. Although circRNAs have gradually been identified as molecules that are differentially expressed in tumors and play key roles in tumor progression, their role in LUAD is poorly understood. Through microarray analysis, we obtained the circRNA expression profile of LUAD and found that circ-HMGA2 (hsa_circ_0027446), a novel RNA, is highly expressed in LUAD. The high expression of circ-HMGA2 was further verified in 36 paired LUAD and adjacent normal tissues. Functionally, circ-HMGA2 promoted LUAD cell metastasis in vitro and in vivo. The luciferase reporter assay and FISH results showed that circ-HMGA2 interacts with miR-1236-3p and that miR-1236-3p interacts with ZEB1. In addition, miR-1236-3p was expressed at low levels in LUAD, inhibited LUAD cell metastasis, and suppressed the function of circ-HMGA2. ZEB1 is an EMT-promoting transcription factor. The PCR and WB analysis results showed that circ-HMGA2 promotes both ZEB1 expression and EMT. MiR-1236-3p had the opposite effect, reversing the promotive effect of circ-HMGA2 on EMT. In summary, circ-HMGA2 promotes LUAD cell metastasis through the miR-1236-3p/EMT axis, indicating that it could be a therapeutic target in LUAD.

Combination effect of curcumin with docetaxel on the PI3K/AKT/mTOR pathway to induce autophagy and apoptosis in esophageal squamous cell carcinoma.

BACKGROUND: Docetaxel (DTX) is widely used to treat many malignant tumors but has many adverse effects. Curcumin (CUR) also has effects on a variety of tumor cells and can reduce the toxicity and side effects of chemotherapy drugs and the occurrence of drug resistance. However, the combination of CUR and DTX for treating esophageal cancer has not been reported. METHODS: Human esophageal squamous cell carcinoma (ESCC) KYSE150 and KYSE510 cells were treated with CUR or DTX alone or both drugs and cancer cell viability was detected by CCK8, apoptosis, scratch-healing and migration assays. Electron microscopy and Western blots were used. In vivo experiments were used observe anti-tumor effects. RESULTS: CUR combined with DTX significantly inhibited the viability and migration of esophageal cancer cells (P<0.01) and further promoted the apoptosis of cancer cells. In addition, CUR induced autophagy in esophageal cancer cells when combined with DTX. DTX combined with CUR may induce apoptosis and autophagy by inhibiting the PI3K/AKT/mTOR signaling pathway. The compound 3-methyladenine (3MA) inhibited the autophagy induced by DTX and CUR (DC), further accelerated apoptosis and inhibited the proliferation of esophageal cancer cells when combined with DC. CONCLUSION: CUR combined with DTX induced apoptosis and autophagy of ESCC and probably worked through the PI3K/AKT/mTOR signaling pathway. The combination of the autophagy inhibitor, CUR and DTX may become a new treatment strategy for esophageal cancer.

PLCD1 Suppressed Cellular Proliferation, Invasion, and Migration via Inhibition of Wnt/ß-Catenin Signaling Pathway in Esophageal Squamous Cell Carcinoma.

BACKGROUND: Phospholipase C delta 1 (PLCD1) has been found to be abnormally expressed in various cancers. However, the potential roles of PLCD1 in esophageal squamous cell carcinoma (ESCC) are still unknown. METHODS: Western blot and qPCR were used to explore PLCD1 expression in various ESCC cells. MTT, colony formation assays, wound-healing assay, and transwell cell invasion assay were used to examine the cell viability in vitro. Western blot, qPCR, and luciferase assays were used to investigate the effects of PLCD1 on Wnt/ß-catenin signaling pathway. The xenograft models in nude mice were established to explore the roles of PLCD1 in vivo. RESULTS: We found that the expression of PLCD1 in ESCC cells was significantly downregulated than that in normal esophageal epithelial cells. In addition, upregulation of PLCD1 decreased the capacity of TE-1 and EC18 cells in proliferation, invasion, and migration. Then, the expression of ß-catenin/p-ß-catenin, C-myc, cyclin D1, MMP9, and MMP7 was investigated. PLCD1 activity was found to be negatively associated with the expression of ß-catenin, C-myc, cyclin D1, MMP9, and MMP7. Finally, the activity of PLCD1 in inhibiting ESCC proliferation in vivo was validated. CONCLUSION: The inhibitory effects of PLCD1 on the proliferation, invasion, and migration of TE-1 and EC18 cells might be associated with inhibition of Wnt/ß-catenin signaling pathway. PLCD1 played a key role in inhibiting ESCC carcinogenesis and progression in patients with ESCC.

Novel T7-Modified pH-Responsive Targeted Nanosystem for Co-Delivery of Docetaxel and Curcumin in the Treatment of Esophageal Cancer.

BACKGROUND: Although single-drug chemotherapy is still an effective treatment for esophageal cancer, its long-term application is limited by severe side-effects, poor bioavailability, and drug-resistance. Increasing attention has been paid to nanomedicines because of their good biological safety, targeting capabilities, and high-efficiency loading of multiple drugs. Herein, we have developed a novel T7 peptide-modified pH-responsive targeting nanosystem co-loaded with docetaxel and curcumin for the treatment of esophageal cancer. METHODS: Firstly, CM-ß-CD-PEI-PEG-T7/DTX/CUR (T7-NP-DC) was synthesized by the double emulsion (W/O/W) method. The targeting capacity of the nanocarrier was then investigated by in vitro and in vivo assays using targeted (T7-NP) and non-targeted nanoparticles (NP). Furthermore, the anti-tumor efficacy of T7-NP-DC was studied using esophageal cancer cells (KYSE150 and KYSE510) and a KYSE150 xenograft tumor model. RESULTS: T7-NP-DC was synthesized successfully and its diameter was determined to be about 100 nm by transmission electron microscopy and dynamic light scattering. T7-NP-DC with docetaxel and curcumin loading of 10% and 6.1%, respectively, had good colloidal stability and exhibited pH-responsive drug release. Good biosafety was observed, even when the concentration was as high as 800 µg/mL. Significant enhancement of T7-NP uptake was observed 6 hours after intravenous injection compared with NP. In addition, the therapeutic efficacy of T7-NP-DC was better than NP-DC and docetaxel in terms of growth suppression in the KYSE150 esophageal cancer model. CONCLUSION: The findings demonstrated that T7-NP-DC is a promising, non-toxic, and controllable nanoparticle that is capable of simultaneous delivery of the chemotherapy drug, docetaxel, and the Chinese Medicine, curcumin, for treatment of esophageal cancer. This novel T7-modified targeting nanosystem releases loaded drugs when exposed to the acidic microenvironment of the tumor and exerts a synergistic anti-tumor effect. The data indicate that the nanomaterials can safely exert synergistic anti-tumor effects and provide an excellent therapeutic platform for combination therapy of esophageal cancer.

KLK11 suppresses cellular proliferation via inhibition of Wnt/ß-catenin signaling pathway in esophageal squamous cell carcinoma.

Studies have demonstrated that kallikrein-associated peptidase 11 (KLK11) is dysregulated in various cancers. However, the potential roles of KLK11 in esophageal squamous cell carcinoma (ESCC) are still unknown. In our study, we found that the expression of KLK11 in advanced ESCC was significantly down regulated than that in the adjacent tissues, and patients with higher KLK11 expression had markedly increased overall survival rates compared with those with lower KLK11 expression. In addition, up regulation of KLK11 decreased the proliferation capacity of TE-1 and EC18 cells, and down regulation of KLK11 increased the proliferation capacity. To explore the possible mechanism of KLK11 in regulating the proliferation of ESCC, the expression of the related factors in Wnt/ß-catenin pathway and cell cycle-mediated factors, such as GSK-3ß/p-GSK-3ß, ß-catenin, Ki67, p-Rb/Rb, CDK6, CDK4 and Cyclin D1, were determined. Furthermore, KLK11 was found to be negatively correlated with the expression of ß-catenin in the nucleus, as showed by decreased expression of cyclin D1 and Ki67 through deactivation of the Wnt/ß-catenin signaling pathway. XAV-939, a Wnt/ß-catenin inhibitor, partially decreased the effects of KLK11 deficiency on ESCC cell proliferation. Finally, we validated that KLK11 inhibited ESCC proliferation in vivo. Our results showed that the inhibitory effects of KLK11 on the proliferation of TE-1 and EC18 cells might be associated with inhibition of Wnt/ß-catenin signaling pathway. KLK11 played a key role in inhibiting ESCC carcinogenesis and progression and became a potential biomarker for poor prognosis in patients with ESCC.

Babaodan inhibits cell growth by inducing autophagy through the PI3K/AKT/mTOR pathway and enhances antitumor effects of cisplatin in NSCLC cells.

Babaodan capsule (BBD), a traditional Chinese (TCM) formula, has been widely used as an alternative remedy for multiple types of malignancies, clinically. However, the underlying mechanisms behind the efficacy of BBD remain poorly understood, particularly in regard to lung cancer. Herein, we demonstrate that BBD induced autophagic death in A549 and A549DDP cells without apoptosis. Treatment with autophagic inhibitor 3-MA, Baf-A1 and PI3K agonist, IGF-1, fully proved our conclusion, as well as uncovered the potential downregulated signaling pathway, PI3K/AKT/mTOR. The study additionally found that BBD could downregulate the expression of MDR1 and increase the chemosensitivity of cisplatin. Collectively, our results, both in vivo and in vitro, demonstrate that BBD leads to autophagic cell death through downregulating the PI3K/AKT/mTOR signaling pathway and improved the antitumor effects of cisplatin in non-small cell lung cancer (NSCLC).

Elevated levels of hsa_circ_006100 in gastric cancer promote cell growth and metastasis via miR-195/GPRC5A signalling.

OBJECTIVES: Circular RNAs (circRNAs) are non-coding RNAs, some of which are thought to be involved in gastric cancer development. Here, we examined the functions of circRNA hsa_circ_006100 in gastric cancer cells and an animal model of gastric cancer. MATERIALS AND METHODS: The expression of hsa_circ_006100, miR-195 and various functional genes was determined by quantitative RT-PCR. Cell viability, clone formation, apoptosis and cell migration/invasion abilities were analysed by the CCK-8 assay, crystal violet staining, Hoechst staining and Transwell assay, respectively. A tumour model was established by subcutaneously injecting tumour cells into nude mice. Levels of protein expression were analysed by Western blotting and immunohistochemistry. RESULTS: A bioinformatics analysis showed that miR-195 was negatively co-expressed with hsa_circ_006100. Patients with a high hsa_circ_006100 level or low miR-195 level had tumours with a high TNM stage, poor cellular differentiation and lymph node metastasis. miR-195 was targeted and inhibited by hsa_circ_006100. Overexpression of hsa_circ_006100 enhanced cellular viability and proliferation, while miR-195 suppressed hsa_circ_006100-enhanced cell growth and induced apoptosis in MGC-803 and AGS cells. Forced hsa_circ_006100 expression promoted the migration and invasion of MGC-803 and AGS cells, while those activities were inhibited by miR-195. Mechanistically, GPRC5A was predicted as a target of miR-195 and was upregulated in gastric cancer. A miR-195 inhibitor restored cell viability, proliferation, migration and invasion, and repressed apoptosis via GPRC5A. In vivo studies showed that knockdown of hsa_circ_006100 delayed tumour growth, reduced PCNA expression and upregulated miR-195 and BCL-2 expression which was restored by miR-195 inhibition due to GPRC5A/EGFR signalling, and changed the EMT phenotype in vivo. CONCLUSIONS: Hsa_circ_006100 functions as an oncogene in gastric cancer and exerts its effects via miR-195/GPRC5A signalling.

MicroRNA-497 accelerates apoptosis while inhibiting proliferation, migration, and invasion through negative regulation of the MAPK/ERK signaling pathway via RAF-1.

The aim of this study is to explore the various modes of action miR-497 has on human cervical cancer (CC) cell behavior. We also speculate that miR-497 achieves its anti-tumor role by governing RAF-1 via MAPK/ERK signaling pathway. CC tissues with corresponding adjacent normal tissues were collected from 168 CC patients. RAF-1-positive cells were identified by means of immunohistochemistry in tissues. A series of inhibitors, mimics and siRNA against RAF-1 were introduced to validate regulatory mechanisms for miR-497 and RAF-1. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot assay were employed for evaluating alternations of miR-497, RAF-1, and MAPK/ERK signaling pathway. HeLa cell proliferation, invasion, migration, cycle progression, and apoptosis were assessed by means of CCK-8, wound-healing, transwell invasion assays, and flow cytometry, respectively. The target prediction program and luciferase activity determination were used to identify miR-497 targeting RAF-1. We determined reduced miR-497 expression and elevated expression of RAF-1 in CC tissues as opposed to adjacent tissues. Transfection of miR-497 mimics and siRNA-RAF-1 both decreased levels of MEK1, ERK1, and p38 phosphorylation in HeLa cells, inhibited cell proliferation, migration and invasion, induced more cells arrested in the G0/G1 phase, and promoted cell apoptosis; while miR-497 inhibitors led to opposite results. These findings indicate miR-497 as a tumor suppressor results from negative regulation of the MAPK/ERK signaling pathway via RAF-1 in CC.

The association of tea consumption with bladder cancer risk: a meta-analysis.

The association between tea consumption and bladder cancer has been confirmed in several animal studies, but one epidemiological study in 2001 showed no association between them. In order to provide an accurate assessment of this, we conducted a meta-analysis on tea consumption and bladder cancer risk. Studies were identified by a literature search in PubMed from January 1980 to March 2012 and the reference lists of relevant studies. Random effect models were used to calculate summary relative risk estimates (RR) and their corresponding 95% confidence intervals (CI) based on high contrast to low intake values. Twenty-four publications (6 cohort studies and 18 case-control studies) based on consumption of overall tea, black tea, and green tea to bladder cancer risk were included in this analysis. For overall tea, the summary RR indicated no association between tea consumption and bladder cancer (RR= 1.09, 95%CI: 0.85-1.40). In subgroup analyses, we found a moderate increase of bladder cancer risk in smoking group (RR= 1.77, 95%CI: 1.04-3.01). In the black tea group, no statistically significant association was observed (RR= 0.84, 95%CI: 0.70-1.01). Interestingly, in the subgroup of sex, a protective effect was observed between tea consumption and bladder cancer risk in female (RR= 0.61, 95%CI: 0.38- 0.98). For green tea group, there was no relationship associated with bladder cancer risk (RR= 1.03, 95%CI: 0.82- 1.31). In conclusion, our data suggest that high overall tea intake in smokers increased the risk of bladder cancer, and high black tea intake in female may reduce the risk of bladder cancer.