[Chemotherapy in gallbladder carcinoma]

Long non-coding RNA CRNDE promotes gallbladder carcinoma carcinogenesis and as a scaffold of DMBT1 and C-IAP1 complexes to activating PI3K-AKT pathway

Deleted in malignant brain tumors 1 (DMBT1) is deleted during cancer progression and as a potential tumor-suppressor gene in various types of cancer. However, its role in Gallbladder cancer remains poorly understood. DMBT1 has low-expression and deletion of copy number were detected in normal tissues and GBC cancer tissues by qRT-PCR. Knockdown of DMBT1 increased migration and invasion and overexpressed DMBT1 impaired migration and invasion in GBC cells. We also evaluated the molecular mechanism of DMBT1 by RNA sequencing and GSEA analysis. RNA-Pulldown and RIP assay authenticated CRNDE can specified binding with DMBT1 and c-IAP1. Downregulation of DMBT1 resulted in significant change of gene expression (at least 2-fold) in PI3K-AKT pathway, increased expression of MMP-9, JUK-1, ERK and AKT, activating PI3K-AKT pathway lead to GBC carcinogenesis.We for the first time reported, DMBT1 as a prognosis biomarker, is low-expressed in GBC tumors, and CRNDE act as a scaffold to recruit the DMBT1 and c-IAP1, promotes the PI3K-AKT pathway. Our study reveals DMBT1 may be an important contributor to GBC cancer development.

Oxymatrine induces apoptosis and inhibits invasion in Gallbladder carcinoma via PTEN/PI3K/AKT pathway

Oxymatrine extracted from Sophora flavescens Ait as a natural polyphenolic phytochemical has been demonstrated to exhibit anti-tumor effects on various cancers, including Gallbladder carcinoma (GBC). However, its underlying mechanisms of function are largely unknown in GBC cells. The present study is conducted to investigate the anti-tumor effects and the underlying mechanisms of oxymatrine on GBC cells in vitro and in vivo. The results showed that oxymatrine inhibited cell viability, metastatic ability and induced cell apoptosis in dose-dependent manners. Furthermore, we found that the expression of p-AKT, MMP-2, MMP-9 and the ratio of Bcl-2/Bax were significantly down-regulated, while the expression of PTEN was up-regulated in GBC cells. In addition, pretreatment with a specific PI3K/AKT activator (IGF-1) significantly antagonized the oxymatrine-mediated inhibition of GBC-SD cells. Subsequently, our in vivo studies showed that administration of oxymatrine induced a significant dose-dependent decrease in tumor growth. In conclusion, these findings indicated that the inhibition of cells proliferation, migration, invasion and the induction of apoptosis in response to oxymatrine in GBC cells, may function through the suppression of PTEN/PI3K/AKT pathway, which was considered as the vital signaling pathway in regulating tumorigenesis. These results suggested that oxymatrine might be a novel effective candidate as chemotherapeutic agent against GBC.

Study of Pemetrexed-based Chemotherapy for Patients with Locally Advanced or Metastatic Cancers

PURPOSE

This study was conducted to observe the efficacy and safety of pemetrexed based chemotherapy in treating patients with locally advanced or metastatic cancers as first-line, second-line or third-line therapy.

MATERIALS AND METHODS

From May 2011 to January 2015, we recruited 29 patients with advanced breast cancer, 19 patients with advanced ovary cancer, 17 patients with advanced esophageal cancer,5 patients with advanced gallbladder cancer,5 patients with advanced cervical cancer and 1 patient with advanced tongue cancer in Jiangsu Cancer Hospital and Research Institute.All of them were pathologically confirmed and treated with pemetrexed based chemotherapy. After two cycles of treatment,efficacy and safety can be evaluated.

RESULTS

For pemetrexed based regimens,including 76 patients with 6 kinds of advanced cancer were considered eligible for inclusion. Complete remission represents CR, partial remission represents PR, stable disease represents SD, progressive disease represents PD. Among 29 patients with advanced breast cancer, 4 patients chose pemetrexed based regimens as second-line treatment,1 of them was PR,the other 3 got SD. The last 25 patients made use of this chemotherapy as third-line treatment, except one patient could not be assessed, 2 of them got PR,6 of them got SD,the remaining 16 of them finally were PD.19 patients with advanced ovary cancer,5 patients used this regimens as second-line treatment, 3 of them got PD,the remaining patients got SD, respectively. The last 14 patients made use of pemetrexed based regimens as third-line treatment,. RR (CR+PR) was 28.5%. Among 17 patients with advanced esophageal cancer, 2 patients made use of pemetrexed based regimens as first-line treatment,both of them got PR.4 of them used this chemotherapy as second-line regimen, except 2 patients could not be assessed,the remaining 2 was PD at last. The last 11 patients was third-line users, RR (CR+PR) was 18.2%. Among 5 patients with advanced gallbladder cancer, pemetrexed based regimens was used in 1 patient as first- line treatment and 1 patient as second-line treatment. The curative effect was SD and PD, respectively. 3 patients accepted pemetrexed based regimens as third-line treatment, 2 of them got PD as results and another was SD. Among 5 patients with advanced cervical cancer, just 1 patient adopted pemetrexed based regimens as first-line treatment, whose curative effect was PR.2 patients chose this chemotherapy regimens as second-line treatment. Both of them got PD as their consequence. The last 2 patients made use of the regimens as third-line treatment, the effect of them was PD and SD, respectively. The one who with advanced tongue cancer, pemetrexed based regimens was used as second-line treatment, and the consequence was PD. About 71.1% patients experienced bone marrow suppression. Among them, 5 patients reached 4 grade. Other toxicity of pemetrexed were neurotoxicity, fatigue, diarrhea, dysphagia and vomiting. No treatment related death occurred with pemetrexed-based treatment.

CONCLUSIONS

Pemetrexed based chemotherapy has considerable effect in patients with advanced cancers such as breast cancer,esophageal cancer and ovary cancer. More randomly clinical trials are needed to verify the results.

Inhibition of mTOR pathway attenuates migration and invasion of gallbladder cancer via EMT inhibition

Gallbladder cancer (GBC) is an aggressive disease in which epithelial-mesenchymal transition (EMT) plays a critical role. Whether inhibition of mTOR effects via EMT reversal in GBC remains unclear. Using genetic and pharmacologic inhibitions of mTOR, we investigated the changes of EMT levels in GBC cells. Expressions of EMT related genes were also studied. Migration and invasion assays were carried out and in vivo tumour metastasis mouse models were established. Circulating tumour DNA was quantified. We used EMT index (ratio of Vimentin/Ecadherin expression) to profile EMT levels. We found that inhibition of mTOR using shRNAs and rapamycin inhibited EMT in GBC-SD gallbladder cancer cells. Inhibition of mTOR inhibited EMT in GBC-SD cells in TGF-β-dependent manner, which was contributed majorly by mTORC2 inhibition. Rapamycin decreased invasiveness and migration of GBC-SD cells in vitro and in vivo. We have in the current study shown that rapamycin diminishes the ability of invasion and migration of GBC via inhibition of TGF-β-dependent EMT. Our findings contribute to the understanding of the carcinogenesis of GBC.

Effect of circulating miR-141 on invasion and migration of gallbladder cancer cells

AIM: To screen differentially expressed microRNAs in serum and tissues of patients with gallbladder cancer and explore their effect on the migration and invasion ability of gallbladder cancer cells.

METHODS: The expression of 11 microRNAs was detected in serum of 12 patients with gallbladder cancer and 14 normal controls to screen differentially expressed microRNAs. Differential expression of screened microRNAs in human gallbladder cancer tissues was verified by real-time PCR. The effect of miR-141 mimic transfection on the invasion and migration ability of human gallbladder cancer GBC-SD cells was detected by Transwell assay and wound-healing assay.

RESULTS: Compared to the control group, two microRNAs (miR-141 and miR-200a) were significantly down-regulated, and one up-regulated in serum of patients with gallbladder cancer. The expression of miR-141 in human gallbladder cancer tissues was also significantly lower than that in normal gallbladder tissues (P < 0.05). Expression of miR-141 in human gallbladder cancer tissues was related with distant metastasis. The invasion and migration abilities of GBC-SD cells were declined after lentivirus-mediated miR-141 up-regulation.

CONCLUSION: Some microRNAs are differentially expressed in serum and tissues between patients with gallbladder cancer and healthy people. MiR-141 is probably involved in invasion and migration of gallbladder cancer.

Immunohistochemical expression of phospho-mTOR is associated with poor prognosis in patients with gallbladder adenocarcinoma

CONTEXT

Advanced gallbladder carcinoma (GBC) is a highly fatal disease with poor prognosis and few therapeutic alternatives. The mammalian target of rapamycin (mTOR) is a serine/threonine kinase that plays a central role in cell growth and homeostasis. Its regulation is frequently altered in various tumors and is an attractive target for cancer therapy; however, its status in GBC remains unclear.

OBJECTIVE

To characterize immunohistochemical expression and prognostic significance of phospho-mTOR in advanced gallbladder carcinoma.

DESIGN

Phospho-mTOR expression was examined by immunohistochemistry in tissue microarrays containing 128 advanced GBCs and 99 cases of chronic cholecystitis, which were divided into 2 groups according to the presence or absence of metaplasia. To evaluate the association of the level of phospho-mTOR expression with clinical variables and patient survival, the advanced GBCs were classified as having low or high expression. Statistical analysis was performed by using a significance level of P < .05, and Kaplan-Meier curves were constructed for survival analysis.

RESULTS

Immunostaining for phospho-mTOR was positive in 82 of 128 tumors (64.1%) and in 24% of chronic cholecystitis cases (16% nonmetaplasia and 32% with metaplasia) (P < .001). Survival analysis indicated that a high phospho-mTOR immunohistochemical expression was associated with poorer prognosis in patients with advanced GBC (P = .02).

CONCLUSIONS

Metaplasia is a common finding in chronic cholecystitis and is considered a precursor lesion of dysplasia. Our results suggest that the activation of mTOR occurs very early during the development of GBC, contributing to the carcinogenesis process. Phospho-mTOR expression is correlated with poor survival, supporting the potential of mTOR for targeted therapy.

Emodin as an effective agent in targeting cancer stem-like side population cells of gallbladder carcinoma

Side population (SP) cells are previously identified from bone marrow based on their capacity to efflux of the fluorescent dye Hoechst 33342. Recent studies demonstrate that SP cells isolated from various cancer cell lines and primary tumors possess stem-cell-like properties. Thus, targeting tumor SP cells may provide new strategies for treatment in clinic. We previously showed that 1,3,8-trihydroxy-6-methylanthraquinone (emodin), a reactive oxygen species (ROS) generator, enhanced sensitivity of gallbladder cancer SGC-996 cells to cisplatin (CDDP) via generation of ROS and downregulation of multidrug-resistance-associated protein 1 (MRP1). To determine whether emodin also acts effectively on cancer stem cells of gallbladder carcinoma, we use SP cells as a model of cancer stem-cell-like cells. Here, we found that emodin, via ROS-related mechanism and suppressing the function of ATP-binding cassette super-family G member (ABCG2), which is known to be associated with Hoechst dye efflux activity of SP cells, not only reduced the ratio, inhibited clone formation, and eliminated sphere formation of SP cells effectively, but also promoted obviously the intracellular accumulation of doxorubicin, the main substrate of the efflux pump ABCG2. In addition, emodin could sensitize CDDP, via inhibition of expression of ABCG2, to overcome chemoresistance of SP cells. Importantly, similar to the experiment in vitro, emodin/CDDP co-treatment in vivo suppressed the tumor growth derived from SP cells through downregulating ABCG2 expression. Our results suggest that emodin is an effective agent targeting cancer stem-like SP cells of gallbladder carcinoma, either alone or acts as a chemotherapy enhancer.