TIGAR knockdown enhanced the anticancer effect of aescin via regulating autophagy and apoptosis in colorectal cancer cells.

Our previous study showed that TP53-induced glycolysis and apoptosis regulator (TIGAR) regulated ROS, autophagy, and apoptosis in response to hypoxia and chemotherapeutic drugs. Aescin, a triterpene saponin, exerts anticancer effects and increases ROS levels. The ROS is a key upstream signaling to activate autophagy. Whether there is a crosstalk between TIGAR and aescin in regulating ROS, autophagy, and apoptosis is unknown. In this study, we found that aescin inhibited cell viability and colony formation, and induced DNA damage, cell cycle arrest, and apoptosis in cancer cell lines HCT-116 and HCT-8 cells. Concurrently, aescin increased the expression of TIGAR, ROS levels, and autophagy activation. Knockdown of TIGAR enhanced the anticancer effects of aescin in vitro and in vivo, whereas overexpression of TIGAR or replenishing TIGAR downstream products, NADPH and ribose, attenuated aescin-induced apoptosis. Furthermore, aescin-induced ROS elevation and autophagy activation were further strengthened by TIGAR knockdown in HCT-116 cells. However, autophagy inhibition by knockdown of autophagy-related gene ATG5 or 3-methyladenine (3-MA) exaggerated aescin-induced apoptosis when TIGAR was knocked down. In conclusion, TIGAR plays a dual role in determining cancer cell fate via inhibiting both apoptosis and autophagy in response to aescin, which indicated that inhibition of TIGAR and/or autophagy may be a junctional therapeutic target in treatment of cancers with aescin.

Rottlerin upregulates DDX3 expression in hepatocellular carcinoma.

Rottlerin has been reported to exert its anti-tumor activity in various types of human cancers. However, the underlying molecular mechanism has not been fully elucidated. In the current study, we explored whether rottlerin exhibits its tumor suppressive function in hepatocellular carcinoma cells. Our MTT assay results showed that rottlerin inhibited cell growth in hepatocellular carcinoma cells. Moreover, we found that rottlerin induced cell apoptosis and caused cell cycle arrest at G1 phase. Furthermore, our wound healing assay result demonstrated that rottlerin retarded cell migration in hepatocellular carcinoma cells. Additionally, rottlerin suppressed cell migration and invasion. Notably, we found that rottlerin upregulated DDX3 expression and subsequently downregulated Cyclin D1 expression and increased p21 level. Importantly, down-regulation of DDX3 abrogated the rottlerin-mediated tumor suppressive function, whereas overexpression of DDX3 promoted the anti-tumor activity of rottlerin. Our study suggests that rottlerin exhibits its anti-cancer activity partly due to upregulation of DDX3 in hepatocellular carcinoma cells.

Aescin-induced reactive oxygen species play a pro-survival role in human cancer cells via ATM/AMPK/ULK1-mediated autophagy.

Aescin, a natural mixture of triterpene saponins, has been reported to exert anticancer effect. Recent studies show that aescin increases intracellular reactive oxygen species (ROS) levels. However, whether the increased ROS play a role in the anticancer action of aescin remains to be explored. In this study, we demonstrated that aescin (20-80 µg/mL) dose-dependently induced apoptosis and activated mammalian target of rapamycin (mTOR)-independent autophagy in human hepatocellular carcinoma HepG2 cells and colon carcinoma HCT 116 cells. The activation of autophagy favored cancer cell survival in response to aescin, as suppression of autophagy with ATG5 siRNAs or 3-methyladenine (3-MA), a selective inhibitor of autophagy, promoted aescin-induced apoptosis in vitro, and significantly enhanced the anticancer effect of aescin in vivo. Meanwhile, aescin dose-dependently elevated intracellular ROS levels and activated Ataxia-telangiectasia mutated kinase/AMP-activated protein kinase/UNC-51-like kinase-1 (ATM/AMPK/ULK1) pathway. The ROS and ATM/AMPK/ULK1 pathway were upstream modulators of the aescin-induced autophagy, as N-acetyl-L-cysteine (NAC) or ATM kinase inhibitor (KU-55933) remarkably suppressed aescin-induced autophagy and consequently promoted aescin-induced apoptosis, whereas overexpression of ATG5 partly attenuated NAC-induced enhancement in aescin-induced apoptosis. In conclusion, this study provides new insights into the roles of aescin-mediated oxidative stress and autophagy in cancer cell survival. Our results suggest that combined administration of the antioxidants or autophagic inhibitors with aescin might be a potential strategy to enhance the anticancer effect of aescin.

Transcription factor EB is involved in autophagy-mediated chemoresistance to doxorubicin in human cancer cells.

Transcription factor EB (TFEB) is a master regulator of autophagy activity and lysosomal biogenesis, but its role in autophagy-mediated cell survival and chemotherapy resistance is not completely understood. In this study, we explored whether TFEB played an important role in autophagy-mediated chemotherapy resistance in human cancer LoVo and HeLa cells in vitro. Treatment of human colon cancer LoVo cells with doxorubicin (0.5 µmol/L) induced autophagy activation and nuclear translocation of TFEB, which resulted from inactivation of the mTOR pathway. In both LoVo and HeLa cells, overexpression of TFEB enhanced doxorubicin-induced autophagy activation and significantly decreased doxorubicin-induced cell death, whereas knockdown of TFEB with small interfering RNA blocked doxorubicin-induced autophagy and significantly enhanced the cytotoxicity of doxorubicin. In LoVo cells, autophagy inhibition by 3-methyladenine (3-MA) or knockdown of autophagy-related gene Atg5 increased cell death in response to doxorubicin, and abolished TFEB overexpression-induced chemotherapy resistance, suggesting that the inhibition of autophagy made cancer cells more sensitive to doxorubicin. The results demonstrate that TFEB-mediated autophagy activation decreases the sensitivity of cancer cells to doxorubicin.

Oxymatrine synergistically enhances antitumor activity of oxaliplatin in colon carcinoma through PI3K/AKT/mTOR pathway.

Oxymatrine (OMT), one of the main active components of extracts from the dry roots of Sophora flavescens, has been reported to possess many pharmacological properties including cancer-preventive and anti-cancer effects. The aim of the present study is to explore the efficiency of combination therapy with OMT and oxaliplatin (OXA) and identify the in vitro and in vivo cytotoxicity on colon cancer lines (HT29 and SW480) and mice model. Cells were treated with OMT and/or OXA and subjected to cell viability, colony formation, apoptosis, cell cycle, western blotting, xenograft tumorigenicity assay and immunohistochemistry. The results demonstrated that OMT and OXA inhibited the proliferation of colon cancer cells, and combination therapy of OMT and OXA resulted in a combination index < 1, indicating a synergistic effect. Co-treatment with OMT and OXA caused G0/G1 phase arrest by upregulating P21, P27 and downregulating cyclin D, and induced apoptosis through decreasing the expression of p-PI3K, p-AKT, p-mTOR, p-p70S6K. In addition, pretreatment with a specific PI3K/AKT activator (IGF-1) significantly neutralized the pro-apoptotic activity of OXA + OMT, demonstrating the important role of PI3K/AKT in this process. Moreover, in nude mice model, co-treatment displayed more efficient inhibition of tumor weight and volume on SW480 xenograft mouse model than single-agent treatment with OXA or OMT. Immunohistochemistry analysis suggests the combinations greatly suppressed tumor proliferation, which consistent with our in vitro results. In conclusion, our findings highlight that the combination therapy with OMT and OXA exerted synergistic antitumor effects in colon cancer cells through PI3K/AKT/mTOR pathway and combination treatment with OMT and OXA would be a promising therapeutic strategy for colon carcinoma treatment.

Quercetin induces apoptosis and enhances 5-FU therapeutic efficacy in hepatocellular carcinoma.

Quercetin (Q), a flavonoid compound, which is obtained in variety of fruits, seeds, and vegetables, has been reported to possess many pharmacological properties including cancer-preventive and anticancer effects. However, studies on the anticancer effects and underlying mechanisms of Q in human hepatocellular carcinoma (HCC) are still limited. The present study is conducted to investigate the anticancer efficacy and adjuvant chemotherapy action of Q in HCC. HCC cell lines HepG2 and SMCC-7721 were treated with different concentrations of Q. The antiproliferative effects of Q were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), and the apoptosis and cell cycle dynamics were assessed by flow cytometry; the expression of apoptosis-associated proteins were evaluated by Western blot and immunohistochemistry staining; the tumor growth in vivo was evaluated in a xenograft mouse model. Our results showed that Q effectively inhibited human HCC cell proliferation and induced apoptosis by upregulating the expression of Bad and Bax and downregulating the expression of Bcl-2 and Survivin in vitro. Furthermore, Q obviously inhibited the tumor growth and enhanced the 5-fluorouracil (5-FU) therapeutic efficacy in vitro and in vivo. Taken together, our findings highlight that Q effectively inhibited the growth of tumor and enhanced the sensitivity to thermotherapy, indicating Q is a potential treatment option for HCC.

Oxymatrine synergistically enhances the inhibitory effect of 5-fluorouracil on hepatocellular carcinoma in vitro and in vivo.

Oxymatrine (OMT), one of the main active components of extracts from the dry roots of Sophora flavescens, has long been employed clinically to treat cancers. Here, we investigated the synergistic effect of OMT with 5-fluorouracil (5-Fu) on the tumor growth inhibition of hepatocellular carcinoma cells (HCC; Hep-G2 and SMMC-7721) and explored the underlying mechanism. Cells were treated with OMT and/or 5-Fu and subjected to cell viability, colony formation, apoptosis, cell cycle, western blotting, xenograft tumorigenicity assay, and immunohistochemistry. OMT and 5-Fu inhibited the proliferation of Hep-G2 and SMMC-7721 cells, and combination treatment with OMT and 5-Fu resulted in a combination index <1, indicating a synergistic effect. Co-treatment with OMT and 5-Fu caused G0/G1 phase arrest by upregulating P21 and P27 and downregulating cyclin D, and induced apoptosis through increasing the production of reactive oxygen species (ROS) and decreasing the levels of p-ERK. In addition, the inhibition of ROS respectively reversed the cell death induced by 5-Fu + OMT, suggesting the key roles of ROS in the process. More importantly, 5-Fu and OMT in combination exhibit much superior tumor weight and volume inhibition on SMMC-7721 xenograft mouse model in comparison to 5-Fu or OMT alone. Immunohistochemistry analysis suggests the combinations greatly suppressed tumor proliferation, which was consistent with our in vitro results. Taken together, our findings indicated that OMT sensitizes HCC to 5-Fu treatment by the suppression of ERK activation through the overproduction of ROS, and combination treatment with OMT and 5-Fu would be a promising therapeutic strategy for HCC treatment.

Anti-tumor activities of matrine and oxymatrine: literature review.

Matrine (MT) and oxymatrine (OMT), two kinds of alkaloid components found in the roots of Sophora species, have various pharmacological activities and are demonstrated to have anti-inflammatory, anti-allergic, anti-virus, anti-fibrotic, and cardiovascular protective effects. They are recently proved to have anti-cancer potentials, such as inhibiting cancer cell proliferation, inducing cell cycle arrest, accelerating apoptosis, restraining angiogenesis, inducing cell differentiation, inhibiting cancer metastasis and invasion, reversing multidrug resistance, and preventing or reducing chemotherapy- or radiotherapy-induced toxicity when combined with other chemotherapeutic drugs. In this review, we summarize the recent investigations regarding the anti-cancer activities and possible molecular targets of MT and OMT for cancer prevention and treatment in order to provide clues and references for further study.

The prognostic importance of jaundice in surgical resection with curative intent for gallbladder cancer.

BACKGROUND: Preoperative jaundice is frequent in gallbladder cancer (GBC) and indicates advanced disease. Resection is rarely recommended to treat advanced GBC. An aggressive surgical approach for advanced GBC remains lacking because of the association of this disease with serious postoperative complications and poor prognosis. This study aims to re-assess the prognostic value of jaundice for the morbidity, mortality, and survival of GBC patients who underwent surgical resection with curative intent. METHODS: GBC patients who underwent surgical resection with curative intent at a single institution between January 2003 and December 2012 were identified from a prospectively maintained database. RESULTS: A total of 192 patients underwent surgical resection with curative intent, of whom 47 had preoperative jaundice and 145 had none. Compared with the non-jaundiced patients, the jaundiced patients had significantly longer operative time (p < 0.001) and more intra-operative bleeding (p = 0.001), frequent combined resections of adjacent organs (23.4% vs. 2.8%, p = 0.001), and postoperative complications (12.4% vs. 34%, p = 0.001). Multivariate analysis showed that preoperative jaundice was the only independent predictor of postoperative complications. The jaundiced patients had lower survival rates than the non-jaundiced patients (p < 0.001). However, lymph node metastasis and gallbladder neck tumors were the only significant risk factors of poor prognosis. Non-curative resection was the only independent predictor of poor prognosis among the jaundiced patients. The survival rates of the jaundiced patients with preoperative biliary drainage (PBD) were similar to those of the jaundiced patients without PBD (p = 0.968). No significant differences in the rate of postoperative intra-abdominal abscesses were found between the jaundiced patients with and without PBD (n = 4, 21.1% vs. n = 5, 17.9%, p = 0.787). CONCLUSIONS: Preoperative jaundice indicates poor prognosis and high postoperative morbidity but is not a surgical contraindication. Gallbladder neck tumors significantly increase the surgical difficulty and reduce the opportunities for radical resection. Gallbladder neck tumors can independently predict poor outcome. PBD correlates with neither a low rate of postoperative intra-abdominal abscesses nor a high survival rate.

[Retracted] Aberrant expression of B7­H3 in gastric adenocarcinoma promotes cancer cell metastasis.

Following the publication of the above paper, an interested reader drew to the authors' attention that the scratch­wound assay data featured in Fig. 5A on p. 2090 appeared to contain some overlapping data comparing between the panels, such that these data, which were intended to show the results from differently performed experiments, may have been derived from the same original source. After having re­examined their original data, the authors conceded that the figure had been assembled incorrectly (specifically, four of the images selected out of the nine data panels included in this figure part had been chosen erroneously). Furthermore, the first author on the paper (Wei Dai) also acknowledged that several of the named authors had not given their prior consent to be included as such as authors on the paper, and therefore a request was made that the paper be retracted from the publication. In view of these admissions, the Editor of Oncology Reports has accepted the authors' request that the paper be retracted from the journal. The Editor apologizes to the readership for any inconvenience caused. [Oncology Reports 32: 2086­2092, 2014; DOI: 10.3892/or.2014.3405].

Retraction Note to: Lupeol induces apoptosis and inhibits invasion in gallbladder carcinoma GBC-SD cells by suppression of EGFR/MMP-9 signaling pathway.

[This retracts the article DOI: 10.1007/s10616-014-9763-7.].

Retraction: Oxymatrine Synergistically Potentiates the Antitumor Effects of Cisplatin in Human Gastric Cancer Cells.

[This retracts the article DOI: 10.7150/jca.28532.].

Anti-tumor Activity of Bufalin by Inhibiting c-MET Mediated MEK/ERK and PI3K/AKT Signaling Pathways in Gallbladder Cancer.

Gallbladder cancer is one of the most common malignant tumors in the biliary tract. In recent years, the chemotherapy treatment for gallbladder carcinoma has exhibited obvious characteristics of drug resistance and insensitivity, and one of the main factors is the existence of cancer stem cells. Here in this study, the effect of Bufalin on gallbladder cancer (GBC-SD) cells and the related mechanism were studied. The results indicated that Bufalin could inhibit the growth of gallbladder carcinoma both in vivo and in vitro. According to the biological behavior analysis, Bufalin induced apoptosis, inhibited the propagation, migration and invasion of GBC-SD cells, and blocked cell cycle at the G2/M stage. Besides, Bufalin inhibited the tumor sphere formation capability of gallbladder carcinoma in matrigel, reduced the expression of multiple stemness-associated proteins, including Oct4, Sox2 and the stem cell-surface marker proteins CD133 and CD44. Western blot assay showed that Bufalin inhibited MEK/ERK and PI3-K/AKT signaling pathways by inhibiting the expression of p-c-Met, which in turn affected the expression of apoptosis-related protein Mcl-1, and the invasion-associated proteins E-cadherin, MMP9 and Snail. Bufalin was found to have an inhibitory effect on the GBC-SD cell growth and reduce the self-renewal and characteristic of gallbladder cancer stem cells. It enhanced the chemotherapeutic sensitivity and reduced the metastasis of gallbladder carcinoma. In conclusion, Bufalin can be used as a new promising anticancer drug for gallbladder cancer patients who are resistant to traditional chemotherapy.

S-Adenosylmethionine synergistically enhances the antitumor effect of gemcitabine against pancreatic cancer through JAK2/STAT3 pathway.

Gemcitabine (GEM) has been widely used for pancreatic cancer (PC) treatment but limited by the development of drug resistance. The agents that reverse its resistance and improve the chemo-sensitivity are urgently needed. S-Adenosylmethionine (SAM) is a precursor for polyamine biosynthesis in mammalian cells and plays a key role in biological transmethylation events. It is reported that SAM could be used as a therapeutic reagent for cancer treatments. In this study, we investigated the chemo-sensitization of SAM to potentiate the antitumor effect of GEM in PC. After treating PC cells with GEM and/or SAM, different subsequent experiments were performed. Results showed that SAM plus GEM could significantly inhibit the growth and proliferation of PC cells, and SAM acts synergistically with GEM. The combinative treatment could induce cell apoptosis and inhibit invasion and migration through JAK2/STAT3 inactivation. Inhibition of JAK2/STAT3 pathway significantly enhanced the pro-apoptotic effect of SAM, suggesting the key roles of JAK2/STAT3 in the process. Moreover, co-treatment with GEM and SAM exhibited more efficient inhibition of tumor weight and volume on PANC-1 xenograft mouse model compared to GEM or SAM alone and has no significant effect on the function of the liver and kidney. In general, this study indicated that SAM synergistically enhanced the antitumor effect of GEM against PC through suppressed JAK2/STAT3 pathway, and SAM is applicable as a promising agent to improve the sensitivity of PC to GEM.

Oct4 promotes cancer cell proliferation and migration and leads to poor prognosis associated with the survivin/STAT3 pathway in hepatocellular carcinoma.

Octamer­binding transcription factor 4 (Oct4) has been identified as a novel transcription factor associated with tumorigenesis, acquisition and maintenance of cancer stem cell characteristics and poor prognosis in tumors. However, the role of Oct4 in tumorigenesis and progression of hepatocellular carcinoma (HCC) has not yet been fully elucidated. In our present study, we observed that the Oct4 expression level was upregulated in HCC specimens as well as in different HCC cell lines. In in vitro experiments, decreased expression of Oct4 by shRNA inhibited the viability and mobility of HCC cells. Furthermore, the loss of Oct4 inhibited HCC cell malignant progression accompanied by downregulated expression of the survivin/signal transducer and activator of transcription 3 (STAT3) pathway. Liver cancer patients with high expression of Oct4 exhibited significantly shorter overall and disease­free survival. These findings demonstrated that Oct4 plays a vital role in the malignant progression of HCC cells through the survivin/STAT3 signaling pathway, and it may prove to be a novel biomarker associated with patient prognosis and survival.

Oxymatrine Synergistically Potentiates the Antitumor Effects of Cisplatin in Human Gastric Cancer Cells.

Cisplatin (CDDP) has been extensively used for gastric cancer (GC) treatment but limited by drug resistance and severe toxicity. The chemo-sensitizers that enhance its efficiency and overcome its limitation are urgently needed. Oxymatrine (OMT), a primary active ingredient from the dry roots of Sophora favescens, has shown powerful anti-cancer property with little side-effect. In this study, we explored the chemo-sensitization of OMT to potentiate the anti-tumor effect of CDDP. GC cell lines were dealt with OMT and/or CDDP and then subjected to different experimental methods. We found that OMT could significantly potentiate the CDDP-caused BGC-823 and SGC7901 cells viability loss, and OMT acts synergistically with CDDP. The combinative treatment could arrest cell cycle in G0/G1 phase by increasing p21, p27 and decreasing cyclin D1, and induced apoptosis by ROS generation and AKT/ERK inactivation. Inhibition of ROS respectively reversed the cell death induced by OMT and/or CDDP, suggesting the pivotal roles of ROS in the process. Moreover, OMT enhanced the antitumor effects of CDDP in nude mice bearing BGC823 tumor xenografts in vivo. Taken together, this study highlights that the co-treatment with OMT and CDDP exerted synergistic antitumor effects in GC cells, and that these effects may be mediated by ROS generation and inactivation of the AKT/ERK pathways.

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.

Downregulation of MACC1 inhibits the viability, invasion and migration and induces apoptosis in esophageal carcinoma cells through the phosphatase and tensin homolog/phosphoinositide 3-kinase/protein kinase B signaling pathway.

As an oncogene, MACC1 serves an important function in cancer progression and metastasis. However, the effect of MACC1 in esophageal carcinoma (EC) remains to be fully understood. The present study assessed the association between MACC1 expression and the progression of EC cells. A small interfering (si)RNA was delivered into EC cells to downregulate MACC1 expression. The MTT assay demonstrated that EC cell viability was reduced by siRNA-MACC1. Decreasing MACC1 expression increased the apoptotic rate of EC cells compared with control cells. Transwell and Matrigel assays demonstrated that EC cell migration and invasion, respectively, were downregulated by siRNA-MACC1. Furthermore, knocking down MACC1 suppressed the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway by upregulating the expression of phosphatase and tensin homolog (PTEN), a tumor suppressor. The results of the present study revealed that MACC1 expression affected cellular functions of the EC cells through the PTEN/PI3K/Akt signaling pathway. Therefore, MACC1 may potentially serve as a novel biomarker and therapeutic target for EC.

Mirizzi syndrome with an unusual aberrant hepatic duct fistula: a case report.

Mirizzi syndrome (MS) is a rare complication of chronic cholelithiasis, which is always caused by a calculus in the cystic duct or neck of the gallbladder, resulting in mechanical compression of common bile duct and the gallbladder. It is clinically characterized by abdominal pain, fever, as well as obstructive jaundice. During cholecystectomy, MS is seen as a dangerous adherent and inflammatory tissue in the area of Calot's triangle. In the general population, aberrant right posterior hepatic duct, one of the causes of bile duct injury during duct surgery, is present in 4.8%-8.4% of people. Herein we report a rare case of a 76-year-old female patient, with hepatolithiasis of right posterior lobe and cholecysto-aberrant right posterior hepatic duct fistula. This is a special type of MS; however, interestingly, she did not have any symptoms, and the disease was found by physical examination incidentally. This case highlights another situation, namely, there may be difficulty in diagnosing MS and dissecting for operation. Therefore, to avoid the complication associated with this special situation, the surgeons need to diagnose carefully and adopt an optimal treatment strategy.