Ganlu Deng

Chemotherapy and target therapy for hepatocellular carcinoma: New advances and challenges

Primary liver cancer is one of the commonest causes of death. Hepatocellular carcinoma (HCC) accounts for 90% of primary liver cancers. For patients with unresectable or metastatic HCC, conventional chemotherapy is of limited or no benefit. Sorafenib is the only systemic treatment to demonstrate a statistically significant but modest overall survival benefit, leading to an era of targeted agents. Many clinical trials of targeted drugs have been carried out with many more in progress. Some drugs like PTK787 showed potential benefits in the treatment of HCC. Despite these promising breakthroughs, patients with HCC still have a dismal prognosis. Recently, both a phase III trial of everolimus and a phase II clinical trial of trebananib failed to demonstrate effective antitumor activity in advanced HCC. Sorafenib still plays a pivotal role in advanced HCC, leading to further explorations to exert its maximum efficacy. Combinations targeted with chemotherapy or transarterial chemoembolization is now being tested and might bring about advances. New targeted agents such as mammalian target of rapamycin inhibitors are under investigation, as well as further exploration of the mechanism of hepatocarcinogenesis.

A prognostic analysis of 895 cases of stage III colon cancer in different colon subsites

PurposeStage III colon cancer is currently treated as an entity with a unified therapeutic principle. The aim of the retrospective study is to explore the clinicopathological characteristics and outcomes of site-specific stage III colon cancers and the influences of tumor location on prognosis.MethodsEight hundred ninety-five patients with stage III colon cancer treated with radical operation and subsequent adjuvant chemotherapy (5-fluorouracil/oxaliplatin) were divided into seven groups according to colon segment (cecum, ascending colon, hepatic flexure, transverse colon, splenic flexure, descending colon, and sigmoid colon). Expression of excision repair cross-complementing group 1 (ERCC1) and thymidylate synthase (TS) was examined by immunohistochemistry. We assessed if differences exist in patient characteristics and clinic outcomes between the seven groups.ResultsThere were significant differences in tumor differentiation (P < 0.001), T stage (P < 0.001), N stage (P < 0.001), American Joint Committee on Cancer (AJCC) tumor–node–metastasis (TNM) stage (P < 0.001), metachronous liver metastasis (P < 0.001), metachronous lung metastasis (P < 0.001), and ERCCI expression (P < 0.001) between the seven groups. Both 5-year recurrence-free survival (RFS) and 5-year overall survival (OS) exhibited significant differences (both P < 0.001) with survival gradually decreasing from cecum to sigmoid colon. Cox regression analyses identified that tumor location was an independent prognostic factor for RFS and OS.ConclusionsStage III colon cancer located proximally carried a poorer survival than that located distally. Different efficacies of FOLFOX adjuvant chemotherapy may be an important factor affecting survival of site-specific stage III colon cancers.

Nestin overexpression in hepatocellular carcinoma associates with epithelial-mesenchymal transition and chemoresistance

BackgroundNestin expression has been reported to be associated with the prognosis of many solid tumors including human hepatocellular carcinoma (HCC). The present study aimed to identify the role, if any, of Nestin in the chemotherapeutic treatment of HCC.MethodsWe determined Nestin expression in nine HCC cell lines and 220 tissue samples of advanced HCC patients (retrospectively registered) treated with FOLFOX regimens. We examined the correlations between Nestin expression and clinicopatholgical variables and HCC prognosis. Also, we used in vitro and in vivo methods to determine the effects of Nestin expression on HCC cell invasion, migration and chemosensitivity.ResultsNestin expression was significantly increased in HCC tissues and drug-resistant cell lines, and the presence of high levels of Nestin was associated with poor survival. We also showed that drug-resistance occurred in HCC cells with epithelial-mesenchymal transition (EMT), which in turn enhanced invasion ability. Nestin depletion reversed drug-resistance in the Bel-7402/5-FU and Bel-7402/ADM cell lines. Nestin knockdown enhanced chemotherapeutic efficacy in nude mice. Moreover, Nestin up-regulation in Bel-7402 was associated with the activation of Wnt/β-catenin signaling.ConclusionOur findings suggest that Nestin inhibitors may be useful for the chemotherapy of HCC.

The anti-tumor activities of Neferine on cell invasion and oxaliplatin sensitivity regulated by EMT via Snail signaling in hepatocellular carcinoma

Tumor invasion and chemotherapy resistance, which are associated with epithelial-mesenchymal transition (EMT), remain as major challenges in hepatocellular carcinoma (HCC) treatment. Neferine, a natural component of Nelumbo nucifera, have been proven the antitumor efficiency in cancer, but the effects of Neferine on HCC invasion and chemosensitivity need to be elucidated. Applying multiple assays of cell proliferation, flow cytometry, immunofluorescence staining, qRT-PCR, Western blot, fluorescence molecular tomography imaging, the influences of Neferine on EMT-regulated viability, apoptosis, invasion, and oxaliplatin (OXA) sensitivity were assessed in HCC cells of HepG2 and Bel-7402, as well as in xenograft animal models in vivo. Here, we reported that Neferine had no obvious effects on HCC cells proliferation, but significantly enhanced cytotoxicity and apoptosis caused by OXA in vitro and in vivo. Through an upregulation of E-cadherin and downregulation of Vimentin, Snail and N-cadherin, Neferine suppressed EMT-induced migration and invasion abilities of HCC cells. TGF-β1 cancelled the effects of Neferine on the migration and invasion of HCC cells. Snail overexpression or TGF-β1-induced EMT attenuated Neferine-mediated OXA sensitization in HCC. Together, our data suggest that Neferine enhances oxaliplatin sensitivity through an inhibition of EMT in HCC cells. Neferine may be used as an OXA sensitizer in HCC chemotherapy.

Integrin-linked kinase overexpression promotes epithelial-mesenchymal transition via nuclear factor-κB signaling in colorectal cancer cells

AIM To investigate the effect of integrin-linked kinase (ILK) on proliferation, metastasis, and invasion of the colorectal cancer cell line SW480. METHODS In this study, the colorectal cancer cell line SW480 was stably transfected with ILK plasmids, and small interfering RNA (siRNA) was used to knockdown expression of nuclear factor (NF)-κB/p65. Methylthiazole tetrazolium (MTT) assay was performed to measure proliferation, and the wound healing migration assay and matrigel invasion assay were used to test the metastasis and invasion ability of SW480 cells. To explore the epithelial-mesenchymal transition (EMT) process, embryonic development, and the invasion and metastasis of tumors, the protein level of E-cadherin, vimentin, snail, and slug was detected by western blot. Immunofluorescence was also used to detect E-cadherin expression. Western blot was used to determine the level of phosphorylated-inhibitor of kappa B (IκB)a, inhibitor of gamma B (IγB)a, and nuclear factor kappa B (NF-κB) expressions and to explore the ILK signaling pathway. RESULTS Western blot results revealed that ILK expression significantly increased when ILK was overexpressed in SW480 cells (P < 0.05). Proliferation, metastasis, and invasion ability were improved in the vector-ILK group compared to the vector group (P < 0.05). Immunofluorescence results revealed that E-cadherin fluorescence intensity decreased after ILK was overexpressed (P < 0.05). Western blot results revealed that the protein expression of E-cadherin was reduced, while vimentin, snail, and slug were upregulated when ILK was overexpressed in SW480 cells (P < 0.05). In order to determine the role of the NF-κB signaling pathway in ILK overexpression promoted EMT occurrence, we overexpressed ILK in SW480 cells and found that levels of NF-κB/p65 and cytoplasmic phosphorylated-IκBa were increased and that cytoplasmic IкBa levels were decreased compared to the control group (P < 0.05). Furthermore, NF-κB/p65 knockout revealed that E-cadherin was increased in the overexpressed ILK group. CONCLUSION ILK overexpression improved the proliferation, metastasis, and invasion ability of SW480 cells, and this effect may be mediated by the NF-κB signaling pathway.

ZEB1 Promotes Oxaliplatin Resistance through the Induction of Epithelial - Mesenchymal Transition in Colon Cancer Cells

Background: Oxaliplatin (OXA) chemotherapy is widely used in the clinical treatment of colon cancer. However, chemo-resistance is still a barrier to effective chemotherapy in cases of colon cancer. Accumulated evidence suggests that the epithelial mesenchymal transition (EMT) may be a critical factor in chemo-sensitivity. The present study investigated the effects of Zinc finger E-box binding homeobox 1 (ZEB1) on OXA-sensitivity in colon cancer cells. Method: ZEB1expression and its correlation with clinicopathological characteristics were analyzed using tumor tissue from an independent cohort consisting of 118 colon cancer (CC) patients who receiving OXA-based chemotherapy. ZEB1 modulation of OXA-sensitivity in colon cancer cells was investigated in a OXA-resistant subline of HCT116/OXA cells and the parental colon cancer cell line: HCT116. A CCK8 assay was carried out to determine OXA-sensitivity. qRT-PCR, Western blot, Scratch wound healing and transwell assays were used to determine EMT phenotype of colon cells. ZEB1 knockdown using small interfering RNA (siRNA) was used to determine the ZEB1 contribution to OXA-sensitivity in vitro and in vivo (in a nude mice xenograft model). Result: ZEB1 expression was significantly increased in colon tumor tissue, and was correlated with lymph node metastasis and the depth of invasion. Compared with the parental colon cancer cells (HCT116), HCT116/OXA cells exhibited an EMT phenotype characterized by up-regulated expression of ZEB1, Vimentin, MMP2 and MMP9, but down-regulated expression of E-cadherin. Transfection of Si-ZEB1 into HCT116/OXA cells significantly reversed the EMT phenotype and enhanced OXA-sensitivity in vitro and in vivo. Conclusion: HCT116/OXA cells acquired an EMT phenotype. ZEB1 knockdown effectively restored OXA-sensitivity by reversing EMT. ZEB1 is a potential therapeutic target for the prevention of OXA-resistance in colon cancer.

BMP4 enhances hepatocellular carcinoma proliferation by promoting cell cycle progression via ID2/CDKN1B signaling

Bone morphogenetic protein‐4 (BMP4) plays a crucial role in carcinogenesis, but the effects and signaling mechanisms of BMP4 in hepatocellular carcinoma (HCC) are not clearly clarified. The present study aimed to identify the roles of BMP4 in the proliferation of human HCC. In this study, BMP4 expression and its correlation with clinicopathological characteristics and the survival of HCC patients were analyzed in two independent cohorts consisting of 310 subjects. Functional analysis of BMP4 on HCC proliferation was performed in vitro and in vivo in human HCC specimens, HCC cells of Bel‐7402 and HCCLM3, and subcutaneous tumor model. The downstream signaling targets of BMP4 in HCC were investigated by PCR Array and Western blot. The results indicated that BMP4 expression was significantly increased in HCC tissues and closely related with unfavorable prognosis of HCC. BMP4 treatment increased cell proliferation and promoted G1/S cell cycle progression. In vivo subcutaneous tumor of nude mice model supported that BMP4 overexpression promoted the growth of HCC cells and BMP4 knockdown hold the opposite trend. Id2 was directly upregulated by BMP4, resulting in the mediated expression of cell cycle regulatory protein of CDKN1B. Blocking of Id2 attenuated BMP4‐induced proliferation, confirming the important roles of Id2 in BMP4‐mediated proliferation in HCC. So BMP4 is overexpressed in HCC tissues and acts as a poor prognostic factor of HCC patients. BMP4‐induced ID2/CDKN1B signaling facilitates proliferation of HCC.

Knockdown of Beclin-1 impairs epithelial-mesenchymal transition of colon cancer cells

Activation of autophagy significantly affects cancer cell behaviors, such as proliferation, differentiation, and invasiveness. Epithelial‐to‐mesenchymal transition (EMT) as an initial step of malignant transformation of cancer cells was linked to the activation of autophagy, but the detailed molecular mechanisms are still unknown. The present study investigates the effects of Beclin‐1, a key molecule involved in activation of autophagy, on EMT of colon cancer cells. The normal colon epithelia cell line of CCD‐18Co and six colon cancer cell lines with different expression levels of Beclin‐1 were used in this study. The activation of autophagy and EMT markers of cancer cells were monitored by Western blotting and quantitative real‐time PCR assay in the presence or absence of rapamycin (autophagy activator) and 3‐MA (autophagy inhibitor). The expression of Beclin‐1 in selected cell lines was modulated using small interfering RNA, and consequentially EMT markers, and cancer cell behaviors including migration and invasion, were also explored. Activation or inhibition of autophagy in colon cancer cells had positive or negative impacts on the expression of EMT markers and malignant behaviors such as cell migration and invasion. Knockdown of beclin‐1 by siRNA apparently inhibited the activation of autophagy induced by rapamycin, consequentially resulted in suppression of EMT and attenuation of invasiveness of colon cancer cells. The results in this study demonstrated an association between activation of autophagy and EMT in colon cancer cells. The results showed suppression of Beclin‐1 expression significantly reduced EMT and invasive behaviors in colon cancer cells.

BMP4 promotes hepatocellular carcinoma proliferation by autophagy activation through JNK1-mediated Bcl-2 phosphorylation

BackgroundAutophagy is a conserved catabolic process with complicated roles in tumor development. Bone morphogenetic protein 4 (BMP4), a member of the transforming growth factor (TGF-β) family of regulatory proteins, plays a crucial role in human malignancies. However, whether BMP4 contributes to the regulation of autophagy in hepatocellular carcinoma (HCC) progression remains elusive.MethodsFunctional analysis of BMP4 on HCC proliferation and autophagy was performed both in vitro and in vivo in HepG2 and HCCLM3 cells. Autophagic activity was estimated by Western blot for autophagic marker proteins and by transmission electron microscopy (TEM). Transfection of mRFP-GFP-LC3 adenovirus was applied to observe autophagic flux and high content screening was used for quantification. The signaling pathway of BMP4-regulated HCC proliferation and autophagy was investigated by Western blot.ResultsBMP4 treatment promoted HCC cells proliferation and induced autophagy. The in vivo xenograft model supported that BMP4 overexpression promoted the growth of HCC cells and autophagy induction while BMP4 knockdown exerted the opposite effect. 3-MA pre-treatment or knockdown of Beclin-1 (BECN1) blocked HCC autophagy by decreasing the expression of LC3-II and subsequently attenuated BMP4-induced autophagy and cells proliferation enhanced by BMP4 in vitro and in vivo. Mechanistic study revealed that the induction of autophagy by BMP4 was mediated through activating the JNK1/Bcl2 pathway. Furthermore, the JNK1 inhibitor and knockdown of JNK1 could attenuate autophagy induced by BMP4 and eliminated BMP4-promoted HCC cells growth.ConclusionsBMP4 promoted HCC proliferation by autophagy activation through JNK1/Bcl-2 signaling.