Doxorubicin In Hepatocellular Carcinoma Research Articles

Efficacy of CalliSpheres® drug-loaded microspheres combined with doxorubicin in hepatocellular carcinoma.

This study compared the efficacy and safety of the transarterial chemoembolization with CalliSpheres® drug-eluting beads loading with doxorubicin (DEB-TACE) versus conventional lipiodol (cTACE) in patients with unresectable hepatocellular carcinoma (HCC). A randomized controlled trial (RCT) was conducted with 144 patients, who were randomly assigned to receive either DEB-TACE with doxorubicin-loaded CalliSpheres® microspheres or cTACE with doxorubicin-lipiodol emulsion. Patients were followed up for 12 months, with assessments at 3 and 12 months posttreatment. The primary endpoint was the clinical response rate (CR), and the secondary endpoints were the overall survival (OS), the progression-free survival (PFS), and the safety profile of the two treatments. The results showed that DEB-TACE was superior to cTACE in terms of CR (50.0% vs 30.6% at 3 months, p = 0.03; 43.1% vs 25.0% at 12 months, p = 0.04), OS (18.2 months vs 14.6 months, p < 0.05), and PFS (7.4 months vs 4.8 months, p < 0.05), and that the safety profile of the two treatments was similar (p > 0.05 for all comparisons). However, the efficacy of DEB-TACE and cTACE varied according to the tumor morphology. DEB-TACE showed better CR rates in patients with nodular tumors, while no significant difference in CR between the two groups in patients with infiltrative tumors. DEB-TACE showed superior efficacy to cTACE in terms of CR, OS, and PFS, particularly in patients with nodular tumors, while maintaining a similar safety profile. These findings suggest that tumor morphology could inform treatment decisions for TACE in HCC patients.

Targeting the YAP/TAZ mechanotransducers in solid tumour therapeutics.

Targeting the YAP/TAZ mechanotransducers in solid tumour therapeutics.

Blocking the CXCL1-CXCR2 axis enhances the effects of doxorubicin in HCC by remodelling the tumour microenvironment via the NF-κB/IL-1β/CXCL1 signalling pathway

Inflammation is a core mechanism for oncogenesis. Chemokines act as important mediators of chronic inflammation and the tumour inflammatory response. However, there is limited information on chemokines in hepatocellular carcinoma (HCC), a disease for which almost all cases are derived from chronic liver inflammation. Here, we explored the protumor effects of CXCL1, a commonly elevated inflammatory chemokine in cirrhosis, in HCC. The protumor role was confirmed in clinical samples from HCC patients. CXCL1 enhanced tumorigenesis in the hepatic inflammatory microenvironment directly by acting on tumour cells and indirectly through promoting the recruitment of macrophages. The increase in the number of macrophages in the tumour microenvironment (TME) promoted tumour cell epithelial-mesenchymal transition (EMT) and significantly increased CXCL1 levels in the TME partly through NF-κB/IL-1β activation. To investigate the potential therapeutic value of CXCL1 in HCC with an inflammatory background, an antibody blocking CXCL1 was used alone or combined with the chemotherapy agent doxorubicin (DOX), with the goal of reshaping the TME. It has been shown that blocking CXCL1-CXCR2 inhibits tumour progression and reduces macrophage recruitment in the TME. The combination regimen has been shown to synergistically reduce the number of pro-tumour macrophages in the TME and suppress tumour progression. This provides insight into therapeutic strategies for treating HCC patients with high CXCL1 expression.

A multi-strategy liposome targeting hepatocellular carcinoma cells and stem cells enhances the chemotherapy effect of doxorubicin in hepatocellular carcinoma

A multi-strategy liposome targeting hepatocellular carcinoma cells and stem cells enhances the chemotherapy effect of doxorubicin in hepatocellular carcinoma

Isoginkgetin synergizes with doxorubicin for robust co-delivery to induce autophagic cell death in hepatocellular carcinoma

Doxorubicin (DOX) widely used in hepatocellular carcinoma (HCC) can induce serious side effects and drug resistance. Herein, we aimed to seek a strategy to improve the efficacy and reduce the side effects of DOX in HCC based on an autophagy inducer drug called isoginkgetin (ISO). The design of multifunctional nanocarriers based on hyaluronic acid-conjugated and manganese-doped mesoporous silica nanoparticles (HM) for the co-delivery of antitumor drugs against HCC provided an effective and promising antitumor strategy. Our results showed that HM@ISO@DOX could efficiently inhibit HCC cell proliferation through activating autophagy through AMPKa-ULK1 pathway. Moreover, intravenous injection of HM@ISO@DOX significantly suppressed HCC tumor progression in nude mouse HCC model. Collectively, our findings revealed an anti-HCC mechanism of HM@ISO@DOX through autophagy and provide an effective therapeutic strategy for HCC. Statement of significanceIn our study, we constructed a co-delivery system by loading ISO and DOX in the mesoporous channels of manganese-doped mesoporous silica nanoparticles, which could be further conjugated with hyaluronic acid to obtain HM@ISO@DOX. The nanocarriers had been demonstrated to be biodegradable under the acidic and reducing tumor microenvironment, as well as to possess the tumor targeting capability via the conjugated hyaluronic acid. In addition, HM@ISO@DOX enhanced the therapeutic efficacy against human HCC tumor through the combinatorial therapies of chemotherapeutics, Mn2+-mediated chemodynamic therapeutics and autophagic cell death, which might be achieved through AMPK-ULK1 signaling. This work revealed that such a nanomedicine exhibited superior tumor accumulation and antitumor efficiency against HCC with extremely low systemic toxicity in an autophagy-boosted manner.

FRI558 - Inhibiting IRE1a-endonuclease activity potentiates the effect of doxorubicin in hepatocellular carcinoma

FRI558 - Inhibiting IRE1a-endonuclease activity potentiates the effect of doxorubicin in hepatocellular carcinoma

The PGC1α/NRF1-MPC1 axis suppresses tumor progression and enhances the sensitivity to sorafenib/doxorubicin treatment in hepatocellular carcinoma

Targeting energy metabolism holds the potential to effectively treat a variety of malignant diseases, and peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC1α) is a key regulator of energy metabolism. However, PGC1α′s role in cancer, especially in hepatocellular carcinoma (HCC) remains largely unknown. In the present study, we reported that PGC1α was significantly downregulated in HCC cell lines and specimens. Moreover, reduced expression of PGC1α in tumor cells was correlated with poor prognosis. PGC1α overexpression substantially inhibited cell proliferation and induced apoptosis in vitro and in vivo. On the contrary, the knockdown of PGC1α produced the opposite effect. The mechanism was at least partially due to the upregulation of mitochondrial pyruvate carrier 1 (MPC1) caused by PGC1α, which promoted mitochondrial biogenesis by binding to nuclear respiratory factor 1 (NRF1). Consequently, the production of cellular reactive oxygen species (ROS) caused by mitochondrial oxidation was elevated above a critical threshold for survival. Furthermore, we found that PGC1α could enhance the antitumor activity of sorafenib and doxorubicin in HCC through ROS accumulation-mediated cell death. These results indicate that PGC1α/NRF1-MPC1 axis is involved in HCC progression and could be a promising target for HCC treatment.

ACUTE LUNG INJURY FOLLOWING TRANSCATHETER ARTERIAL CHEMOEMBOLIZATION WITH DRUG ELUTING BEADS LOADED WITH DOXORUBICIN

SESSION TITLE: Medical Student/Resident Diffuse Lung Disease SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Transcatheter arterial chemoembolization (TACE) is commonly used as palliative management of primary hepatocellular carcinoma (HCC). Acute lung injury after this procedure is very rarely reported but has been seen. We describe a case of TACE-induced pneumonitis. CASE PRESENTATION: A 60-year old female with significant past medical history of hepatocellular carcinoma, hepatitis C cirrhosis complicated by ascites, bleeding varices, and encephalopathy presented for scheduled transcatheter arterial chemoembolization (TACE). She received TACE of LC beads loaded with doxorubicin of the left hepatic artery. She had this procedure three times prior in the past year without any complications. On hospital day 3 she was noted to have an episode of desaturation to the mid-70s, chest x-ray was done and showed no acute pathology. She continued to require 1-2L of oxygen via nasal cannula and desaturation with ambulation. Pulmonary computed tomography angiography (CTA) was ordered due to continued oxygen requirement which showed new bilateral central ground-glass and reticular opacities with relative sparing of the lung bases, new since a CT chest performed 2 months prior. The patient had no infectious symptoms or leukocytosis, and remained hypoxemic despite aggressive diuresis- a workup for diffuse parenchymal lung disease included ANA, ANCA, CCP, RF, and hypersensitivity pneumonitis which were all negative. Bronchoscopic evaluation of the patient was considered, however she declined. She was started on prednisone for presumed TACE-induced pneumonitis and was discharged with home oxygen and follow-up with pulmonology. She was seen one month after discharge with repeat chest imaging which showed near complete resolution of the diffuse ground-glass opacities. She was no longer requiring supplemental oxygen at home and was started on a gradual steroid taper with plans to continue until subsequent follow-up in three months, however the patient passed away from complications of cirrhosis. DISCUSSION: TACE is commonly used as palliative treatment in primary HCC. The procedure involves occluding portions of the hepatic artery that supplies the tumor. Commonly reported complications of this procedure include postembolization syndrome which is characterized by fatigue and abdominal pain, other local complications such as ischemic necrosis which could result in liver failure, spontaneous rupture of tumor, and gallbladder infarction can occur. We described a case of acute lung injury three days after TACE with doxorubicin-eluting beads (DEB-TACE). Review of the literature revealed only a few case reports of such a complication. CONCLUSIONS: Although an unusual complication, this entity will be more important given the increasing prevalence of DEB-TACE. Reference #1: Aladdin, M. & Ilyas, M. (2011). Chemoembolization of Hepatocellular Carcinoma with Drug-Eluting Beads Complicated by Interstitial Pneumonitis. Seminars in Interventional Radiology, 28(2), 218-211. Reference #2: Alifakioti D. et al. (2014). Acute Eosinophilic and Neutrophilic Pneumonia Following Transarterial Chemoembolization with Drug-Eluting Beads loaded with Doxorubicin for Hepatocellular Carcinoma: A Case Report. Respiration 88, 426-429. Reference #3: Fang, LJ. et al. (2019). Clinical Characteristics and Outcomes of Acute Lung Injury Caused by Transcatheter Arterial Chemoembolization for Hepatocellular Carcinoma: A retrospectiveCohort Study from a Single Institution in China. Anal Cell Pathol. DISCLOSURES: No relevant relationships by Luan Nghiem, source=Web Response No relevant relationships by Sheshadrie Saha, source=Web Response no disclosure on file for Ryan Webster

Ginger Extract Loaded into Chitosan Nanoparticles Enhances Cytotoxicity and Reduces Cardiotoxicity of Doxorubicin in Hepatocellular Carcinoma in Mice

This study aimed to investigate the impact of ginger extract (GE) loaded into chitosan nanoparticles (CNPs) in enhancing cytotoxicity and reducing cardiotoxicity of doxorubicin (DXN) in hepatocellular carcinoma (HCC) induced mice. DXN and GE were loaded into CNPs and cytotoxicity of loaded and unloaded drugs against HepG2 cells was evaluated. HCC was induced in male albino mice by injection of diethylnitrosamine (DINA). Mice were divided into eight groups (n = 15): (1) normal control, (2) DINA, (3) CNPs, (4) free DXN, (5) CNPs DXN, (6) free GE, (7) CNPs GE, and (8) CNPs DXN + CNPs GE. Both GE and DXN loaded into CNPs showed a greater decline in cell viability of HepG2 cells than the unloaded forms. GE CNPs displayed pronounced anticancer activity In Vivo through apoptosis, greater down-regulation of multidrug resistance 1, enhancement of anti-oxidant activity and depletion of vascular endothelial growth factor content in liver tissues. GE CNPs in combination with DXN CNPs showed nearly normal hepatic lobule architecture and the greatest increase in apoptotic cell count. Co-treatment group had decreased cardiac malondialdehyde, tumor necrosis factor-α and serum activity of creatine kinase and lactate dehydrogenase. Combination of GE CNPs and DXN CNPs might be a potentially effective therapeutic approach for HCC.

MicroRNA200a enhances antitumor effects in combination with doxorubicin in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is often treated with doxorubicin. MicroRNAs have been shown to have important regulatory roles in cancer and serve as a target in chemoresistance. In this study, we investigated the effects of specific microRNA-200a (miR-200a) on HCC tumor cell growth and effect of doxorubicin-mediated cytotoxicity. Our results show miR-200a is downregulated in human HCC and HCC tumor cell lines. Increasing miR-200a expression inhibited HCC growth and synergized with the antitumor effects of doxorubicin. Inhibiting endogenous miR-200a promoted tumor growth and chemotherapeutic resistance. Increasing miR-200a expression inhibited tumor metabolism (ATP production, mitochondrial respiration, glycolysis), while inhibition of endogenous miR-200a reversed these effects. MiR-200a expression also increased autophagy and synergized with doxorubicin-mediated cytotoxicity. This study identifies a novel role of miR-200a in potentiating doxorubicin-mediated therapeutic effects in HCC.

MicroRNA200a Enhances Antitumor Effects in Combination with Doxorubicin in Hepatocellular Carcinoma

MicroRNA200a Enhances Antitumor Effects in Combination with Doxorubicin in Hepatocellular Carcinoma

Endoplasmic Reticulum Stress-Induced Resistance to Doxorubicin Is Reversed by Mulberry Leaf Polyphenol Extract in Hepatocellular Carcinoma through Inhibition of COX-2.

Mulberry (Morus alba L.) leaves are used in Chinese medicine to treat metabolic disorders. Mulberry leaf polyphenol extracts (MLPE) have recently been shown to exhibit anticancer properties. Endoplasmic reticulum (ER) stress represents a pivotal obstacle in solid tumors, resulting in the antiapoptosis of tumor cells and drug resistance. In this study, pretreatment with the ER stress inducer tunicamycin (TM) attenuated the percentage of apoptosis induced by doxorubicin (DOX). Cotreatment with tunicamycin and MLPE reversed apoptosis induced by DOX. Simultaneously, induction of ER stress with tunicamycin resulted in an increased expression of Cyclooxygenase 2 (COX-2) and Glucose-regulated protein (GRP78) concomitant with the activation of p38 MAPK/PI3K/Akt in HepG2 cells. Furthermore, the suppression of ER stress with celecoxib or p38 MAPK inhibitor successfully recovered DOX-induced apoptosis. Consistent with the inhibition of COX-2 or p38 MAPK, copretreatment with TM and MLPE drastically recovered cytotoxicity and caspase-3 activation in the presence of DOX. These results reveal that MLPE reduces ER stress-induced resistance to DOX in hepatocellular carcinoma (HCC) cells through downregulation of COX-2- or p38 MAPK-mediated PI3K/Akt pathway.

FSCN‑1 increases doxorubicin resistance in hepatocellular carcinoma through promotion of epithelial-mesenchymal transition.

Resistance to chemotherapy drugs remains a significant problem for the treatment of many types of cancer. Fascin-1 (FSCN-1) is an actin-bundling protein involved in the invasion and metastasis of a variety of tumors. However, its involvement in drug resistance in hepatocellular carcinoma (HCC) remains unclear. The present study aimed to investigate the function of FSCN-1 in HCC resistance to doxorubicin (DOX). FSCN-1 expression was increased in DOX-resistant HCC cell lines (SNU449 and SNU387) compared with DOX-sensitive cell lines (Huh7 and Hep3B). The resistance of HCC cells to DOX was decreased following FSCN-1 knockdown with small interfering RNA. FSCN-1 knockdown also significantly altered the expression of key markers of epithelial-mesenchymal transition (EMT). Notably, vimentin expression was reduced and epithelial-cadherin expression was increased. Furthermore, when EMT was suppressed through knockdown of Twist, an essential pathway of DOX-induced EMT, the viability of HCC cells following treatment with DOX was not affected by FSCN-1 expression. Furthermore, FSCN-1 knockdown eliminated hypoxia-induced doxorubicin resistance and EMT. The results of the present study indicated that FSCN-1 expression increased DOX resistance in HCC cells via the promotion of EMT, and this phenomenon was maintained in a hypoxic environment. FSCN-1 potentially represents a novel target to overcome resistance to DOX in HCC.

MiR-375 delivered by lipid-coated doxorubicin-calcium carbonate nanoparticles overcomes chemoresistance in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a prevalent and lethal disease that is characterized by drug resistance. Doxorubicin (DOX) is a widely used chemotherapeutic drug and miR-375 has been shown to be a tumor suppressor in HCC. Here, we reported that miR-375 and DOX co-loaded into lipid-coated calcium carbonate nanoparticles (LCC-DOX/miR-375 NPs), enhanced the anti-tumor effects through combination therapy, and were highly effective in reversing drug resistance in HCC. LCC-DOX/miR-375 NPs were prepared by a reverse microemulsions method. In vitro, LCC-DOX/miR-375 NPs exhibited enhanced intracellular accumulation, pH-sensitive DOX release and potent cytotoxicity. In vivo, LCC-DOX/miR-375 NPs showed efficient antitumor effect both in xenograft and primary HCC murine models. Our results showed that the LCC-DOX/miR-375 nanoparticles provide a novel strategy to overcome the drug resistance and promote addictive effect between miR-375 and DOX in HCC.

Hepatocyte growth factor/c-Met signaling pathway decreases doxorubicin sensitivity in hepatocellular carcinoma in vitro

Objective To explore the effect of hepatocyte growth factor (HGF)/c-Met signaling in doxorubicin (DOX) treatment of hepatocellular carcinoma (HCC). Methods Different biologic and genetic characteristics human HCC cell lines, Huh7, HepG2, MHCC97-L and MHCC97H were used in this experiment. Variation in c-Met mRNA expression level among different HCC cell lines was analyzed by RT-PCR. Western blot analysis was performed to detect c-Met and p-Met expression levels in these cell lines. CCK-8 experiment was carried to analyze the DOX sensitivity in various cell lines. t test and repeated measure analysis of variance were used for statistical analysis. Results Both c-Met and p-Met were overexpressed in MHCC97-L and MHCC97-H cell lines and these cell lines were resistant to DOX compared to Huh7 and HepG2. However, treatment of HGF in Huh7 and HepG2 cells activated c-Met signaling pathway and decreased the sensitivity of these two cell lines to DOX [inhibition rate: Huh7 (34.848±5.370) vs. (66.409±5.792) %, HepG2 (34.351±3.305) % vs. (62.308±5.453) %, both P = 0.002]. Whereas administration of c-Met inhibitor in MHCC97-L and MHCC97-H cell lines significantly increased the sensitivity to DOX [inhibition rate: MHCC97-L (73.106±3.472) % vs. (13.636±4.097) %; MHCC97-H (64.444±4.006) % vs. (6.296±2.796) %, both P < 0.001]. Conclusion HGF/c-Met signaling pathway is related the treatment efficacy of DOX in HCC. Key words: Carcinoma, hepatocellular; Hepatocyte growth factor; Doxorubicin; Signal transduction

Valproic Acid Induces Endocytosis-Mediated Doxorubicin Internalization and Shows Synergistic Cytotoxic Effects in Hepatocellular Carcinoma Cells.

Valproic acid (VPA), a well-known histone deacetylase (HDAC) inhibitor, is used as an anti-cancer drug for various cancers, but the synergistic anti-cancer effect of VPA and doxorubicin (DOX) combination treatment and its potential underlying mechanism in hepatocellular carcinoma (HCC) remain to be elucidated. Here, we evaluate the mono- and combination-therapy effects of VPA and DOX in HCC and identify a specific and efficient, synergistic anti-proliferative effect of the VPA and DOX combination in HCC cells, especially HepG2 cells; this effect was not apparent in MIHA cells, a normal hepatocyte cell line. The calculation of the coefficient of drug interaction confirmed the significant synergistic effect of the combination treatment. Concurrently, the synergistic apoptotic cell death caused by the VPA and DOX combination treatment was confirmed by Hoechst nuclear staining and Western blot analysis of caspase-3 and poly (ADP-ribose) polymerase (PARP) activation. Co-treatment with VPA and DOX enhanced reactive oxygen species (ROS) generation and autophagy, which were clearly attenuated by ROS and autophagy inhibitors, respectively. Furthermore, as an indication of the mechanism underlying the synergistic effect, we observed that DOX internalization, which was induced in the VPA and DOX combination-treated group, occurred via by the caveolae-mediated endocytosis pathway. Taken together, our study uncovered the potential effect of the VPA and DOX combination treatment with regard to cell death, including induction of cellular ROS, autophagy, and the caveolae-mediated endocytosis pathway. Therefore, these results present novel implications in drug delivery research for the treatment of HCC.

High expression of TRIM44 is associated with enhanced cell proliferation, migration, invasion, and resistance to doxorubicin in hepatocellular carcinoma.

Dysregulation of TRIM44 has been reported to be involved in tumorigenesis, but its role in hepatocellular carcinoma (HCC) remains unclear. In the present study, we investigated the clinicopathological and biological significance of TRIM44 in HCC. We found that TRIM44 mRNA and protein expression was upregulated in HCC compared with matched normal tissues. Intriguingly, we also found that TRIM44 expression was significantly correlated with tumor size (P<0.001), vascular invasion (P<0.001), intrahepatic metastasis (P<0.001), distant metastasis (P<0.001), and Ki-67 expression (P<0.001). Kaplan-Meier analysis showed that high TRIM44 staining was significantly correlated with shorter overall survival (P<0.001). TRIM44 was an independent predictor of overall survival in patients with HCC. Furthermore, we found that ectopic expression of TRIM44 could promote cell proliferation via accelerating the G1/S-phase transition in HCC. Moreover, overexpression of TRIM44 could enhance the invasive and migratory capacity of HCC cells. Meanwhile, we found that high expression of TRIM44 could enhance resistance of HCC cells to doxorubicin via accelerating NF-κB activation. In conclusion, our results suggest that TRIM44 may be a novel prognostic indicator and potential therapeutic target of HCC.

Abstract 2143: Mechanistic study of the relative cytotoxicity of doxorubicin loaded nanoparticle formulation compared to free doxorubicin in hepatocellular carcinoma (HCC) cell lines

Abstract Background and Aims Efficacy of doxorubicin encapsulated into a biodegradable network (NP) is currently studied in phase III compared to Best Standard of Care in patients with advanced HCC (Relive study). Preclinical studies demonstrated that NP allowed the reversion of chemo-resistance and enhanced cytotoxicity compared to free doxorubicin on resistant human hepatoma and mestastatic liver cells. In this study the mechanism of action of NP in overcoming HCC cellular resistance as well as the mechanisms of cellular uptake were investigated in representative cell lines. Methods Determination of IC20 of NP in the presence of influx drug inhibitors targeting endocytosis (clathrin or caveolae-dependent; sucrose and Genistein respectively), phagocytosis (LY-294002) or macropinocytosis (Cytochalasin D) were performed on two HCC cell lines (HuH7 and HepG2) using a proliferation assay. Each uptake inhibitor was added 30 min before incubation with NP on cultured cells for measurement of proliferation followed by cellular quantification of free doxorubicin by HPLC. The same assays were also performed using Verapamil as an inhibitor of the major multidrug resistance protein P-glycoprotein (P-gp). The P-gp ATPase activity in plasma membrane preparations from vehicle, doxorubicin and NP-treated cells was determined using the Pgp-Glo assay system. Results NP showed lower IC20 than free doxorubicin in HCC proliferation assays. None of the influx inhibitors used in combination with NP impaired the inhibitory effect of NP on the rate of proliferation of HCC cell lines. Similarly, Verapamil did not modulate the cellular potency of NP on the rate of proliferation in these cell lines. Doxorubicin quantification in cellular extracts and supernatant of NP-treated cells confirmed these results. Furthermore, NP had no effect on P-gp ATPase activity in isolated plasma membrane samples. Conclusions All these results demonstrated that NP did not enter into the HCC cell via an active transport mechanism, but by passive diffusion as occurs with free Doxorubicin. The absence of inhibition of the P-gp ATPase by NP implies that the Doxorubicin-nanoparticle conjugate (ion pair) probably ‘hinders’ the doxorubicin from being a substrate for the pump rather than by a direct interaction. The implication of these data on the role of NP in the treatment of HCC will be discussed. Citation Format: Véronique Trochon-joseph, Caroline Lemarchand, Vincent Hayes, Yamina Rayah, Jean-Louis Labernardière, Graham Dixon. Mechanistic study of the relative cytotoxicity of doxorubicin loaded nanoparticle formulation compared to free doxorubicin in hepatocellular carcinoma (HCC) cell lines. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2143.

WP1130 increases doxorubicin sensitivity in hepatocellular carcinoma cells through usp9x-dependent p53 degradation

Resistance to chemotherapeutic drugs is a major obstacle in hepatocellular carcinoma (HCC) therapy. However, the underlying mechanisms are not well understood. Recent evidence suggests that deubiquitinases (DUB) are key regulators in the mechanisms of cell proliferation, apoptosis and chemoresistance. The present study aimed to investigate whether WP1130, which inhibits activity of deubiquitinases, exerts synergistic cytotoxicity with doxorubicin in HCC and the underlying mechanisms. In the study, we found that Huh7, HepG2, and SNU387 HCC cells with p53 expression displayed enhanced response to the combination therapy compared with p53-deficient HCC cells (Hep3B) in the manner of inhibiting cell proliferation. Downregulation of p53 abolished the synergistic cytotoxicity of doxorubicin and WP1130 on HCC cells. Mechanistically, we found that combined treatment with WP1130 suppressed doxorubicin-mediated upregulation of p53 via promoting its ubiquitin-proteasome dependent degradation, whereas knockdown of DUB usp9x abolished this effect. Taken together, these results demonstrate that combined treatment with WP1130 sensitized HCC cells to doxorubicin via usp9x-depedent p53 degradation.

High CHMP4B expression is associated with accelerated cell proliferation and resistance to doxorubicin in hepatocellular carcinoma.

Charged multivesicular body protein 4B (CHMP4B), a subunit of the endosomal sorting complex required for transport (ESCRT)-III complex, plays an important part in cytokinetic membrane abscission and the late stage of mitotic cell division. In this study, we explored the prognostic significance of CHMP4B in human hepatocellular carcinoma (HCC) and its impact on the physiology of HCC cells. Western blot and immunohistochemistrical analyses showed that CHMP4B was significantly upregulated in HCC tissues, compared with adjacent non-tumorous tissues. Meanwhile, clinicopathological analysis revealed that high CHMP4B expression was correlated with multiple clinicopathological variables, including AFP, cirrhosis, AJCC stage, Ki-67 expression, and poor prognosis. More importantly, univariate and multivariate survival analyses demonstrated that CHMP4B served as an independent prognostic factor for survival of HCC patients. Using HCC cell cultures, we found that the expression of CHMP4B was progressively upregulated after the release from serum starvation. To verify whether CHMP4B could regulate the proliferation of HCC cells, CHMP4B was knocked down through the transfection of CHMP4B-siRNA oligos. Flow cytometry and CCK-8 assays indicated that interference of CHMP4B led to cell cycle arrest and proliferative impairment of HCC cells. Additionally, depletion of CHMP4B expression could increase the sensitivity to doxorubicin in HepG2 and Huh7 cells. Taken together, our results implied that CHMP4B could be a promising prognostic biomarker as well as a potential therapeutic target of HCC.