Clinical study on conversion therapy of hepatocellular carcinoma - summary and comparison of clinical data from a single center of consecutive four years.

AIM: The purpose of this study was to interpret real-world clinical data to analyze the surgical safety and survival outcomes of patients with initial unresectable hepatocellular carcinoma (uHCC) after conversion therapy. METHODS: A retrospective analysis was performed on 2984 hepatocellular carcinoma (HCC) patients hospitalized in Shandong Cancer Hospital Affiliated to Shandong First Medical University from June 1st, 2019 to June 1st, 2023. Clinicopathological features, response to systemic and/or loco-regional treatments, surgical resection rate after conversion therapy, surgical safety, and postoperative recurrence were analyzed. RESULTS: A total of 38 patients were successfully converted to obtain surgical resection. 35 patients underwent radical resection. A high objective response rate (ORR) (52.6% under RECIST v1.1 and 78.9% under mRECIST criteria) was observed in patients under conversion therapy, and the disease control rate (DCR) was 100%. Pathologic complete response (pCR) was 42.9%. Treatment-related adverse events (TRAEs) of any grade were observed in 37 patients (97.4%). Safety of conversion or direct surgery continues to improve. The median follow-up time was 19.3 months. The 1-year Disease-free survival (DFS) rate of patients with direct surgery and patients with conversion surgery were 91.4% and 86.8%, respectively. CONCLUSIONS: With conversion therapy, a small percentage (1.81%) of uHCC patients are likely to be converted to radical resection. Local combined systemic therapy is a relatively safe and effective conversion therapy, and the safety of surgery is gradually improved after successful conversion. Preliminary follow-up data showed satisfactory survival benefits for patients undergoing conversion surgery. TRIAL REGISTRATION: This was a retrospective study and it did not interfere with treatment decisions.

Real-world practice of conversion surgery for unresectable hepatocellular carcinoma - a single center data of 26 consecutive patients.

AIM: To understand the proportion of uHCC (unresectable hepatocellular carcinoma) patients who achieve successful conversion resection in a high-volume setting with state of the art treatment options. METHODS: We retrospectively reviewed all HCC patients hospitalized to our center from June 1st, 2019 to June 1st, 2022. Conversion rate, clinicopathological features, response to systemic and/or loco-regional therapy and surgical outcomes were analyzed. RESULTS: A total of 1,904 HCC patients were identified, with 1672 patients receiving anti-HCC treatment. 328 patients were considered up-front resectable. Of the remaining 1344 uHCC patients, 311 received loco-regional treatment, 224 received systemic treatment, and the remainder (809) received combination systemic plus loco-regional treatment. Following treatment, one patient from the systemic group and 25 patients from the combination group were considered to have resectable disease. A high objective response rate (ORR) was observed in these converted patients (42.3% under RECIST v1.1 and 76.9% under mRECIST criteria). The disease control rate (DCR) reached 100%. 23 patients underwent curative hepatectomy. Major post-operative morbidity was equivalent in the both groups (P=0.76). Pathologic complete response (pCR) was 39.1%. During conversion treatment, grade 3 or higher treatment-related adverse events (TRAEs) were observed in 50% of patients. The median follow-up time was 12.9 months (range, 3.9~40.6) from index diagnosis and 11.4 months (range, 0.9~26.9) from resection. Three patients experienced disease recurrence following conversion surgery. CONCLUSIONS: By intensive treatment, a small sub-group of uHCC patients (2%) may potentially be converted to curative resection. Loco-regional combined with systemic modality was relative safe and effective in the conversion therapy. Short-term outcomes are encouraging, but long-term follow-up in a larger patient population are required to fully understand the utility of this approach.

Verteporfin suppresses cell survival, angiogenesis and vasculogenic mimicry of pancreatic ductal adenocarcinoma via disrupting the YAP-TEAD complex.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive human malignancies. The Yes-associated protein-1 (YAP) plays a critical role in cell proliferation, apoptosis and angiogenesis. Verteporfin is a photosensitizer used in photodynamic therapy and also a small molecular inhibitor of the Hippo-YAP pathway. However, little is known about whether verteporfin could inhibit YAP activity in PDAC cells. Our present results showed that verteporfin suppressed the proliferation of human PDAC PANC-1 and SW1990 cells by arresting cells at the G1 phase, and inducing apoptosis in dose- and time-dependent manners. Verteporfin also inhibited the tumor growth on the PDAC xenograft model. Treatment with verteporfin led to downregulation of cyclinD1 and cyclinE1, modulation of Bcl-2 family proteins and activation of PARP. In addition, verteporfin exhibited an inhibitory effect on angiogenesis and vasculogenic mimicry via suppressing Ang2, MMP2, VE-cadherin, and α-SMA expression in vitro and in vivo. Mechanism studies demonstrated that verteporfin impaired YAP and TEAD interaction to suppress the expression of targeted genes. Our results provide a foundation for repurposing verteporfin as a promising anti-tumor drug in the treatment of pancreatic cancer by targeting the Hippo pathway.

Lentiviral vector mediated expression of Bax and hepatocyte growth factor inhibits vein graft thickening in a rabbit vein graft model.

Vein graft failure caused by vein graft thickening of the arterialized vein after bypass surgery is a main problem in clinical vascular surgery. Gene therapy is increasingly being recognized as a relevant treatment option for vein graft failure. In this study, we aimed to develop a novel recombinant lentivirus for the delivery of hepatocyte growth factor (HGF) and Bax in a rabbit vein graft model of bypass grafting. A bypass model was made in rabbits using the right jugular vein interposed end-to-end to the ipsilateral carotid artery. A lentivirus vector harboring HGF and Bax cDNAs (Lenti-HGF-Bax) was constructed and transduced into the venous grafts. Vein grafts were stained with hematoxilyn and eosin, and Masson. HGF and Bax expression in vein grafts was detected by immunohistochemical and Western blot analysis. Our results showed that vein graft thickening was reduced by 47.2 ± 7.4% in lenti-HGF-Bax treated rabbits, compared to controls. Meanwhile, the ratio of intima/media area was reduced in lentil-HGF-Bax treated rabbits, compared to controls. The number of HGF and Bax positive cells was increased in vein grafts from rabbits treated by lenti-HGF-Bax, compared to those from controls. Furthermore, protein levels of HGF and Bax were both significantly increased in grafts derived from rabbits treated by lenti-HGF-Bax, compared to those from control. In conclusion, Lenti-HGF-Bax inhibits vein graft thickening in vein grafts and is a promising agent for preventing vein graft failure.

Achieving complete remission in metastatic hepatocellular carcinoma with sintilimab plus sorafenib therapy followed by hepatic resection: a case report.

Background: The synergistic effectiveness of combining immune checkpoint inhibitors with targeted therapies has shown promise in improving the conversion rate for unresectable hepatocellular carcinoma (HCC) patients to a potentially resectable status. However, the efficacy of this approach in the context of HCC with extrahepatic metastasis remains to be conclusively determined. Case presentation: We report a rare case of advanced HCC with extrahepatic metastasis who achieved long-term survival by a combination of systemic therapy (sintilimab and sorafenib) followed by laparoscopic hepatectomy. A 63-year-old man presented at our hospital with discomfort on the right side of his waist. An enlarged right hepatic lobe mass was subsequently revealed by CT scan. The patient's medical history, including a prior infection with hepatitis B virus, cirrhosis of the liver and an alpha-fetoprotein (AFP) level measuring 41.28 ng/ml substantiated the clinical diagnosis of HCC. On October 30th, 2019, the patient received 200 mg sintilimab intravenously (q3w) plus 200-400 mg BID sorafenib orally, along with antiviral therapy. After six cycles, his disease achieved partial response (PR). On April 26th, 2021, He underwent a laparoscopic hepatectomy. The patient achieved a sustained period of no evidence of disease for 2.5 years and with drug-free survival for 2 years after the resection. His current overall survival is estimated at approximately 4 years. Conclusions: This case highlights the potential of combining sintilimab and sorafenib in transforming HCC with extrahepatic metastasis into a condition amenable to surgical resection, suggesting that this treatment approach, followed by surgery, may lead to complete remission.

Analysis of efficacy and safety for the combination of tislelizumab and regorafenib in advanced hepatocellular carcinoma: A prospective clinical study.

BACKGROUNDS: Programmed death receptor 1 (PD-1) monoclonal antibody has been approved for the first and second-line treatments of hepatocellular carcinoma (HCC). This study aimed to evaluate the efficacy and safety of tislelizumab + regorafenib as a second-line treatment option for advanced HCC. METHODS: Treatment-related adverse events (TRAEs) were the primary endpoints in this clinical trial comprising 28 patients with advanced HCC. The secondary endpoints included objective response rate (ORR), disease control rate (DCR), and progression-free survival (PFS). RESULTS: According to the mRECIST 1.1 evaluation criteria, the ORR was 28.6%. Complete and partial response were observed in 3 and 5 patients, respectively; stable disease was observed in 12 patients (DCR, 71.4%). The median PFS was 6.4 months. The incidence of grade 1-2 and 3-4 TRAEs was 57.1% and 39.3%, respectively. CONCLUSION: This study suggests that tislelizumab + regorafenib can be used as a second-line treatment for advanced HCC.

[Corrigendum] T7 peptide inhibits angiogenesis via downregulation of angiopoietin­2 and autophagy.

Following the publication of this article, an interested reader drew to the authors' attention that two pairs of protein bands featured in the western blots in Fig. 3A and 5D on p. 679 and 681 respectively appeared to be strikingly similar. After having re­examined their original data, the authors realized that Fig. 5D had been assembled incorrectly. The revised version of Fig. 5, now including the correct data for Fig. 5D, is shown on the next page. Note that the errors made in terms of assembling the data in Fig. 5 did not greatly affect either the results or the conclusions reported in this paper, and all the authors agree to the publication of this corrigendum. The authors regret that these errors went unnoticed prior to the publication of their article, are grateful to the Editor of Oncology Reports for allowing them this opportunity to publish this corrigendum. They also apologize to the readership for any inconvenience caused. [Oncology Reports  33: 675­684, 2015; DOI: 10.3892/or.2014.3653].

Neoadjuvant tislelizumab plus stereotactic body radiotherapy and adjuvant tislelizumab in early-stage resectable hepatocellular carcinoma: the Notable-HCC phase 1b trial.

Notable-HCC (NCT05185531) is a phase 1b trial, aiming to evaluate the safety and preliminary effectiveness of neoadjuvant PD-1 blockade plus stereotactic body radiotherapy (SBRT) in early-stage resectable hepatocellular carcinoma (HCC). Twenty patients with HCC of BCLC stage 0-A received 3 × Gy SBRT and two cycles of tislelizumab, an anti-PD-1 monoclonal antibody before the curative HCC resection. Primary endpoints were the surgery delay, radiographic and pathological tumor response after the neoadjuvant therapy, safety and tolerability. During the neoadjuvant therapy, treatment-related adverse events (TRAEs) of grade 1-2 occurred in all 20 patients (100%), eight patients (40%) had grade 3 TRAEs, no grade 4 to 5 TRAE occurred, and all resolved without corticosteroids treatment. Per mRECIST, the objective response rate was 63.2% (12/19), with 3 complete response; the disease control rate was 100%. Two (10.5%) patients achieved complete pathological response. No surgery delay occurred. The neoadjuvant therapy did not increase the surgical difficulty or the incidence of complications. Secondary endpoints of disease-free survival and overall survival were not mature at the time of the analysis. Our pilot trial shows that neoadjuvant therapy with anti-PD-1 + SBRT is safe and promotes tumor responses in early-stage resectable HCC.

Significance of the POSSUM scoring system in predicting morbidity and mortality in elderly patients after pancreatoduodenectomy.

BACKGROUND/AIMS: To explore the significance of POSSUM scoring system (Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity) in predicting morbidity and mortality in elderly Chinese patients undergoing pancreatoduodenectomy (PD). METHODOLOGY: Between January 2001 and January 2011, 396 patients underwent PD in our hospital; POSSUM and P-POSSUM score were retrospectively calculated for each patient and correlated with observed morbidity and mortality, respectively. RESULTS: The mortality and morbidity rates were 4.11% and 42.8%, respectively. The POSSUM showed "good fit" in morbidity prediction (p=0.103), it also showed "good fit" in mortality prediction but only in elderly patients (p=0.078). While in young patients, POSSUM showed "poor fit" in both morbidity (p=0.002) and mortality (p=0.012) prediction. CONCLUSIONS: The POSSUM showed significance in predicting morbidity and mortality in elderly Chinese patients, and is helpful in guiding surgical management decisions. A modified equation for POSSUM scoring system based on large-scale clinical PD data should be developed to achieve a better fit in low-risk patients.

Surgical repair of an aortico-left ventricular tunnel with Takayasu's arteritis.

Aortico-left ventricular tunnel is a very rare congenital cardiac anomaly, always arises from the right coronary sinus and enters the left ventricle. However, aortico-left ventricular tunnel associated with Takayasu's arteritis has not been described so far in the literature. Here, we present an unusual case of aortico-left ventricular tunnel associated with Takayasu's arteritis in a 44-year-old man.

Protocol of notable-HCC: a phase Ib study of neoadjuvant tislelizumab with stereotactic body radiotherapy in patients with resectable hepatocellular carcinoma.

INTRODUCTION: Liver resection is the mainstay of curative-intent treatment for hepatocellular carcinoma (HCC), but the postoperative 5-year recurrence rate reaches 70%, and there are no adjuvant or neoadjuvant therapies recommended by major HCC guidelines that can reduce the risk of recurrence. In the recent decade, significant progress has been achieved in the systemic treatment of HCC, mainly from immune checkpoint inhibitors (ICIs) and targeted therapy. In other malignancies, ICIs in the neoadjuvant setting have shown better outcomes than in the adjuvant setting. On the other hand, the addition of radiation to ICIs incrementally improves the systemic response to ICIs. Neoadjuvant therapy of ICIs plus stereotactic body radiotherapy (SBRT) has shown promising results in several types of solid tumours but not HCC. METHODS AND ANALYSIS: Here, we describe a phase Ib clinical trial of neoadjuvant SBRT plus PD-1 (tislelizumab) prior to hepatic resection in HCC patients. Prior to resection, eligible HCC patients will receive 8 Gy×3 fractions of SBRT together with two cycles of tislelizumab with an interval of 3 weeks. HCC resection is scheduled 4 weeks after the second dose of tislelizumab, followed by adjuvant tislelizumab for 1 year. We plan to enrol 20 participants in this trial. The primary study endpoints include the delay of surgery, tumour response and safety and tolerability of the sequential SBRT/tislelizumab. Other endpoints are the disease-free survival and overall survival rates every 3 or 6 months after the surgery. ETHICS AND DISSEMINATION: This trial was approved by the Ethics Committee of Shandong Cancer Hospital and Institute (SDZLEC2022-021-01). The final results of this trial will be published in a peer-reviewed journal after completion. TRIAL REGISTRATION NUMBER: NCT05185531.

The clinical significance of microvascular invasion in the surgical planning and postoperative sequential treatment in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the most common and most lethal malignant tumors in the world. Microvascular invasion (MVI) is a major risk factor for survival outcomes and intrahepatic metastasis after resection in patients with HCC. Relevant English literatures retrieved using PubMed on the research progress of MVI in patients with HCC were reviewed. For HCC patients, especially those with MVI, it is very important to develop a comprehensive and sequential treatment plan to support the long-term survival of patients. This manuscript reviewed and analyzed the risk factors for MVI; the preoperative prediction of MVI, which informs the selection of surgical strategies; and the current situation and future direction of comprehensive postoperative treatment strategies; to provide a basis for the comprehensive treatment of HCC patients with MVI. For HCC patients with MVI, the preoperative prediction of MVI may play a certain guiding role in planning procedures, and the comprehensive sequential postoperative pathological detection of HCC MVI may provide a basis for treatment decisions.

Targeting of the COX-2/PGE2 axis enhances the antitumor activity of T7 peptide in vitro and in vivo.

T7 peptide is considered as an antiangiogenic polypeptide. The presents study aimed to further detect the antiangiogenic mechanisms of T7 peptide and determine whether combining T7 peptide and meloxicam (COX-2/PGE2 specific inhibitor) could offer a better therapy to combat hepatocellular carcinoma (HCC). T7 peptide suppressed the proliferation, migration, tube formation, and promoted the apoptosis of endothelial cells under both normoxic and hypoxic conditions via integrin α3ß1 and αvß3 pathways. Cell proliferation, migration, apoptosis, or tube formation ability were detected, and the expression of integrin-associated regulatory proteins was detected. The anti-tumor activity of T7 peptide, meloxicam, and their combination were evaluated in HCC tumor models established in mice. T7 peptide suppressed the proliferation, migration, tube formation, and promoted the apoptosis of endothelial cells under both normoxic and hypoxic conditions via integrin α3ß1 and αvß3 pathways. Meloxicam enhanced the activity of T7 peptide under hypoxic condition. T7 peptide partly inhibited COX-2 expression via integrin α3ß1 not αvß3-dependent pathways under hypoxic condition. T7 peptide regulated apoptosis associated protein through MAPK-dependent and -independent pathways under hypoxic condition. The MAPK pathway was activated by the COX-2/PGE2 axis under hypoxic condition. The combination of T7 and meloxicam showed a stronger anti-tumor effect against HCC tumors in mice. The data highlight that meloxicam enhanced the antiangiogenic activity of T7 peptide in vitro and in vivo.

Performance Characterization of Semi-Flexible Composite Mixture.

Semi-flexible composite mixture (SFCM) is developed based on a unique material design concept of pouring cement mortar into the voids formed by open graded asphalt mixture. It combines the flexibility of asphalt concrete and the stiffness of Portland cement concrete and has many advantages comparing to conventional roadway paving materials. The main objective of this paper was to evaluate the engineering properties of SFCM and assess the constructability of the SFCM. A slab SFCM sample was fabricated in the laboratory to simulate the filling of cement mortar in the field. Performance testing was carried out by indirect tensile (IDT) test because it was found to be able to correlate with the field performance of asphalt mixtures at low, intermediate, and high temperatures. They were used in this study to evaluate the thermal cracking, fatigue, rutting, as well as moisture resistance of SFCM. A control hot mix asphalt (HMA) mixture was used to compare with the results of SFCM. Based on the testing results, it was found that the designed SFCM showed good filling capability of cement mortar. SFCM had higher dynamic modulus than the control HMA. It had good resistance to rutting and moisture damage. Based on fracture work, SFCM showed better resistance to thermal cracking while lower resistance to fatigue cracking.

Meloxicam, a Selective COX-2 Inhibitor, Mediates Hypoxia-Inducible Factor- (HIF-) 1α Signaling in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is regarded as a leading cause of cancer-related deaths, and its progression is associated with hypoxia and the induction of hypoxia-inducible factor (HIF). Meloxicam, a selective cyclooxygenase-2 (COX-2) inhibitor, induces cell death in various malignancies. However, the underlying mechanism remains to be elucidated in HCC, especially under hypoxic conditions. The alteration of COX-2 and HIF-1α oncogenicity was evaluated in HCC specimens by tissue microarray. Cell viability, angiogenesis assays, and xenografted nude mice were used to evaluate the effects of meloxicam, along with flow cytometry to detect the cell cycle, apoptosis, and mitochondrial membrane potential (ΔΨm) of HCC. qRT-PCR, Western blotting, immunofluorescence, immunohistochemistry, luciferase assay, and RNAi were carried out to determine the HIF-1α signaling affected by meloxicam. In this study, we showed that meloxicam exerts antiproliferative and antiangiogenesis efficacy in vitro and in vivo and causes disruption of mitochondrial membrane potential (ΔΨm), thus leading to caspase-dependent apoptosis under hypoxic environments. Exposure to meloxicam significantly reduced HIF-1α transcriptional activation and expression through sequestering it in the cytoplasm and accelerating degradation via increasing the von Hippel-Lindau tumor suppressor protein (pVHL) in HCC. These data demonstrated that inhibition of HIF-1α by meloxicam could suppress angiogenesis and enhance apoptosis of HCC cells. This discovery highlights that COX-2 specific inhibitors may be a promising therapy in the treatment of HCC.

T7 peptide cytotoxicity in human hepatocellular carcinoma cells is mediated by suppression of autophagy.

The T7 peptide, an active fragment of full­length tumstatin [the non­collagenous 1 domain of the type IV collagen α3 chain, α3 (IV) NC1], has exhibited potential antitumor effects in several types of cancer cells. However, the mechanism underlying its action against human hepatocellular carcinoma (HCC) remains unclear. The present study aimed to investigate the role of autophagy in T7 peptide­induced cytotoxicity in HCC cells in vitro and in vivo. The results revealed that the T7 peptide significantly reduced cell viability and induced cell cycle arrest in HCC cells. The T7 peptide induced apoptosis in HCC cells through upregulation of Bax, Fas, and Fas ligand, and through upregulation of the anti­apoptotic protein Bcl­2. In addition, treatment with the T7 peptide induced protective autophagy in HCC cells. Blocking autophagy by 3­methyladenineor bafilomycin A1 enhanced T7 peptide­induced apoptosis. Furthermore, co­treatment with MK­2206 (an Akt specific inhibitor) or rapamycin (an inhibitor of mTOR) enhanced T7 peptide­induced autophagy, whereas co­treatment with insulin (an activator of the Akt/mTOR signaling pathway) alleviated T7 peptide­induced autophagy, which suggested that the T7 peptide may induce autophagy activation via inhibition of the Akt/mTOR signaling pathway. Taken together, the present results demonstrated that suppression of autophagy potentiated the cytotoxic effects of the T7 peptide, and suggested that the T7 peptide may serve as a potential alternative compound for HCC therapy.

Downregulation of secreted clusterin potentiates the lethality of sorafenib in hepatocellular carcinoma in association with the inhibition of ERK1/2 signals.

Secretory clusterin (sCLU) is overexpressed in cancer and is associated with resistance to chemotherapy in several types of cancer, including hepatocellular carcinoma (HCC). Sorafenib (SOR), a multikinase inhibitor of Raf/mitogen­activated protein kinase kinase/extracellular signal­regulated kinase (ERK) signaling and the receptor tyrosine kinase, is recognized as the standard therapeutic strategy for patients with advanced HCC. However, the role of sCLU in the resistance of HCC to SOR remains to be fully elucidated. In the present study, sCLU was silenced by CLU short hairpin (sh)RNA in Bel­7402 and SMMC­7721 cell lines, following which the cells were treated with SOR. Cell proliferation was determined using a CCK­8 assay. Apoptosis was quantified using flow cytometry. The production of sCLU, B­cell lymphoma 2 (Bcl­2), Bcl­2­associated X sprotein and phosphorylated (p)ERK1/2 was analyzed using western blot analysis. The results showed that sCLU was overexpressed in three HCC cell lines. The downregulation of sCLU by CLU shRNA synergistically increased SOR sensitivity in the Bel­7402 and SMMC­7721 cells, and potentiated SOR­induced cell apoptosis. In addition, silencing sCLU or combination with PD98059 decreased the SOR­induced activation of pERK1/2. These findings indicate a novel treatment strategy for HCC.

Therapeutic role of meloxicam targeting secretory clusterin-mediated invasion in hepatocellular carcinoma cells.

Recurrence and metastasis are the two leading causes of poor prognosis in patients with hepatocellular carcinoma (HCC). Secreted clusterin (sCLU) is a stress-induced chaperone that is overexpressed in HCC. However, the precise molecular mechanisms of sCLU in HCC invasion and migration are largely unknown. In the present study, it was indicated that downregulation of sCLU significantly alleviated invasiveness whereas overexpression of sCLU notably enhanced the number of invasive cells via mediating the expression level of MMP-2 and E-cadherin in Bel-7402 and SMMC-7721 cells. Furthermore, as an important mediator of invasiveness, sCLU may be responsible for proliferation and invasion suppression induced by meloxicam (a selective inhibitor of cyclooxygenase-2) in HCC cells. The combination of meloxicam and CLU shRNA significantly decreased invasion in HCC cells in vitro. Furthermore, it was observed that overexpression of sCLU significantly potentiated expression of p-AKT and MMP-2. However, downregulation of sCLU by CLU shRNA alleviated the extent of p-AKT. These results suggest the targeting of sCLU may be a novel therapeutic strategy against invasion and migration in HCC.

Secretory Clusterin Mediates Oxaliplatin Resistance via the Gadd45a/PI3K/Akt Signaling Pathway in Hepatocellular Carcinoma.

Purpose: Systemic therapy has often been used for patients with advanced hepatocellular carcinoma (HCC). However, due to drug resistance, the use of cytotoxic chemotherapy in the treatment of patients with advanced HCC has typically demonstrated low response rates. Secretory clusterin (sCLU) is expressed in aggressive late-stage tumors and associated with resistance to chemotherapy, including that in HCC cases. The present research aimed to investigate the biological role of sCLU in HCC. Methods: sCLU expression in HCC and normal tissues was examined using immunohistochemical staining, followed by analysis of the correlation between sCLU expression and clinical indicators. In addition, the role and internal mechanism of sCLU in cell proliferation and apoptosis were investigated in HCC cells. Results: sCLU expression was significantly upregulated in HCC tissues; and was associated with histological grade and poor overall survival. The levels of sCLU were significantly increased in Bel7402, SMMC7721 and resistant HCC cells (Bel7404-OR). Inhibiting the activity of sCLU enhanced the chemosensitivity of Bel7402 and SMMC7721 cells. Downregulation of sCLU could increase the expression of Gadd45a in HCC cells. Overexpression of sCLU contributed to drug resistance in Bel7402, SMMC7721 and Bel7404-OR cells; whereas, overexpression of Gadd45a alone overcame drug resistance in the cells above. No significant expression changes of sCLU and Gadd45a were observed in HCC cells after the interference of a selective inhibitor of the PI3K/Akt signaling pathway. However, regulation of the expression of Gadd45a could influence the phosphorylation level of Akt; and further regulate the expression of Bcl-2 and Bax proteins involved in the mitochondrial apoptosis pathways. Conclusions: The results demonstrate that sCLU/Gadd45a/PI3K/Akt signaling represents a novel pathway that could regulate drug resistance in a one-way manner in HCC cells.

COX-2/PGE2 Axis Regulates HIF2α Activity to Promote Hepatocellular Carcinoma Hypoxic Response and Reduce the Sensitivity of Sorafenib Treatment.

Purpose: Hypoxia-inducible factor-2α (HIF2α) is regarded as a preferential target for individualized hepatocellular carcinoma (HCC) treatment and sorafenib resistance. Our study aimed to identify the regulatory mechanisms of HIF2α activity under hypoxic conditions. We sought to determine whether the COX-2/PGE2 axis is involved in the regulatory mechanisms of HIF2α activity and of sorafenib resistance in hypoxic HCC cells.Experimental Design: The cell viability, migration, and invasion abilities were measured to analyze the effects of HIF2α on hypoxic HCC cells. Both in vitro and in vivo HCC models were used to determine whether the COX-2/PGE2 axis is a driver of HIF2α level and activity, which then reduces the sensitivity of sorafenib treatment in hypoxic HCC cells.Results: Under hypoxic conditions, the COX-2/PGE2 axis effectively stabilized HIF2α and increased its level and activity via decreasing von Hippel-Lindau protein (p-VHL) level, and also enhanced HIF2α activity by promoting HIF2α nuclear translocation via MAPK pathway. The activation of HIF2α then led to the enhanced activation of VEGF, cyclin D1, and TGFα/EGFR pathway to mediate HCC development and reduce the sensitivity of sorafenib. More importantly, COX-2-specific inhibitors synergistically enhanced the antitumor activity of sorafenib treatment.Conclusions: Our data obtained demonstrate that the COX/PGE2 axis acts as a regulator of HIF2α expression and activity to promote HCC development and reduce sorafenib sensitivity by constitutively activating the TGFα/EGFR pathway. This study highlights the potential of COX-2-specific inhibitors for HCC treatment and particularly for enhancing the response to sorafenib treatment. Clin Cancer Res; 24(13); 3204-16. ©2018 AACR.