Gene therapy for unresectable hepatocellular carcinoma using recombinant human adenovirus type 5

Gene therapy for people with hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma is the most common type of liver cancer, accounting for 70% to 85% of individuals with primary liver cancer. Gene therapy, which uses genes to treat or prevent diseases, holds potential for treatment, especially for tumours. Trials on the effects of gene therapy in people with hepatocellular carcinoma have been published or are ongoing.

OBJECTIVES

To evaluate the benefits and harms of gene therapy in people with hepatocellular carcinoma, irrespective of sex, administered dose, and type of formulation.

SEARCH METHODS

We identified randomised clinical trials through electronic searches in The Cochrane Hepato-Biliary Group Controlled Trials Register, CENTRAL, MEDLINE, Embase, LILACS, Science Citation Index Expanded, and Conference Proceedings Citation Index-Science. We searched five online clinical trial registries to identify unpublished or ongoing trials. We checked reference lists of the retrieved studies for further trials. The date of last search was 20 January 2023.

SELECTION CRITERIA

We aimed to include randomised clinical trials assessing any type of gene therapy in people diagnosed with hepatocellular carcinoma, irrespective of year, language of publication, format, or outcomes reported.

DATA COLLECTION AND ANALYSIS

We followed Cochrane methodology and used Review Manager to prepare the review. The primary outcomes were all-cause mortality/overall survival (whatever data were provided), serious adverse events during treatment, and health-related quality of life. The secondary outcomes were proportion of people with disease progression, adverse events considered non-serious, and proportion of people without improvement in liver function tests. We assessed risk of bias of the included trials using RoB 2 and the certainty of evidence using GRADE. We presented the results of time-to-event outcomes as hazard ratios (HR), dichotomous outcomes as risk ratios (RR), and continuous outcomes as mean difference (MD) with their 95% confidence intervals (CI). Our primary analyses were based on intention-to-treat and outcome data at the longest follow-up.

MAIN RESULTS

We included six randomised clinical trials with 364 participants. The participants had unresectable (i.e. advanced inoperable) hepatocellular carcinoma. We found no trials assessing the effects of gene therapy in people with operable hepatocellular carcinoma. Four trials were conducted in China, one in several countries (from North America, Asia, and Europe), and one in Egypt. The number of participants in the six trials ranged from 10 to 129 (median 47), median age was 55.2 years, and the mean proportion of males was 72.7%. The follow-up duration ranged from six months to five years. As the trials compared different types of gene therapy and had different controls, we could not perform meta-analyses. Five of the six trials administered co-interventions equally to the experimental and control groups. All trials assessed one or more outcomes of interest in this review. The certainty of evidence was very low in five of the six comparisons and low in the double-dose gene therapy comparison. Below, we reported the results of the primary outcomes only. Pexastimogene devacirepvec (Pexa-Vec) plus best supportive care versus best supportive care alone There is uncertainty about whether there may be little to no difference between the effect of Pexa-Vec plus best supportive care compared with best supportive care alone on overall survival (HR 1.19, 95% CI 0.78 to 1.82; 1 trial (censored observation at 20-month follow-up), 129 participants; very low-certainty evidence) and on serious adverse events (RR 1.42, 95% CI 0.60 to 3.33; 1 trial at 20 months after treatment, 129 participants; very low-certainty evidence). The trial reported quality of life narratively as "assessment of quality of life and time to symptomatic progression was confounded by the high patient dropout rate." Adenovirus-thymidine kinase with ganciclovir (ADV-TK/GCV) plus liver transplantation versus liver transplantation alone There is uncertainty about whether ADV-TK/GCV plus liver transplantation may benefit all-cause mortality at the two-year follow-up (RR 0.39, 95% CI 0.20 to 0.76; 1 trial, 45 participants; very low-certainty evidence). The trial did not report serious adverse events other than mortality or quality of life. Double-dose ADV-TK/GCV plus liver transplantation versus liver transplantation alone There is uncertainty about whether double-dose ADV-TK/GCV plus liver transplantation versus liver transplantation may benefit all-cause mortality at five-year follow-up (RR 0.40, 95% CI 0.22 to 0.73; 1 trial, 86 participants; low-certainty evidence). The trial did not report serious adverse events other than mortality or quality of life. Recombinant human adenovirus-p53 with hydroxycamptothecin (rAd-p53/HCT) versus hydroxycamptothecin alone There is uncertainty about whether there may be little to no difference between the effect of rAd-p53/HCT versus hydroxycamptothecin alone on the overall survival at 12-month follow-up (RR 3.06, 95% CI 0.16 to 60.47; 1 trial, 48 participants; very low-certainty evidence). The trial did not report serious adverse events or quality of life. rAd-p53/5-Fu (5-fluorouracil) plus transarterial chemoembolisation versus transarterial chemoembolisation alone The trial included 46 participants. We had insufficient data to assess overall survival. The trial did not report serious adverse events or quality of life. E1B-deleted (dl1520) adenovirus versus percutaneous ethanol injection The trial included 10 participants. It did not report data on overall survival, serious adverse events, or health-related quality of life. One trial did not provide any information on sponsorship; one trial received a national research grant, one trial by the Pedersen foundation, and three were industry-funded trials. We found five ongoing randomised clinical trials.

AUTHORS' CONCLUSIONS

The evidence is very uncertain about the effects of gene therapy on the studied outcomes because of high risk of bias and imprecision of outcome results. The trials were underpowered and lacked trial data on clinically important outcomes. There was only one trial per comparison, and we could not perform meta-analyses. Therefore, we do not know if gene therapy may reduce, increase, or have little to no effect on all-cause mortality or overall survival, or serious adverse events in adults with unresectable hepatocellular carcinoma. The impact of gene therapy on adverse events needs to be investigated further. Evidence on the effect of gene therapy on health-related quality of life is lacking.

Recent advances in oncolytic virus therapy for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a highly refractory cancer and the fourth leading cause of cancer-related mortality worldwide. Despite the development of a detailed treatment strategy for HCC, the survival rate remains unsatisfactory. Oncolytic virus has been extensively researched as a new cancer therapeutic agent in the treatment of HCC. Researchers have designed a variety of recombinant viruses based on natural oncolytic diseases, which can increase the targeting of oncolytic viruses to HCC and their survival in tumors, as well as kill tumor cells and inhibit the growth of HCC through a variety of mechanisms. The overall efficacy of oncolytic virus therapy is known to be influenced by anti-tumor immunity, toxic killing effect and inhibition of tumor angiogenesis, etc. Therefore, a comprehensive review of the multiple oncolytic mechanisms of oncolytic viruses in HCC has been conducted. So far, a large number of relevant clinical trials are under way or have been completed, and some encouraging results have been obtained. Studies have shown that oncolytic virus combined with other HCC therapies may be a feasible method, including local therapy, chemotherapy, molecular targeted therapy and immunotherapy. In addition, different delivery routes for oncolytic viruses have been studied so far. These studies make oncolytic virus a new and attractive drug for the treatment of HCC.

Adenovirus vector-mediated single chain variable fragments target the nucleocapsid protein of porcine epidemic diarrhea virus and protect against viral infection in piglets

Porcine epidemic diarrhea virus (PEDV) mainly infects the intestinal epithelial cells of pigs, causing porcine epidemic diarrhea (PED). In particular, the virus causes severe diarrhea, dehydration, and death in neonatal piglets. Maternal immunity effectively protects neonatal piglets from PEDV infection; however, maternal antibodies can only prevent PEDV attachment and entry into target cells, but have no effects on intracellular viruses. Intracellular antibodies targeting virus-encoded proteins are effective in preventing viral infection. We previously identified four single chain variable fragments (scFvs), ZW1-16, ZW3-21, ZW1-41, and ZW4-16, which specifically targeted the PEDV N protein and significantly inhibited PEDV replication and up-regulated interferon-λ1 (IFN-λ1) expression in host cells. In our current study, the four scFvs were subcloned into replication-defective adenovirus vectors to generate recombinant adenoviruses rAdV-ZW1-16, rAdV-ZW3-21, rAdV-ZW1-41, and rAdV-ZW4-16. ScFvs were successfully expressed in Human Embryonic Kidney 293 (HEK293) cells and intestinal porcine epithelial cell line J2 (IPEC-J2) and were biosafe for piglets as indicated by body temperature and weight, scFv excretion in feces, IFN-γ and interleukin-4 (IL-4) expression in jejunum, and pathological changes in porcine tissue after oral administration. Western blotting, immunofluorescence, and immunohistochemical analyses showed that scFvs were expressed in porcine jejunum. The prophylactic effects of rAdV-ZW, a cocktail of the four rAdV-scFvs, on piglet diarrhea caused by PEDV was investigated. Clinical symptoms in piglets orally challenged with PEDV, following a two-time treatment with rAdV-ZW, were significantly reduced when compared with PEDV-infected piglets treated with phosphate buffered saline (PBS) or rAdV-wild-type. Also, no death and jejunal lesions were observed. ScFv co-localization with the PEDV N protein in vivo was also observed. Next, the expression of pro-inflammatory serum cytokines such as tumor necrosis factor-α (TNF-α), IL-6, IL-8, IL-12, and IFN-λ was assessed by enzyme-linked immunosorbent assay (ELISA), which showed that scFvs significantly suppressed PEDV-induced pro-inflammatory cytokine expression and restored PEDV-inhibited IFN-λ expression. Therefore, our study supported a promising role for intracellular scFvs targeting the PEDV N protein to prevent and treat diarrhea in PEDV-infected piglets.

Prognostic Comparison between cTACE and H101-TACE in Unresectable Hepatocellular Carcinoma (HCC): A Propensity-Score Matching Analysis

Background

Transarterial chemoembolization (TACE) is the most common treatment for patients with HCC who are unsuitable for radical therapies. Conventional TACE (cTACE) takes advantage of the preferential hepatic arterial supply of HCC for the targeted delivery of chemotherapeutic agents suspended in lipiodol, followed by embolization or reduction of arterial flow using various types of particles while sparing the surrounding liver parenchyma. Aims and Objectives. The current study is aimed at comparing the efficacy and safety profiles of transarterial infusion of recombinant human type-5 adenovirus (H101-TACE) with conventional transarterial chemoembolization (cTACE) in patients with unresectable hepatocellular carcinoma (HCC).

Methods

Unresectable HCC patients that received H101-based TACE or cTACE from August 2018 to September 2021 were retrospectively evaluated. Propensity score matching (PSM) has a 1 : 1 ratio to eliminate possible confounder imbalances across cohorts. The main outcome was overall survival (OS), while secondary outcomes were progression-free survival (PFS) and tumor response.

Results

This study included 111 patients classified across two cohorts: the H101-TACE cohort (n = 37) and the cTACE cohort (n = 74). Median OS within the H101-TACE cohort was 9.0 months longer than within the cTACE cohort before PSM (22.1 vs. 13.1 months, P = 0.043) and 9.3 months longer following PSM (22.1 vs. 12.8 months, P = 0.004). The median PFS within the H101-TACE cohort was 3.2 months longer compared to the cTACE cohort before PSM (6.5 vs. 3.3 months, P = 0.046) and 2.5 months after PSM (6.5 vs. 4.0 months, P = 0.012). The disease control rate for H101 and control cohorts was 81.1% and 59.5%, accordingly (P = 0.039).

Conclusion

The present study demonstrated that the H101-TACE is safe and efficient and can considerably enhance prognostic results for unresectable HCC compared to cTACE.

The efficacy and safety of oncolytic viruses in the treatment of intermediate to advanced solid tumors: a systematic review and meta-analysis

Background

Cancer treatment remains one of the most formidable challenges worldwide. Some novel treatment strategies, including molecularly targeted therapy, gene therapy, and cellular immunotherapy, have also been investigated to improve therapeutic effects for cancer patients and have demonstrated unexpected positive effects. This systematic review and meta-analysis evaluated the efficacy and safety of oncolytic virus (OV) monotherapy or combination therapy for intermediate to advanced solid tumors.

Methods

We retrieved articles from PubMed, Embase, Web of Science, CNKI, Wanfang and VIP. The quality of the included studies was assessed by Review Manager Software version 5.3. STATA software was used to perform meta-analyses of efficacy, overall survival (OS) and adverse reactions.

Results

A total of 22 studies involving 3,996 patients were included in this analysis, including 13 H101 studies, 5 T-VEC studies, 2 Pexa-Vec studies, 1 HF10 study and 1 Reolysin study. Regarding oncolytic adenovirus H101, meta-analysis showed that patients treated with H101 monotherapy or H101 combined with chemotherapy had a significantly higher objective response rate (ORR) than those treated with chemotherapy. Patients in the H101 and T-VEC groups had significantly longer effect size (ES) than the control group patients. The odds ratio (OR) and ES of patients with hepatocellular carcinoma, lung cancer and melanoma treated with OV were analyzed. For the safety profile, the total incidence of adverse reactions was similar in both groups. In terms of the other OVs, according to a systematic review, we found that after Reolysin treatment, the ORR was 26.9% in patients with head and neck cancer. The phase I study of HF10 exhibited some therapeutic potential. The adverse events (AEs) associated with the other OVs mainly included fever, nausea and vomiting, leukopenia, and hypotension.

Discussion

OVs are effective and well tolerated for the treatment of intermediate to advanced solid cancer and represent a promising therapeutic approach for solid cancers.

A systematic analysis on the clinical safety and efficacy of onco-virotherapy

Several onco-virotherapy candidates have been developed and clinically evaluated for the treatment of cancer, and several are approved for clinical use. In this systematic review we explored the clinical impact of onco-virotherapy compared to other cancer therapies by analyzing factors such as trial design, patient background, therapy design, delivery strategies, and study outcomes. For this purpose, we retrieved clinical studies from three platforms: ClinicalTrials.gov, PubMed, and EMBASE. We found that most studies were performed in patients with advanced and metastatic tumors, using a broad range of genetically engineered vectors and mainly administered intratumorally. Therapeutic safety was the most frequently assessed outcome, while relatively few studies focused on immunological antitumor responses. Moreover, only 59 out of 896 clinical studies were randomized controlled trials reporting comparative data. This systemic review thus reveals the need of more, and better controlled, clinical studies to increase our understanding on the application of onco-virotherapy either as a single treatment or in combination with other cancer immunotherapies.

Effects of recombinant human adenovirus type 5 combined with transarterial chemoembolization on postoperative metastasis and recurrence of hepatocellular carcinoma patients

BACKGROUND

Postoperative recurrence is currently the main factor affecting the long-term survival of hepatocellular carcinoma (HCC) patients. The folinic acid, fluorouracil, and oxaliplatin (FOLFOX) regimen with transarterial chemoembolization (TACE) is a commonly used postoperative chemotherapy strategy, but its effect is still limited. The aim of this study was to analyze the effects of recombinant human adenovirus type 5 (rhAd5) combined with TACE on postoperative metastasis and recurrence of HCC.

METHODS

Patients with HCC undergoing surgical treatment were collected and divided into the rhAd5 group and control group according to whether rhAd5 was performed. The rhAd5 group was combined with rhAd5 treatment based on TACE. The recurrence and metastasis rates of the two participant groups were compared. The changes of liver function, kidney function, blood routine, and adverse reactions during treatment were analyzed.

RESULTS

The basic data of the two groups were not significantly different (P>0.05). The recurrence and metastasis rates of rhAd5 group participants were significantly lower than those of the control group (P<0.05). There was no significant difference in the incidence of adverse reactions between the rhAd5 group and control group (P>0.05). There were no significant differences in the incidences of adverse reactions between the rhAd5 group and control group (P>0.05).

CONCLUSIONS

The combination of FOLFOX and rhAd5 after surgery can significantly inhibit the occurrence of metastasis and recurrence of HCC patients, improve progression free survival, and has certain safety.

Advanced hepatocellular carcinoma treated by radiofrequency ablation combined with oncolytic virus and anti-PD-1 antibody therapy: a case report and literature review

The development of an effective therapy for advanced hepatocellular carcinoma (HCC) represents an important global concern. In recent years, the combination of multiple treatment methods with immunotherapy has achieved great progress in patients with advanced HCC. Patient survival has been significantly prolonged, but cases of complete response (CR) remain rare. Here, we report two cases in which CR was achieved by radiofrequency ablation combined with an oncolytic virus (recombinant human adenovirus type 5) and anti-programmed cell death protein 1 antibody. Additionally, a literature review is presented to describe similar advancements in this field and explore viable methods for the treatment of advanced HCC.

Combinatorial Approaches for Cancer Treatment Using Oncolytic Viruses: Projecting the Perspectives through Clinical Trials Outcomes

Recent cancer immunotherapy breakthroughs have fundamentally changed oncology and revived the fading hope for a cancer cure. The immune checkpoint inhibitors (ICI) became an indispensable tool for the treatment of many malignant tumors. Alongside ICI, the application of oncolytic viruses in clinical trials is demonstrating encouraging outcomes. Dozens of combinations of oncolytic viruses with conventional radiotherapy and chemotherapy are widely used or studied, but it seems quite complicated to highlight the most effective combinations. Our review summarizes the results of clinical trials evaluating oncolytic viruses with or without genetic alterations in combination with immune checkpoint blockade, cytokines, antigens and other oncolytic viruses as well. This review is focused on the efficacy and safety of virotherapy and the most promising combinations based on the published clinical data, rather than presenting all oncolytic virus variations, which are discussed in comprehensive literature reviews. We briefly revise the research landscape of oncolytic viruses and discuss future perspectives in virus immunotherapy, in order to provide an insight for novel strategies of cancer treatment.

Current Status of Gene Therapy in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common cancer and the second leading cause of cancer related deaths world-wide. Liver transplantation, surgical resection, trans-arterial chemoembolization, and radio frequency ablation are effective strategies to treat early stage HCC. Unfortunately, HCC is usually diagnosed at an advanced stage and there are not many treatment options for late stage HCC. First-line therapy for late stage HCC includes sorafenib and lenvatinib. However, these treatments provide only an approximate three month increase in survival. Besides, they cannot specifically target cancer cells that lead to a wide array of side effects. Patients on these drugs develop resistance within a few months and have to rely on second-line therapy that includes regorafenib, pembrolizumab, nivolumab, and cabometyx. These disadvantages make gene therapy approach to treat HCC an attractive option. The two important questions that researchers have been trying to answer in the last 2-3 decades are what genes should be targeted and what delivery systems should be used. The objective of this review is to analyze the changing landscape of HCC gene therapy, with a focus on these two questions.

Applications of Virus Vector-Mediated Gene Therapy in China

Due to the increased safety and efficiency of virus vectors, virus vector-mediated gene therapy is now widely used for various diseases, including monogenic diseases, complex disorders, and infectious diseases. Recent gene therapy trials have shown significant therapeutic benefits, and Chinese researchers have contributed significantly to this progress. This review highlights disease applications and strategies for virus vector-mediated gene therapy in preclinical studies and clinical trials in China.

Progress and prospects of engineered sequence-specific DNA modulating technologies for the management of liver diseases

Liver diseases are one of the leading causes of mortality in the world. The hepatic illnesses, which include inherited metabolic disorders, hemophilias and viral hepatitides, are complex and currently difficult to treat. The maturation of gene therapy has heralded new avenues for developing effective intervention for these diseases. DNA modification using gene therapy is now possible and available technology may be exploited to achieve long term therapeutic benefit. The ability to edit DNA sequences specifically is of paramount importance to advance gene therapy for application to liver diseases. Recent development of technologies that allow for this has resulted in rapid advancement of gene therapy to treat several chronic illnesses. Improvements in application of derivatives of zinc finger proteins (ZFPs), transcription activator-like effectors (TALEs), homing endonucleases (HEs) and clustered regularly interspaced palindromic repeats (CRISPR) and CRISPR associated (Cas) systems have been particularly important. These sequence-specific technologies may be used to modify genes permanently and also to alter gene transcription for therapeutic purposes. This review describes progress in development of ZFPs, TALEs, HEs and CRISPR/Cas for application to treating liver diseases.

Genetic polymorphisms in antioxidant enzyme genes and susceptibility to hepatocellular carcinoma in Chinese population: a case-control study

An increased oxidant burden has been implicated in hepatocarcinogenesis, and several antioxidant enzymes counteract potential oxidative damage. So, polymorphisms in the genes encoding antioxidant enzymes may play an important role in the development of hepatocellular carcinoma (HCC). To test this hypothesis, we investigated the association of polymorphisms in antioxidant enzyme genes, including three superoxide dismutases (SODs), catalase (CAT), and glutathione peroxidase (GPx), with HCC in a Chinese population consisting of 434 HCC patients and 480 control subjects. Genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Odds ratios (ORs) and 95 % confidence intervals (95 % CIs) were estimated by unconditional logistic regression. For the ECSOD Ala40Thr polymorphism, a significant association was observed between this polymorphism and HCC risk in non-hepatitis B virus (HBV) carriers but not in HBV carriers, and individuals with one 40Thr allele (Ala/Thr genotype) (OR = 2.13, 95 % CI = 1.25-3.64, P = 0.006) or at least one 40Thr allele (Ala/Thr and Thr/Thr genotype) (OR = 1.90, 95 % CI = 1.15-3.15, P = 0.012) showed significantly higher risk to HCC, compared with Ala/Ala genotype. No significant associations were observed between three other polymorphisms (MnSOD Ala16Val, CAT-262C/T, GPx Pro198Leu) and HCC susceptibility in both HBV carriers and non-HBV carriers. Furthermore, no other signs of combined effects, except for a combined effect of ECSOD Ala40Thr and MnSOD Val16Ala in non-HBV carriers, were observed for each combination of these four polymorphisms. In conclusion, our results indicate that the antioxidant enzyme gene polymorphisms at least partially contribute to the susceptibility to HCC.