Prolonged recurrence-free survival following OK432-stimulated dendritic cell transfer into hepatocellular carcinoma during transarterial embolization

Coactivation of innate immune suppressive cells induces acquired resistance against combined TLR agonism and PD-1 blockade

Immune checkpoint blockade therapy has been successfully applied in clinical settings as a standard therapy for many cancer types, but its clinical efficacy is restricted to patients with immunologically hot tumors. Various strategies to modify the tumor microenvironment (TME), such as Toll-like receptor (TLR) agonists that can stimulate innate immunity, have been explored but have not been successful. Here, we show a mechanism of acquired resistance to combination treatment consisting of an agonist for multiple TLRs, OK-432 (Picibanil), and programmed cell death protein 1 (PD-1) blockade. Adding the TLR agonist failed to convert the TME from immunogenically cold to hot and did not augment antitumor immunity, particularly CD8+ T cell responses, in multiple animal models. The failure was attributed to the coactivation of innate suppressive cells, such as polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) expressing CXCR2, through high CXCL1 production by macrophages in the TME upon OK-432 treatment. A triple combination treatment with OK-432, PD-1 blockade, and a CXCR2 neutralizing antibody overcame the resistance induced by PMN-MDSCs, resulting in a stronger antitumor effect than that of any dual combinations or single treatments. The accumulation of PMN-MDSCs was similarly observed in the pleural effusions of patients with lung cancer after OK-432 administration. We propose that successful combination cancer immunotherapy intended to stimulate innate antitumor immunity requires modulation of unwanted activation of innate immune suppressive cells, including PMN-MDSCs.

Current Perspectives of Immunotherapy for Hepatocellular Carcinoma

Hepatocellular carcinoma is the sixth most common tumor and the third leading cause of cancer death worldwide. It ranks fourth in the spectrum of malignant tumor incidence and second in the order of death from major malignant tumors in China. Hepatocellular carcinoma is a complex ecosystem containing non-tumor cells (mainly immune-related cells), and its immunotherapy can stimulate the recognition of specific tumor antigens, inhibit the proliferation of cancer cells, and produce over-memory lymphocytes, which can prevent recurrence. So, immunotherapy of hepatocellular carcinoma is increasingly becoming a research hotspot in liver cancer treatment. With the intensive research in recent years, great progress has been made in immunotherapy for hepatocellular carcinoma, including immune checkpoint inhibitors, pericyte therapy, vaccination, and antiviral therapy. In addition, the study found that the therapeutic effect of combination therapy was enhanced compared to monotherapy. This review summarizes the most prominent immunotherapies currently available for the clinical treatment of patients with HCC and the main opportunities and challenges facing HCC research.

Research Progress on Dendritic Cells in Hepatocellular Carcinoma Immune Microenvironments

Dendritic cells (DCs) are antigen-presenting cells that play a crucial role in initiating immune responses by cross-presenting relevant antigens to initial T cells. The activation of DCs is a crucial step in inducing anti-tumor immunity. Upon recognition and uptake of tumor antigens, activated DCs present these antigens to naive T cells, thereby stimulating T cell-mediated immune responses and enhancing their ability to attack tumors. It is particularly noted that DCs are able to cross-present foreign antigens to major histocompatibility complex class I (MHC-I) molecules, prompting CD8+ T cells to proliferate and differentiate into cytotoxic T cells. In the malignant progression of hepatocellular carcinoma (HCC), the inactivation of DCs plays an important role, and the activation of DCs is particularly important in anti-HCC immunotherapy. In this review, we summarize the mechanisms of DCs activation in HCC, the involved regulatory factors and strategies to activate DCs in HCC immunotherapy. It provides a basis for the study of HCC immunotherapy through DCs activation.

Exploring the role of the immune microenvironment in hepatocellular carcinoma: Implications for immunotherapy and drug resistance

Hepatocellular carcinoma (HCC), the most common type of liver tumor, is a leading cause of cancer-related deaths, and the incidence of liver cancer is still increasing worldwide. Curative hepatectomy or liver transplantation is only indicated for a small population of patients with early-stage HCC. However, most patients with HCC are not candidates for radical resection due to disease progression, leading to the choice of the conventional tyrosine kinase inhibitor drug sorafenib as first-line treatment. In the past few years, immunotherapy, mainly immune checkpoint inhibitors (ICIs), has revolutionized the clinical strategy for HCC. Combination therapy with ICIs has proven more effective than sorafenib, and clinical trials have been conducted to apply these therapies to patients. Despite significant progress in immunotherapy, the molecular mechanisms behind it remain unclear, and immune resistance is often challenging to overcome. Several studies have pointed out that the complex intercellular communication network in the immune microenvironment of HCC regulates tumor escape and drug resistance to immune response. This underscores the urgent need to analyze the immune microenvironment of HCC. This review describes the immunosuppressive cell populations in the immune microenvironment of HCC, as well as the related clinical trials, aiming to provide insights for the next generation of precision immunotherapy.

Molecular mechanisms of TACE refractoriness: Directions for improvement of the TACE procedure

Transcatheter arterial chemoembolisation (TACE) is the standard of care for intermediate-stage hepatocellular carcinoma and selected patients with advanced hepatocellular carcinoma. However, TACE does not achieve a satisfactory objective response rate, and the concept of TACE refractoriness has been proposed to identify patients who do not fully benefit from TACE. Moreover, repeated TACE is necessary to obtain an optimal and sustained anti-tumour response, which may damage the patient's liver function. Therefore, studies have recently been performed to improve the effectiveness of TACE. In this review, we summarise the detailed molecular mechanisms associated with TACE responsiveness and relapse after this treatment to provide more effective targets for adjuvant therapy while helping to improve TACE regimens.

Immunoembolization for the Treatment of Uveal Melanoma Hepatic Metastases

Uveal melanoma is the most common primary intraocular tumor in adults. Approximately 50% of patients develop metastatic disease despite successful treatment of the primary eye tumor. The liver is the most common site of metastatic disease occurring in more than 90% of patients. Clinical prognosis is dependent on the ability to control the growth of liver tumors. Locoregional therapies play an important role in stabilizing liver metastases, prolonging survival for patients with metastatic uveal melanoma. As overall survival is prolonged, the development of extrahepatic disease becomes more common. Immunoembolization, a form of liver-directed therapy, not only focuses on treating hepatic metastases by stimulating the local immune system to suppress the growth of liver tumors, but it potentially generates a systemic immune response delaying the growth of extrahepatic metastases as well. The following article discusses immunoembolization for the treatment of metastatic uveal melanoma including the rationale, mechanism of action, indications, contraindications, outcomes, and associated toxicities.

Injectable hydrogel loaded with lysed OK-432 and doxorubicin for residual liver cancer after incomplete radiofrequency ablation

OBJECTIVE

To investigate the efficacy of an injectable hydrogel loaded with lysed OK-432 (lyOK-432) and doxorubicin (DOX) for residual liver cancer after incomplete radiofrequency ablation (iRFA) of hepatocellular carcinoma (HCC), and explore the underlying mechanism.

MATERIALS AND METHODS

The effect of OK-432 and lyOK-432 was compared in activating dendritic cells (DCs). RADA16-I (R) peptide was dissolved in a mixture of lyOK-432 (O) and DOX (D) to develop an ROD hydrogel. The characteristics of ROD hydrogel were evaluated. Tumor response and mice survival were measured after different treatments. The number of immune cells and cytokine levels were measured, and the activation of cGAS/STING/IFN-I signaling pathway in DC was evaluated both in vitro and in vivo.

RESULTS

LyOK-432 was more effective than OK-432 in promoting DC maturation and activating the IFN-I pathway. ROD was an injectable hydrogel for effectively loading lyOK-432 and DOX, and presented the controlled-release property. ROD treatment achieved the highest tumor necrosis rate (p < 0.001) and the longest survival time (p < 0.001) compared with the other therapies. The ROD group also displayed the highest percentages of DCs, CD4+ T cells and CD8+ T cells (p < 0.001), the lowest level of Treg cells (p < 0.001), and the highest expression levels of IFN-γ and TNF-α (p < 0.001) compared with the other groups. The expression levels of pSTING, pIRF3, and IFN-β in DCs were obviously higher after treatment of lyOK-432 in combination with DOX than the other therapies. The surviving mice in the ROD group showed a growth inhibition of rechallenged subcutaneous tumor.

CONCLUSION

The novel ROD peptide hydrogel induced an antitumor immunity by activating the STING pathway, which was effective for treating residual liver cancer after iRFA of HCC.

The liver cancer immune microenvironment: Therapeutic implications for hepatocellular carcinoma

The liver is the sixth most common site of primary cancer in humans and the fourth leading cause of cancer-related death in the world. Hepatocellular carcinoma (HCC) accounts for 90% of liver cancers. HCC is a prevalent disease with a progression that is modulated by the immune system. Half of the patients with HCC receive systemic therapies, traditionally sorafenib or lenvatinib, as a first-line therapy. In the last few years, immune-checkpoint inhibitors (ICIs) have revolutionized cancer therapy and have gained an increased interest in the treatment of HCC. In 2020, the combination of atezolizumab (anti-programmed death-ligand 1) and bevacizumab (anti-vascular endothelial growth factor) improved overall survival over sorafenib, resulting in Food and Drug Administration (FDA) approval as a first-line treatment for patients with advanced HCC. Despite these major advances, a better molecular and cellular characterization of the tumor microenvironment is still needed because it has a crucial role in the development and progression of HCC. Inflamed (hot) and noninflamed (cold) HCC tumors and genomic signatures have been associated with response to ICIs. However, there are no additional biomarkers to guide clinical decision-making. Other immune-targeting strategies, such as adoptive T-cell transfer, vaccination, and virotherapy, are currently under development. This review provides an overview on the HCC immune microenvironment, different cellular players, current available immunotherapies, and potential immunotherapy modalities.

New Therapeutics for HCC: Does Tumor Immune Microenvironment Matter?

The incidence of liver cancer is continuously rising where hepatocellular carcinoma (HCC) remains the most common form of liver cancer accounting for approximately 80-90% of the cases. HCC is strongly prejudiced by the tumor microenvironment and being an inflammation-associated condition, the contribution of various immune mechanisms is critical in its development, progression, and metastasis. The tumor immune microenvironment is initially inflammatory which is subsequently replenished by the immunosuppressive cells contributing to tumor immune escape. Regardless of substantial advancement in systemic therapy, HCC has poor prognosis and outcomes attributed to the drug resistance, recurrence, and its metastatic behavior. Therefore, currently, new immunotherapeutic strategies are extensively targeted in preclinical and clinical settings in order to elicit robust HCC-specific immune responses and appear to be quite effective, extending current treatment alternatives. Understanding the complex interplay between the tumor and the immune cells and its microenvironment will provide new insights into designing novel immunotherapeutics to overcome existing treatment hurdles. In this review, we have provided a recent update on immunological mechanisms associated with HCC and discussed potential advancement in immunotherapies for HCC treatment.

Advances in Human Dendritic Cell-Based Immunotherapy Against Gastrointestinal Cancer

Dendritic cells (DCs), the strongest antigen-presenting cells, are a focus for orchestrating the immune system in the fight against cancer. Basic scientific investigations elucidating the cellular biology of the DCs have resulted in new strategies in this fight, including cancer vaccinology, combination therapy, and adoptive cellular therapy. Although immunotherapy is currently becoming an unprecedented bench-to-bedside success, the overall response rate to the current immunotherapy in patients with gastrointestinal (GI) cancers is pretty low. Here, we have carried out a literature search of the studies of DCs in the treatment of GI cancer patients. We provide the advances in DC-based immunotherapy and highlight the clinical trials that indicate the therapeutic efficacies and toxicities related with each vaccine. Moreover, we also offer the yet-to-be-addressed questions about DC-based immunotherapy. This study focuses predominantly on the data derived from human studies to help understand the involvement of DCs in patients with GI cancers.

Efficacy and Safety of Cellular Immunotherapy by Local Infusion for Liver Tumor: A Systematic Review and Meta-Analysis

Background

Cellular immunotherapy has become a new and promising treatment for patients with liver tumor. However, as most immune cells are delivered by intravenous injection, the effect is limited and is likely to produce systemic toxicity. Here, the objective was to investigate the efficacy and safety of cellular immunotherapy by local infusion, which seems to be a promising approach and has not been well-studied.

Methods

The PubMed, Web of Science, Embase, and Cochrane Library databases were searched to obtain literature. The overall response rate (ORR), overall survival (OS) rates, and adverse events were investigated to evaluate the effectiveness and safety of locoregional therapy. The methodological quality of the articles was assessed using the methodological index for non-randomized studies (MINORS) score. The meta-analysis was performed using Stata 15.0.

Results

The eligible 17 studies involved a total of 318 patients. The random-effects model demonstrated that the ORR of local cell infusion therapy was 48% (95% confidence interval [CI]: 26%–70%). The pooled OS rate was 94% (95% CI: 83%–100%) at 6 months, 87% (95% CI: 74%–96%) at 12 months, and 42% (95% CI: 16%–70%) at 24 months. Subgroup analyses suggested that minimally invasive treatment and absence of metastasis were significantly associated with better ORR. Fourteen studies reported a variety of adverse events related to cell therapy by local perfusion. The most common complications after regional infusion of immune cells were myelosuppression (66%), fever (50%), gastrointestinal toxicity (22%), hepatic dysfunction (15%), and pleural effusion and/or ascites (14%).

Conclusions

Immune cell therapy through local perfusion is effective for patients with liver cancer, with manageable toxicity. It demonstrates better prognosis when combined with minimally invasive therapy. Considering the potential limitations, more randomized controlled trials are needed to provide solid evidence for our findings.

The Landscape Of Alpha Fetoprotein In Hepatocellular Carcinoma: Where Are We?

Hepatocellular carcinoma (HCC) is the most common primary liver cancer and has been acknowledged as a leading cause of death among cirrhosis patients. Difficulties in early diagnosis and heterogeneity are obstacles to effective treatment, especially for advanced HCC. Liver transplantation (LT) is considered the best therapy for HCC. Although many biomarkers are being proposed, alpha-fetoprotein (AFP), which was identified over 60 years ago, remains the most utilized. Recently, much hope has been placed in the immunogenicity of AFP to develop novel therapies, such as AFP vaccines and AFP-specific adoptive T-cell transfer (ACT). This review summarizes the performance of AFP as a biomarker for HCC diagnosis and prognosis, as well as its correlation with molecular classes. In addition, the role of AFP in LT is also described. Finally, we highlight the mechanism and application prospects of two immune therapies (AFP vaccine and ACT) for HCC. In general, our review points out the prevalence of AFP in HCC, accompanied by some controversies and novel directions for future research.

Advances in locoregional therapy for hepatocellular carcinoma combined with immunotherapy and targeted therapy

Locoregional therapies (LRTs) of hepatocellular carcinoma (HCC) represented by ablation and TACE has become the main means for the clinical treatment of unresectable HCC. Among these, TACE is used throughout the stage Ib to IIIb of HCC treatment. In recent years, immunotherapy led by immune checkpoint inhibitors has become a hot direction in clinical research. At the same time, targeted drugs such as Sorafenib and Apatinib have played an important role in the treatment and complementary therapy of advanced HCC, and their clinical application has been quite mature. HCC is the sixth most common malignant tumor in the world. When it comes to its treatment, different therapies have different indications, and their individual efficacies are not satisfactory, which makes the exploration of the use of combination therapy in HCC treatment become a new trend. In this paper, the status of the three therapies and the progress of their combined application are briefly reviewed.

Insights into an Immunotherapeutic Approach to Combat Multidrug Resistance in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) has emerged as one of the most lethal cancers worldwide because of its high refractoriness and multi-drug resistance to existing chemotherapies, which leads to poor patient survival. Novel pharmacological strategies to tackle HCC are based on oral multi-kinase inhibitors like sorafenib; however, the clinical use of the drug is restricted due to the limited survival rate and significant side effects, suggesting the existence of a primary or/and acquired drug-resistance mechanism. Because of this hurdle, HCC patients are forced through incomplete therapy. Although multiple approaches have been employed in parallel to overcome multidrug resistance (MDR), the results are varying with insignificant outcomes. In the past decade, cancer immunotherapy has emerged as a breakthrough approach and has played a critical role in HCC treatment. The liver is the main immune organ of the lymphatic system. Researchers utilize immunotherapy because immune evasion is considered a major reason for rapid HCC progression. Moreover, the immune response can be augmented and sustained, thus preventing cancer relapse over the post-treatment period. In this review, we provide detailed insights into the immunotherapeutic approaches to combat MDR by focusing on HCC, together with challenges in clinical translation.

Abscopal Effect of Frozen Autograft Reconstruction Combined with an Immune Checkpoint Inhibitor Analyzed Using a Metastatic Bone Tumor Model

We evaluated the abscopal effect of re-implantation of liquid nitrogen-treated tumor-bearing bone grafts and the synergistic effect of anti-PD-1 (programmed death-1) therapy using a bone metastasis model, created by injecting MMT-060562 cells into the bilateral tibiae of 6-8-week-old female C3H mice. After 2 weeks, the lateral tumors were treated by excision, cryotreatment using liquid nitrogen, excision with anti-PD-1 treatment, and cryotreatment with anti-PD-1 treatment. Anti-mouse PD-1 4H2 was injected on days 1, 6, 12, and 18 post-treatment. The mice were euthanized after 3 weeks; the abscopal effect was evaluated by focusing on growth inhibition of the abscopal tumor. The re-implantation of frozen autografts significantly inhibited the growth of the remaining abscopal tumors. However, a more potent abscopal effect was observed in the anti-PD-1 antibody group. The number of CD8+ T cells infiltrating the abscopal tumor and tumor-specific interferon-γ (IFN-γ)-producing spleen cells increased in the liquid nitrogen-treated group compared with those in the excision group, with no significant difference. The number was significantly higher in the anti-PD-1 antibody-treated group than in the non-treated group. Overall, re-implantation of tumor-bearing frozen autograft has an abscopal effect on abscopal tumor growth, although re-implantation of liquid nitrogen-treated bone grafts did not induce a strong T-cell response or tumor-suppressive effect.

Role of Alpha-Fetoprotein in Hepatocellular Carcinoma Drug Resistance

Hepatocellular carcinoma (HCC) is a major type of primary liver cancer and a major cause of cancer-related deaths worldwide because of its high recurrence rate and poor prognosis. Surgical resection is currently the major treatment measure for patients in the early and middle stages of the disease. Because due to late diagnosis, most patients already miss the opportunity for surgery upon disease confirmation, conservative chemotherapy (drug treatment) remains an important method of comprehensive treatment for patients with middle- and late-stage liver cancer. However, multidrug resistance (MDR) in patients with HCC severely reduces the treatment effect and is an important obstacle to chemotherapeutic success. Alpha-fetoprotein (AFP) is an important biomarker for the diagnosis of HCC. The serum expression levels of AFP in many patients with HCC are increased, and a persistently increased AFP level is a risk factor for HCC progression. Many studies have indicated that AFP functions as an immune suppressor, and AFP can promote malignant transformation during HCC development and might be involved in the process of MDR in patients with liver cancer. This review describes drug resistance mechanisms during HCC drug treatment and reviews the relationship between the mechanism of AFP in HCC development and progression and HCC drug resistance.

Combining cellular immunotherapy was an optional choice for unresectable advanced HCC: A systematic review and meta-analysis

BACKGROUND

The efficacy of cellular immunotherapy in advanced hepatocellular carcinoma (HCC) was controversial. This study was conducted to compare the effectiveness of combining cellular immunotherapy with that of incurable treatment alone.

METHODS

The Ovid Medline, Embase, Cochrane Library and Pubmed were systematically searched due to January 8^th 2020. The keywords include "immunotherapy", "HCC" and study type. Treatment response was evaluated and progression-free survival (PFS) and overall survival (OS) were calculated using hazard ratio (HR) and 95% confidence interval (CI).

RESULTS

A total of 19 studies with 1275 patients were included in the meta-analysis. The median complete response rate (CR) was 19% in combining cellular immunotherapy comparing to 9% in the control group (RR=0.55, P=0.003). No significant difference was found in partial response and stable disease (RR=1.06 and 0.78, P>0.05, respectively). The progression disease rate was higher in the non-cellular immunotherapy group (31%) compared to the cellular immunotherapy group (RR=2.20, P=0.002). Patients treating with cellular immunotherapy had a better OS and PFS compared to those without cellular immunotherapy (HR=0.52 and 0.63, P<0.001). In the subgroup analysis, the only CIK infusion therapy and combined DC with CIK perfusion therapy patients had a better OS (HR=0.52 and 0.49, P<0.001 and P=0.002, respectively).

CONCLUSION

Our results suggested that combining use of cellular immunotherapy in advanced HCC could increase the complete response rate, and thereafter extend the progression-free and overall survival rate. Subgroup analysis suggested that combining use of CIK and DC or using CIK alone could provide the benefit in survival outcome.

Interleukin 15 and Eotaxin correlate with the outcome of breast cancer patients vice versa independent of CTC status

Background

Circulating tumor cells (CTC) in the peripheral blood in women with breast cancer has been found to be an indicator of prognosis before the start of systemic treatment. The aim of this study is the assessment of specific cytokine profiles as markers for CTC involvement that could act as independent prognostic markers in terms of survival outcome for breast cancer patients.

Methods

Patients selected for this study were defined as women with breast cancer of the SUCCESS study. A total of 200 patients’ sera were included in this study, 100 patients being positive for circulating tumor cells (CTC) and 100 patients being CTC negative. The matching criteria were histo-pathological grading, lymph node metastasis, hormone receptor status, TNM classification, and patient survival. Commercial ELISA with a multi cytokine/chemokine array was used to screen the sera for Interleukin 15 (IL-15) and eotaxin.

Results

Statistically significant concentrations were exposed for IL-15 levels regardless of the CTC-Status, lymph node involvement, or hormone receptor status. Significantly enhanced serum IL-15 concentrations were observed in those patients with worse overall survival (OS) and disease-free survival (DFS). Elevated serum concentrations of IL-15 significantly correlate with patients diagnosed with Grade 3 tumor and worse OS. In contrast, patients with a Grade 3 tumor with a favourable OS and DFS demonstrated significantly decreased IL-15 values. The CTC negative patient subgroup with a favourable OS and DFS, showed statistically significant elevated eotaxin values.

Conclusion

These findings suggest a potential functional interaction of increased IL-15 concentrations in the peripheral blood of patients with a worse OS and DFS, regardless of prognostic factors at primary diagnosis. The increased levels of the chemokine eotaxin in CTC negative patients and a favourable OS and DFS, on the other hand, suggest that the overexpression inhibits CTCs entering the peripheral blood, thus emphasizing a significant inhibition of circulation specific metastasis. To sum up, IL-15 could be used as an independent prognostic marker in terms of survival outcome for breast cancer patients and used as an early indicator to highlight high-risk patients and consequently the adjustment of cancer therapy strategies.

Combination Therapy of Pulsed-Wave Ultrasound Hyperthermia and Immunostimulant OK-432 Enhances Systemic Antitumor Immunity for Cancer Treatment

PURPOSE

In this study, we hypothesized that systemic antitumor immunity might be enhanced by combining pulsed-wave ultrasound hyperthermia (pUSHT) with OK-432 and that the induced antitumor immunity could confer protection against tumorigenesis. These hypotheses were tested in bilateral and rechallenged tumor models.

METHODS AND MATERIALS

Bilateral and rechallenged tumor models were applied in the studies. In the bilateral tumor model, BALB/c mice were inoculated in both flanks with CT26-luc tumor cells. The tumors in the right flank were treated with 4 courses of pUSHT with or without OK-432. In the rechallenged tumor model, tumor cells were implanted into the right flank. Once formed, the tumors were treated with pUSHT with OK-432, followed by surgical resection. New tumor cells were then implanted into the contralateral flank. The antitumor response was evaluated via infiltrated immune cells and the severity of necrosis/apoptosis in tumors.

RESULTS

In the bilateral tumor model, the tumor growth rate and growth activity of both treated (100% reduction) and untreated tumors (90.5% reduction) were significantly inhibited with the combination treatment compared with the sham control group, and the systemic antitumor effect was prolonged. The survival rate was significantly enhanced (sham control, 8 days; OK plus pUSHT, >20 days). IFNγ⁺ CD4 (treated tumor, 8.6-fold; untreated tumor, 4-fold), IFNγ⁺ CD8 (treated tumor, 6.7-fold; untreated tumor, 2.6-fold), and T cell and NK cell (treated tumor, 4-fold; untreated tumor, 2.5-fold) infiltration was increased in the combination group compared with the control group. In the rechallenged tumor model, new tumors failed to form with the combination treatment.

CONCLUSION

This experimental study combining pUSHT and OK-432 explored a new therapeutic strategy for controlling colon cancer metastasis. The results show that the combination treatment may produce an effective antitumor immune response.

Safety and Long-Term Outcome of Intratumoral Injection of OK432-Stimulated Dendritic Cells for Hepatocellular Carcinomas After Radiofrequency Ablation

Dendritic cell (DC)–based immunotherapies are believed to help eradicate residual tumor cells, including hepatocellular carcinoma (HCC). Here, we assessed the safety and clinical response to OK432-stimulated monocyte-derived DCs (MoDCs) in treating HCC after radiofrequency ablation (RFA). MoDCs were derived from 30 HCC patients in the presence of interleukin-4 and granulocyte-macrophage colony stimulating factor for 5 days and then cultured for 2 more days in the medium (basic protocol) or stimulated with OK432. On day 7, DCs were harvested and percutaneously injected into HCC tumors after RFA. We observed no grade 3 or 4 National Cancer Institute Common Toxicity Criteria adverse events. Kaplan-Meier analysis indicated that patients treated with RFA + OK432-stimulated DCs transfer had longer recurrence-free survival than those treated with RFA + basic-protocol DCs (median: 24.8 vs 13.0 months; P = .003). RFA with DC infusion can enhance various tumor-associated antigen (TAA)–specific T-cell responses. Additionally, the 5-year RFS rate for patients with significantly increased TAA-specific T-cell responses was much higher than for other patients (50.0% vs. 7.7%; P = .030). Our study provides useful information for development of HCC immunotherapies (trial registration: UMIN000001701).

Liver Tumor Microenvironment

The tumor microenvironment (TME) has recently been recognized as an important part of tumor development and growth. TME is a dynamic system orchestrated by immune, cancer and inflammatory cells, as well as the stromal tissue and surrounding extracellular matrix. While TME of primary hepatic tumors is usually characterized by a strong inflammatory background, the TME of liver metastases typically consists of otherwise healthy liver tissue. Chronic inflammation and hypoxia are key to the development and progression of primary liver cancer. The injury caused by chronic inflammation creates a condition of immune evasion that initiates a cascade of events that eventually leads to liver carcinogenesis.With liver metastases, primary tumors "prime" the target organs via secreting factors that induce expansion of myeloid cell populations and create a solid ground for successful cancer settlement. Once in the liver, metastatic cells begin a neovascularization process that is driven mainly by VEGF and FGF. Due to high mortality rates associated with liver cancer, as well as the limited effective treatment options for advanced disease, new therapies are urgently needed. Targeting a single molecule in a number of interactions between the tumor and the TME is highly unlikely to reduce tumor growth. Future trials should focus on combination therapies (i.e. targeted therapies combined with immunotherapy) to treat liver malignancies efficiently.

Ablation plus Transarterial Embolic Therapy for Hepatocellular Carcinoma Larger than 3 cm: Science, Evidence, and Future Directions

Thermal ablation is widely regarded as definitive therapy for early-stage hepatocellular carcinoma, but its efficacy decreases in tumors greater than 3 cm. Extensive clinical studies have supported improved outcomes provided through combining transarterial embolic therapy with ablation in the treatment of larger tumors. This article will provide a survey of the science and data for combination therapy in both thermal and nonthermal ablation modalities, as well as describe emerging applications.

Immunotherapy with dendritic cells and cytokine-induced killer cells for hepatocellular carcinoma: A meta-analysis

BACKGROUND

Hepatocellular carcinoma (HCC) has been revealed as the second most common cause of cancer-related deaths worldwide. The introduction of cell-based immunotherapy, including dendritic cells (DCs) and cytokine-induced killer cells (CIKs), has brought HCC patients an effective benefit. However, the efficacy and necessity of cellular immunotherapy after different interventional therapy remains to be further explored.

AIM

To investigate the efficacy of cellular immunotherapy, involving DCs and CIKs, combined with different conventional treatments of HCC.

METHODS

We performed a literature search on PubMed and Web of Science up to February 15, 2019. Long-term efficacy (overall survival and recurrence) and short-term adverse effects were investigated to assess the effectiveness of immunotherapy with DCs and/or CIKs. Review Manager 5.3 was used to perform the analysis.

RESULTS

A total of 22 studies involving 3756 patients selected by eligibility inclusion criteria were forwarded for meta-analysis. Combined with the conventional clinical treatment, immunotherapy with DCs and/or CIKs was demonstrated to significantly improve overall survival at 6 mo [risk ratio (RR) = 1.07; 95% confidence interval (CI): 1.01-1.13, P = 0.02], 1 year (RR = 1.12; 95%CI: 1.07-1.17, P < 0.00001), 3 years (RR = 1.23; 95%CI: 1.15-1.31, P < 0.00001) and 5 years (RR = 1.26; 95%CI: 1.15-1.37, P < 0.00001). Recurrence rate was significantly reduced by cellular immunotherapy at 6 mo (RR = 0.50; 95%CI: 0.36-0.69, P < 0.0001) and 1 year (RR = 0.82; 95%CI: 0.75-0.89, P < 0.00001). Adverse effect assessment addressed that immunotherapy with DCs and/or CIKs was accepted as a safe, feasible treatment.

CONCLUSION

Combination immunotherapy with DCs, CIKs and DC/CIK with various routine treatments for HCC was evidently suggested to improve patients' prognosis by increasing overall survival and reducing cancer recurrence.

Immune cell therapy for hepatocellular carcinoma

Given the success of immune checkpoint inhibitors and chimeric antigen receptor (CAR) T cells in clinical settings, the host immune system plays an important role in the recognition and targeting of tumor cells in cancer immunotherapy. As a result, there have been numerous advancements in immune cell therapy using human immune cells. However, recent evidence suggests that one type of immunotherapy alone is not effective for the treatment of cancer, particularly solid tumors. Thus, effective immunotherapy combinations, such as the combination of checkpoint inhibitors and immune cell therapy, are needed. This review focuses on hepatocellular carcinoma among other solid tumors and discusses the current status and future of immune cell therapy in cancer immunotherapy.

Immunotherapy and the Interventional Oncologist: Challenges and Opportunities-A Society of Interventional Oncology White Paper

Interventional oncology is a subspecialty field of interventional radiology that addresses the diagnosis and treatment of cancer and cancer-related problems by using targeted minimally invasive procedures performed with image guidance. Immuno-oncology is an innovative area of cancer research and practice that seeks to help the patient's own immune system fight cancer. Both interventional oncology and immuno-oncology can potentially play a pivotal role in cancer management plans when used alongside medical, surgical, and radiation oncology in the care of cancer patients.

Effect of dendritic cell-based immunotherapy on hepatocellular carcinoma: A systematic review and meta-analysis

BACKGROUND AIMS

Dendritic cell (DC)-based immunotherapy has recently been reported frequently in the treatment of hepatocellular carcinoma (HCC); however, its efficacy remains controversial. In this study, we aimed to evaluate the clinical efficacy of DC-based immunotherapy on HCC by conducting a systematic review and meta-analysis.

METHODS

PubMed, Cochrane Library, Embase and Web of Science were searched to identify clinical trials on DC-based immunotherapy for HCC published up to January 31, 2018. The articles were selected according to pre-established inclusion criteria and methodologic quality, and publication bias were evaluated.

RESULTS

A total of 1276 cases from 19 clinical trials were included. Compared with traditional treatment, further DC-based therapy enhanced the CD4⁺ T/CD8⁺ T ratio (standardized mean difference: 0.68, 95% confidence interval [CI] 0.46-0.89, P < 0.001); increased the 1-year, 18-month and 5-year progression-free survival (PFS) rate and the 1-year, 18-month and 2-year overall survival (OS) rate (relative risk > 1, P < 0.05), prolonged the median PFS time (median survival ratio [MSR]: 1.98, 95% CI: 1.60-2.46, P < 0.001) and median OS time (MSR: 1.72, 95% CI: 1.51-1.96, P < 0.001). Adverse reactions were mild.

CONCLUSIONS

DC-based therapy not only enhanced anti-tumor immunity, improved the survival rate and prolonged the survival time of HCC patients, but it was also safe. These findings will provide encouraging information for further development of DC-based immunotherapy as an adjuvant treatment for HCC. However, the results must be interpreted with caution because of the small study numbers, publication bias and the various of study designs, pre-treatment and therapeutic processes of DCs.

Emergence of immunotherapy as a novel way to treat hepatocellular carcinoma

Tumor immunity proceeds through multiple processes, which consist of antigen presentation by antigen presenting cells (APCs) to educate effector cells and destruction by the effector cytotoxic cells. However, tumor immunity is frequently repressed at tumor sites. Malignantly transformed cells rarely survive the attack by the immune system, but cells that do survive change their phenotypes to reduce their immunogenicity. The resultant cells evade the attack by the immune system and form clinically discernible tumors. Tumor microenvironments simultaneously contain a wide variety of immune suppressive molecules and cells to dampen tumor immunity. Moreover, the liver microenvironment exhibits immune tolerance to reduce aberrant immune responses to massively-exposed antigens via the portal vein, and immune dysfunction is frequently associated with liver cirrhosis, which is widespread in hepatocellular carcinoma (HCC) patients. Immune therapy aims to reduce tumor burden, but it is also expected to prevent non-cancerous liver lesions from progressing to HCC, because HCC develops or recurs from non-cancerous liver lesions with chronic inflammatory states and/or cirrhosis and these lesions cannot be cured and/or eradicated by local and/or systemic therapies. Nevertheless, cancer immune therapy should augment specific tumor immunity by using two distinct measures: enhancing the effector cell functions such as antigen presentation capacity of APCs and tumor cell killing capacity of cytotoxic cells, and reactivating the immune system in immune-suppressive tumor microenvironments. Here, we will summarize the current status and discuss the future perspective on immune therapy for HCC.

Alpha-Fetoprotein and Hepatocellular Carcinoma Immunity

Hepatocarcinoma is one of the most prevalent gastroenterological cancers in the world with less effective therapy. As an oncofetal antigen and diagnostic marker for liver cancer, alpha-fetoprotein (AFP) possesses a variety of biological functions. Except for its diagnosis in liver cancer, AFP has become a target for liver cancer immunotherapy. Although the immunogenicity of AFP is weak and it could induce the immune escapes through inhibiting the function of dendritic cells, natural killer cells, and T lymphocytes, AFP has attracted more attention in liver cancer immunotherapy. By in vitro modification, the immunogenicity and immune response of AFP could be enhanced. AFP-modified immune cell vaccine or peptide vaccine has displayed the specific antitumor immunity against AFP-positive tumor cells and laid a better foundation for the immunotherapy of liver cancer.

Association Between High-Avidity T-Cell Receptors, Induced by α-Fetoprotein-Derived Peptides, and Anti-Tumor Effects in Patients With Hepatocellular Carcinoma

BACKGROUND & AIMS

Levels of α-fetoprotein (AFP) are measured for surveillance and diagnosis of hepatocellular carcinoma (HCC). We performed a phase 1 trial to evaluate the safety and efficacy of AFP-derived peptides as an anti-tumor vaccine for patients with advanced HCC, and characterized induction of AFP-specific T-cell receptors (TCRs).

METHODS

We performed a prospective study of 15 patients with HCC seen at Kanazawa University Hospital in Japan from March 2010 through March 2012. Each patient was given a subcutaneous injection of 3 mg AFP-derived peptides (AFP₃₅₇ and AFP₄₀₃) in an emulsion with incomplete Freund's adjuvant every other week for at least 6 weeks. Patients were evaluated every 8 weeks by radiologic imaging; adverse events and toxicities were categorized and graded using the common terminology criteria for adverse events. Criteria for discontinuation included unacceptable toxicities and disease progression defined as progressive disease using the Response Evaluation Criteria In Solid Tumors criteria. Patients' immune responses were monitored using an interferon-gamma enzyme-linked immunospot assay. Peptide-specific TCRs were assessed using a rapid TCR cloning and evaluation system. The observation period was 730 days. A complete response was defined as the disappearance of all tumors; stable disease was defined as tumors whose total diameter remained between >70% and <120% of the baseline measurement, without new lesions.

RESULTS

We did not observe any serious adverse reactions to the peptides, which were well tolerated. Of the 15 patients who received at least 3 injections, 5 (33%) had an immune response to the peptides. One of the 15 patients had a complete response and disease stabilized in 8 patients. In 4 of the 15 patients, we detected AFP₃₅₇-specific CD8 T cells; we cloned 14 different TCRs with different avidities for the peptide. A TCR with the highest avidity was observed in the patient who achieved a complete response for more than 2 years.

CONCLUSIONS

In a phase 1 trial, administration of AFP-derived peptides to 15 patients with HCC did not cause adverse events and produced T cells with receptors that reacted to the peptides; 1 patient had a complete response and tumor growth slowed in 8 patients. T cells from the patient with a complete response expressed a highly functional TCR induced by the peptide vaccines. UMIN-CTR no: UMIN000003514.

Effects of programmed death-ligand 1 expression on OK-432 immunotherapy following transurethral resection in non-muscle invasive bladder cancer

The present study aimed to investigate the effect of the negative costimulatory molecule programmed death-ligand 1 (PD-L1) on immunotherapy with OK-432, following transurethral resection of bladder tumors in non-muscle invasive bladder cancer (NMIBC), and to elucidate the underlying mechanism. PD-L1 was detected by immunohistochemical staining in tumor specimens from 55 cases of NMIBC following postoperative immunotherapy with OK-432. The PD-L1 mRNA and protein expression levels were measured in the bladder cancer T24 cell line and the human uroepithelial SV-HUC-1 cell line, following treatment with interleukin (IL)-2, interferon (IFN)-α and IFN-γ, by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot analysis, respectively. PD-L1 was widely expressed in the NMIBC tumors, with 56.4% (31/55) of specimens exhibiting positive staining. When compared with PD-L1-negative patients, PD-L1-positive patients exhibited significantly increased recurrence [48.4% (15/31) vs. 16.7% (4/24)] and progression [16.1% (5/31) vs. 4.2% (1/24)] rates (P<0.05). RT-qPCR and western blotting demonstrated that cytokines IL-2, IFN-α and IFN-γ markedly upregulated PD-L1 mRNA expression rates and protein levels in bladder cancer T24 cells (P<0.05), but had no significant effect in non-tumor SV-HUC-1 cells. In conclusion, PD-L1 expression was negatively-associated with the efficacy of OK-432 intravesical immunotherapy in patients with NMIBC. The results indicated that the involved mechanism occurred via upregulation of PD-L1 by immune cytokines, which in turn suppressed the antitumor effectiveness of the immune system, thereby promoting tumor recurrence and progression.

Promising new strategies for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common causes of cancer death worldwide. It usually arises based on a background of chronic liver diseases, defined as the hypercarcinogenic state. The current treatment options for HCC ranging from locoregional treatments to chemotherapies, including sorafenib, effectively regulate the limited sizes and numbers of the nodules. However, these treatments remain unsatisfactory because they have insufficient antitumor effects on the large and numerous nodules associated with HCC and because of a high recurrence rate in the surrounding inflamed liver. To develop novel and promising therapies with higher antitumor effects, recent progress in identifying molecular targets and developing immunological procedures for HCC are reviewed. The molecular targets discussed include the intracellular signaling pathways of protein kinase B/mammalian target of rapamycin and RAS/RAF/mitogen-activated protein kinase, Wnt/β-catenin and glutamine synthetase, insulin-like growth factor, signal transducer and activator of transcription 3, nuclear factor-κB and telomerase reverse transcriptase, and c-MET. Immunological studies have focused mainly on target identification, T cells, natural killer cells, dendritic cells, natural killer T cells, and vaccine development.

Phase 1/2 study of immunotherapy with dendritic cells pulsed with autologous tumor lysate in patients with refractory bone and soft tissue sarcoma

BACKGROUND

There are limited options for the curative treatment of refractory bone and soft tissue sarcomas. The purpose of this phase 1/2 study was to assess the immunological and clinical effects of dendritic cells (DCs) pulsed with autologous tumor lysate (TL) in patients with advanced bone and soft tissue sarcomas.

METHODS

Thirty-seven patients with metastatic or recurrent sarcomas were enrolled in this study. Peripheral blood mononuclear cells obtained from the patients were suspended in media containing interleukin 4 (IL-4) and granulocyte-macrophage colony-stimulating factor. Subsequently, these cells were treated with TL, tumor necrosis factor α, and OK-432. The DCs were injected into the inguinal or axillary region. One treatment course comprised 6 weekly DC injections. The toxicity, clinical response (tumor volume, serum interferon-γ [IFN-γ], and serum IL-12), and oncological outcomes were observed.

RESULTS

In total, 47 courses of DC therapy were performed in 37 patients. No severe adverse events or deaths associated with the DC injections were observed in the study patients. Increased serum IFN-γ and IL-12 levels were observed 1 month after the DC injection. Among the 37 patients, 35 patients were assessed for clinical responses: 28 patients showed tumor progression, 6 patients had stable disease, and 1 patient showed a partial response 8 weeks after the DC injection. The 3-year overall and progression-free survival rates of the patients were 42.3% and 2.9%, respectively.

CONCLUSIONS

Although DC therapy appears safe and resulted in an immunological response in patients with refractory sarcoma, it resulted in an improvement of the clinical outcome in only a small number of patients. Cancer 2017;123:1576-1584. © 2017 American Cancer Society.

Tumor regulation of the tissue environment in the liver

The tumor microenvironment (TME) in the liver plays an important role in primary and metastatic liver tumor formation and tumor growth promotion. Cellular and non-cellular components of the TME significantly influence tumor development, growth, metastatic spread, anti-tumor immunity and response to tumor therapy. The cellular components of the TME in the liver not only consist of infiltrating immune cells, but also of liver-resident cells such as liver sinusoidal endothelial cells (LSEC) and hepatic stellate cells (HSC), which promote tumor growth by negatively regulating tumor-associated immune responses. In this review, we characterize cells of the TME with pro- and anti-tumor function in primary and metastatic liver tumors. Furthermore, we summarize mechanisms that permit growth of hepatic tumors despite the occurrence of spontaneous anti-tumor immune responses and how novel therapeutic approaches targeting the TME could unleash tumor-specific immune responses to improve survival of liver cancer patients.

Systematic evaluation of circulating inflammatory markers for hepatocellular carcinoma

BACKGROUNDS & AIMS

A number of circulating inflammatory factors are implicated in the pathogenesis and prognostication of hepatocellular carcinoma (HCC). We aim to evaluate the prognostication of multiple serum inflammatory factors simultaneously and develop an objective inflammatory score for HCC.

METHODS

A prospective cohort of 555 patients with HCC with paired serum samples was accrued from 2009 to 2012. The blood levels of conventional inflammatory markers, namely C-reactive protein (CRP), albumin, neutrophils, lymphocytes and platelet, were determined, and 41 other exploratory markers were measured by a multiplex assay. The prognostication and interaction of markers were determined by univariate and multivarite analyses.

RESULTS

The cohort was randomly divided into training cohort (n=139) and validation cohort (n=416). There were no differences in baseline characteristics between the two cohorts. In the training cohort, independent prognostic factors for overall survival included CRP (hazard ratio [HR] 1.107; P=.003), albumin (HR 0.953; P=.032) and interleukin-8 (HR=5.816; P<.001). We have modified the existing inflammation-based index (IBI) by adding serum interleukin-8 level. The modified IBI could stratify patients into four groups with distinct overall survival (P<.001). The results were also validated in the validation cohort. When compared with IBI and other conventional inflammatory markers, the modified IBI had better prognostic performance with higher c-index and homogeneity likelihood ratio chi-square.

CONCLUSIONS

Among the conventional and exploratory circulating inflammatory markers, higher CRP, lower albumin and higher interleukin-8 were independent prognosticators. By combining these factors, a simple and accurate inflammatory index could be constructed.

Additive antitumour response to the rabbit VX2 hepatoma by combined radio frequency ablation and toll like receptor 9 stimulation

INTRODUCTION

Radiofrequency ablation (RFA), a palliative therapeutic option for solid hepatic tumours, stimulates localised and systemic antitumour cytotoxic T cells. We studied how far addition of CpG B oligonucleotides, toll like receptor (TLR) 9 agonists, would increase the antitumoural T cell response of RFA in the highly aggressive VX2 hepatoma.

METHODS

Rabbits were randomised to receive RFA, CpG B, their combination or no therapy. The antitumour efficacy of RFA alone or in combination with CpG B was further tested by rechallenging a separate group with intravenously injected VX2 tumour cells after 120 days. Animals were assessed for survival, tumour size and spread, and tumour and immune related histological markers after 120 days. Peripheral blood mononuclear cells were tested for tumour-specific T cell activation and cytotoxicity. Immune modulatory cytokines tumour necrosis factor α, interleukin (IL)-2/IL-8/IL-10/IL-12 and interferon γ, and vascular endothelial growth factor were measured in serum.

RESULTS

Mean survival of untreated animals was 36 days, as compared with 97, 78 and 114 days for RFA, CpG and combination therapy, respectively. Compared with untreated controls, antitumour T cell stimulation/cytotoxicity increased 26/16-fold, 32/17-fold and 50/38-fold 2 weeks after RFA, CpG and combination treatments, respectively. The combination inhibited tumour spread to lungs and peritoneum significantly and prohibited new tumour growth in animals receiving a secondary systemic tumour cell injection. RFA alone induced a Th1 cytokine pattern, while IL-8 and IL-10 were only upregulated in CpG treated animals and controls.

CONCLUSIONS

The combination of TLR9 stimulation with RFA resulted in a potentiated antitumour T cell response and cytotoxicity in the VX2 tumour model. Only this combination prevented subsequent tumour spread and resulted in a significantly improved survival, justifying the need for further exploration of the combination of ablative therapies and TLR9 agonists in liver cancer.

Potentiality of immunotherapy against hepatocellular carcinoma

Hepatocellular carcinoma (HCC), the predominant form of primary liver cancer, is the fifth most common cancer worldwide and the second leading cause of cancer-related death. Despite the high incidence, treatment options remain limited for advanced HCC, and as a result prognosis continues to be poor. Current therapeutic options, surgery, chemotherapy and radiotherapy, have only modest efficacy. New treatment modalities to prolong survival and to minimize the risk of adverse response are desperately needed for patients with advanced HCC. Tumor immunotherapy is a promising, novel treatment strategy that may lead to improvements in both treatment-associated toxicity and outcome. The strategies have developed in part through genomic studies that have yielded candidate target molecules and in part through basic biology studies that have defined the pathways and cell types regulating immune response. Here, we summarize the various types of HCC immunotherapy and argue that the newfound field of HCC immunotherapy might provide critical advantages in the effort to improve prognosis of patients with advanced HCC. Already several immunotherapies, such as tumor-associated antigen therapy, immune checkpoint inhibitors and cell transfer immunotherapy, have demonstrated safety and feasibility in HCC patients. Unfortunately, immunotherapy currently has low efficacy in advanced stage HCC patients; overcoming this challenge will place immunotherapy at the forefront of HCC treatment, possibly in the near future.

Serum levels of chemokines CCL4 and CCL5 in cirrhotic patients indicate the presence of hepatocellular carcinoma

BACKGROUND

Most hepatocellular carcinomas (HCCs) are diagnosed at an advanced stage. The prognostic value of serum tumour markers alpha-fetoprotein (AFP) and des-gamma-carboxy prothrombin (DCP) is limited. The aim of our study is to evaluate the diagnostic value of serum growth factors, apoptotic and inflammatory mediators of cirrhotic patients with and without HCC.

METHODS

Serum samples were collected from cirrhotic potential liver transplant patients (LTx) with (n=61) and without HCC (n=78) as well as from healthy controls (HCs; n=39). Serum concentrations of CRP, neopterin and IL-6 as markers of inflammation and thrombopoietin (TPO), GCSF, FGF basic and VEGF, HMGB1, CK-18 (M65) and CK18 fragment (M30) and a panel of proinflammatory chemokines (CCL2, CCL3, CCL4, CCL5, CXCL5 and IL-8) were measured. Chi square, Fisher exact, Mann-Whitney U-tests, ROC curve analysis and forward stepwise logistic regression analyses were applied.

RESULTS

Patients with HCC had higher serum TPO and chemokines (P<0.001 for TPO, CCL4, CCL5 and CXCL5) and lower CCL2 (P=0.008) levels than cirrhotic patients without HCC. Multivariate forward stepwise regression analysis for significant parameters showed that among the studied parameters CCL4 and CCL5 (P=0.001) are diagnostic markers of HCC. Serum levels of TPO and chemokines were lower, whereas M30 was significantly higher in cirrhotic patients than in HCs.

CONCLUSIONS

High serum levels of inflammatory chemokines such as CCL4 and CCL5 in the serum of cirrhotic patients indicate the presence of HCC.

Current concepts of immune based treatments for patients with HCC: from basic science to novel treatment approaches

The recent approval of two immune checkpoint inhibitors for the treatment of malignant melanoma has sparked great interest by physicians and basic scientists searching for novel therapeutics for GI cancer. Chronic inflammation is recognised as a major risk factor for the development of hepatocellular carcinoma (HCC) and makes this type of cancer a potentially ideal target for an immune based treatment approach. Further evidence for a critical role of immune responses in patients with HCC is derived from the fact that immune signatures and profiles predict patients' outcome as well as the fact that tumour-induced spontaneous antitumour immunity can be detected. In addition ablative therapies can lead to changes in the number, phenotype and function of different immune cell subsets, which correlate with patients' survival. Various HCC-specific mouse models have been developed, which improve our understanding of hepatocarcinogenesis and tumour-immune cell interactions, and lead to the development of novel immune based treatment approaches, which are currently being evaluated in preclinical and in early clinical settings. Immune checkpoint blockade along with adoptive immune cell therapy and vaccine approaches are currently being evaluated either alone or in combination with other treatments. Here, we provide an overview for the rationale of immunotherapy in HCC, summarise ongoing studies and provide a perspective for immune based approaches in patients with HCC.

Transcatheter embolization therapy in liver cancer: an update of clinical evidences

Transarterial chemoembolization (TACE) is a form of intra-arterial catheter-based chemotherapy that selectively delivers high doses of cytotoxic drug to the tumor bed combining with the effect of ischemic necrosis induced by arterial embolization. Chemoembolization and radioembolization are at the core of the treatment of liver hepatocellular carcinoma (HCC) patients who cannot receive potentially curative therapies such as transplantation, resection or percutaneous ablation. TACE for liver cancer has been proven to be useful in local tumor control, to prevent tumor progression, prolong patients' life and control patient symptoms. Recent evidence showed in patients with single-nodule HCC of 3 cm or smaller without vascular invasion, the 5-year overall survival (OS) with TACE was similar to that with hepatic resection and radiofrequency ablation. Although being used for decades, Lipiodol(®) (Lipiodol(®) Ultra Fluid(®), Guerbet, France) remains important as a tumor-seeking and radio-opaque drug delivery vector in interventional oncology. There have been efforts to improve the delivery of chemotherapeutic agents to tumors. Drug-eluting bead (DEB) is a relatively novel drug delivery embolization system which allows for fixed dosing and the ability to release the anticancer agents in a sustained manner. Three DEBs are available, i.e., Tandem(®) (CeloNova Biosciences Inc., USA), DC-Beads(®) (BTG, UK) and HepaSphere(®) (BioSphere Medical, Inc., USA). Transarterial radioembolization (TARE) technique has been developed, and proven to be efficient and safe in advanced liver cancers and those with vascular complications. Two types of radioembolization microspheres are available i.e., SIR-Spheres(®) (Sirtex Medical Limited, Australia) and TheraSphere(®) (BTG, UK). This review describes the basic procedure of TACE, properties and efficacy of some chemoembolization systems and radioembolization agents which are commercially available and/or currently under clinical evaluation. The key clinical trials of transcatheter arterial therapy for liver cancer are summarized.

Monocyte-derived dendritic cells from cirrhotic patients retain similar capacity for maturation/activation and antigen presentation as those from healthy subjects

Few studies have investigated the impact of liver cirrhosis on dendritic cell function. The purpose of this study was to compare the activation and antigen-presentation capacity of monocyte-derived dendritic cells (MoDC) from cirrhotic patients (CIR) relative to healthy donors (HD). MoDC from CIR and HD were matured, phenotyped, irradiated and pulsed with 15mer peptides for two hepatocellular carcinoma-related antigens, alphafetoprotein and glypican-3, then co-cultured with autologous T-cells. Expanded T-cells were evaluated by interferon-gamma ELISPOT and intracellular staining. 15 CIR and 7 HD were studied. While CD14+ monocytes from CIR displayed enhanced M2 polarization, under MoDC-polarizing conditions, we identified no significant difference between HD and CIR in maturation-induced upregulation of co-stimulation markers. Furthermore, no significant differences were observed between CIR and HD in subsequent expansion of tumor antigen-specific IFNγ+ T-cells.

CONCLUSION

MoDCs isolated from cirrhotic individuals retain similar capacity for in vitro activation, maturation and antigen-presentation as those from healthy donors.

Serum IL-9, IL-17, and TGF-β levels in subjects with diabetic kidney disease (CURES-134)

The role of inflammation in both diabetes and diabetic kidney disease (DKD) is becoming more widely accepted. However, the role of recently characterized T cell cytokines interleukin (IL)-9 and IL-17 in diabetes and especially DKD is less well studied. Transforming growth factor beta (TGF-β) controls the secretion of both of these cytokines. In this study, we estimated the levels of IL-9, IL-17, and TGF-β in the serum of subjects with normal glucose tolerance (NGT = 88) and subjects with type 2 diabetes without (diabetes mellitus (DM) = 65) and with DKD (DKD = 97) using enzyme-linked immunosorbent assay (ELISA), and we correlated these levels with the clinical risk factors of diabetes and DKD. IL-17 levels showed a serial decline and TGF-β levels showed a serial increase from NGT to DM to DKD (p < 0.001). However, the IL-9 levels were significantly reduced in the DM group compared to the NGT and DKD group (p < 0.001). While TGF-β and IL-17 showed a positive and negative correlation, respectively, with fasting and postprandial glucose levels and glycated hemoglobin (HbA1c), IL-9 showed positive correlation with urea and microalbuminuria. Apart from pro-inflammatory cytokines, T helper (Th) cytokines might play an important role in insulin resistance and DKD.

Combination radiofrequency ablation and local injection of the immunostimulant bacillus Calmette-Guérin induces antitumor immunity in the lung and at a distant VX2 tumor in a rabbit model

PURPOSE

To evaluate whether the combination of radiofrequency (RF) ablation and local injection of the immunostimulant Mycobacterium bovis bacillus Calmette-Guérin (BCG) induces systemic antitumor immunity.

MATERIALS AND METHODS

Japanese White rabbits with lung and auricle VX2 tumors were randomized into three groups: control (n = 8; no treatment), RF ablation only (n = 8; RF ablation to the lung tumor), and RF ablation with local BCG injection into the lung tumor (n = 8). Treatments were performed 1 week after tumor implantation. Survival was evaluated with Kaplan-Meier method and log-rank test. Weekly mean volume and specific growth rate (SGR) of auricle tumors were calculated, and comparisons were made by Mann-Whitney test.

RESULTS

Median survival of control, RF-only, and RF/BCG groups were 23, 41.5, and 103.5 days, respectively. Survival was significantly prolonged in the RF-only and RF/BCG groups compared with the control group (P = .034 and P =.003, respectively), but no significant difference was found between the RF-only and RF/BCG groups (P = .279). Only in the RF/BCG group was mean auricle tumor volume decreased 5 weeks after implantation. No significant difference in SGR was found between the control and RF-only groups (P = .959), but SGR in the RF/BCG group was significantly lower than in the control group (P = .005).

CONCLUSIONS

The combination of RF ablation and local injection of BCG resulted in distant tumor suppression compared with the control group, whereas RF ablation alone did not produce this effect. Therefore, the combination of RF ablation and local injection of BCG may induce systemic antitumor immunity.

Efficient generation of highly immunocompetent dendritic cells from peripheral blood of patients with hepatitis C virus-related hepatocellular carcinoma

BACKGROUND & AIMS

Immunotherapy using dendritic cells (DCs) is a promising cancer therapy. The success of this therapy depends on the function of induced DCs. However, there has been no consensus on optimal conditions for DC preparation in vitro for immunotherapy of hepatocellular carcinoma (HCC) patients. To address relevant issues, we evaluated the procedures to induce DCs that efficiently function in hepatitis C virus (HCV)-related HCC.

METHODS

We studied immunological data from 14 HCC patients. The DC preparation and the surface markers were assessed by flow cytometric analysis. Four different additional activation stimuli (Method I, medium alone; Method II, with OK-432; Method III, with IL-1β+IL-6+TNF-α; Method IV, with IL-1β+IL-6+TNF-α+PGE2) were tested and the functions of DCs were confirmed by examination of the ability of phagocytosis, cytokine production and allogeneic mixed lymphocyte reaction (MLR).

RESULTS

The numbers of DCs induced and their cytokine production ability were not different between healthy controls and HCC patients. T-cell stimulatory activity of DCs in MLR was significantly lower in HCC patients than in healthy controls. The maturation of DCs with OK-432 boosted production of cytokines and chemokines, such as IL-2, IL-12p70, IFN-γ, TNF-α, IL-13 and MIP1α, and restored T-cell stimulatory activity of DCs in MLR.

CONCLUSIONS

The clinically approved compound OK-432 is a candidate for highly immunocompetent DC preparation and may be considered as a key drug for immunotherapy of HCV-related HCC patients.

Study progress in immune escape mechanism and immunotherapy for primary hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a common malignant tumor as well as a big threat to human health. The occurrence, development and prognosis of HCC are closely relevant to the immune escape and immune function in HCC patients. HCC patients, especially those in the terminal stage of the disease, have impaired immune function, which leads to reduced quality of life and raised death rate. Since immunotherapy can regulate the immune function to reduce recurrence and metastasis, improve the life quality and prolong survival, it has become an important part of comprehensive treatment for HCC. In this paper, we review the latest progress in research of immune escape mechanism and immunotherapy for primary HCC.

In vivo immunological antitumor effect of OK-432-stimulated dendritic cell transfer after radiofrequency ablation

Radiofrequency ablation therapy (RFA) is a radical treatment for liver cancers and induces tumor antigen-specific immune responses. In the present study, we examined the antitumor effects of focal OK-432-stimulated dendritic cell (DC) transfer combined with RFA and analyzed the functional mechanisms involved using a murine model. C57BL/6 mice were injected subcutaneously with colon cancer cells (MC38) in their bilateral flanks. After the establishment of tumors, the subcutaneous tumor on one flank was treated using RFA, and then OK-432-stimulated DCs were injected locally. The antitumor effect of the treatment was evaluated by measuring the size of the tumor on the opposite flank, and the immunological responses were assessed using tumor-infiltrating lymphocytes, splenocytes and draining lymph nodes. Tumor growth was strongly inhibited in mice that exhibited efficient DC migration after RFA and OK-432-stimulated DC transfer, as compared to mice treated with RFA alone or treatment involving immature DC transfer. We also demonstrated that the antitumor effect of this treatment depended on both CD8-positive and CD4-positive cells. On the basis of our findings, we believe that combination therapy for metastatic liver cancer consisting of OK-432-stimulated DCs in combination with RFA can proceed to clinical trials, and it is anticipated to be markedly superior to RFA single therapy.

The dark side of dendritic cells: development and exploitation of tolerogenic activity that favor tumor outgrowth and immune escape

Dendritic cells (DC) play a central role in the regulation of the immune responses by providing the information needed to decide between tolerance, ignorance, or active responses. For this reason different therapies aim at manipulating DC to obtain the desired response, such as enhanced cell-mediated toxicity against tumor and infected cells or the induction of tolerance in autoimmunity and transplantation. In the last decade studies performed in these settings have started to identify (some) molecules/factors involved in the acquisition of a tolerogenic DC phenotype as well as the underlying mechanisms of their regulatory function on different immune cell populations.

Gendicine in interventional chemotherapy of primary hepatocarcinoma

AIM: To prospectively evaluate the value of Gendicine (recombinant human adenovirus p53 injection) in interventional chemotherapy of primary hepatocarcinoma.

METHODS: A total of 162 patients with primary hepatocarcinoma who were treated from January 2008 to December 2010 at Shanghai Changhai Hospital and the 113rd Hospital of PLA were recruited in the study. They were randomly divided into three groups: an intratumoral injection group, a hepatic artery perfusion group, and a control group. The intratumoral injection group (n = 56) underwent intratumoral injection of Gendicine plus hepatic arterial infusion chemotherapy. The hepatic artery perfusion group (n = 62) underwent hepatic artery perfusion of Gendicine and hepatic arterial infusion chemotherapy. The control group (n = 44) underwent simple hepatic arterial infusion chemotherapy. Follow-up period was 24 mo. The efficacy and adverse reactions were observed.

RESULTS: The short-term effects were assessed at one month. In the intratumoral injection group, complete remission was achieved in 6 cases, partial remission in 42 cases, stable disease in 5 cases, and progressive disease in 3 cases. The corresponding figures in hepatic artery perfusion group were 7, 42, 8 and 5, and 1, 22, 13, and 8, respectively. The efficacy was significant better in the two experimental groups than in the control group (both P < 0.01), although no significant difference was noted between the two experimental groups. The 6-, 12-, and 24-month survival rates were 80.4%, 72.7% and 23.6% in the intratumoral injection group, 77.4%, 67.7% and 21.3% in the hepatic artery perfusion group, and 56.8%, 47.7% and 14% in the control group. Although there was no significant difference in survival rates between the two experimental groups, the 6- and 12-month survival rates were significantly better in the two experimental groups than in the control group (all P < 0.05). However, there was no significant difference in the 24-month survival rate between the three groups. No serious adverse reactions were observed in the two experimental groups.

CONCLUSION: Gendicine can enhance the efficacy of interventional chemotherapy for primary hepatocarcinoma, with no increase in serious adverse events. The efficacy of intratumoral injection of Gendicine is not superior to hepatic arterial infusion of Gendicine.

Radiofrequency ablation and immunostimulant OK-432: combination therapy enhances systemic antitumor immunity for treatment of VX2 lung tumors in rabbits

PURPOSE

To evaluate whether antitumor immunity is enhanced systemically by combining radiofrequency ablation (RFA) and local injection of an immunostimulant, OK-432.

MATERIALS AND METHODS

Experiments were approved by the institutional animal care committee. Experimental Japanese rabbits inoculated with VX2 tumors in the lung and the auricle were randomized into four groups of eight: control (supportive care), RFA (RFA of lung tumor), OK-432 (direct injection of OK-432 into lung tumor), and combination therapy (lung RFA and direct OK-432 injection into lung tumor). All procedures were performed 1 week after implantation of VX2 tumors (week 1). In addition, a VX2 tumor rechallenge test was performed in the RFA and combination therapy groups. Survival time was evaluated by means of the Kaplan-Meier method and by using the log-rank test for intergroup comparison. Mean auricle tumor volumes were calculated every week. Specific growth rates (SGRs) were calculated and compared by using the Mann-Whitney test.

RESULTS

The median survival times of the control, RFA, OK-432, and combination therapy groups were 23, 36.5, 46.5, and 105 days, respectively. Survival was significantly prolonged in the combination therapy group when compared with the other three groups (P <.05). The mean auricle tumor volume decreased only in the combination therapy group. The mean auricle tumor volumes of the combination therapy group from week 1 to week 7 were 205, 339, 264, 227, 143, 127, and 115 mm(3). SGR in the combination therapy group became significantly smaller than those in the other three groups (P < .05). In the rechallenge test, the volume of all reimplanted tumors decreased.

CONCLUSION

Combining RFA with local injection of immunostimulant OK-432 may lead to indirectly activation of systemic antitumor immunity.