Efficacy of dendritic cell-cytokine-induced killer immunotherapy plus intensity-modulated radiation therapy in treating elderly patients with esophageal carcinoma

Present situation and prospect of immunotherapy for unresectable locally advanced esophageal cancer during peri-radiotherapy

Four major studies (Checkmate577, Keynote-590, Checkmate649 and Attraction-4) of locally advanced esophageal cancer published in 2020 have established the importance of immunotherapy, represented by anti-programmed death protein (PD)-1 in postoperative adjuvant treatment and advanced first-line treatment of locally advanced or advanced esophageal cancer and esophagogastric junction cancer, from the aspects of proof of concept, long-term survival, overall survival rate and progression-free survival. For unresectable or inoperable nonmetastatic esophageal cancer, concurrent radiotherapy and chemotherapy is the standard treatment recommended by various guidelines. Because its curative effect is still not ideal, it is necessary to explore radical radiotherapy and chemotherapy in the future, and it is considered to be promising to combine them with immunotherapeutic drugs such as anti-PD-1. This paper mainly discusses how to combine radical concurrent radiotherapy and chemotherapy with immunotherapy for unresectable local advanced esophageal cancer.

Cytokine-induced killer cells/dendritic cells and cytokine-induced killer cells immunotherapy for the treatment of esophageal cancer: A meta-analysis

OBJECTIVES

This meta-analysis was designed to systematically evaluate whether autologous cytokine-induced killer cells (CIK) or dendritic cells and cytokine-induced killer cells (DC-CIK) immunotherapy combined with chemotherapy can improve the therapeutic effect and safety of chemotherapy in esophageal cancer (EC).

MATERIALS AND METHODS

Randomized controlled trials (RCTs) were electronically searched databases including CNKI, WanFang, WeiPu, CBMDisc, PubMed, Web of Science, EMbase, the Cochrane Library, and Clinical Trials. The databases were searched for articles published until June 2019. Two researchers independently screened the literature, extracted data, and evaluated the quality of the included literature. Meta-analysis was performed using RevMan5.3.

RESULTS

Seventeen studies (1416 participants) were included. The differences between CIK/DC-CIK combination chemotherapy and chemotherapy alone were significant. The results displayed that the number of CD3+, CD4+, CD4+/CD8+, and NK cells was significantly increased after 1 to 2 weeks of treatment with CIK/DC-CIK cells in the treatment group (all P < .05). In addition, the results shown that 1-year overall survival was significantly prolonged (P < .0001) and quality of life was improved (P = .001) in EC chemotherapy combined with immunotherapy groups compared with conventional treatment. Furthermore, cytokine expression levels of interleukin 2 (IL-2), tumor necrosis factor α (TNF-α), and interleukin 12 (IL-12) were significantly increased (P = .0003) as well as the levels of immunoglobulins were elevated (P < .00001). Serum levels of tumor marker molecules, carcinoembryonic antigen (CEA), carbohydrate antigen (CA)-199, and CA-125 were lower in treatment groups than that of control groups (P < .00001). No fatal adverse reactions were noted (P = .04).

CONCLUSIONS

It is safe and effective for patients to use chemotherapy combined with CIK/DC-CIK immunotherapy. Immunotherapy can simultaneously improve the antitumor immune response. Specifically, DC-CIK cells can increase T lymphocyte subsets, CIK cells, NK cells, and immunoglobulins in peripheral blood to enhance antitumor immunity. Therefore, combination therapy enhances the immune function and improves the therapeutic efficacy of patients with EC.

Effective combinations of radiotherapy and immunotherapy in the treatment of esophageal squamous cell carcinoma

The traditional treatments for esophageal squamous cell carcinoma include surgery and radiation as local therapies, then chemotherapy and targeted therapy as systemic treatments. These treatments, either alone or in combination, however, are not satisfactory because of limited efficacy and unfavorable toxicity, calling for new therapeutic strategies. In recent years, immunotherapy, a new weapon in the arsenal against cancer, has shown substantial clinical benefits in patients with esophageal squamous cell carcinoma, particularly ones with locally advanced or metastatic disease. Importantly, accumulating evidence suggests that traditional radiation therapy functions as a powerful adjuvant for immunotherapy by contributing to systemic antitumor immunity, resulting in reduced recurrence risk and improved survival of patients. Here the authors summarize the emerging data on immunotherapy- and radiation therapy-based treatment of esophageal squamous cell carcinoma and discuss the pros and cons of different combinations, aiming at a comprehensive understanding of the proper rationale for the design of effective therapeutic regimens.

Immunotherapy in gastroesophageal cancers: Current state and future directions

While gastroesophageal (GE) cancers are one of the most common cancers worldwide, unfortunately, the mortality remains high. Commonly used treatment options include surgical resection, chemotherapy, radiotherapy, and molecular targeted therapy, which improve survival only minimally; thus, affirming the dire need for exploring alternative strategies to improve patient outcomes. Immunotherapy, which has revolutionized the world of oncology, has somewhat lagged behind in GE malignancies. Tumor-associated microenvironment and regulatory T cells, alongside cell cycle checkpoints, have been proposed by various studies as the mediators of carcinogenesis in GE cancers. Thus, inhibition of each of these could serve as a possible target of treatment. While the approval of pembrolizumab has provided some hope, it is not enough to override the dismal prognosis that this disease confers. Herein, we discuss the prospects of immunotherapy in this variety of cancer.

Synergism Between Immunotherapy and Radiotherapy in Esophageal Cancer: An Overview of Current Knowledge and Future Perspectives

Background: Esophageal cancer (EC) is an aggressive neoplasm of the gastrointestinal tract that is usually treated with a combination of chemotherapy, radiotherapy (RT), and/or surgery, according to disease status. Despite the availability of multimodal therapeutic strategies, local recurrence is frequently observed. Immunotherapy is a promising therapeutic approach that is currently highly investigated in association to standard therapies, including RT, with the aim to improve patients' outcomes. Materials and Methods: A PubMed search was performed with the following keywords in all fields: "esophageal cancer" and "radiotherapy" and "radiation" and "immunotherapy" and "PD-1" and "PD L1." For an overview of ongoing trials, an additional search on ClinicalTrials.gov website was performed using the keywords "esophageal cancer" and "immunotherapy" and "PD-L1" and "CTLA-4" and "radiation" and "radiotherapy." Emerging data from preclinical and clinical studies are suggesting a synergistic effect between immunotherapy and RT. With the aim to update the knowledge of this synergistic immune-mediated antitumor activity and discuss current challenges, the authors summarize published data concerning the basic mechanisms and the effectiveness and tolerance of the combination between immunotherapy and RT for patients with EC, followed by an overview of ongoing clinical trial. Conclusions: Published results encourage the use of personalized therapeutic approaches for EC patients in the future; results from ongoing studies will help to identify the optimal strategies for patient selection and treatment response evaluation.

Ten-year update of the international registry on cytokine-induced killer cells in cancer immunotherapy

Cytokine-induced killer (CIK) cells represent an exceptional T-cell population uniting a T cell and natural killer cell-like phenotype in their terminally differentiated CD3⁺ CD56⁺ subset, which features non-MHC-restricted tumor-killing activity. CIK cells have provided encouraging results in initial clinical studies and revealed synergistic antitumor effects when combined with standard therapeutic procedures. We established the international registry on CIK cells (IRCC) to collect and evaluate clinical trials for the treatment of cancer patients in 2010. Moreover, our registry set new standards on the reporting of results from clinical trials using CIK cells. In the present update, a total of 106 clinical trials including 10,225 patients were enrolled in IRCC, of which 4,889 patients in over 30 distinct tumor entities were treated with CIK cells alone or in combination with conventional or novel therapies. Significantly improved median progression-free survival and overall survival were shown in 27 trials, and 9 trials reported a significantly increased 5-year survival rate. Mild adverse effects and graft-versus-host diseases were also observed in the studies. Recently, more efforts have been put into the improvement of antitumoral efficacy by CIK cells including the administration of immune checkpoint inhibitors and modification with chimeric antigen receptorc. The minimal toxicity and multiple improvements on their tumor-killing activity both make CIK cells a favorable therapeutic tool in the clinical practice of cancer immunotherapy.

Immunotherapy and radiation therapy for gastrointestinal malignancies: hope or hype?

Immunotherapy represents the newest pillar in cancer care. Although there are increasing data showing the efficacy of immunotherapy there is a spectrum of response across unselected populations of cancer patients. In fact, response rates can be poor even among patients with immunogenic tumors for reasons that remain poorly understood. A promising clinical strategy to improve outcomes, which is supported by an abundance of preclinical data, is combining immunotherapy with radiation therapy. Here we review the existing evidence and future directions for combining immunotherapy and radiation therapy for patients with gastrointestinal cancers.

Dendritic cell-based vaccination: powerful resources of immature dendritic cells against pancreatic adenocarcinoma

Pancreatic adenocarcinoma (PAC) has a poor prognosis. One treatment approach, investigated here, is to reinforce antitumor immunity. Dendritic cells (DCs) are essential for the development and regulation of adaptive host immune responses against tumors. A major role for DCs may be as innate tumoricidal effector cells. We explored the efficacy of vaccination with immature (i)DCs, after selecting optimal conditions for generating immunostimulatory iDCs. We used two models, C57BL/6Jrj mice with ectopic tumors induced by the PAC cell line, Panc02, and genetically engineered (KIC) mice developing PAC. Therapeutic iDC-vaccination resulted in a significant reduction in tumor growth in C57BL/6Jrj mice and prolonged survival in KIC mice. Prophylactic iDC-vaccination prevented subcutaneous tumor development. These protective effects were long-lasting in Panc02-induced tumor development, but not in melanoma. iDC-vaccination impacted the immune status of the hosts by greatly increasing the percentage of CD8⁺ T-cells, and natural killer (NK)1.1⁺ cells, that express granzyme B associated with Lamp-1 and IFN-γ. Efficacy of iDC-vaccination was CD8⁺ T-cell-dependent but NK1.1⁺ cell-independent. We demonstrated the ability of DCs to produce peroxynitrites and to kill tumor cells; this killing activity involved peroxynitrites. Altogether, these findings make killer DCs the pivotal actors in the beneficial clinical outcome that accompanies antitumor immune responses. We asked whether efficacy can be improved by combining DC-vaccination with the FOLFIRINOX regimen. Combined treatment significantly increased the lifespan of KIC mice with PAC. Prolonged treatment with FOLFIRINOX clearly augmented this beneficial effect. Combining iDC-vaccination with FOLFIRINOX may therefore represent a promising therapeutic option for patients with PAC.

Clinical value of Pro-GRP and T lymphocyte subpopulation for the assessment of immune functions of lung cancer patients after DC-CIK biological therapy

The present study investigated the aptness of assessing the levels of progastrin-releasing peptide (Pro-GRP) in addition to the T lymphocyte subpopulation in lung cancer patients prior to and after therapy for determining immune function. A total of 45 patients with lung cancer were recruited and stratified in to a non-small cell lung cancer (NSCLC) and an SCLC group. Prior to and after treatment by combined biological therapy comprising chemotherapy or chemoradiotherapy followed by three cycles of retransformation of autologous dendritic cells-cytokine-induced killer cells (DC-CIK), the peripheral blood was assessed for populations of CD3⁺, CD4⁺, CD8⁺ and regulatory T cells (Treg) by flow cytometry, and for the levels of pro-GRP, carcinoembryonic antigen, neuron-specific enolase and Cyfra 21-1. The results revealed that in NSCLC patients, CD8⁺ T lymphocytes and Treg populations were decreased, and that CD3⁺ and CD4⁺ T lymphocytes as well as the CD4⁺/CD8⁺ ratio were increased after therapy; in SCLC patients, CD3⁺, CD4⁺ and CD8⁺ T lymphocytes were increased, while Treg cells were decreased after treatment compared with those at baseline. In each group, Pro-GRP was decreased compared with that prior to treatment, and in the SCLC group only, an obvious negative correlation was identified between Pro-GRP and the T lymphocyte subpopulation. Furthermore, a significant correlation between Pro-GRP and Tregs was identified in each group. In conclusion, the present study revealed that the immune function of the patients was improved after biological therapy. The results suggested a significant correlation between Pro-GRP and the T lymphocyte subpopulation in SCLC patients. Detection of Pro-GRP may assist the early clinical diagnosis of SCLC and may also be used to assess the immune regulatory function of patients along with the T lymphocyte subpopulation. Biological therapy with retransformed autologous DC-CIK was indicated to enhance the specific elimination of tumor cells and improve the immune surveillance function in cancer patients, and also restrained the immune evasion of the tumor, leading to decreased Pro-GRP levels.

Cell-based immunotherapy with cytokine-induced killer (CIK) cells: From preparation and testing to clinical application

Cell-based immunotherapy holds promise in the quest for the treatment of cancer, having potential synergy with surgery, chemotherapy and radiotherapy. As a novel approach for adoptive cell-based immunotherapy, cytokine-induced killer (CIK) cells have moved from the 'bench to bedside'. CIK cells are a heterogeneous subset of ex-vitro expanded, polyclonal T-effector cells with both natural killer (NK) and T-cell properties, which present potent non-major histocompatibility complex-restricted cytotoxicity against a variety of tumor target cells. Initial clinical studies on CIK cell therapy have provided encouraging results and revealed synergistic antitumor effects when combined with standard therapeutic procedures. At the same time, issues such as inadequate quality control and quantity of CIK cells as well as exaggerated propaganda were continuously emerging. Thus, the Ministry of Health in China stopped CIK cell therapy in May 2016, which was a major setback for the innovation of CIK cell-based immunotherapy. Thus, it is very important to modify technical criteria to develop a standardized operation procedure (SOP) and standardized system for evaluating antitumor efficacy in a safe way.

Trial watch: Dendritic cell-based anticancer immunotherapy

Dendritic cell (DC)-based vaccines against cancer have been extensively developed over the past two decades. Typically DC-based cancer immunotherapy entails loading patient-derived DCs with an appropriate source of tumor-associated antigens (TAAs) and efficient DC stimulation through a so-called "maturation cocktail" (typically a combination of pro-inflammatory cytokines and Toll-like receptor agonists), followed by DC reintroduction into patients. DC vaccines have been documented to (re)activate tumor-specific T cells in both preclinical and clinical settings. There is considerable clinical interest in combining DC-based anticancer vaccines with T cell-targeting immunotherapies. This reflects the established capacity of DC-based vaccines to generate a pool of TAA-specific effector T cells and facilitate their infiltration into the tumor bed. In this Trial Watch, we survey the latest trends in the preclinical and clinical development of DC-based anticancer therapeutics. We also highlight how the emergence of immune checkpoint blockers and adoptive T-cell transfer-based approaches has modified the clinical niche for DC-based vaccines within the wide cancer immunotherapy landscape.

Cytokine-induced killer cells/dendritic cells and cytokine-induced killer cells immunotherapy for the treatment of esophageal cancer in China: a meta-analysis

BACKGROUND

Immunotherapy based on cytokine-induced killer cells or combination of dendritic cells and cytokine-induced killer cells (CIK/DC-CIK) showed promising clinical outcomes for treating esophageal cancer (EC). However, the clinical benefit varies among previous studies. Therefore, it is necessary to systematically evaluate the curative efficacy and safety of CIK/DC-CIK immunotherapy as an adjuvant therapy for conventional therapeutic strategies in the treatment of EC.

MATERIALS AND METHODS

Clinical trials published before October 2016 and reporting CIK/DC-CIK immunotherapy treatment responses or safety for EC were searched in Cochrane Library, EMBASE, PubMed, Wanfang and China National Knowledge Internet databases. Research quality and heterogeneity were evaluated before analysis, and pooled analyses were performed using random- or fixed-effect models.

RESULTS

This research covered 11 trials including 994 EC patients. Results of this meta-analysis indicated that compared with conventional therapy, the combination of conventional therapy with CIK/DC-CIK immunotherapy significantly prolonged the 1-year overall survival (OS) rate, overall response rate (ORR) and disease control rate (DCR) (1-year OS: P=0.0005; ORR and DCR: P<0.00001). Patients with combination therapy also showed significantly improved quality of life (QoL) (P=0.02). After CIK/DC-CIK immunotherapy, lymphocyte percentages of CD3⁺ and CD3^-CD56⁺ subsets (P<0.01) and cytokines levels of IFN-γ, -2, TNF-α and IL-12 (P<0.00001) were significantly increased, and the percentage of cluster of differentiation (CD)4⁺CD25⁺CD127^- subset was significantly decreased, whereas analysis of CD4⁺, CD8⁺, CD4⁺/CD8⁺ and CD3⁺CD56⁺ did not show significant difference (P>0.05).

CONCLUSION

The combination of CIK/DC-CIK immunotherapy and conventional therapy is safe and markedly prolongs survival time, enhances immune function and improves the treatment efficacy for EC.

Risks and Benefits of Multimodal Esophageal Cancer Treatments: A Meta-Analysis

BACKGROUND Esophageal cancer has traditionally been associated with very poor outcomes. A number of therapies are available for the treatment and palliation of esophageal cancer, but little systematic evidence compares the efficacy of different treatment strategies. This meta-analysis aimed to investigate whether treatments in addition to radiotherapy could provide better efficacy and safety. MATERIAL AND METHODS We identified a total of 12 eligible studies with 18 study arms by searching PubMed, the Cochrane Library, EMBASE, and Clinical Trials.gov without time or language restrictions. The final search was conducted on 17 August 2016. We calculated mean differences (MD) and risk ratios (RR) with 95% confidence intervals (CI) for continuous and dichotomous data, respectively. Heterogeneity was calculated and reported using Tau², Chi², and I² analyses. RESULTS Twelve studies with 18 study arms were included in the analysis. Addition of surgery to chemo-radiotherapy resulted in improved median survival time (p=0.009) compared with chemo-radiotherapy alone, but all other outcomes were unaffected. Strikingly, and in contrast with patients with squamous cell carcinomas, the subset of patients with adenocarcinoma who received therapies in addition to radiotherapy showed a significant improvement in median survival time (p<0.0001), disease-free survival (p=0.007), 2-year survival rates (p=0.002), and 3-year survival rates (p=0.01). The incidence of adverse effects increased substantially with additional therapies. CONCLUSIONS This meta-analysis reveals stark differences in outcomes in patients depending on the type of carcinoma. Patients with squamous cell carcinoma should be educated about the risks and benefits of undergoing multiple therapies.

Cytokine-induced killer cell infusion combined with conventional treatments produced better prognosis for hepatocellular carcinoma patients with barcelona clinic liver cancer B or earlier stage: A systematic review and meta-analysis

BACKGROUND AIMS

To investigate the clinical benefits of cytokine-induced killer (CIK) cell infusions on hepatocellular carcinoma (HCC) patients, combined with other conventional treatments.

METHODS

This was a systematic review and meta-analysis conducted among phase II and III randomized control trials worldwide. Review manager 5.2 version was used to pool the effect size across studies. Sensitivity analyses and risk of bias were estimated among included studies. Egger's test was used to characterize the publication bias.

RESULTS

Eight randomized controlled trials and 945 patients with HCC were included in the study. CIK infusion reduced cancer recurrence risk to 0.74 (95% confidence interval [CI] 0.5-0.92), I² 75% (P <0.001), and reduced cancer death risk to 0.76 (95% CI 0.65-0.88), I² 50% (P = 0.09). Among studies blinded for outcome assessment and Barcelona Clinic Liver Cancer stages of 0, A and B, CIK infusion reduced recurrence risk by 18% (relative risk [RR] = 0.82, 95% CI 0.70-0.96) and death risk by 37% (RR = 0.63, 95% CI 0.47-0.85); heterogeneity was 0% and 39%, respectively (P > 0.05). The intercepts of linear regressions for recurrence and death were -2.17 and -2.07, respectively, but the P value was 0.17 and 0.38; no significant publication bias was observed with Egger's test.

DISCUSSION

Among hepatocellular carcinoma patients with Barcelona Clinic Liver Cancer score of B or less, CIK cell infusions combined with conventional treatments significantly prolonged recurrence-free and overall survival. This adoptive immunotherapy could be recommended to HCC patients.