Interleukin-15 enhances cytokine induced killer (CIK) cytotoxic potential against epithelial cancer cell lines via an innate pathway

Autologous CIK cells combined with chemotherapy as the first-line treatment for locally advanced or metastatic gastric cancer is safe and feasible

Aim

To evaluate the safety and initial efficacy of autologous cytokine-induced killer (CIK) cells combined with S-1+oxaliplatin (SOX) as the first-line treatment for locally advanced or metastatic gastric cancer (GC).

Materials and methods

In this two-arm, single-center exploratory trial, patients with locally advanced or metastatic GC were randomly assigned (1:1) to receive autologous CIK cells in combination with SOX (CIK-SOX) or SOX alone. The primary endpoint was the incidence of adverse events (AEs). Progression-free survival (PFS), overall survival (OS), objective response rate (ORR), and disease control rate (DCR) served as the secondary endpoints.

Results

Fifty-nine patients were enrolled in the study between November 20, 2014 and September 6, 2017. A total of 31 patients received CIK-SOX and 28 patients received SOX. The most common AEs in both groups were gastrointestinal reaction, leucopenia, neutropenia, anemia, thrombocytopenia, hyperbilirubinemia, and elevated aspartate transaminase concentration, with a higher incidence of these conditions in the SOX group. The median PFS for the CIK-SOX and SOX groups was 6.9 and 4.9 months, respectively (hazard ratio (HR) 0.80, p=0.45). The respective median OS values were 17.8 and 9.75 months (HR 0.76, p=0.34). Patients who received more than three injections of specific lymphocyte subsets benefited the most from this combination therapy. Cox univariate and multivariate analyses showed that tumor metastasis to more than two organs was the main risk factor for PFS and OS. A total of 29 patients in the CIK-SOX group and 25 in the SOX group had measurable lesions. The ORR for the CIK-SOX and SOX groups was 55.2% and 32.0%, while the DCR was 93.1% and 88.0%, respectively.

Conclusion

The safety of CIK-SOX as the first-line treatment for patients with locally advanced or metastatic GC was good. Although the PFS and OS in the CIK-SOX group were not statistically significantly different compared to the values in the SOX alone group, this treatment increased the PFS and OS duration, with the absolute improvement in OS of about 8.05 months. Continuous benefit from the CIK-SOX treatment was observed during long-term follow-up.

Clinical trial registration

https://clinicaltrials.gov/study/NCT02504229?term=NCT02504229&rank=1, identifier ChiCTR-IPR-15005923; NCT02504229.

IL-15-induced lymphocytes as adjuvant cellular immunotherapy for gastric cancer

Objectives To test the antitumor potential of lymphocytes transferred via adoptive cell therapy (ACT) in a mouse model of human gastric cancer (GC), and to evaluate the clinical efficacy and safety of combining lymphocytes as adjuvant therapy with first-line chemotherapy in patients with GC. Methods We constructed a human GC xenograft model in sublethally irradiated 6-8-week-old male NCG mice. MKN-45 cells (1 × 10⁶ cells/mouse) were subcutaneously injected into mice's flanks. After tumors had become palpable, we randomized the mice into control, ACT^IL-2, and ACT^IL-15 groups. Human lymphocytes were then injected into mouse tail veins. In addition, 63 human patients with histologically or cytologically confirmed stage III-IV GC randomly received S-1 + oxaliplatin + ACT^IL-15 (combination therapy group) or S-1 + oxaliplatin (chemotherapy group). Results In the mouse study, treatment with ACT^IL-15 cells inhibited tumor growth on adoptive transfer, and mice that received ACT^IL-15 cells had significantly longer survival rates (p < 0.05, ACT^IL-15 vs. ACT^IL-2). In the human study, the median survival rate of patients in the combination therapy group was 472 days (95% confidence interval [CI], 276-668 days), whereas that of patients in the chemotherapy group was 266 days (95% CI, 200-332 days; p < 0.05). Eleven percent (7/63) of patients had adverse reactions, but these reactions did not interfere with treatment. Conclusion Adoptive transfer of ACT^IL-15 cells in a mouse model of GC and in patients with advanced GC treated with S1 + oxaliplatin improved survival rates in both, with an acceptable safety profile.

Research progress and clinical prospect of immunocytotherapy for the treatment of hepatocellular carcinoma

As a common malignant tumor, hepatocellular carcinoma (HCC) has high fatality rate due to its strong metastasis and high degree of malignancy. Current treatment strategies adopted in clinical practice were still conventional surgery, assisted with interventional therapy, radiotherapy and chemotherapy. However these treatments have limited effects with high recurrence rate. Current research progress of immunocytotherapy has shown that tumor cells can be directly identified and killed by stimulating the immune function and enhancing the anti-tumor immunity in tumor microenvironment. Targeted immunotherapeutics have therefore become the hope of conquering cancer in the future. It can kill tumor cells without damaging the body's immune system and function, restore and strengthen the body's natural anti-tumor immune system. It can reduce the toxic side effects of radiotherapy and chemotherapy, reduce the recurrence rate and prolong the survival period of patients with HCC. Currently, the immune cells widely studied are mainly as follows: Dendritic cells (DC), Cytokine-induced killer (CIK), DC-CIK, Chimeric antigen receptor T cells (CAR-T), Tumor infiltrating lymphocyte (TIL) and Natural killer cell (NK). Immunocytotherapy is a long-term treatment method, some studies have combined traditional therapy with immunocytotherapy and achieved significant effects, providing experimental basis for the application of immunocytotherapy. However, there are still some difficulties in the clinical application of immune cells. In this article, we discuss the application of immunocytotherapy in the clinical treatment of HCC, their effectiveness either alone or in combination with conventional therapies, and how future immunocytotherapeutics can be further improved from investigations in tumour immunology.

Clinical Trials with Combination of Cytokine-Induced Killer Cells and Dendritic Cells for Cancer Therapy

Adoptive cellular immunotherapy (ACI) is a promising treatment for a number of cancers. Cytokine-induced killer cells (CIKs) are considered to be major cytotoxic immunologic effector cells. Usually cancer cells are able to suppress antitumor responses by secreting immunosuppressive factors. CIKs have significant antitumor activity and are capable of eradicating tumors with few side effects. They are a very encouraging cell population used against hematological and solid tumors, with an inexpensive expansion protocol which could yield to superior clinical outcome in clinical trials employing adoptive cellular therapy combination. In the last decade, clinical protocols have been modified by enriching lymphocytes with CIK cells. They are a subpopulation of lymphocytes characterized by the expression of CD3+ and CD56+ wich are surface markers common to T lymphocytes and natural killer NK cells. CIK cells are mainly used in two diseases: in hematological patients who suffer relapse after allogeneic transplantation and in patients with hepatic carcinoma after surgical ablation to eliminate residual tumor cells. Dendritic cells DCs could play a pivotal role in enhancing the antitumor efficacy of CIKs.

Analytic and Dynamic Secretory Profile of Patient-Derived Cytokine-Induced Killer Cells

Adoptive immunotherapy with Cytokine Induced Killer (CIK) cells has shown antitumor activity against several kinds of cancers in preclinical models and clinical trials. CIK cells are a subset of ex vivo expanded T lymphocytes with T-NK phenotype and MHC-unrestricted antitumor activity. Literature provides scanty information on cytokines, chemokines and growth factors secreted by CIK cells. Therefore, we investigated the secretory profile of CIK cells generated from tumor patients. The secretome analysis was performed at specific time points (day 1, day 14 and day 21) of CIK cells expansion. Mature CIK cells (day 21) produce a great variety of interleukins and secreted proteins that can be divided into 3 groups based on their secretion quantity: high (IL-13, RANTES, MIP-1α and 1β), medium (IL-1Ra, IL-5, IL-8, IL-10, IL-17, IP-10, INF-γ, VEGF and GMCSF) and low (IL-1β, IL-4, IL-6, IL-7, IL-9, IL-12, IL-15, Eotaxin, PDGF-bb, FGF basic, G-CSF and MCP-1) secreted. Moreover, comparing PBMC (day 1) and mature CIK cells (day 14 and 21) secretome, we observed that IL-5, IL-10, IL-13, GM-CSF, VEGF resulted greatly up-regulated, while IL-1β, IL-6, IL-8, IL-15, IL-17, eotaxin, MCP-1, and RANTES were down-regulated. We also performed a gene expression profile analysis of patient-derived CIK cells showing that mRNA for the different cytokines and secreted proteins were modulated during PBMC to CIK differentiation. We highlighted previously unknown secretory properties and provided for the first time a comprehensive molecular characterization of CIK cells. Our findings provide rationale to explore the functional implications and possible therapeutic modulation of CIK secretome.

Cytokine-Induced Killer Cells As Pharmacological Tools for Cancer Immunotherapy

Cytokine-induced killer (CIK) cells are a heterogeneous population of effector CD3⁺CD56⁺ natural killer T cells, which can be easily expanded in vitro from peripheral blood mononuclear cells. CIK cells work as pharmacological tools for cancer immunotherapy as they exhibit MHC-unrestricted, safe, and effective antitumor activity. Much effort has been made to improve CIK cells cytotoxicity and treatments of CIK cells combined with other antitumor therapies are applied. This review summarizes some strategies, including the combination of CIK with additional cytokines, dendritic cells, check point inhibitors, antibodies, chemotherapeutic agents, nanomedicines, and engineering CIK cells with a chimeric antigen receptor. Furthermore, we briefly sum up the clinical trials on CIK cells and compare the effect of clinical CIK therapy with other immunotherapies. Finally, further research is needed to clarify the pharmacological mechanism of CIK and provide evidence to formulate uniform culturing criteria for CIK expansion.