The past, present and future of immunotherapy against tumor

Neutrophil-to-Lymphocyte Ratio Is a Major Prognostic Factor in Non-small Cell Lung Carcinoma Patients Undergoing First Line Immunotherapy With Pembrolizumab

BACKGROUND/AIM

Lung cancer is one of the most common malignant neoplastic diseases and by far the leading cause of cancer death worldwide. Recently, immune checkpoint inhibitors (ICIs) have received increasing attention for playing a crucial role in non-small cell lung cancer (NSCLC). Biomarkers, such as programmed cell death-ligand 1 (PD-L1) and tumor mutational burden (TMB), seemed to be helpful in selecting patients who are more likely to benefit from ICI treatment: however, their role has not yet been fully clarified.

PATIENTS AND METHODS

In this retrospective study, we evaluated the relationship between pre-treatment peripheral blood neutrophil-to-lymphocyte ratio (NLR) and survival in 252 patients suffering from advanced NSCLC who had received pembrolizumab as their first-line immunotherapy.

RESULTS

Compared to their NLR low counterparts who had a median overall survival (OS) of 34.8 months, patients with NLRs above 4.8 had a median OS of 7.6 months (HR=3.26, 95%Cl=2.3-4.6, p-value<0.0000001). In multivariate Cox regression analysis, alongside other variables, such as metastatic sites, age, and sex, NLR and PD-L1 predicted progression-free survival and OS; furthermore, a very high NLR - over 10 - seemed to forecast a very dismal prognosis in patients undergoing immunotherapy, with sudden deaths in the days immediately following therapy (median OS=3.8 months).

CONCLUSION

NLR acts as a valuable and reliable prognostic factor in non-small cell lung carcinoma patients undergoing first line immunotherapy with pembrolizumab. Additional investigation is necessary to fully elucidate the underlying biological rationale, which can be found in myeloid derived suppressor cells, a heterogeneous population of cells with neutrophil-like immunophenotypic features.

Assessing the Future of Solid Tumor Immunotherapy

With the advent of cancer immunotherapy, there has been a major improvement in patient’s quality of life and survival. The growth of cancer immunotherapy has dramatically changed our understanding of the basics of cancer biology and has altered the standards of care (surgery, radiotherapy, and chemotherapy) for patients. Cancer immunotherapy has generated significant excitement with the success of chimeric antigen receptor (CAR) T cell therapy in particular. Clinical results using CAR-T for hematological malignancies have led to the approval of four CD19-targeted and one B-cell maturation antigen (BCMA)-targeted cell therapy products by the US Food and Drug Administration (FDA). Also, immune checkpoint inhibitors such as antibodies against Programmed Cell Death-1 (PD-1), Programmed Cell Death Ligand-1 (PD-L1), and Cytotoxic T-Lymphocyte-Associated Antigen 4 (CTLA-4) have shown promising therapeutic outcomes and long-lasting clinical effect in several tumor types and patients who are refractory to other treatments. Despite these promising results, the success of cancer immunotherapy in solid tumors has been limited due to several barriers, which include immunosuppressive tumor microenvironment (TME), inefficient trafficking, and heterogeneity of tumor antigens. This is further compounded by the high intra-tumoral pressure of solid tumors, which presents an additional challenge to successfully delivering treatments to solid tumors. In this review, we will outline and propose specific approaches that may overcome these immunological and physical barriers to improve the outcomes in solid tumor patients receiving immunotherapies.

Microenvironmental Metabolites in the Intestine: Messengers between Health and Disease

The intestinal mucosa is a highly absorptive organ and simultaneously constitutes the physical barrier between the host and a complex outer ecosystem. Intestinal epithelial cells (IECs) represent a special node that receives signals from the host and the environment and translates them into corresponding responses. Specific molecular communication systems such as metabolites are known to transmit information across the intestinal boundary. The gut microbiota or food-derived metabolites are extrinsic factors that influence the homeostasis of the intestinal epithelium, while mitochondrial and host-derived cellular metabolites determine the identity, fitness, and regenerative capacity of IECs. Little is known, however, about the role of intrinsic and extrinsic metabolites of IECs in the initiation and progression of pathological processes such as inflammatory bowel disease and colorectal cancer as well as about their impact on intestinal immunity. In this review, we will highlight the most recent contributions on the modulatory effects of intestinal metabolites in gut pathophysiology, with a particular focus on metabolites in promoting intestinal inflammation or colorectal tumorigenesis. In addition, we will provide a perspective on the role of newly identified oncometabolites from the commensal and opportunistic microbiota in shaping response and resistance to antitumor therapy.

Molecular Mechanisms of Resistance to Immunotherapy and Antiangiogenic Treatments in Clear Cell Renal Cell Carcinoma

Clear cell renal cell carcinoma (ccRCC) is the most common histological subtype arising from renal cell carcinomas. This tumor is characterized by a predominant angiogenic and immunogenic microenvironment that interplay with stromal, immune cells, and tumoral cells. Despite the obscure prognosis traditionally related to this entity, strategies including angiogenesis inhibition with tyrosine kinase inhibitors (TKIs), as well as the enhancement of the immune system with the inhibition of immune checkpoint proteins, such as PD-1/PDL-1 and CTLA-4, have revolutionized the treatment landscape. This approach has achieved a substantial improvement in life expectancy and quality of life from patients with advanced ccRCC. Unfortunately, not all patients benefit from this success as most patients will finally progress to these therapies and, even worse, approximately 5 to 30% of patients will primarily progress. In the last few years, preclinical and clinical research have been conducted to decode the biological basis underlying the resistance mechanisms regarding angiogenic and immune-based therapy. In this review, we summarize the insights of these molecular alterations to understand the resistance pathways related to the treatment with TKI and immune checkpoint inhibitors (ICIs). Moreover, we include additional information on novel approaches that are currently under research to overcome these resistance alterations in preclinical studies and early phase clinical trials.

A Review on Nano-Based Drug Delivery System for Cancer Chemoimmunotherapy

Although notable progress has been made on novel cancer treatments, the overall survival rate and therapeutic effects are still unsatisfactory for cancer patients. Chemoimmunotherapy, combining chemotherapeutics and immunotherapeutic drugs, has emerged as a promising approach for cancer treatment, with the advantages of cooperating two kinds of treatment mechanism, reducing the dosage of the drug and enhancing therapeutic effect. Moreover, nano-based drug delivery system (NDDS) was applied to encapsulate chemotherapeutic agents and exhibited outstanding properties such as targeted delivery, tumor microenvironment response and site-specific release. Several nanocarriers have been approved in clinical cancer chemotherapy and showed significant improvement in therapeutic efficiency compared with traditional formulations, such as liposomes (Doxil®, Lipusu®), nanoparticles (Abraxane®) and micelles (Genexol-PM®). The applications of NDDS to chemoimmunotherapy would be a powerful strategy for future cancer treatment, which could greatly enhance the therapeutic efficacy, reduce the side effects and optimize the clinical outcomes of cancer patients. Herein, the current approaches of cancer immunotherapy and chemoimmunotherapy were discussed, and recent advances of NDDS applied for chemoimmunotherapy were further reviewed.

Pretreatment Neutrophil-to-Lymphocyte Ratio (NLR) May Predict the Outcomes of Advanced Non-small-cell Lung Cancer (NSCLC) Patients Treated With Immune Checkpoint Inhibitors (ICIs)

Background: Recent studies have demonstrated the predictive value of pretreatment neutrophil-to-lymphocyte ratio (NLR) in advanced cancers; however, the role of NLR in patients with advanced non-small-cell lung cancer (NSCLC) treated with immune checkpoint inhibitors (ICIs) remained to be explored. Thus, we aimed to investigate whether pretreatment NLR was associated with the outcomes of advanced NSCLC patients treated with ICIs.

Methods: A comprehensive literature research was first conducted in PubMed, the Cochrane Central Library, and Embase for studies that evaluated the association between pretreatment NLR and survival of advanced NSCLC patients with ICIs treatment. We then conducted a retrospective study in Chinese People's Liberation Army (PLA) General Hospital (Beijing, China) to validate these findings.

Results: A total of 17 eligible studies with 2,106 patients were included in our meta-analysis, of which, 12 studies reported progression-free survival (PFS), and 13 studies reported overall survival (OS). The pooled results showed that high pretreatment NLR was significantly associated with poorer PFS (HR = 1.44, 95% CI 1.26–1.65; P < 0.001) and OS (HR = 2.86, 95% CI 2.11–3.87; P < 0.001) compared with those with low pretreatment NLR. Subgroup analysis demonstrated that the association between baseline NLR and PFS remained significant except that the cut-off value of NLR was 3 (HR = 1.48, 95% CI 0.93–2.37; P = 0.098) and region of Asia (HR = 1.55, 95% CI 1.00–2.39; P = 0.051). These results were further validated in our retrospective study that patients with pretreatment NLR ≥ 6.0 had shorter PFS (median: 5.0 vs. 9.1 months, HR = 1.39; 95% CI 1.01–1.91; P = 0.02) and OS (median: 10.0 vs. 17.3 months, HR = 1.71; 95% CI 1.18–2.46; P < 0.001) compared with those with NLR < 6.0. The associations between NLR and survival were consistent in subgroup analysis stratified by age, gender, ECOG PS, histology, stage, smoking history, treatment, and prior lines of therapy. Dynamics of NLR (dNLR) that increased ≥3.0 from baseline was also significantly associated with worse PFS (median: 3.1 vs. 9.1 months; P = 0.01) and OS (median: 6.8 vs. 17.0 months; P < 0.0001).

Conclusions: Our study demonstrates that pretreatment NLR and dNLR from baseline are associated with the outcomes of advanced NSCLC patients treated with ICIs; however, it warrants further prospective studies.

Anti-PD-1 therapy combined with chemotherapy in patients with advanced biliary tract cancer

BACKGROUND

Evidence for the efficacy of immunotherapy in biliary tract cancer (BTC) is limited and unsatisfactory.

METHODS

Chinese BTC patients receiving a PD-1 inhibitor with chemotherapy, PD-1 inhibitor monotherapy or chemotherapy alone were retrospectively analyzed. The primary outcome was overall survival (OS). The key secondary outcomes were progression-free survival (PFS) and safety. Patients previously treated with any agent targeting T cell costimulation or immune checkpoints were excluded.

RESULTS

The study included 77 patients (a PD-1 inhibitor plus chemotherapy, n = 38; PD-1 inhibitor monotherapy, n = 20; chemotherapy alone, n = 19). The median OS was 14.9 months with a PD-1 inhibitor plus chemotherapy, significantly longer than the 4.1 months with PD-1 inhibitor monotherapy (HR 0.37, 95% CI 0.17-0.80, P = 0.001) and the 6.0 months with chemotherapy alone (HR 0.63, 95% CI 0.42-0.94, P = 0.011). The median PFS was 5.1 months with a PD-1 inhibitor plus chemotherapy, significantly longer than the 2.2 months with PD-1 inhibitor monotherapy (HR 0.59, 95% CI 0.31-1.10, P = 0.014) and the 2.4 months with chemotherapy alone (HR 0.61, 95% CI 0.45-0.83, P = 0.003). Grade 3 or 4 treatment-related adverse events were similar between the anti-PD-1 combination group and the chemotherapy alone group (34.2% and 36.8%, respectively).

CONCLUSIONS

Anti-PD-1 therapy plus chemotherapy is an effective and tolerable approach for advanced BTC.

Next Generation CAR T Cells for the Immunotherapy of High-Grade Glioma

High grade gliomas (HGG) comprise a heterogeneous group of brain malignancies with dismal prognosis. Current standard-of-care includes radiation, chemotherapy, and surgical resection when possible. Despite advances in each of these treatment modalities, survival rates for pediatric and adult HGG patients has remained largely unchanged over the course of several years. This is in stark contrast to the significant survival increases seen recently for a variety of hematological and other solid malignancies. The introduction and widespread use of immunotherapies have contributed significantly to these survival increases, and as such these therapies have been explored for use in the treatment of HGG. In particular, chimeric antigen receptor (CAR) T cell therapy has shown promise in clinical trials in HGG patients. However, unlike the tremendous success CAR T cell therapy has seen in B cell leukemia and lymphoma treatment, the success in HGG patients has been modest at best. This is largely due to the unique tumor microenvironment in the central nervous system, difficulty in accessing the tumor site, and heterogeneity in target antigen expression. The results of these features are poor CAR T cell proliferation, poor persistence, suboptimal cytokine secretion, and the emergence of antigen-loss tumor variants. These issues have called for the development of “next generation” CAR T cells designed to circumvent the barriers that have limited the success of current CAR T cell technologies in HGG treatment. Rapid advancements in gene editing technologies have provided several avenues for CAR T cell modification to enhance their efficacy. Among these are cytokine overexpression, gene knock-out and knock-in, targeting of multiple antigens simultaneously, and precise control of CAR expression and signaling. These “next generation” CAR T cells have shown promising results in pre-clinical models and may be the key to harnessing the full potential of CAR T cells in the treatment of HGG.

Clinical benefit from afatinib in an advanced squamous cell lung carcinoma patient harboring HER2 S310Y mutation: a case report

Background

HER2 mutations are identified in approximately 2% of non-small-cell lung cancer (NSCLC) cases and are predominantly observed in non-smokers, females, and adenocarcinoma patients. Although afatinib is recommended for treating NSCLC patients with HER2 mutation, the therapy is most efficacious in patients harboring HER2 exon 20 insertions, especially the in-frame insertion YVMA. Research on the treatment of the extracellular domain mutation is relatively rare.

Case presentation

We discuss a 76-year-old Chinese man with a heavy-smoking history who was diagnosed with stage IV squamous cell lung carcinoma. First-line treatment with the angiogenesis inhibitor endostar and systemic chemotherapy with docetaxel plus cisplatin were administered, but the patient ceased treatment because of chemotherapy-induced adverse events. Based on the test result from an amplification refractory mutation system PCR, EGFR-inhibitor icotinib was prescribed, but there was still no evidence of a response. Then, next-generation sequencing identified an HER2 S310Y mutation, and afatinib therapy resulted in a gradual, but substantial reduction in tumor size.

Conclusion

This is the first published case report of the successful management of HER2 S310Y mutation squamous cell lung carcinoma with afatinib. Considering the fact that this rare HER2 mutation clinically benefited from afatinib treatment, attention should be paid to the incidence of HER2 in NSCLC patients with inconsistent histological characteristics compared with those previous published. With the guidance of a precise diagnosis, we should realize the significance of other HER2 gene mutations and next-generation sequencing as a diagnostic method.

PD-L1 blockade enhances anti-tumor efficacy of NK cells

Anti-PD-1/anti-PD-L1 therapies have shown success in cancer treatment but responses are limited to ~ 15% of patients with lymphocyte infiltrated, PD-L1 positive tumors. Hence, strategies that increase PD-L1 expression and tumor infiltration should make more patients eligible for PD-1/PD-L1 blockade therapy, thus improving overall outcomes. PD-L1 expression on tumors is induced by IFNγ, a cytokine secreted by NK cells. Therefore, we tested if PM21-particle expanded NK cells (PM21-NK cells) induced expression of PD-L1 on tumors and if anti-PD-L1 treatment enhanced NK cell anti-tumor efficacy in an ovarian cancer model. Studies here showed that PM21-NK cells secrete high amounts of IFNγ and that adoptively transferred PM21-NK cells induce PD-L1 expression on SKOV-3 cells in vivo. The induction of PD-L1 expression on SKOV-3 cells coincided with the presence of regulatory T cells (Tregs) in the abdominal cavity and within tumors. In in vitro experiments, anti-PD-L1 treatment had no direct effect on cytotoxicity or cytokine secretion by predominantly PD-1 negative PM21-NK cells in response to PD-L1⁺ targets. However, significant improvement of NK cell anti-tumor efficacy was observed in vivo when combined with anti-PD-L1. PD-L1 blockade also resulted in increased in vivo NK cell persistence and retention of their cytotoxic phenotype. These results support the use of anti-PD-L1 in combination with NK cell therapy regardless of initial tumor PD-L1 status and indicate that NK cell therapy would likely augment the applicability of anti-PD-L1 treatment.

Skin Allografting Activates Anti-tumor Immunity and Suppresses Growth of Colon Cancer in Mice

INTRODUCTION: The tumor cells could escape from the immune elimination through the immunoediting mechanisms including the generation of immunosuppressive or immunoregulative cells. By contrast, allograft transplantation could activate the immune system and induce a strong allogenic response. The aim of this study was to investigate the efficacy of allogenic skin transplantation in the inhibition of tumor growth through the activation of allogenic immune response. METHODS: Full-thickness skin transplantation was performed from C57BL/6 (H-2^b) donors to BALB/c (H-2^d) recipients that were receiving subcutaneous injection of isogenic CT26 colon cancer cells (2 × 10⁶ cells) at the same time. The tumor size and pathological changes, cell populations and cytokine profiles were evaluated at day 14 post-transplantation. RESULTS: The results showed that as compared to non-transplant group, the allogenic immune response in the skin-grafting group inhibited the growth of tumors, which was significantly associated with increased numbers of intra-tumor infiltrating lymphocytes, increased populations of CD11c⁺MHC-classII⁺CD86⁺ DCs, CD3⁺CD4⁺ T cells, CD3⁺CD8⁺ T cells, and CD19⁺ B cells, as well as decreased percentage of CD4⁺CD25⁺Foxp3⁺ T cells in the spleens. In addition, the levels of serum IgM and IgG, tumor necrosis factor (TNF)-α and interferon (IFN)-γ were significantly higher within the tumor in skin transplant groups than that in non-transplant group. CONCLUSIONS: Allogenic skin transplantation suppresses the tumor growth through activating the allogenic immune response, and it may provide a new immunotherapy option for the clinical refractory tumor treatment.

Pretreatment neutrophil-to-lymphocyte ratio is associated with outcome of advanced-stage cancer patients treated with immunotherapy: a meta-analysis

BACKGROUND

To investigate the association between pretreatment blood neutrophil-to-lymphocyte ratio (NLR) and clinical outcomes for advanced-stage cancer patients treated with immunotherapy.

METHODS

We conducted a comprehensive literature search to assess the relationship between pretreatment blood NLR and overall survival (OS) or progression-free survival (PFS) in advanced-stage cancer patients treated with immunotherapy. Published data including hazard ratios (HRs) and related 95% confidence interval (CI) were extracted. Pooled estimates of treatment outcomes were calculated using RevMan 5.3.5.

RESULTS

Twenty-seven studies with 4647 patients were included in the current study. The pooled results suggested that high pretreatment blood NLR was correlated with significant shorter OS (HR = 1.98, 95% CI 1.66-2.36, P < 0.001) and PFS (HR = 1.78, 95% CI 1.48-2.15, P < 0.001). Subgroup analysis stratified by study targets revealed that anti-VEGF/VEGFR therapy (HR = 2.04, 95% CI 1.61-2.60, P < 0.001) and immune checkpoints blockade (HR = 2.16, 95% CI 1.86-2.51, P < 0.001) were significantly associated with inferior OS while other targets (HR = 1.63, 95% CI 0.89-2.99, P = 0.120) were not associated with OS. There was no correlation between distinct NLR cutoff values and OS ([Formula: see text] = 0.218, P = 0.329) or PFS benefit ([Formula: see text] = - 0.386, P = 0.140). Of note, HRs of PFS showed significant correlation with HRs of OS ([Formula: see text] = 0.656, P = 0.015).

CONCLUSION

Elevated pretreatment blood NLR was a promising prognostic and predictive biomarker for advanced-stage cancer patients treated with immunotherapy.

Inhibition of Phosphorylated c-Jun NH(2)-terminal Kinase by 2',4'-dihydroxy-6-methoxy-3,5-dimethylchalcone Isolated from Eugenia aquea Burm f. Leaves in Jurkat T-cells

Background:

Indonesian medicinal plants have been used for their anticancer activity for decades. However, the therapeutic effects of medicinal plants have not been fully examined scientifically. As cancer is a major health problem worldwide, searching for a new anticancer compound has attracted considerable attention. Our previous study found that 2’,4’-dihydroxy-6-methoxy-3,5-dimethylchalcone, an active compound isolated from leaves of Indonesian medicinal plants Eugenia aquea Burm f. (Myrtaceae), had anticancer activity in MCF-7 human breast cancer cells through induction of apoptosis.

Objective:

To investigate the molecular mechanism of 2’,4’-dihydroxy-6-methoxy-3,5-dimethylchalcone antiproliferative activity.

Materials and Methods:

Leaves of E. aquea were extracted by ethanol, fractionated by ethyl acetate, n-hexane, or water, and isolated for its active compound. Jurkat T-cells were treated with 2’,4’-dihydroxy-6-methoxy-3,5-dimethylchalcone for 12 and 24 h, and a cell viability assay and real-time-reverse transcriptase polymerase chain reaction for interleukin-2 (IL-2) mRNA measurement were performed. The effects of active compound to mitogen-activated protein kinases were also examined to investigate the mechanism of its antiproliferative activity.

Results:

2’,4’-dihydroxy-6-methoxy-3,5-dimethylchalcone inhibited Jurkat T-cell proliferation with a half maximal inhibitory concentration of 59.5 mM. Although IL-2 mRNA expression was slightly increased after treatment, it inhibited c-Jun N-terminal kinase expression but not p38 and extracellular signal-regulated kinase expression.

Conclusions:

Our study indicated that the molecular mechanism mediating the antiproliferative activity of 2’,4’-dihydroxy-6-methoxy-3,5-dimethylchalcone may be attributed to the stimulation of an immunological microenvironment in the cells.

SUMMARY

2’,4’-dihydroxy-6-methoxy-3,5-dimethylchalcone was isolated from Eugenia aquea. The antiproliferative activity of 2’,4’-dihydroxy-6- methoxy-3,5-dimethylchalcone significantly showed in Jurkat T-cells with a half maximal inhibitory concentration of 59.5 mM through inhibition of c-Jun N-terminal kinase phosphorylation. Interleukin-2 mRNA expression was also slightly increased after treatment with the compound, and this result may be indicated to the stimulation of the immunological microenvironment in T-cells.

Abbreviations used:E. aquea: Eugenia aquea, IL-2: Interleukin-2, MAPK: Mitogen-activated protein kinase, ERKs: Extracellular signal-regulated kinases, JNKs: c-Jun N-terminal kinases, p38: p38 MAPK, PI3K: Phosphatidylinositol-3 kinase, IC₅₀: Half maximal inhibitory concentration.

PD-1/PD-L1 Blockade Therapy for Tumors with Downregulated MHC Class I Expression

The therapy of different advanced-stage malignancies with monoclonal antibodies blocking programmed cell death protein 1 (PD-1)/PD-1 ligand 1 (PD-L1) signaling has had an impressive long-lasting effect in a portion of patients, but in most cases, this therapy was not successful, or a secondary resistance developed. To enhance its efficacy in treated patients, predictive biomarkers are searched for and various combination treatments are intensively investigated. As the downregulation of major histocompatibility complex (MHC) class I molecules is one of the most frequent mechanisms of tumor escape from the host’s immunity, it should be considered in PD-1/PD-L1 checkpoint inhibition. The potential for the use of a PD-1/PD-L1 blockade in the treatment of tumors with aberrant MHC class I expression is discussed, and some strategies of combination therapy are suggested.

Exosomes from Melatonin Treated Hepatocellularcarcinoma Cells Alter the Immunosupression Status through STAT3 Pathway in Macrophages

Immunosuppression is a significant factor in the progression of tumor invasion and metastasis. Melatonin, a well-known hormone, has certain cytotoxic and immune regulatory effects to inhibit tumor function. Exosomes are small membrane vesicles released by many kinds of cells, which contain different macromolecules, such as mRNAs and microRNAs (miRNAs), and proteins that can mediate communications between cells. Tumor-derived exosomes may cause immunosuppression, however, it is unknown whether melatonin can attenuate an immunosuppressive status by altering the function of tumor-derived exosomes. In the present study, we evaluated the effects of hepatocellularcarcinoma-derived exosomes (Exo-con) and exosomes derived from hepatocellularcarcinoma cells treated with 0.1 mM melatonin (Exo-MT), on the expression of inflammatory factors and programmed death ligand 1(PD-L1) by co-culturing Exo-con and Exo-MT, respectively, with macrophages differentiated from THP-1 cells or RAW264.7 cells. Our in vitro results indicate that Exo-MT can downregulate the expression of PD-L1 on macrophages while Exo-con can upregulate the expression of PD-L1 through flow cytometry and immunofluorescence analysis. In addition, Exo-con upregulates the secretion of cytokines, such as IL-6, IL-10, IL-1β, and TNF-α in macrophages. Accordingly, Exo-MT could attenuate the high expression of these inflammatory cytokines. Furthermore, in vivo experiments confirmed the results found in vitro. PD-L1 expression and cytokine secretion were lower in the Exo-MT group compared with those in the Exo-con group. Working to identify a specific mechanism, our research shows that Exo-MT decreases STAT3 activation compared to the Exo-con group. In summary, we found exosomes from melatonin treated hepatocellularcarcinoma cells alters the immunosupression status through STAT3 pathway in macrophages. Our study may provide a new avenue to investigate the mechanisms of melatonin in regulating an immunosuppressive status.

CIMAvax-EGF: A New Therapeutic Vaccine for Advanced Non-Small Cell Lung Cancer Patients

Lung cancer is the common fatal illness with the highest incidence and mortality globally. Epidermal growth factor receptor overexpression by tumor cells is associated with uncontrolled proliferation, angiogenesis, anti-apoptotic signals, metastization, and invasiveness. CIMAvax-EGF vaccine consists of a chemical conjugate of the EGF with the P64 protein derived from the Meningitis B bacteria and Montanide ISA 51, as adjuvant. The vaccine is projected to induce antibodies against EGF that results in EGF withdrawal. CIMAvax-EGF demonstrated to be safe and immunogenic in advanced non-small cell lung cancer (NSCLC) patients. The efficacy study was an open-label, multicentric Phase III clinical trial, which enrolled 405 advanced NSCLC patients. Patients with proven stage IIIB/IV NSCLC, who had completed four to six cycles of chemotherapy (CTP) were randomized to receive CIMAvax-EGF or best supportive care. CIMAvax-EGF resulted in a significantly larger overall survival in patients receiving at least four doses. High EGF concentration at baseline was a good predictive biomarker of the vaccine activity and a poor prognostic biomarker for the non-treated population. The proportion of CD8+CD28- cells, CD4 cells, and the CD4/CD8 ratio after first-line CTP was also associated with CIMAvax-EGF clinical benefit. After completing the Phase III, a Phase IV trial was done where the vaccine was administered in primary care units. Administering the vaccine at primary care institutions granted better access and treatment compliance. Safety was confirmed. Several clinical trials are currently ongoing to validate EGF as a predictive biomarker of CIMAvax-EGF efficacy.

Immunotherapy with Dendritic Cells Modified with Tumor-Associated Antigen Gene Demonstrates Enhanced Antitumor Effect Against Lung Cancer

BACKGROUND: Immunotherapy using dendritic cell (DC) vaccine has the potential to overcome the bottleneck of cancer therapy. METHODS: We engineered Lewis lung cancer cells (LLCs) and bone marrow–derived DCs to express tumor-associated antigen (TAA) ovalbumin (OVA) via lentiviral vector plasmid encoding OVA gene. We then tested the antitumor effect of modified DCs both in vitro and in vivo. RESULTS: The results demonstrated that in vitro modified DCs could dramatically enhance T-cell proliferation (P < .01) and killing of LLCs than control groups (P < .05). Moreover, modified DCs could reduce tumor size and prolong the survival of LLC tumor-bearing mice than control groups (P < .01 and P < .01, respectively). Mechanistically, modified DCs demonstrated enhanced homing to T-cell–rich compartments and triggered more naive T cells to become cytotoxic T lymphocytes, which exhibited significant infiltration into the tumors. Interestingly, modified DCs also markedly reduced tumor cells harboring stem cell markers in mice (P < .05), suggesting the potential role on cancer stem-like cells. CONCLUSION: These findings suggested that DCs bioengineered with TAA could enhance antitumor effect and therefore represent a novel anticancer strategy that is worth further exploration.

Tumor-targeted delivery of sunitinib base enhances vaccine therapy for advanced melanoma by remodeling the tumor microenvironment

Development of an effective treatment against advanced tumors remains a major challenge for cancer immunotherapy. We have previously developed a potent mannose-modified lipid calcium phosphate (LCP) nanoparticle (NP)-based Trp2 vaccine for melanoma therapy, but because this vaccine can induce a potent anti-tumor immune response only during the early stages of melanoma, poor tumor growth inhibition has been observed in more advanced melanoma models, likely due to the development of an immune-suppressive tumor microenvironment (TME). To effectively treat this aggressive tumor, a multi-target receptor tyrosine kinase inhibitor, sunitinib base, was efficiently encapsulated into a targeted polymeric micelle nano-delivery system (SUNb-PM), working in a synergistic manner with vaccine therapy in an advanced mouse melanoma model. SUNb-PM not only increased cytotoxic T-cell infiltration and decreased the number and percentage of MDSCs and Tregs in the TME, but also induced a shift in cytokine expression from Th2 to Th1 type while remodeling the tumor-associated fibroblasts, collagen, and blood vessels in the tumor. Additionally, inhibition of the Stat3 and AKT signaling pathways by SUNb-PM may induce tumor cell apoptosis or decrease tumor immune evasion. Our findings indicated that targeted delivery of a tyrosine kinase inhibitor to tumors can be used in a novel synergistic way to enhance the therapeutic efficacy of existing immune-based therapies for advanced melanoma.

The role of IL-29 in immunity and cancer

Interleukin-29 (IL-29) is a new member of the recently discovered interferon λ (IFNλ) family. It is produced predominantly by maturing dendritic cells and macrophages. It has been implicated in numerous immunological responses and has shown antiviral activity similar to the Type I interferons, although its target cell population is more limited than the Type I interferons. In recent years, the role of IL-29 in the pathogenesis of various cancers has also been extensively studied. In this review, we will discuss the recent advances of IL-29 in immunological processes and the pathogenesis of various cancer.

The Utilization of the Immune System in Lung Cancer Treatment: Beyond Chemotherapy

Lung cancer is ranked first worldwide as one of the main cancers in terms of prevalence and mortality rate. The development of effective treatment strategies against lung cancer is therefore of paramount importance. Traditionally, chemotherapy was employed in the treatment of various cancers. However, the non-specific nature of the actions of chemotherapeutic drugs and the potential for tumors to develop resistance to these drugs may render chemotherapy a less favorable option for cancer treatment. Immunotherapy provides an alternative strategy for this purpose. It involves the utilization of the immune system and the immune effector cells to elicit an immune response to the tumors, thereby eliminating them. Strategies include the administration of pro-inflammatory cytokines for immune stimulation, the removal of immunological checkpoints using monoclonal antibodies, and the use of cancer vaccines to enhance immunity against tumors. This article summarizes the above strategies, highlights the reasons why immunotherapy is superior to chemotherapy for the purpose of tumor removal, and reviews the recent clinical studies comparing the clinical outcomes of patients undergoing immunotherapy and chemotherapy. The article also describes advances in immunotherapeutic strategies for the treatment of lung cancer.

Recent advances in understanding hepatitis C

The past decade has seen tremendous progress in understanding hepatitis C virus (HCV) biology and its related disease, hepatitis C. Major advances in characterizing viral replication have led to the development of direct-acting anti-viral therapies that have considerably improved patient treatment outcome and can even cure chronic infection. However, the high cost of these treatments, their low barrier to viral resistance, and their inability to prevent HCV-induced liver cancer, along with the absence of an effective HCV vaccine, all underscore the need for continued efforts to understand the biology of this virus. Moreover, beyond informing therapies, enhanced knowledge of HCV biology is itself extremely valuable for understanding the biology of related viruses, such as dengue virus, which is becoming a growing global health concern. Major advances have been realized over the last few years in HCV biology and pathogenesis, such as the discovery of the envelope glycoprotein E2 core structure, the generation of the first mouse model with inheritable susceptibility to HCV, and the characterization of virus-host interactions that regulate viral replication or innate immunity. Here, we review the recent findings that have significantly advanced our understanding of HCV and highlight the major challenges that remain.

Macrophages Reprogrammed In Vitro Towards the M1 Phenotype and Activated with LPS Extend Lifespan of Mice with Ehrlich Ascites Carcinoma

Background

The majority of tumors trigger macrophage reprogramming from an anti-tumor M1 phenotype towards a pro-tumor M2 phenotype. The M2 phenotype promotes tumor growth. We hypothesized that increasing the number of M1 macrophages in a tumor would limit carcinogenesis and extend the lifespan of the tumor host. The aim of this study was to verify this hypothesis in Ehrlich ascites carcinoma (EAC). The objectives were to evaluate effects of 1) EAC on a macrophage phenotype and NO-producing macrophage activity in vivo; 2) ascitic fluid from mice with EAC on a macrophage phenotype and NO-producing macrophage activity in vitro; and 3) in vitro reprogrammed M1 macrophages on lifespan of mice with EAC.

Material/Methods

The study was conducted using C57BL/6J mice.

Results

Concentration of nitrite, a stable NO metabolite and an index of NO production, was measured spectrophotometrically. Shifts of macrophage phenotype were assessed by changes in NO production as well as by amounts of CD80, a marker of M1 phenotype, and CD206, a marker of M2 phenotype. The CD markers were measured by flow cytometry. Macrophages were reprogrammed towards the M1 phenotype using two reprogramming factors: 0% FBS and 20 ng/ml IFN-γ. The study results showed that 1) EAC inhibited the macrophage NO production in vivo and reprogrammed macrophages towards the M2 phenotype; 2) ascitic fluid of mice with EAC inhibited the macrophage NO production in vitro and reprogrammed macrophages towards the M2 phenotype; and 3) injection of in vitro reprogrammed M1 macrophages into mice with EAC significantly increased the lifespan of mice.

Conclusions

These findings suggest that promising biotechnologies for restriction of tumor growth could be developed based on the in vitro macrophage reprogramming.

The La-Related Proteins, a Family with Connections to Cancer

The evolutionarily-conserved La-related protein (LARP) family currently comprises Genuine La, LARP1, LARP1b, LARP4, LARP4b, LARP6 and LARP7. Emerging evidence suggests each LARP has a distinct role in transcription and/or mRNA translation that is attributable to subtle sequence variations within their La modules and specific C-terminal domains. As emerging research uncovers the function of each LARP, it is evident that La, LARP1, LARP6, LARP7 and possibly LARP4a and 4b are dysregulated in cancer. Of these, LARP1 is the first to be demonstrated to drive oncogenesis. Here, we review the role of each LARP and the evidence linking it to malignancy. We discuss a future strategy of targeting members of this protein family as cancer therapy.