Combined Checkpoint Inhibition and Chemotherapy: New Era of 1st-Line Treatment for Non-Small-Cell Lung Cancer

Cisplatin in the era of PARP inhibitors and immunotherapy

Platinum compounds such as cisplatin, carboplatin and oxaliplatin are widely used in chemotherapy. Cisplatin induces cytotoxic DNA damage that blocks DNA replication and gene transcription, leading to arrest of cell proliferation. Although platinum therapy alone is effective against many tumors, cancer cells can adapt to the treatment and gain resistance. The mechanisms for cisplatin resistance are complex, including low DNA damage formation, high DNA repair capacity, changes in apoptosis signaling pathways, rewired cell metabolisms, and others. Drug resistance compromises the clinical efficacy and calls for new strategies by combining cisplatin with other therapies. Exciting progress in cancer treatment, particularly development of poly (ADP-ribose) polymerase (PARP) inhibitors and immune checkpoint inhibitors, opened a new chapter to combine cisplatin with these new cancer therapies. In this Review, we discuss how platinum synergizes with PARP inhibitors and immunotherapy to bring new hope to cancer patients.

Multi-omics analysis of macrophage-associated receptor and ligand reveals a strong prognostic signature and subtypes in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a significant contributor to morbidity and mortality worldwide. The interaction between receptors and ligands is the primary mode of intercellular signaling and plays a vital role in the progression of HCC. This study aimed to identify the macrophage-related receptor ligand marker genes associated with HCC and further explored the molecular immune mechanisms attributed to altered biomarkers. Single-cell RNA sequencing data containing primary and recurrent samples were downloaded from the China National GeneBank. Cell types were first identified to explore differences between immune cells from different sample sources. CellChat analysis was used to infer and analyze intercellular communication networks quantitatively. Three molecular subtypes were constructed based on the screened twenty macrophage-associated receptor ligand genes. Bulk RNA-Seq data were downloaded from The Cancer Genome Atlas and Gene Expression Omnibus databases. After the screening, the minor absolute shrinkage and selection operator (LASSO) regression model was employed to identify key markers. After collecting peripheral blood and clinical information from patients, an enzyme-linked immunosorbent assay (ELISA) was used to detect the correlation between key markers and IL-10, one of the macrophage markers. After developing a new HCC risk adjustment model and conducting analysis, it was found that there were significant differences in immune status and gene mutations between the high-risk and low-risk groups of patients based on macrophage-associated receptor and ligand genes. This study identified SPP1, ANGPT2, and NCL as key biological targets for HCC. The drug-gene interaction network analysis identified wortmannin, ribavirin, and tarnafloxin as potential therapeutic drugs for the three key markers. In a clinical cohort study, patients with immune checkpoint inhibitor (ICI) resistance had significantly higher expression levels of OPN, ANGPT2, NCL, and IL-10 than patients with ICI-responsiveness. These three key markers were positively correlated with the expression level of IL-10. The signature based on macrophage-associated receptor and ligand genes can accurately predict the prognosis of patients with HCC and the sensitivity to immunotherapy. These results may help guide the development of targeted prevention and personalized treatment of HCC.

Nintedanib in Combination With Chemotherapy in the Treatment of Non-small Cell Lung Cancer: A Systematic Review and Meta-Analysis

Lung cancer remains a major global health challenge, contributing to substantial morbidity and mortality rates. Nintedanib, a tyrosine kinase inhibitor, has demonstrated potential as a treatment for lung cancer. We aim to evaluate nintedanib's efficacy in treating patients with non-small cell lung cancer (NSCLC), depending on the available evidence. Our search for relevant articles was conducted on PubMed, Cochrane Library, Scopus, and Web of Science for randomized controlled trials (RCTs) that involved adult patients with NSCLC up to August 15, 2023. These trials compared the combination of nintedanib and chemotherapy to either placebo plus chemotherapy or chemotherapy alone. Our main outcomes include progression-free survival (PFS) and overall survival (OS). We utilized the Review Manager Software V.5.4 (The Cochrane Collaboration) to analyze all relevant data. Three identified trials, which included 2270 patients, fulfilled the inclusion criteria. Our analysis showed significantly improved PFS (hazard ratio (HR) = 0.79; 95% confidence interval (CI) 0.71-0.88, P < 0.0001) in patients receiving nintedanib compared to placebo. However, OS was not statistically significant (HR = 0.96; 95% CI 0.88-1.05, P = 0.35). In conclusion, a combination of nintedanib and chemotherapy in treating patients with NSCLC was associated with improved PFS than chemotherapy alone but not with improved OS. Further clinical trials assessing nintedanib in the setting of NSCLC are necessary before any further recommendations can be made.

Retrospective evaluation of safety and effectiveness of same-day pegfilgrastim in patients with lung cancer

Aim: To determine the incidence of chemotherapy-induced febrile neutropenia (FN) and related outcomes after same-day pegfilgrastim in lung cancer. Materials & methods: This single-center, retrospective study evaluated electronic health records of patients with lung cancer treated between 2013-2018. The main end points were incidence of FN and grade 3/4 neutropenia after the first and across all chemotherapy cycles. Results: A total of 114 patients received same-day pegfilgrastim in 384 cycles. The incidence of FN and grade 3/4 neutropenia was 2.3 and 25% after the first chemotherapy cycle and 1.6 and 10.4% across all cycles, respectively. Conclusion: Same-day prophylactic pegfilgrastim in patients with lung cancer may be a suitable option, owing to its low incidence of FN and related outcomes.

Chemotherapy plus single/double immunotherapy in the treatment of non-oncogene addicted advanced non-small cell lung cancer: where do we stand and where are we going?

INTRODUCTION

: Chemo-immunotherapy combinations have revolutionized our treatment algorithm with respect to naïve advanced NSCLC, however, given the great number of developed and approved combinations, the question arises as to which combinations provide the best efficacy and safety.

AREAS COVERED

: This review assesses and discusses the available data concerning chemo-immunotherapy combinations in the treatment of naïve advanced NSCLC, as well as presenting the most promising data involving combinations currently under investigation.

EXPERT OPINION

: Pembrolizumab-containing chemo-immunotherapy combinations are associated with the most mature data available and presently represent the standard treatment in clinical practice in naïve advanced NSCLC-affected patients. The nivolumab plus ipilimumab plus short-course chemotherapy combination, more recently approved by regulatory agencies, is an appealing alternative thanks to the reduced rate of grade 3-5 TRAEs and the limited chemotherapy administration. The new chemo-immunotherapy combinations currently under investigation will help us to better identify both the best immune checkpoints to target and the most effective combinations to administer.

Immunotherapy of Ovarian Cancer with Particular Emphasis on the PD-1/PDL-1 as Target Points

Simple Summary

Ovarian cancer has remained the leading cause of death among gynecologic malignancies. The current standard of treatment, in most cases, is a combination of surgery and chemotherapy, based on platinum agents and taxanes. Despite the increasing usage of newer drug groups, such as bevacizumab and PARP inhibitors, and the expansion of patient groups for these drugs, ovarian cancer is characterized by recurrences, particularly in the form of peritoneal implants. This review focuses on immunotherapy for ovarian cancer. It considers the current state of knowledge in areas such as cancer vaccines, adoptive cell therapy, CAR-T therapy, and anti-CTLA-4 monotherapy. The paper specifically considers PD-1/PDL-1 as drug targets. Anti-PD-1/PD-L1 monotherapy, and anti-PD-1/PD-L1 immunotherapy in combination with other agents, are analyzed.

Abstract

Ovarian cancer is one of the most fatal cancers in women worldwide. Cytoreductive surgery combined with platinum-based chemotherapy has been the current first-line treatment standard. Nevertheless, ovarian cancer appears to have a high recurrence rate and mortality. Immunological processes play a significant role in tumorigenesis. The production of ligands for checkpoint receptors can be a very effective, and undesirable, immunosuppressive mechanism for cancers. The CTLA-4 protein, as well as the PD-1 receptor and its PD-L1 ligand, are among the better-known components of the control points. The aim of this paper was to review current research on immunotherapy in the treatment of ovarian cancer. The authors specifically considered immune checkpoints molecules such as PD-1/PDL-1 as targets for immunotherapy. We found that immune checkpoint-inhibitor therapy does not have an improved prognosis in ovarian cancer; although early trials showed that a combination of anti-PD-1/PD-L1 therapy with targeted therapy might have the potential to improve responses and outcomes in selected patients. However, we must wait for the final results of the trials. It seems important to identify a group of patients who could benefit significantly from treatment with immune checkpoints inhibitors. However, despite numerous trials, ICIs have not become part of routine clinical practice for the treatment of ovarian cancer.

A Phase Ib Open-Label, Multicenter Study of Inhaled DV281, a TLR9 Agonist, in Combination with Nivolumab in Patients with Advanced or Metastatic Non-small Cell Lung Cancer

PURPOSE

Although PD-(L)1 inhibitors have shown efficacy in advanced/metastatic non-small cell lung cancer (NSCLC), many patients do not respond to this treatment and more effective combinations with acceptable toxicities are needed. To assess the potential benefit of combining localized innate immune stimulation with checkpoint blockade, the TLR9 agonist DV281 was combined with nivolumab in a phase Ib study.

PATIENTS AND METHODS

Patients after one or two prior lines of systemic therapy were enrolled in a dose-escalation study with a 3+3 design. DV281 was administered via inhalation in five dose cohorts at 1 to 25 mg; nivolumab 240 mg was administered intravenously every 2 weeks. Safety, tolerability, pharmacodynamics, and response to treatment were assessed.

RESULTS

Twenty-six patients with advanced NSCLC enrolled. Baseline programmed death ligand 1 (PD-L1) expression was present in 16 patients (61.5%); 21 (80.7%) had received previous anti-PD-1/PD-L1. Thirteen patients (50%) had stable disease, nine (34.6%) had progressive disease, and four (15.4%) were not evaluable. Median duration of disease control was 124 days. Adverse events were seen in 16 patients (61.5%), mostly grade 1/2 chills, fatigue, flu-like symptoms, diarrhea, and rash; there was only one grade 3 adverse event (dyspnea). Pharmacodynamic assessment, measured by IFN- inducible gene expression, showed target engagement in all dose cohorts. Systemic pharmacodynamic responses plateaued in the 2 highest dose cohorts.

CONCLUSIONS

DV281 with nivolumab was well tolerated with target engagement observed at every dose. Pharmacodynamic advantages at doses above 10 mg were unclear. The long duration of disease control in 50% of patients suggests clinically relevant activity in this population of heavily pretreated patients.

Immunotherapy for non-small cell lung cancer (NSCLC), as a stand-alone and in combination therapy

Non-small cell lung cancer (NSCLC) is of major concern for society as it is associated with high mortality and is one of the most commonly occurring of all cancers. Due to the number of mutational variants and general heterogeneity of this type of cancer, treatment using conventional modalities has been challenging. Therefore, it is important to have improved therapeutic treatments like immunotherapy, that can specifically treat the disease while causing minimal damage to healthy tissue and additionally provide systemic immunity. Cancer vaccines are an important element of cancer immunotherapy and have been approved for treatment of a limited number of cancers, including NSCLC. This article highlights scientific evidence for several therapeutic treatment strategies for NSCLC, alone or in combination, which offers new hope for those suffering. Although cancer vaccines have had some success as a monotherapy, their potential in a combination therapy needs to be critically analyzed for future applications.

Emerging avenues in immunotherapy for the management of malignant pleural mesothelioma

BACKGROUND

The role of immunotherapy in cancer is now well-established, and therapeutic options such as checkpoint inhibitors are increasingly being approved in many cancers such as non-small cell lung cancer (NSCLC). Malignant pleural mesothelioma (MPM) is a rare orphan disease associated with prior exposure to asbestos, with a dismal prognosis. Evidence from clinical trials of checkpoint inhibitors in this rare disease, suggest that such therapies may play a role as a treatment option for a proportion of patients with this cancer.

MAIN TEXT

While the majority of studies currently focus on the established checkpoint inhibitors (CTLA4 and PD1/PDL1), there are many other potential checkpoints that could also be targeted. In this review I provide a synopsis of current clinical trials of immunotherapies in MPM, explore potential candidate new avenues that may become future targets for immunotherapy and discuss aspects of immunotherapy that may affect the clinical outcomes of such therapies in this cancer.

CONCLUSIONS

The current situation regarding checkpoint inhibitors in the management of MPM whilst encouraging, despite impressive durable responses, immune checkpoint inhibitors do not provide a long-term benefit to the majority of patients with cancer. Additional studies are therefore required to further delineate and improve our understanding of both checkpoint inhibitors and the immune system in MPM. Moreover, many new potential checkpoints have yet to be studied for their therapeutic potential in MPM. All these plus the existing checkpoint inhibitors will require the development of new biomarkers for patient stratification, response and also for predicting or monitoring the emergence of resistance to these agents in MPM patients. Other potential therapeutic avenues such CAR-T therapy or treatments like oncolytic viruses or agents that target the interferon pathway designed to recruit more immune cells to the tumor also hold great promise in this hard to treat cancer.

Drug-Like Small Molecule HSP27 Functional Inhibitor Sensitizes Lung Cancer Cells to Gefitinib or Cisplatin by Inducing Altered Cross-Linked Hsp27 Dimers

Relationships between heat shock protein 27 (HSP27) and cancer aggressiveness, metastasis, drug resistance, and poor patient outcomes in various cancer types including non-small cell lung cancer (NSCLC) were reported, and inhibition of HSP27 expression is suggested to be a possible strategy for cancer therapy. Unlike HSP90 or HSP70, HSP27 does not have an ATP-binding pocket, and no effective HSP27 inhibitors have been identified. Previously, NSCLC cancer cells were sensitized to radiation and chemotherapy when co-treated with small molecule HSP27 functional inhibitors such as zerumbone (ZER), SW15, and J2 that can induce abnormal cross-linked HSP27 dimer. In this study, cancer inhibition effects of NA49, a chromenone compound with better solubility, longer circulation time, and less toxicity than J2, were examined in combination with anticancer drugs such as cisplatin and gefitinib in NSCLC cell lines. When the cytotoxic drug cisplatin was treated in combination with NA49 in epidermal growth factor receptors (EGFRs) WT cell lines, sensitization was induced in an HSP27 expression-dependent manner. With gefitinib treatment, NA49 showed increased combination effects in both EGFR WT and Mut cell lines, also with HSP27 expression-dependent patterns. Moreover, NA49 induced sensitization in EGFR Mut cells with a secondary mutation of T790M when combined with gefitinib. Augmented tumor growth inhibition was shown with the combination of cisplatin or gefitinib and NA49 in nude mouse xenograft models. These results suggest the combination of HSP27 inhibitor NA49 and anticancer agents as a candidate for overcoming HSP27-mediated drug resistance in NSCLC patients.

Virus-Like Particle-Drug Conjugates Induce Protective, Long-lasting Adaptive Antitumor Immunity in the Absence of Specifically Targeted Tumor Antigens

This study examined the ability of a papillomavirus-like particle drug conjugate, belzupacap sarotalocan (AU-011), to eradicate subcutaneous tumors after intravenous injection and to subsequently elicit long-term antitumor immunity in the TC-1 syngeneic murine tumor model. Upon in vitro activation with near-infrared light (NIR), AU-011-mediated cell killing was proimmunogenic in nature, resulting in the release of damage-associated molecular patterns such as DNA, ATP, and HMGB-1, activation of caspase-1, and surface relocalization of calreticulin and HSP70 on killed tumor cells. A single in vivo administration of AU-011 followed by NIR caused rapid cell death, leading to long-term tumor regression in ∼50% of all animals. Within hours of treatment, calreticulin surface expression, caspase-1 activation, and depletion of immunosuppressive leukocytes were observed in tumors. Combination of AU-011 with immune-checkpoint inhibitor antibodies, anti-CTLA-4 or anti-PD-1, improved therapeutic efficacy, resulting in 70% to 100% complete response rate that was durable 100 days after treatment, with 50% to 80% of those animals displaying protection from secondary tumor rechallenge. Depletion of CD4⁺ or CD8⁺ T cells, either at the time of AU-011 treatment or secondary tumor rechallenge of tumor-free mice, indicated that both cell populations are vital to AU-011's ability to eradicate primary tumors and induce long-lasting antitumor protection. Tumor-specific CD8⁺ T-cell responses could be observed in circulating peripheral blood mononuclear cells within 3 weeks of AU-011 treatment. These data, taken together, support the conclusion that AU-011 has a direct cytotoxic effect on tumor cells and induces long-term antitumor immunity, and this activity is enhanced when combined with checkpoint inhibitor antibodies.

Association of Survival and Immune-Related Adverse Events With Anti-PD-1/PD-L1 and Anti-CTLA-4 Inhibitors, Alone or Their Combination for the Treatment of Cancer: A Systematic Review and Meta-Analysis of 13 Clinical Trials

Background

Cancer, with sustained high mortality, is a worldwide threat to public health. Despite the survival benefit over conventional therapies shown in immune checkpoint inhibitor (ICI), only a minority of patients benefit from single ICI. But combination therapy holds the promise of achieving better efficacy over monotherapy. We performed a systematic review and meta-analysis to assess the efficacy and safety of ICI-based combination therapy for cancer.

Methods

A search was conducted to retrieve relevant studies in electronic databases and major conferences. Two investigators independently performed data extraction, making a systematic data extraction, assembly, analysis and interpretation to compare the overall survival (OS), progression-free survival (PFS), overall response rate (ORR), all and high grade immune related adverse events (IRAEs) between combination therapy and monotherapy. Therefore, only the studies satisfying the criteria were included. Finally, we performed subgroup, sensitivity, and publication bias analysis to examine the heterogeneity and bias of resources.

Results

A total of 2,532 patients from thirteen studies were enrolled. Compared to ICI alone, combination therapy, with a high risk and high grade IRAEs for the majority of all, offers a better survival benefit (OS: HR: 0.86, 95% CI: 0.76 to 0.98; PFS: HR: 0.79, 95% CI: 0.69 to 0.90) and objective response (ORR: RR: 1.91, 95% CI: 1.40 to 2.60).

Conclusions

ICI-based combination therapy was confirmed as the optimum treatment for cancer, especially when using specific dosage and regimen to treat certain tumor types with no absolute demand for the detection of PD-L1 expression. Meanwhile, attention should also be paid on potential toxicity, especially the IRAEs.

Role of EIF4G1 network in non-small cell lung cancers (NSCLC) cell survival and disease progression

Although the Eukaryotic Translation Initiation Factor 4 Gamma 1 (EIF4G1) has been found overexpressed in a variety of cancers, its role in non–small cell lung cancers (NSCLC) pathogenesis especially in immunoregulatory functions, its clinical relevance and therapeutic potential remain largely unknown. By using cancer patients tissue assays, the results indicate that EIF4G1 expressional levels are much higher in NSCLC tissues than in adjacent or normal lung tissues, which are also associated with NSCLC patient survival. By using an RNA‐Sequencing based pipeline, the data show that EIF4G1 has a significant association with immune checkpoint molecules such as PD‐1/PD‐L1 in NSCLC. EIF4G1 small‐molecule inhibitors effectively repress NSCLC growth in cell culture and xenograft animal models. Protein array results identify the signature of proteins controlled by EIF4G1 in NSCLC cells, in which new candidates such as MUC1 and NRG1 are required for NSCLC survival and tumorigenesis with clinical relevance. Taken together, these results have for the first time demonstrated the immunoregulatory functions, clinical relevance and therapeutic potential of the EIF4G1 network in NSCLC, which may represent a promising and novel target to improve lung cancer treatment.

ACSL3-PAI-1 signaling axis mediates tumor-stroma cross-talk promoting pancreatic cancer progression

Pancreatic ductal adenocarcinoma (PDAC) is characterized by marked fibrosis and low immunogenicity, features that are linked to treatment resistance and poor clinical outcomes. Therefore, understanding how PDAC regulates the desmoplastic and immune stromal components is of great clinical importance. We found that acyl-CoA synthetase long-chain 3 (ACSL3) is up-regulated in PDAC and correlates with increased fibrosis. Our in vivo results show that Acsl3 knockout hinders PDAC progression, markedly reduces tumor fibrosis and tumor-infiltrating immunosuppressive cells, and increases cytotoxic T cell infiltration. This effect is, at least in part, due to decreased plasminogen activator inhibitor-1 (PAI-1) secretion from tumor cells. Accordingly, PAI-1 expression in PDAC positively correlates with markers of fibrosis and immunosuppression and predicts poor patient survival. We found that PAI-1 pharmacological inhibition strongly enhances chemo- and immunotherapeutic response against PDAC, increasing survival of mice. Thus, our results unveil ACSL3-PAI-1 signaling as a requirement for PDAC progression with druggable attributes.

Remarkable response to combined immunochemotherapy in patients with metastatic triple-negative breast cancer

Background: Progress in immunotherapy (IT) has shifted treatment paradigms for multiple malignancies. In March 2019, the combination of nab-paclitaxel and atezolizumab was approved by the US FDA for patients with PD-L1 positive metastatic triple-negative breast cancer based on positive results of the Impassion130 trial. Although numerous studies have examined the prognostic role of PD-L1, the value of this test remains controversial. Results: Here, we presented the cases of three heavily pretreated women with metastatic triple-negative breast cancer who exhibited remarkable responses to combined IT and chemotherapy despite undetectable PD-L1. Conclusion: In our opinion, the current FDA-approved assessment for PD-L1 expression is a reasonable tool for deciding whether to start IT. However, because this approach has many limitations, patients with undetectable PD-L1 expression should still be considered for IT.

Resistance to chemoimmunotherapy in non-small-cell lung cancer

Recent clinical trials evaluating the combination of chemotherapy with immune checkpoint inhibition for the primary treatment of lung cancer showed increased progression-free and overall survival compared with chemotherapy alone. However, the combination of these two modalities is less than additive and the mechanisms of resistance to this therapeutic intervention are discussed here. So far, the conventional biomarkers for immunotherapy, namely programmed death-ligand 1 expression or tumor mutational burden are poor predictors of the efficacy of immunochemotherapy, and the optimal sequence of chemotherapy and immunotherapy has yet to be defined.

Combined Atezolizumab and Chemotherapy for a Patient With Double Primary Cancers

BACKGROUND

Immune checkpoint inhibitors are indicated for non-small cell lung cancer (NSCLC) and head and neck cancer, and combined treatment of immune checkpoint inhibitor and chemotherapy has recently been carried out in patients with NSCLC. However, there is no established standard therapy for synchronous locally advanced or metastatic cancers of lung and nasopharynx.

CASE REPORT

We report a case of a metastatic lung adenocarcinoma and locally advanced epipharyngeal carcinoma successfully treated with chemotherapy and immune checkpoint inhibitor, paclitaxel, carboplatin, bevacizumab and atezolizumab. The tumor proportion score of programmed death ligand 1 was 5-10% and 70-80% for metastatic lung adenocarcinoma and locally advanced epipharyngeal carcinoma, respectively. Shrinkage of both carcinomas was confirmed, and the treatment effect was judged to be a partial response.

CONCLUSION

This was the first patient who was treated with this combination treatment. Our clinical experience suggests that this treatment could be one of the options for patients with these advanced cancers and an overall good clinical condition.

The miRNA-149-5p/MyD88 axis is responsible for ursolic acid-mediated attenuation of the stemness and chemoresistance of non-small cell lung cancer cells

Although the inhibitory roles of ursolic acid (UA) have been established in various tumors, its effects on the stemness of non-small cell lung cancer (NSCLC) cells are still unclear. Here, we constructed NSCLC cells with paclitaxel resistance (A549-PR) and showed that A549-PR exhibited a remarkably stronger stemness than the parental A549 cells, which is evident by the increase of spheroid formation capacity, stemness marker expression, and ALDH1 activity. Additionally, UA significantly reduced the stemness and paclitaxel resistance of A549-PR cells. Mechanistic investigations revealed that UA inhibited the miR-149-5p/MyD88 signaling, which is responsible for UA-mediated effects on the stemness of A549-PR cells. Notably, miR-149-5p/MyD88 axis promoted the stemness of A549 cells, while inhibition of this axis attenuated the stemness of A549-PR cells. Therefore, these results suggest that UA could attenuate the stemness and chemoresistance of NSCLC cells through targeting miR-149-5p/MyD88 axis.

Opportunities for Conventional and in Situ Cancer Vaccine Strategies and Combination with Immunotherapy for Gastrointestinal Cancers, A Review

Survival of gastrointestinal cancer remains dismal, especially for metastasized disease. For various cancers, especially melanoma and lung cancer, immunotherapy has been proven to confer survival benefits, but results for gastrointestinal cancer have been disappointing. Hence, there is substantial interest in exploring the usefulness of adaptive immune system education with respect to anti-cancer responses though vaccination. Encouragingly, even fairly non-specific approaches to vaccination and immune system stimulation, involving for instance influenza vaccines, have shown promising results, eliciting hopes that selection of specific antigens for vaccination may prove useful for at least a subset of gastrointestinal cancers. It is widely recognized that immune recognition and initiation of responses are hampered by a lack of T cell help, or by suppressive cancer-associated factors. In this review we will discuss the hurdles that limit efficacy of conventional cancer therapeutic vaccination methods (e.g., peptide vaccines, dendritic cell vaccination). In addition, we will outline other forms of treatment (e.g., radiotherapy, chemotherapy, oncolytic viruses) that also cause the release of antigens through immunogenic tumor cell death and can thus be considered unconventional vaccination methods (i.e., in situ vaccination). Finally, we focus on the potential additive value that vaccination strategies may have for improving the effect immunotherapy. Overall, a picture will emerge that although the field has made substantial progress, successful immunotherapy through the combination with cancer antigen vaccination, including that for gastrointestinal cancers, is still in its infancy, prompting further intensification of the research effort in this respect.

HDAC Inhibitor, CG-745, Enhances the Anti-Cancer Effect of Anti-PD-1 Immune Checkpoint Inhibitor by Modulation of the Immune Microenvironment

Histone deacetylase inhibitors (HDACis) are well-known epigenetic regulators with therapeutic potential in various diseases. Recent studies have shown that HDACis are involved in immune-mediated anti-cancer effects and may modulate the activity of immunotherapy agents. CG-745, a histone deacetylase inhibitor, has shown anti-cancer effects in pancreatic cancer, colorectal cancer, and non-small cell lung cancer. However, the exact role of CG-745 within the immune system is largely unknown. In this study, we have shown that CG-745 induces microenvironment changes promoting anti-cancer effect of anti-PD-1 antibody in syngeneic mouse models. Specifically, CG-745 induces or extends IL-2 and IFN-γ expression with or without additional stimulation, and increases proliferation of cytotoxic T cells and NK cells, while inhibiting proliferation of regulatory T cells. The analysis of immune cell distribution in the tumor microenvironment and spleen reveals that CG-745 suppresses M2 macrophage polarization and decreases the myeloid-derived suppressor cells. Recent advances in immunotherapy highlight the anti-cancer effects of immune checkpoint inhibitor despite a relatively limited clinical benefit in the subset of patients. Our results indicate that CG-745 enables the synergistic effects of the immune checkpoint inhibitor combination therapy in various cancers by suppressing tumor microenvironment.

Safety and Efficacy of PD-1 Inhibitors Plus Chemotherapy in Advanced Soft Tissue Sarcomas: A Retrospective Study

Purpose

Programmed cell death 1 (PD-1) inhibitors are ineffective as monotherapy for the treatment of soft tissue sarcomas (STS). However, increasing evidence shows that the combination of PD-1 inhibitors and chemotherapy is efficacious and safe for many types of malignancies, including STS. This study aimed to assess the safety and efficacy of doxorubicin chemotherapy plus PD-1 inhibitor in the treatment of metastatic STS.

Patients and Methods

We retrospectively reviewed 21 patients with metastatic STS who received doxorubicin chemotherapy plus a PD-1 inhibitor between November 2017 and October 2018.

Results

The objective response rate was 47.6%, the disease control rate was 71.40%, and the median progression-free survival was 6 months (95% CI, 2–8 months). The average change in target lesion diameter from baseline was −25.15 ± 41.61. Majority of the patients experienced grade 1/2 adverse events (AEs), the grade 3/4 AEs were few. The most common grade 3/4 AEs were as follows: leukopenia (23.8%) and anemia (19.0%). Immune-related AEs were common and included hypothyroidism (14.3%) and pneumonitiss (9.5%). No drug related deaths occurred.

Conclusion

This study provides preliminary evidence that the combination of doxorubicin chemotherapy and PD-1 inhibitor for advanced STS is safe and effective. We plan to conduct randomized clinical trials to confirm and characterize the activity of the chemotherapy-immunotherapy combinations in the treatment of sarcomas.

Targeting Negative and Positive Immune Checkpoints with Monoclonal Antibodies in Therapy of Cancer

The immune checkpoints are regulatory molecules that maintain immune homeostasis in physiological conditions. By sending T cells a series of co-stimulatory or co-inhibitory signals via receptors, immune checkpoints can both protect healthy tissues from adaptive immune response and activate lymphocytes to remove pathogens effectively. However, due to their mode of action, suppressive immune checkpoints may serve as unwanted protection for cancer cells. To restore the functioning of the immune system and make the patient’s immune cells able to recognize and destroy tumors, monoclonal antibodies are broadly used in cancer immunotherapy to block the suppressive or to stimulate the positive immune checkpoints. In this review, we aim to present the current state of application of monoclonal antibodies in clinics, used either as single agents or in a combined treatment. We discuss the limitations of these therapies and possible problem-solving with combined treatment approaches involving both non-biological and biological agents. We also highlight the most promising strategies based on the use of monoclonal or bispecific antibodies targeted on immune checkpoints other than currently implemented in clinics.

The effects and mechanisms of a biosynthetic ginsenoside 3β,12β-Di-O-Glc-PPD on non-small cell lung cancer

Background

A biosynthetic ginsenoside, 3-O-β-D-glucopyranosyl-12-O-β-D-glucopyranosyl-dammar-24-ene-3β, 12β, 20S-triol (C₃C₁₂PPD), showed antitumor activity against many tumor cells in vitro, especially had better anti-lung cancer activity than Rg3 in vitro and in vivo. However, the effects and molecular mechanisms of C₃C₁₂PPD on non-small cell lung cancer (NSCLC) remain unclear. According to previous studies, we hypothesized ginsenoside C₃C₁₂PPD could inhibit the tumor growth of NSCLC by targeting proliferation, migration and angiogenesis.

Methods

A thiazolyl blue tetrazolium bromide assay (MTT) was performed to evaluate cell viability. Additionally, Transwell and tube formation assays were conducted to analyze cell migration and angiogenesis. The Lewis and A549 tumor xenograft experiments were also performed to investigate the effects of C₃C₁₂PPD on tumor growth in vivo, Western blotting and IHC assay were performed to analyze protein expression.

Results

C₃C₁₂PPD could effectively inhibit the proliferation and migration of lung cancer cells, and tube formation of EA.hy926 cell. Ginsenoside C₃C₁₂PPD suppressed Lewis and A549 tumor growth in vivo without obvious side effects on body weight and the hematology index. In addition, the Western blot analysis revealed that the effects of C₃C₁₂PPD on lung cancer were mediated by inhibiting Raf/MEK/ERK, AKT/mTOR and AKT/GSK-3β/β-Catenin signaling pathways. Finally, C₃C₁₂PPD could significantly inhibit the proliferation index and vessel number in Lewis xenograft tumors analyzed by IHC.

Conclusion

The results of the present study suggest that ginsenoside C₃C₁₂PPD may serve as a potential therapeutic candidate compound against NSCLC.

A Review of the Role of Wnt in Cancer Immunomodulation

Alterations in the Wnt signaling pathway are associated with the advancement of cancers; however, the exact mechanisms responsible remain largely unknown. It has recently been established that heightened intratumoral Wnt signaling correlates with tumor immunomodulation and immune suppression, which likely contribute to the decreased efficacy of multiple cancer therapeutics. Here, we review available literature pertaining to connections between Wnt pathway activation in the tumor microenvironment and local immunomodulation. We focus specifically on preclinical and clinical data supporting the hypothesis that strategies targeting Wnt signaling could act as adjuncts for cancer therapy, either in combination with chemotherapy or immunotherapy, in a variety of tumor types.