Vaccines versus immunotherapy: overview of approaches in deciding between options

Immunotherapy as a Therapeutic Strategy for Gastrointestinal Cancer-Current Treatment Options and Future Perspectives

Gastrointestinal (GI) cancer constitutes a highly lethal entity among malignancies in the last decades and is still a major challenge for cancer therapeutic options. Despite the current combinational treatment strategies, including chemotherapy, surgery, radiotherapy, and targeted therapies, the survival rates remain notably low for patients with advanced disease. A better knowledge of the molecular mechanisms that influence tumor progression and the development of optimal therapeutic strategies for GI malignancies are urgently needed. Currently, the development and the assessment of the efficacy of immunotherapeutic agents in GI cancer are in the spotlight of several clinical trials. Thus, several new modalities and combinational treatments with other anti-neoplastic agents have been identified and evaluated for their efficiency in cancer management, including immune checkpoint inhibitors, adoptive cell transfer, chimeric antigen receptor (CAR)-T cell therapy, cancer vaccines, and/or combinations thereof. Understanding the interrelation among the tumor microenvironment, cancer progression, and immune resistance is pivotal for the optimal therapeutic management of all gastrointestinal solid tumors. This review will shed light on the recent advances and future directions of immunotherapy for malignant tumors of the GI system.

Cellular Immunotherapy and the Lung

The new era of cellular immunotherapies has provided state-of-the-art and efficient strategies for the prevention and treatment of cancer and infectious diseases. Cellular immunotherapies are at the forefront of innovative medical care, including adoptive T cell therapies, cancer vaccines, NK cell therapies, and immune checkpoint inhibitors. The focus of this review is on cellular immunotherapies and their application in the lung, as respiratory diseases remain one of the main causes of death worldwide. The ongoing global pandemic has shed a new light on respiratory viruses, with a key area of concern being how to combat and control their infections. The focus of cellular immunotherapies has largely been on treating cancer and has had major successes in the past few years. However, recent preclinical and clinical studies using these immunotherapies for respiratory viral infections demonstrate promising potential. Therefore, in this review we explore the use of multiple cellular immunotherapies in treating viral respiratory infections, along with investigating several routes of administration with an emphasis on inhaled immunotherapies.

Clinical translation of immunomodulatory therapeutics

Immunomodulatory therapeutics represent a unique class of drug products that have tremendous potential to rebalance malfunctioning immune systems and are quickly becoming one of the fastest-growing areas in the pharmaceutical industry. For these drugs to become mainstream medicines, they must provide greater therapeutic benefit than the currently used treatments without causing severe toxicities. Immunomodulators, cell-based therapies, antibodies, and viral therapies have all achieved varying amounts of success in the treatment of cancers and/or autoimmune diseases. However, many challenges related to precision dosing, off-target effects, and manufacturing hurdles will need to be addressed before we see widespread adoption of these therapies in the clinic. This review provides a perspective on the progress of immunostimulatory and immunosuppressive therapies to date and discusses the opportunities and challenges for clinical translation of the next generation of immunomodulatory therapeutics.

Complete Clinical Remission of Stage IV Triple-Negative Breast Cancer Lung Metastasis Administering Low-Dose Immune Checkpoint Blockade in Combination With Hyperthermia and Interleukin-2

The prognosis of triple-negative breast cancer with metastases after chemotherapy remains dismal. We report the case of a 50-year-old female with first disease recurrence at the axillary lymph node and, later on, bilateral pulmonary metastases with severe shortness of breath. The patient received low-dose immune checkpoint blockade (concurrent nivolumab and ipilimumab) weekly over 3 weeks with regional hyperthermia 3 times a week, followed by systemic fever-range hyperthermia induced by interleukin-2 for 5 days. She went into complete remission of her pulmonary metastases with transient WHO I-II diarrhea and skin rash. The patient remained alive for 27 months after the start of treatment, with recurrence of metastases as a sternal mass, and up to 3 cm pleural metastases. This exceptional response should instigate further research efforts with this protocol, which consists only of approved drugs and treatments.

Clinical Response Rates From Interleukin-2 Therapy for Metastatic Melanoma Over 30 Years' Experience: A Meta-Analysis of 3312 Patients

Interleukin-2 (IL-2), initially used in 1986, can induce clinical regression-complete responses (CR) and partial responses (PR) of metastatic malignant melanoma. IL-2 has been used alone or in combination, and in different dosage schedules, as an immunotherapeutic agent for melanoma treatment. This meta-analysis aimed to document and evaluate the spectrum of reported clinical response rates from the combined experience of almost 30 years of IL-2 clinical usage. Clinical trials using IL-2 for metastatic melanoma therapy that reported: dosage, combinations, study details, definitions and clinical CR, PR, and overall response (OR) rates were included. A meta-analysis was conducted using the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. In total, 34 studies met inclusion criteria, with 41 separate treatment arms. For all IL-2 treatment modalities collectively, the CR rate was 4.0% [95% confidence interval (CI), 2.8-5.3], PR 12.5% (95% CI, 10.1-15.0), and OR 19.7% (95% CI, 15.9-23.5). CR pre-1994 was 2.7% versus 6.1% post-1994. High and intermediate-IL-2 dosage showed no CR difference, while low-dose IL-2 showed a nonstatistical trend toward an increased CR rate. The highest CR rate resulted from IL-2 combined with vaccine at 5.0%. The meta-analysis showed that IL-2 immunotherapy for advanced metastatic melanoma delivered a CR rate of 4% (range, 0-23%) across nearly 30 years of clinical studies, with gradual improvement over time. The significance is that, contrary to popular belief, the data demonstrated that CR rates were similar for intermediate versus high-IL-2 dosing.

An efficient and scalable synthesis of potent TLR2 agonistic PAM2CSK4

Diacylated PAM₂CSK₄, a highly expensive lipopeptide with desirable aqueous solubility and a broad spectrum of cytokine/chemokine induction is a most potent dual (human and murine) Toll-Like Receptor-2 (TLR2) agonist.

hrHPV E5 oncoprotein: immune evasion and related immunotherapies

The immune response is a key factor in the fight against HPV infection and related cancers, and thus, HPV is able to promote immune evasion through the expression of oncogenes. In particular, the E5 oncogene is responsible for modulation of several immune mechanisms, including antigen presentation and inflammatory pathways. Moreover, E5 was suggested as a promising therapeutic target, since there is still no effective medical therapy for the treatment of HPV-related pre-neoplasia and cancer. Indeed, several studies have shown good prospective for E5 immunotherapy, suggesting that it could be applied for the treatment of pre-cancerous lesions. Thus, insofar as the majority of cervical, oropharyngeal and anal cancers are caused by high-risk HPV (hrHPV), mainly by HPV16, the aim of this review is to discuss the immune pathways interfered by E5 oncoprotein of hrHPV highlighting the various aspects of the potential immunotherapeutic approaches.

Immunological effects of different types of synthetic CpG oligodeoxynucleotides on porcine cells

The agonists of toll-like receptor 9, synthetic oligodeoxynucleotides (ODNs) containing CpG sequences, stimulate innate and adaptive immune responses in humans and a variety of animal species.

Anti-PD-1 increases the clonality and activity of tumor infiltrating antigen specific T cells induced by a potent immune therapy consisting of vaccine and metronomic cyclophosphamide

BACKGROUND

Future cancer immunotherapies will combine multiple treatments to generate functional immune responses to cancer antigens through synergistic, multi-modal mechanisms. In this study we explored the combination of three distinct immunotherapies: a class I restricted peptide-based cancer vaccine, metronomic cyclophosphamide (mCPA) and anti-PD-1 treatment in a murine tumor model expressing HPV16 E7 (C3).

METHODS

Mice were implanted with C3 tumors subcutaneously. Tumor bearing mice were treated with mCPA (20 mg/kg/day PO) for seven continuous days on alternating weeks, vaccinated with HPV16 E749-57 peptide antigen formulated in the DepoVax (DPX) adjuvanting platform every second week, and administered anti-PD-1 (200 μg/dose IP) after each vaccination. Efficacy was measured by following tumor growth and survival. Immunogenicity was measured by IFN-γ ELISpot of spleen, vaccine draining lymph nodes and tumor draining lymph nodes. Tumor infiltration was measured by flow cytometry for CD8α+ peptide-specific T cells and RT-qPCR for cytotoxic proteins. The clonality of tumor infiltrating T cells was measured by TCRβ sequencing using genomic DNA.

RESULTS

Untreated C3 tumors had low expression of PD-L1 in vivo and anti-PD-1 therapy alone provided no protection from tumor growth. Treatment with DPX/mCPA could delay tumor growth, and tri-therapy with DPX/mCPA/anti-PD-1 provided long-term control of tumors. We found that treatment with DPX/mCPA/anti-PD-1 enhanced systemic antigen-specific immune responses detected in the spleen as determined by IFN-γ ELISpot compared to those in the DPX/mCPA group, but immune responses in tumor-draining lymph nodes were not increased. Although no increases in antigen-specific CD8α+ TILs could be detected, there was a trend for increased expression of cytotoxic genes within the tumor microenvironment as well as an increase in clonality in mice treated with DPX/mCPA/anti-PD-1 compared to those with anti-PD-1 alone or DPX/mCPA. Using a library of antigen-specific CD8α+ T cell clones, we found that antigen-specific clones were more frequently expanded in the DPX/mCPA/anti-PD-1 treated group.

CONCLUSIONS

These results demonstrate how the efficacy of anti-PD-1 may be improved by combination with a potent and targeted T cell activating immune therapy.