Mechanism of action of immunotherapy

Immunotherapy in Stage III-IV Colon Cancer: A Propensity Score-Matched Analysis of the National Cancer Database

SUMMARY

Immunotherapy for the systemic treatment of cancer offers new treatment possibilities for advanced malignancies. Despite promising initial results, evidence on efficacy of immunotherapy for colon cancer is lacking. Thus, we aimed to assess short-term and long-term outcomes of immunotherapy in patients with advanced colon cancer. A US National Cancer Database was searched for patients with stage III-IV colonic adenocarcinoma between 2010 and 2019. Propensity score matching was used to classify the cohort into 2 groups: patients who received immunotherapy and controls. Main outcome measures were primary outcome was overall survival (OS). A total of 23,778 patients with stage III-IV colonic adenocarcinoma were treated with immunotherapy during the study period compared to 114,753 controls. Immunotherapy treated patients were younger (median age 61 vs. 67 y; P<0.001), more often male (57.3% vs. 50.7%, P<0.001), had more private insurance (44.1% vs. 33.7%; P<0.001), had more left-sided tumors (49.5% vs. 39.1%; P<0.001) and liver metastasis (80.2% vs. 61.7%; P<0.001) than controls. Immunotherapy patients received more standard chemotherapy (49.8% vs. 41.6%; P<0.001). After propensity-score matching, mean OS was significantly shorter in the immunotherapy group compared with controls (34.7 vs. 36.2 mo; P=0.008). Cox regression analysis demonstrated that immunotherapy was associated with increased risk for mortality (HR: 1.1; 95% CI: 1.02-1.18; P=0.005). Patients who received immunotherapy had lower 90-day mortality rates compared with controls (2.3% vs. 3.6%; P=0.004), but the groups had equivalent 30-day mortality rates (0.7% vs. 0.8%; P=0.76). Immunotherapy showed no improvement in OS in patients with stage III-IV colon cancer.

Effect of autologous dendritic cell cytokine-induced killer on refractory metastatic colorectal cancer: a matched case-control comparative study

Background

Patients with metastatic colorectal cancer (mCRC) who are refractory to two or more lines of systemic chemotherapy have limited therapeutic options. The aim of this study was to evaluate the effect of autologous dendritic cell cytokine-induced killer (DC-CIK) transfer on the survival of patients with mCRC who are refractory or intolerant to at least two lines of systemic chemotherapies.

Methods

A matched case-control comparative study was conducted with patients who received DC-CIK immunotherapy in addition to standard chemotherapy (cases) and those with standard chemotherapy alone (controls). The primary objective was to compare the duration of oncologic survival, including overall survival (OS) and progression-free survival (PFS), between the two groups.

Results

A total of 27 cases and 27 controls were included. The median OS in the DC-CIK case group was 18.73 ± 5.48 months, which was significantly longer than that in the control group (14.23 ± 1.90 months, p = 0.045). However, there was no significant difference in PFS between the two groups (p = 0.086). Subgroup analysis showed that in patients with liver or extra-regional lymph node metastasis, DC-CIK cases had longer OS than controls (17.0 vs. 11.87 months, p = 0.019; not match vs. 6.93 months, p = 0.002, respectively). In patients with Eastern Cooperative Oncology Group (ECOG) scale 0 or wild RAS/BRAF, DC-CIK cases showed a significant increase in OS duration compared to controls (28.03 vs. 14.53 months, p = 0.038; 18.73 vs. 11.87 months, p = 0.013, respectively).

Conclusions

The addition of autologous DC-CIK to standard chemotherapy had a positive effect on OS of patients with refractory mCRC, especially those with liver or extra-regional lymph node metastasis, ECOG = 0, and wild RAS/BRAF status.

Current Technologies and Future Perspectives in Immunotherapy towards a Clinical Oncology Approach

Immunotherapy is now established as a potent therapeutic paradigm engendering antitumor immune response against a wide range of malignancies and other diseases by modulating the immune system either through the stimulation or suppression of immune components such as CD4+ T cells, CD8+ T cells, B cells, monocytes, macrophages, dendritic cells, and natural killer cells. By targeting several immune checkpoint inhibitors or blockers (e.g., PD-1, PD-L1, PD-L2, CTLA-4, LAG3, and TIM-3) expressed on the surface of immune cells, several monoclonal antibodies and polyclonal antibodies have been developed and already translated clinically. In addition, natural killer cell-based, dendritic cell-based, and CAR T cell therapies have been also shown to be promising and effective immunotherapeutic approaches. In particular, CAR T cell therapy has benefited from advancements in CRISPR-Cas9 genome editing technology, allowing the generation of several modified CAR T cells with enhanced antitumor immunity. However, the emerging SARS-CoV-2 infection could hijack a patient's immune system by releasing pro-inflammatory interleukins and cytokines such as IL-1β, IL-2, IL-6, and IL-10, and IFN-γ and TNF-α, respectively, which can further promote neutrophil extravasation and the vasodilation of blood vessels. Despite the significant development of advanced immunotherapeutic technologies, after a certain period of treatment, cancer relapses due to the development of resistance to immunotherapy. Resistance may be primary (where tumor cells do not respond to the treatment), or secondary or acquired immune resistance (where tumor cells develop resistance gradually to ICIs therapy). In this context, this review aims to address the existing immunotherapeutic technologies against cancer and the resistance mechanisms against immunotherapeutic drugs, and explain the impact of COVID-19 on cancer treatment. In addition, we will discuss what will be the future implementation of these strategies against cancer drug resistance. Finally, we will emphasize the practical steps to lay the groundwork for enlightened policy for intervention and resource allocation to care for cancer patients.

Targeted therapy and immunotherapy for orbital and periorbital tumors: a major review

Traditionally, for patients who are poor candidates for surgery and/or radiotherapy, palliative chemotherapy is often offered but with significant toxic side effects. However, recent advancements in our understanding of tumor biology and molecular genetics have brought new understanding to the molecular pathways of certain tumors and cancers. This has ushered in a new era of precision medicine specific to a tumor or cancer treatment pathway (targeted therapy) or directed to host-tumor responses (immunotherapy). This article will focus on recent updates in the application of available targeted and immunotherapy for managing orbital and periorbital tumors and tumor-like conditions, which include cutaneous basal cell carcinoma, cutaneous squamous cell carcinoma, cutaneous melanoma, Merkel cell carcinoma, sebaceous gland carcinoma, solitary fibrous tumor, dermatofibrosarcoma protuberans, orbital meningioma, neurofibromatosis, Langerhans cell histiocytosis, ocular adnexal lymphoma, orbital lymphatic malformation, and adenoid cystic carcinoma.

Fundamental concepts of protein therapeutics and spacing in oncology: an updated comprehensive review

Current treatment regimens in cancer cases cause significant side effects and cannot effectively eradicate the advanced disease. Hence, much effort has been expended over the past years to understand how cancer grows and responds to therapies. Meanwhile, proteins as a type of biopolymers have been under commercial development for over three decades and have been proven to improve the healthcare system as effective medicines for treating many types of progressive disease, such as cancer. Following approving the first recombinant protein therapeutics by FDA (Humulin), there have been a revolution for drawing attention toward protein-based therapeutics (PTs). Since then, the ability to tailor proteins with ideal pharmacokinetics has provided the pharmaceutical industry with an important noble path to discuss the clinical potential of proteins in oncology research. Unlike traditional chemotherapy molecules, PTs actively target cancerous cells by binding to their surface receptors and the other biomarkers particularly associated with tumorous or healthy tissue. This review analyzes the potential and limitations of protein therapeutics (PTs) in the treatment of cancer as well as highlighting the evolving strategies by addressing all possible factors, including pharmacology profile and targeted therapy approaches. This review provides a comprehensive overview of the current state of PTs in oncology, including their pharmacology profile, targeted therapy approaches, and prospects. The reviewed data show that several current and future challenges remain to make PTs a promising and effective anticancer drug, such as safety, immunogenicity, protein stability/degradation, and protein-adjuvant interactions.

New Approaches in Early-Stage NSCL Management: Potential Use of PARP Inhibitors and Immunotherapy Combination

Lung cancer is the second most common cancer in the world, being the first cause of cancer-related mortality. Surgery remains the only potentially curative treatment for Non-Small Cell Lung Cancer (NSCLC), but the recurrence risk remains high (30-55%) and Overall Survival (OS) is still lower than desirable (63% at 5 years), even with adjuvant treatment. Neoadjuvant treatment can be helpful and new therapies and pharmacologic associations are being studied. Immune Checkpoint Inhibitors (ICI) and PARP inhibitors (PARPi) are two pharmacological classes already in use to treat several cancers. Some pre-clinical studies have shown that its association can be synergic and this is being studied in different settings. Here, we review the PARPi and ICI strategies in cancer management and the information will be used to develop a clinical trial to evaluate the potential of PARPi association with ICI in early-stage neoadjuvant setting NSCLC.

Osmani R, Hani U, Yoonus Thajudeen K, Kiran Raj G, Gowda DV. Recent advances in the liposomal nanovesicles based immunotherapy in the treatment of cancer: A review

Immunotherapy, along with chemotherapy, targeted delivery, radiation and surgery has become one of the most common cancer treatments. The aim of cancer immunology is to use the bodys immune system to combat tumors and develop a robust antitumor immune response. In the last few years, immune checkpoint inhibitors and chimeric antigen receptor-modified T cells have made substantial advancements in cancer immunotherapy. By boosting cell type-specific delivery and immunological responses, nanocarriers like liposomes have the ability to enhance greater immune responses. The efficacy of anti-tumor therapeutics is being significantly improved as liposomes can assist in resolving a number of issues that can arise from a variety of cancer immunotherapies. Since, liposomes can be loaded with both hydrophilic and hydrophobic drugs and protect the immunotherapeutic agents loaded inside the core, they offer significant advantages over other nano delivery systems. The use of liposomes for accurate and timely delivery of immunotherapies to particular targeted neoplasms, with little or no injury to healthy cells, maximizes immunotherapy efficacy. Liposomes are also suitable vehicles for delivering medications simultaneously with other therapies such as chemotherapy, radiation, and phototherapy. Liposomal nanoparticles will be introduced and used as an objective immunotherapy delivery system for great precision, making them a viable cancer treatment approach.With an emphasis on dendritic cells, T cells, tumor and natural killer cells, and macrophages; outline of many forms of immune-therapies in oncology and cutting-edge advances in liposomal nanovesicles for cancer immunotherapy are covered in this review.

Estrogen Receptor Signaling in the Immune System

The immune system functions in a sexually dimorphic manner, with females exhibiting more robust immune responses than males. However, how female sex hormones affect immune function in normal homeostasis and in autoimmunity is poorly understood. In this review, we discuss how estrogens affect innate and adaptive immune cell activity and how dysregulation of estrogen signaling underlies the pathobiology of some autoimmune diseases and cancers. The potential roles of the major circulating estrogens, and each of the 3 estrogen receptors (ERα, ERβ, and G-protein coupled receptor) in the regulation of the activity of different immune cells are considered. This provides the framework for a discussion of the impact of ER modulators (aromatase inhibitors, selective estrogen receptor modulators, and selective estrogen receptor downregulators) on immunity. Synthesis of this information is timely given the considerable interest of late in defining the mechanistic basis of sex-biased responses/outcomes in patients with different cancers treated with immune checkpoint blockade. It will also be instructive with respect to the further development of ER modulators that modulate immunity in a therapeutically useful manner.

Where Do We Stand with Immunotherapy for Advanced Pancreatic Ductal Adenocarcinoma: A Synopsis of Clinical Outcomes

Pancreatic cancer is the seventh leading cause of cancer-related mortality in both sexes across the globe. It is associated with extremely poor prognosis and remains a critical burden worldwide due to its low survival rates. Histologically, pancreatic ductal adenocarcinoma (PDAC) accounts for 80% of all pancreatic cancers; the majority of which are diagnosed at advanced stages, which makes them ineligible for curative surgery. Conventional chemotherapy provides a five-year overall survival rate of less than 8% forcing scientists and clinicians to search for better treatment strategies. Recent discoveries in cancer immunology have resulted in the incorporation of immunotherapeutic strategies for cancer treatment. Particularly, immune-checkpoint inhibitors, adoptive cell therapies and cancer vaccines have already shifted guidelines for some malignancies, although their efficacy in PDAC has yet to be elucidated. In this review, we summarize the existing clinical data on immunotherapy clinical outcomes in patients with advanced or metastatic PDAC.

Mathematical modeling of cancer immunotherapy for personalized clinical translation

Encouraging advances are being made in cancer immunotherapy modeling, especially in the key areas of developing personalized treatment strategies based on individual patient parameters, predicting treatment outcomes and optimizing immunotherapy synergy when used in combination with other treatment approaches. Here we present a focused review of the most recent mathematical modeling work on cancer immunotherapy with a focus on clinical translatability. It can be seen that this field is transitioning from pure basic science to applications that can make impactful differences in patients' lives. We discuss how researchers are integrating experimental and clinical data to fully inform models so that they can be applied for clinical predictions, and present the challenges that remain to be overcome if widespread clinical adaptation is to be realized. Lastly, we discuss the most promising future applications and areas that are expected to be the focus of extensive upcoming modeling studies.

The immunoregulation effect of tumor microenvironment in pancreatic ductal adenocarcinoma

Pancreatic cancer has the seventh highest death rate of all cancers. The absence of any serious symptoms, coupled with a lack of early prognostic and diagnostic markers, makes the disease untreatable in most cases. This leads to a delay in diagnosis and the disease progresses so there is no cure. Only about 20% of cases are diagnosed early. Surgical removal is the preferred treatment for cancer, but chemotherapy is standard for advanced cancer, although patients can eventually develop drug resistance and serious side effects. Chemoresistance is multifactorial because of the interaction among pancreatic cancer cells, cancer stem cells, and the tumor microenvironment (TME). Nevertheless, more pancreatic cancer patients will benefit from precision treatment and targeted drugs. This review focuses on the immune-related components of TME and the interactions between tumor cells and TME during the development and progression of pancreatic cancer, including immunosuppression, tumor dormancy and escape. Finally, we discussed a variety of immune components-oriented immunotargeting drugs in TME from a clinical perspective.

An Extensive Review on Preclinical and Clinical Trials of Oncolytic Viruses Therapy for Pancreatic Cancer

Chemotherapy resistance and peculiar tumor microenvironment, which diminish or mitigate the effects of therapies, make pancreatic cancer one of the deadliest malignancies to manage and treat. Advanced immunotherapies are under consideration intending to ameliorate the overall patient survival rate in pancreatic cancer. Oncolytic viruses therapy is a new type of immunotherapy in which a virus after infecting and lysis the cancer cell induces/activates patients’ immune response by releasing tumor antigen in the blood. The current review covers the pathways and molecular ablation that take place in pancreatic cancer cells. It also unfolds the extensive preclinical and clinical trial studies of oncolytic viruses performed and/or undergoing to design an efficacious therapy against pancreatic cancer.

Genetic Characteristics of Resectable Colorectal Cancer with Pulmonary Metastasis

The lung is the most common extra-abdominal metastasis site of colorectal cancer (CRC). This study aimed to investigate the genetic variation of pulmonary metastases (PM) and primary tumors in resectable CRC. The clinical data of 410 patients with PM after CRC surgery and 33 paraffin-embedded tissue samples from January 2012 to July 2019 in our hospital were collected retrospectively. Next, 450-panel gene detection technologies based on next-generation sequencing (NGS) were used to analyze the changes in the gene map and the overall variation in cancer-related genes in PM and primary tumors. After quality control, 19 samples were included in the final gene analysis. The results showed that APC (89.5%), TP53 (89.5%), and KRAS (53%) were the most common mutations in PM and primary tumors, but the gene amplification variation was enriched in primary tumors (4.6% vs. 11.4%). KRAS G12D was the most common site variation of the KRAS gene in both PM and primary tumors of CRC. There was no hotspot mutation in the TP53 locus in CRC, and the TP53 mutation in the PM was consistent with that in the primary lesion. The microsatellite instability (MSI) levels of 10 patients were MSS. The mean tumor mutation burden (TMB) of the primary tumor (5.3 muts·Mb^-1) was slightly higher than that of metastasis (5.0 muts·Mb^-1). In our institution, the genetic characteristics of resectable PM from CRC may be highly consistent with those of the primary tumor.

Immunotherapy in Combination with Well-Established Treatment Strategies in Pancreatic Cancer: Current Insights

Pancreatic ductal adenocarcinoma (PDAC) is the most common type of pancreatic cancer and fourth most common cause of death in developed countries. Despite improved survival rates after resection combined with adjuvant chemotherapy or neoadjuvant chemotherapy, recurrence still occurs in a high percentage of patients within the first 2 years after resection. Immunotherapy aims to improve antitumor immune responses and reduce toxicity providing a more specific, targeted therapy compared to chemotherapy and has been proved an efficient therapeutic tool for many solid tumors. In this work, we present the latest advances in PDAC treatment using a combination of immunotherapy with other interventions such as chemotherapy and/or radiation both at neoadjuvant and adjuvant setting. Moreover, we outline the role of the tumor microenvironment as a key barrier to immunotherapy efficacy and examine how immunotherapy biomarkers may be used to detect immunotherapy’s response.

Opportunities and challenges in targeted therapy and immunotherapy for pancreatic cancer

Pancreatic cancer is one of the most malignant tumours with a poor prognosis. In recent years, the incidence of pancreatic cancer is on the rise. Traditional chemotherapy and radiotherapy for pancreatic cancer have been improved, first-line and second-line palliative treatments have been developed, and adjuvant treatments have also been used in clinical. However, the 5-year survival rate is still less than 10% and new treatment methods such as targeted therapy and immunotherapy need to be investigated. In the past decades, many clinical trials of targeted therapies and immunotherapies for pancreatic cancer were launched and some of them showed an ideal prospect in a subgroup of pancreatic cancer patients. The experience of both success and failure of these clinical trials will be helpful to improve these therapies in the future. Therefore, the current research progress and challenges of selected targeted therapies and immunotherapies for pancreatic cancer are reviewed.

Harnessing the immune system against cancer: current immunotherapy approaches and therapeutic targets

Cancer immunotherapy is a rapidly evolving concept that has been given the tag "fifth pillar" of cancer therapy while radiation therapy, chemotherapy, surgery and targeted therapy remain the other four pillars. This involves the stimulation of the immune system to control tumor growth and it specifically targets the neoplastic cells rather than the normal cells. Conventional chemotherapy has many limitations which include drug resistance, recurrence of cancer and severe adverse effects. Immunology has made major treatment breakthroughs for several cancers such as colorectal cancer, prostate cancer, breast cancer, lung cancer, liver cancer, kidney cancer, stomach cancer, acute lymphoblastic leukaemia etc. Currently, therapeutic strategies harnessing the immune system involve Checkpoint inhibitors, Chimeric antigen receptor T cells (CAR T cells), Monoclonal antibodies, Cancer vaccines, Cytokines, Radio-immunotherapy and Oncolytic virus therapy. The molecular characterization of several tumor antigens (TA) indicates that these TA can be utilized as promising candidates in cancer immunotherapy strategies. Here in this review, we highlight and summarize the different categories of emerging cancer immunotherapies along with the immunologically recognized tumor antigens involved in the tumor microenvironment.

Vaccines as Priming Tools for T Cell Therapy for Epithelial Cancers

Simple Summary

Despite all of the impressive progress that has been made in the field of cancer therapy, cancer continues to devastate the lives of many. Recent efforts have focused on taking advantage of the patients’ immune system, modifying and employing it to attack cancer cells more efficiently. Therapeutic cancer vaccines are part of the armamentarium used for that purpose. In this review, we discuss the role of the immune system in the fight against cancer, the various strategies that are aimed at engaging the immune system, and how therapeutic cancer vaccines can be used as a self-standing strategy or as a means to leverage other immunotherapies to deliver more efficient results. We elaborate on the obstacles that are present, why immune therapies do not work equally well on all patients, and how vaccines can potentially play a role in improving cancer outcomes.

Abstract

Impressive progress has recently been made in the field of cancer immunotherapy with the adoptive transfer of T cells, a successful personalized strategy, and checkpoint inhibitors (CPI) having extended the survival of numerous patients. However, not all patients have been able to benefit from these innovations. A key determinant of the responsiveness to cancer immunotherapies is the presence of T cells within the tumors. These tumor-infiltrating lymphocytes (TILs) are crucial in controlling tumor growth and their activity is being potentiated by immunotherapies. Although some epithelial cancers are associated with spontaneous T-cell and B-cell responses, which makes them good candidates for immunotherapies, it remains to create strategies that would promote lymphocyte infiltration and enable sustained immune responses in immune-resistant tumors. Therapeutic cancer vaccines hold the potential of being able to render “cold”, poorly infiltrated tumors into “hot” tumors that would be receptive to cellular immunotherapies. In this review, we elaborate on the obstacles that need to be overcome and the strategies that are being explored to that end, including various types of antigen repertoires and different vaccine platforms and combinations with other available treatments.

Immunotherapy for gastric cancer: a 2021 update

Gastric cancer, the fifth most frequent cancer and the fourth leading cause of cancer deaths, accounts for a devastating death rate worldwide. Since the majority of patients with gastric cancer are diagnosed at advanced stages, they are not suitable for surgery and present with locally advanced or metastatic disease. Recent advances in immunotherapy have elicited a considerable amount of attention as viable therapeutic options for several cancer types. This work presents a summary of the currently ongoing clinical trials and critically addresses the efficacy of a large spectrum of immunotherapy approaches in the general population for gastric cancer as well as in relation to tumor genetic profiling.

Hedgehog Pathway Inhibitors against Tumor Microenvironment

Targeting the hedgehog (HH) pathway to treat aggressive cancers of the brain, breast, pancreas, and prostate has been ongoing for decades. Gli gene amplifications have been long discovered within malignant glioma patients, and since then, inhibitors against HH pathway-associated molecules have successfully reached the clinical stage where several of them have been approved by the FDA. Albeit this success rate implies suitable progress, clinically used HH pathway inhibitors fail to treat patients with metastatic or recurrent disease. This is mainly due to heterogeneous tumor cells that have acquired resistance to the inhibitors along with the obstacle of effectively targeting the tumor microenvironment (TME). Severe side effects such as hyponatremia, diarrhea, fatigue, amenorrhea, nausea, hair loss, abnormal taste, and weight loss have also been reported. Furthermore, HH signaling is known to be involved in the regulation of immune cell maturation, angiogenesis, inflammation, and polarization of macrophages and myeloid-derived suppressor cells. It is critical to determine key mechanisms that can be targeted at different levels of tumor development and progression to address various clinical issues. Hence current research focus encompasses understanding how HH controls TME to develop TME altering and combinatorial targeting strategies. In this review, we aim to discuss the pros and cons of targeting HH signaling molecules, understand the mechanism involved in treatment resistance, reveal the role of the HH pathway in anti-tumor immune response, and explore the development of potential combination treatment of immune checkpoint inhibitors with HH pathway inhibitors to target HH-driven cancers.

A topography of immunotherapies against gastrointestinal malignancies

Gastrointestinal (GI) cancers are one of the leading causes of death worldwide. Although various approaches are implemented to improve the health condition of GI patients, none of the treatment protocols promise for eradicating cancer. However, a treatment mechanism against any kind of disease condition is already existing executing inside the human body. The 'immune system' is highly efficient to detect and destroy the unfavourable events of the body including tumor cells. The immune system can restrict the growth and proliferation of cancer. Cancer cells behave much smarter and adopt new mechanisms for hiding from the immune cells. Thus, cancer immunotherapy might play a decisive role to train the immune system against cancer. In this review, we have discussed the immunotherapy permitted for the treatment of GI cancers. We have discussed various methods and mechanisms, periodic development of cancer immunotherapies, approved biologicals, completed and ongoing clinical trials, role of various biopharmaceuticals, and epigenetic factors involved in GI cancer immunotherapies (graphical abstract Figure 1).

Resistance to immunotherapy in human malignancies: Mechanisms, research progresses, challenges, and opportunities

Despite remarkable advances in different types of cancer therapies, an effective therapeutic strategy is still a major and significant challenge. One of the most promising approaches in this regard is immunotherapy, which takes advantage of the patients' immune system; however, the many mechanisms that cancerous cells harbor to extend their survival make it impossible to gain perfect eradication of tumors. The response rate to cancer immunotherapies, especially checkpoint inhibitors and adoptive T cell therapy, substantially differs in various cancer types with the highest rates in advanced melanoma and non-small cell lung cancer. Indeed, the lack of response in many tumors indicates primary resistance that can originate from either tumor cells (intrinsic) or tumor microenvironment (extrinsic). On the other hand, some tumors show an initial response to immunotherapy followed by relapse in few months (acquired resistance). Understanding the underlying molecular mechanisms of immunotherapy resistance makes it possible to develop effective strategies to overcome this hurdle and boost therapy outcomes. In this review, we take a look at immunotherapy strategies and go through a number of primary and acquired resistance mechanisms. Also, we present various ongoing methods to overcoming resistance and introduce some promising fields to improve the outcome of immunotherapy in patients affected with cancer.

Immunotherapy for gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs): a 2021 update

Neuroendocrine neoplasms (NENs) are a group of heterogeneous malignancies, arising from the neuroendocrine system. These neoplasms are divided into two distinct groups, the low-proliferating, well-differentiated neuroendocrine tumors (NETs), and the highly-proliferating, poorly-differentiated neuroendocrine carcinomas (NECs). Recent data demonstrate that the incidence of gastroenteropancreatic (GEP) neuroendocrine neoplasms, GEP-NETs and GEP-NECs, has increased exponentially over the last three decades. Although surgical resection is considered the best treatment modality, patients with GEP-NETs often present with advanced disease at diagnosis associated with a 5-year survival rate of 57% for well-differentiated tumors, and only 5.2% for small-cell tumors. Immunotherapy is a novel treatment approach, which has demonstrated effective and promising therapeutic results against several types of cancers. In the present study, we review the current ongoing clinical trials and to evaluate the efficacy of immunotherapy in GEP-NENs. Furthermore, we analyze the importance of tumor genetic profiling and its clinical implications in immunotherapy response.

Paving the Way for Immunotherapy in Pediatric Acute Myeloid Leukemia: Current Knowledge and the Way Forward

Simple Summary

Immunotherapy may be an attractive treatment option to increase survival, and to reduce treatment-related side effects, for children with acute myeloid leukemia (AML). While immunotherapies have shown successes in many cancer types, the development and subsequent clinical implementation have proven difficult in pediatric AML. To expedite the development of immunotherapy, it will be crucial to understand which pediatric AML patients are likely to respond to immunotherapies. Emerging research in solid malignancies has shown that the number and phenotype of immune cells in the tumor microenvironment is predictive of response to several types of immunotherapies. Such a predictive model may also be applicable for AML and, thus, knowledge on the immune cells infiltrating the bone marrow environment is needed. Here, we discuss the current state of knowledge on these infiltrating immune cells in pediatric AML, as well as ongoing immunotherapy trials, and provide suggestions concerning the way forward.

Abstract

Immunotherapeutic agents may be an attractive option to further improve outcomes and to reduce treatment-related toxicity for pediatric AML. While improvements in outcome have been observed with immunotherapy in many cancer types, immunotherapy development and implementation into patient care for both adult and pediatric AML has been hampered by an incomplete understanding of the bone marrow environment and a paucity of tumor-specific antigens. Since only a minority of patients respond in most immunotherapy trials across different cancer types, it will be crucial to understand which children with AML are likely to respond to or may benefit from immunotherapies. Immune cell profiling efforts hold promise to answer this question, as illustrated by the development of predictive scores in solid cancers. Such information on the number and phenotype of immune cells during current treatment regimens will be pivotal to generate hypotheses on how and when to intervene with immunotherapy in pediatric AML. In this review, we discuss the current understanding of the number and phenotype of immune cells in the bone marrow in pediatric AML, ongoing immunotherapy trials and how comprehensive immune profiling efforts may pave the way for successful clinical trials (and, ultimately, implementation into patient care).

Can Immune Suppression and Epigenome Regulation in Placenta Offer Novel Insights into Cancer Immune Evasion and Immunotherapy Resistance?

Cancer is the second leading cause of mortality and morbidity in the developed world. Cancer progression involves genetic and epigenetic alterations, accompanied by aggressive changes, such as increased immune evasion, onset of metastasis, and drug resistance. Similar to cancer, DNA hypomethylation, immune suppression, and invasive cell behaviours are also observed in the human placenta. Mechanisms that lead to the acquisition of invasive behaviour, immune evasion, and drug and immunotherapy resistance are presently under intense investigations to improve patient outcomes. Here, we review current knowledge regarding the similarities between immune suppression and epigenome regulation, including the expression of repetitive elements (REs), endogenous retroviruses (ERVs) and transposable elements (TEs) in cells of the placenta and in cancer, which are associated with changes in immune regulation and invasiveness. We explore whether immune suppression and epigenome regulation in placenta offers novel insights into immunotherapy resistance in cancer, and we also discuss the implications and the knowledge gaps relevant to these findings, which are rapidly being accrued in these quite disparate research fields. Finally, we discuss potential linkages between TE, ERV and RE activation and expression, regarding mechanisms of immune regulation in placenta and cancer. A greater understanding of the role of immune suppression and associated epigenome regulation in placenta could help to elucidate some comparable mechanisms operating in cancer, and identify potential new therapeutic targets for treating cancer.

The role of combining immunotherapy with primary (Chemo)radiotherapy in curative treatment settings of the head and neck cancer

The introduction of immunotherapy into the radical management of head and neck cancer (HNC) is a fast moving phenomenon, which is constantly developing. Although now established in the management of recurrent and metastatic disease in HNC, its use in radical treatment is being investigated in a whole spectrum of clinical trials looking at which immune altering agents give the best results, which can be added safely to radiotherapy, chemotherapy, and chemoradiotherapy for greatest efficiency and when the most appropriate time to add these agents is in the neoadjuvant, concurrent on adjuvant settings. These multiple questions produce a complex matrix for HNC investigators and this article brings together the existing evidence and contemporary trials going on with immunotherapy in HNC, giving an up to date snapshot of present investigations and near future directions for further research.

Challenges and perspectives for immunotherapy in oesophageal cancer: A look to the future (Review)

Oesophageal cancer is one of the most aggressive malignancies with limited treatment options, thus resulting in a high morbidity and mortality. With 5‑year survival rates of only 5‑10%, oesophageal cancer holds a dismal prognosis for patients. In order to improve overall survival, the early diagnosis and tools for patient stratification for personalized treatment are urgent needs. A minority of oesophageal cancers belong to the spectrum of Lynch syndrome‑associated cancers and are characterized by microsatellite instability (MSI). Microsatellite instability is a consequence of defective mismatch repair protein functions and it has been well characterized in other gastrointestinal tumours, such as colorectal and gastric cancer. In the latter, high levels of MSI are associated with a better prognosis and with an increased benefit to immune‑based therapies. Therefore, similar therapeutic approaches could offer an opportunity of treatment for oesophageal cancer patients with MSI. Apart from immune checkpoint inhibitors, other immunotherapies such as adoptive T‑cell transfer, peptide vaccine and oncolytic viruses are under investigation in oesophageal cancer patients. In the present review, the rationale and current knowledge about immunotherapies in oesophageal cancer are summarised.

Critical review of oncology clinical trial design under non-proportional hazards

In trials of novel immuno-oncology drugs, the proportional hazards (PH) assumption often does not hold for the primary time-to-event (TTE) efficacy endpoint, likely due to the unique mechanism of action of these drugs. In practice, when it is anticipated that PH may not hold for the TTE endpoint with respect to treatment, the sample size is often still calculated under the PH assumption, and the hazard ratio (HR) from the Cox model is still reported as the primary measure of the treatment effect. Sensitivity analyses of the TTE data using methods that are suitable under non-proportional hazards (non-PH) are commonly pre-planned. In cases where a substantial deviation from the PH assumption is likely, we suggest designing the trial, calculating the sample size and analyzing the data, using a suitable method that accounts for non-PH, after gaining alignment with regulatory authorities. In this comprehensive review article, we describe methods to design a randomized oncology trial, calculate the sample size, analyze the trial data and obtain summary measures of the treatment effect in the presence of non-PH. For each method, we provide examples of its use from the recent oncology trials literature. We also summarize in the Appendix some methods to conduct sensitivity analyses for overall survival (OS) when patients in a randomized trial switch or cross-over to the other treatment arm after disease progression on the initial treatment arm, and obtain an adjusted or weighted HR for OS in the presence of cross-over. This is an example of the treatment itself changing at a specific point in time - this cross-over may lead to a non-PH pattern of diminishing treatment effect.

Primary Human Dendritic Cells and Whole-Blood Based Assays to Evaluate Immuno-Modulatory Properties of Heat-Killed Commensal Bacteria

There is mounting evidence that the microbiome plays a critical role in training and maturation of the host immune system. Pre-clinical and clinical studies have shown that microbiome perturbation is correlated with sub-optimal host responses to vaccines and cancer immunotherapy. As such, identifying species of commensal bacteria capable of modulating immunological outcomes is of considerable interest. Currently, the lack of reliable primary immune cell-based assays capable of differentiating immuno-modulatory properties of various commensal bacteria is a major limitation. Here, we demonstrate that primary human monocyte-derived dendritic cells (MoDC) are capable of stratifying different strains of live and heat-killed commensal bacteria in an in vitro culture system. Specifically, heat-killed bacterial strains were able to differentially modulate co-stimulation/maturation markers CD80, CD83, and HLA-DR, as well as cytokine/chemokine signatures, such as IL-1b, MIP-1a, and TNFa in primary human MoDC. We further validated our observations using the TruCulture^® (Myriad RBM, Inc., Austin, TX, USA) whole-blood ex vivo culture system. Using this ex vivo system allowed us to measure immune-altering effects of commensal bacteria in primary human whole-blood. As such, we report that both these primary in vitro and ex vivo systems are robust and enable identification, stratification, and differentiation of various commensal bacteria as potential modulators of host immunity.

The Proposition of the Pulmonary Route as an Attractive Drug Delivery Approach of Nano-Based Immune Therapies and Cancer Vaccines to Treat Lung Tumors

Lung cancer is the leading cause of cancer related deaths globally, making it a major health concern. The lung’s permissive rich microenvironment is ideal for supporting outgrowth of disseminated tumors from pre-existing extra-pulmonary malignancies usually resulting in high mortality. Tumors occurring in the lungs are difficult to treat, necessitating the need for the development of advanced treatment modalities against primary tumors and secondary lung metastasis. In this review, we explore the pulmonary route as an attractive drug delivery approach to treat lung tumors. We also discuss the potential of pulmonary delivery of cancer vaccine vectors to induce mucosal immunity capable of preventing the seeding of tumors in the lung.

Current treatments for BCG failure in non-muscle invasive bladder cancer (NMIBC)

The treatment of choice for high-risk non-muscle invasive bladder cancer (NMIBC) is bacillus Calmette-Guérin (BCG). However, when this fails, the indicated treatment is radical cystectomy. In recent years, trials are being developed with various drugs to avoid this surgery in patients with BCG failure. The aim of this article is to update the treatments under study for bladder preservation in this patient population. Non-systematic review, searching PubMed with the terms "Bladder cancer", "Non-muscle invasive bladder cancer", "NMIBC", "BCG", "BCG-refractory", "Mitomycin C", "MMC", "Hyperthermia", "Electromotive Drug Administration", "EMDA". We used the search engines clinicaltrials.gov and clinicaltrialsregister.eu to find clinical trials. The only intravesical drug approved by the Food and Drug Administration (FDA) for carcinoma in situ (CIS) after failure to BCG is Valrubicin. Recently, the FDA has approved intravenous Pembrolizumab, following the publication of preliminary data from the KEYNOTE-057 study. Atezolizumab has demonstrated similar preliminary efficacy results. Only microwave-induced chemohyperthermia and EMDA-MMC (Electromotive Drug Administration) are recognized as alternatives in European guidelines. Other options under investigation are taxanes and gemcitabine, alone or in combination, recombinant viruses and device-assisted intravesical chemohyperthermia. The results of new drugs are promising, with a large number of trials underway. Knowing the mechanisms of resistance to BCG is essential to explore new therapeutic options.

Exploring the significance of novel immune-related gene signatures in the prognosis and immune features of pancreatic adenocarcinoma

BACKGROUND

Immune-related genes (IRGs) are associated with the prognosis of different cancers and are helpful for the diagnosis and management of systematic treatment for cancer patients. However, there have been a few corresponding studies in pancreatic adenocarcinoma (PAAD).

METHODS

The data of PAAD patients were obtained from the TCGA, GEO, and ICGC databases. Additionally, the expression profiles of the normal pancreas from the GTEx database were used to screen differentially expressed immune-related genes (DEIRGs). Cox regression analyses were used to explore overall survival (OS)- and progression-free survival (PFS)-related DEIRGs and to establish two nomograms for PAAD prognosis. Finally, transcription factor (TF), immune infiltration, and unsupervised consensus analyses were performed to understand the potential mechanisms.

RESULTS

An OS-prognostic signature based on seven DEIRGs and a PFS-prognostic signature based on seven DEIRGs were generated, and their robust prognostic ability was confirmed by ROC curves (OS: 0.736 ~ 0.774, PFS: 0.732 ~ 0.840). According to the risk score, the OS and PFS of the high-risk group were poorer than those of the low-risk group in the training set and four external validation sets. In addition, two nomograms based on the signatures and clinical variables also showed excellent discrimination. And two hub regulatory pathways were successfully validated in several independent datasets. Discernable patterns of DEIRGs in unsupervised consensus analysis showed that patients with low expression of immune checkpoints had a favorable prognosis.

CONCLUSION

Two DEIRG-based signatures can be used as independent tools for the prognostic prediction of PAAD and to provide potential novel immunotherapy targets.

A mathematical model for the quantification of a patient's sensitivity to checkpoint inhibitors and long-term tumour burden

A large proportion of patients with cancer are unresponsive to treatment with immune checkpoint blockade and other immunotherapies. Here, we report a mathematical model of the time-course of tumour responses to immune-checkpoint inhibitors. The model takes into account intrinsic tumour-growth rates, the rates of immune activation and of tumour–immune-cell interactions, and the efficacy of immune-mediated tumour killing. For 124 patients, four cancer types and two immunotherapy agents, the model reliably described the immune responses and final tumour burden across all different cancers and drug combinations examined. In validation cohorts from four clinical trials of checkpoint inhibitors (with a total of 177 patients), the model accurately stratified the patients according to reduced or increased long-term tumour burden. We also provide model-derived quantitative measures of treatment sensitivity for specific drug–cancer combinations. The model can be used to predict responses to therapy and to quantify specific drug–cancer sensitivities in individual patients.

PD-L1 Targeting Immune-Microbubble Complex Enhances Therapeutic Index in Murine Colon Cancer Models

Cancer immunotherapy has revolutionized the way different neoplasms are treated. Among the different variations of cancer immunotherapy, the checkpoint inhibitors targeting the programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) axis have been validated and are currently used in the clinics. Nevertheless, these therapeutic antibodies are associated with significant side effects and are known to induce immune-related toxicities. To address these issues, we have developed an immune-microbubble complex (IMC) which not only reduces the toxicities associated with the antibodies but also enhances the therapeutic efficacy when combined with focused ultrasound. The concept of IMCs could be applied to any type of antibody-based treatment regimens to maximize their therapeutic potential.

Immunotherapy Advances for Epithelial Ovarian Cancer

Simple Summary

The overall five-year survival rate in epithelial ovarian cancer is 44% and has only marginally improved in the past two decades. Despite an initial response to standard treatment consisting of chemotherapy and surgical removal of tumor, the lesions invariably recur, and patients ultimately die of chemotherapy resistant disease. New treatment modalities are needed in order to improve the prognosis of women diagnosed with ovarian cancer. One such modality is immunotherapy, which aims to boost the capacity of the patient’s immune system to recognize and attack the tumor cells. We performed a retrospective study to identify some of the most promising immune therapies for epithelial ovarian cancer. Special emphasis was given to immuno-oncology clinical trials.

Abstract

New treatment modalities are needed in order to improve the prognosis of women diagnosed with epithelial ovarian cancer (EOC), the most aggressive gynecologic cancer type. Most ovarian tumors are infiltrated by immune effector cells, providing the rationale for targeted approaches that boost the existing or trigger new anti-tumor immune mechanisms. The field of immuno-oncology has experienced remarkable progress in recent years, although the results seen with single agent immunotherapies in several categories of solid tumors have yet to extend to ovarian cancer. The challenge remains to determine what treatment combinations are most suitable for this disease and which patients are likely to benefit and to identify how immunotherapy should be incorporated into EOC standard of care. We review here some of the most promising immune therapies for EOC and focus on those currently tested in clinical trials.

Evaluation of an autologous cancer vaccine for the treatment of metastatic canine hemangiosarcoma: a preliminary study

Background

Canine hemangiosarcoma (HSA) is an aggressive cancer arising from multipotential bone marrow-derived stem cells. Anthracycline chemotherapy drugs have been the mainstay adjuvant chemotherapy following surgery with only modest improvement in survival and an attendant risk for adverse events. Immunotherapy, using a whole cell autologous cancer vaccine adjuvanted with MIM-SIS, may improve outcomes for dogs with HSA with a lower risk for adverse events compared with chemotherapy.

Results

In cultured DH82 canine monocyte-like cells, autologous cancer vaccines prepared from 13 dogs with HSA increased MHC-II surface expression ranging from 20.0-60.4% on single-stained cells, CD80 surface expression ranging from 23.7–45.9% on single-stained cells, and MHC-II/CD80 surface expression ranging from 7.2–20.1% on double-stained cells. Autologous cancer vaccines were able to, on average, stimulate an up-regulation of MHC-II and CD80 by 48-fold as compared to media only (MHC-II + CD80 + cells: 12.19 ± 3.70% vs. 0.25 ± 0.06%; p < 0.001). The overall median survival time for dogs treated with the autologous cancer vaccine was 142 days (range, 61 to 373 days). Dogs treated with the autologous cancer vaccine or maximum tolerated dose (MTD) chemotherapy had significantly (P < 0.001) longer survival than dogs treated with surgery alone. The 1-year survival rate was 12.5% for dogs treated with the autologous cancer vaccine, and 0% for dogs treated with surgery alone or MTD chemotherapy. No adverse events were observed in the dogs treated with the autologous cancer vaccine.

Conclusions

The adjuvanted autologous cancer vaccine is capable of up-regulating MHC-II and CD80 in cultured canine monocyte-derived cells, which are important stimulatory molecules in generating an immune response and improves survival time in dogs with metastatic (stage III) HSA when compared to surgical treatment alone. Autologous cancer vaccine-treated dogs had survival similar to those dogs treated with MTD chemotherapy without any observed adverse events. This autologous cancer vaccine represents an effective form of individualized immunotherapy that is an appealing option for dog owners not wanting to pursue adjuvant chemotherapy for HSA.

New immunotherapies for high-risk non-muscle invasive bladder cancer: Current state and future perspectives

BACKGROUND

The standard treatment for high-risk non-muscle invasive bladder tumors (NMIBT) is transurethral resection of the bladder and BCG instillations. However, responses are limited, and new therapeutic alternatives for these patients are required. The results of checkpoint inhibitors in advanced tumors have led to interest in the use of these molecules in NMIBT.

METHODS

We conducted a search on PubMed using the terms «bladder cancer» and «check point inhibitors». We have used the search engines clinicaltrials.gov and clinicaltrialsregister.eu for the search of clinical trials.

RESULTS

There are currently 5 trials in progress on BCG untreated patients. There are no results available. As for BCG non-responders, there are 15 ongoing trials, two of them with preliminary results: Keynote 057, with promising results with pembrolizumab, which has led the FDA to approve its use in January 2020, and SWOG S1605, which has shown similar results with atezolizumab. Other trials are using intravesical administration of these drugs, which is an attractive option if it is effective for cancer control.

CONCLUSIONS

Checkpoint inhibitors offer a new possibility for patients who do not respond to BCG. These will probably be used in the future for previously BCG untreated patients. Preliminary data from clinical trials show promising results. A good understanding of these molecules by urologists and the creation of multidisciplinary teams are crucial in order to offer the best therapeutic alternatives to these patients.

Immunotherapy for Hepatocellular Carcinoma: A 2021 Update

Hepatocellular carcinoma (HCC) is one of one of the most frequent liver cancers and the fourth leading cause of cancer-related mortality worldwide. Current treatment options such as surgery, neoadjuvant chemoradiotherapy, liver transplantation, and radiofrequency ablation will benefit only a very small percentage of patients. Immunotherapy is a novel treatment approach representing an effective and promising option against several types of cancer. The aim of our study is to present the currently ongoing clinical trials and to evaluate the efficacy of immunotherapy in HCC. In this paper, we demonstrate that combination of different immunotherapies or immunotherapy with other modalities results in better overall survival (OS) and progression-free survival (PFS) compared to single immunotherapy agent. Another objective of this paper is to demonstrate and highlight the importance of tumor microenvironment as a predictive and prognostic marker and its clinical implications in immunotherapy response.

Immunotherapy in Testicular Germ Cell Tumors

Testicular germ cell tumors (TGCTs) are malignancies with very high curative potential even in metastatic settings, mainly due to the introduction of cisplatin in the treatment of this disease. However, in a group of patients with cisplatin-refractory disease or with progressive disease despite high-dose salvage chemotherapy treatment, the prognosis is typically dismal. The triple combination of gemcitabine, oxaliplatin, and paclitaxel (GOP) has reasonable efficacy and is considered to be standard care for this group of patients. It remains to be seen, however, whether refractory TGCTs may represent a potential target for immune checkpoint inhibition. This review will focus on the rationale of the use of immunotherapy for platinum-refractory TGCTs and summarize data reporting experiences with immune checkpoint inhibitor treatment for this malignancy.

Polydopamine-Mesoporous Silica Core-Shell Nanoparticles for Combined Photothermal Immunotherapy

Cancer immunotherapy involves a cascade of events that ultimately leads to cytotoxic immune cells effectively identifying and destroying cancer cells. Responsive nanomaterials, which enable spatiotemporal orchestration of various immunological events for mounting a highly potent and long-lasting antitumor immune response, are an attractive platform to overcome challenges associated with existing cancer immunotherapies. Here, we report a multifunctional near-infrared (NIR)-responsive core-shell nanoparticle, which enables (i) photothermal ablation of cancer cells for generating tumor-associated antigen (TAA) and (ii) triggered release of an immunomodulatory drug (gardiquimod) for starting a series of immunological events. The core of these nanostructures is composed of a polydopamine nanoparticle, which serves as a photothermal agent, and the shell is made of mesoporous silica, which serves as a drug carrier. We employed a phase-change material as a gatekeeper to achieve concurrent release of both TAA and adjuvant, thus efficiently activating the antigen-presenting cells. Photothermal immunotherapy enabled by these nanostructures resulted in regression of primary tumor and significantly improved inhibition of secondary tumor in a mouse melanoma model. These biocompatible, biodegradable, and NIR-responsive core-shell nanostructures simultaneously deliver payload and cause photothermal ablation of the cancer cells. Our results demonstrate potential of responsive nanomaterials in generating highly synergistic photothermal immunotherapeutic response.

A Pilot Study of the Adverse Events Caused by the Combined Use of Bevacizumab and Vascular Endothelial Growth Factor Receptor-Targeted Vaccination for Patients with a Malignant Glioma

Anti-angiogenic therapy, targeting vascular endothelial growth factor (VEGF)-A/VEGF receptors (VEGFRs), is beneficial for tumor growth prevention in a malignant glioma. A simultaneous blockade using both bevacizumab (Bev), which targets circulating VEGF-A, and a multi-kinase inhibitor on VEGFRs was more effective for advanced solid cancers, including melanoma and renal cell carcinoma. However, previous clinical trials demonstrated a high adverse event rate. Additionally, no studies previously assessed treatment efficacy and safety using both VEGF-A and VEGFR-targeted agents for malignant gliomas. We had conducted clinical trials investigating VEGFRs peptide vaccination in patients with malignant gliomas, in which the treatment exhibited safety and yielded therapeutic effects in some patients. The combined use of Bev and VEGFRs vaccination may enhance the anti-tumor effect in malignant gliomas. In this pilot study, the adverse event profile in patients treated with Bev after the vaccination was investigated to establish this treatment strategy, in comparison to those treated with Bev collected from the published data or treated with the vaccination alone. In our previous clinical studies on patients with malignant gliomas, Bev was administered to 13 patients after VEGFRs vaccinations. One patient had a Grade 4 pulmonary embolism. Two patients had Grade 2 cerebral infarctions. There were no significant differences in the adverse event rates among patients treated with Bev, with the vaccination, or with Bev after the vaccination. Although careful observation is imperative for patients after this combination treatment strategy, VEGFRs-targeted vaccination may coexist with Bev for malignant gliomas.

Antitumour dendritic cell vaccination in a priming and boosting approach

Mobilizing antitumour immunity through vaccination potentially constitutes a powerful anticancer strategy but has not yet provided robust clinical benefits in large patient populations. Although major hurdles still exist, we believe that currently available strategies for vaccines that target dendritic cells or use them to present antitumour antigens could be integrated into existing clinical practice using prime-boost approaches. In the priming phase, these approaches capitalize on either standard treatment modalities to trigger in situ vaccination and release tumour antigens or vaccination with dendritic cells loaded with tumour lysates or patient-specific neoantigens. In a second boost phase, personalized synthetic vaccines specifically boost T cells that were triggered during the priming phase. This immunotherapy approach has been enabled by the substantial recent improvements in dendritic cell vaccines. In this Perspective, we discuss these improvements, highlight how the prime-boost approach can be translated into clinical practice and provide solutions for various anticipated hurdles.

In situ Vaccine Plus Checkpoint Blockade Induces Memory Humoral Response

In a syngeneic murine melanoma (MEL) model, we recently reported an in situ vaccination response to combined radiation (RT) and intra-tumoral (IT) injection of anti-GD2 hu14. 18-IL2 immunocytokine (IC). This combined treatment resulted in 71% complete and durable regression of 5-week tumors, a tumor-specific memory T cell response, and augmented response to systemic anti-CTLA-4 antibody checkpoint blockade. While the ability of radiation to diversify anti-tumor T cell response has been reported, we hypothesize that mice rendered disease-free (DF) by a RT-based ISV might also exhibit a heightened B cell response. C57BL/6 mice were engrafted with 2 × 10⁶ GD2+ B78 MEL and treated at a target tumor size of ~200 mm³ with 12 Gy RT, IT-IC on day (D)6-D10, and anti-CTLA-4 on D3, 6, and 9. Serum was collected via facial vein before tumor injection, before treatment, during treatment, after becoming DF, and following rejection of subcutaneous 2 × 10⁶ B78 MEL re-challenge on D90. Flow cytometry demonstrated the presence of tumor-specific IgG in sera from mice rendered DF and rejecting re-challenge with B78 MEL at D90 after starting treatment. Consistent with an adaptive endogenous anti-tumor humoral memory response, these anti-tumor antibodies bound to B78 cells and parental B16 cells (GD2-), but not to the unrelated syngeneic Panc02 or Panc02 GD2+ cell lines. We evaluated the kinetics of this response and observed that tumor-specific IgG was consistently detected by D22 after initiation of treatment, corresponding to a time of rapid tumor regression. The amount of tumor-specific antibody binding to tumor cells (as measured by flow MFI) did not correlate with host animal prognosis. Incubation of B16 MEL cells in DF serum, vs. naïve serum, prior to IV injection, did not delay engraftment of B16 metastases and showed similar overall survival rates. B cell depletion using anti-CD20 or anti-CD19 and anti-B220 did not impact the efficacy of ISV treatment. Thus, treatment with RT + IC + anti-CTLA-4 results in adaptive anti-tumor humoral memory response. This endogenous tumor-specific antibody response does not appear to have therapeutic efficacy but may serve as a biomarker for an anti-tumor T cell response.

Immune Checkpoint Inhibitors in Oral Cavity Squamous Cell Carcinoma and Oral Potentially Malignant Disorders: A Systematic Review

Cancers of the oral cavity cause significant cancer-related death worldwide. While survival rates have improved in recent years, new methods of treatment are being investigated to limit disease progression and to improve outcomes, particularly in oral cavity squamous cell carcinoma (OSCC) and oral potentially malignant disorders (OPMD). The emerging treatment modality of immunotherapy targets immune checkpoint molecules including PD-1 and its ligand PD-L1, CTLA-4, LAG-3, and TIM-3 to enhance the host immune response against tumours, and to limit the growth and progression of cancer cells. In this systematic review, we searched five databases for keywords pertaining to oral cancers and OPMDs, along with immune checkpoint inhibitors, in order to summarize the current status of their use and efficacy in these diseases. A total of 644 different articles were identified between 2004 and 2019, with 76 deemed suitable for inclusion in the study, providing a total of 8826 samples. Combined results show expression of PD-1 and PD-L1 in the majority of OPMD and OSCC samples, with expression correlating with increased progression and decreased survival rates. Immunotherapy agents pembrolizumab and nivolumab target PD-1 and have been shown to prolong survival rates and improve disease outcomes, especially in combination with chemotherapy or radiotherapy. Despite the equivocal nature of current evidence, there is support for the prognostic and predictive value of immune checkpoint molecules, especially PD-L1, and many studies provide support for the effective use of immune checkpoint inhibitors in the management of OSCC. Limited data is available for OPMD, therefore this should be the focus of future research.

The drug treatment research of gastrointestinal cancer in China

Gastrointestinal cancer is one of the most common cancers in China. Due to the late detection for most patients, the overall prognosis of gastrointestinal cancer is still poor. At present, the treatment of gastrointestinal cancer includes surgery, radiotherapy, ablation, chemotherapy, targeting, immunity and other treatment methods. Therefore, with the continuous improvement of individualized treatment, we hope to improve the effect of gastrointestinal cancer treatment by promoting the research progress of anti-tumor drugs. Although China's research in the field of gastrointestinal cancer drug treatment has only begun relatively recently, there has been rapid development in our progress. An increasing number of research studies led by Chinese researchers have attracted international attention, influencing clinical practices all over the world and adding to China's contribution to the global field of medicine. This article reviews China's main contributions in the clinical research of gastrointestinal cancer drugs in the past two years.

How to select IgG subclasses in developing anti-tumor therapeutic antibodies

The intact antibody of human immunoglobulin (IgG) is composed of the fragment for antigen binding (Fab) and the crystallizable fragment (Fc) for binding of Fcγ receptors. Among the four subclasses of human IgG (IgG1, IgG2, IgG3, IgG4), which differ in their constant regions, particularly in their hinges and CH2 domains, IgG1 has the highest FcγR-binding affinity, followed by IgG3, IgG2, and IgG4. As a result, different subclasses have different effector functions such as antibody-dependent cell-mediated cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP). Fcγ receptors include six subtypes (FcγRI, FcγRIIA, FcγRIIB, FcγRIIC, FcγRIIIA, FcγRIIIB) which differ in cellular distribution, binding affinity to Fc, and the resulting biological activity. Therefore, when developing anti-tumor therapeutic antibodies, including single-targeted antibodies, bi-specific antibodies (BsAbs), and antibody-drug conjugates (ADCs), many factors, such as target biology, cellular distribution of the targets, the environments of particular tumor types, as well as the proposed mechanism of action (MOA), must be taken into consideration. This review outlines fundamental strategies that are required to select IgG subclasses in developing anti-tumor therapeutic antibodies.

Immunotherapy for pancreatic cancer: A 2020 update

Pancreatic adenocarcinoma (PAC) is associated with extremely poor prognosis and remains a lethal malignancy. The main cure for PAC is surgical resection. Further treatment modalities, such as surgery, chemotherapy, radiotherapy and other locoregional therapies provide low survival rates. Currently, many clinical trials seek to assess the efficacy of immunotherapeutic strategies in PAC, including immune checkpoint inhibitors, cancer vaccines, adoptive cell transfer, combinations with other immunotherapeutic agents, chemoradiotherapy or other molecularly targeted agents; however, none of these studies have shown practice changing results. There seems to be a synergistic effect with increased response rates when a combinatorial approach of immunotherapy in conjunction with other modalities is being exploited. In this review, we illustrate the current role of immunotherapy in PAC.

Immunotherapy for esophageal cancer: a 2019 update

Esophageal cancer remains a global health concern with a dismal prognosis and an estimated 5-year survival rate of approximately 10-15%. Immunotherapy is a novel treatment approach representing an effective and promising option against several types of cancer. The development of new and efficacious immunotherapeutic strategies, such as adoptive cell therapy-based, antibody-based and vaccine-based therapies, aims to prevent immunological escape and modify immunological responses. In this review, we discuss the theoretical background and current status of immunotherapy for patients with esophageal cancer. We also present ongoing clinical trials and summarize key findings concerning survival and safety analyses.

Radiation recall dermatitis after treatment of stage IV breast cancer with nivolumab: a case report

Radiation recall dermatitis (RRD) is an uncommon dermatologic reaction provoked notably by chemotherapy in an area of skin irradiated weeks to years prior. We report a case of RRD with nivolumab in a woman with breast cancer. The patient was diagnosed with invasive ductal carcinoma of the left breast with an isolated spinal metastasis approached in an oligometastatic fashion with neoadjuvant chemotherapy, modified radical mastectomy and adjuvant radiotherapy. Unfortunately, after progression of bony metastases treated with radiotherapy, the patient received nivolumab and subsequently developed a rash corresponding to the adjuvant radiation field. This case highlights the unpredictable nature and characteristic rash of RRD. It is an important differential diagnosis for multidisciplinary teams who also see chemotherapy-induced dermatitis and immune-related adverse events.

Neurotoxicities associated with checkpoint inhibitors: Two case reports and a review of the literature

We report a case of nivolumab-induced delayed-onset aseptic meningitis and a case of limbic encephalitis and peripheral nerve palsy with toxicity relapse 6 months after initial presentation. The atypical presentations contribute to our knowledge of these rare events and reinforce the necessity for vigilant monitoring and a multidisciplinary treatment approach.