At the bench: preclinical rationale for CTLA-4 and PD-1 blockade as cancer immunotherapy

Research Progress on the Role of Regulatory T Cell in Tumor Microenvironment in the Treatment of Breast Cancer

The tumor microenvironment (TME) is a complex ecosystem comprised of cancer cells, stromal cells, and immune cells. Analysis of the composition of TME is essential to assess the prognosis of patients with breast cancer (BC) and the efficacy of different regimes. Treg plays a crucial role in the microenvironment of breast cancer subtypes, and its function contributes to the development and progression of BC by suppressing anti-tumor immunity directly or indirectly through multiple mechanisms. In addition, conventional treatments, such as anthracycline-based neoadjuvant chemotherapy, and neo-therapies, such as immune-checkpoint blockades, have a significant impact on the absence of Tregs in BC TME, thus gaining additional anti-tumor effect to some extent. Strikingly, Treg in BC TME revealed the predicted efficacy of some therapeutic strategies. All these results suggest that we can manipulate the abundance of Treg to achieve the ultimate effect of both conventional and novel treatments. In this review, we discuss new insights into the characteristics of Treg in BC TME, the impact of different regiments on Treg, and the possibilities of Treg as a predictive marker of efficacy for certain treatments.

Targeting the extracellular matrix for immunomodulation: applications in drug delivery and cell therapies

Host immune cells interact bi-directionally with their extracellular matrix (ECM) to receive and deposit molecular signals, which orchestrate cellular activation, proliferation, differentiation, and function to maintain healthy tissue homeostasis. In response to pathogens or damage, immune cells infiltrate diseased sites and synthesize critical ECM molecules such as glycoproteins, proteoglycans, and glycosaminoglycans to promote healing. When the immune system misidentifies pathogens or fails to survey damaged cells effectively, maladies such as chronic inflammation, autoimmune diseases, and cancer can develop. In these conditions, it is essential to restore balance to the body through modulation of the immune system and the ECM. This review details the components of dysregulated ECM implicated in pathogenic environments and therapeutic approaches to restore tissue homeostasis. We evaluate emerging strategies to overcome inflamed, immune inhibitory, and otherwise diseased microenvironments, including mechanical stimulation, targeted proteases, adoptive cell therapy, mechanomedicine, and biomaterial-based cell therapeutics. We highlight various strategies that have produced efficacious responses in both pre-clinical and human trials and identify additional opportunities to develop next-generation interventions. Significantly, we identify a need for therapies to address dense or fibrotic tissue for the treatment of organ tissue damage and various cancer subtypes. Finally, we conclude that therapeutic techniques that disrupt, evade, or specifically target the pathogenic microenvironment have a high potential for improving therapeutic outcomes and should be considered a priority for immediate exploration. A schematic showing the various methods of extracellular matrix disruption/targeting in both fibrotic and cancerous environments. a Biomaterial-based cell therapy can be used to deliver anti-inflammatory cytokines, chemotherapeutics, or other factors for localized, slow release of therapeutics. b Mechanotherapeutics can be used to inhibit the deposition of molecules such as collagen that affect stiffness. c Ablation of the ECM and target tissue can be accomplished via mechanical degradation such as focused ultrasound. d Proteases can be used to improve the distribution of therapies such as oncolytic virus. e Localization of therapeutics such as checkpoint inhibitors can be improved with the targeting of specific ECM components, reducing off-target effects and toxicity.

Oncolytic virotherapy as promising immunotherapy against cancer: mechanisms of resistance to oncolytic viruses

Oncolytic virotherapy has currently emerged as a powerful therapeutic approach in cancer treatment. Although the history of using viruses goes back to the early 20th century, the approval of talimogene laherparepvec (T-VEC) in 2015 increased interest in oncolytic viruses (OVs). OVs are multifaceted biotherapeutic agents because they replicate in and kill tumor cells and augment immune responses by releasing immunostimulatory molecules from lysed cells. Despite promising results, some limitations hinder the efficacy of oncolytic virotherapy. The delivery challenges and the upregulation of checkpoints following oncolytic virotherapy also mediate resistance to OVs by diminishing immune responses. Furthermore, the localization of receptors of viruses in the tight junctions, interferon responses, and the aberrant expression of genes involved in the cell cycle of the virus, including their infection and replication, reduce the efficacy of OVs. In this review, we present different mechanisms of resistance to OVs and strategies to overcome them.

The Effect of miR-138 on the Function of Follicular Helper T Cells and the Differentiation of B Cells in Osteosarcoma

OBJECTIVE

To explore the effect of miR-138 on the function of follicular helper T (Tfh) cells and the differentiation of B cells in osteosarcoma.

METHODS

Clinically collect peripheral blood from osteosarcoma (OS) patients and healthy volunteers (HC), as well as OS tumor tissues (OS tumor) and adjacent tissues with normal histology (normal group). The CD4+CXCR5+Tfh cells of OS patients were screened and isolated by flow cytometry, and the expression of Tfh cell membrane surface antigens PD-1 and CTLA-4 was detected. In addition, qRT-PCR was used to detect the expression of miR-138 in tissues and Tfh cells, and the correlation relationship between miR-138 and PD-1 and CTLA-4 was analyzed. After interference or overexpression of miR-138 in Tfh cells, coculture with untreated B cells was done, and the levels of IL-10, IL-12, IL-21, and INF-γ in Tfh cell culture medium and the levels of IgM, IgG, and IgA in B cell culture medium after coculture were measured by ELISA. Flow cytometry was used to detect the expression of B cell membrane surface antigens CD27 and CD38 after coculture.

RESULTS

The rate of PD-1- and CTLA-4 positive cells in the peripheral blood and tissues of the OS group was significantly increased, the expression of miR-138 was significantly reduced, and the expression of miR-138 was negatively correlated with the expression of PD-1 and CTLA-4. In addition, upregulation of miR-138 can lead to a significant increase in the level of IL-10 in the supernatant of Tfh cells and a significant decrease in the levels of IL-12, IL-21, and INF-γ, which in turn leads to increased levels of IgM, IgG, and IgA released by B cells. At the same time, it significantly increases the rate of CD27- and CD38-positive cells and promotes the maturation of B cells. Downregulating miR-138 has the opposite effect.

CONCLUSION

Downregulating the expression of miR-138 in osteosarcoma can improve the dysfunction of CD4+CXCR5+Tfh cells and promote the differentiation of B cells.

The potential targets in immunotherapy of atherosclerosis

Cardiovascular disease is the most common cause of death, which has the highest mortality rate worldwide. Although a diverse range of inflammatory diseases can affect the cardiovascular system, however, heart failure and stroke occur due to atherosclerosis. Atherosclerosis is a chronic autoinflammatory disease of small to large vessels in which different immune mediators are involved in lipid plaque formation and inflammatory vascular remodeling process. A better understanding of the pathophysiology of atherosclerosis may lead to uncovering immunomodulatory therapies. Despite present diagnostic and therapeutic methods, the lack of immunotherapy in the prevention and treatment of atherosclerosis is perceptible. In this review, we will discuss the promising immunological-based therapeutics and novel preventive approaches for atherosclerosis. This study could provide new insights into a better perception of targeted therapeutic pathways and biological therapies.

Reconstituting Immune Surveillance in Breast Cancer: Molecular Pathophysiology and Current Immunotherapy Strategies

Over the past 50 years, breast cancer immunotherapy has emerged as an active field of research, generating novel, targeted treatments for the disease. Immunotherapies carry enormous potential to improve survival in breast cancer, particularly for the subtypes carrying the poorest prognoses. Here, we review the mechanisms by which cancer evades immune destruction as well as the history of breast cancer immunotherapies and recent developments, including clinical trials that have shaped the treatment of the disease with a focus on cell therapies, vaccines, checkpoint inhibitors, and oncolytic viruses.

Model constructions of chemosensitivity and prognosis of high grade serous ovarian cancer based on evaluation of immune microenvironment and immune response

BACKGROUND

The prognosis of high grade serous ovarian cancer (HGSOC) patients is closely related to the immune microenvironment and immune response. Based on this, the purpose of this study was to construct a model to predict chemosensitivity and prognosis, and provide novel biomarkers for immunotherapy and prognosis evaluation of HGSOC.

METHODS

GSE40595 (38 samples), GSE18520 (63 samples), GSE26712 (195 samples), TCGA (321 samples) and GTEx (88 samples) were integrated to screen differential expressed genes (DEGs) of HGSOC. The prognosis related DEGs (DEPGs) were screened through overall survival analysis. The DEGs-encoded protein-protein interaction network was constructed and hub genes of DEPGs (DEPHGs) were generated by STRING. Immune characteristics of the samples were judged by ssGSEA, ESTIMATE and CYBERSORT. TIMER was used to analyze the relationship between DEPHGs and tumor-infiltrating immunocytes, as well as the immune checkpoint genes, finally immune-related DEPHGs (IDEPHGs) were determined, and whose expression in 12 pairs of HGSOC tissues and tumor-adjacent tissues were analyzed by histological verification. Furthermore, the chemosensitivity genes in IDEPHGs were screened according to GSE15622 (n = 65). Finally, two prediction models of paclitaxel sensitivity score (PTX score) and carboplatin sensitivity score (CBP score) were constructed by lasso algorithm. The area under curve was calculated to estimate the accuracy of candidate gene models in evaluating chemotherapy sensitivity.

RESULTS

491 DEGs were screened and 37 DEGs were identified as DEPGs, and 11 DEPHGs were further identified. Among them, CXCL13, IDO1, PI3, SPP1 and TRIM22 were screened as IDEPHGs and verified in the human tissues. Further analysis showed that IDO1, PI3 and TRIM22 could independently affect the chemotherapy sensitivity of HGSOC patients. The PTX score was significantly better than TRIM22, PI3, SPP1, IDO1 and CXCL13 in predicting paclitaxel sensitivity, so was CBP score in predicting carboplatin sensitivity. What's more, both of the HGSOC patients with high PTX score or high CBP score had longer survival time.

CONCLUSIONS

Five IDEPHGs identified through comprehensive bioinformatics analysis were closely related with the prognosis, immune microenvironment and chemotherapy sensitivity of HGSOC. Two prediction models based on IDEPHGs might have potential application of chemotherapy sensitivity and prognosis for patients with HGSOC.

Applications of Magnetite Nanoparticles in Cancer Immunotherapies: Present Hallmarks and Future Perspectives

Current immuno-oncotherapeutic protocols that inhibit tumor immune evasion have demonstrated great clinical success. However, the therapeutic response is limited only to a percentage of patients, and the immune-related adverse events can compromise the therapeutic benefits. Therefore, improving cancer immunotherapeutic approaches that pursue high tumor suppression efficiency and low side effects turn out to be a clinical priority. Novel magnetite nanoparticles (MNPs) exhibit great potential for therapeutic and imaging applications by utilizing their properties of superparamagnetism, good biocompatibility, as well as the easy synthesis and modulation/functionalization. In particular, the MNPs can exert magnetic hyperthermia to induce immunogenic cell death of tumor cells for effective antigen release and presentation, and meanwhile polarize tumor-associated macrophages (TAMs) to M1 phenotype for improved tumor killing capability, thus enhancing the anti-tumor immune effects. Furthermore, immune checkpoint antibodies, immune-stimulating agents, or tumor-targeting agents can be decorated on MNPs, thereby improving their selectivity for the tumor or immune cells by the unique magnetic navigation capability of MNPs to promote the tumor killing immune therapeutics with fewer side effects. This mini-review summarizes the recent progress in MNP-based immuno-oncotherapies, including activation of macrophage, promotion of cytotoxic T lymphocyte (CTL) infiltration within tumors and modulation of immune checkpoint blockade, thus further supporting the applications of MNPs in clinical therapeutic protocols.

Immune Checkpoint Inhibitors and the Heart

Immune checkpoint inhibitors (ICIs) represent a break-through treatment for a large number of cancer types. This treatment is increasingly being recommended. ICIs are prescribed for primary tumours and for metastases, adjuvant/neo-adjuvant therapy. Thus, there is an increased need for expertise in the field, including the ways of response and toxicities related to them. ICIs become toxic because of the removal of self-tolerance, which in turn induces autoimmune processes that affect every organ. However, when relating to the heart, it has been noticed to be leading to acute heart failure and even death caused by various mechanisms, such as: myocarditis, pericarditis, arrhythmia, and Takotsubo cardiomyopathy. This review aims to address the above issues by focusing on the latest findings on the topic, by adding some insights on the mechanism of action of ICIs with a special focus on the myocardial tissue, by providing information on clinical manifestations, diagnosis and (wherever possible) treatment of the cardiotoxic events related to this therapy. The information is expanding and in many cases, the articles we found refer mainly to case-presentations and studies conducted on small populations. However, we consider that it is worthwhile to raise awareness of this new treatment, especially since it is widely now and it provides a significant increase in the survival rate in patients who receive it.

Short Review on Advances in Hydrogel-Based Drug Delivery Strategies for Cancer Immunotherapy

Cancer immunotherapy has become the new paradigm of cancer treatment. The introduction and discovery of various therapeutic agents have also accelerated the application of immunotherapy in clinical trials. However, despite the significant potency and demonstrated advantages of cancer immunotherapy, its clinical application to patients faces several safety and efficacy issues, including autoimmune reactions, cytokine release syndrome, and vascular leak syndrome-related issues. In addressing these problems, biomaterials traditionally used for tissue engineering and drug delivery are attracting attention. Among them, hydrogels can be easily injected into tumors with drugs, and they can minimize side effects by retaining immune therapeutics at the tumor site for a long time. This article reviews the status of functional hydrogels for effective cancer immunotherapy. First, we describe the basic mechanisms of cancer immunotherapy and the advantages of using hydrogels to apply these mechanisms. Next, we summarize recent advances in the development of functional hydrogels designed to locally release various immunotherapeutic agents, including cytokines, cancer immune vaccines, immune checkpoint inhibitors, and chimeric antigen receptor-T cells. Finally, we briefly discuss the current problems and possible prospects of hydrogels for effective cancer immunotherapy.

Targeting TIGIT for Immunotherapy of Cancer: Update on Clinical Development

Immune checkpoint blockers have dramatically improved the chances of survival in patients with metastatic cancer, but only a subset of the patients respond to treatment. Search for novel targets that can improve the responder rates and overcome the limitations of adverse events commonly seen with combination therapies, like PD-1 plus CTLA-4 blockade and PD-1/PD-L1 plus chemotherapy, led to the development of monoclonal antibodies blocking T-cell immunoglobulin and ITIM domain (TIGIT), a inhibitory checkpoint receptor expressed on activated T cells and NK cells. The strategy showed potential in pre-clinical and early clinical studies, and 5 molecules are now in advanced stages of evaluation (phase II and above). This review aims to provide an overview of clinical development of anti-TIGIT antibodies and describes the factors considered and thought process during early clinical development. Critical aspects that can decide the fate of clinical programs, such as origin of the antibody, Ig isotype, FCγR binding, and the dose as well as dosing schedule, are discussed along with the summary of available efficacy and safety data from clinical studies and the challenges in the development of anti-TIGIT antibodies, such as identifying patients who can benefit from therapy and getting payer coverage.

A Prognostic Autophagy-Related Gene Pair Signature and Small-Molecule Drugs for Hepatocellular Carcinoma

Dysregulation of autophagy-related genes (ARGs) is related to the prognosis of cancers. However, the aberrant expression of ARGs signature in the prognosis of hepatocellular carcinoma (HCC) remain unclear. Using The Cancer Genome Atlas and the International Cancer Genome Consortium database, 188 common autophagy-related gene pairs (ARGPs) were identified. Through univariate, least absolute shrinkage and selection operator analysis, and multivariate Cox regression analysis, a prognostic signature of the training set was constructed on the basis of 6 ARGPs. Further analysis revealed that the ARGP based signature performed more accurately in overall survival (OS) prediction compared to other published gene signatures. In addition, a high risk of HCC was closely related to CTLA4 upregulation, LC3 downregulation, low-response to axitinib, rapamycin, temsirolimus, docetaxel, metformin, and high-response to bleomycin. Univariate Cox and multivariate Cox analysis revealed that the risk score was an independent prognostic factor for HCC. These results were internally validated in the test and TCGA sets and externally validated in the ICGC set. A nomogram, consisting of the risk score and the TNM stage, performed well when compared to an ideal nomogram. In conclusion, a 6-ARGP-based prognostic signature was identified and validated as an effective predictor of OS of patients with HCC. Furthermore, we recognized six small-molecule drugs, which may be potentially effective in treating HCC.

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.

Immune checkpoint inhibitor-related hepatotoxicity: A review

The application of immune checkpoint inhibitors (ICI) in advanced cancer has been a major development in the last decade. The indications for ICIs are constantly expanding into new territory across different cancers, disease stages and lines of therapy. With this increased use, adverse events including immune checkpoint inhibitor-related hepatotoxicity (ICH) have emerged as an important clinical problem. This along with the introduction of ICI as first- and second-line treatments for advanced hepatocellular carcinoma makes ICH very relevant to gastroenterologists and hepatologists. The incidence of ICH varies between 1%-20% depending on the number, type and dose of ICI received. Investigation and management generally involve excluding differential diagnoses and following a stepwise escalation of withholding or ceasing ICI, corticosteroid treatment and adding other immunosuppressive agents depending on the severity of toxicity. The majority of patients with ICH recover and some may even safely recommence ICI therapy. Guideline recommendations are largely based on evidence derived from retrospective case series which highlights a priority for future research.

Paliperidone Inhibits Glioblastoma Growth in Mouse Brain Tumor Model and Reduces PD-L1 Expression

Simple Summary

The present study showed that a prescribed psychotropic medicine paliperidone inhibits GBM growth and prolongs survival in mouse brain tumor model and decreased the programmed death ligand 1 expression. Using the 3D co-culture also found that dopamine receptor D2 regulates the interaction of GBM-macrophage-induced PD-L1 expression in GBMs. In addition, the expression of DRD2 and PD-L1 in GBM modulates tumor-associated macrophage polarization. Our results also indicated that there is a contact-independent mechanism of PD-L1 induction in GBM upon interaction between GBM and monocytes. The present study also found that the interaction of GBM-macrophage-enhanced PD-L1 expression in GBM occurred by modulating the ERK and STAT3 signaling pathways. In addition, the inhibition of DRD2 reduces the upregulation of PD-1 expression, and it is regulating signaling in GBM.

Abstract

A previous study from our group reported that monocyte adhesion to glioblastoma (GBM) promoted tumor growth and invasion activity and increased tumor-associated macrophages (TAMs) proliferation and inflammatory mediator secretion as well. The present study showed that prescribed psychotropic medicine paliperidone reduced GBM growth and immune checkpoint protein programmed death ligand (PD-L)1 expression and increased survival in an intracranial xenograft mouse model. An analysis of the database of patients with glioma showed that the levels of PD-L1 and dopamine receptor D (DRD)2 were higher in the GBM group than in the low grade astrocytoma and non-tumor groups. In addition, GFP expressing GBM (GBM-GFP) cells co-cultured with monocytes-differentiated macrophage enhanced PD-L1 expression in GBM cells. The enhancement of PD-L1 in GBM was antagonized by paliperidone and risperidone as well as DRD2 selective inhibitor L741426. The expression of CD206 (M2 phenotype marker) was observed to be markedly increased in bone marrow-derived macrophages (BMDMs) co-cultured with GBM. Importantly, treatment with paliperidone effectively decreased CD206 and also dramatically increased CD80 (M1 phenotype marker) in BMDMs. We have previously established a PD-L1 GBM-GFP cell line that stably expresses PD-L1. Experiments showed that the expressions of CD206 was increased and CD80 was mildly decreased in the BMDMs co-cultured with PD-L1 GBM-GFP cells. On the other hands, knockdown of DRD2 expression in GBM cells dramatically decreased the expression of CD206 but markedly increased CD80 expressions in BMDMs. The present study suggests that DRD2 may be involved in regulating the PD-L1 expression in GBM and the microenvironment of GBM. Our results provide a valuable therapeutic strategy and indicate that treatments combining DRD2 antagonist paliperidone with standard immunotherapy may be beneficial for GBM treatment.

Triple Negative Breast Cancer: A Mountain Yet to Be Scaled Despite the Triumphs

Metastatic progression and tumor recurrence pertaining to TNBC are certainly the leading cause of breast cancer-related mortality; however, the mechanisms underlying TNBC chemoresistance, metastasis, and tumor relapse remain somewhat ambiguous. TNBCs show 77% of the overall 4-year survival rate compared to other breast cancer subtypes (82.7 to 92.5%). TNBC is the most aggressive subtype of breast cancer, with chemotherapy being the major approved treatment strategy. Activation of ABC transporters and DNA damage response genes alongside an enrichment of cancer stem cells and metabolic reprogramming upon chemotherapy contribute to the selection of chemoresistant cells, majorly responsible for the failure of anti-chemotherapeutic regime. These selected chemoresistant cells further lead to distant metastasis and tumor relapse. The present review discusses the approved standard of care and targetable molecular mechanisms in chemoresistance and provides a comprehensive update regarding the recent advances in TNBC management.

YIV-906 potentiated anti-PD1 action against hepatocellular carcinoma by enhancing adaptive and innate immunity in the tumor microenvironment

YIV-906 (PHY906) is a standardized botanical cancer drug candidate developed with a systems biology approach—inspired by a traditional Chinese herbal formulation, historically used to treat gastrointestinal symptoms including diarrhea, nausea and vomiting. In combination with chemotherapy and/or radiation therapy, preclinical and clinical results suggest that YIV-906 has the potential to prolong survival and improve quality of life for cancer patients. Here, we demonstrated that YIV-906 plus anti-PD1 could eradicate all Hepa 1–6 tumors in all tumor bearing mice. YIV-906 was found to have multiple mechanisms of action to enhance adaptive and innate immunity. In combination, YIV-906 reduced PD1 or counteracted PD-L1 induction caused by anti-PD1 which led to higher T-cell activation gene expression of the tumor. In addition, YIV-906 could reduce immune tolerance by modulating IDO activity and reducing monocytic MDSC of the tumor. The combination of anti-PD1 and YIV-906 generated acute inflammation in the tumor microenvironment with more M1-like macrophages. YIV-906 could potentiate the action of interferon gamma (IFNg) to increase M1-like macrophage polarization while inhibiting IL4 action to decrease M2 macrophage polarization. Flavonoids from YIV-906 were responsible for modulating IDO activity and potentiating IFNg action in M1-like macrophage polarization. In conclusion, YIV-906 could act as an immunomodulator and enhance the innate and adaptive immune response and potentiate anti-tumor activity for immunotherapies to treat cancer.

Blockade of immune checkpoints in lymph nodes through locoregional delivery augments cancer immunotherapy

Systemic administration of immune checkpoint blockade (ICB) monoclonal antibodies (mAbs) can unleash antitumor functions of T cells but is associated with variable response rates and off-target toxicities. We hypothesized that antitumor efficacy of ICB is limited by the minimal accumulation of mAb within tissues where antitumor immunity is elicited and regulated, which include the tumor microenvironment (TME) and secondary lymphoid tissues. In contrast to systemic administration, intratumoral and intradermal routes of administration resulted in higher mAb accumulation within both the TME and its draining lymph nodes (LNs) or LNs alone, respectively. The use of either locoregional administration route resulted in pronounced T cell responses from the ICB therapy, which developed in the secondary lymphoid tissues and TME of treated mice. Targeted delivery of mAb to tumor-draining lymph nodes (TdLNs) alone was associated with enhanced antitumor immunity and improved therapeutic effects compared to conventional systemic ICB therapy, and these effects were sustained at reduced mAb doses and comparable to those achieved by intratumoral administration. These data suggest that locoregional routes of administration of ICB mAb can augment ICB therapy by improving immunomodulation within TdLNs.

The Effect of Herpes Simplex Virus-Type-1 (HSV-1) Oncolytic Immunotherapy on the Tumor Microenvironment

The development of cancer causes disruption of anti-tumor immunity required for surveillance and elimination of tumor cells. Immunotherapeutic strategies aim for the restoration or establishment of these anti-tumor immune responses. Cancer immunotherapies include immune checkpoint inhibitors (ICIs), adoptive cellular therapy (ACT), cancer vaccines, and oncolytic virotherapy (OVT). The clinical success of some of these immunotherapeutic modalities, including herpes simplex virus type-1 derived OVT, resulted in Food and Drug Administration (FDA) approval for use in treatment of human cancers. However, a significant proportion of patients do not respond or benefit equally from these immunotherapies. The creation of an immunosuppressive tumor microenvironment (TME) represents an important barrier preventing success of many immunotherapeutic approaches. Mechanisms of immunosuppression in the TME are a major area of current research. In this review, we discuss how oncolytic HSV affects the tumor microenvironment to promote anti-tumor immune responses. Where possible we focus on oncolytic HSV strains for which clinical data is available, and discuss how these viruses alter the vasculature, extracellular matrix and immune responses in the tumor microenvironment.

Immune Crosstalk Between Lymph Nodes and Breast Carcinomas, With a Focus on B Cells

Lymph nodes (LNs) are highly organized secondary lymphoid organs, and reflective of immune responses to infection, injuries, or the presence of cancer. Extensive molecular and morphological analyses of immune and stromal features in tumors and LNs of breast cancer patients have revealed novel patterns indicative of disease progression. Within LNs, there are dynamic structures called germinal centers (GCs), that act as the immunological hubs for B cell development and generation of affinity matured memory B and antibody-producing plasma cells. Acting as a bridge between systemic and local immunity, associations are observed between the frequency of GCs within cancer-free LNs, the levels of stromal tumor infiltrating lymphocytes, and cancer progression. Scattered throughout the tumor microenvironment (TME) or aggregated in clusters forming tertiary lymphoid structures (TLS), the occurrence of tumor infiltrating B cells (TIL-Bs) has been linked mostly to superior disease trajectories in solid cancers. Recent TIL-Bs profiling studies have revealed a plethora of different TIL-B populations, their functional roles, and whether they are derived from GC reactions in the LN, and/or locally from GC-like structures within the TME remains to be investigated. However, parallels between the immunogenic nature of LNs as a pre-metastatic niche, TIL-B populations within the TME, and the presence of TLS will help to decipher local and widespread TIL-Bs responses and their influence on cancer progression to the lymphatics. Therapies that enhance TIL-Bs responses in the LN GC and/or in GC-like structures in the TME are thus emerging management strategies for breast and other cancer patients.

Cancer treatment-related cardiovascular disease: Current status and future research priorities

With the development of new drugs, such as molecular-targeted drugs, and multidisciplinary therapies, cancer treatment outcomes have improved, and the number of cancer survivors is increasing every year. However, some chemotherapeutic agents cause cardiovascular complications (cancer treatment-related cardiovascular disease, CTRCVD), which affect the life prognosis and quality of life (QOL) of cancer patients. Therefore, it is necessary to select treatment methods that take into account the prognosis and QOL of cancer patients, and to take measures against CTRCVD. The mechanism of cardiotoxicity of high-risk drugs, such as doxorubicin and HER2 inhibitors, are still unclear; genetic factors, and cardiovascular disease risk factors (e.g., hypertension, dyslipidemia, and diabetes) are associated with CTRCVD progression. The establishment of methods for prevention, early diagnosis, and treatment of CTRCVD and the generation of evidence for these methods are needed. It is also necessary to develop screening methods for chemotherapy cardiotoxicity. In this review, we discuss the current status of CTRCVD, its complications, and expected countermeasures.

Immune Checkpoint Inhibitors in Prostate Cancer

Simple Summary

Metastatic prostate cancer is an incurable disease with limited treatment options. Immunotherapy has demonstrated significant success in multiple cancer types but efforts to harness its benefit in prostate cancer have so far largely been unsuccessful. In this review, we analyze the preclinical rationale for the use of immunotherapy and underlying barriers preventing responses to it. We summarize clinical studies evaluating checkpoint inhibitors in prostate cancer. In the end, we review ongoing trials exploring combination immune checkpoint inhibitors in combination with other agents with the intent to modulate the immune system to improve treatment outcomes.

Abstract

Metastatic prostate cancer is a lethal disease with limited treatment options. Immune checkpoint inhibitors have dramatically changed the treatment landscape of multiple cancer types but have met with limited success in prostate cancer. In this review, we discuss the preclinical studies providing the rationale for the use of immunotherapy in prostate cancer and underlying biological barriers inhibiting their activity. We discuss the predictors of response to immunotherapy in prostate cancer. We summarize studies evaluating immune checkpoint inhibitors either as a single agent or in combination with other checkpoint inhibitors or with other agents such as inhibitors of androgen axis, poly ADP-ribose polymerase (PARP), radium-223, radiotherapy, cryotherapy, tumor vaccines, chemotherapy, tyrosine kinase inhibitors, and granulocyte-macrophage colony-stimulating factor. We thereafter review future directions including the combination of immune checkpoint blockade with inhibitors of adenosine axis, bispecific T cell engagers, PSMA directed therapies, adoptive T-cell therapy, and multiple other miscellaneous agents.

Immunotherapy for Breast Cancer Treatment

Breast cancer, as a heterogeneous disease, includes a wide range of pathological and clinical behaviors. Current treatment protocols, including radiotherapy, chemotherapy, and hormone replacement therapy, are mainly associated with poor response and high rate of recurrence. Therefore, more efforts are needed to develop alternative therapies for this type of cancer. Immunotherapy, as a novel strategy in cancer treatment, has a potential in treating breast cancer patients. Although breast cancer has long been considered problematic to treat with immunotherapy, as it is immunologically "cold," numerous newer preclinical and clinical reports now recommend that immunotherapy has the capability to treat breast cancer patients. In this review, we highlight the different immunotherapy strategies in breast cancer treatment.

Natural Killer Cells and Regulatory T Cells Cross Talk in Hepatocellular Carcinoma: Exploring Therapeutic Options for the Next Decade

Despite major advances in immunotherapy, hepatocellular carcinoma (HCC) remains a challenging target. Natural Killer (NK) cells are crucial components of the anti-HCC immune response, which can be manipulated for immunotherapeutic benefit as primary targets, modulators of the tumour microenvironment and in synchronising with tumour antigen specific effector CD8 cells for tumour clearance. Regulatory T cells shape the anti-tumour response from effector T cells via multiple suppressive mechanisms. Future research is needed to address the development of novel NK cell-targeted immunotherapy and on restraining Treg frequency and function in HCC. We have now entered a new era of anti-cancer treatment using checkpoint inhibitor (CPI)-based strategies. Combining GMP-NK cell immunotherapy to enhance the frequency of NK cells with CPI targeting both NK and CD8 T cells to release co-inhibitory receptors and enhance the cells anti-tumour immunity of HCC would be an attractive therapeutic option in the treatment of HCC. These therapeutic approaches should now be complemented by the application of genomic, proteomic and metabolomic approaches to understanding the microenvironment of HCC which, together with deep immune profiling of peripheral blood and HCC tissue before and during treatment, will provide the much-needed personalised medicine approach required to improve clinical outcomes for patients with HCC.

Safety considerations with new treatment regimens for anal cancer

Introduction: Anal cancer is a rare malignancy, but incidence rates are rising. Primary chemoradiation is the standard of care for early disease with surgery reserved for salvage. Despite success in terms of survival, patients suffer significant morbidity. Research is underway to advance the field and improve outcomes for these patients.Areas covered: This review aims to discuss the safety and efficacy of new approaches to treat anal cancer. A literature search was performed from January 1950 through November 2020 via PubMed and ClinicalTrials.gov databases to obtain data from ongoing or published studies examining new regimens for the treatment of anal cancers. Pertinent topics covered include miniature drug conjugates, epidermal growth factor receptor inhibitors, checkpoint inhibitor combinations, and novel immunomodulators.Expert opinion: Based on emerging clinical data, the treatment paradigm for anal cancer is likely to shift in the upcoming years. One of the largest areas of investigation is the field of immunotherapy, which may emerge as an integral component of anal cancer for all treatment settings.

Current strategies of virotherapy in clinical trials for cancer treatment

As a novel immune-active agent for cancer treatment, viruses have the ability of infecting and replicating in tumor cells. The safety and efficacy of viruses has been tested and confirmed in preclinical and clinical trials. In the last decade, virotherapy has been adopted as a monotherapy or combined therapy with immunotherapy, chemotherapy, or radiotherapy, showing promising outcomes against cancer. In this review, the current strategies of viruses used in clinical trials are classified and described. Besides this, the challenge and future prospects of virotherapy in the management for cancer patients are discussed in this review.

The Role of Macrophages in Cancer Development and Therapy

Macrophages are critical mediators of tissue homeostasis and influence various aspects of immunity. Tumor-associated macrophages are one of the main cellular components of the tumor microenvironment. Depending on their activation status, macrophages can exert a dual influence on tumorigenesis by either antagonizing the cytotoxic activity of immune cells or, less frequently, by enhancing antitumor responses. In most situations, TAMs suppress T cell recruitment and function or regulate other aspects of tumor immunity. The importance of TAMs targeting in cancer therapy is derived from the strong association between the high infiltration of TAMs in the tumor tissue with poor patient prognosis. Several macrophage-targeting approaches in anticancer therapy are developed, including TAM depletion, inhibition of new TAM differentiation, or re-education of TAM activation for cancer cell phagocytosis. In this review, we will describe the role of TAMs in tumor development, including such aspects as protumorigenic inflammation, immune suppression, neoangiogenesis, and enhancement of tissue invasion and distant metastasis. Furthermore, we will discuss therapeutic approaches that aim to deplete TAMs or, on the contrary, re-educate TAMs for cancer cell phagocytosis and antitumor immunity.

Co-inhibitor expression on tumor infiltrating and splenic lymphocytes after dual checkpoint inhibition in a microsatellite stable model of colorectal cancer

Checkpoint inhibitors have demonstrated clinical impact in colorectal cancer with deficient mismatch repair and high microsatellite instability. However, the majority of patients have disease with stable microsatellites that responds poorly to immunotherapies. Combinations of checkpoint inhibitors are under investigation as a way of increasing immunogenicity and promoting a robust anti-tumor immune response. The purpose of this study is to quantify the immune responses induced by mono and dual checkpoint inhibition in a mismatch repair proficient model of colorectal cancer (CRC). Tumor growth rates were monitored over time and compared between groups. We utilized fluorescence-activated cell sorting to analyze CD8⁺ and CD4⁺ T cells after treatment with either single PD-1 inhibition or dual PD-1 and CTLA-4 inhibition. Additionally, we sought to quantify the expression of co-inhibitory surface molecules PD-1, LAG3, and TIM3. Dual checkpoint inhibition was associated with a significantly slower growth rate as compared to either mono PD-1 inhibition or control (p < 0.05). Neither monotherapy nor dual checkpoint inhibition significantly affected the tumoral infiltration of lymphocytes. After treatment with dual inhibitors, infiltrating CD8⁺ T cells demonstrated significantly less expression of PD-1 (1700 vs. 2545 and 2462; p < 0.05) and LAG3 (446.2 vs. 694.4 and 707; p < 0.05) along with significantly more expression of TIM3 (12,611 vs. 2961 and 4259; p < 0.05) versus the control and anti-PD-1 groups. These results suggest that dual therapy with anti-CTLA-4 and anti-PD-1 antibodies significantly inhibits growth of microsatellite stable CRC by suppressing immunosuppressive checkpoints. Upregulation of TIM3 represents a potential escape mechanism and a target for future combination immunotherapies in CRC.

Anti-PD-L1 DNA aptamer antagonizes the interaction of PD-1/PD-L1 with antitumor effect

Tumor immune evasion enables cancer cells to escape destruction by the immune system, which causes poor prognosis and overall survival of some tumor patients. The binding of PD-L1 on tumor cells to PD-1 on T cells suppresses T cell function, and the axis is considered one of the major pathways mediating tumor cells to evade immune surveillance. The PD-L1 ligation of T cells has a profound inhibitory effect on the growth, cytokine secretion, and development of cytotoxicity. Aptamers, known as chemical antibodies, are single-stranded oligonucleotides with high affinity. In this work, we take a cell-SELEX with the engineered PD-L1-expressing cells as a target to obtain the aptamer, designated PL1, which specifically binds to PD-L1 with a Kd value of 95.73 nM, resulting in the inhibition of PD-1/PD-L1. The aptamer PL1 could restore the proliferation and IFN-γ rescue from the T cell inhibited by the PD-1/PD-L1 axis, and inhibit the growth of the CT26 colon carcinoma. The similar tumor inhibition efficacy and binding capacity of the aptamer PL1 as an antibody indicate that the aptamer PL1 can serve as an alternative therapeutic agent for cancer immunotherapy since the use of antibodies is often restricted by high cost, large size and poor tumor penetration.

PD-1 Immune Checkpoint Inhibitor Therapy Malignant Tumor Based on Monotherapy and Combined Treatment Research

Recently, immunotherapy has become the fourth pillar of cancer treatment in addition to surgery therapy, chemotherapy, and radiation therapy. The inhibitors of programed cell death protein 1 (PD-1) and its ligand PD-L1 are the new stars in immunotherapy, as they can overcome tumor immunosuppression. However, the efficacy of PD-1 inhibitors still needs to be further developed for clinical treatment. Therefore, research into treatment with anti-PD-1 drugs has emerged as a new development field. This review provides novel insights into the role and mechanism of PD-1 combination anti-tumor therapy, thereby promoting its clinical application in anti-tumor immunotherapy.

Our current understanding of checkpoint inhibitor therapy in cancer immunotherapy

OBJECTIVE

Treatments with Food and Drug Administration-approved blocking antibodies targeting inhibitory cytotoxic T lymphocyte antigen 4 (CTLA4), programmed cell death protein 1 (PD-1) receptor, or programmed cell death ligand 1 (PD-L1), collectively named checkpoint inhibitors (CPIs), have been successful in producing long-lasting remissions, even in patients with advanced-stage cancers. However, these treatments are often accompanied by undesirable autoimmune and inflammatory side effects, sometimes bringing severe consequences for the patient. Rapid expansion of clinical applications necessitates a more nuanced understanding of CPI function in health and disease to develop new strategies for minimizing the negative side effects, while preserving the immunotherapeutic benefit.

DATA SOURCES

This review summarizes a new paradigm-shifting approach to cancer immunotherapy with the focus on the mechanism of action of immune checkpoints (CTLA4, PD-1, and its ligands).

STUDY SELECTIONS

We performed a literature search and identified relevant recent clinical reports, experimental research, and review articles.

RESULTS

This review highlights our understanding of the CPI mechanism of action on cellular and molecular levels. The authors also discuss how reactivation of T cell responses through the inhibition of CTLA4, PD-1, and PD-L1 is used for tumor inhibition in cancer immunotherapy.

CONCLUSION

Mechanisms of PD-1 and CTLA4 blockade and normal biological functions of these molecules are highly complex and require additional studies that will be critical for developing new approaches to dissociate the benefits of checkpoint blockade from off-target effects of the immune reactivation that leads to immune-related adverse events.

Immunotherapy for Breast Cancer Treatment

Breast cancer, as a heterogeneous disease, includes a wide range of pathological and clinical behaviors. Current treatment protocols, including radiotherapy, chemotherapy, and hormone replacement therapy, are mainly associated with poor response and high rate of recurrence. Therefore, more efforts are needed to develop alternative therapies for this type of cancer. Immunotherapy, as a novel strategy in cancer treatment, has a potential in treating breast cancer patients. Although breast cancer has long been considered problematic to treat with immunotherapy, as it is immunologically "cold," numerous newer preclinical and clinical reports now recommend that immunotherapy has the capability to treat breast cancer patients. In this review, we highlight the different immunotherapy strategies in breast cancer treatment.

Translational cell biology of highly malignant osteosarcoma

Highly malignant osteosarcoma (HMO) is the most frequent malignant bone tumor preferentially occurring in adolescents and children with a second more flat peak in patients over the age of 60. The younger patients benefit from combined neoadjuvant chemotherapy with 65-70% 5-year survival rate. In patients with metastatic HMO the 5-year survival rate is consistently poor with approximately 30%. In the last several years strategies for target therapies have been developed by using next generation sequencing (NGS) for defining targetable molecular factors. However, it has so far been challenging to establish an effective target therapy for so-called 'orphan tumors' without recognizable driver mutations, including HMO. The molecular genetic studies using NGS have shown that HMOs are genomically unstable tumors with highly complex chaotic karyotypes. Before the background of this genetic complexity more investigations should be performed in the future for defining targetable biological factors. As the prognosis could not be improved for 40 years one may expect improvements for patients only by gaining a deeper understanding of the cell and molecular biology of HMO. The cell of origin of HMO is being clarified now. The majority of studies indicate that an osteoblastic progenitor cell is probably the cell of origin of HMO and not an undifferentiated mesenchymal stem cell. This means that the established histopathological definition of HMO through verification of osteoid production by the osteoblastic cells is well justified and will probably be the cornerstone for a precise differential diagnosis of HMO also in the years to come.

Are radiologists ready to evaluate true response to immunotherapy?

Background

Standardized response criteria for evaluating patients radiological imaging have an essential role in oncological management. Immunotherapy, using immune checkpoint inhibitors (ICIs), including drugs targeting cytotoxic T-lymphocyte-associated antigen 4 and programmed cell death protein 1 or its ligand, promise a new role that has demonstrated improvement management in cancers resistant to chemotherapy. This article reviews the literature to understand the most useful response evaluation criteria for optimal patient management under immunotherapy treatment. Areas that warrant further research are described.

Conclusion

In conclusion, ICIs have become more widely accepted and used by medical oncologists. Radiologists face challenges in assessing tumor response and becoming more involved in the management of treatment. The latest published immune-RECIST criteria can be used in response assessment, but further prospective evaluation is needed with registration clinical trials to be definitively validated.

Immune Checkpoint Molecules-Inherited Variations as Markers for Cancer Risk

In recent years, immunotherapy has been revolutionized by a new approach that works by blocking receptors called immune checkpoints (IC). These molecules play a key role in maintaining immune homeostasis, mainly by suppressing the immune response and by preventing its overactivation. Since inhibition of the immune response by IC can be used by cancer to avoid recognition and destruction by immune system, blocking them enhances the anti-tumor response. This therapeutic approach has brought spectacular clinical effects. The ICs present heterogeneous expression patterns on immune cells, which may affect the effectiveness of immunotherapy. The inherited genetic variants in regulatory regions of ICs genes can be considered as potential factors responsible for observed inter-individual differences in ICs expression levels on immune cells. Additionally, polymorphism located in exons may introduce changes to ICs amino acid sequences with potential impact on functional properties of these molecules. Since genetic variants may affect both expression and structure of ICs, they are considered as risk factors of cancer development. Inherited genetic markers such as SNPs may also be useful in stratification patients into groups which will benefit from particular immunotherapy. In this review, we have comprehensively summarized the current understanding of the relationship between inherited variations of CTLA-4, PDCD1, PD-L1, BTLA, TIM-3, and LAG-3 genes in order to select SNPs which can be used as predictive biomarkers in personalized evaluation of cancer risk development and outcomes as well as possible response to immunotherapy.

Immunogenomic Gene Signature of Cell-Death Associated Genes with Prognostic Implications in Lung Cancer

Lung cancer is one of the leading causes of death worldwide. Cell death pathways such as autophagy, apoptosis, and necrosis can provide useful clinical and immunological insights that can assist in the design of personalized therapeutics. In this study, variations in the expression of genes involved in cell death pathways and resulting infiltration of immune cells were explored in lung adenocarcinoma (The Cancer Genome Atlas: TCGA, lung adenocarcinoma (LUAD), 510 patients). Firstly, genes involved in autophagy (n = 34 genes), apoptosis (n = 66 genes), and necrosis (n = 32 genes) were analyzed to assess the prognostic significance in lung cancer. The significant genes were used to develop the cell death index (CDI) of 21 genes which clustered patients based on high risk (high CDI) and low risk (low CDI). The survival analysis using the Kaplan-Meier curve differentiated patients based on overall survival (40.4 months vs. 76.2 months), progression-free survival (26.2 months vs. 48.6 months), and disease-free survival (62.2 months vs. 158.2 months) (Log-rank test, p < 0.01). Cox proportional hazard model significantly associated patients in high CDI group with a higher risk of mortality (Hazard Ratio: H.R 1.75, 95% CI: 1.28-2.45, p < 0.001). Differential gene expression analysis using principal component analysis (PCA) identified genes with the highest fold change forming distinct clusters. To analyze the immune parameters in two risk groups, cytokines expression (n = 265 genes) analysis revealed the highest association of IL-15RA and IL 15 (> 1.5-fold, p < 0.01) with the high-risk group. The microenvironment cell-population (MCP)-counter algorithm identified the higher infiltration of CD8+ T cells, macrophages, and lower infiltration of neutrophils with the high-risk group. Interestingly, this group also showed a higher expression of immune checkpoint molecules CD-274 (PD-L1), CTLA-4, and T cell exhaustion genes (HAVCR2, TIGIT, LAG3, PDCD1, CXCL13, and LYN) (p < 0.01). Furthermore, functional enrichment analysis identified significant perturbations in immune pathways in the higher risk group. This study highlights the presence of an immunocompromised microenvironment indicated by the higher infiltration of cytotoxic T cells along with the presence of checkpoint molecules and T cell exhaustion genes. These patients at higher risk might be more suitable to benefit from PD-L1 blockade or other checkpoint blockade immunotherapies.

Small molecule inhibitors targeting the PD-1/PD-L1 signaling pathway

Tumor cells form immune escape and subsequently obtain unlimited proliferation ability due to the abnormal immune surveillance mediated by immune checkpoints. Among this class of immune checkpoints, PD-1/PD-L1 was recognized as an anticancer drug target for many years, and so far, several monoclonal antibodies have achieved encouraging outcome in cancer treatment by targeting the PD-1/PD-L1 signaling pathway. Due to the inherent limitations of antibodies, the development of small molecule inhibitors based on PD-1/PD-L1 signaling pathway is gradually reviving in decades. In this review, we summarized a number of small molecule inhibitors based on three different therapeutic approaches interfering PD-1/PD-L1 signaling pathway: (1) blocking direct interaction between PD-1 and PD-L1; (2) inhibiting transcription and translation of PD-L1; and (3) promoting degradation of PD-L1 protein. The development of these small molecule inhibitors opens a new avenue for tumor immunotherapy based on PD-1/PD-L1 signaling pathway.

MicroRNA-Assisted Hormone Cell Signaling in Colorectal Cancer Resistance

Despite substantial progress in cancer therapy, colorectal cancer (CRC) is still the third leading cause of cancer death worldwide, mainly due to the acquisition of resistance and disease recurrence in patients. Growing evidence indicates that deregulation of hormone signaling pathways and their cross-talk with other signaling cascades inside CRC cells may have an impact on therapy resistance. MicroRNAs (miRNAs) are small conserved non-coding RNAs thatfunction as negative regulators in many gene expression processes. Key studies have identified miRNA alterations in cancer progression and drug resistance. In this review, we provide a comprehensive overview and assessment of miRNAs role in hormone signaling pathways in CRC drug resistance and their potential as future targets for overcoming resistance to treatment.

Concomitant blockade of A2AR and CTLA-4 by siRNA-loaded polyethylene glycol-chitosan-alginate nanoparticles synergistically enhances antitumor T-cell responses

Inhibitory immune checkpoint (ICP) molecules are important immunosuppressive factors in a tumor microenvironment (TME). They can robustly suppress T-cell-mediated antitumor immune responses leading to cancer progression. Among the checkpoint molecules, cytotoxic T-lymphocyte-associated protein-4 (CTLA-4) is one of the critical inhibitors of anticancer T-cell responses. Besides, the expression of adenosine receptor (A2AR) on tumor-infiltrating T cells potently reduces their function. We hypothesized that concomitant silencing of these molecules in T cells might lead to enhanced antitumor responses. To examine this assumption, we purified T cells from the tumor, spleen, and local lymph nodes of CT26 colon cancer-bearing mice and suppressed the expression of A2AR and CTLA-4 using the small interfering RNA (siRNA)-loaded polyethylene glycol-chitosan-alginate (PCA) nanoparticles. The appropriate physicochemical properties of the produced nanoparticles (NPs; size of 72 nm, polydispersive index [PDI] < 0.2, and zeta potential of 11 mV) resulted in their high efficiency in transfection and suppression of target gene expression. Following the silencing of checkpoint molecules, various T-cell functions, including proliferation, apoptosis, cytokine secretion, differentiation, and cytotoxicity were analyzed, ex vivo. The results showed that the generated nanoparticles had optimal physicochemical characteristics and significantly suppressed the expression of target molecules in T cells. Moreover, a concomitant blockade of A2AR and CTLA-4 in T cells could synergistically enhance antitumor responses through the downregulation of PKA, SHP2, and PP2Aα signaling pathways. Therefore, this combination therapy can be considered as a novel promising anticancer therapeutic strategy, which should be further investigated in subsequent studies.

C-Reactive Protein and Cancer-Diagnostic and Therapeutic Insights

Cancer disease describes any pathology involving uncontrolled cell growth. As cells duplicate, they can remain localized in defined tissues, forming tumor masses and altering their microenvironmental niche, or they can disseminate throughout the body in a metastatic process affecting multiple tissues and organs. As tumors grow and metastasize, they affect normal tissue integrity and homeostasis which signals the body to trigger the acute phase inflammatory response. C-reactive protein (CRP) is a predominant protein of the acute phase response; its blood levels have long been used as a minimally invasive index of any ongoing inflammatory response, including that occurring in cancer. Its diagnostic significance in assessing disease progression or remission, however, remains undefined. By considering the recent understanding that CRP exists in multiple isoforms with distinct biological activities, a unified model is advanced that describes the relevance of CRP as a mediator of host defense responses in cancer. CRP in its monomeric, modified isoform (mCRP) modulates inflammatory responses by inserting into activated cell membranes and stimulating platelet and leukocyte responses associated with acute phase responses to tumor growth. It also binds components of the extracellular matrix in involved tissues. Conversely, CRP in its pentameric isoform (pCRP), which is the form quantified in diagnostic measurements of CRP, is notably less bioactive with weak anti-inflammatory bioactivity. Its accumulation in blood is associated with a continuous, low-level inflammatory response and is indicative of unresolved and advancing disease, as occurs in cancer. Herein, a novel interpretation of the diagnostic utility of CRP is presented accounting for the unique properties of the CRP isoforms in the context of the developing pro-metastatic tumor microenvironment.

The role of lysosomes in cancer development and progression

Lysosomes are an important component of the inner membrane system and participate in numerous cell biological processes, such as macromolecular degradation, antigen presentation, intracellular pathogen destruction, plasma membrane repair, exosome release, cell adhesion/migration and apoptosis. Thus, lysosomes play important roles in cellular activity. In addition, previous studies have shown that lysosomes may play important roles in cancer development and progression through the abovementioned biological processes and that the functional status and spatial distribution of lysosomes are closely related to cancer cell proliferation, energy metabolism, invasion and metastasis, immune escape and tumor-associated angiogenesis. Therefore, identifying the factors and mechanisms that regulate the functional status and spatial distribution of lysosomes and elucidating the relationship between lysosomes and the development and progression of cancer can provide important information for cancer diagnosis and prognosis prediction and may yield new therapeutic targets. This study briefly reviews the above information and explores the potential value of lysosomes in cancer therapy.

CD33 directed bispecific antibodies in acute myeloid leukemia

Despite the approval of a number of new targeted therapies for acute myeloid leukemia (AML), median overall survival still remains poor, ranging from 12 to 18 months in most patients. Based on the success of blinatumomab, the CD19-targeted bispecific antibody for the treatment of acute lymphoblastic leukemia, the development of several CD33-targeted bispecific antibodies for AML are being investigated in clinical trials. In this review article of CD33-targeted bispecific antibodies, we describe the rationale for targeting CD3 x CD33, summarize the data from four ongoing phase 1 studies, review the major toxicity associated with CD33-targeted bispecific antibody therapy of cytokine release syndrome (CRS) and steps to mitigate CRS, and describe possible mechanisms of resistance to CD33-targeted bispecific antibody therapy. Future development to try to improve outcomes include combination therapies to reduce the tumor burden prior to starting treatment, combining with immune checkpoint inhibition therapy such as anti-PD-1/PDL1 antibodies, and the use of second generation bispecific antibodies that target two different antigens and recruit other effector cells such as nature killer cells and macrophages.

Atractylenolide III alleviates the apoptosis through inhibition of autophagy by the mTOR-dependent pathway in alveolar macrophages of human silicosis

Silica-induced apoptosis of alveolar macrophages (AMs) is an essential part of silicosis formation. Autophagy tends to present a bidirectional effect on apoptosis. Our previous study found that the blockade of autophagy degradation might aggravate the apoptosis of AMs in human silicosis. We presume that targeting the autophagic pathway is regarded as a promising new strategy for silicosis fibrosis. As a main active component of the Atractylodes rhizome, Atractylenolide III (ATL-III) has been widely applied in clinical anti-inflammation. However, the effect and mechanism of ATL-III on autophagy in AMs of silicosis are unknown. In this study, we found that ATL-III might inhibit autophagy by mTOR-dependent manner, thereby improving the blockage of autophagic degradation in AMs. ATL-III alleviated the apoptosis of AMs in human silicosis. Furthermore, Rapamycin reversed the protective effect of ATL-III in AMs. These results indicate that ATL-III may be a potentially protective ingredient targeting autophagy for workers exposed to silica dust. These findings also suggest that inhibition of autophagy may be an effective way to alleviate the apoptosis of AMs in silicosis.

Clinical Application of Oncolytic Viruses: A Systematic Review

Leveraging the immune system to thwart cancer is not a novel strategy and has been explored via cancer vaccines and use of immunomodulators like interferons. However, it was not until the introduction of immune checkpoint inhibitors that we realized the true potential of immunotherapy in combating cancer. Oncolytic viruses are one such immunotherapeutic tool that is currently being explored in cancer therapeutics. We present the most comprehensive systematic review of all oncolytic viruses in Phase 1, 2, and 3 clinical trials published to date. We performed a systematic review of all published clinical trials indexed in PubMed that utilized oncolytic viruses. Trials were reviewed for type of oncolytic virus used, method of administration, study design, disease type, primary outcome, and relevant adverse effects. A total of 120 trials were found; 86 trials were available for our review. Included were 60 phase I trials, five phase I/II combination trials, 19 phase II trials, and two phase III clinical trials. Oncolytic viruses are feverously being evaluated in oncology with over 30 different types of oncolytic viruses being explored either as a single agent or in combination with other antitumor agents. To date, only one oncolytic virus therapy has received an FDA approval but advances in bioengineering techniques and our understanding of immunomodulation to heighten oncolytic virus replication and improve tumor kill raises optimism for its future drug development.

The Use of Immune Checkpoint Inhibitors in Oncology and the Occurrence of AKI: Where Do We Stand?

Immune checkpoint inhibitors (ICIs) are a novel class of immunotherapy drugs that have improved the treatment of a broad spectrum of cancers as metastatic melanoma, non-small lung cancer or renal cell carcinoma. These humanized monoclonal antibodies target inhibitory receptors (e.g. CTLA-4, PD-1, LAG-3, TIM-3) and ligands (PD-L1) expressed on T lymphocytes, antigen presenting cells and tumor cells and elicit an anti-tumor response by stimulating immune system. Nevertheless, the improved overall survival is complicated by the manifestation of Immune-related Adverse Effects (irAEs). During treatment with ICIs, the most common adverse kidney effect is represented by the development of acute kidney injury (AKI) with the acute tubulointerstitial nephritis as recurrent histological feature. The mechanisms involved in ICIs-induced AKI include the re-activation of effector T cells previously stimulated by nephrotoxic drugs (i.e. by antibiotics), the loss of tolerance versus self-renal antigens, the increased PD-L1 expression by tubular cells or the establishment of a pro-inflammatory milieu with the release of self-reactive antibodies. For renal transplant recipient treated with ICIs, the increased incidence of rejection is a serious concern. Therefore, the combination of ICIs with mTOR inhibitors represents an emerging strategy. Finally, it is relevant to anticipate which patients under ICIs would experience severe irAEs and from a kidney perspective, to predict patients with higher risk of AKI. Here, we provide a detailed overview of ICIs-related nephrotoxicity and the recently described multicenter studies. Several factors have been reported as biomarkers of ICIs-irAEs, in this review we speculate on potential biomarkers for ICIs-associated AKI.

Current progress and prospect of immune checkpoint inhibitors in hepatocellular carcinoma

In recent years, the incidence of liver cancer has increased and is currently the sixth most common tumor and the second leading cause of cancer-associated mortality worldwide. Most cases of liver cancer are hepatocellular carcinoma (HCC). Surgery, including liver transplantation or resection, and radiofrequency ablation therapies are all considered to be the curative treatment options for early-stage HCC. However, most patients have advanced HCC at the time of diagnosis, contributing to a poor prognosis. Therefore, improved treatment for late-stage HCC is needed. Immune checkpoint inhibitors (ICIs), among which programmed death receptor 1 (PD-1)/PD-ligand 1 and cytotoxic T lymphocyte-associated protein 4 are the representative immunological checkpoints, have shown great promise and progress for HCC treatment. The present review summarizes recent studies that have focused on ICIs and discusses the present limitations affecting the development of new therapeutic strategies.

Nicotine induces apoptosis through exacerbation of blocked alveolar macrophage autophagic degradation in silicosis

Silica dust mainly attacks alveolar macrophages (AMs). The apoptosis of AMs is correlated with the progress of silicosis. Our previous study showed that autophagic degradation was blocked in AMs from silicosis patients. However, the effects of nicotine on AM autophagy and apoptosis in silicosis are unknown. In this study, we collected AMs from twenty male workers exposed to silica and divided them into observer and silicosis patient groups, according to the tuberous pathological changes observed by X-ray. The AMs from both groups were exposed to nicotine. We found increased levels of LC3, p62, and cleaved caspase-3, decreased levels of LAMP2, and damaged lysosomes after nicotine stimulation of the AMs from both groups. We also found that the autophagy inhibitor 3-methyladenine (3MA) inhibited nicotine-induced apoptosis in the AMs. Furthermore, 3MA reversed both the nicotine-induced decrease in Bcl-2 and the increase in Bax in both groups. These results suggest that nicotine may induce apoptosis by blocking AM autophagic degradation in human silicosis.

Colorectal Cancer Immunotherapy: Options and Strategies

Colorectal cancer is the third most common cancer in the world with increasing incidence and mortality rates globally. Standard treatments for colorectal cancer have always been surgery, chemotherapy and radiotherapy which may be used in combination to treat patients. However, these treatments have many side effects due to their non-specificity and cytotoxicity toward any cells including normal cells that are growing and dividing. Furthermore, many patients succumb to relapse even after a series of treatments. Thus, it is crucial to have more alternative and effective treatments to treat CRC patients. Immunotherapy is one of the new alternatives in cancer treatment. The strategy is to utilize patients' own immune systems in combating the cancer cells. Cancer immunotherapy overcomes the issue of specificity which is the major problem in chemotherapy and radiotherapy. The normal cells with no cancer antigens are not affected. The outcomes of some cancer immunotherapy have been astonishing in some cases, but some which rely on the status of patients' own immune systems are not. Those patients who responded well to cancer immunotherapy have a better prognostic and better quality of life.