Hot and cold tumors: Immunological features and the therapeutic strategies

Unlocking cancer vaccine potential: What are the key factors?

Cancer is a global health challenge, with changing demographics and lifestyle factors producing an increasing burden worldwide. Screening advancements are enabling earlier diagnoses, but current cancer immunotherapies only induce remission in a small proportion of patients and come at a high cost. Cancer vaccines may offer a solution to these challenges, but they have been mired by poor results in past decades. Greater understanding of tumor biology, coupled with the success of vaccine technologies during the COVID-19 pandemic, has reinvigorated cancer vaccine development. With the first signs of efficacy being reported, cancer vaccines may be beginning to fulfill their potential. Solid tumors, however, present different hurdles than infectious diseases. Combining insights from previous cancer vaccine clinical development and contemporary knowledge of tumor immunology, we ask: who are the 'right' patients, what are the 'right' targets, and which are the 'right' modalities to maximize the chances of cancer vaccine success?

Targeted immunotherapy and nanomedicine for rhabdomyosarcoma: The way of the future

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma of childhood. Histology separates two main subtypes: embryonal RMS (eRMS; 60%-70%) and alveolar RMS (aRMS; 20%-30%). The aggressive aRMS carry one of two characteristic chromosomal translocations that result in the expression of a PAX3::FOXO1 or PAX7::FOXO1 fusion transcription factor; therefore, aRMS are now classified as fusion-positive (FP) RMS. Embryonal RMS have a better prognosis and are clinically indistinguishable from fusion-negative (FN) RMS. Next to histology and molecular characteristics, RMS risk groupings are now available defining low risk tumors with excellent outcomes and advanced stage disease with poor prognosis, with an overall survival of about only 20% despite intensified multimodal treatment. Therefore, development of novel effective targeted strategies to increase survival and to decrease long-term side effects is urgently needed. Recently, immunotherapies and nanomedicine have been emerging for potent and effective tumor treatments with minimal side effects, raising hopes for effective and safe cures for RMS patients. This review aims to describe the most relevant preclinical and clinical studies in immunotherapy and targeted nanomedicine performed so far in RMS and to provide an insight in future developments.

Inorganic Nanoparticle Functionalization Strategies in Immunotherapeutic Applications

Nanotechnology has been increasingly utilized in anticancer treatment owing to its ability of engineering functional nanocarriers that enhance therapeutic effectiveness while minimizing adverse effects. Inorganic nanoparticles (INPs) are prevalent nanocarriers to be customized for a wide range of anticancer applications, including theranostics, imaging, targeted drug delivery, and therapeutics, because they are advantageous for their superior biocompatibility, unique optical properties, and capacity of being modified via versatile surface functionalization strategies. In the past decades, the high adaptation of INPs in this emerging immunotherapeutic field makes them good carrier options for tumor immunotherapy and combination immunotherapy. Tumor immunotherapy requires targeted delivery of immunomodulating therapeutics to tumor locations or immunological organs to provoke immune cells and induce tumor-specific immune response while regulating immune homeostasis, particularly switching the tumor immunosuppressive microenvironment. This review explores various INP designs and formulations, and their employment in tumor immunotherapy and combination immunotherapy. We also introduce detailed demonstrations of utilizing surface engineering tactics to create multifunctional INPs. The generated INPs demonstrate the abilities of stimulating and enhancing the immune response, specific targeting, and regulating cancer cells, immune cells, and their resident microenvironment, sometimes along with imaging and tracking capabilities, implying their potential in multitasking immunotherapy. Furthermore, we discuss the promises of INP-based combination immunotherapy in tumor treatments.

Synergistic Effects of Fruquintinib Combined with Immune Checkpoint Inhibitors on Metastatic Colorectal Cancer

BACKGROUND

Fruquintinib has received approval for the management of patients with chemotherapy-resistant metastatic colorectal cancer (mCRC). However, combination of fruquintinib with immune checkpoint inhibitors (ICIs) is yet to be extensively studied. This study aims to assess the clinical efficacy, safety, and prognostic indicators of treatment regimen combining fruquintinib with ICIs in mCRC patients.

METHODS

We analyzed data from mCRC patients who were administered fruquintinib either as a monotherapy or in conjunction with ICIs following conventional chemotherapy. Parameters such as the objective response rate (ORR), disease control rate (DCR), overall survival (OS), progression-free survival (PFS), and incidence of adverse events were meticulously evaluated. Furthermore, the relationship between blood markers and patient prognosis was examined.

RESULTS

A total of 72 mCRC patients were included in this study, with a median observation period of 48 months, 19 were treated with fruquintinib alone, while 53 received a combination therapy involving fruquintinib and ICIs. The combined therapy group exhibited superior ORR and DCR compared to the fruquintinib monotherapy group. Additionally, significant improvements in OS and PFS were observed in the combined treatment group. The occurrence of adverse events was generally manageable and well-tolerated across both groups, with no significant difference in incidence rates. Notably, albumin levels were identified as a prognostic marker for PFS and OS in the univariate Cox regression analysis.

CONCLUSIONS

The combination of fruquintinib with ICIs demonstrated enhanced clinical efficacy and improved survival outcomes compared to fruquintinib monotherapy in mCRC patients. The safety of the combination regimen was deemed manageable and acceptable.

Epidemiology, Diagnostics, and Therapy of Oral Cancer-Update Review

Oral cavity and lip cancers are the 16th most common cancer in the world. It is widely known that a lack of public knowledge about precancerous lesions, oral cancer symptoms, and risk factors leads to diagnostic delay and therefore a lower survival rate. Risk factors, which include drinking alcohol, smoking, HPV infection, a pro-inflammatory factor-rich diet, and poor oral hygiene, must be known and avoided by the general population. Regular clinical oral examinations should be enriched in an oral cancer search protocol for the most common symptoms, which are summarized in this review. Moreover, new diagnostic methods, some of which are already available (vital tissue staining, optical imaging, oral cytology, salivary biomarkers, artificial intelligence, colposcopy, and spectroscopy), and newly researched techniques increase the likelihood of stopping the pathological process at a precancerous stage. Well-established oral cancer treatments (surgery, radiotherapy, chemotherapy, and immunotherapy) are continuously being developed using novel technologies, increasing their success rate. Additionally, new techniques are being researched. This review presents a novel glance at oral cancer-its current classification and epidemiology-and will provide new insights into the development of new diagnostic methods and therapies.

Analyzing the Spatial Distribution of Immune Cells in Lung Adenocarcinoma

(1) Background: This study investigates the tumor immune microenvironment, focusing on immune cell distribution in lung adenocarcinoma. (2) Methods: We evaluated fifty cases of lung adenocarcinoma, and suitable areas for further studies were annotated on the histological slides. Two tumor cores per case were obtained, one from the tumor's center and another from its periphery, and introduced into three paraffin receptor blocks for optimized processing efficiency. The 4-micrometer-thick tissue microarray sections were stained for H&E and for CD68, CD163, CD8, CD4, and PD-L1; (3) Results: Our investigation revealed significant correlations between PD-L1 expression in tumor cells and the presence of CD163+ macrophages, between CD4+ cells and CD8+, CD68+, and CD163+ cells, and also between CD8+ T cells and CD163+ cells. Additionally, while we observed some differences in cellular components and densities between the tumor center and periphery, these differences were not statistically significant. However, distinct correlations between PD-L1 and immune cells in these regions were identified, suggesting spatial heterogeneity in the immune landscape. (4) Conclusions: These results emphasize the intricate interactions between immune cells and tumor cells in lung adenocarcinoma. Understanding patient spatial immune profile could improve patient selection for immunotherapy, ensuring that those most likely to benefit are identified.

Extracellular Vesicles & Co.: scaring immune cells in the TME since ever

The health tissue surrounding a solid tumor, namely the tumor microenvironment (TME), is an extremely complex universe of cells, extracellular matrix, and signals of various nature, that support and protect the growth of cancer cells. The interactions taking place between cancer cells and the TME are crucial not only for tumor growth, invasion, and metastasis but they also play a key role in modulating immune system responses to cancer, and vice-versa. Indeed, tumor-infiltrating immune cells (e.g., T lymphocytes and natural killers) activity is greatly affected by signals (mostly ligands/receptors and paracrine) they receive in the TME, which frequently generate an immunosuppressive milieu. In the last years, it has become evident that soluble and receptor signaling is not the only way of communication between cells in the TME, with extracellular vesicles, such as exosomes, playing a central role. Among the different new kind of vesicles recently discovered, migrasomes look like to be of extreme interest as they are not only different from the others, but also have been reported as able to deliver a very heterogeneous kind of messages, able to profoundly affect recipient cells' behavior. Indeed, the role played by the different classes of extracellular vesicles, especially in the TME, relies on their not-directional diffusion from the originating cells, while migrasomes released from migrating cells do have a directional effect. Migrasomes biology and their involvement in cancer progression, dissemination, and resistance to therapy is still a largely obscure field, but with promising development foreseen in the next future.

Highlighting the role of CD44 in cervical cancer progression: immunotherapy's potential in inhibiting metastasis and chemoresistance

Cervical cancer affects thousands of women globally with recurring high-risk HPV infections being at the centre of cervical pathology. Oncological treatment strategies are continually challenged by both chemoresistance and metastasis within patients. Although both work hand-in-hand, targeting their individual mechanisms could prove highly beneficial for treatment outcomes. Such targets include the metastatic-promoting stem cell marker, CD44, which is abundant in cervical cancer cells and is common to both chemoresistance and metastatic mechanisms. Seeing that many existing advanced-stage cervical cancer treatment regimes, such as platinum-based chemotherapy regimens, remain limited and are rarely curative, alternative treatment options within the field of immunology are being considered. The use of immune checkpoint inhibition therapy, which targets immune checkpoints, CTLA-4 and PD-1/PD-L1, has shown promise as an alternate standard of care for patients suffering from advanced-stage cervical cancer. Therefore, this review aims to assess whether immune checkpoint inhibition can mitigate the pathological effects of CD44-induced EMT, metastasis, and chemoresistance in cervical cancer patients.

PD-1/PD-L1 axis: implications in immune regulation, cancer progression, and translational applications

The PD-1/PD-L1 axis is a complex signaling pathway that has an important role in the immune system cells. Programmed cell death protein 1 (PD-1) acts as an immune checkpoint on the T lymphocytes, B lymphocytes, natural killer (NK), macrophages, dendritic cells (DCs), monocytes, and myeloid cells. Its ligand, the programmed cell death 1 ligand (PD-L1), is expressed in the surface of the antigen-presenting cells (APCs). The binding of both promotes the downregulation of the T cell response to ensure the activation to prevent the onset of chronic immune inflammation. This axis in the tumor microenvironment (TME) performs a crucial role in the tumor progression and the escape of the tumor by neutralizing the immune system, the engagement of PD-L1 with PD-1 in the T cell causes dysfunctions, neutralization, and exhaustion, providing the tumor mass production. This review will provide a comprehensive overview of the functions of the PD-1/PD-L1 system in immune function, cancer, and the potential therapeutic implications of the PD-1/PD-L1 pathway for cancer management.

Identification of tumor stemness and immunity related prognostic factors and sensitive drugs in head and neck squamous cell carcinoma

The presence of cancer stem cells (CSCs) contributes significantly to treatment resistance in various cancers, including head and neck squamous cell carcinoma (HNSCC). Despite this, the relationship between cancer stemness and immunity remains poorly understood. In this study, we aimed to identify potential immunotherapeutic targets and sensitive drugs for CSCs in HNSCC. Using data from public databases, we analyzed expression patterns and prognostic values in HNSCC. The stemness index was calculated using the single-sample gene set enrichment analysis (ssgsea) algorithm, and weighted gene co-expression network analysis (WGCNA) was employed to screen for key stemness-related modules. Consensus clustering was then used to group samples for further analysis, and prognosis-related key genes were identified through regression analysis. Our results showed that tumor samples from HNSCC exhibited higher stemness indices compared to normal samples. WGCNA identified a module highly correlated with stemness, comprising 187 genes, which were significantly enriched in protein digestion and absorption pathways. Furthermore, we identified sensitive drugs targeting prognostic genes associated with tumor stemness. Notably, two genes, HLF and CCL11, were found to be highly associated with both stemness and immunity. In conclusion, our study identifies a stemness-related gene signature and promising drug candidates for CSCs of HNSCC. Additionally, HLF and CCL11, which are associated with both stemness and immunity, represent potential targets for immunotherapy in HNSCC.

ADAR-Mediated A>I(G) RNA Editing in the Genotoxic Drug Response of Breast Cancer

Epitranscriptomics is a field that delves into post-transcriptional changes. Among these modifications, the conversion of adenosine to inosine, traduced as guanosine (A>I(G)), is one of the known RNA-editing mechanisms, catalyzed by ADARs. This type of RNA editing is the most common type of editing in mammals and contributes to biological diversity. Disruption in the A>I(G) RNA-editing balance has been linked to diseases, including several types of cancer. Drug resistance in patients with cancer represents a significant public health concern, contributing to increased mortality rates resulting from therapy non-responsiveness and disease progression, representing the greatest challenge for researchers in this field. The A>I(G) RNA editing is involved in several mechanisms over the immunotherapy and genotoxic drug response and drug resistance. This review investigates the relationship between ADAR1 and specific A>I(G) RNA-edited sites, focusing particularly on breast cancer, and the impact of these sites on DNA damage repair and the immune response over anti-cancer therapy. We address the underlying mechanisms, bioinformatics, and in vitro strategies for the identification and validation of A>I(G) RNA-edited sites. We gathered databases related to A>I(G) RNA editing and cancer and discussed the potential clinical and research implications of understanding A>I(G) RNA-editing patterns. Understanding the intricate role of ADAR1-mediated A>I(G) RNA editing in breast cancer holds significant promise for the development of personalized treatment approaches tailored to individual patients' A>I(G) RNA-editing profiles.

Tumor-intrinsic IFNα and CXCL10 are critical for immunotherapeutic efficacy by recruiting and activating T lymphocytes in tumor microenvironment

Tumor immunotherapies targeting PD-(L)1 exhibit anti-tumor efficacy in only 10-30% of patients with various cancers. Literature has demonstrated that a "hot tumor" which contains high T lymphocytes in the tumor microenvironment exhibits a better response to immunotherapies than a "cold tumor." This study aimed to investigate whether tumor-intrinsic IFNα and CXCL10 determine the recruitment and activation of CD8+ T cells to become "hot tumor." In this study, we found that CXCL10 overexpressed in a variety of tumors including lung, colon, and liver tumors with a correlation with PD-L1. High PD-L1 and CXCL10 are associated with better survival rates in tumor patients receiving immunotherapies. IFNs-downstream transcriptional factor IRF-1 and STAT1 were correlated with PD-L1 and CXCL10 expression. We demonstrated that IRF-1 and STAT1 were both bound with the promoters of PD-L1 and CXCL10, sharing the same signaling pathway and determining IFNs-mediated PD-L1 and CXCL10 expression. In addition, IFNα significantly increased activation marker IFNγ in PBMCs, promoting M1 type monocyte differentiation, CD4+ T, and CD8+ T cell activation. Particularly, we found that CD8+ T lymphocytes abundantly expressed CXCR3, a receptor of CXCL10, by flow cytometry, indicating that tumor-intrinsic CXCL10 potentially recruited CD8+ T in tumor microenvironment. To demonstrate the hypothesis, immunotherapy-sensitive CT26 and immunotherapy-resistant LL/2 were used and we found that CT26 cells exhibited higher IFNα, IFNγ, CXCL10, and PD-L1 levels compared to LL/2, leading to higher IFNγ expression in mouse splenocytes. Moreover, we found that CD8+ T cells were recruited by CXCL10 in vitro, whereas SCH546738, an inhibitor of CXCR3, inhibited T cell migration and splenocytes-mediated anti-tumor effect. We then confirmed that CT26-derived tumor was sensitive to αPD-L1 immunotherapy and LL/2-tumor was resistant, whereas αPD-L1 significantly increased T lymphocyte activation marker CD107a in CT26-derived BALB/c mice. In conclusion, this study revealed that CXCL10 expression is correlated with PD-L1 in tumors, sharing the same signaling pathway and associating with better immunotherapeutic efficacy. Further evidence in the syngeneic tumor models demonstrated that immunotherapy-sensitive CT26 intrinsically exhibited higher IFNα and CXCL10 compared to immunotherapy-resistant LL/2 to recruit and activate CD8+ T cells in the tumor microenvironment, exhibiting "hot tumor" characteristic of sensitizing αPD-L1 immunotherapies.

Enhanced Proteomic Coverage in Tissue Microenvironment by Immune Cell Subtype Library-Assisted DIA-MS

Immune cells that infiltrate the tumor microenvironment (TME) play crucial roles in shaping cancer development and influencing clinical outcomes and therapeutic responses. However, obtaining a comprehensive proteomic snapshot of tumor-infiltrating immunity in clinical specimens is often hindered by small sample amounts and a low proportion of immune infiltrating cells in the TME. To enable in-depth and highly sensitive profiling of microscale tissues, we established an immune cell-enriched library-assisted strategy for data-independent acquisition mass spectrometry (DIA-MS). Firstly, six immune cell subtype-specific spectral libraries were established from sorted cluster of differentiation markers, CD8+, CD4+ T lymphocytes, B lymphocytes, natural killer cells, dendritic cells, and macrophages in murine mesenteric lymph nodes (MLNs), covering 7815 protein groups with surface markers and immune cell-enriched proteins. The feasibility of microscale immune proteomic profiling was demonstrated on 1 μg tissue protein from the tumor of murine colorectal cancer (CRC) models using single-shot DIA; the immune cell-enriched library increased coverage to quantify 7419 proteins compared to directDIA analysis (6978 proteins). The enhancement enabled the mapping of 841 immune function-related proteins and exclusive identification of many low-abundance immune proteins, such as CD1D1, and CD244, demonstrating high sensitivity for immune landscape profiling. This approach was used to characterize the MLNs in CRC models, aiming to elucidate the mechanism underlying their involvement in cancer development within the TME. Even with a low percentage of immune cell infiltration (0.25-3%) in the tumor, our results illuminate downregulation in the adaptive immune signaling pathways (such as C-type lectin receptor signaling, and chemokine signaling), T cell receptor signaling, and Th1/Th2/Th17 cell differentiation, suggesting an immunosuppressive status in MLNs of CRC model. The DIA approach using the immune cell-enriched libraries showcased deep coverage and high sensitivity that can facilitate illumination of the immune proteomic landscape for microscale samples.

Shifting cold to hot tumors by nanoparticle-loaded drugs and products

Cold tumors lack antitumor immunity and are resistant to therapy, representing a major challenge in cancer medicine. Because of the immunosuppressive spirit of the tumor microenvironment (TME), this form of tumor has a low response to immunotherapy, radiotherapy, and also chemotherapy. Cold tumors have low infiltration of immune cells and a high expression of co-inhibitory molecules, such as immune checkpoints and immunosuppressive molecules. Therefore, targeting TME and remodeling immunity in cold tumors can improve the chance of tumor repression after therapy. However, tumor stroma prevents the infiltration of inflammatory cells and hinders the penetration of diverse molecules and drugs. Nanoparticles are an intriguing tool for the delivery of immune modulatory agents and shifting cold to hot tumors. In this review article, we discuss the mechanisms underlying the ability of nanoparticles loaded with different drugs and products to modulate TME and enhance immune cell infiltration. We also focus on newest progresses in the design and development of nanoparticle-based strategies for changing cold to hot tumors. These include the use of nanoparticles for targeted delivery of immunomodulatory agents, such as cytokines, small molecules, and checkpoint inhibitors, and for co-delivery of chemotherapy drugs and immunomodulatory agents. Furthermore, we discuss the potential of nanoparticles for enhancing the efficacy of cancer vaccines and cell therapy for overcoming resistance to treatment.

Immunoregulatory cyclophilin a improves low-dose chemotherapy with a modulation of the immune tumor microenvironment in experimental models of melanoma B16 and lymphoma EL4 in vivo

PURPOSE

Different regimens of low-dose chemotherapy (LDC) are currently being actively developed and introduced into clinical practice. Along with its obvious advantages compared to conventional chemotherapy (low toxicity, prevention of drug resistance), LDC could also stimulate anti-tumor immune responses in a patient by activating effectors of innate and adaptive immunity and diminishing tumor-associated immunosuppression. As non-myeloablative, LDC could be successfully combined with different anti-cancer immunotherapeutic strategies, including immunoregulatory cytokines. Secreted cyclophilin A (CypA) is of particular interest in this respect. Previously, we showed that recombinant human CypA (rhCypA) had pleiotropic immunostimulatory activity and anti-tumor effects. Thus, rhCypA could be potentially proposed as a perspective component of combined therapy with LDC.

METHODS

In this work, we evaluated the anti-tumor effects of rhCypA combined with low doses of cyclophosphamide, doxorubicin, dacarbazine, and paclitaxel in the experimental mouse tumor models of melanoma B16 and lymphoma EL4 in vivo.

RESULTS

Synergic and potentiating effects of rhCypA combined with LDC were shown in these studies. Furthermore, as a monotherapeutic agent and a component of combined chemoimmunotherapy, rhCypA was shown to modulate the immune tumor microenvironment by enhancing tumor infiltration with macrophages, NK cells, and T cells. It was also found that rhCypA stimulated both systemic and local anti-tumor immune responses.

CONCLUSION

RhCypA could be potentially proposed as a perspective component of the combined cancer chemoimmunotherapy.

The Multifaceted Functionality of Plasmacytoid Dendritic Cells in Gastrointestinal Cancers: A Potential Therapeutic Target?

Gastrointestinal (GI) tumors pose a significant global health burden, necessitating the exploration of novel therapeutic approaches. Plasmacytoid dendritic cells (pDCs) play a crucial role in tumor immunity, exhibiting both anti-tumor and pro-tumor effects. This review aims to summarize the role of pDCs in different types of GI tumors and assess their potential as therapeutic targets. In gastric cancer, hepatocellular carcinoma, and intrahepatic cholangiocarcinoma, increased infiltration of pDCs was associated with a worse outcome, whereas in esophageal cancer, pancreatic cancer, and colorectal cancer, pDC infiltration improved the outcome. Initial animal studies of gastric cancer and hepatocellular carcinoma showed that pDCs could be a successful therapeutic target. In conclusion, pDCs play a multifaceted role in GI tumors, influencing both anti-tumor immunity and tumor progression. Further research is needed to optimize their clinical application and explore combinatorial approaches.

Nano-Delivery of Immunogenic Cell Death Inducers and Immune Checkpoint Blockade Agents: Single-Nanostructure Strategies for Enhancing Immunotherapy

Cancer immunotherapy has revolutionized oncology by harnessing the patient's immune system to target and eliminate cancer cells. However, immune checkpoint blockades (ICBs) face limitations such as low response rates, particularly in immunologically 'cold' tumors. Enhancing tumor immunogenicity through immunogenic cell death (ICD) inducers and advanced drug delivery systems represents a promising solution. This review discusses the development and application of various nanocarriers, including polymeric nanoparticles, liposomes, peptide-based nanoparticles, and inorganic nanoparticles, designed to deliver ICD inducers and ICBs effectively. These nanocarriers improve therapeutic outcomes by converting cold tumors into hot tumors, thus enhancing immune responses and reducing systemic toxicity. By focusing on single-nanoparticle systems that co-deliver both ICD inducers and ICBs, this review highlights their potential in achieving higher drug concentrations at tumor sites, improving pharmacokinetics and pharmacodynamics, and facilitating clinical translation. Future research should aim to optimize these nanocarrier systems for better in vivo performance and clinical applications, ultimately advancing cancer immunotherapy.

Beyond Anti-PD-1/PD-L1: Improving Immune Checkpoint Inhibitor Responses in Triple-Negative Breast Cancer

The introduction of anti-programmed cell death protein-1 (anti-PD-1) to the clinical management of triple-negative breast cancer (TNBC) represents a breakthrough for a disease whose treatment has long relied on the standards of chemotherapy and surgery. Nevertheless, few TNBC patients achieve a durable remission in response to anti-PD-1, and there is a need to develop strategies to maximize the potential benefit of immune checkpoint inhibition (ICI) for TNBC patients. In the present review, we discuss three conceptual strategies to improve ICI response rates in TNBC patients. The first effort involves improving patient selection. We discuss proposed biomarkers of response and resistance to anti-PD-1, concluding that an optimal biomarker will likely be multifaceted. The second effort involves identifying existing targeted therapies or chemotherapies that may synergize with ICI. In particular, we describe recent efforts to use inhibitors of the PI3K/AKT or RAS/MAPK/ERK pathways in combination with ICI. Third, considering the possibility that targeting the PD-1 axis is not the most promising strategy for TNBC treatment, we describe ongoing efforts to identify novel immunotherapy strategies.

T-cell immunity induced and reshaped by an anti-HPV immuno-oncotherapeutic lentiviral vector

We recently developed an immuno-oncotherapy against human papillomavirus (HPV)-induced tumors based on a lentiviral vector encoding the Early E6 and E7 oncoproteins of HPV16 and HPV18 genotypes, namely "Lenti-HPV-07". The robust and long-lasting anti-tumor efficacy of Lenti-HPV-07 is dependent on CD8+ T-cell induction and remodeling of the tumor microenvironment. Here, we first established that anti-vector immunity induced by Lenti-HPV-07 prime has no impact on the efficacy of a homologous boost to amplify anti-HPV T-cell immunity. To longitudinally monitor the evolution of the T-cell repertoire generated after the prime, homologous or heterologous boost with Lenti-HPV-07, we tracked T-cell clonotypes by deep sequencing of T-Cell Receptor (TCR) variable β and α chain mRNA, applied to whole peripheral blood cells (PBL) and a T cell population specific of an immunodominant E7HPV16 epitope. We observed a hyper-expansion of clonotypes post prime, accompanied by increased frequencies of HPV-07-specific T cells. Additionally, there was a notable diversification of clonotypes post boost in whole PBL, but not in the E7HPV16-specific T cells. We then demonstrated that the effector functions of such Lenti-HPV-07-induced T cells synergize with anti-checkpoint inhibitory treatments by systemic administration of anti-TIM3 or anti-NKG2A monoclonal antibodies. While Lenti-HPV-07 is about to enter a Phase I/IIa clinical trial, these results will help better elucidate its mode of action in immunotherapy against established HPV-mediated malignancies.

Immune cell related signature predicts prognosis in esophageal squamous cell carcinoma based on single-cell and bulk-RNA sequencing

Background

It has been reported that tumor immune microenvironment performs a vital role in tumor progress. However, acting mechanism of immune cell related genes (IRGs) in esophageal squamous cell carcinoma (ESCC) is uncertain.

Methods

TCGA-ESCC, GSE23400, GSE26886, GSE75241, and GSE196756 datasets were gained via public databases. First, differentially expressed genes (DEGs) between ESCC and control samples from GSE23400, GSE26886, and GSE75241 were screened out by differential expression analysis, and overlapping DEGs were identified. Single-cell transcriptome data of GSE196756 were applied to explore immune cells that might be involved in regulation of ESCC. Then, weighted gene co-expression network analysis was applied to screen IRGs. Next, differentially expressed IRGs (DE-IRGs) were identified by overlapping IRGs and DEGs, and were incorporated into univariate Cox, least absolute shrinkage and selection operator, and multivariate Cox to acquire prognosis-related genes, and ESCC samples were grouped into high-/low-risk groups on the basis of median risk score. Finally, the role of prognosis model in immunotherapy was analyzed.

Results

Totally 248 DEGs were yielded by overlapping 3,915 DEGs in GSE26886, 459 DEGs in GSE23400, and 1,641 DEGs in GSE75241. Single-cell analysis found that B cells, dendritic cells, monocytes, neutrophils, natural killer cells, and T cells were involved in ESCC development. Besides, MEred, MEblack, MEpink, MEblue and MEbrown modules were considered as key modules because of their highest correlations with immune cell subtypes. A total of 154 DE-IRGs were yielded by taking intersection of DEGs and genes in key modules. Moreover, CTSC, ALOX12, and RMND5B were identified as prognosis-related genes in ESCC. Obviously, Exclusion and TIDE scores were notably lower in high-risk group than in the other one, indicating that high-risk group was more responsive to immunotherapy.

Conclusions

Through bioinformatic analysis, we identified a prognosis model consisting of IRGs (CTSC, ALOX12, and RMND5B) in ESCC, providing new ideas for studies related to treatment and prognosis of ESCC.

Tumor-Intrinsic Enhancer of Zeste Homolog 2 Controls Immune Cell Infiltration, Tumor Growth, and Lung Metastasis in a Triple-Negative Breast Cancer Model

Triple-negative breast cancer (TNBC) is an aggressive and highly metastatic type of tumor. TNBC is often enriched in tumor-infiltrating neutrophils (TINs), which support cancer growth in part by counteracting tumor-infiltrating lymphocytes (TILs). Prior studies identified the enhancer of zeste homolog 2 (EZH2) as a pro-tumor methyltransferase in primary and metastatic TNBCs. We hypothesized that EZH2 inhibition in TNBC cells per se would exert antitumor activity by altering the tumor immune microenvironment. To test this hypothesis, we used CRISPR to generate EZH2 gene knockout (KO) and overexpressing (OE) lines from parent (wild-type-WT) 4T1 cells, an established murine TNBC model, resulting in EZH2 protein KO and OE, respectively. In vitro, EZH2 KO and OE cells showed early, transient changes in replicative capacity and invasiveness, and marked changes in surface marker profile and cytokine/chemokine secretion compared to WT cells. In vivo, EZH2 KO cells showed significantly reduced primary tumor growth and a 10-fold decrease in lung metastasis compared to WT cells, while EZH2 OE cells were unchanged. Compared to WT tumors, TIN:TIL ratios were greatly reduced in EZH2 KO tumors but unchanged in EZH2 OE tumors. Thus, EZH2 is key to 4T1 aggressiveness as its tumor-intrinsic knockout alters their in vitro secretome and in vivo primary tumor growth, TIN/TIL poise, and metastasis.

Schlafens: Emerging Therapeutic Targets

The interferon (IFN) family of immunomodulatory cytokines has been a focus of cancer research for over 50 years with direct and indirect implications in cancer therapy due to their properties to inhibit malignant cell proliferation and modulate immune responses. Among the transcriptional targets of the IFNs is a family of genes referred to as Schlafens. The products of these genes, Schlafen proteins, exert important roles in modulating cellular proliferation, differentiation, immune responses, viral replication, and chemosensitivity of malignant cells. Studies have demonstrated that abnormal expression of various Schlafens contributes to the pathophysiology of various cancers. Schlafens are now emerging as promising biomarkers and potentially attractive targets for drug development in cancer research. Here, we highlight research suggesting the use of Schlafens as cancer biomarkers and the rationale for the development of specific drugs targeting Schlafen proteins.

The Importance of HHLA2 in Solid Tumors-A Review of the Literature

Cancer immunotherapy is a rapidly developing field of medicine that aims to use the host's immune mechanisms to inhibit and eliminate cancer cells. Antibodies targeting CTLA-4, PD-1, and its ligand PD-L1 are used in various cancer therapies. However, the most thoroughly researched pathway targeting PD-1/PD-L1 has many limitations, and multiple malignancies resist its effects. Human endogenous retrovirus-H Long repeat-associating 2 (HHLA2, known as B7H5/B7H7/B7y) is the youngest known molecule from the B7 family. HHLA2/TMIGD2/KIRD3DL3 is one of the critical pathways in modulating the immune response. Recent studies have demonstrated that HHLA2 has a double effect in modulating the immune system. The connection of HHLA2 with TMIGD2 induces T cell growth and cytokine production via an AKT-dependent signaling cascade. On the other hand, the binding of HHLA2 and KIR3DL3 leads to the inhibition of T cells and mediates tumor resistance against NK cells. This review aimed to summarize novel information about HHLA2, focusing on immunological mechanisms and clinical features of the HHLA2/KIR3DL3/TMIGD2 pathway in the context of potential strategies for malignancy treatment.

Transformable Supramolecular Self-Assembled Peptides for Cascade Self-Enhanced Ferroptosis Primed Cancer Immunotherapy

Immunotherapy has received widespread attention for its effective and long-term tumor-eliminating ability. However, for immunogenic "cold" tumors, such as prostate cancer (PCa), the low immunogenicity of the tumor itself is a serious obstacle to efficacy. Here, this work reports a strategy to enhance PCa immunogenicity by triggering cascade self-enhanced ferroptosis in tumor cells, turning the tumor from "cold" to "hot". This work develops a transformable self-assembled peptide TEP-FFG-CRApY with alkaline phosphatase (ALP) responsiveness and glutathione peroxidase 4 (GPX4) protein targeting. TEP-FFG-CRApY self-assembles into nanoparticles under aqueous conditions and transforms into nanofibers in response to ALP during endosome/lysosome uptake into tumor cells, promoting lysosomal membrane permeabilization (LMP). On the one hand, the released TEP-FFG-CRAY nanofibers target GPX4 and selectively degrade the GPX4 protein under the light irradiation, inducing ferroptosis; on the other hand, the large amount of leaked Fe2+ further cascade to amplify the ferroptosis through the Fenton reaction. TEP-FFG-CRApY-induced immunogenic ferroptosis improves tumor cell immunogenicity by promoting the maturation of dendritic cells (DCs) and increasing intratumor T-cell infiltration. More importantly, recovered T cells further enhance ferroptosis by secreting large amounts of interferon-gamma (IFN-γ). This work provides a novel strategy for the molecular design of synergistic molecularly targeted therapy for immunogenic "cold" tumors.

Iridium(III)-Based PD-L1 Agonist Regulates p62 and ATF3 for Enhanced Cancer Immunotherapy

Anti-PD-L1 immunotherapy, a new lung cancer treatment, is limited to a few patients due to low PD-L1 expression and tumor immunosuppression. To address these challenges, the upregulation of PD-L1 has the potential to elevate the response rate and efficiency of anti-PD-L1 and alleviate the immunosuppression of the tumor microenvironment. Herein, we developed a novel usnic acid-derived Iridium(III) complex, Ir-UA, that boosts PD-L1 expression and converts "cold tumors" to "hot". Subsequently, we administered Ir-UA combined with anti-PD-L1 in mice, which effectively inhibited tumor growth and promoted CD4+ and CD8+ T cell infiltration. To our knowledge, Ir-UA is the first iridium-based complex to stimulate the expression of PD-L1 by explicitly regulating its transcription factors, which not only provides a promising platform for immune checkpoint blockade but, more importantly, provides an effective treatment strategy for patients with low PD-L1 expression.

Microphysiological systems as models for immunologically 'cold' tumors

The tumor microenvironment (TME) is a diverse milieu of cells including cancerous and non-cancerous cells such as fibroblasts, pericytes, endothelial cells and immune cells. The intricate cellular interactions within the TME hold a central role in shaping the dynamics of cancer progression, influencing pivotal aspects such as tumor initiation, growth, invasion, response to therapeutic interventions, and the emergence of drug resistance. In immunologically 'cold' tumors, the TME is marked by a scarcity of infiltrating immune cells, limited antigen presentation in the absence of potent immune-stimulating signals, and an abundance of immunosuppressive factors. While strategies targeting the TME as a therapeutic avenue in 'cold' tumors have emerged, there is a pressing need for novel approaches that faithfully replicate the complex cellular and non-cellular interactions in order to develop targeted therapies that can effectively stimulate immune responses and improve therapeutic outcomes in patients. Microfluidic devices offer distinct advantages over traditional in vitro 3D co-culture models and in vivo animal models, as they better recapitulate key characteristics of the TME and allow for precise, controlled insights into the dynamic interplay between various immune, stromal and cancerous cell types at any timepoint. This review aims to underscore the pivotal role of microfluidic systems in advancing our understanding of the TME and presents current microfluidic model systems that aim to dissect tumor-stromal, tumor-immune and immune-stromal cellular interactions in various 'cold' tumors. Understanding the intricacies of the TME in 'cold' tumors is crucial for devising effective targeted therapies to reinvigorate immune responses and overcome the challenges of current immunotherapy approaches.

Patient-derived tumoroids and proteomic signatures: tools for early drug discovery

Onco-virotherapy is an emergent treatment for cancer based on viral vectors. The therapeutic activity is based on two different mechanisms including tumor-specific oncolysis and immunostimulatory properties. In this study, we evaluated onco-virotherapy in vitro responses on immunocompetent non-small cell lung cancer (NSCLC) patient-derived tumoroids (PDTs) and healthy organoids. PDTs are accurate tools to predict patient's clinical responses at the in vitro stage. We showed that onco-virotherapy could exert specific antitumoral effects by producing a higher number of viral particles in PDTs than in healthy organoids. In the present work, we used multiplex protein screening, based on proximity extension assay to highlight different response profiles. Our results pointed to the increase of proteins implied in T cell activation, such as IFN-γ following onco-virotherapy treatment. Based on our observation, oncolytic viruses-based therapy responders are dependent on several factors: a high PD-L1 expression, which is a biomarker of greater immune response under immunotherapies, and the number of viral particles present in tumor tissue, which is dependent to the metabolic state of tumoral cells. Herein, we highlight the use of PDTs as an alternative in vitro model to assess patient-specific responses to onco-virotherapy at the early stage of the preclinical phases.

New avenues for the treatment of immunotherapy-resistant pancreatic cancer

Pancreatic cancer (PC) is characterized by its extremely aggressive nature and ranks 14th in the number of new cancer cases worldwide. However, due to its complexity, it ranks 7th in the list of the most lethal cancers worldwide. The pathogenesis of PC involves several complex processes, including familial genetic factors associated with risk factors such as obesity, diabetes mellitus, chronic pancreatitis, and smoking. Mutations in genes such as KRAS, TP53, and SMAD4 are linked to the appearance of malignant cells that generate pancreatic lesions and, consequently, cancer. In this context, some therapies are used for PC, one of which is immunotherapy, which is extremely promising in various other types of cancer but has shown little response in the treatment of PC due to various resistance mechanisms that contribute to a drop in immunotherapy efficiency. It is therefore clear that the tumor microenvironment (TME) has a huge impact on the resistance process, since cellular and non-cellular elements create an immunosuppressive environment, characterized by a dense desmoplastic stroma with cancer-associated fibroblasts, pancreatic stellate cells, extracellular matrix, and immunosuppressive cells. Linked to this are genetic mutations in TP53 and immunosuppressive factors that act on T cells, resulting in a shortage of CD8+ T cells and limited expression of activation markers such as interferon-gamma. In this way, finding new strategies that make it possible to manipulate resistance mechanisms is necessary. Thus, techniques such as the use of TME modulators that block receptors and stromal molecules that generate resistance, the use of genetic manipulation in specific regions, such as microRNAs, the modulation of extrinsic and intrinsic factors associated with T cells, and, above all, therapeutic models that combine these modulation techniques constitute the promising future of PC therapy. Thus, this study aims to elucidate the main mechanisms of resistance to immunotherapy in PC and new ways of manipulating this process, resulting in a more efficient therapy for cancer patients and, consequently, a reduction in the lethality of this aggressive cancer.

Advancements in Stimulus-Responsive Co-Delivery Nanocarriers for Enhanced Cancer Immunotherapy

Cancer immunotherapy has emerged as a novel therapeutic approach against tumors, with immune checkpoint inhibitors (ICIs) making significant clinical practice. The traditional ICIs, PD-1 and PD-L1, augment the cytotoxic function of T cells through the inhibition of tumor immune evasion pathways, ultimately leading to the initiation of an antitumor immune response. However, the clinical implementation of ICIs encounters obstacles stemming from the existence of an immunosuppressive tumor microenvironment and inadequate infiltration of CD8+T cells. Considerable attention has been directed towards advancing immunogenic cell death (ICD) as a potential solution to counteract tumor cell infiltration and the immunosuppressive tumor microenvironment. This approach holds promise in transforming "cold" tumors into "hot" tumors that exhibit responsiveness to antitumor. By combining ICD with ICIs, a synergistic immune response against tumors can be achieved. However, the combination of ICD inducers and PD-1/PD-L1 inhibitors is hindered by issues such as poor targeting and uncontrolled drug release. An advantageous solution presented by stimulus-responsive nanocarrier is integrating the physicochemical properties of ICD inducers and PD-1/PD-L1 inhibitors, facilitating precise delivery to specific tissues for optimal combination therapy. Moreover, these nanocarriers leverage the distinct features of the tumor microenvironment to accomplish controlled drug release and regulate the kinetics of drug delivery. This article aims to investigate the advancement of stimulus-responsive co-delivery nanocarriers utilizing ICD and PD-1/PD-L1 inhibitors. Special focus is dedicated to exploring the advantages and recent advancements of this system in enabling the combination of ICIs and ICD inducers. The molecular mechanisms of ICD and ICIs are concisely summarized. In conclusion, we examine the potential research prospects and challenges that could greatly enhance immunotherapeutic approaches for cancer treatment.

Engineering transcriptional regulation for cell-based therapies

A major aim in the field of synthetic biology is developing tools capable of responding to user-defined inputs by activating therapeutically relevant cellular functions. Gene transcription and regulation in response to external stimuli are some of the most powerful and versatile of these cellular functions being explored. Motivated by the success of chimeric antigen receptor (CAR) T-cell therapies, transmembrane receptor-based platforms have been embraced for their ability to sense extracellular ligands and to subsequently activate intracellular signal transduction. The integration of transmembrane receptors with transcriptional activation platforms has not yet achieved its full potential. Transient expression of plasmid DNA is often used to explore gene regulation platforms in vitro. However, applications capable of targeting therapeutically relevant endogenous or stably integrated genes are more clinically relevant. Gene regulation may allow for engineered cells to traffic into tissues of interest and secrete functional proteins into the extracellular space or to differentiate into functional cells. Transmembrane receptors that regulate transcription have the potential to revolutionize cell therapies in a myriad of applications, including cancer treatment and regenerative medicine. In this review, we will examine current engineering approaches to control transcription in mammalian cells with an emphasis on systems that can be selectively activated in response to extracellular signals. We will also speculate on the potential therapeutic applications of these technologies and examine promising approaches to expand their capabilities and tighten the control of gene regulation in cellular therapies.

CKLF instigates a "cold" microenvironment to promote MYCN-mediated tumor aggressiveness

Solid tumors, especially those with aberrant MYCN activation, often harbor an immunosuppressive microenvironment to fuel malignant growth and trigger treatment resistance. Despite this knowledge, there are no effective strategies to tackle this problem. We found that chemokine-like factor (CKLF) is highly expressed by various solid tumor cells and transcriptionally up-regulated by MYCN. Using the MYCN-driven high-risk neuroblastoma as a model system, we demonstrated that as early as the premalignant stage, tumor cells secrete CKLF to attract CCR4-expressing CD4+ cells, inducing immunosuppression and tumor aggression. Genetic depletion of CD4+ T regulatory cells abolishes the immunorestrictive and protumorigenic effects of CKLF. Our work supports that disrupting CKLF-mediated cross-talk between tumor and CD4+ suppressor cells represents a promising immunotherapeutic approach to battling MYCN-driven tumors.

High hypoxia status in pancreatic cancer is associated with multiple hallmarks of an immunosuppressive tumor microenvironment

Introduction

Pancreatic ductal adenocarcinoma (PDAC), the most common form of pancreatic cancer, is a particularly lethal disease that is often diagnosed late and is refractory to most forms of treatment. Tumour hypoxia is a key hallmark of PDAC and is purported to contribute to multiple facets of disease progression such as treatment resistance, increased invasiveness, metabolic reprogramming, and immunosuppression.

Methods

We used the Buffa gene signature as a hypoxia score to profile transcriptomics datasets from PDAC cases. We performed cell-type deconvolution and gene expression profiling approaches to compare the immunological phenotypes of cases with low and high hypoxia scores. We further supported our findings by qPCR analyses in PDAC cell lines cultured in hypoxic conditions.

Results

First, we demonstrated that this hypoxia score is associated with increased tumour grade and reduced survival suggesting that this score is correlated to disease progression. Subsequently, we compared the immune phenotypes of cases with high versus low hypoxia score expression (HypoxiaHI vs. HypoxiaLOW) to show that high hypoxia is associated with reduced levels of T cells, NK cells and dendritic cells (DC), including the crucial cDC1 subset. Concomitantly, immune-related gene expression profiling revealed that compared to HypoxiaLOW tumours, mRNA levels for multiple immunosuppressive molecules were notably elevated in HypoxiaHI cases. Using a Random Forest machine learning approach for variable selection, we identified LGALS3 (Galectin-3) as the top gene associated with high hypoxia status and confirmed its expression in hypoxic PDAC cell lines.

Discussion

In summary, we demonstrated novel associations between hypoxia and multiple immunosuppressive mediators in PDAC, highlighting avenues for improving PDAC immunotherapy by targeting these immune molecules in combination with hypoxia-targeted drugs.

Is Immunotherapy Beneficial in Patients with Oncogene-Addicted Non-Small Cell Lung Cancers? A Narrative Review

Over the past 20 years, there has been a paradigm shift in the care of patients with non-small cell lung cancer (NSCLC), who now have a range of systemic treatment options including targeted therapy, chemotherapy, immunotherapy (ICI), and antibody-drug conjugates (ADCs). A proportion of these cancers have single identifiable alterations in oncogenes that drive their proliferation and cancer progression, known as "oncogene-addiction". These "driver alterations" are identified in approximately two thirds of patients with lung adenocarcinomas, via next generation sequencing or other orthogonal tests. It was noted in the early clinical development of ICIs that patients with oncogene-addicted NSCLC may have differential responses to ICI. The toxicity signal for patients with oncogene-addicted NSCLC when treated with ICIs also seemed to differ depending on the alteration present and the specific targeted agent used. Developing a greater understanding of the underlying reasons for these clinical observations has become an important area of research in NSCLC. In this review, we analyze the efficacy and safety of ICI according to specific mutations, and consider possible future directions to mitigate safety concerns and improve the outcomes for patients with oncogene-addicted NSCLC.

Matched analysis of detailed peripheral blood and tumor immune microenvironment profiles in bladder cancer

Background: Bladder cancer and therapy responses hinge on immune profiles in the tumor microenvironment (TME) and blood, yet studies linking tumor-infiltrating immune cells to peripheral immune profiles are limited. Methods: DNA methylation cytometry quantified TME and matched peripheral blood immune cell proportions. With tumor immune profile data as the input, subjects were grouped by immune infiltration status and consensus clustering. Results: Immune hot and cold groups had different immune compositions in the TME but not in circulating blood. Two clusters of patients identified with consensus clustering had different immune compositions not only in the TME but also in blood. Conclusion: Detailed immune profiling via methylation cytometry reveals the significance of understanding tumor and systemic immune relationships in cancer patients.

Comparison of the effectiveness of integrative immunomodulatory treatments and conventional therapies on the survival of selected gastrointestinal cancer patients

In the last decade, the use of immunomodulating treatments (IMT) at integrative oncology providers (IOP) increased. IMTs are used to modulate the tumor microenvironment, which might lead to increased response-to-treatment, and the indication of immune checkpoint inhibitors might also be widened. The efficacy and safety of IMTs in advanced/metastatic gastrointestinal cancers were compared with conventional chemo(radio)therapy (CT). 21 colorectal- (CRC), 14 pancreatic- (PC), 5 cholangiocellular- (CCC), 5 gastric- (GC) and 4 esophageal cancer (EC) patients received IMT. IMT and CT were compared in CRC and PC. CT was administered at an academic oncology center. After the initiation of IMT, a median survival of ~ 20 (CRC, PC and EC) and ~ 10 months (CCC and GC) was observed. Of the IMTs, locoregional modulated electro-hyperthermia had the most positive effect on overall survival (HR: 0.3055; P = 0.0260), while fever-inducing interleukin-2, and low-dose ipilimumab showed a positive tendency. IMT was superior to CT in PC (HR: 0.1974; P = 0.0013), while modest effect was detected in CRC (HR: 0.7797; P = 0.4710). When the whole study population was analyzed, IMTs showed minimal effect on patient survival, still CT had the greatest effect if introduced as early as possible (HR: 0.0624; P < 0.0001). The integrative IMTs in the presented form have mild impact on gastrointestinal cancer patients' survival, however, we observed its benefit in PC, which warrants further investigations.