Triggering co-stimulation directly in melanoma tumor fragments drives CD8+ tumor-infiltrating lymphocyte expansion with improved effector-memory properties

Machine learning-based signature of necrosis-associated lncRNAs for prognostic and immunotherapy response prediction in cutaneous melanoma and tumor immune landscape characterization

Background

Cutaneous melanoma (CM) is one of the malignant tumors with a relative high lethality. Necroptosis is a novel programmed cell death that participates in anti-tumor immunity and tumor prognosis. Necroptosis has been found to play an important role in tumors like CM. However, the necroptosis-associated lncRNAs' potential prognostic value in CM has not been identified.

Methods

The RNA sequencing data collected from The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression Project (GTEx) was utilized to identify differentially expressed genes in CM. By using the univariate Cox regression analysis and machine learning LASSO algorithm, a prognostic risk model had been built depending on 5 necroptosis-associated lncRNAs and was verified by internal validation. The performance of this prognostic model was assessed by the receiver operating characteristic curves. A nomogram was constructed and verified by calibration. Furthermore, we also performed sub-group K-M analysis to explore the 5 lncRNAs' expression in different clinical stages. Function enrichment had been analyzed by GSEA and ssGSEA. In addition, qRT-PCR was performed to verify the five lncRNAs' expression level in CM cell line (A2058 and A375) and normal keratinocyte cell line (HaCaT).

Results

We constructed a prognostic model based on five necroptosis-associated lncRNAs (AC245041.1, LINC00665, AC018553.1, LINC01871, and AC107464.3) and divided patients into high-risk group and low-risk group depending on risk scores. A predictive nomogram had been built to be a prognostic indicator to clinical factors. Functional enrichment analysis showed that immune functions had more relationship and immune checkpoints were more activated in low-risk group than that in high-risk group. Thus, the low-risk group would have a more sensitive response to immunotherapy.

Conclusion

This risk score signature could be used to divide CM patients into low- and high-risk groups, and facilitate treatment strategy decision making that immunotherapy is more suitable for those in low-risk group, providing a new sight for CM prognostic evaluation.

Adoptive tumor infiltrating lymphocyte transfer as personalized immunotherapy

Cancer is a leading cause of death worldwide and, despite new targeted therapies and immunotherapies, a large group of patients fail to respond to therapy or progress after initial response, which brings the need for additional treatment options. Manipulating the immune system using a variety of approaches has been explored for the past years with successful results. Sustained progress has been made to understand the T cell-mediated anti-tumor responses counteracting the tumorigenesis process. The T-lymphocyte pool, especially its capacity for antigen-directed cytotoxicity, has become a central focus for engaging the immune system in defeating cancer. The adoptive cell transfer of autologous tumor-infiltrating lymphocytes has been used in humans for over 30 years to treat metastatic melanoma. In this review, we provide a brief history of ACT-TIL and discuss the current state of ACT-TIL clinical development in solid tumors. We also discuss how key advances in understanding genetic intratumor heterogeneity, to accurately identify neoantigens, and new strategies designed to overcome T-cell exhaustion and tumor immunosuppression have improved the efficacy of the TIL-therapy infusion. Characteristics of the TIL products will be discussed, as well as new strategies, including the selective expansion of specific fractions from the cell product or the genetic manipulation of T cells for improving the in-vivo survival and functionality. In summary, this review outlines the potential of ACT-TIL as a personalized approach for epithelial tumors and continued discoveries are making it increasingly more effective against other types of cancers.

Therapeutic approaches targeting CD95L/CD95 signaling in cancer and autoimmune diseases

Cell death plays a pivotal role in the maintenance of tissue homeostasis. Key players in the controlled induction of cell death are the Death Receptors (DR). CD95 is a prototypic DR activated by its cognate ligand CD95L triggering programmed cell death. As a consequence, alterations in the CD95/CD95L pathway have been involved in several disease conditions ranging from autoimmune diseases to inflammation and cancer. CD95L-induced cell death has multiple roles in the immune response since it constitutes one of the mechanisms by which cytotoxic lymphocytes kill their targets, but it is also involved in the process of turning off the immune response. Furthermore, beyond the canonical pro-death signals, CD95L, which can be membrane-bound or soluble, also induces non-apoptotic signaling that contributes to its tumor-promoting and pro-inflammatory roles. The intent of this review is to describe the role of CD95/CD95L in the pathophysiology of cancers, autoimmune diseases and chronic inflammation and to discuss recently patented and emerging therapeutic strategies that exploit/block the CD95/CD95L system in these diseases.

Improved therapeutic efficacy of unmodified anti-tumor antibodies by immune checkpoint blockade and kinase targeted therapy in mouse models of melanoma

The use of specific anti-tumor antibodies has transformed the solid cancer therapeutics landscape with the relative successes of therapies such as anti-HER2 in breast cancer, and anti-EGFR in HNSCC and colorectal cancer. However, these therapies result in toxicity and the emergence of resistant tumors. Here, we showed that removing immune suppression and enhancing stimulatory signals increased the anti-tumor activity of unmodified TA99 antibodies (anti-TYRP1) with a significant reduction of growth of solid tumors and lung metastases in mouse models of melanoma. Immune checkpoint blockade enhanced the efficacy of TA99, which was associated with greater CD8⁺/Foxp3⁺, NK1.1⁺ and dendritic cell infiltrates, suggestive of an increased anti-tumor innate and adaptive immune responses. Further, MEK inhibition in melanoma cell lines increased the expression of melanosomal antigens in vitro, and combining TA99 and MEKi in vivo resulted in enhanced tumor control. Moreover, we found an improved therapeutic effect when YUMM tumor-bearing mice were treated with TA99 combined with MEKi and immune checkpoint blockade (anti-PD1 and anti-CTLA4). Our findings suggest that MEKi induced an increased expression of tumor-associated antigens, which in combination with anti-tumor antibodies, generated a robust adaptive anti-tumor response that was sustained by immune checkpoint inhibition therapy. We postulate that combining anti-tumor antibodies with standard-of-care strategies such as immune checkpoint blockade or targeted therapy, will improve therapeutic outcomes in cancer.

Generating Primary Models of Human Cancer to Aid in the Development of Clinically Relevant Oncolytic Viruses

Oncolytic viruses (OVs) represent a rapidly advancing class of cancer immunotherapeutic that is helping to shift the treatment paradigm of cancer. Initially thought to only have direct oncolysis ability, the established anticancer mechanisms of action of OVs have rapidly expanded to incorporate a multitude of immune-activating properties. Specifically, the field is focused on harnessing OVs to train patients' immune systems to recognize and eradicate cancer. Recent scientific progress has enabled the shift in focus to clinical translation, and as such it has become increasingly important to utilize clinically relevant models in the development and testing of novel OVs. As a result of this need, some research groups have developed their own experimental models derived from clinical or surgical specimens at their home institutions. This chapter outlines methodology for the generation of three distinct patient-derived experimental models. This includes cell cultures derived from (1) malignant ascites of ovarian cancer patients, (2) direct excision of metastatic melanoma, and (3) core biopsies of pancreatic cancer. Each of these methodologies has been utilized to generate replicating cellular models and have been demonstrated as valuable tools in in vitro, in vivo, and ex vivo studies.

Intratumor Adoptive Transfer of IL-12 mRNA Transiently Engineered Antitumor CD8+ T Cells

Retroviral gene transfer of interleukin-12 (IL-12) into T cells markedly enhances antitumor efficacy upon adoptive transfer but has clinically shown unacceptable severe side effects. To overcome the toxicity, we engineered tumor-specific CD8⁺ T cells to transiently express IL-12. Engineered T cells injected intratumorally, but not intravenously, led to complete rejections not only of the injected lesion but also of distant concomitant tumors. Efficacy was further enhanced by co-injection with agonist anti-CD137 mAb or by transient co-expression of CD137 ligand. This treatment induced epitope spreading of the endogenous CD8⁺ T cell immune response in a manner dependent on cDC1 dendritic cells. Mouse and human tumor-infiltrating T lymphocyte cultures can be transiently IL-12 engineered to attain marked immunotherapeutic effects.

Tumor-infiltrating lymphocytes: Streamlining a complex manufacturing process

Adoptive cell therapy of tumor-infiltrating lymphocytes has shown promise for treatment of refractory melanoma and other solid malignancies; however, challenges to manufacturing have limited its widespread use. Traditional manufacturing efforts were lengthy, cumbersome and used open culture systems. We describe changes in testing and manufacturing that decreased the process cycle time, enhanced the robustness of critical quality attribute testing and facilitated a functionally closed system. These changes have enabled export of the manufacturing process to support multi-center clinical trials.

S100A4 blockage alleviates agonistic anti-CD137 antibody-induced liver pathology without disruption of antitumor immunity

Liver-related autoimmune toxicities triggered by agonistic anti-CD137 antibodies have greatly limited their use in clinical applications. Here, we found that anti-CD137 monoclonal antibody (mAb) treatment in mice induced the infiltration of a large number of S100A4⁺ macrophages into the liver. Depletion of these cells or deficiency of S100A4 decreased inflammatory cytokine profiles and drastically reduced the number of liver pathogenic CD8⁺ T cells. Mechanistically, soluble S100A4 directly activated the Akt pathway and specifically prolonged CD8⁺ T cell survival. Interestingly, one S100A4 neutralizing mAb selectively alleviated liver abnormalities but did not affect the antitumor immunity induced by anti-CD137 mAb therapy. Thus, our study presents a novel molecular link to the liver pathology induced by an immune stimulatory antibody and proposes that combinational immunotherapies targeting those pathways could potentially elicit optimal antitumor immunity with minimal side effects.

Detection of Productively Rearranged TcR-α V-J Sequences in TCGA Exome Files: Implications for Tumor Immunoscoring and Recovery of Antitumor T-cells

Tumor immunoscoring is rapidly becoming a universal parameter of prognosis, and T-cells isolated from tumor masses are used for ex vivo amplification and readministration to patients to facilitate an antitumor immune response. We recently exploited the cancer genome atlas (TCGA) RNASeq data to assess T-cell receptor (TcR) expression and, in particular, discovered strong correlations between major histocompatibility class II (MHCII) and TcR-α constant region expression levels. In this article, we describe the results of searching TCGA exome files for TcR-α V-regions, followed by searching the V-region datasets for TcR-α-J regions. Both primary and metastatic breast cancer sample files contained recombined TcR-α V–J regions, ranging in read counts from 16–39, at the higher level. Among four such V–J rearrangements, three were productive rearrangements. Rearranged TcR-α V–J regions were also detected in TCGA–bladder cancer, –lung cancer, and –ovarian cancer datasets, as well as exome files representing bladder cancer, in Moffitt Cancer Center patients. These results suggest that a direct search of commonly available, conventional exome files for rearranged TcR segments could play a role in more sophisticated immunoscoring or in identifying particular T-cell clones and TcRs directed against tumor antigens.