Phase I/II clinical trial of a helper peptide vaccine plus PD-1 blockade in PD-1 antibody-naïve and PD-1 antibody-experienced patients with melanoma (MEL64)

Multipeptide vaccines for melanoma in the adjuvant setting: long-term survival outcomes and post-hoc analysis of a randomized phase II trial

The critical roles of CD4+ T cells have been understudied for cancer vaccines. Here we report long-term clinical outcomes of a randomized multicenter phase II clinical trial (NCT00118274), where patients with high-risk melanoma received a multipeptide vaccine targeting CD8+ T cells (12MP) and were randomized to receive either of two vaccines for CD4+ (helper) T cells: 6MHP (6 melanoma-specific helper peptides), or tet (a nonspecific helper peptide from tetanus toxoid). Cyclophosphamide (Cy) pre-treatment was also assessed. Primary outcomes for T cell responses to 12MP, 6MHP, and tet were previously reported, suggesting immunogenicity of both vaccines but that CD8 T cell responses to 12MP were lower when tet was replaced with 6MHP. Here, in post-hoc analyses, we report durable prolongation of overall survival by adding 6MHP instead of tet. That benefit was experienced only by male patients. A favorable interaction of 6MHP and Cy is also suggested. Multivariable Cox regression analysis of the intent-to-treat population identify vaccine arm (12MP + 6MHP+Cy) and patient sex (male) as the two significant predictors of enhanced survival. These findings support the value of adding cognate T cell help to cancer vaccines and also suggest a need to assess the impact of patient sex on immune therapy outcomes.

Neoadjuvant personalized cancer vaccines: the final frontier?

INTRODUCTION

Clinical trials of personalized cancer vaccines have shown that on-demand therapies that are manufactured for each patient, result in activated T cell responses against individual tumor neoantigens. However, their use has been traditionally restricted to adjuvant settings and late-stage cancer therapy. There is growing support for the implementation of PCV earlier in the cancer therapy timeline, for reasons that will be discussed in this review.

AREAS COVERED

The efficacy of cancer vaccines may be to some extent dependent on treatment(s) given prior to vaccine administration. Tumors can undergo radical immunoediting following treatment with immunotherapies, such as checkpoint inhibitors, which may affect the presence of the very mutations targeted by cancer vaccines. This review will cover the topics of neoantigen cancer vaccines, tumor immunoediting, and therapy timing.

EXPERT OPINION

Therapy timing remains a critical topic to address in optimizing the efficacy of personalized cancer vaccines. Most personalized cancer vaccines are being evaluated in late-stage cancer patients and after treatment with checkpoint inhibitors, but they may offer a greater benefit to the patient if administered in earlier clinical settings, such as the neoadjuvant setting, where patients are not facing T cell exhaustion and/or a further compromised immune system.

Complete response of recurrent perihilar cholangiocarcinoma following sintilimab combined with lenvatinib plus S-1: a case report and review of literature

Perihilar cholangiocarcinoma is a refractory malignancy with an unfavorable prognosis and a high probability of recurrence. Systemic chemotherapy is critical for palliative treatment, but effective therapeutic strategies for perihilar cholangiocarcinoma after first-line chemotherapy failure are scarce. Here, we introduced a sustained benefit following sintilimab combined with lenvatinib plus S-1 in a patient with recurrent perihilar cholangiocarcinoma. A 52-year-old female patient was admitted to our hospital due to yellow skin and sclera, and further radiological examination revealed perihilar cholangiocarcinoma. The patient underwent surgery and histopathological results confirmed moderately differentiated adenocarcinoma with metastatic lymph nodes. Postoperative adjuvant chemotherapy with gemcitabine and S-1 was given. One year after surgery, the patient experienced hepatic recurrence. Then, she received radiofrequency ablation combined with gemcitabine and cisplatin. Unfortunately, radiological assessment revealed progressive disease with multiple liver metastases after treatment. Subsequently, she received sintilimab combined with lenvatinib plus S-1 and the lesions were completely regressed following 14 cycles of combination therapy. The patient recovered well without disease recurrence at the last follow-up. Sintilimab combined with lenvatinib plus S-1 may be an alternative therapeutic option for chemotherapy-refractory perihilar cholangiocarcinoma, and further evaluation in a larger number of patients is needed.

Prediction of survival and immunotherapy response by the combined classifier of G protein-coupled receptors and tumor microenvironment in melanoma

BACKGROUND

Melanoma is the deadliest form of skin tumor, and G protein-coupled receptors (GPCRs) play crucial roles in its carcinogenesis. Furthermore, the tumor microenvironment (TME) affects the overall survival (OS) and the response to immunotherapy. The combination of GPCRs and TME from a multi-omics perspective may help to predict the survival of the melanoma patients and their response to immunotherapy.

METHODS

Bulk-seq, single-cell RNA sequencing (scRNA-seq), gene mutations, immunotherapy responses, and clinicopathologic feature data were downloaded from public databases, and prognostic GPCRs and immune cells were screened using multiple machine learning algorithms. The expression levels of GPCRs were detected using real-time quantitative polymerase chain reaction (qPCR) in A375 and HaCaT cell lines. The GPCR-TME classifier was constructed and verified using different cohorts and multi-omics. Gene set enrichment analysis (GSEA), weighted gene co-expression network analysis (WGCNA), and tracking tumor immunophenotype (TIP) were used to identify the key biological pathways among the GPCR-TME subgroups. Then, tumor mutational burden (TMB), vital mutant genes, antigen presentation genes, and immune checkpoints were compared among the subgroups. Finally, the differences in immunotherapy response rates among the GPCR-TME subgroups were investigated.

RESULTS

A total of 12 GPCRs and five immune cell types were screened to establish the GPCR-TME classifier. No significant differences in the expression levels of the 12 GPCRs were found in the two cell lines. Patients with high GPCR score or low TME score had a poor OS; thus, the GPCRlow/TMEhigh subgroup had the most favorable OS. The scRNA-seq result revealed that immune cells had a higher GPCR score than tumor and stromal cells. The GPCR-TME classifier acted as an independent prognostic factor for melanoma. GSEA, WGCNA, and TIP demonstrated that the GPCRlow/TMEhigh subgroup was related to the activation and recruitment of anti-tumor immune cells and the positive regulation of the immune response. From a genomic perspective, the GPCRlow/TMEhigh subgroup had higher TMB, and different mutant genes. Ultimately, higher expression levels of antigen presentation genes and immune checkpoints were observed in the GPCRlow/TMEhigh subgroup, and the melanoma immunotherapy cohorts confirmed that the response rate was highest in the GPCRlow/TMEhigh cohort.

CONCLUSIONS

We have developed a GPCR-TME classifier that could predict the OS and immunotherapy response of patients with melanoma highly effectively based on multi-omics analysis.

Programmed cell death-1 blockade therapy in melanoma: Resistance mechanisms and combination strategies

Melanoma is a highly aggressive tumor derived from melanocytes. In recent years, the incidence and mortality of melanoma have gradually increased, seriously threatening human health. Classic treatments like surgery, chemotherapy, and radiotherapy show very limited efficacy. Due to the high immunogenicity of melanoma cells, immune checkpoint inhibitors have received considerable attention as melanoma treatments. One such therapy is blockade of programmed cell death-1 (PD-1), which is one of the most important negative immune regulators and is mainly expressed on activated T cells. Disruption of the interactions between PD-1 and its ligands, programmed death-ligand 1 (PD-L1) or programmed death-ligand 2 (PD-L2) rejuvenates exhausted T cells and enhances antitumor immunity. Although PD-1 blockade therapy is widely used in melanoma, a substantial proportion of patients still show no response or short durations of remission. Recent researches have focused on revealing the underlying mechanisms for resistance to this treatment and improving its efficacy through combination therapy. Here, we will introduce the resistance mechanisms associated with PD-1 blockade therapy in melanoma and review the combination therapies available.

Immunotherapy Assessment: A New Paradigm for Radiologists

Immunotherapy denotes an exemplar change in an oncological setting. Despite the effective application of these treatments across a broad range of tumors, only a minority of patients have beneficial effects. The efficacy of immunotherapy is affected by several factors, including human immunity, which is strongly correlated to genetic features, such as intra-tumor heterogeneity. Classic imaging assessment, based on computed tomography (CT) or magnetic resonance imaging (MRI), which is useful for conventional treatments, has a limited role in immunotherapy. The reason is due to different patterns of response and/or progression during this kind of treatment which differs from those seen during other treatments, such as the possibility to assess the wide spectrum of immunotherapy-correlated toxic effects (ir-AEs) as soon as possible. In addition, considering the unusual response patterns, the limits of conventional response criteria and the necessity of using related immune-response criteria are clear. Radiomics analysis is a recent field of great interest in a radiological setting and recently it has grown the idea that we could identify patients who will be fit for this treatment or who will develop ir-AEs.