The impact of BRAF mutation status on clinical outcomes with anti-PD-1 monotherapy versus combination ipilimumab/nivolumab in treatment-naïve advanced stage melanoma

Bifidobacterium modulation of tumor immunotherapy and its mechanism

The advent of tumor immunotherapy in patients has revolutionized the treatment of tumors and significantly improved survival rates for a wide range of tumors. However, the full therapeutic potential of immune checkpoint inhibitors (ICIs) has yet to be realized, as not all patients have a lasting survival benefit from them, and a significant proportion of patients show primary or acquired resistance to immunotherapy. Bifidobacterium is one of the most common probiotics, and its antitumor and immunomodulatory effects have been demonstrated in recent years, but its immunomodulatory effects in tumors, especially on ICIs and in combination, have not been extensively studied in clinical practice, and its effects on the immune system and the mechanisms that modulate immunotherapy are largely unknown. Therefore, this review will focus on the immunomodulatory effects of Bifidobacteria in malignancies and the possible mechanisms of action of Bifidobacteria on immunotherapy in the hope of providing a basis for further research and better application of Bifidobacteria in clinical practice.

Emerging prognostic biomarkers in advanced cutaneous melanoma: a literature update

INTRODUCTION

Over the past two years, the scientific community has witnessed an exponential growth in research focused on identifying prognostic biomarkers for melanoma, both in pre-clinical and clinical settings. This surge in studies reflects the need of developing effective prognostic indicators in the field of melanoma.

AREAS COVERED

The aim of this work is to review the scientific literature on the most recent findings on the development or validation of prognostic biomarkers in melanoma, in the attempt of providing both clinicians and researchers with an updated broad synopsis of prognostic biomarkers in cutaneous melanoma.

EXPERT OPINION

While the field of prognostic biomarkers in melanoma appears promising, there are several complexities and limitations to address. The interdependence of clinical, histological, and molecular features requires accurate classification of different biomarker families. Correlation does not imply causation, and adjustments for confounding factors are often overlooked. In this scenario, large-scale studies based on high-quality clinical trial data can provide more reliable evidence. It is essential to avoid oversimplification by focusing on a single biomarker, as the interactions among multiple factors contribute to define the disease course and patient's outcome. Furthermore, implementing well-supported evidence in real-life settings can help advance prognostic biomarker research in melanoma.

Efficacy and safety of the combined use of ipilimumab and nivolumab for melanoma patients with brain metastases: a systematic review and meta-analysis

CONTEXT

Immune checkpoint inhibitors have advanced immunotherapy for melanoma patients.Objective: This study evaluates efficacy and safety of ipilimumab and nivolumab combination (IN) for melanoma brain metastases (MBM) patients.

MATERIALS AND METHODS

Literature search was conducted in electronic databases and studies were included if they reported efficacy and safety of IN in MBM patients or prognostic information related to brain metastases. Outcomes evaluated were objective response rate (ORR), complete remission/stable disease/progressive disease rates, progression-free survival (PFS), overall survival (OS), incidence rates of adverse events, and hazard ratios of disease progression or mortality between IN-treated patients with and without brain metastasis.

RESULTS

Intracranial ORR was higher in IN-treated MBM patients than with control therapies (nivolumab or ipilimumab plus fotemustine). IN treatment led to longer PFS and OS in than control treatments. Five-year OS of IN-treated MBM patients was up to 51% compared to 34% for nivolumab. Outcomes were better for treatment naïve and asymptomatic patients. Whereas many studies reported significantly higher mortality or progression risk with IN treatment in MBM patients compared to non-MBM melanoma patients, many others did not find this risk significant. Incidence of grade 3/4 adverse events in IN-treated MBM patients was: diarrhea or colitis (16%), hepatitis (15%), rash (8%), increased alanine transaminase (8%), increased aspartate aminotransferase (7%), increased lipase (6%), increased amylase (4%), fatigue (3%), hypophysitis (2%), pneumonitis (2%), headache (2%), nausea or vomiting (1%), and neutropenia (1%).

CONCLUSION

IN is an efficacious and safer treatment option for MBM patients, especially for asymptomatic and treatment naïve patients.

A real-world study of adjuvant anti-PD -1 immunotherapy on stage III melanoma with BRAF, NRAS, and KIT mutations

BACKGROUND

Melanoma frequently harbors BRAF, NRAS, or KIT mutations which influence both tumor development and treatment strategies. For example, it is still controversial whether adjuvant anti-PD-1 monotherapy or BRAF/MEK inhibitors may better improve the survival for resected BRAF-mutant melanoma. Furthermore, outcomes for melanoma with NRAS and KIT mutation receiving adjuvant immunotherapy remain unclear.

METHODS

One hundred seventy-four stage III melanoma patients who underwent radical surgery in Fudan University Shanghai Cancer Center (FUSCC) during January 2017 to December 2021 were included in this real-world study. Patients were followed up until death or May 30th, 2022. Pearson's chi-squared test or Fisher's exact test was performed for univariable analysis of the different category groups. Log-rank analysis was used to identify the prognostic factors for disease-free survival (DFS).

RESULTS

There were 41 (23.6%) patients with BRAF mutation, 31 (17.8%) with NRAS mutation, 17 (9.8%) with KIT mutation, and 85 (48.9%) wild-type patients without either genomic alteration of those three genes. Most ( n  = 118, 67.8%) of them were acral melanoma, while 45 (25.9%) were cutaneous subtype, and 11 were (6.3%) primary unknown. Among them, 115 (66.1%) patients received pembrolizumab or toripalimab monotherapy as adjuvant therapy; 22 (12.6%) patients received high-dose interferon (IFN), and 37 (21.3%) patients were just for observation. There was no statistical difference in clinicopathologic factors between anti-PD-1 group and IFN/OBS group. Of all the enrolled patients, anti-PD-1 group had a better DFS than IFN/OBS group ( p  = 0.039). In anti-PD-1 group, patients with BRAF or NRAS mutations had poorer DFS than wild-type group. No survival difference was found among patients harboring different gene mutations in IFN/OBS group. In wild-type patients, anti-PD-1 group had a better DFS than IFN/OBS group ( p  = 0.003), while no survival benefits were found for patients with BRAF, NRAS, or KIT mutations.

CONCLUSION

Although anti-PD-1 adjuvant therapy provides a better DFS in the general population and in wild-type patients, patients with BRAF, KIT or, especially, NRAS mutation may not benefit further from immunotherapy than conventional IFN treatment or observation.

Computational Model of Heterogeneity in Melanoma: Designing Therapies and Predicting Outcomes

Cutaneous melanoma is a highly invasive tumor and, despite the development of recent therapies, most patients with advanced metastatic melanoma have a poor clinical outcome. The most frequent mutations in melanoma affect the BRAF oncogene, a protein kinase of the MAPK signaling pathway. Therapies targeting both BRAF and MEK are effective for only 50% of patients and, almost systematically, generate drug resistance. Genetic and non-genetic mechanisms associated with the strong heterogeneity and plasticity of melanoma cells have been suggested to favor drug resistance but are still poorly understood. Recently, we have introduced a novel mathematical formalism allowing the representation of the relation between tumor heterogeneity and drug resistance and proposed several models for the development of resistance of melanoma treated with BRAF/MEK inhibitors. In this paper, we further investigate this relationship by using a new computational model that copes with multiple cell states identified by single cell mRNA sequencing data in melanoma treated with BRAF/MEK inhibitors. We use this model to predict the outcome of different therapeutic strategies. The reference therapy, referred to as “continuous” consists in applying one or several drugs without disruption. In “combination therapy”, several drugs are used sequentially. In “adaptive therapy” drug application is interrupted when the tumor size is below a lower threshold and resumed when the size goes over an upper threshold. We show that, counter-intuitively, the optimal protocol in combination therapy of BRAF/MEK inhibitors with a hypothetical drug targeting cell states that develop later during the tumor response to kinase inhibitors, is to treat first with this hypothetical drug. Also, even though there is little difference in the timing of emergence of the resistance between continuous and adaptive therapies, the spatial distribution of the different melanoma subpopulations is more zonated in the case of adaptive therapy.

Risk of Immune-Related Pneumonitis with PD-1/PD-L1 Inhibitors in Different Cancer Types and Treatment Regimens: A Systematic Review and Meta-Analysis of 22 Randomized Controlled Trials

BACKGROUND

Pneumonitis, the specific toxicity associated with PD-1/PD-L1 inhibitors, is severe and potentially life-threatening, and its incidence and severity are poorly understood among different tumor types or treatment methods. This meta-analysis was performed to compare the incidence and severity of pneumonitis among different tumor types and treatment regimens.

METHODS

MEDLINE and Embase were retrieved until September 2021. Meta-analysis of the risk of pneumonitis was calculated using a fixed-effect model. Pooled analysis of the incidence of pneumonitis in different tumor types was performed using a metaprop function.

RESULTS

Twenty two randomized controlled trials (RCTs) (n = 10,700) were included for pool analysis, and eighteen RCTs (n = 8,852) were eligible for meta-analysis. For all-grade pneumonitis, the risk of the combination therapy (PD-1/PD-L1 plus CTLA-4 inhibitor) was 3.62 times significantly higher than that of monotherapy, and 4.06 and 1.78 times significantly higher than that of chemotherapy and placebo than monotherapy. The incidence of pneumonitis was not significantly different between PD-1/PD-L1 inhibitor versus ipilimumab or between low doses versus high doses. For high-grade (grade ≥3) pneumonitis, the risk in PD-1/PD-L1 inhibitors alone was 3.62 times significantly higher than chemotherapy. No significant difference was found in the incidence of pneumonitis between combination versus monotherapy, monotherapy versus placebo, combination versus ipilimumab alone, monotherapy versus ipilimumab alone, or low doses versus high doses.

CONCLUSIONS

Compared with chemotherapy, PD-1/PD-L1 inhibitor monotherapy may cause more treatment-related pneumonitis. Increasing the dose of PD-1/PD-L1 inhibitor does not significantly increase the incidence of pneumonitis. Compared with the monotherapy, combination therapy does not increase the incidence of pneumonitis significantly.