The role of checkpoint inhibitors immunotherapy in advanced non-small cell lung cancer in the elderly

Circulating Osteopontin Predicts Clinical and Radiological Response in First-Line Treatment of Advanced Non-Small Cell Lung Cancer

PURPOSE

Pembrolizumab-based regimens are conditioned by the expression of PD-L1, but durable response rate is limited by innate and acquired resistance mechanisms. Here, we focus on osteopontin (OPN), an upfront biomarker of senescence, which closely associated with natural history of non-small cell lung cancer (NSCLC).

METHODS

Seventy-nine patients eligible to pembrolizumab regimens-alone or in combination with chemotherapy-as first-line treatment of advanced NSCLC were enrolled. Predictive value of OPN toward iRECIST progression disease (PD) was set as first outcome. Secondary ones included performance status (ECOG) at baseline, early (first and best) responses, and overall survival (OS).

RESULTS

High Serum OPN characterized patients with worse ECOG-PS (p = 0.015) at baseline and subjects experienced PD/death at first (OR 1.17 [1.02 to 1.35]; p = 0.030) and best responses (0.04 [0.00 to 0.81]; p = 0.035). OPN was associated with time-to-progression (B -2.74 [-4.46 to -1.01]) and time-to death (-0.13 [-0.20 to -0.05]). Cox regression models unveil a predictive value for iRECIST-PD (HR 1.01 [1.00 to 1.02]; p = -0.005), RECIST-PD (HR 1.01 [1.00 to 1.02]; p = 0.017), and OS (HR 1.02 [1.01 to 1.03]; p = 0.001). These models were internally validated through bootstrap resampling and characterized by relevant discrimination ability at ROC curve analyses.

CONCLUSION

Baseline levels of serum OPN is closely associated with performance status and short/long term outcomes in patients with advanced NSCLC, which are candidate to pembrolizumab-based regimens. As upfront biomarker of senescence, OPN may pave the way for future studies focusing on senescence patterns in NSCLC.

The prevalence of end-of-life chemotherapy and targeted therapy in Japan, assessed using a health claims database

PURPOSE

This study aimed to investigate the current status of end-of-life chemotherapy and targeted therapy and explore the aggressiveness of end-of-life care in Japan using the DeSC database, a large administrative claims database.

METHODS

We identified fatal cases of at least one cancer-related diagnosis between April 2015 and November 2020. Patients prescribed at least one anticancer drug were analyzed, and chemotherapy regimens were categorized based on the combination of concomitant anticancer drugs prescribed.

RESULTS

Among 1,095,713 individuals enrolled in the National Health Insurance database, 7,300 deaths with cancer-related diagnosis were identified. Of these, 4,010 cases were identified in which at least one anticancer drug was prescribed, and 11.6% of 7,300 death had been prescribed anticancer drugs in their last 30 days of life. The most commonly used regimen was S-1 (tegafur, gimeracil, and oteracil potassium combination) monotherapy, followed by nivolumab monotherapy and nab-paclitaxel plus gemcitabine. Immune checkpoint inhibitor monotherapy was more likely prescribed to patients whose last chemotherapy dose was in the last 30 days of life (p = 0.0066, chi-squared test).

CONCLUSIONS

This study provides insights into the current status of end-of-life chemotherapy and targeted therapy in Japan, using a large administrative claims database. The results of this study will inform future research on end-of-life chemotherapy and targeted therapy, and help develop strategies to improve the quality of life of patients with advanced cancer.

Docosahexaenoic acid reverses PD-L1-mediated immune suppression by accelerating its ubiquitin-proteasome degradation

PD-L1 interacts with its receptor PD-1 on T cells to negatively regulate T cell function, leading to cancer cell immune escape from the immune surveillance. Therefore, targeting PD-L1 is considered to be an attractive approach for cancer immunotherapy. In this study, we demonstrated for the first time that ω-3 polyunsaturated fatty acid (PUFA) docosahexaenoic acid (DHA) reduced the expression of PD-L1 in cancer cells both in vitro and in vivo. Promotion of PD-L1 ubiquitin-proteasome degradation by DHA resulted in a decrease of PD-L1 expression, leading to reduction of PD-L1 and PD-1 interaction, and reversing PD-L1-mediated immune suppression, which in turn contributed to the inhibitory effect on tumor growth. Furtherly, DHA significantly reduced fatty acid synthase (FASN) expression in cancer cells, which inhibited the palmitoyltransferases DHHC5, promoting the CSN5-dependent PD-L1 degradation. Our present finding uncovered a novel mechanism involved in the anti-cancer activity of DHA, and implicated that DHA holds promising potential to be developed as a novel immune-enhancer for cancer treatment and prevention.

Disparities in Representation of Women, Older Adults, and Racial/Ethnic Minorities in Immune Checkpoint Inhibitor Trials

PURPOSE

We aim to describe reporting and representation of minority patient populations in immune checkpoint inhibitor (ICI) clinical trials and assess predictors of enrollment disparity.

METHODS

Trial-level data were acquired from eligible phase II and III trials. Population-based estimates were acquired from the SEER 18 and Global Burden of Disease incidence databases. Trials reporting race, age, and sex were summarized using descriptive statistics. Enrollment-incidence ratio (EIR) was used to assess representation of subgroups. Average annual percentage change (AAPC) in EIR was calculated using Joinpoint Regression Analysis. Trial-level characteristics associated with EIR were assessed using multivariable linear regression.

RESULTS

A total of 107 trials with 48,095 patients were identified. Participation of Black, White, Asian, Native American, Pacific Islander, and Hispanic participants was reported in 65 (61%), 77 (72%), 68 (64%), 40 (37%,) and 24 trials (22%), respectively. Subgroup analyses of clinical outcomes by race, age, and sex were reported in 17 (22%), 62 (78%), and 57 (57%) trials, respectively. Women (trial proportion [TP]: 32%; EIR: 0.90 [95% confidence interval [CI]: 0.84-0.96]), patients aged ≥65 years (TP: 42%; EIR: 0.78 [95% CI: 0.72-0.84]), Black participants (TP: 1.9%; EIR: 0.17 [95% CI: 0.13-0.22]) and Hispanics (TP: 5.9%; EIR: 0.67 [95% CI: 0.53-0.82]) were underrepresented. Representation of Black patients decreased significantly from 2009 to 2020 (AAPC: -23.13). Black participants were significantly underrepresented in phase III trials (P < .001).

CONCLUSION

The reporting of participation by racial or ethnic subgroup categories is inadequate. Women, older adults, as well as Black and Hispanic participants are significantly underrepresented in ICI clinical trials.

Platinum-Based Chemotherapy in Older Patients with Non-Small Cell Lung Cancer: What to Expect in the Real World

BACKGROUND

The role of platinum-based chemotherapy (PBC) for the treatment of older patients with non-small cell lung cancer (NSCLC) is still a matter of debate, despite the advent of immunotherapy.

OBJECTIVE

The aim of the study was to identify factors associated with first-line PBC prescription and, secondly, to evaluate the impact of first-line PBC on survival, treatment intensity, risk of hospitalization, and subsequent treatments.

PATIENTS AND METHODS

We reviewed a consecutive series of 474 older patients (age ≥ 70 years) diagnosed with stage IIIB-IV NSCLC at the Department of Oncology, University Hospital of Udine, Italy from January 2009 to March 2017.

RESULTS

Overall, 198 patients were deemed eligible, and 65.2% received a PBC. At multivariate analysis, older age was the only factor associated with PBC prescription. In the whole cohort, 46 patients (23.2%) were hospitalized for chemotherapy-related toxicity. Both PBC prescription (odds ratio [OR] 2.23, 95% confidence interval [CI] 1.02-4.87, p = 0.04) and tumor burden (OR 2.39, 95% CI 1.07-5.32, p = 0.03) emerged as independent risk factors for hospitalization. Moving to significant predictors of patterns of care, Eastern Cooperative Oncology Group (ECOG) performance status > 0 was associated with greater risk of first-line failure (OR 2.20, 95% CI 1.15-4.20, p = 0.02), while bone metastases (OR 0.29, 95% CI 0.12-0.69, p = 0.005) and a Charlson Comorbidity Index score ≥ 3 (OR 0.40, 95% CI 0.19-0.84, p = 0.016) independently predicted lower probability of receiving second-line therapy. Remarkably, PBC did not significantly impact overall survival (hazard ratio [HR] 0.83, 95% CI 0.61-1.14, p = 0.24) and progression-free survival (HR 0.95, 95% CI 0.70-1.28, p = 0.73) compared to single-agent chemotherapy (SAC). However, according to an exploratory landmark analysis, patients who received four cycles of treatment or maintenance therapy experienced prolonged overall survival, regardless of PBC use.

CONCLUSIONS

This study evaluated the real-world use of PBC in older patients with NSCLC, offering an insight into the determinants of its prescription and the pattern of care of these patients. Of note, PBC use was associated with a higher likelihood of hospitalization for chemotherapy-related toxicity, with no benefit on survival compared to SAC.

LOXL1-AS1 Contributes to Non-Small Cell Lung Cancer Progression by Regulating miR-3128/RHOXF2 Axis

Purpose

The purpose of this study was to investigate the molecular mechanism of LncRNA LOXL1-AS1 in non-small cell lung cancer (NSCLC).

Methods

Lung cancer cell lines (H1299, A549, H520 and H596) and human normal lung epithelial cell line (BEAS-2B) were used in this study. Gene expression was measured by qRT-PCR (quantitative real-time PCR). The bioinformatics databases (miRDB and TargetScan7) were used to predict target genes. Luciferase assay and pull-down assay were processed for verifying the binding sites. CCK8 assay was used for detecting proliferation, and transwell assay was undertaken for migration and invasion.

Results

LncRNA LOXL1-AS1 was higher expressed in lung cancer tissues and cells. Moreover, LOXL1-AS1 expression was upregulated in tumor tissues with advanced stages and metastasis. After knocking down LOXL1-AS1, proliferation, invasion and migration of H1299 and A549 cells were inhibited. Interestingly, miR-3128 was negatively regulated by LncRNA LOXL1-AS1, which inhibited the expression of RHOXF2. Rescue assay also confirmed that miR-3128 inhibitor and oeRHOXF2 could rescue the effect of down-regulated LOXL1-AS1 on proliferation, invasion and migration progression.

Conclusion

LOXL1-AS1 promotes the progression of NSCLC by regulating miR-3128/RHOXF2 axis, which might be a new potential target for the diagnosis and treatment of NSCLC.

Does progress achieved in the treatment of patients with metastatic non-small-cell lung cancer reach the elderly population? A cohort study from a cancer centre from Eastern Switzerland

OBJECTIVE

Treatment options for non-small-cell lung cancer (NSCLC) have been evolving. The goal of our study was to evaluate whether novel therapeutics are used in the elderly population and improve outcomes to a similar extent as in young patients.

METHODS

We enrolled patients registered in the Cancer Registry of Eastern Switzerland and grouped them into four cohorts: Elderly patients aged ≥70 years diagnosed 2005-2007 and 2015-2016 (elderly cohorts 1,2) were compared to cohorts of patients < 70 years diagnosed during the same time periods (young cohorts 1,2).

RESULTS

499 individuals were analysed. Median cancer-specific survival in the elderly cohorts 1 and 2 was 3.9 months and 6.3 months, respectively, and 8.0 and 12.7 months in the young cohorts 1 and 2. 12-month survival significantly improved over ten years only in younger patients (35.6% and 54.9%), however not in the elderly cohorts (20% vs. 35%). Proportion of patients receiving any line of systemic treatment remained lower in the elderly cohorts (53% vs. 78%).

CONCLUSION

Despite the increase in median cancer-specific survival in both cohorts, a significant and clinically meaningful improvement of 12-month cancer-specific survival was only seen in young patients. The adoption of novel treatment approaches is lagging behind in the elderly population.

Immune Checkpoint Blockade for Advanced NSCLC: A New Landscape for Elderly Patients

The therapeutic scenario for elderly patients with advanced NSCLC has been limited to radiotherapy and chemotherapy. Recently, a novel therapeutic approach based on targeting the immune-checkpoints has showed noteworthy results in advanced NSCLC. PD1/PD-L1 pathway is co-opted by tumor cells through the expression of PD-L1 on the tumor cell surface and on cells within the microenvironment, leading to suppression of anti-tumor cytolytic T-cell activity by the tumor. The success of immune-checkpoints inhibitors in clinical trials led to rapid approval by the FDA and EMA. Currently, data regarding efficacy and safety of ICIs in older subjects is limited by the poor number of elderly recruited in clinical trials. Careful assessment and management of comorbidities is essential to achieve better outcomes and limit the immune related adverse events in elderly NSCLC patients.

The Regulatory Status Adopted by Lymph Node Dendritic Cells and T Cells During Healthy Aging Is Maintained During Cancer and May Contribute to Reduced Responses to Immunotherapy

Aging is associated with an increased incidence of cancer. One contributing factor could be modulation of immune cells responsible for anti-tumor responses, such as dendritic cells (DCs) and T cells. These immunological changes may also impact the efficacy of cancer immunotherapies in the elderly. The effects of healthy aging on DCs and T cells, and their impact on anti-mesothelioma immune responses, had not been reported. This study examined DCs and T cells in young (2–5 months; equivalent to 16–26 human years) and elderly (20–24 months; equivalent to 60–70 human years) healthy and mesothelioma-bearing C57BL/6J mice. During healthy aging, elderly lymph nodes adopted a regulatory profile, characterized by: (i) increased plasmacytoid DCs, (ii) increased expression of the adenosine-producing enzyme CD73 on CD11c⁺ cells, and (iii) increased expression of multiple regulatory markers (including CD73, the adenosine A2B receptor, CTLA-4, PD-1, ICOS, LAG-3, and IL-10) on CD8⁺ and CD4⁺ T cells, compared to lymph nodes from young mice. Although mesotheliomas grew faster in elderly mice, the increased regulatory status observed in healthy elderly lymph node DCs and T cells was not further exacerbated. However, elderly tumor-bearing mice demonstrated reduced MHC-I, MHC-II and CD80 on CD11c⁺ cells, and decreased IFN-γ by CD8⁺ and CD4⁺ T cells within tumors, compared to young counterparts, implying loss of function. An agonist CD40 antibody based immunotherapy was less efficient at promoting tumor regression in elderly mice, which may be due to: (i) failure of elderly CD8⁺ T cells to up-regulate perforin, and (ii) increased expression of multiple regulatory markers on CD11c⁺ cells and T cells in elderly tumor-draining lymph nodes (including CD73, PD-1, ICOS, LAG-3, and TGF-β). Our findings suggest that checkpoint blockade may improve responses to immunotherapy in elderly hosts with mesothelioma, and warrants further investigation.

Pembrolizumab for the first-line treatment of non-small cell lung cancer

INTRODUCTION

Platinum-based chemotherapy had long played a role as standard therapy for the first-line treatment of advanced or recurrent non-small cell lung cancer (NSCLC). However, immune checkpoint inhibitors such as pembrolizumab, a monoclonal antibody that prevents programmed death protein 1 (PD-1) receptor, have brought a paradigm shift in this field. Areas covered: In this article, we review the relevant literatures and ongoing trials on the first-line treatment of pembrolizumab. Especially, in two pivotal phase III trials, KEYNOTE-024 and -189, both pembrolizumab monotherapy and combined pembrolizumab plus chemotherapy significantly prolonged overall survival (OS) compared to the existing platinum-based chemotherapy. Currently, multiple trials with combination therapy of pembrolizumab and other agents have been conducted, and further evidences are expected to be created. Expert opinion: Immune checkpoint inhibitors that block the PD-1/PD-L1 pathway are essential drugs for advanced or recurrent NSCLC, among which pembrolizumab becomes one of the standards of care in the first-line of NSCLC. For further improvement in efficacy of pembrolizumab, it is necessary to clarify the identification of biomarkers exclusive to PD-L1 expression, predictive factors for patients who benefit most from the agent.

Chromogenic Multiplex Immunohistochemistry Reveals Modulation of the Immune Microenvironment Associated with Survival in Elderly Patients with Lung Adenocarcinoma

With underrepresentation of elderly patients with lung adenocarcinoma (LADC) in anti-PD-1/PD-L1 clinical trials, better understanding of the interplay of PD-L1 and tumor-associated immune cells (TAICs) could assist clinicians in stratifying these patients for immunotherapy. One hundred and one patients with LADCs, stratified by age, were included for analysis of PD-L1 expression and density of TAICs expressing CD4, CD8, and CD33, by using multiplex chromogenic immunohistochemistry (IHC) assays and automated digital quantification. The CD4⁺/CD8⁺ ratio was significantly higher in elderly patients. In patients <75 years, the density of CD4⁺, CD8⁺, and PD-L1 in TAICs showed a positive significant correlation with PD-L1 expression in tumor cells (TCs), while a lower correlation was observed in the elderly population. In the latter, a high CD4⁺/CD8⁺ ratio, and combined PD-L1 expression ≥1% TCs with a low CD8⁺ density, low CD33⁺ density, and a high CD4⁺ density correlated to worse overall survival. We identified differences according to age in the CD4⁺/CD8⁺ ratio and in correlation between PD-L1 expression and the density of TAICs in LADC patients. Distinct groups of tumor microenvironments had an impact on the OS of elderly patients with LADC.

Immune-related adverse events and atypical radiological response with checkpoint inhibitor immunotherapy in an elderly patient with high PD-L1 expressing lung adenocarcinoma

Advances in immunotherapy have changed the therapeutic landscape of non-small cell lung cancer (NSCLC), extending overall survival over standard chemotherapy. However, by removing the protection against autoimmunity, immunotherapy can increase immune-related adverse events (irAEs). In addition, new patterns of radiological response have been observed in patients treated with immune checkpoint inhibitors (ICIs). We report the case of a 77 year-old patient with advanced lung adenocarcinoma, who presented three consecutive different irAEs (nephritis, hepatitis, and pneumonitis) and an atypical radiological response (partial response, dissociated response, and “disease flare”) in relation to treatment with the PD-1 inhibitor nivolumab. The role of ICIs in elderly patients, the incidence of consecutive irAEs, and the new patterns of radiological response, are also reviewed.

Use of nivolumab in elderly patients with advanced squamous non-small-cell lung cancer: results from the Italian cohort of an expanded access programme

AIM

This analysis evaluated the efficacy and safety of nivolumab, an immune checkpoint inhibitor, in elderly patients with stage IIIB or IV squamous non-small-cell lung cancer (NSCLC) enrolled in the expanded access programme (EAP) in Italy.

METHODS

Nivolumab was available on physician request. Safety data included adverse events (AEs). Efficacy data included investigator-assessed tumour response, progression date and survival information. Results were analysed for patients aged <65, 65-<75 and ≥75 years and for the overall population.

RESULTS

A total of 371 patients with squamous NSCLC were enrolled at 96 centres between April 2015 and September 2015; 34% (n = 126), 47% (n = 175) and 19% (n = 70) were aged <65, 65-<75 and ≥75 years, respectively. Efficacy was similar among patients aged <65, 65-<75 and ≥75 years and the overall population (objective response rates: 18%, 18%, 19% and 18%, respectively; disease control rates: 49%, 47%, 43% and 47%, respectively). Median overall survival was reduced in patients aged ≥75 years (5.8 months) versus patients aged <65; years (8.6 months), patients aged 65-<75 years (8.0 months) and the overall population (7.9 months). The incidence of grade 3-4 treatment-related AEs was low in patients aged 65, 65-<75 and ≥75 years and the overall population (3%, 9%, 3%, 6%, respectively). Discontinuation rates due to treatment-related AEs were low irrespective of age (4-5%).

CONCLUSIONS

These EAP results suggest that elderly patients with advanced squamous NSCLC benefit from nivolumab, with tolerability similar to that in the overall population.

Clinical factors associated with early progression and grade 3-4 toxicity in patients with advanced non-small-cell lung cancers treated with nivolumab

Introduction

The prognosis of advanced non-small-cell lung cancer (NSCLC) has been improved by development of immune checkpoint inhibitors (ICIs) such as nivolumab for second-line treatment. As phase III trials include only selected patients, we here investigated the clinical factors associated with efficacy and safety of nivolumab in ‘real life’ patients with advanced NSCLC.

Methods

Clinical and histological characteristics, therapies and survival data of all consecutive patients with advanced NSCLC included prospectively and treated by nivolumab in two French academic hospitals between February 2015 and December 2016 were examined.

Results

Sixty-seven patients were included, mostly male (69%), current or former smokers (87%) with PS <2 (73%). Median age was 68.5 years and 42% were aged ≥70 years. According to uni- and multi-variate analyses, only PS 2 (OR = 0.17, 95% CI 0.03–0.99, p = 0.049) and number of previous treatment lines (OR = 0.33, 95% CI 0.13–0.85, p = 0.022) were significantly negatively associated with tumor control. Worse progression-free survival (PFS) was significantly associated with PS 2 (HR = 5.17, 95% CI 1.99–13.43, p = 0.001) and use of steroids (HR = 3.27, 95% CI 1.39–7.69, p = 0.006). Worse overall survival was associated with symptomatic brain metastasis (HR = 3.15, 95% CI 1.23–8.85, p = 0.029). Treatment-related adverse events occurred in 47 patients (70%), symptomatic brain metastasis being significantly associated with Grade ≥3 toxicity (OR = 8.13, 95% CI 1.21–55.56, p = 0.031). Age and nutritional status were not associated with response, PFS, OS or toxicity.

Conclusion

Our results suggest that nivolumab is not beneficial or safe for patients with PS 2 and symptomatic brain metastases.

Overcoming Barriers of Age to Enhance Efficacy of Cancer Immunotherapy: The Clout of the Extracellular Matrix

There is a growing list of cancer immunotherapeutics approved for use in a population with an increasing number of aged individuals. Cancer immunotherapy (CIT) mediates tumor destruction by activating anti-tumor immune responses that have been silenced through the oncogenic process. However, in an aging individual, immune deregulation is positively correlated with age. In this context, it is vital to examine the age-related changes in the tumor microenvironment (TME) and specifically, those directly affecting critical players to ensure CIT efficacy. Effector T cells, regulatory T cells, myeloid-derived suppressor cells, tumor-associated macrophages, and tumor-associated neutrophils play important roles in promoting or inhibiting the inflammatory response, while cancer-associated fibroblasts are key mediators of the extracellular matrix (ECM). Immune checkpoint inhibitors function optimally in inflamed tumors heavily invaded by CD4 and CD8 T cells. However, immunosenescence curtails the effector T cell response within the TME and causes ECM deregulation, creating a biophysical barrier impeding both effective drug delivery and pro-inflammatory responses. The ability of the chimeric antigen receptor T (CAR-T) cell to artificially induce an adaptive immune response can be modified to degrade essential components of the ECM and alleviate the age-related changes to the TME. This review will focus on the age-related alterations in ECM and immune-stroma interactions within the TME. We will discuss strategies to overcome the barriers of immunosenescence and matrix deregulation to ameliorate the efficacy of CIT in aged subjects.

Stress-induced cellular responses in immunogenic cell death: Implications for cancer immunotherapy

Cancer is evading the host's defense mechanisms leading to avoidance of immune destruction. During tumor progression, immune-evading cancer cells arise due to selective pressure from the hypoxic and nutrient-deprived microenvironment. Thus, therapies aiming at re-establishing immune destruction of pathological cells constitute innovating anti-cancer strategies. Accumulating evidence suggests that selected conventional chemotherapeutic drugs increase the immunogenicity of stressed and dying cancer cells by triggering a form of cell death called immunogenic cell death (ICD), which is characterized by the release of danger-associated molecular patterns (DAMPs). In this review, we summarize the effects of ICD inducers on DAMP signaling leading to adjuvanticity and antigenicity. We will discuss the associated stress response pathways that cause the release of DAMPs leading to improved immune recognition and their relevance in cancer immunotherapy. Our aim is to highlight the contribution of adaptive immunity to the long-term clinical benefits of anticancer treatments and the properties of immune memory that can protect cancer patients against relapse.

Osimertinib (AZD9291) decreases programmed death ligand-1 in EGFR-mutated non-small cell lung cancer cells

Osimertinib (AZD9291) is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) that has been approved for the treatment of EGFR-mutated non-small cell lung cancer (NSCLC). In NSCLC patients, an EGFR mutation is likely to be correlated with high levels of expression of programmed death ligand-1 (PD-L1). Here, we showed that osimertinib decreased PD-L1 expression in human EGFR mutant NSCLC cells in vitro. Osimertinib (125 nmol/L) markedly suppressed PD-L1 mRNA expression in both NCI-H1975 and HCC827 cells. Pretreatment with the N-linked glycosylation inhibitor tunicamycin, osimertinib clearly decreased the production of new PD-L1 protein probably due to a reduction in mRNA. After blocking transcription and translation processes with actinomycin D and cycloheximide, respectively, osimertinib continued to reduce the expression of PD-L1, demonstrating that osimertinib might degrade PD-L1 at the post-translational level, which was confirmed by a cycloheximide chase assay, revealing that osimertinib (125 nmol/L) decreased the half-life of PD-L1 from approximately 17.8 h and 13.8 h to 8.6 h and 4.6 h, respectively, in NCI-H1975 and HCC827 cells. Pretreatment with the proteasome inhibitors (MG-132 or bortezomib) blocked the osimertinib-induced degradation of PD-L1, but an inhibitor of autophagy (chloroquine) did not. In addition, inhibition of GSK3β by LiCl prevented osimertinib-induced PD-L1 degradation. The results demonstrate that osimertinib reduces PD-L1 mRNA expression and induces its protein degradation, suggesting that osimertinib may reactivate the immune activity of T cells in the tumor microenvironment in EGFR-mutated NSCLC patients.

Modulation of dendritic cell and T cell cross-talk during aging: The potential role of checkpoint inhibitory molecules

Dendritic cells (DCs) undergo continuous changes throughout life, and there is evidence that elderly DCs have a reduced capacity to stimulate T cells, which may contribute to impaired anti-tumour immune responses in elderly people with cancer. Changes in checkpoint inhibitory molecules/pathways during aging may be one mechanism that impairs the ability of elderly DCs to activate T cells. However, little is currently known regarding the combined effects of aging and cancer on DC and T cell inhibitory molecules/pathways. In this review, we discuss our current understanding of the influence of aging and cancer on key DC and T cell inhibitory molecules/pathways, the potential underlying cellular and molecular mechanisms contributing to their modulation, and the possibility of therapeutically targeting inhibitory molecules in elderly cancer patients.