Pemetrexed Enhances Membrane PD-L1 Expression and Potentiates T Cell-Mediated Cytotoxicity by Anti-PD-L1 Antibody Therapy in Non-Small-Cell Lung Cancer

Centipeda minima and 6-O-angeloylplenolin enhance the efficacy of immune checkpoint inhibitors in non-small cell lung cancer

BACKGROUND

Chemotherapeutic agents including cisplatin, gemcitabine, and pemetrexed, significantly enhance the efficacy of immune checkpoint inhibitors (ICIs) in non-small cell lung cancer (NSCLC) by increasing PD-L1 expression and potentiating T cell cytotoxicity. However, the low response rate and adverse effects limit the application of chemotherapy/ICI combinations in patients.

METHODS

We screened for medicinal herbs that could perturb PD-L1 expression and enhance T cell cytotoxicity in the presence of anti-PD-L1 antibody, and investigated the underlying mechanisms.

RESULTS

We found that the aqueous extracts of Centipeda minima (CM) significantly enhanced the cancer cell-killing activity and granzyme B expression level of CD8+ T cells, in the presence of anti-PD-L1 antibody. Both CM and its active component 6-O-angeloylplenolin (6-OAP) upregulated PD-L1 expression by suppressing GSK-3β-β-TRCP-mediated ubiquitination and degradation. CM and 6-OAP significantly enhanced ICI-induced reduction of tumor burden and prolongation of overall survival of mice bearing NSCLC cells, accompanied by upregulation of PD-L1 and increase of CD8+ T cell infiltration. CM also exhibited anti-NSCLC activity in cells and in a patient-derived xenograft mouse model.

CONCLUSIONS

These data demonstrated that the induced expression of PD-L1 and enhancement of CD8+ T cell cytotoxicity underlay the beneficial effects of 6-OAP-rich CM in NSCLCs, providing a clinically available and safe medicinal herb for combined use with ICIs to treat this deadly disease.

Immunomodulatory effects of antiangiogenic tyrosine kinase inhibitors in renal cell carcinoma models: Impact on following anti-PD-1 treatments

The approval of immune checkpoint inhibitors (ICIs) has revolutionized the management of metastatic renal cell carcinoma (RCC), introducing several ICI-based combinations as the new standard of care for affected patients. Nonetheless, monotherapy with antiangiogenic tyrosine kinase inhibitors (TKIs), such as pazopanib or sunitinib, still represents a first-line treatment option for selected patients belonging to the favorable risk group according to the International mRCC Database Consortium (IMDC) model. After TKI monotherapy, the main second-line option is represented by ICI monotherapy with the anti-Programmed Death Receptor 1(PD-1) nivolumab. To date, the expected clinical outcomes are similar with pazopanib or sunitinib and there is no clear indication for selecting one TKI over the other. Moreover, their impact on subsequent ICI treatment outcomes is not well defined, yet. Based on these premises, we investigated the immunomodulatory activity of these drugs in vitro and in vivo.Both TKIs induced Programmed Cell Death Ligand-1 (PD-L1) expression and soluble PD-L1 release in RCC cells, and hampered T cell activation, reducing cytokine production and the proportion of activated T cells. Nevertheless, in a syngeneic co-culture system with peripheral blood mononuclear cells (PBMCs) and tumor cells, incubation with anti-PD-1 antibody following TKIs treatment significantly restored T cell function, potentiating the cytotoxic effects against tumor cells. Pazopanib and sunitinib followed by anti-PD-1 antibody produced a comparable inhibition of tumor growth in a RCC syngeneic mouse model. Our findings suggest that pazopanib and sunitinib, showing similar immunomodulatory effects, may have a comparable impact on the subsequent effectiveness of PD-1/PD-L1 blockade.

The significance of inflammatory markers in prognosticating the effectiveness and safety of immunotherapy in conjunction with chemotherapy during the primary intervention of advanced non-small cell lung carcinoma

OBJECTIVE

The aim of this study is to scrutinize the prognostic significance of inflammatory biomarkers concerning the effectiveness and safety of combining PD-1 inhibition with chemotherapy in the management of advanced NSCLC.

METHODS

We conducted a retrospective analysis involving 206 NSCLC patients who received treatment at Qingdao Municipal Hospital. The study encompassed the acquisition of baseline clinical attributes and hematological parameters of these patients. The optimal threshold values for PLT and NLR were ascertained based on pre-treatment evaluations, with a particular focus on their association with PFS. Variables linked to PFS were subject to scrutiny through Kaplan-Meier analysis and logistic regression. The Receiver Operating Characteristic (ROC) curve served as the means to determine the ideal cut-off values for categorizing levels of inflammatory markers into high and low classifications. We employed Chi-square tests to evaluate the relationship between elevated and reduced baseline levels of inflammatory markers and irAE.

RESULTS

Kaplan-Meier analysis disclosed that patients in the low baseline PLT group and the low NLR group exhibited a substantially more favorable prognosis in contrast to their counterparts in the high baseline PLT and high NLR groups. Multivariate analysis indicated that diminished baseline PLT and NLR levels before treatment independently foretell extended PFS. Chi-square analysis underscored a substantial correlation between baseline WBC, NEUT, LYMPH, MONO, and NLR levels and irAE.

CONCLUSION

Subdued baseline PLT and NLR levels may serve as indicators of a more auspicious prognosis in patients contending with advanced NSCLC undergoing the combination of PD-1 inhibition and chemotherapy. Elevated baseline levels of inflammatory markers antedating PD-1 therapy in advanced NSCLC may be intimately interrelated with the occurrence of irAE.

Enhancing Effector Jurkat Cell Activity and Increasing Cytotoxicity against A549 Cells Using Nivolumab as an Anti-PD-1 Agent Loaded on Gelatin Nanoparticles

The current research investigated the use of gelatin nanoparticles (GNPs) for enhancing the cytotoxic effects of nivolumab, an immune checkpoint inhibitor. The unique feature of GNPs is their biocompatibility and functionalization potential, improving the delivery and the efficacy of immunotherapeutic drugs with fewer side effects compared to traditional treatments. This exploration of GNPs represents an innovative direction in the advancement of nanomedicine in oncology. Nivolumab-loaded GNPs were prepared and characterized. The optimum formulation had a particle size of 191.9 ± 0.67 nm, a polydispersity index of 0.027 ± 0.02, and drug entrapment of 54.67 ± 3.51%. A co-culture experiment involving A549 target cells and effector Jurkat cells treated with free nivolumab solution, and nivolumab-loaded GNPs, demonstrated that the latter had significant improvements in inhibition rate by scoring 87.88 ± 2.47% for drug-loaded GNPs against 60.53 ± 3.96% for the free nivolumab solution. The nivolumab-loaded GNPs had a lower IC50 value, of 0.41 ± 0.01 µM, compared to free nivolumab solution (1.22 ± 0.37 µM) at 72 h. The results indicate that administering nivolumab-loaded GNPs augmented the cytotoxicity against A549 cells by enhancing effector Jurkat cell activity compared to nivolumab solution treatment.

Inhalable metal-organic framework-mediated cuproptosis combined with PD-L1 checkpoint blockade for lung metastasis synergistic immunotherapy

Cuproptosis shows enormous application prospects in lung metastasis treatment. However, the glycolysis, Cu+ efflux mechanisms, and insufficient lung drug accumulation severely restrict cuproptosis efficacy. Herein, an inhalable poly (2-(N-oxide-N,N-diethylamino)ethyl methacrylate) (OPDEA)-coated copper-based metal-organic framework encapsulating pyruvate dehydrogenase kinase 1 siRNA (siPDK) is constructed for mediating cuproptosis and subsequently promoting lung metastasis immunotherapy, namely OMP. After inhalation, OMP shows highly efficient lung accumulation and long-term retention, ascribing to the OPDEA-mediated pulmonary mucosa penetration. Within tumor cells, OMP is degraded to release Cu2+ under acidic condition, which will be reduced to toxic Cu+ to induce cuproptosis under glutathione (GSH) regulation. Meanwhile, siPDK released from OMP inhibits intracellular glycolysis and adenosine-5'-triphosphate (ATP) production, then blocking the Cu+ efflux protein ATP7B, thereby rendering tumor cells more sensitive to OMP-mediated cuproptosis. Moreover, OMP-mediated cuproptosis triggers immunogenic cell death (ICD) to promote dendritic cells (DCs) maturation and CD8+ T cells infiltration. Notably, OMP-induced cuproptosis up-regulates membrane-associated programmed cell death-ligand 1 (PD-L1) expression and induces soluble PD-L1 secretion, and thus synergizes with anti-PD-L1 antibodies (aPD-L1) to reprogram immunosuppressive tumor microenvironment, finally yielding improved immunotherapy efficacy. Overall, OMP may serve as an efficient inhalable nanoplatform and afford preferable efficacy against lung metastasis through inducing cuproptosis and combining with aPD-L1.

PD-L1 overexpression induces STAT signaling and promotes the secretion of pro-angiogenic cytokines in non-small cell lung cancer (NSCLC)

BACKGROUND

Monoclonal antibodies (ICI) targeting the immune checkpoint PD-1/PD-L1 alone or in combination with chemotherapy have demonstrated relevant benefits and established new standards of care in first-line treatment for advanced non-oncogene addicted non-small cell lung cancer (NSCLC). However, a relevant percentage of NSCLC patients, even with high PD-L1 expression, did not respond to ICI, highlighting the presence of intracellular resistance mechanisms that could be dependent on high PD-L1 levels. The intracellular signaling induced by PD-L1 in tumor cells and their correlation with angiogenic signaling pathways are not yet fully elucidated.

METHODS

The intrinsic role of PD-L1 was initially checked in two PD-L1 overexpressing NSCLC cells by transcriptome profile and kinase array. The correlation of PD-L1 with VEGF, PECAM-1, and angiogenesis was evaluated in a cohort of advanced NSCLC patients. The secreted cytokines involved in tumor angiogenesis were assessed by Luminex assay and their effect on Huvec migration by a non-contact co-culture system.

RESULTS

PD-L1 overexpressing cells modulated pathways involved in tumor inflammation and JAK-STAT signaling. In NSCLC patients, PD-L1 expression was correlated with high tumor intra-vasculature. When challenged with PBMC, PD-L1 overexpressing cells produced higher levels of pro-angiogenic factors compared to parental cells, as a consequence of STAT signaling activation. This increased production of cytokines involved in tumor angiogenesis largely stimulated Huvec migration. Finally, the addition of the anti-antiangiogenic agent nintedanib significantly reduced the spread of Huvec cells when exposed to high levels of pro-angiogenic factors.

CONCLUSIONS

In this study, we reported that high PD-L1 modulates STAT signaling in the presence of PBMC and induces pro-angiogenic factor secretion. This could enforce the role of PD-L1 as a crucial regulator of the tumor microenvironment stimulating tumor progression, both as an inhibitor of T-cell activity and as a promoter of tumor angiogenesis.

Durvalumab and taxane family combination therapy enhances the antitumoral effects for NSCLC: An in vitro study

Immunotherapy has lately become the most preferred cancer treatment method, and for non-small cell lung cancer (NSCLC) first-line treatment, there are many immunotherapy options. This study aimed to assess the effectiveness and toxicity of paclitaxel (PTX), docetaxel (DTX) chemotherapy, immune checkpoint inhibitor treatment (durvalumab; DVL), and their combination in NSCLC. A-549 cells were treated with DVL in combination with PTX and DTX (a quarter of the IC50 ) to investigate their anticancer effects on these cells. The MTT assay, wound healing tests, and double-staining with Annexin V/PI were used to assess the cell viability, apoptosis, and migration. The results showed that a combination of 0.35 mg/mL DVL with 6.5 μg/mL PTX and 1.75 μg/mL DTX produced a synergistic effect with CI values of 0.88, 0.37, and 0.81, respectively. Moreover, the PTX + DTX + DVL combination led to a significantly increased apoptotic rate up to 88.70 ± 3.39% in the A549 cell line compared to monotherapy (p < .001). In addition, we found that the combination therapy with these agents increased the expression level of Bax, Cas-3, p53, and Bax/Bcl-2 ratio in all experimental groups. In conclusion, the results suggest that combining anti-PD-L1 antibody therapy with chemotherapy may provide a promising approach to enhance treatment outcomes and be a potentially efficacious strategy for treating NSCLC patients. Further research and clinical investigations are needed to elucidate the underlying molecular mechanisms and validate the therapeutic potential of these compounds in vivo.

A Photoactive Supramolecular Complex Targeting PD-L1 Reveals a Weak Correlation between Photoactivation Efficiency and Receptor Expression Levels in Non-Small-Cell Lung Cancer Tumor Models

Photo-immunotherapy uses antibodies conjugated to photosensitizers to produce nanostructured constructs endowed with targeting properties and photo-inactivation capabilities towards tumor cells. The superficial receptor density on cancer cells is considered a determining factor for the efficacy of the photodynamic treatment. In this work, we propose the use of a photoactive conjugate that consists of the clinical grade PD-L1-binding monoclonal antibody Atezolizumab, covalently linked to either the well-known photosensitizer eosin or the fluorescent probe Alexa647. Using single-molecule localization microscopy (direct stochastic optical reconstruction microscopy, dSTORM), and an anti-PD-L1 monoclonal antibody labelled with Alexa647, we quantified the density of PD-L1 receptors exposed on the cell surface in two human non-small-cell lung cancer lines (H322 and A549) expressing PD-L1 to a different level. We then investigated if this value correlates with the effectiveness of the photodynamic treatment. The photodynamic treatment of H322 and A549 with the photo-immunoconjugate demonstrated its potential for PDT treatments, but the efficacy did not correlate with the PD-L1 expression levels. Our results provide additional evidence that receptor density does not determine a priori the level of photo-induced cell death.

Exploring the Molecular Players behind the Potentiation of Chemotherapy Effects by Durvalumab in Lung Adenocarcinoma Cell Lines

Immune checkpoint inhibitors are increasingly used in combination with chemotherapy for the treatment of non-small cell lung cancer, yet the success of combination therapies is relatively limited. Thus, more detailed insight regarding the tumor molecular markers that may affect the responsiveness of patients to therapy is required. Here, we set out to explore the proteome of two lung adenocarcinoma cell lines (HCC-44 and A549) treated with cisplatin, pemetrexed, durvalumab, and the corresponding mixtures to establish the differences in post-treatment protein expression that can serve as markers of chemosensitivity or resistance. The mass spectrometry study showed that the addition of durvalumab to the treatment mixture resulted in cell line- and chemotherapeutic agent-dependent responses and confirmed the previously reported involvement of DNA repair machinery in the potentiation of the chemotherapy effect. Further validation using immunofluorescence also indicated that the potentiating effect of durvalumab in the case of cisplatin treatment was dependent on the tumor suppressor RB-1 in the PD-L1 weakly positive cells. In addition, we identified aldehyde dehydrogenase ALDH1A3 as the general putative resistance marker. Further studies in patient biopsy samples will be required to confirm the clinical significance of these findings.

Rational pemetrexed combined with CIK therapy plus anti-PD-1 mAbs administration sequence will effectively promote the efficacy of CIK therapy in non-small cell lung cancer

Cytokine-induced killer (CIK) cells are heterogeneous cells composed mainly of CD3⁺CD56⁺ T cells. As an important treatment method of adoptive therapy, it has shown promising efficacy in many clinical trials, especially in combination with multidrug therapy. However, the maximal antitumor efficacy of CIK therapy in the combined administration of multidrug and CIK therapies and which administration scheme can maximize the antitumor efficacy of CIK therapy are still remain unclear. In this study, we observed that pemetrexed administration prior to the injection of CIK cells maximizes the efficacy of CIK therapy. Anti-PD-1 mAbs should be administered prior to CIK cell injection to maximize the efficacy of the therapy. However, administering anti-PD-1 mAbs after CIK cell injection significantly affects the binding rate of anti-PD-1 mAbs to the PD-1 receptor on CIK cells, affecting the efficacy of the antitumor therapy. In conclusion, our study observed that a rational administration sequence of pemetrexed combined with CIK therapy and anti-PD-1 mAbs significantly promotes the efficacy of CIK therapy, providing an experimental basis for the combination therapy mode and regimen of CIK therapy in clinical practice. We hope that this study can provide patients with lung adenocarcinoma with a prolonged survival time.

Soluble PD-L1: a potential dynamic predictive biomarker for immunotherapy in patients with proficient mismatch repair colorectal cancer

BACKGROUND

Circulating soluble programmed death ligand 1 (sPD-L1) can negatively regulate T-cell function and serve as a prognostic or predictive marker in a variety of cancers. However, rare studies have evaluated the potential roles of sPD-L1, and no study has estimated its predictive value for the efficacy of immune treatment in colorectal cancer (CRC).

METHODS

Plasma samples from 192 CRC patients were used to estimate correlations between clinicopathological features and sPD-L1, secreted PD-L1 (secPD-L1) and exosomal PD-L1 (exoPD-L1). Baseline and posttreatment sPD-L1 levels were also investigated in 55 patients with metastatic CRC (mCRC) treated with chemotherapy ± targeted therapy and 40 patients with proficient mismatch repair (pMMR) mCRC treated with combination immunotherapy. Both sPD-L1 and secPD-L1 were quantified by enzyme-linked immunosorbent assay, while exoPD-L1 was analyzed using flow cytometry.

RESULTS

secPD-L1 was the major component and positively correlated with sPD-L1 in CRC, while exoPD-L1 was almost undetectable. Higher levels of sPD-L1 were detected in patients with distant metastasis, especially those with distant lymph node metastasis and tissue combined positive score (CPS) instead of tumor proportion score (TPS). Chemotherapy or targeted therapy did not significantly impact sPD-L1 concentration. Progressive disease on combination immunotherapy was associated with an increase in sPD-L1 level, whereas no significant change was observed in patients with durable clinical benefit.

CONCLUSION

sPD-L1 mainly consisted of secPD-L1, and its level was higher in patients with distant metastasis, especially distant lymph node metastasis and positive CPS. sPD-L1 is a potential dynamic marker to identify rapid progression on combination immunotherapy and avoid ineffective treatment for pMMR CRC.

Effect of Chemotherapeutics on In Vitro Immune Checkpoint Expression in Non-Small Cell Lung Cancer

Objectives: Immune checkpoint (ICP) expression in tumor cells could directly or indirectly affect the results of immunotherapy. ICP ligands on tumor cells usually bind their immune cell receptors to inhibit the activity, resulting in tumor immune escape. Thus, the purpose of this study was to ascertain the impact of various chemotherapeutic drugs on ICP expression in non-small cell lung cancer (NSCLC) cell lines with different pathological subtypes to provide a basis for the development of a superior regimen of chemotherapy combined with ICP blockade. Methods: Several first-line chemotherapy agents (cisplatin, carboplatin, paclitaxel, gemcitabine, vinorelbine, and pemetrexed) were selected to treat different NSCLC cell lines (squamous carcinoma H1703, adenocarcinoma A549, and large cell cancer H460) for 72 hours, and then the changes in ICP expression in the tumor cells were observed through flow cytometry. Results: Cisplatin, carboplatin, and paclitaxel upregulated the expressions of programmed cell death ligand 1 (PD-L1) and programmed cell death ligand 2 (PD-L2) in A549 and H460 cell lines. Meanwhile, vinorelbine and pemetrexed upregulated PD-L1 and PD-L2 in H1703, A549, and H460 cell lines. Paclitaxel, gemcitabine, vinorelbine, and pemetrexed significantly upregulated the expressions of both galectin-9 and high-mobility group box protein 1 (HMGB1) in the A549 cell line. Cisplatin and paclitaxel significantly upregulated the expressions of major histocompatibility complex-II (MHC-II), galectin-3, α-synuclein, and fibrinogen-like protein 1 (FGL1) in A549 and H460 cell lines. In addition, cisplatin and vinorelbine significantly upregulated the expressions of both CD155 and CD112 in the H460 cell line. Vinorelbine upregulated MHC-I in all three cell lines. Conclusion: Chemotherapy agents have different effects on the expression of ICP ligands in tumor cells with different pathological types, and this may affect the efficacy of combined immunotherapy. These results provide a theoretical basis for further selection and optimization of the combination of chemotherapy and immunotherapy.

KRAS G12 isoforms exert influence over up-front treatments: A retrospective, multicenter, Italian analysis of the impact of first-line immune checkpoint inhibitors in an NSCLC real-life population

BACKGROUND

KRAS is commonly mutated in non-small cell lung cancer (NSCLC); however, the prognostic and predictive impact of each G12 substitution has not been fully elucidated. The approval of specific G12C inhibitors has modified the idea of KRAS "undruggability", and although the first-line standard consists of immune checkpoint inhibitors (ICIs) with or without chemotherapy, as suggested at ASCO 2022, the outcome in KRAS-mutated population is still controversial.

METHODS

We retrospectively described the clinical and pathological characteristics of a homogeneous G12 mutated cohort of 219 patients treated in four Italian oncologic units. We evaluated the outcome (PFS at 18 months and OS at 30 months) of those who underwent standard first-line treatment according to PD-L1 status, focusing on differences across single mutations.

RESULTS

In the study population, 47.9% of patients harbor the KRAS G12C mutation; 20.5%, G12V; 17.4%, G12D; and 8.2%, G12A. Smoking was a common behavior of patients harboring transversions and transition mutations. PD-L1 expression does not show particular distribution in the case series, although we recorded a prevalence of PD-L1 <1% in G12V (51.4%) compared to G12A (26.7%). ICIs alone was the clinician's choice in 32.7% of patients, and the chemo-immune combination in 17.3% of patients. We described the independent prognostic role of young age (p = 0.007), female gender (p = 0.016), and an ICI-based regimen (p = 0.034) regardless of mutations. Overall, our data confirm the worst prognostic value of G12V mutation apart from treatment choice unlike the other major mutations (C, D, and A) that showed a favorable trend in PFS.

CONCLUSIONS

KRAS G12 mutations are confirmed to have different characteristics, and the outcome is influenced by ICI first-line regimen. This study provides valuable information for further analysis in the future.

Schedule-Dependent Treatment Increases Chemotherapy Efficacy in Malignant Pleural Mesothelioma

Malignant pleural mesothelioma (MPM) is a rare but aggressive thoracic malignancy with limited treatment options. One of the standard treatments for MPM is chemotherapy, which consists of concurrent treatment with pemetrexed and cisplatin. Pemetrexed limits tumor growth by inhibiting critical metabolic enzymes involved in nucleotide synthesis. Cisplatin causes direct DNA damage, such as intra-strand and inter-strand cross-links, which are repaired by the nucleotide excision repair pathway, which depends on relatively high nucleotide levels. We hypothesized that prolonged pretreatment with pemetrexed might deplete nucleotide pools, thereby sensitizing cancer cells to subsequent cisplatin treatment. The MPM cell lines ACC-MESO-1 and NCI-H28 were treated for 72 h with pemetrexed. Three treatment schedules were evaluated by initiating 24 h of cisplatin treatment at 0 h (concomitant), 24 h, and 48 h relative to pemetrexed treatment, resulting in either concomitant administration or pemetrexed pretreatment for 24 h or 48 h, respectively. Multicolor flow cytometry was performed to detect γH2AX (phosphorylation of histone H2AX), a surrogate marker for the activation of the DNA damage response pathway. DAPI staining of DNA was used to analyze cell cycle distribution. Forward and side scatter intensity was used to distinguish subpopulations based on cellular size and granularity, respectively. Our study revealed that prolonged pemetrexed pretreatment for 48 h prior to cisplatin significantly reduced long-term cell growth. Specifically, pretreatment for 48 h with pemetrexed induced a cell cycle arrest, mainly in the G2/M phase, accumulation of persistent DNA damage, and induction of a senescence phenotype. The present study demonstrates that optimizing the treatment schedule by pretreatment with pemetrexed increases the efficacy of the pemetrexed-cisplatin combination therapy in MPM. We show that the observed benefits are associated with the persistence of treatment-induced DNA damage. Our study suggests that an adjustment of the treatment schedule could improve the efficacy of the standard chemotherapy regimen for MPM and might improve patient outcomes.

Immunotherapy-chemotherapy combinations for non-small cell lung cancer: current trends and future perspectives

INTRODUCTION

In recent years, immunotherapy has become a pillar in the treatment of advanced, non-oncogene-addicted non-small cell lung cancer (NSCLC). Programmed death ligand 1 (PD-L1) expression is currently the only factor used to predict response to immunotherapy in clinical practice. Specifically, single agent pembrolizumab as first line therapy is approved for tumors with high expression of PD-L1 (≥50%) while immunotherapy and chemotherapy are approved for any PD-L1. However, combinations of immune-checkpoint inhibitors (ICIs) and other agents may confer higher benefit than immunotherapy alone in some circumstances.

AREAS COVERED

We reviewed the available data regarding the combined use of ICIs and chemotherapy in patients with advanced, treatment-naïve NSCLC. In light of the benefit demonstrated in advanced disease, these combinations have been subsequently tested in other settings. We collected the most relevant findings regarding efficacy and safety of chemo-immunotherapy combinations in early and locally advanced NSCLC.

EXPERT OPINION

Immune-chemotherapy combinations demonstrated benefit in the advanced setting, and this strategy in now being applied in the early and local advanced settings. A description of clinical and biological predictors of response is required in order to identify patients who may benefit the most from combination therapy.

Identification and validation of Osteopontin and receptor for hyaluronic acid-mediated motility (RHAMM, CD168) for potential immunotherapeutic significance of in lung squamous cell carcinoma

BACKGROUND

Lung cancer is the leading cause of cancer-related deaths. Immunotherapy is a promising therapeutic approach, but the population best suited to immunotherapy is yet to be determined.

MATERIALS AND METHODS

Lung squamous cell carcinoma (LUSC) was chosen as the object for the present study. Four gene expression profiles were retrieved from the GEO database. 141 differentially expressed genes (DEGs) were detected in LUSC tissues and normal tissues by the GEO2R tool and Venn diagram software.

RESULTS

34 candidate genes were selected for further analysis. A Kaplan-Meier survival plot further isolated 29 of 34 genes and after re-validation using gene expression profiling interactive analysis and pathway enrichment, Bonferroni correction was used to adjust P values, results showed that two genes (CD168 and OPN) were markedly enriched in the extracellular matrix (ECM)-receptor interaction pathway. We believe this pathway and genes may be tightly involved in the LUSC tumor immune microenvironment. We conducted a further cellular study to knock-down OPN in H520 cells using siRNA. The expression of CD168 was reduced in siRNA-OPN H520 cells (P < 0.05). Our results indicate that the arrest of CD168 occurs after the downregulation of the OPN protein, suggesting that OPN participates in ECM-receptor interactions.

CONCLUSIONS

By using integrated bioinformatics, we have identified CD168 and OPN as DEGs with poor prognosis in LUSC and have validated their interaction in the ECM receptor pathway. These genes could be potential diagnostic and therapeutic targets for LUSC patients undergoing immunotherapy.

First-line chemotherapy plus immune checkpoint inhibitors or bevacizumab in advanced non-squamous non-small-cell lung cancer without EGFR mutations or ALK fusions

Aim: To compare the efficacy and safety of first-line chemotherapy (Chemo) plus immune checkpoint inhibitors (ICIs) or bevacizumab (Bev) in advanced non-squamous non-small-cell lung cancer without EGFR mutations or ALK fusions. Methods: A network meta-analysis was conducted to synthesize relative treatment outcomes. Results: Chemo + ICIs is superior to Chemo + Bev in both overall survival (hazard ratio: 0.92; 95% CI: 0.88-0.96) and progression-free survival (hazard ratio: 0.93; 95% CI: 0.90-0.97), with comparable severe adverse events. However, for patients with liver metastasis, Chemo + Bev has a 59.8% probability of providing better overall survival benefit. For specific regimens, pembrolizumab + Chemo showed an absolute advantage over other regimens. Conclusion: First-line Chemo + ICIs is superior to Chemo + Bev in advanced non-squamous non-small-cell lung cancer except for patients with liver metastasis.

The generation of PD-L1 and PD-L2 in cancer cells: From nuclear chromatin reorganization to extracellular presentation

The immune checkpoint blockade (ICB) targeting on PD-1/PD-L1 has shown remarkable promise in treating cancers. However, the low response rate and frequently observed severe side effects limit its broad benefits. It is partially due to less understanding of the biological regulation of PD-L1. Here, we systematically and comprehensively summarized the regulation of PD-L1 from nuclear chromatin reorganization to extracellular presentation. In PD-L1 and PD-L2 highly expressed cancer cells, a new TAD (topologically associating domain) (chr9: 5,400,000-5,600,000) around CD274 and CD273 was discovered, which includes a reported super-enhancer to drive synchronous transcription of PD-L1 and PD-L2. The re-shaped TAD allows transcription factors such as STAT3 and IRF1 recruit to PD-L1 locus in order to guide the expression of PD-L1. After transcription, the PD-L1 is tightly regulated by miRNAs and RNA-binding proteins via the long 3'UTR. At translational level, PD-L1 protein and its membrane presentation are tightly regulated by post-translational modification such as glycosylation and ubiquitination. In addition, PD-L1 can be secreted via exosome to systematically inhibit immune response. Therefore, fully dissecting the regulation of PD-L1/PD-L2 and thoroughly detecting PD-L1/PD-L2 as well as their regulatory networks will bring more insights in ICB and ICB-based combinational therapy.

Dramatic response to immunotherapy in an epidermal growth factor receptor-mutant non-small cell lung cancer: A case report

BACKGROUND

The advent of immune checkpoint inhibitors (ICIs) has revolutionized the management of several types of solid cancers, including lung cancer, by boosting the body's natural tumor killing response. However, it is undeniable that only a small proportion of non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) mutations can achieve long-term responses and benefit from immunotherapy.

CASE SUMMARY

Herein, we report the case of a 48-year-old man diagnosed with stage IV lung adenocarcinoma with an EGFR L858R mutation who was administered pembrolizumab monotherapy followed by pemetrexed and achieved a 10-month progression-free survival interval. In this case report, we show that ICIs were effective for our patient with EGFR-mutated NSCLC and discuss the characteristics of patients who can benefit from immunotherapy.

CONCLUSION

We suggest that patients with EGFR-mutated NSCLC with high PD-L1 expression (defined as ≥ 25%), the L858R mutation, smoking history, or pemetrexed pretreatment may benefit from immunotherapy.

Multicellular Effects of STAT3 in Non-small Cell Lung Cancer: Mechanistic Insights and Therapeutic Opportunities

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer and accounts for 85% of lung cancer cases. Aberrant activation of the Signal Transducer and Activator of Transcription 3 (STAT3) is frequently observed in NSCLC and is associated with a poor prognosis. Pre-clinical studies have revealed an unequivocal role for tumor cell-intrinsic and extrinsic STAT3 signaling in NSCLC by promoting angiogenesis, cell survival, cancer cell stemness, drug resistance, and evasion of anti-tumor immunity. Several STAT3-targeting strategies have also been investigated in pre-clinical models, and include preventing upstream receptor/ligand interactions, promoting the degradation of STAT3 mRNA, and interfering with STAT3 DNA binding. In this review, we discuss the molecular and immunological mechanisms by which persistent STAT3 activation promotes NSCLC development, and the utility of STAT3 as a prognostic and predictive biomarker in NSCLC. We also provide a comprehensive update of STAT3-targeting therapies that are currently undergoing clinical evaluation, and discuss the challenges associated with these treatment modalities in human patients.

An Indirect Comparison Between Nivolumab + Ipilimumab + Two Cycles of Chemotherapy vs. Pembrolizumab + Chemotherapy as First-Line Treatment for Metastatic Non-Small Cell Lung Cancer

BACKGROUND

Nivolumab + ipilimumab + two cycles chemotherapy (N-I + chemo, intensive immunotherapy but chemo-light) and pembrolizumab + chemotherapy (Pem + chemo) were both recommended as first-line treatment for metastatic non-small cell lung carcinoma (NSCLC) patients. We conducted this indirect comparison to compare the efficacy of and safety between these two treatments for providing reference for decision making.

METHODS

Relevant databases were searched for eligible trials. A well-accepted adjusted indirect treatment comparison (ITC) approach was selected to pool efficacy results and safety outcomes. Subgroup analyses were stratified according to PD-L1 expression and clinical characteristics.

RESULTS

Four eligible randomized trials (CheckMate9LA, KEYNOTE-021G, KEYNOTE 189, KEYNOTE 407) involving 2017 patients were available to analyze. The ITC results suggested that N-I + chemo is comparable to Pem + chemo in OS (HR 1.03, 95% CI 0.82-1.30) and ORR (RR 0.81, 95% CI 0.62-1.06), but tended to yield inferior PFS (HR 1.28, 95% CI 1.04-1.59) than did Pem + chemo. As for safety profiles, N-I + chemo showed no significant difference relative to Pem + chemo in any grade adverse events: (RR 1.03, 95% CI 0.99-1.10), but demonstrated reduced toxicity in chemo-related adverse events, such as anemia (RR 0.63, 95% CI 0.49-0.81), neutropenia (RR0.51, 95% CI 0.33-0.79), and thrombocytopenia (RR 0.38, 95% CI 0.21-0.69).

CONCLUSIONS

N-I + chemo is a promising treatment option for providing comparable OS related to Pem + chemo. However, for never smoker female patients, Pem + chemo is preferable to choose for demonstrating favorable OS benefit than N-I + chemo.

Cisplatin remodels the tumor immune microenvironment via the transcription factor EB in ovarian cancer

The mortality rate of ovarian cancer (OC) remains the highest among all gynecological malignancies. Platinum-based chemotherapies are effective in treating most OC cases. However, chemoresistance is still a major challenge for successful OC treatments. Emerging evidence has highlighted that the modulation of the tumor immune microenvironment is involved in chemoresistance, but the mechanism remains unclear. This study aimed to investigate whether resistance to cisplatin (CDDP), the standard treatment for OC, is due to the remodeling of the tumor immune microenvironment by the transcription factor EB (TFEB). We hypothesized that TFEB is not essential for tumor survival but is associated with CDDP resistance. We collected 20 tissue samples of OC patients who had not undergone chemotherapy or radiotherapy prior to surgery. We cultured OC cell lines and performed cell transfection and assays as well as analytical, fluorescence microscopy, and immunohistochemical techniques to explore a novel function of TFEB in remodeling the tumor immune microenvironment in OC. We found a positive correlation between TFEB and programmed cell death-ligand 1 (PD-L1), PD-L2, and HLA-A expression in OC cells and tissues. We also found that CDDP treatment induced TFEB nuclear translocation, thus increasing PD-L1 and PD-L2 expression to foster an immunosuppressive tumor microenvironment, which mediates tumor immune evasion and drug resistance. Interestingly, TFEB also regulated HLA-A expression, which increases the tumor immunogenicity of OC. Finally, in a syngenic murine model of OC, we observed the therapeutic benefit of CDDP plus programmed cell death-1 (PD-1) inhibitor, which enhanced the cytolytic activity of CD8⁺ T cells and inhibited tumor growth. Our study illustrates the important role of TFEB in regulating the tumor immune microenvironment in OC.

Down-regulation of RCC1 sensitizes immunotherapy by up-regulating PD-L1 via p27kip1 /CDK4 axis in non-small cell lung cancer

In recent years, although Immune Checkpoint Inhibitors (ICIs) significantly improves survival both in local advanced stage and advanced stage of non-small cell lung cancer (NSCLC), the objective response rate of ICI monotherapy is still only about 20%. Thus, to identify the mechanisms of ICI resistance is critical to increase the efficacy of ICI treatments. By bioinformatics analysis, we found that the expression of regulator of chromosome condensation 1 (RCC1) in lung adenocarcinoma was significantly higher than that in normal lung tissue in TCGA and Oncomine databases. The survival analysis showed that high expression RCC1 was associated with the poor prognosis of NSCLC. And the expression of RCC1 was inversely related to the number of immune cell infiltration. In vitro, knockdown of RCC1 not only significantly inhibited the proliferation of lung adenocarcinoma cells but also increased the expression levels of p27^kip1 and PD-L1, and decreased the expression level of CDK4 and p-Rb. In vivo, knockdown of RCC1 significantly slowed down the growth rate of tumour, and further reduced the volume and weight of tumour model after treated by PD-L1 monoclonal antibody. Therefore, RCC1 could up-regulate the expression level of PD-L1 by regulating p27^kip1 /CDK4 pathway and decrease the resistance to ICIs. And this study might provide a new way to increase the efficacy of PD-L1 monoclonal antibody by inhibiting RCC1.

The Mechanisms of PD-L1 Regulation in Non-Small-Cell Lung Cancer (NSCLC): Which Are the Involved Players?

Treatment with inhibition of programmed cell death 1 (PD-1) or its ligand (PD-L1) improves survival in advanced non-small-cell lung cancer (NSCLC). Nevertheless, only a subset of patients benefit from treatment and biomarkers of response to immunotherapy are lacking. Expression of PD-L1 on tumor cells is the primary clinically-available predictive factor of response to immune checkpoint inhibitors, and its relevance in cancer immunotherapy has fostered several studies to better characterize the mechanisms that regulate PD-L1 expression. However, the factors associated with PD-L1 expression are still not well understood. Genomic alterations that activate KRAS, EGFR, and ALK, as well as the loss of PTEN, have been associated with increased PD-L1 expression. In addition, PD-L1 expression is reported to be increased by amplification of CD274, and decreased by STK11 deficiency. Furthermore, PD-L1 expression can be modulated by either tumor extrinsic or intrinsic factors. Among extrinsic factors, the most prominent one is interferon-γ release by immune cells, while there are several tumor intrinsic factors such as activation of the mechanistic target of rapamycin (mTOR), mitogen-activated protein kinase (MAPK) and Myc pathways that can increase PD-L1 expression. A deeper understanding of PD-L1 expression regulation is crucial for improving strategies that exploit inhibition of this immune checkpoint in the clinic, especially in NSCLC where it is central in the therapeutic algorithm. We reviewed current preclinical and clinical data about PD-L1 expression regulation in NSCLC.

Efficacy of natural killer cell activity as a biomarker for predicting immunotherapy response in non-small cell lung cancer

Background

The establishment of biomarkers that can be used to predict the response to immunotherapy for malignancy is extremely important. In particular, noninvasive analysis of immune cells from peripheral blood before treatment has gained increased attention, and natural killer (NK) cell activity has been shown to be related to treatment response. Here, we aimed to confirm the relationship between the response to immunotherapy and NK cell activity.

Methods

In this prospective observational study, patients with advanced NSCLC who were scheduled for immunotherapy from October 2018 to December 2019 were enrolled. Baseline NK cell activity was compared according to the best clinical response to immunotherapy.

Results

A total of 54 patients with advanced NSCLC were enrolled, and 34 patients were analyzed. The baseline NK cell activity was significantly higher in the non‐PD group than in the PD group (P = 0.002). At the cutoff level of ≥1200 pg/mL, baseline NK cell activity yielded a sensitivity of 80% and a specificity of 68.4% in predicting the response to immunotherapy (AUC = 0.8, P < 0.003). The median progression‐free survival (PFS) was significantly better in the high NK group (P = 0.003), and correlation between baseline NK cell activity and PFS was also confirmed (r = 0.517, P = 0.002).

Conclusions

Baseline NK cell activity was related to the response to immunotherapy and the PFS. We suggest that NK cell activity from peripheral blood before immunotherapy is a noninvasive, simple, and novel way to predicting the treatment response in patients with NSCLC.

Key points

Significant findings of the study

The response to immunotherapy was significantly better in patients with high baseline NK cell activity, and there was a significant correlation between baseline NK cell activity and PFS.

What this study adds

This study demonstrates the efficacy of baseline NK cell activity from peripheral blood as a biomarker for predicting immunotherapy response.