Combination therapy with PD-1 or PD-L1 inhibitors for cancer

Neoadjuvant Treatment in Muscle-Invasive Bladder Cancer: From the Beginning to the Latest Developments

Urothelial carcinoma of the bladder is one of the most prevalent cancers worldwide, diagnosed as muscle invasive in 25% of cases. Although several studies have demonstrated an overall 5% absolute survival benefit at 5 years with cisplatin-based combination neoadjuvant treatment, administration of chemotherapy prior to radical cystectomy (RC) in muscle-invasive bladder cancer (MIBC) patients is still a matter of debate. This may be due to the perceived modest survival benefit, cisplatin-based chemotherapy ineligibility, or fear of delaying potentially curative surgery in non-responders. However, immunotherapy and novel targeted therapies have shown to prolong survival in advanced disease and are under investigation in the neoadjuvant and adjuvant settings to reduce systemic relapse and improve cure rates. Genomic characterization of MIBC could help select the most effective chemotherapeutic regimen for the individual patient. Large cohort studies on neoadjuvant treatments with immune checkpoint inhibitors (ICIs) and molecular therapies, alone or combined with chemotherapy, are ongoing. In this review, we trace the development of neoadjuvant therapy in MIBC and explore recent advances that may soon change clinical practice.

Correlation between PD-1/PD-L1 expression and polarization in tumor-associated macrophages: A key player in tumor immunotherapy

Tumor immunotherapy, such as PD-1/PD-L1 blockade, has shown promising clinical efficacy in patients with various types of tumors. However, the response to PD-1/PD-L1 blockade in a majority of malignancies is limited, indicating an urgent need for a deeper understanding of the mechanisms of PD-1/PD-L1 axis-mediated tumor tolerance. As the most abundant immune cells in the tumor stroma, macrophages display multiple phenotypes and functions in response to the stimuli of the tumor microenvironment. PD-1/PD-L1 has been demonstrated to be highly expressed in tumor-associated macrophages (TAMs), and TAM polarization has been shown to be important during tumor progression. In this review, we outline the relationship between TAM PD-1/PD-L1 expression and polarizations, summarize the involvement of M2 TAMs in PD-1/PD-L1-mediated T-cell exhaustion, and discuss improved approaches for overcoming PD-1/PD-L1 blockade resistance by inducing M2/M1 switching of TAMs.

Thyroid dysfunction during PD‑1 inhibitor treatment in patients with cancer: Incidence and association with progression‑free survival

The use of programmed cell death-1 (PD-1) inhibitors has recently been approved in China. As a consequence, the identification of relevant prognostic markers that can assess the efficacy of these compounds is required. Therefore, the present study aimed to explore the incidence of thyroid dysfunction and its ability to predict progression-free survival (PFS) in Chinese patients with cancer who received PD-1 inhibitor treatment. Data from 72 patients with cancer who received treatment with PD-1 inhibitors alone or in combination with chemotherapy or targeted drugs were analyzed. Moreover, the expression levels of free triiodothyronine, thyroxine, and thyrotropin during treatment were assessed to evaluate thyroid dysfunction. A total of 26 (36.1%) patients who had received PD-1 inhibitors developed thyroid dysfunction. Specifically, the incidence of thyroid dysfunction was 35.6% in patients with lung cancer, 25.0% in patients with malignant melanoma, and 46.7% in patients with other types of cancer. In addition, the median PFS was 7.0 (95% confidence interval, 4.9-9.1) months, whereas the 1- and 2-year PFS rates were 35.1 and 26.2%, respectively. Generally, patients with thyroid dysfunction exhibited longer PFS compared with those without thyroid dysfunction (P=0.001). Subgroup analyses were subsequently performed, which demonstrated that thyroid dysfunction was associated with longer PFS in patients with malignant melanoma (P=0.039) and other types of cancer (P=0.002), but not in those with lung cancer (P=0.083). These findings were noted in patients who received PD-1 inhibitor monotherapy (P=0.003), but not PD-1 inhibitor plus chemotherapy (P=0.172) or PD-1 inhibitor plus targeted therapy (P=0.582). Finally, thyroid dysfunction [P=0.001; hazard ratio (HR)=0.260] and PD-1 inhibitor monotherapy (P=0.015; HR=2.231) were identified as independent factors that could predict PFS. In conclusion, the present study demonstrated that thyroid dysfunction during PD-1 inhibitor treatment could be used as a potential marker for the prognosis of favorable PFS in patients with cancer.

Liposomal Co-delivery of PD-L1 siRNA/Anemoside B4 for Enhanced Combinational Immunotherapeutic Effect

Combination therapy has gained a lot of attention thanks to its superior activity against cancer. In the present study, we report a cRGD-targeted liposomal preparation for co-delivery of programmed cell death ligand 1 (PD-L1) small interfering RNA (siRNA) and anemoside B4 (AB4)─AB4/siP-c-L─and evaluate its anticancer efficiency in mouse models of LLC and 4T1 tumors. AB4/siP-c-L showed a particle size of (180.7 ± 7.3) nm and a ζ-potential of (32.8 ± 1.5) mV, with high drug encapsulation, pH-sensitive release properties, and good stability in serum. AB4/siP-c-L demonstrated prolonged blood circulation and increased tumor accumulation. Elevated cellular uptake was dependent on the targeting ligand cRGD. This combination induced significant tumor inhibition in LLC xenograft tumor-bearing mice by downregulating PD-L1 protein expression and modulating the immunosuppressive microenvironment. Liposomes favored the antitumor T-cell response with long-term memory, without obvious toxicity. A similar tumor growth inhibition was also demonstrated in the 4T1 tumor model. In summary, our results indicate that cRGD-modified and AB4- and PD-L1 siRNA-coloaded liposomes have potential as an antitumor preparation, and this approach may lay a foundation for the development of a new targeted drug delivery system.

Comprehensive Analysis Identifies PI3K/Akt Pathway Alternations as an Immune-Related Prognostic Biomarker in Colon Adenocarcinoma Patients Receiving Immune Checkpoint Inhibitor Treatment

Introduction

In recent years, immune checkpoint inhibitors (ICIs) have attracted widespread attention and made breakthroughs in progress towards the treatment of various cancers. However, ICI therapy is selective, and its effects on many patients are not ideal. It is therefore critical to identify prognostic biomarkers of response to ICI therapy. The PI3K/Akt pathway plays important roles in tumor formation and metastasis. However, there are no published reports clarifying the relationship between PI3K/Akt pathway mutations and prognosis for colon adenocarcinoma (COAD) patients receiving immunotherapy.

Methods

We collected data from a COAD cohort from The Cancer Genome Atlas (TCGA) database, including whole-exome sequencing (WES) data, RNA-seq data, and clinical data. We also collected data, including clinical prognosis and targeted sequencing data, from a cohort of COAD patients receiving immunotherapy. We collected 50 COAD patients (Local-COAD) from the Zhujiang Hospital of Southern Medical University and performed targeted sequencing. We analyzed the effects of PI3K/Akt pathway mutations on the patients' clinical prognosis, immunogenicity, and immune microenvironments. Gene set enrichment analysis (GSEA) was used to analyze the significantly upregulated and downregulated signaling pathways. We used these results to hypothesize potential mechanisms by which PI3K/Akt mutations could affect the prognosis of COAD patients.

Results

Univariate and multivariate Cox analyses and Kaplan-Meier (KM) survival curves showed that patients with PI3K-Akt mutations had better overall survival (OS) than those without PI3K-Akt mutations. Genes with significant mutation rates in the two cohorts were screened by panoramic view. CIBERSORT was used to analyze changes in 22 types of immune cells to identify immune activated cells. Similarly, patients in the PI3K/Akt-mutated type (PI3K/Akt-MT) group had significantly increased immunogenicity, including increases in tumor mutation burden (TMB), neoantigen load (NAL), and MANTIS score. Using GSEA, we identified upregulated pathways related to immune response.

Conclusion

PI3K/Akt pathway mutation status can be used as an independent predictor of response to ICI treatment in COAD patients. PI3K/Akt mutations are correlated with improved OS, higher immunogenicity, greater immune response scores, and increases in activated immune cells.

Pharmacologic Tumor PDL1 Depletion with Cefepime or Ceftazidime Promotes DNA Damage and Sensitivity to DNA-Damaging Agents

The interaction between tumor surface-expressed PDL1 and immune cell PD1 for the evasion of antitumor immunity is well established and is targeted by FDA-approved anti-PDL1 and anti-PD1 antibodies. Nonetheless, recent studies highlight the immunopathogenicity of tumor-intrinsic PDL1 signals that can contribute to the resistance to targeted small molecules, cytotoxic chemotherapy, and αPD1 immunotherapy. As genetic PDL1 depletion is not currently clinically tractable, we screened FDA-approved drugs to identify those that significantly deplete tumor PDL1. Among the candidates, we identified the β-lactam cephalosporin antibiotic cefepime as a tumor PDL1-depleting drug (PDD) that increases tumor DNA damage and sensitivity to DNA-damaging agents in vitro in distinct aggressive mouse and human cancer lines, including glioblastoma multiforme, ovarian cancer, bladder cancer, and melanoma. Cefepime reduced tumor PDL1 post-translationally through ubiquitination, improved DNA-damaging-agent treatment efficacy in vivo in immune-deficient and -proficient mice, activated immunogenic tumor STING signals, and phenocopied specific genetic PDL1 depletion effects. The β-lactam ring and its antibiotic properties did not appear contributory to PDL1 depletion or to these treatment effects, and the related cephalosporin ceftazidime produced similar effects. Our findings highlight the rapidly translated potential for PDDs to inhibit tumor-intrinsic PDL1 signals and improve DNA-damaging agents and immunotherapy efficacy.

Clickable Albumin Nanoparticles for Pretargeted Drug Delivery toward PD-L1 Overexpressing Tumors in Combination Immunotherapy

We present a simple methodology to design a pretargeted drug delivery system, based on clickable anti-programmed death ligand 1 (anti-PD-L1) antibodies (Abs) and clickable bovine serum albumin (BSA) nanoparticles (NPs). Pretargeted drug delivery is based on the decoupling of a targeting moiety and a drug-delivering vector which can then react in vivo after separate injections. This may be key to achieve active targeting of drug-delivering NPs toward cancerous tissue. In pretargeted approaches, drug-delivering NPs were observed to accumulate in a higher amount in the targeted tissue due to shielding-related enhanced blood circulation and size-related enhanced tissue penetration. In this work, BSA NPs were produced using the solvent precipitation methodology that renders colloidally stable NPs, which were subsequently functionalized with a clickable moiety based on chlorosydnone (Cl-Syd). Those reactive groups are able to specifically react with dibenzocyclooctyne (DBCO) groups in a click-type fashion, reaching second-order reaction rate constants as high as 1.9 M^-1·s^-1, which makes this reaction highly suitable for in vivo applications. The presence of reactive Cl-Syd was demonstrated by reacting the functionalized NPs with a DBCO-modified sulfo-cyanine-5 dye. With this reaction, it was possible to infer the number of reactive moieties per NPs. Finally, and with the aim of demonstrating the suitability of this system to be used in pretargeted strategies, functionalized fluorescent NPs were used to label H358 cells with a clickable anti-PD-L1 Ab, applying the reaction between Cl-Syd and DBCO as corresponding clickable groups. The results of these experiments demonstrate the bio-orthogonality of the system to perform the reaction in vitro, in a period as short as 15 min.

Efficacy and Safety of Nivolumab for Advanced Renal Cell Carcinoma: A Systematic Review and Meta-Analysis

Objective

To assess the efficacy and safety of nivolumab for advanced renal cell carcinoma (RCC) via meta-analysis.

Methods

In this systematic review and meta-analysis, we searched PubMed, Embase, Science Citation Index Expanded, The Cochrane Library, and Web of Science for randomized controlled trials (RCTs) using nivolumab for patients with advanced RCC published before 30 December 2021. Quality assessments and meta-analyses were performed on all the literature assessed for eligibility.

Results

Of 203 studies identified as potentially eligible from 3214 studies in a preliminary search, three RCTs including 2550 RCC cases met the inclusion criteria and were of high quality. Meta-analysis showed benefits of nivolumab in the progression-free survival (PFS) (HR = 0.73, 95% CI: 0.54 to 0.99, P=0.04) and overall survival (OS) (HR = 0.70, 95% CI: 0.63 to 0.78, P < 0.001) of patients with advanced RCC, and no increase in documented adverse events was recorded.

Conclusion

Nivolumab plus ipilimumab has significant benefits versus sunitinib in the treatment of advanced RCC in terms of tumor progression control and prolongation of OS and PFS, with a manageable safety profile.

A novel nine-microRNA-based model to improve prognosis prediction of renal cell carcinoma

Background

With the improved knowledge of disease biology and the introduction of immune checkpoints, there has been significant progress in treating renal cell carcinoma (RCC) patients. Individual treatment will differ according to risk stratification. As the clinical course varies in RCC, it has developed different predictive models for assessing patient’s individual risk. However, among other prognostic scores, no transparent preference model was given. MicroRNA as a putative marker shown to have prognostic relevance in RCC, molecular analysis may provide an innovative benefit in the prophetic prediction and individual risk assessment. Therefore, this study aimed to establish a prognostic-related microRNA risk score model of RCC and further explore the relationship between the model and the immune microenvironment, immune infiltration, and immune checkpoints. This practical model has the potential to guide individualized surveillance protocols, patient counseling, and individualized treatment decision for RCC patients and facilitate to find more immunotherapy targets.

Methods

Downloaded data of RCC from the TCGA database for difference analysis and divided it into a training set and validation set. Then the prognostic genes were screened out by Cox and Lasso regression analysis. Multivariate Cox regression analysis was used to establish a predictive model that divided patients into high-risk and low-risk groups. The ENCORI online website and the results of the RCC difference analysis were used to search for hub genes of miRNA. Estimate package and TIMER database were used to evaluate the relationship between risk score and tumor immune microenvironment (TME) and immune infiltration. Based on Kaplan-Meier survival analysis, search for immune checkpoints related to the prognosis of RCC.

Results

There were nine miRNAs in the established model, with a concordance index of 0.702 and an area under the ROC curve of 0.701. Nine miRNAs were strongly correlated with the prognosis (P < 0.01), and those with high expression levels had a poor prognosis. We found a common target gene PDGFRA of hsa-miR-6718, hsa-miR-1269b and hsa-miR-374c, and five genes related to ICGs (KIR2DL3, TNFRSF4, LAG3, CD70 and TNFRSF9). The immune/stromal score, immune infiltration, and immune checkpoint genes of RCC were closely related to its prognosis and were positively associated with a risk score.

Conclusions

The established nine-miRNAs prognostic model has the potential to facilitate prognostic prediction. Moreover, this model was closely related to the immune microenvironment, immune infiltration, and immune checkpoint genes of RCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09322-9.

Acquired resistance for immune checkpoint inhibitors in cancer immunotherapy: challenges and prospects

Drug resistance has become an obstacle to the further development of immunotherapy in clinical applications and experimental studies. In the current review, the acquired resistance to immunotherapy was examined. The mechanisms of acquired resistance were based on three aspects as follows: The change of the tumor functions, the upregulated expression of inhibitory immune checkpoint proteins, and the effects of the tumor microenvironment. The combined use of immunotherapy and other therapies is performed to delay acquired resistance. A comprehensive understanding of acquired drug resistance may provide ideas for solving this dilemma.

Optimal first-line treatment for platinum-eligible metastatic urothelial carcinoma: Comparison of chemo-immunotherapy, immunotherapy, and chemotherapy- A systematic review and meta-analysis

BACKGROUND

The role of first-line of immunotherapy in metastatic urothelial carcinoma (mUC) remains unclear. This meta-analysis aimed to explore an optimal first-line treatment strategy for mUC patients.

METHODS

We carried out a meta-analysis between chemo-immunotherapy, immunotherapy, and chemotherapy in mUC based on randomized trials. The outcomes included overall survival (OS), progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and treatment-related adverse events (AEs). A fixed-effect or random-effects model was adopted depending on between-study heterogeneity.

RESULTS

Three trials involving 3238 patients were included. PD-1/PD-L1 inhibitor plus platinum-based chemotherapy was associated with the improvements of OS (HR, 0.85; 95% CI 0.75-0.99), PFS (HR, 0.80; 95% CI 0.71-0.90) and ORR (OR, 1.32; 95% CI 1.07-1.63) when compared with platinum-based chemotherapy, but not with better DCR (OR, 1.07; 95% CI 0.78-1.46). PD-1/PD-L1 inhibitor alone was associated with worse ORR (OR, 0.38; 95% CI 0.17-0.87) and DCR (OR, 0.20; 95% CI 0.16-0.25) when compared with platinum-based chemotherapy while it did not statistically reduce the risk of mortality (HR 0.97 for entire cohort; 0.90 for PD-L1 high cohort). In safety analyses, the incidence of adverse events (AEs) between regimens showed no difference, but the frequency of AEs of grade 3 or severity was higher in chemo-immunotherapy compared to chemotherapy.

CONCLUSIONS

Compared with platinum-based chemotherapy, chemo-immunotherapy is associated with significantly improved PFS, OS, and ORR in the first-line therapy for mUC at the expanse of increased toxicity.

Retrospective analysis of the preparation and application of immunotherapy in cancer treatment (Review)

Monoclonal antibody technology plays a vital role in biomedical and immunotherapy, which greatly promotes the study of the structure and function of genes and proteins. To date, monoclonal antibodies have gone through four stages: murine monoclonal antibody, chimeric monoclonal antibody, humanised monoclonal antibody and fully human monoclonal antibody; thousands of monoclonal antibodies have been used in the fields of biology and medicine, playing a special role in the pathogenesis, diagnosis and treatment of disease. In this review, we compare the advantages and disadvantages of hybridoma technology, phage display technology, ribosome display technology, transgenic mouse technology, single B cell monoclonal antibody generation technologies, and forecast the promising applications of these technologies in clinical medicine, disease diagnosis and tumour treatment.

Immune Checkpoint Inhibitor-Associated Colitis: From Mechanism to Management

Immune checkpoint inhibitors (ICIs), as one of the innovative types of immunotherapies, including programmed cell death-1 (PD-1), programmed cell death-ligand 1 (PD-L1), and cytotoxic T lymphocyte antigen 4 (CTLA-4) inhibitors, have obtained unprecedented benefit in multiple malignancies. However, the immune response activation in the body organs could arise immune-related adverse events (irAEs). Checkpoint inhibitor colitis (CIC) is the most widely reported irAEs. However, some obscure problems, such as the mechanism concerning gut microbiota, the confusing differential diagnosis with inflammatory bowel disease (IBD), the optimal steroid schedule, the reintroduction of ICIs, and the controversial prognosis features, influence the deep understanding and precise diagnosis and management of CIC. Herein, we based on these problems and comprehensively summarized the relevant studies of CIC in patients with NSCLC, further discussing the future research direction of this specific pattern of irAEs.

USP5 facilitates non-small cell lung cancer progression through stabilization of PD-L1

PD-L1(CD274) is a well-known immunosuppressive molecule, which confers immunoescape features to cancer cells and has become one of the major targets in cancer immunotherapies. Understanding the regulatory mechanisms that control PD-L1 protein expression is important for guiding immune checkpoint blockade therapy. Here, we showed that ubiquitin specific peptidase 5 (USP5) was a novel PD-L1 deubiquitinase in non-small cell lung cancer (NSCLC) cells. USP5 directly interacted with PD-L1 and deubiquitinated PD-L1, therefore enhances PD-L1 protein stability. Meanwhile, USP5 protein levels were highly elevated and positively correlated to PD-L1 levels in NSCLC tissues, and were closely correlated with poor prognosis of these patients. In addition, knockdown of USP5 retarded tumor growth in the Lewis lung carcinoma mouse model. Thus, we identified that USP5 was a new regulator of PD-L1 and targeting USP5 is a promising strategy for cancer therapy.

Elemene Nanoemulsion Inhibits Metastasis of Breast Cancer by ROS Scavenging

Introduction

Elemene (C₁₅H₂₄) is a sesquiterpene compound extracted from the rhizome of Curcuma herbs. In the past decades, the anti-tumor activity of elemene has been observed in vitro and in some clinical practices. However, pharmacological mechanisms of elemene are not demonstrated adequately, which may lead to improper clinical applications. This study aimed to investigate the anti-tumor effect of elemene nanoemulsion in the mouse model of triple-negative breast cancer (TNBC) and reveal the underlying mechanisms.

Methods

The ESR measurement and quantum mechanics simulation were used to characterize the antioxidant ability of elemene nanoemulsion. The murine breast cancer cell line 4T1 cells were inoculated subcutaneously into the left fourth mammary fat pad of BalB/c mice to establish a TNBC mice model. The H&E staining, immunohistochemical staining, DHE staining and Western blot were employed to evaluate the therapeutic effects of the elemene nanoemulsion on the TNBC mice.

Results

It was shown that the elemene nanoemulsion prolonged the survival of the triple-negative breast cancer-bearing mice and inhibited the metastasis to lung and liver while did not induce significant cytotoxicity to the tumor cells. Mechanistic studies demonstrated that the elemene nanoemulsion effectively scavenged the reactive oxygen species (ROS) in vitro and in vivo, which decreased the stabilization of hypoxia-inducible factor-1α (HIF-1α) and consequently reduced angiogenesis in the tumor microenvironment as well as decreased the level of NLRP3 inflammasomes and IL-1β production. In addition, the elemene nanoemulsion downregulated the level of IL-1β in the RAW264.7 cells in exposure with LPS.

Conclusion

In conclusion, due to the ROS scavenging ability, elemene nanoemulsion effectively inhibited the metastasis of the breast cancer cells to lung and liver and consequently prolonged the survival of TNBC mice.

MSI testing : What's new? What should be considered?

Based on new trial data regarding immune checkpoint inhibitors (ICIs), the detection of high-grade microsatellite instability (MSI-H) or underlying deficient mismatch repair protein (dMMR) is now becoming increasingly important for predicting treatment response. For the first time, a PD‑1 ICI (pembrolizumab) has been approved by the European Medicines Agency (EMA) for first-line treatment of advanced (stage IV) dMMR/MSI‑H colorectal cancer (CRC). Further indications, such as dMMR/MSI‑H endometrial carcinoma (EC), have already succeeded (Dostarlimab, 2nd line treatment) and others are expected to follow before the end of 2021. The question of optimal testing in routine diagnostics should therefore be re-evaluated. Based on a consideration of the strengths and weaknesses of the widely available methods (immunohistochemistry and PCR), a test algorithm is proposed that allows quality assured, reliable, and cost-effective dMMR/MSI‑H testing. For CRC and EC, testing is therefore already possible at the primary diagnosis stage, in line with international recommendations (NICE, NCCN). The clinician is therefore enabled from the outset to consider not only the predictive but also the prognostic and predispositional implications of such a test when counseling patients and formulating treatment recommendations. As a basis for quality assurance, participation in interlaboratory comparisons and continuous documentation of results (e.g., QuIP Monitor) are strongly recommended.

Local Therapies and Modulation of Tumor Surrounding Stroma in Malignant Pleural Mesothelioma: A Translational Approach

Malignant Pleural Mesothelioma (MPM) is a rare and aggressive neoplasm of the pleural mesothelium, mainly associated with asbestos exposure and still lacking effective therapies. Modern targeted biological strategies that have revolutionized the therapy of other solid tumors have not had success so far in the MPM. Combination immunotherapy might achieve better results over chemotherapy alone, but there is still a need for more effective therapeutic approaches. Based on the peculiar disease features of MPM, several strategies for local therapeutic delivery have been developed over the past years. The common rationale of these approaches is: (i) to reduce the risk of drug inactivation before reaching the target tumor cells; (ii) to increase the concentration of active drugs in the tumor micro-environment and their bioavailability; (iii) to reduce toxic effects on normal, non-transformed cells, because of much lower drug doses than those used for systemic chemotherapy. The complex interactions between drugs and the local immune-inflammatory micro-environment modulate the subsequent clinical response. In this perspective, the main interest is currently addressed to the development of local drug delivery platforms, both cell therapy and engineered nanotools. We here propose a review aimed at deep investigation of the biologic effects of the current local therapies for MPM, including cell therapies, and the mechanisms of interaction with the tumor micro-environment.

The effect of cisplatin-low-level laser therapy on cell viability and death of LNCaP prostate cancer cell line

Prostate cancer, as a common male cancer, is a serious threat to men's health. In spite of extreme developments for increasing survival rate, there are still limitations about common treatment options such as surgical procedures, radiotherapy, and chemotherapy. We hypothesized that combination of two treatments would bring better clinical outcomes. Therefore, the aim of this study was to determine the effect of conjugated cisplatin and low-level laser treatment (LLLT) on the viability of LNCaP prostate cancer cell line. LNCaP cells were harvested in DMEM containing 10% FBS and 1% antibiotic. Confluent cells were treated with different concentrations of cisplatin and different wavelengths of low-level laser (LLL) alone and in combination. The relative IC50 and cell viability was evaluated using MTT assay. Analysis of lipid peroxidation rate was performed using lipid peroxidation assay kit. LDH activity was also carried out on the treated and control cells using LDH cytotoxicity assay kit. Our results showed that combination of cisplatin and LLLT could effectively decrease cisplatin-induced cytotoxicity as well as LNCaP cell viability. Cisplatin-LLLT combination led to a significant increase in the MDA content as the product of membrane lipid peroxidation. Analyzing the LDH activity under the effect of cisplatin-LLL combined treatment showed a remarkable increase in the enzyme activity. We conclude that applying the cisplatin-LLL combination therapy is promising as an effective anti-cancer treatment. This novel combination has a potential to attenuate adverse side effects of earlier monotherapy strategies.

Integrative and Comprehensive Pancancer Analysis of Regulator of Chromatin Condensation 1 (RCC1)

Regulator of Chromatin Condensation 1 (RCC1) is the only known guanine nucleotide exchange factor that acts on the Ras-like G protein Ran and plays a key role in cell cycle regulation. Although there is growing evidence to support the relationship between RCC1 and cancer, detailed pancancer analyses have not yet been performed. In this genome database study, based on The Cancer Genome Atlas, Genotype-Tissue Expression and Gene Expression Omnibus databases, the potential role of RCC1 in 33 tumors' entities was explored. The results show that RCC1 is highly expressed in most human malignant neoplasms in contrast to healthy tissues. RCC1 expression is closely related to the prognosis of a broad variety of tumor patients. Enrichment analysis showed that some tumor-related pathways such as "cell cycle" and "RNA transport" were involved in the functional mechanism of RCC1. In particular, the conducted analysis reveals the relation of RCC1 to multiple immune checkpoint genes and suggests that the regulation of RCC1 is closely related to tumor infiltration of cancer-associated fibroblasts and CD8⁺ T cells. Coherent data demonstrate the association of RCC1 with the tumor mutation burden and microsatellite instability in various tumors. These findings provide new insights into the role of RCC1 in oncogenesis and tumor immunology in various tumors and indicate its potential as marker for therapy prognosis and targeted treatment strategies.

Perioperative Systemic Treatment for Muscle-Invasive Bladder Cancer: Current Evidence and Future Perspectives

Radical cystectomy is the primary treatment for muscle-invasive bladder cancer; however, approximately 50% of patients develop metastatic disease within 2 years of diagnosis, which results in dismal prognosis. Therefore, systemic treatment is important to improve the prognosis of muscle-invasive bladder cancer. Currently, several guidelines recommend cisplatin-based neoadjuvant chemotherapy before radical cystectomy, and adjuvant chemotherapy is recommended in patients who have not received neoadjuvant chemotherapy. Immune checkpoint inhibitors have recently become the standard treatment option for metastatic urothelial carcinoma. Owing to their clinical benefits, several immune checkpoint inhibitors, with or without other agents (including other immunotherapy, cytotoxic chemotherapy, and emerging agents such as antibody drug conjugates), are being extensively investigated in perioperative settings. Several studies for perioperative immunotherapy have shown that immune checkpoint inhibitors have promising efficacy with relatively low toxicity, and have explored the predictive molecular biomarkers. Herein, we review the current evidence and discuss the future perspectives of perioperative systemic treatment for muscle-invasive bladder cancer.

Systematic Analysis of the Oncogenic Role of WDR62 in Human Tumors

Background

Emerging studies support the oncogenic role of WD repeat domain 62 (WDR62) in few tumors, while no pan-cancer analysis is available. In this study, we analyzed systematically the oncogenic role of WDR62 across a series of human tumors based on bioinformatic data mining.

Methods

The expression level of WDR62 was analyzed via GEPIA2, TIMER, UALCAN, and StarBase databases. The prognostic role was analyzed via GEPIA2, TIMER, UALCAN, StarBase, TISIDB, TCGA portal, Kaplan-Meier Plotter, and PrognoScan databases. Then, we explored the causes for WDR62 abnormal expression via TCGA portal and UALCAN databases. Subsequently, the STRING and GeneMANIA databases were used to find the interactive networks for WDR62. Furthermore, we analyzed the correlation between WDR62 expression and immune features via TIMER and TISIDB databases.

Results

We found that WDR62 was significantly upregulated in most of the tumors and correlated with poor prognosis mainly in 6 candidate tumors—BLCA, BRCA, KIRC, KIRP, LIHC, and LUAD. Abnormal WDR62 expression may be probably attributed to TP53 mutation and promoter DNA methylation. Relative network analysis demonstrated that WDR62 was mainly involved in MAPK and toll-like receptor signaling pathway. WDR62 expression was associated with various immune cell infiltrations, especially cancer-associated fibroblasts (CAF) and T cell regulatory (Treg) cells, and was markedly correlated with poor prognosis. Moreover, WDR62 expression was closely associated with the expression of some immunomodulators such as PD-L1 and has a significant prognostic value.

Conclusions

Our study revealed that WDR62 could serve as a diagnostic and prognostic biomarker for several cancers. Importantly, WDR62 was closely associated with various immune cell infiltration, and to a certain extent, it can predict the effect of immunotherapy in particular PD1/PD-L1 inhibitors. Our pan-cancer study provided useful information on the oncogenic role of WDR62, contributing to further exploring the underlying mechanisms.

Astragalus membranaceus polysaccharides potentiate the growth-inhibitory activity of immune checkpoint inhibitors against pulmonary metastatic melanoma in mice

Astragalus membranaceus (A. membranaceus) is commonly used in various herbal formulations to treat several human and animal diseases. Polysaccharides, which are the major bioactive components in the A. membranaceus, exhibit various bioactive properties. However, the ability of A. membranaceus polysaccharides (APS) to activate the mucosal immune response has not been examined. We examined the effect of intranasal administration of APS on mucosal immune cell activation and the growth-inhibitory activity against pulmonary metastatic melanoma in mice by combination treatment with immune checkpoint blockade. The intranasal treatment of APS increased the number of lineage-CD11c+ dendritic cell (DCs) in the mesenteric lymph nodes (mLN) through the upregulation of CC-chemokine receptor 7 expression. Moreover, intranasal treatment of APS activated DCs, which further stimulated natural killer (NK) and T cells in the mLN. The APS/anti-PD-L1 antibody combination inhibited the pulmonary infiltration of B16 melanoma cells. The depletion of NK cells and CD8 T cells in mice mitigated the anti-cancer effect of this combination, thereby highlighting the critical role of NK cells and CD8 T cells in mediating anti-cancer immunity. These findings demonstrated that APS could be used as a topical mucosal adjuvant to enhance the immune check point inhibitor anti-cancer effect.

MicroRNA-326 attenuates immune escape and prevents metastasis in lung adenocarcinoma by targeting PD-L1 and B7-H3

Tumor-infiltrating T cells are highly expressive of inhibitory receptor/immune checkpoint molecules that bind to ligand expressed by tumor cells and antigen-presenting cells, and eventually lead to T cell dysfunction. It is a hot topic to restore T cell function by targeting immune checkpoint. In recent years, immunotherapy of blocking immune checkpoint and its receptor, such as PD-L1/PD-1 targeted therapy, has made effective progress, which brings hope for patients with advanced malignant tumor. However, only a few patients benefit from directly targeting these checkpoints or their receptors by small compounds or antibodies. Since the complexity of the regulation of immune checkpoints in tumor cells, further research is needed to identify the novel endogenous regulators of immune checkpoints which can help for developing effective drug target to improve the effect of immunotherapy. Here, we verified that microRNA-326 (miR-326) repressed the gene expression of immune checkpoint molecules PD-L1 and B7-H3 in lung adenocarcinoma (LUAD). We detected that the expression of miR-326 in LUAD tissue was negatively correlated with PD-L1/B7-H3. The repression of PD-L1 and B7-H3 expression through miR-326 overexpression leads to the modification the cytokine profile of CD8⁺ T cells and decreased migration capability of tumor cells. Meanwhile, the downregulation of miR-326 promoted tumor cell migration. Moreover, blocking PD-L1 and B7-H3 attenuated the tumor-promoting effect induced by miR-326 inhibitor. In tumor-bearing mice, the infiltration of CD8⁺ T cells was significantly increased and the expression of TNF-α, and IFN-γ was significantly enhanced which contributed to tumor progression after miR-326 overexpression. Collectively, miR-326 restrained tumor progression by downregulating PD-L1 and B7-H3 expression and increasing T cell cytotoxic function in LUAD. Our findings revealed a novel perspective on the complex regulation of immune checkpoint molecules. A new strategy of using miR-326 in tumor immunotherapy is proposed.

Two Complementarity Immunotherapeutics in Non-Small-Cell Lung Cancer Patients-Mechanism of Action and Future Concepts

Simple Summary

Here, we focused on the most important mechanisms of action of combined immunotherapy with modern anticancer approaches in patients with non-small-cell lung cancer. This knowledge is extremely important for lung cancer clinicians. First, it facilitates proper involvement of the patient in the treatment and monitoring its effectiveness. More importantly, the knowledge of the immunotherapy mechanisms will certainly allow quick recognition of the side effects of such a therapy, which are totally different of those observed after chemotherapy. Side effects of combination therapies can occur at any stage of treatment, and even after completion thereof. This review article could particularly explain the mechanism of action of combined immunotherapy, which have different targets in patients.

Abstract

Due to the limited effectiveness of immunotherapy used as first-line monotherapy in patients with non-small-cell lung cancer (NSCLC), the concepts of combining classical immunotherapy based on immune checkpoint antibodies with other treatment methods have been developed. Pembrolizumab and atezolizumab were registered in combination with chemotherapy for the treatment of metastatic NSCLC, while durvalumab found its application in consolidation therapy after successful chemoradiotherapy in patients with locally advanced NSCLC. Exceptionally attractive, due to their relatively low toxicity and high effectiveness, are treatment approaches in which a combination of two different immunotherapy methods is applied. This method is based on observations from clinical trials in which nivolumab and ipilimumab were used as first-line therapy for advanced NSCLC. It turned out that the dual blockade of immune checkpoints activated T lymphocytes in different compartments of the immune response, at the same time affecting the downregulation of immune suppressor cells (regulatory T cells). These experiments not only resulted in the registration of combination therapy with nivolumab and ipilimumab, but also initiated other clinical trials using immune checkpoint inhibitors (ICIs) in combination with other ICIs or activators of costimulatory molecules found on immune cells. There are also studies in which ICIs are associated with molecules that modify the tumour environment. This paper describes the mechanism of the synergistic effect of a combination of different immunotherapy methods in NSCLC patients.

Immune Checkpoint Inhibitor-Associated Pneumonitis in Non-Small Cell Lung Cancer: Current Understanding in Characteristics, Diagnosis, and Management

Immunotherapy that includes programmed cell death-1 (PD-1), programmed cell death- ligand 1 (PD-L1) and cytotoxic T lymphocyte antigen 4 (CTLA-4) inhibitors has revolutionized the therapeutic strategy in multiple malignancies. Although it has achieved significant breakthrough in advanced non-small cell lung cancer patients, immune-related adverse events (irAEs) including checkpoint inhibitor pneumonitis (CIP), are widely reported. As the particularly worrisome and potentially lethal form of irAEs, CIP should be attached more importance. Especially in non-small cell lung cancer (NSCLC) patients, the features of CIP may be more complicated on account of the overlapping respiratory signs compromised by primary tumor following immunotherapy. Herein, we included the previous relevant reports and comprehensively summarized the characteristics, diagnosis, and management of CIP. We also discussed the future direction of optimal steroid therapeutic schedule for patients with CIP in NSCLC based on the current evidence.

[MSI testing : What is new? What should be considered? German version]

Based on new trial data regarding immune checkpoint inhibitors (ICIs), the detection of high-grade microsatellite instability (MSI-H) or underlying deficient mismatch repair protein (dMMR) is now becoming increasingly important for predicting treatment response. For the first time, a PD‑1 ICI (pembrolizumab) has been approved by the European Medicines Agency (EMA) for first-line treatment of advanced (stage IV) dMMR/MSI‑H colorectal cancer (CRC). Further indications, such as dMMR/MSI‑H endometrial carcinoma (EC), have already succeeded (Dostarlimab, 2nd line treatment) and others are expected to follow before the end of 2021. The question of optimal testing in routine diagnostics should therefore be re-evaluated. Based on a consideration of the strengths and weaknesses of the widely available methods (immunohistochemistry and PCR), a test algorithm is proposed that allows quality assured, reliable, and cost-effective dMMR/MSI‑H testing. For CRC and EC, testing is therefore already possible at the primary diagnosis stage, in line with international recommendations (NICE, NCCN). The clinician is therefore enabled from the outset to consider not only the predictive but also the prognostic and predispositional implications of such a test when counseling patients and formulating treatment recommendations. As a basis for quality assurance, participation in interlaboratory comparisons and continuous documentation of results (e.g., QuIP Monitor) are strongly recommended.

Immune Monitoring in Melanoma and Urothelial Cancer Patients Treated with Anti-PD-1 Immunotherapy and SBRT Discloses Tumor Specific Immune Signatures

Simple Summary

Currently available biomarkers for response to checkpoint inhibitors are incomplete and predominantly focus on tumor tissue analysis e.g., tumor mutational burden, programmed cell death-ligand 1 (PD-L1) expression. Biomarkers in peripheral blood would allow a more dynamic monitoring and could offer a way for sequential adaptation of treatment strategy. We conducted an in-depth analysis of baseline and on-treatment systemic immune features in a cohort of stage III/IV melanoma and stage IV urothelial cancer (UC) patients treated with anti-programmed cell death-1 (anti-PD-1) therapy combined with stereotactic body radiotherapy (SBRT) in a similar regimen/schedule. Baseline immunity was clearly different between these two cohorts, indicating a less active immune landscape in UC patients. This study also detected signatures of proliferation in the CD8⁺ T-cell compartment pre-treatment and early after anti-PD-1 initiation that were positively correlated with clinical outcome in both tumor types. In addition our data support the biological relevance of PD-1/PD-L1 expression on circulating immune cell subsets, especially in melanoma.

Abstract

(1) Background: Blockade of the PD-1/PD-L1 pathway has revolutionized the oncology field in the last decade. However, the proportion of patients experiencing a durable response is still limited. In the current study, we performed an extensive immune monitoring in patients with stage III/IV melanoma and stage IV UC who received anti-PD-1 immunotherapy with SBRT. (2) Methods: In total 145 blood samples from 38 patients, collected at fixed time points before and during treatment, were phenotyped via high-parameter flow cytometry, luminex assay and UPLC-MS/MS. (3) Results: Baseline systemic immunity in melanoma and UC patients was different with a more prominent myeloid compartment and a higher neutrophil to lymphocyte ratio in UC. Proliferation (Ki67⁺) of CD8⁺ T-cells and of the PD-1⁺/PD-L1⁺ CD8⁺ subset at baseline correlated with progression free survival in melanoma. In contrast a higher frequency of PD-1/PD-L1 expressing non-proliferating (Ki67⁻) CD8⁺ and CD4⁺ T-cells before treatment was associated with worse outcome in melanoma. In UC, the expansion of Ki67⁺ CD8⁺ T-cells and of the PD-L1⁺ subset relative to tumor burden correlated with clinical outcome. (4) Conclusion: This study reveals a clearly different immune landscape in melanoma and UC at baseline, which may impact immunotherapy response. Signatures of proliferation in the CD8⁺ T-cell compartment prior to and early after anti-PD-1 initiation were positively correlated with clinical outcome in both cohorts. PD-1/PD-L1 expression on circulating immune cell subsets seems of clinical relevance in the melanoma cohort.

Immune checkpoints and cancer development: Therapeutic implications and future directions

Over the past few decades, different inhibitory receptors have been identified, which have played prominent roles in reducing anti-tumor immune responses. The role of immune checkpoint inhibitors in cancer was revealed by critical blockade of the cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) and programmed cell death protein-1 (PD-1) checkpoints. Immune checkpoint inhibitors, including anti-PD-1 (nivolumab and pembrolizumab), anti-PD-L1 (Atezolizumab, avelumab, and duravulumab), and anti-CTLA-4 (ipilimumab, tremelimumab), are currently FDA-approved treatment options for a broad range of cancer types. However, regarding immunotherapy advances in recent years, most studies have been focused on finding the antibodies against other inhibitory immune checkpoints in the tumor microenvironment such as lymphocyte activation gene-3 (LAG-3), T cell immunoglobulin, and mucin domain 3 (TIM-3), B7-homolog 3 (B7-H3), V-domain immunoglobulin-containing suppressor of T-cell activation (VISTA), diacylglycerol kinase-α (DGK-α), T cell immunoglobulin and ITIM domain (TIGIT), and B and T lymphocyte attenuator (BTLA). This immune checkpoint exerts differential inhibitory impacts on various types of lymphocytes. The suppression of immune responses demonstrates a surprising synergy with PD-1. Therefore, most antibodies against these immune checkpoints are undertaking clinical trials for cancer immunotherapy of advanced solid tumors and hematologic malignancies. In this review, we will summarize recent findings of immune checkpoint and the role of monoclonal antibodies in cancer immunotherapy targeting these receptors.

Alternative Splicing of Pre-mRNA in the Control of Immune Activity

The human immune response is a complex process that responds to numerous exogenous antigens in preventing infection by microorganisms, as well as to endogenous components in the surveillance of tumors and autoimmune diseases, and a great number of molecules are necessary to carry the functional complexity of immune activity. Alternative splicing of pre-mRNA plays an important role in immune cell development and regulation of immune activity through yielding diverse transcriptional isoforms to supplement the function of limited genes associated with the immune reaction. In addition, multiple factors have been identified as being involved in the control of alternative splicing at the cis, trans, or co-transcriptional level, and the aberrant splicing of RNA leads to the abnormal modulation of immune activity in infections, immune diseases, and tumors. In this review, we summarize the recent discoveries on the generation of immune-associated alternative splice variants, clinical disorders, and possible regulatory mechanisms. We also discuss the immune responses to the neoantigens produced by alternative splicing, and finally, we issue some alternative splicing and immunity correlated questions based on our knowledge.

AFP-Inhibiting Fragments for Drug Delivery: The Promise and Challenges of Targeting Therapeutics to Cancers

Alpha fetoprotein (AFP) plays a key role in stimulating the growth, metastasis and drug resistance of hepatocellular carcinoma (HCC). AFP is an important target molecule in the treatment of HCC. The application of AFP-derived peptides, AFP fragments and recombinant AFP (AFP-inhibiting fragments, AIFs) to inhibit the binding of AFP to intracellular proteins or its receptors is the basis of a new strategy for the treatment of HCC and other cancers. In addition, AIFs can be combined with drugs and delivery agents to target treatments to cancer. AIFs conjugated to anticancer drugs not only destroy cancer cells with these drugs but also activate immune cells to kill cancer cells. Furthermore, AIF delivery of drugs relieves immunosuppression and enhances chemotherapy effects. The synergism of immunotherapy and targeted chemotherapy is expected to play an important role in enhancing the treatment effect of patients with cancer. AIF delivery of drugs will be an available strategy for the targeted treatment of cancer in the future.

An inhibitor of programmed death ligand 1 enhances natural killer cell-mediated immunity against malignant melanoma cells

Since ionizing radiation has showed the dramatic effect to kill the cancer cells through direct DNA damage as well as triggering anti-cancer immune responses including induction of NKG2D ligands, it has used for long time to treat many cancer patients. However, it has been known that radiotherapy might promote the remnant cancer cells to escape immune system and metastasis. One of the suggested ways of immune evasion is induction of a ligand for programmed death-1 (PD-L1) in head and neck cancer, bladder cancer and lung cancer cells which engages the receptor, programmed death-1 (PD-1) in immune cells. PD-1/PD-L1 axis transduces the inhibitory signal and suppresses the adaptive immunity. However, their role in innate immunity remains poorly understood. Therefore, we investigated whether ionizing radiation could change the expression of PD-L1 in malignant melanoma cells and the receptor, programmed death-1 (PD-1), in NK-92 cells. Surface PD-L1 levels on melanoma cells were increased by ionizing radiation in a dose-independent manner but the level of PD-L1 was not changed significantly in NK-92 cells. Radiation-induced PD-L1 suppressed the activity of the NK-92 cells against melanoma cells despite of upregulation of NKG2D ligands. Furthermore, activated NK cells had high level of PD-1 and could not kill PD-L1+ melanoma cells effectively. When we used PD-L1 inhibitor or silenced PD-L1 gene, inhibited PD-1/PD-L1 axis reversed the activity of the suppressed NK cells. Through these results, we supposed that PD-1/PD-L1 blockade could enhance the immune responses of NK cells against melanoma cells after radiotherapy and might overcome the PD-L1 mediated radioresistance of cancer cells.

Targeting the PD-1/PD-L1 pathway in glioblastoma multiforme: Preclinical evidence and clinical interventions

Glioblastoma multiforme (GBM), as one of the immunosuppressive and common intrinsic brain tumors in adults, remains an intractable malignancy to manage. Since the standard of care for treatment, which includes surgery and chemoradiation, has not provided a sustainable and durable response in affected patients, seeking novel therapeutic approaches to treat GBM seems imperative. Immunotherapy, a breakthrough for cancer treatment, has become an attractive tool for combating cancer with the potential to access the blood-brain-barrier (BBB). In this regard, programmed cell death-1 (PD-1)/programmed cell death ligand-1 (PD-L1), as major immunological checkpoints, have drawn considerable interest due to their effectiveness in a spectrum of highly-aggressive neoplasms through negative regulation of the T-cell-mediated immune response. Nevertheless, due to the immunosuppressive microenvironment of GBM, the efficacy of these immune checkpoint inhibitors (ICIs), when used as monotherapy, has been unfavorable and lacks sufficient beneficial outcomes for GBM patients. A variety of clinical studies are attempting to evaluate the combination of ICIs (neoadjuvant/adjuvant) and existing treatment guidelines to strengthen their effectiveness; however, the exact mechanism of this signaling axis affects the consequences of immune therapy remains elusive. This review provides an overview of the PD-1/PD-L1 pathway, currently approved ICIs for clinical use, preclinical and clinical trials of PD-1/PD-L1 as monotherapy, and when used concomitantly with other GBM treatments.

Discovery of novel CA-4 analogs as dual inhibitors of tubulin polymerization and PD-1/PD-L1 interaction for cancer treatment

A series of novel CA-4 analogs as dual inhibitors of tubulin polymerization and PD-1/PD-L1 were designed, synthesized and bio-evaluated. Among them, compound TP5 exhibited strongest inhibitory effects against five cancer cell lines with an IC50 value of 800 nM in HepG2 cells. In addition, mechanism studies revealed that TP5 could effectively inhibit tubulin polymerization, suppress HepG2 cells migration and colony formation, and cause cell arrest at G2/M phase and induce apoptosis. Furthermore, TP5 exhibited moderate anti-PD-1/PD-L1 activity with IC50 values of 48.76 μM in a homogenous time-resolved fluorescence (HTRF) assay. In vivo efficacy studies indicated that TP5 could significantly suppress tumor growth in an immune checkpoint humanized mouse model with a Tumor Growth Suppression (TGI) of 57.9% at 100 mg/kg without causing significant toxicity. Moreover, TP5 did not cause in vivo cardiotoxicity in BALB/c mice. These results suggest that the novel CA-4 analogs may serve as a starting point for developing more potent dual inhibitors of tubulin polymerization and PD-1/PD-L1.

Soluble PD-L1 Is an Independent Prognostic Factor in Clear Cell Renal Cell Carcinoma

Simple Summary

Renal cell carcinoma (RCC) is a heterogeneous and complex disease with almost no response to chemotherapy. Immune checkpoint inhibitors have achieved great clinical success but no interesting circulating markers of clinical use have developed so far in clear cell renal cell carcinoma (CCRCC). We investigate the diagnostic and prognostic role of plasma PD-1 (sPD-1) and PD-L1 (sPD-L1) proteins for the first time together with the immunohistochemical expression counterpart of these proteins within the tumor front and tumor center in the same sample of patients with renal cancer undergoing surgery. We also investigate these plasma and tissue markers in the population of metastatic patients according to International mRCC Database Consortium (IMDC) prognostic groups and the response to systemic therapy. The independent role of sPD-L1 as a predictor of prognosis and treatment response is demonstrated.

Abstract

(1). Background: Immunohistochemical (IHC) evaluation of programmed death-1 (PD-1) and its ligand (PD-L1) is being used to evaluate advanced malignancies with potential response to immune checkpoint inhibitors. We evaluated both plasma and tissue expression of PD-1 and PD-L1 in the same cohort of patients, including non-metastatic and metastatic clear cell renal cell carcinoma (CCRCC). Concomitant plasma and tissue expression of PD-1 and PD-L1 was evaluated with emphasis on diagnostic and prognostic implications. (2) Methods: we analyzed PD-1 and PD-L1 IHC expression in tumor tissues and soluble forms (sPD-1 and sPD-L1) in plasma from 89 patients with CCRCC, of which 23 were metastatic and 16 received systemic therapy. The primary endpoint was evaluation of overall survival using Kaplan-Meier analysis and the Cox regression model. Plasma samples from healthy volunteers were also evaluated. (3) Results: Interestingly, sPD-1 and sPD-L1 levels were lower in cancer patients than in controls. sPD-1 and sPD-L1 levels and their counterpart tissue expression both at the tumor center and infiltrating front were not associated. Higher expression of both PD-1 and PD-L1 were associated with tumor grade, necrosis and tumor size. PD-1 was associated to tumor stage (pT) and PD-L1 to metastases. sPD-1 and sPD-L1 were not associated with clinico-pathological parameters, although both were higher in patients with synchronous metastases compared to metachronous ones and sPD-L1 was also higher for metastatic patients compared to non-metastatic patients. sPD-1 was also associated with the International Metastatic Renal Cell Cancer Database Consortium (IMDC) prognostic groups in metastatic CCRCC and also to the Morphology, Attenuation, Size and Structure (MASS) response criteria in metastatic patients treated with systemic therapy, mainly tyrosine-kinase inhibitors. Regarding prognosis, PD-L1 immunostaining at the tumor center with and without the tumor front was associated with worse survival, and so was sPD-L1 at a cut-off >793 ng/mL. Combination of positivity at both the tissue and plasma level increased the level of significance to predict prognosis. (4) Conclusions: Our findings corroborate the role of PD-L1 IHC to evaluate prognosis in CCRCC and present novel data on the usefulness of plasma sPD-L1 as a promising biomarker of survival in this neoplasia.

Recent advance of peptide-based molecules and nonpeptidic small-molecules modulating PD-1/PD-L1 protein-protein interaction or targeting PD-L1 protein degradation

Tumor immunotherapy has made great progress in recent years. In the tumor microenvironment, the binding of PD-1 and its ligand PD-L1 can promote tumor immune escape and tumor survival. Clinical studies have indicated that antibodies blocking PD-1 and PD-L1 have reliable effects on many advanced malignant tumors. However, no small-molecule inhibitors have been approved so far, indicating that the development of marketable small-molecules PD-1/PD-L1 targeted therapy drugs is a challenging process. Small-molecule inhibitors can overcome the limitations of monoclonal antibodies, including poor oral bioavailability, high cost, poor tissue and tumor penetration and long half-life, which prompt researchers to turn their attention to the development of peptide molecules and small-molecule inhibitors modulating PD-1/PD-L1 to overcome some disadvantages of monoclonal antibodies or targeting PD-L1 protein degradation as potential alternatives or supplements. In this review, we will focus on the peptide-based and nonpeptidic molecules against PD-1/PD-L1 base on the structural classification. More importantly, we also focus on the latest research progress of small-molecules mediated PD-L1 degradation mechanism.

Safety and efficacy of cetuximab-containing chemotherapy after immune checkpoint inhibitors for patients with squamous cell carcinoma of the head and neck: a single-center retrospective study

Immunotherapy has been shown to prolong survival in recurrent or metastatic squamous cell carcinoma of the head and neck (SCCHN) in front-line use; however, subsequent systemic therapy has not been optimized. This study aimed to evaluate the safety and efficacy of cetuximab-containing chemotherapy after immunotherapy. We retrospectively analyzed patients with recurrent or metastatic SCCHN who underwent cetuximab-containing regimens after progression on immunotherapy. Of the 22 patients who met the inclusion criteria, 21 received paclitaxel and cetuximab, and 1 carboplatin and fluorouracil and cetuximab after immunotherapy. Nine patients achieved a partial response, 10 patients had stable disease as their best response on cetuximab-containing chemotherapy, yielding an overall response rate and disease control rate of 40.9 and 86.4%, respectively. The median progression-free survival was 5.2 months, and the median overall survival was 14.5 months. Ten patients developed grade 3-4 adverse events, including neutropenia (31.8%), acneiform rash (9.1%), anemia (4.5%), hypertransaminasemia (4.5%) and stomatitis (4.5%). The most frequent cetuximab-related toxicities across all grades were skin reactions (77.3%), hypomagnesemia (40.9%), stomatitis (27.3%), paronychia (13.6%) and keratitis (4.5%). There was no treatment-related death. Taken together, cetuximab-containing chemotherapy was effective and feasible even after immunotherapy.

Efficacy and safety of anti-PD-1/anti-PD-L1 antibody therapy in treatment of advanced gastric cancer or gastroesophageal junction cancer: A meta-analysis

BACKGROUND

Faced with limited and inadequate treatment options for patients with advanced gastric cancer or gastroesophageal junction cancer (GC/GEJC), researchers have turned toward, with the support of promising clinical trials, anti-PD-1/anti-PD-L1 antibody therapy. But there are also different clinical trial results. To better assess its efficacy and safety, we integrated data from 13 eligible studies for a systematic review and meta-analysis.

AIM

To comprehensively evaluate the efficacy and safety of anti-PD-1/anti-PD-L1 antibody therapy in the treatment of advanced GC/GEJC patients.

METHODS

PubMed, Web of Science, Cochrane Library ,and EMBASE databases were searched to identify eligible articles with outcomes including objective response rate (ORR), disease control rate (DCR), overall survival (OS), progression-free survival (PFS), and adverse events (AEs) of anti-PD-1/anti-PD-L1 antibody therapy.

RESULTS

Our study encompassed a total of 13 trials totaling 1618 patients. The outcomes showed a pooled ORR and DCR of 15% (95% confidence interval [CI]: 14%-18%) and 40% (95%CI: 33%-46%), respectively. The pooled 6-mo OS and PFS were 54% (95%CI: 45%-64%) and 26% (95%CI: 20%-32%), respectively, and the 12-mo OS and PFS were 42% (95%CI: 21%-62%) and 11% (95%CI: 8%-13%), respectively. In addition, the incidence of any-grade AEs and grade ≥ 3 AEs was 64% (95%CI: 54%-73%) and 18% (95%CI: 16%-20%), respectively. Most importantly, PD-L1 positive patients exhibited a higher ORR rate than PD-L1 negative patients (odds ratio = 2.54, 95%CI: 1.56-4.15).

CONCLUSION

Anti-PD-1/anti-PD-L1 antibody therapy has shown promising anti-tumor efficacy with manageable AEs in advanced GC/GEJC patients, with PD-L1 overexpressing patients exhibiting a higher ORR. What is more, the clinical efficacy of anti-PD-1/PD-L1 combined with traditional chemotherapy drugs is even better, although the occurrence of AEs still causes considerate concerns.

CDK12/13 inhibition induces immunogenic cell death and enhances anti-PD-1 anticancer activity in breast cancer

Immunogenic cell death (ICD) improves the T cell response against different tumors, indicating that ICD can enhance the antitumor immunity elicited by the anti-checkpoint antibody anti-programmed death 1 (anti-PD-1). In the present study, we reported a synergistic and durable immune-mediated antitumor response elicited by the combined treatment of SR-4835, a CDK12/13 specific inhibitor, with PD-1 blockade in a syngeneic mouse model. The developed combination therapy elicited antitumor activity in immunocompetent mouse tumor models. Furthermore, the SR-4835-treated tumor cells exhibited characteristics of ICD, including the release of high mobility group box 1 (HMGB1) and ATP and calreticulin (CRT) translocation. This activity led to a significant T-cell-dependent tumor suppression. The enhanced dendritic cell (DC) and infiltration of T cells activation in the tumors treated with both SR-4835 and anti-PD-1 indicate that this combination treatment promotes an improved immune response. Therefore, the results of the present study demonstrate the potential of CDK12/13 inhibition combined with checkpoint inhibition in breast cancer treatment.

The efficacy and safety of combined immune checkpoint inhibitors (nivolumab plus ipilimumab): a systematic review and meta-analysis

BACKGROUND

Currently, nivolumab and ipilimumab are the most widely used immune checkpoint inhibitors. We performed a meta-analysis to evaluate the efficacy and treatment-related adverse events (TRAEs) of nivolumab plus ipilimumab therapy in cancer treatment.

METHODS

We examined data from PubMed, Web of Science, EBSCO, and Cochrane Library. Eleven articles fulfilled our criteria, which we divided into 3 groups: nivolumab plus ipilimumab versus nivolumab (the dose used for monotherapy is 3 mg/kg), nivolumab plus ipilimumab versus ipilimumab (the dose used for monotherapy is 3 mg/kg), and nivolumab 1 mg/kg plus ipilimumab 3 mg/kg (N1I3) versus nivolumab 3 mg/kg plus ipilimumab 1 mg/kg (N3I1). We measured the complete response (CR), partial response (PR), objective response rate (ORR), and TRAEs in any grade and grade 3 or higher.

RESULTS

The overall effect estimate favored the combined immunotherapy group in terms of the ORR (RR: 1.40, p < 0.001) and PR (RR: 1.50, p < 0.001) than nivolumab alone. Compared with ipilimumab alone, the combined immunotherapy group had better CR (RR: 4.89, p < 0.001), PR (RR: 2.75, p < 0.001), and ORR (RR: 3.31, p < 0.001). Finally, N1I3 showed better PR (RR: 1.35, p = 0.006) and ORR (RR: 1.21, p = 0.03) than N3I1. The incidence of any TRAEs was similar between both groups (RR: 1.05, p = 0.06). However, the incidence of serious adverse events (grade 3 or higher) was lower in group N3I1 than group N1I3 (RR: 1.51, p < 0.001).

CONCLUSION

This meta-analysis showed that the curative effect of nivolumab plus ipilimumab was better than that of nivolumab or ipilimumab monotherapy. In the combined immunotherapy group, N1I3 was more effective than N3I1. Although the side effects were slightly increased in N1I3 group, overall safety was acceptable.

Opportunities for Conventional and in Situ Cancer Vaccine Strategies and Combination with Immunotherapy for Gastrointestinal Cancers, A Review

Survival of gastrointestinal cancer remains dismal, especially for metastasized disease. For various cancers, especially melanoma and lung cancer, immunotherapy has been proven to confer survival benefits, but results for gastrointestinal cancer have been disappointing. Hence, there is substantial interest in exploring the usefulness of adaptive immune system education with respect to anti-cancer responses though vaccination. Encouragingly, even fairly non-specific approaches to vaccination and immune system stimulation, involving for instance influenza vaccines, have shown promising results, eliciting hopes that selection of specific antigens for vaccination may prove useful for at least a subset of gastrointestinal cancers. It is widely recognized that immune recognition and initiation of responses are hampered by a lack of T cell help, or by suppressive cancer-associated factors. In this review we will discuss the hurdles that limit efficacy of conventional cancer therapeutic vaccination methods (e.g., peptide vaccines, dendritic cell vaccination). In addition, we will outline other forms of treatment (e.g., radiotherapy, chemotherapy, oncolytic viruses) that also cause the release of antigens through immunogenic tumor cell death and can thus be considered unconventional vaccination methods (i.e., in situ vaccination). Finally, we focus on the potential additive value that vaccination strategies may have for improving the effect immunotherapy. Overall, a picture will emerge that although the field has made substantial progress, successful immunotherapy through the combination with cancer antigen vaccination, including that for gastrointestinal cancers, is still in its infancy, prompting further intensification of the research effort in this respect.

Radiomics study for predicting the expression of PD-L1 in non-small cell lung cancer based on CT images and clinicopathologic features

PURPOSE

To predict programmed death-ligand 1 (PD-L1) expression of tumor cells in non-small cell lung cancer (NSCLC) patients by using a radiomics study based on CT images and clinicopathologic features.

MATERIALS AND METHODS

A total of 390 confirmed NSCLC patients who performed chest CT scan and immunohistochemistry (IHC) examination of PD-L1 of lung tumors with clinic data were collected in this retrospective study, which were divided into two cohorts namely, training (n = 260) and validation (n = 130) cohort. Clinicopathologic features were compared between two cohorts. Lung tumors were segmented by using ITK-snap kit on CT images. Total 200 radiomic features in the segmented images were calculated using in-house texture analysis software, then filtered and minimized by least absolute shrinkage and selection operator (LASSO) regression to select optimal radiomic features based on its relevance of PD-L1 expression status in IHC results and develop radiomics signature. Radiomics signature and clinicopathologic risk factors were incorporated to develop prediction model by using multivariable logistic regression analysis. The receiver operating characteristic (ROC) curves were generated and the areas under the curves (AUC) were reckoned to predict PD-L1 expression in both training and validation cohorts.

RESULTS

In 200 extracted radiomic features, 9 were selected to develop radiomics signature. In univariate analysis, PD-L1 expression of lung tumors was significantly correlated with radiomics signature, histologic type, and histologic grade (p < 0.05, respectively). However, PD-L1 expression was not correlated with gender, age, tumor location, CEA level, TNM stage, and smoking (p > 0.05). For prediction of PD-L1 expression, the prediction model that combines radiomics signature and clinicopathologic features resulted in AUCs of 0.829 and 0.848 in the training and validation cohort, respectively.

CONCLUSION

The prediction model that incorporates the radiomics signature and clinical risk factors has potential to facilitate the individualized prediction of PD-L1 expression in NSCLC patients and identify patients who can benefit from anti-PD-L1 immunotherapy.