A systematic review and meta-analysis of PD-1/PD-L1 inhibitors in specific patient subgroups with advanced gastro-oesophageal junction and gastric adenocarcinoma

Immune checkpoint inhibitors in gastrointestinal malignancies: an Umbrella review

In the Modern era, immune checkpoint inhibitors (ICIs) have been the cornerstone of success in the treatment of several malignancies. Despite remarkable therapeutic advances, complex matrix together with significant molecular and immunological differences have led to conflicting outcomes of ICI therapy in gastrointestinal (GI) cancers. As far we are aware, to date, there has been no study to confirm the robustness of existing data, and this study is the first umbrella review to provide a more comprehensive picture about ICIs' efficacy and safety in GI malignancies. Systematic search on PubMed, Scopus, Web of Science, EMBASE, and Cochrane library identified 14 meta-analyses. The pooled analysis revealed that ICIs application, especially programmed death-1 (PD-1) inhibitors such as Camrelizumab and Sintilimab, could partially improve response rates in patients with GI cancers compared to conventional therapies. However, different GI cancer types did not experience the same efficacy; it seems that hepatocellular carcinoma (HCC) and esophageal cancer (EC) patients are likely better candidates for ICI therapy than GC and CRC patients. Furthermore, application of ICIs in a combined-modal strategy are perceived opportunity in GI cancers. We also assessed the correlation of PD-L1 expression as well as microsatellite status with the extent of the response to ICIs; overall, high expression of PD-L1 in GI cancers is associated with better response to ICIs, however, additional studies are required to precisely elaborate ICI responses with respect to microsatellite status in different GI tumors. Despite encouraging ICI efficacy in some GI cancers, a greater number of serious and fatal adverse events have been observed; further highlighting the fact that ICI therapy in GI cancers is not without cost, and further studies are required to utmost optimization of this approach in GI cancers.

Hepatocellular carcinoma immune prognosis score predicts the clinical outcomes of hepatocellular carcinoma patients receiving immune checkpoint inhibitors

OBJECTIVE

The predictive biomarkers of immune checkpoint inhibitors (ICIs) in hepatocellular carcinoma (HCC) still need to be further explored. This study aims to establish a new immune prognosis biomarker to predict the clinical outcomes of hepatocellular carcinoma patients receiving immune checkpoint inhibitors.

METHODS

The subjects of this study were 151 HCC patients receiving ICIs at Harbin Medical University Cancer Hospital from January 2018 to December 2021. This study collected a wide range of blood parameters from patients before treatment and used Cox's regression analysis to identify independent prognostic factors in blood parameters, as well as their β coefficient. The hepatocellular carcinoma immune prognosis score (HCIPS) was established through Lasso regression analysis and COX multivariate analysis. The cut-off value of HCIPS was calculated from the receiver operating characteristic (ROC) curve. Finally, the prognostic value of HCIPS was validated through survival analysis, stratified analyses, and nomograms.

RESULTS

HCIPS was composed of albumin (ALB) and thrombin time (TT), with a cut-off value of 0.64. There were 56 patients with HCIPS < 0.64 and 95 patients with HCIPS ≥ 0.64, patients with low HCIPS were significantly related to shorter progression-free survival (PFS) (13.10 months vs. 1.63 months, P < 0.001) and overall survival (OS) (14.83 months vs. 25.43 months, P < 0.001). HCIPS has also been found to be an independent prognostic factor in this study. In addition, the stratified analysis found a significant correlation between low HCIPS and shorter OS in patients with tumor size ≥ 5 cm (P of interaction = 0.032). The C-index and 95% CI of the nomograms for PFS and OS were 0.730 (0.680-0.779) and 0.758 (0.711-0.804), respectively.

CONCLUSIONS

As a new score established based on HCC patients receiving ICIs, HCIPS was significantly correlated with clinical outcomes in patients with ICIs and might serve as a new biomarker to predict HCC patients who cloud benefit from ICIs.

Clinical significance of CD155 expression and correlation with cellular components of tumor microenvironment in gastric adenocarcinoma

Introduction

CD155 is recently emerging as a promising target in malignancies. However, the relationship between CD155 expression and tumor microenvironment (TME) cell infiltration in gastric adenocarcinoma (GAC) has rarely been clarified.

Methods

We measured CD155 expression in specimens of gastric precancerous disease and GAC by immunohistochemistry. The association of CD155 expression with GAC progression and cells infiltration in TME was evaluated through 268 GAC tissues and public dataset analysis.

Results

We showed that the expression of CD155 was positively correlated with the pathological development of gastric precancerous disease (r = 0.521, P < 0.0001). GAC patients with high CD155 expression had a poorer overall survival (P = 0.033). Moreover, CD155 expression correlated with aggressive clinicopathological features including tumor volume, tumor stage, lymph node involvement, and cell proliferation (P <0.05). Remarkably, CD155 expression positively related to the infiltration of CD68+ macrophages in TME (P = 0.011). Meanwhile, the positive correlation was observed between CD155 and CD31 (P = 0.026). In addition, patients with high CD155 expression combined with low CD3, CD4, CD8, IL-17, IFN-γ or CD19 expression as well as those with high CD155 and α-SMA expression showed significantly worse overall survival (P < 0.05).

Conclusions

CD155 may play a pivotal role in the development of GAC through both immunological and non-immunological mechanisms and be expected to become a novel target of immunotherapy in GAC patients.

Efficacy of PD-1/PD-L1 inhibitors in advanced gastroesophageal cancer based on characteristics: a meta-analysis

Objective: Evaluate the potency of anti-PD-1/PD-L1 antibodies in advanced gastroesophageal cancer patients with different clinical features. Methods: Randomized, controlled trials comparing anti-PD-1/PD-L1 antibodies with chemotherapy in individuals with gastroesophageal cancer were retrieved. Results: 15 trials involving 9194 individuals were included. PD-1/PD-L1 inhibitors significantly improved overall survival (OS) but not progression-free survival. Significantly improved OS was observed in PD-L1 combined positive score ≥1, primary esophageal cancer, primary gastric cancer and Asian patients. Subgroup analysis revealed significant OS benefit achieved for esophageal squamous cell carcinoma, but not for esophageal adenocarcinoma. Conclusion: PD-1/PD-L1 inhibitors improved OS in advanced gastroesophageal carcinoma, especially in patients with esophageal cancer. Race, primary tumor sites and PD-L1 combined positive score can be used to predict the potency of immune checkpoint inhibitors.

Genomic landscape of virus-associated cancers

It has been estimated that 15%-20% of human cancers are attributable to infections, mostly by carcinogenic viruses. The incidence varies worldwide, with a majority affecting developing countries. Here, we present a comparative analysis of virus-positive and virus-negative tumors in nine cancers linked to five viruses. We find that virus-positive tumors occur more frequently in males and show geographical disparities in incidence. Genomic analysis of 1,658 tumors reveals virus-positive tumors exhibit distinct mutation signatures and driver gene mutations and possess a lower somatic mutation burden compared to virus-negative tumors of the same cancer type. For example, compared to the respective virus-negative counterparts, virus-positive cases across different cancer histologies had less often mutations of TP53 and deletions of 9p21.3/ CDKN2 A- CDKN1A ; Epstein-Barr virus-positive (EBV+) gastric cancer had more frequent mutations of EIF4A1 and ARID1A and less marked mismatch repair deficiency signatures; and EBV-positive cHL had fewer somatic genetic lesions of JAK-STAT, NF-κB, PI3K-AKT and HLA-I genes and a less pronounced activity of the aberrant somatic hypermutation signature. In cHL, we also identify germline homozygosity in HLA class I as a potential risk factor for the development of EBV-positive Hodgkin lymphoma. Finally, an analysis of clinical trials of PD-(L)1 inhibitors in four virus-associated cancers suggested an association of viral infection with higher response rate in patients receiving such treatments, which was particularly evident in gastric cancer and head and neck squamous cell carcinoma. These results illustrate the epidemiological, genetic, prognostic, and therapeutic trends across virus-associated malignancies.

Prognostic nutritional index for predicting the clinical outcomes of patients with gastric cancer who received immune checkpoint inhibitors

OBJECTIVE

Although the application of immunotherapy in gastric cancer has achieved satisfactory clinical effects, many patients have no response. The aim of this retrospective study is to investigate the predictive ability of the prognostic nutrition index (PNI) to the prognosis of patients with gastric cancer who received immune checkpoint inhibitors (ICIs).

MATERIALS AND METHODS

Participants were 146 gastric cancer patients with ICIs (PD-1/PD-L1 inhibitors) or chemotherapy. All patients were divided into a low PNI group and a high PNI group based on the cut-off evaluated by the receiver operating characteristic (ROC) curve. We contrasted the difference in progression-free survival (PFS) and overall survival (OS) in two groups while calculating the prognosis factors for PFS and OS by univariate and multivariate analyses. Moreover, the nomogram based on the results of the multivariate analysis was constructed to estimate the 1- and 3-year survival probabilities.

RESULTS

There were 41 (28.1%) cases in the low PNI group and 105 (71.9%) cases in the high PNI group. The median survival time for PFS in the low PNI group and high PNI group was 12.30 months vs. 33.07 months, and 18.57 months vs. not reached in the two groups for OS. Patients in low PNI group were associated with shorter PFS and OS in all patients [Hazard ratio (HR) = 1.913, p = 0.013 and HR = 2.332, p = 0.001]. Additionally, in subgroup analysis, low PNI group cases also had poorer PFS and OS, especially in patients with ICIs. In addition, the multivariate analysis found that carbohydrate antigen 724 (CA724) and TNM stage were independent prognostic factors for PFS. At the same time, indirect bilirubin (IDBIL), CA724, PNI, and TNM stage were independent prognostic factors for OS.

CONCLUSION

Prognostic nutrition index was an accurate inflammatory and nutritional marker, which could predict the prognosis of patients with gastric cancer who received ICIs. PNI could be used as a biomarker for ICIs to identify patients with gastric cancer who might be sensitive to ICIs.

Efficacy of PD-1/PD-L1 inhibitors in patients with advanced gastroesophageal cancer: An updated meta-analysis based on randomized controlled trials

Background: This study aimed to investigate the clinical efficacy of programmed death-1 receptor and ligand-1 (PD-1/PD-L1) inhibitors in gastroesophageal cancer patients and the relationship between their clinicopathological features and curative treatment effects.

Methods: A systematic search was conducted for articles published before April 2022 from online databases (PubMed, EMBASE, Web of Science and the Cochrane Library). The main outcome was overall survival (OS).

Results: This meta-analysis comprised 16 studies involving 9,304 participants. The results indicated that compared with chemotherapy, patients treated with PD-1/PD-L1 inhibitors had significantly improved OS (HR = 0.80; p < 0.001) but no significant improvement in progression-free survival (PFS) (p = 0.185). Subgroup analyses demonstrated that PD-1/PD-L1 inhibitors combined with chemotherapy, esophageal squamous cell carcinoma, male, Asian patients and combined positive score (CPS) ≥1 were significantly associated with better survival outcomes. Further, subgroup analysis of gender revealed that the OS of all subgroups containing male patients was significantly improved compared with chemotherapy, unlike that of female patients. In addition, the line of therapy, Lauren classification, age and eastern cooperative oncology group (ECOG) performance status were not associated with PD-1/PD-L1 inhibitors efficacy.

Conclusion: The results indicated that PD-1/PD-L1 inhibitors could prolong the OS of advanced gastroesophageal cancer patients. Clinicopathological features such as therapeutic schedules, tumor types, histological type, gender, geographical region and PD-L1 expression status (CPS) seemed to be associated with survival outcomes.

Effects of H2O2 Treatment Combined With PI3K Inhibitor and MEK Inhibitor in AGS Cells: Oxidative Stress Outcomes in a Model of Gastric Cancer

Gastric cancer is worldwide the fifth and third cancer for incidence and mortality, respectively. Stomach wall is daily exposed to oxidative stress and BER system has a key role in the defense from oxidation-induced DNA damage, whilst ErbB receptors have important roles in the pathogenesis of cancer. We used AGS cells as an aggressive gastric carcinoma cell model, treated with H₂O₂ alone or combined with ErbB signaling pathway inhibitors, to evaluate the effects of oxidative stress in gastric cancer, focusing on the modulation of ErbB signaling pathways and their eventual cross-talk with BER system. We showed that treatment with H₂O₂ combined with PI3K/AKT and MEK inhibitors influenced cell morphology and resulted in a reduction of cancer cell viability. Migration ability was reduced after H₂O₂ treatment alone or combined with MEK inhibitor and after PI3K/AKT inhibitor alone. Western blotting analysis showed that oxidative stress stimulated EGFR pathway favoring the MAPKs activation at the expense of PI3K/AKT pathway. Gene expression analysis by RT-qPCR showed ErbB2 and OGG1 increase under oxidative stress conditions. Therefore, we suggest that in AGS cells a pro-oxidant treatment can reduce gastric cancer cell growth and migration via a different modulation of PI3K and MAPKs pathways. Moreover, the observed ErbB2 and OGG1 induction is a cellular response to protect the cells from H₂O₂-induced cell death. In conclusion, to tailor specific combinations of therapies and to decide which strategy to use, administration of a chemotherapy that increases intracellular ROS to toxic levels, might not only be dependent on the tumor type, but also on the molecular targeting therapy used.

Neoadjuvant/Perioperative Treatment Affects Spatial Distribution and Densities of Tumor Associated Neutrophils and CD8+ Lymphocytes in Gastric Cancer

Tumor associated neutrophils (TANs) and cytotoxic T cells (CTLs) are part of the tumor microenvironment of gastric cancer (GC). We explored their tumor biological significance in neoadjuvantly/perioperatively treated GC. Immunostaining was performed on whole tissue sections of 173 GCs, using antibodies directed against myeloperoxidase (MPO) and CD8. Stained specimens were digitalized, and the densities of TANs and CTLs were assessed separately in the mucosa, tumor surface, tumor center, invasion front, and tumor scar. The densities were correlated with clinicopathological patient characteristics. Compared with a historical cohort of 449 treatment naive GCs, the TAN density in the invasion front was significantly lower in neoadjuvantly/perioperatively treated GCs. TAN density in the tumor center and invasion front correlated with tumor regression. TAN density also correlated with CTL density in the tumor center and invasion front. A high density of CTL in the tumor center correlated with an improved overall survival and tumor specific survival. We show that neoadjuvant/perioperative (radio-) chemotherapy impacts on the immune microenvironment of GC, while also depending on sex. The density of TANs in neoadjuvantly/perioperatively treated GCs differed from findings made in a treatment naive GC cohort.

Comparison of PD-1 Inhibitors in Patients With Advanced Esophageal Squamous Cell Carcinoma in the Second-Line Setting

Background

KEYNOTE-181, ATTRACTION-3, and ESCORT trials have opened the era of programmed death 1 (PD-1) inhibitors in the second-line therapy for esophageal squamous cell carcinoma (ESCC). There is no head-to-head comparison of pembrolizumab vs. nivolumab vs. camrelizumab in the second-line setting for ESCC. We performed an indirect comparison to explore the optimal choice of immune checkpoint inhibitor (ICI) for advanced ESCC.

Methods

Patients in ATTRACTION-3 and ESCORT were all squamous carcinoma, while KEYNOTE-181 enrolled both adenocarcinoma and squamous carcinoma patients. We only extract information of patients with squamous carcinoma from KEYNOTE 181 study and all the patients from ATTRACTION-3 and ESCORT. The main clinical outcomes for this study were overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and treatment-related adverse events (TRAEs).

Results

Indirect analysis showed similar survival benefit among three PD-1 inhibitors. Nivolumab was comparable with pembrolizumab in most subgroups except that nivolumab was slightly better for patients with performance status (PS) score of 1 [HRnivo/pembro: 0.68 (95% confidence interval (CI): 0.45–1.02], p = 0.07). Compared with nivolumab indirectly, pembrolizumab and camrelizumab had better PFS [HRpembro/nivo: 0.85 (95% CI: 0.63–1.14), p = 0.29; HRcam/nivo: 0.64 (95% CI: 0.47–0.87), p = 0.004] and significantly higher ORR [RRpembro/nivo: 2.51 (95% CI: 1.22–5.15), p = 0.01; RRcam/nivo: 3.52 (95% CI: 1.73–7.18), p = 0.001]. Compared with camrelizumab indirectly, pembrolizumab had slightly worse PFS [HRpembro/cam: 1.33 (95% CI: 0.99–1.79), p = 0.057] and comparable ORR [RRpembro/cam: 0.71 (95% CI: 0.32–1.60; p = 0.41)]. Camrelizumab had a significantly higher rate of all grade TRAEs than both pembrolizumab and nivolumab.

Conclusions

Combining the safety and potential survival benefit, we recommend nivolumab for ESCC patients with PS score of 1 and pembrolizumab or camrelizumab for patients with better PS and seeking for higher efficacy or longer PFS.