Xiaobo He

Upregulation of PD-L1 by EGFR activation mediates the immune escape in EGFR-driven NSCLC: Implication for optional immune targeted therapy for NSCLC patients with EGFR mutation

Introduction: Epidermal growth factor receptor (EGFR) mutation status was reported to be associated with programmed death-ligand 1 (PD-L1) expression. However, the molecular mechanism of PD-L1 regulation by EGFR activation and the potential clinical significance of blocking PD-1/PD-L1 in EGFR-mutant non–small-cell lung cancer (NSCLC) treated with EGFR tyrosine kinase inhibitors (TKIs) were largely unknown. Methods: Western blot, real-time polymerase chain reaction, immunofluorescence, and flow cytometry were employed to explore the association between PD-L1 and EGFR activation. Then, we used EGFR-TKIs and downstream pathways inhibitors to clarify the detailed signaling pathway involved in PD-L1 regulation. Cell apoptosis, viability, and enzyme-linked immunosorbent assay test were used to study the immune suppression by EGFR activation and immune reactivation by EGFR-TKIs and/or PD-1 blocking in tumor cells and human peripheral blood mononuclear cells coculture system. Results: We found that EGFR activation by EGF stimulation, exon-19 deletions, and L858R mutation could induce PD-L1 expression. EGFR activation upregulated PD-L1 through p-ERK1/2/p-c-Jun but not through p-AKT/p-S6 pathway. PD-L1 mediated by EGFR activation could induce the apoptosis of T cells through PD-L1/PD-1 axis in tumor cells and peripheral blood mononuclear cells coculture system. Inhibiting EGFR by EGFR-TKIs could free the inhibition of T cells and enhance the production of interferon-&ggr;. Synergistic tumor cell killing effects were not observed with EGFR-TKIs and anti-PD-1 antibody combination treatment in coculture system. Conclusions: Our results imply that EGFR-TKIs could not only directly inhibit tumor cell viability but also indirectly enhance antitumor immunity through the downregulation of PD-L1. Anti-PD-1/PD-L1 antibodies could be an optional therapy for EGFR-TKI sensitive patients, especially for EGFR-TKIs resistant NSCLC patients with EGFR mutation. Combination of EGFR-TKIs and anti-PD-1/PD-L1 antibodies treatment in NSCLC is not supported by the current study but warrant more studies to move into clinical practice.

Ratio of C-Reactive Protein/Albumin is An Inflammatory Prognostic Score for Predicting Overall Survival of Patients with Small-cell Lung Cancer

Recent studies have indicated that the C-reactive protein/ albumin (CRP/Alb) ratio is associated with clinical outcomes in patients with hepatocellular carcinoma (HCC). We examined the prognostic value of this ratio in patients with small-cell lung cancer (SCLC). In this retrospective study, a total of 367 eligible SCLC patients were analyzed and the correlation between the pretreatment CRP/Alb ratio and overall survival (OS) was investigated. The optimal cutoff level of CRP/Alb ratio was at 0.441. A low and high CRP/Alb ratio was assigned to 65.1% and 34.9% of patients, respectively. The median OS of patients with a high CRP/Alb ratio was worse than those in the low group (13.70 vs 18.90 months HR, 1.34; p = 0.005). Disease stage (p < 0.001), performance status (PS) (p < 0.001) and pretreatment LDH (p < 0.001) were also significant predictors of OS. Multivariate analyses showed that the CRP/Alb ratio is an independent prognostic factor (p = 0.025). This study demonstrated that the CRP/Alb ratio could independently predict OS in patients with SCLC, and had comparable prognostic value to other known prognostic markers. Therefore, the CRP/Alb ratio could have prognostic value and be a measurable biomarker in patients with SCLC.

Upregulation of PD-L1 by EML4-ALK fusion protein mediates the immune escape in ALK positive NSCLC: Implication for optional anti-PD-1/PD-L1 immune therapy for ALK-TKIs sensitive and resistant NSCLC patients

ABSTRACT Driver mutations were reported to upregulate programmed death-ligand 1 (PD-L1) expression. However, how PD-L1 expression and immune function was affected by ALK-TKIs and anti-PD-1/PD-L1 treatment in ALK positive non-small-cell lung cancer (NSCLC) remains poorly understood. In the present study, western-blot, real-time PCR, flow cytometry and immunofluorescence were employed to explore how PD-L1 was regulated by ALK fusion protein. ALK-TKIs and relevant inhibitors were used to identify the downstream signaling pathways involved in PD-L1 regulation. Cell apoptosis, viability and Elisa test were used to study the immune suppression by ALK activation and immune reactivation by ALK-TKIs and/or PD-1 blocking in tumor cells and DC-CIK cells co-culture system. We found that PD-L1 expression was associated with EGFR mutations and ALK fusion genes in NSCLC cell lines. Over-expression of ALK fusion protein increased PD-L1 expression. PD-L1 mediated by ALK fusion protein increased the apoptosis of T cells in tumor cells and DC-CIK cells co-culture system. Inhibiting ALK by sensitive TKIs could enhance the production of IFNγ. Anti-PD-1 antibody was effective in both crizotinib sensitive and resistant NSCLC cells. Synergistic tumor killing effects were not observed with ALK-TKIs and anti-PD-1 antibody combination in co-culture system. ALK-TKIs not only directly inhibited tumor viability but also indirectly enhanced the antitumor immunity via the downregulation of PD-L1. Anti-PD-1/PD-L1 antibodies could be an optional therapy for crizotinib sensitive, especially crizotinib resistant NSCLC patients with ALK fusion gene. Combination of ALK-TKIs and anti-PD-1/PD-L1 antibodies treatment for ALK positive NSCLC warrants more data before moving into clinical practice.

PD-L1 is remarkably over-expressed in EBV-associated pulmonary lymphoepithelioma-like carcinoma and related to poor disease-free survival

Backgroud Programmed cell death-ligand 1 (PD-L1) and driver mutations are commonly seen in non-small-cell lung cancer (NSCLC). However, the prevelance of PD-L1 over-expression and its prognostic value in Epstein–Barr virus (EBV) associated pulmonary lymphoepithelioma-like carcinoma (LELC) remains poorly understood. Methods A total of 214 NSCLC patients and 113 surgically treated pulmonary LELC patients were included. Paraffin-embedded tumor sections were stained with PD-L1 antibody. Correlations between PD-L1 expression and clinicopathological features as well as survival outcomes were analyzed. Results The frequency of PD-L1 over-expression in NSCLC was 51.4%. No significant association was observed between common driver mutations and PD-L1 over-expression. Remakably, the positive rate of PD-L1 in pulmonary LELC was 74.3%. High PD-L1 expression was associated with impaired diseas-free survival (DFS) compared with low PD-L1 expression (p = 0.008). Multivariate analysis shows that PD-L1 expression level, N stage and M stage were independent prognostic factors for DFS. N stage and M stage but not PD-L1 expression level were significantly associated with overall survival (OS). Conclusions PD-L1 over-expression was not related to common driver mutations in NSCLC. Pulmonary LELC have remarkably high incidence of PD-L1 expression. PD-L1 was a negative prognostic factor for DFS in surgically resected pulmonary LELC. These findings may provide a rationale for immunotarget therapy in this virus-associated lung cancer.

Pretreatment Albumin/Globulin Ratio Predicts the Prognosis for Small-Cell Lung Cancer.

AbstractThe pretreatment albumin/globulin ratio (AGR) has been used as a prognostic factor in various cancers. This study aimed to evaluate the predictive value of AGR in small-cell lung cancer (SCLC).We tested albumin and total proteins in plasma samples from 276 SCLC patients from our cancer center between January 2003 and December 2006. The AGR was defined by the formula: albumin/(total proteins–albumin). The correlation between AGR and overall survival (OS) was examined by Kaplan–Meier and Cox regression methods. For validation, AGR was used to evaluate the prognosis of SCLC in another independent group.Total 276 patients (testing) and 379 patients (validation) were finally enrolled. The median OS was 15.31 months for testing patients and 15.06 months for validation patients, respectively. We determined 1.29 as the cutoff value by using the biostatistical tool (Cutoff Finder), then the patients in the testing group were classified into 2 groups. Kaplan–Meier curves showed high AGR group had significantly longer OS than low AGR group (P = 0.026). According to multivariate analyses, AGR was an independent prognostic factor for OS of SCLC patients in the testing group (HR, 1.35, 95% CI: 1.01–1.81, P = 0.046). In the validation group, AGR was also verified as a predictive factor for OS (P < 0.001), and the risk of SCLC in the low AGR group was 1.43 times higher than that in the high AGR group (HR, 1.43, 95% CI: 1.05–1.94, P = 0.022).AGR is an independent prognostic marker in SCLC patients. Furthermore, it could be of great value in the management of SCLC patients.

Expression and significance of Cystatin-C in clear cell renal cell carcinoma

PURPOSE Cystatin-C (Cys-C) has been studied as a valuable prognostic indicator in several malignancies. The goal of this study is to explore the expression and prognostic significance of Cys-C in clear cell renal cell carcinoma (CCRCC). METHODS Immunohistochemistry and western blot assays were performed to evaluate the level of Cys-C expression in CCRCC tissue. Expression levels of Cys-C in CCRCC tissue samples in relation to clinicopathological characteristics of the tumors were assessed. Their prognostic significance was analyzed by univariate and multivariate analyses. In addition, the expression of Cys-C in 786-O cell lines was inhibited by using CRISPR/Case9 and the effects of Cys-C knockout on 786-O cells in vitro were evaluated using MTT method, colony formation assay, cell cycle assay, and cell migration and invasive assay. RESULTS The expression level of Cys-C was lower in CCRCC tissues (n = 253) than in paired adjacent non-cancerous tissues (n = 164) by immunohistochemistry (P < 0.001). Among the 253 patients, the results showed that patients with low Cys-C expression level in cancer tissue has longer overall survival (OS) than that with high Cys-C level. Furthermore, knockout of Cys-C in 786-O cell line has ability to suppress cell proliferation, induce G0/G1 phase arrest, inhibited cell invasion, decreased phosphorylation of ERK1/2, STAT-3 and enhanced phosphorylated JNK expression. CONCLUSIONS A decrease in serum Cys-C is a favorable prognostic indicator for CCRCC patients. Inhibition of Cys-C suppressed RCC 786-O cell proliferation and invasion. These results indicated that Cys-C could serve as an ideal prognostic biomarker in patients with CCRCC.

The expression of plakoglobin is a potential prognostic biomarker for patients with surgically resected lung adenocarcinoma

Purpose This study aimed to explore the relationship between plakoglobin expression and clinical data in the patients with surgically resected lung adenocarcinoma. Results With follow-up of median 50.14 months, the average PFS and OS were 16.82 and 57.92 months, respectively. In 147 patients, recurrence or death was observed in 131 patients. According to the log-rank test, low plakoglobin expression was a significant predictor for favorable DFS (P=0.006) and OS (P=0.043). For the analyses within subgroups, high plakoglobin expression was an independent factor for reducing DFS in non-metastatic patients with resected lung adenocarcinoma (P < 0.05). Moreover, high plakoglobin expression was associated with poor DFS even receiving adjuvant chemotherapy (P =0.028) and with a shorter DFS (HR, 2.01, 95%CIs, 1.35 to 2.97, P=0.001) and OS (HR, 1.94, 95%CIs, 1.12 to 3.37, P=0.019). Patients and methods The expression of plakoglobin in 147 primary tumor tissues was examined by using immunohistochemistry and clinical data were collected. The optimal cutoff value of immunoreactivity score (IRS) was calculated and used to divide all the patients into two groups: low-level group (IRS: 0-3, n=59) and high-level group (IRS: 4-12, n=88). Kaplan–Meier curves were applied to assess the plakoglobin expression and clinical variables. The univariate and multivariate Cox model analyses were performed to evaluate the effects of clinical factors and plakoglobin expression on disease-free survival (DFS) and overall survival (OS). Conclusion High plakoglobin expression is an independent negative prognostic factor for patients with surgically resected lung adenocarcinoma.

Optimal tumor shrinkage predicts long-term outcome in advanced nonsmall cell lung cancer (NSCLC) treated with target therapy: Result from 3 clinical trials of advanced NSCLC by 1 institution

Abstract Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are used as standard therapies for advanced nonsmall cell lung cancer (NSCLC) patients with EGFR mutation positive. Because these targeted therapies could cause tumor necrosis and shrinkage, the purpose of the study is to search for a value of optimal tumor shrinkage as an appropriate indicator of outcome for advanced NSCLC. A total of 88 NSCLC enrollees of 3 clinical trials (IRESSA registration clinical trial, TRUST study and ZD6474 study), who received Gefitinib (250 mg, QD), Erlotinib (150 mg, QD), and ZD6474 (100 mg, QD), respectively, during December 2003 and October 2007, were retrospectively analyzed. The response evaluation criteria in solid tumors (RECIST) were used to identify responders, who had complete response (CR) or partial responses (PR) and nonresponders who had stable disease (SD) or progressive disease (PD). Receiver operating characteristics (ROC) analysis was used to find the optimal tumor shrinkage as an indicator for tumor therapeutic outcome. Univariate and multivariate Cox regression analyses were performed to compare the progression-free survival (PFS) and overall survival (OS) between responders and nonresponders stratified based on radiologic criteria. Among the 88 NSCLC patients, 26 were responders and 62 were nonresponders based on RECIST 1.0. ROC indicated that 8.32% tumor diameter shrinkage in the sum of the longest tumor diameter (SLD) was the cutoff point of tumor shrinkage outcomes, resulting in 46 responders (⩽8.32%) and 42 nonresponders (≥8.32%). Univariate and multivariate Cox regression analyses indicated that (1) the responders (⩽8.32%) and nonresponders (≥ −8.32%) were significantly different in median PFS (13.40 vs 1.17 months, P < 0.001) and OS (19.80 vs 7.90 months, P < 0.001) and (2) –8.32% in SLD could be used as the optimal threshold for PFS (hazard ratio [HR], 8.11, 95% CI, 3.75 to 17.51, P < 0.001) and OS (HR, 2.36, 95% CI, 1.41 to 3.96, P = 0.001). However, 8.32% tumor diameter shrinkage is validated as a reliable outcome predictor of advanced NSCLC patients receiving EGFR-TKIs therapies and may provide a practical measure to guide therapeutic decisions.