Consistency comparison of programmed cell death 1-ligand 1 in different immuno-histochemical staining methods / 北京大学学报(医学版)

OBJECTIVE@#To compare the consistency of programmed cell death 1-ligand 1 (PD-L1, clone E1L3N, 22C3, SP263) in different immunohistochemical staining methods.@*METHODS@#The first step was to select the optimal process: The PD-L1(clone E1L3N) antibody recommended process, self-built process ①, self-built process ② and self-built process ③ were used to perform immunohistochemical staining in 5 cases of tonsil tissue. The quality of all slides was scored by expert pathologists (0-6 points). The process with the highest score was selected. The second step was to compare the consistency between the optimal procedure and the two standard procedures. Thirty-two cases of lung non-small cell carcinoma diagnosed by pathology in Peking University First Hospital in the past two years were randomly selected. The 32 cases were stained in parallel with the SP263 and 22C3 standard procedures, and all stained slides were scored by specialized pathologists for tumor proportion score (TPS). The scoring results were grouped according to < 1%, ≥1% to < 10%, ≥10% to < 50%, and ≥50%. The consistency of PD-L1 detection antibody clone E1L3N and 22C3, E1L3N and SP263 staining results was analyzed.@*RESULTS@#Tonsil stained slides scores (0-6 points) were as follows: The recommended protocol was 5, 5, 5, 5 and 5. The self-built process ① was 5, 6, 6, 5 and 6. The self-built process ② was 4, 4, 4, 4 and 4.The self-built process ③ was 3, 3, 3, 3 and 3. The self-built process ① was the best with the highest score. The TPSs of 32 non small cell lung carcinoma (NSCLC) cases were as follows: Of self-built process ①, 6 cases were lower than 1%, 5 cases were from 1% to 10%, 10 cases were from 10% to 50%, and 11 cases were higher than 50%; of 22C3 standard procedure, 5 cases were lower than 1%, 3 cases were from 1% to 10%, 13 cases were from 10% to 50%, 11 cases were higher than 50%; of SP263 standard procedure, 7 cases were lower than 1%, 4 cases were from 1% to 10%, 11 cases were from 10% to 50%, 10 cases were higher than 50%. The results of the consistency test were as follows: The κ value for self-built process ① and 22C3 standard procedure was 0.736 (P < 0.001), the agreement was good; the κ value for self-built process ① and SP263 standard procedure was 0.914 (P < 0.001), the agreement was very good.@*CONCLUSION@#The immunostaining using PD-L1(E1L3N) with validated self-built staining protocol ① by Ventana Benchmark GX platform can obtain high quality of slides, and the TPSs based on these slides are in good agreement with 22C3 and SP263 standard procedures.

Clinicopathological features and prognosis of SMARCA4-deficient non-small cell lung carcinoma: an analysis of 127 cases / 中华病理学杂志

Objective: To investigate and elucidate the clinicopathological and prognostic characteristics of SMARCA4-deficient non-small cell lung cancer. Methods: The clinicopathological and prognostic data were collected in 127 patients with SMARCA4-deficient non-small cell lung cancer diagnosed in Shanghai Pulmonary Hospital, Shanghai, China from January 2020 to March 2022. The variation and expression of biomarkers related to treatment were retrospectively reviewed. Results: One hundred and twenty-seven patients were eligible for enrollment. Among them 120 patients (94.5%) were male and 7 cases (5.5%) were female, while the average age was 63 years (range 42-80 years). There were 41 cases (32.3%) of stage Ⅰ cancer, 23 cases (18.1%) of stage Ⅱ, 31 cases (24.4%) of stage Ⅲ and 32 cases (25.2%) of stage Ⅳ. SMARCA4 expression detected by immunohistochemistry was completely absent in 117 cases (92.1%) and partially absent in 10 cases (7.9%). PD-L1 immunohistochemical analyses were performed on 107 cases. PD-L1 was negative, weakly positive and strongly positive in 49.5% (53/107), 26.2% (28/107) and 24.3% (26/107) of the cases, respectively. Twenty-one cases showed gene alterations (21/104, 20.2%). The KRAS gene alternation (n=10) was most common. Mutant-type SMARCA4-deficient non-small cell lung cancer was more commonly detected in females, and was associated with positive lymph nodes and advanced clinical stage (P<0.01). Univariate survival analysis showed that advanced clinical stage was a poor prognosis factor, and vascular invasion was a poor predictor of progression-free survival in patients with surgical resection. Conclusions: SMARCA4-deficient non-small cell lung cancer is a rare tumor with poor prognosis, and often occurs in elderly male patients. However, SMARCA4-deficient non-small cell lung cancers with gene mutations are often seen in female patients. Vascular invasion is a prognostic factor for disease progression or recurrence in patients with resectable tumor. Early detection and access to treatment are important for improving patient survivals.

Effect of MiR-424-5p on the Drug Resistance of Diffuse Large B-Cell Lymphoma Cells by Regulating PD-1/PD-L1 Signaling Pathway / 中国实验血液学杂志

OBJECTIVE@#To explore the effect of microRNA-424-5p (miR-424-5p) on the drug resistance of diffuse large B-cell lymphoma (DLBCL) cells by regulating the programmed death receptor-1 (PD-1)/programmed death ligand-1 (PD-L1) signaling pathway.@*METHODS@#Human DLBCL cell line CRL2631 cells were induced to construct CRL2631-CHOP resistant cell line. RT-qPCR and Western blot were used to detect the expression levels of MiR-424-5p, PD-L1 mRNA and protein, and multidrug resistance gene-1 (MDR-1) protein in CRL2631 cells and CRL2631-CHOP cells, respectively. The target genes of MiR-424-5p was verified by dual luciferase reporter assay. The miRNA simulation/interference technology and thiazole blue (MTT) method were used to detect the resistance of CRL2631 cells and CRL2631-CHOP cells to CHOP.@*RESULTS@#Compared with CRL2631 cells, the drug resistance of CRL2631-CHOP cells to CHOP and the levels of MDR-1 protein (P<0.05), PD-L1 mRNA and protein in the cells were significantly increased (both P<0.001), while the relative level of MiR-424-5p was significantly reduced (P<0.001). The result of the dual luciferase reporter assay showed that PD-L1 was the direct downstream target gene of MiR-424-5p (P<0.001). After transfection of MiR-424-5p inhibitor, the resistance of CRL2631 cells to CHOP drugs increased, and the expression level of MDR-1 protein (P<0.01), PD-L1 mRNA and protein also increased significantly (both P<0.01). After transfection of MiR-424-5p mimics, the resistance of CRL2631-CHOP cells to CHOP drugs decreased, and the expression level of MDR-1 protein (P<0.001), PD-L1 mRNA and protein also decreased significantly (both P<0.001). Overexpression of PD-L1 could reverse the inhibitory effect of upregulating MiR-424-5p on PD-L1 (P<0.001).@*CONCLUSION@#Down-regulation of MiR-424-5p enhances the drug resistance of DLBCL cells by regulating the PD-1/PD-L1 signaling pathway.

Pathological features and immune microenvironment in HER-2 intratumoral heterogeneous breast cancers / 中华肿瘤杂志

Objective: To observe the clinical pathology features, and immune microenvironment of HER-2 intratumoral heterogeneity breast cancer. Methods: Thirty cases of HER-2 intratumoral heterogeneous breast cancer were retrospectively analyzed in Tianjin Medical University Cancer Institute and Hospital from November 2017 to June 2020. HER-2 expression was detected by immunohistochemistry and verified by dual color silver-enhanced in-situ hybridization (D-SISH). HER-2 intratumoral positive and negative regions were divided. The pathological characteristics, subtype, and the level of tumor infiltrating lymphocytes (TILs) and the expression of programmed cell death-ligand 1 (PD-L1) were evaluated respectively. Results: The proportion of HER-2 positive cells of the breast cancer ranged from 10% to 90%. The pathological type was mainly invasive non-special typecarcinoma. Six cases presented different pathological types between HER-2 positive and negative regions. The HER-2-positive areas included 2 cases of carcinoma with apocrine differentiation, and the negative areas included 2 cases of invasive micropapillary carcinoma, 1 case of invasive papillary carcinoma, and 1 case of carcinoma with apocrine differentiation. In HER-2 positive regions, 17 cases were Luminal B and 13 cases were HER-2 overexpressed types. There were 22 cases of Luminal B and 8 cases of triple negative tumors in the HER-2 negative areas. The levels of TILs in HER-2 positive and negative areas accounted for 53.3% (16/30) and 26.7% (8/30), respectively, with a statistically significant difference (P=0.035). The positive expression of PD-L1 in HER-2 positive area and HER-2 negative area were 6 cases and 9 cases, respectively. Among 8 cases with HER-2 negative regions containing triple negative components, 4 cases were positive for PD-L1 expression. Conclusions: In the case of HER-2 intratumoral heterogeneity, it is necessary to pay attention to both HER-2 positive and negative regions, and evaluate subtype separately as far as possible. For HER-2 intratumoral heterogeneous breast cancer containing triple negative components, the treatment mode can be optimized by refining the intratumoral expression of PD-L1.

The expression and function of PD-L1 in CD133(+) human liver cancer stem-like cells / 中华肿瘤杂志

Objective: To investigate the expression of programmed death protein-ligand 1 (PD-L1) in liver cancer stem-like cells (LCSLC) and its effect on the characteristics of tumor stem cells and tumor biological function, to explore the upstream signaling pathway regulating PD-L1 expression in LCSLC and the downstream molecular mechanism of PD-L1 regulating stem cell characteristics, also tumor biological functions. Methods: HepG2 was cultured by sphere-formating method to obtain LCSLC. The expressions of CD133 and other stemness markers were detected by flow cytometry, western blot and real-time quantitative polymerase chain reaction (RT-qPCR) were used to detect the expressions of stemness markers and PD-L1. The biological functions of the LCSLC were tested by cell function assays, to confirm that the LCSLC has the characteristics of tumor stem cells. LCSLC was treated with cell signaling pathway inhibitors to identify relevant upstream signaling pathways mediating PD-L1 expression changes. The expression of PD-L1 in LCSLC was down regulated by small interfering RNA (siRNA), the expression of stem cell markers, tumor biological functions of LCSLC, and the changes of cell signaling pathways were detected. Results: Compared with HepG2 cells, the expression rate of CD133 in LCSLC was upregulated [(92.78±6.91)% and (1.40±1.77)%, P<0.001], the expressions of CD133, Nanog, Oct4A and Snail in LCSLC were also higher than those in HepG2 cells (P<0.05), the number of sphere-formating cells increased on day 7 [(395.30±54.05) and (124.70±19.30), P=0.001], cell migration rate increased [(35.41±6.78)% and (10.89±4.34)%, P=0.006], the number of transmembrane cells increased [(75.77±10.85) and (20.00±7.94), P=0.002], the number of cloned cells increased [(120.00±29.51) and (62.67±16.77), P=0.043]. Cell cycle experiments showed that LCSLC had significantly more cells in the G(0)/G(1) phase than those in HepG2 [(54.89±3.27) and (32.36±1.50), P<0.001]. The tumor formation experiment of mice showed that the weight of transplanted tumor in LCSLC group was (1.32±0.17)g, the volume is (1 779.0±200.2) mm(3), were higher than those of HepG2 cell [(0.31±0.06)g and (645.6±154.9)mm(3), P<0.001]. The expression level of PD-L1 protein in LCSLC was 1.88±0.52 and mRNA expression level was 2.53±0.62, both of which were higher than those of HepG2 cells (P<0.05). The expression levels of phosphorylation signal transduction and transcription activation factor 3 (p-STAT3) and p-Akt in LCSLC were higher than those in HepG2 cells (P<0.05). After the expression of p-STAT3 and p-Akt was down-regulated by inhibitor treatment, the expression of PD-L1 was also down-regulated (P<0.05). In contrast, the expression level of phosphorylated extracellular signal-regulated protein kinase 1/2 (p-ERK1/2) in LCSLC was lower than that in HepG2 cells (P<0.01), there was no significant change in PD-L1 expression after down-regulated by inhibitor treatment (P>0.05). After the expression of PD-L1 was knockdown by siRNA, the expressions of CD133, Nanog, Oct4A and Snail in LCSLC were decreased compared with those of siRNA-negative control (NC) group (P<0.05). The number of sphere-formating cells decreased [(45.33±12.01) and (282.00±29.21), P<0.001], the cell migration rate was lower than that in siRNA-NC group [(20.86±2.74)% and (46.73±15.43)%, P=0.046], the number of transmembrane cells decreased [(39.67±1.53) and (102.70±11.59), P=0.001], the number of cloned cells decreased [(57.67±14.57) and (120.70±15.04), P=0.007], the number of cells in G(0)/G(1) phase decreased [(37.68±2.51) and (57.27±0.92), P<0.001], the number of cells in S phase was more than that in siRNA-NC group [(30.78±0.52) and (15.52±0.83), P<0.001]. Tumor formation in mice showed that the tumor weight of shRNA-PD-L1 group was (0.47±0.12)g, the volume is (761.3±221.4)mm(3), were lower than those of shRNA-NC group [(1.57±0.45)g and (1 829.0±218.3)mm(3), P<0.001]. Meanwhile, the expression levels of p-STAT3 and p-Akt in siRNA-PD-L1 group were decreased (P<0.05), while the expression levels of p-ERK1/2 and β-catenin did not change significantly (P>0.05). Conclusion: Elevated PD-L1 expression in CD133(+) LCSLC is crucial to maintain stemness and promotes the tumor biological function of LCSLC.

Expert consensus on PD-L1 expression testing in esophageal carcinoma in China / 中华肿瘤杂志

In recent years, immunotherapy represented by immune checkpoint inhibitors programmed death 1 (PD-1) has made great progress in the treatment of esophageal cancer and is rewriting the global paradigm for the treatment of esophageal cancer. According to current data, only a small number of patients with esophageal cancer could benefit from immunotherapy. Therefore, it is a challenge to screen the potential beneficiaries of PD-1 inhibitors. Studies have shown that the expression level of programmed death-ligand 1 (PD-L1) in esophageal cancer is closely associated with the efficacy of PD-1 inhibitors, and PD-L1 is the most important predictive biomarker of the efficacy of PD-1 inhibitors. With the clinical application of different PD-1 inhibitors and PD-L1 protein expression detection platforms, clarifying the clinical significance and timing of detection of PD-L1 protein expression in esophageal cancer, and establishing a standardized PD-L1 testing procedure, are of great significance to improve the accuracy of detection and reduce the difference between laboratories, so as to maximize the therapeutic benefits for patients. This consensus was finally reached, based on the combination of literature, expert experience, and internal discussion and voting of committee members, to provide an accurate and reliable evidence for clinicians to make decisions.

Pathological features related to onco-immunity and their clinical significance of pancreatic ductal adenocarcinoma / 中华病理学杂志

Objective: To investigate the tumor immunity-related pathologic features and clinical significance in pancreatic ductal adenocarcinoma (PDAC). Methods: All pathologic materials and clinical information of 192 PDAC patients from the Cancer Hospital of the University of Chinese Academy of Sciences from January 2010 to December 2020 were collected. The onco-immune microenvironment associated morphologic features were evaluated, and MHC-Ⅰ, PD-L1, CD3, and CD8 expression were detected by immunohistochemistry (IHC). Then the correlation between the factors and their influence on prognosis was analyzed. Results: There were 163 cases of non-specific adenocarcinoma (163/192, 84.90%), 18 cases of adeno-squamous carcinoma (18/192, 9.37%), and 11 cases of other rare subtypes (11/192, 5.73%). Perineural invasion was observed in 110 cases (110/192, 57.29%) and vascular invasion in 86 cases (86/192, 44.79%). There were 84 cases (84/182, 46.15%) with severe chronic inflammation. Tumor infiltrating immune cell numbers (TII-N) were increased in 52 cases (52/192, 27.08%). Lymphocytes and plasma cells were the main infiltrating immune cells in 60 cases (60/192, 31.25%), whereas in 34 cases (34/192, 17.71%) the tumors were mainly infiltrated by granulocytes, and 98 cases (98/192, 51.04%) showed mixed infiltration. CD3+T cells were deficient in 124 cases (124/192, 66.31%). CD8+T cells were deficient in 152 cases (152/192, 79.58%). MHC-Ⅰ expression was down-regulated in 156 cases (156/192, 81.25%), and PD-L1 was positive (CPS≥1) in 46 cases (46/192, 23.96%). Statistical analysis showed that TII-N was negatively correlated with vascular invasion (P=0.035), perineural invasion (P=0.002), stage (P=0.004) and long-term alcohol consumption (P=0.039). The type of immune cells correlated positively with chronic pancreatic inflammation (P=0.002), and negatively with tumor differentiation (P=0.024). CD8+T cells were positively correlated with CD3+T cells (P=0.032), MHC-Ⅰ expression (P<0.001) and PD-L1 expression (P=0.001), and negatively correlated with long-term smoking (P=0.016). Univariate analysis showed that histological nonspecific type (P=0.013) and TII-N (P<0.001) were the factors for good prognosis. Vascular invasion (P=0.032), perineural invasion (P=0.001), high stage (P=0.003) and long-term alcohol consumption (P=0.004) were adverse prognostic factors. COX multivariate risk analysis found that TII-N was an independent favorable factor for PDAC, while perineural invasion was an independent adverse risk factor. Conclusions: TII-N is an independent superior prognostic factor for PDAC, and significantly correlated with many factors; chronic alcohol consumption and smoking may inhibit onco-immunity in PDAC patients.

Real-world study on the efficacy and prognostic predictive biomarker of patients with metastatic non-small cell lung cancer treated with programmed death-1/programmed death ligand 1 inhibitors / 中华肿瘤杂志

Objective: To describe the actual efficacy of programmed death-1 (PD-1)/ programmed-death ligand 1 (PD-L1) inhibitors in patients with metastatic non-small cell lung cancer (NSCLC) and explore potential prognostic predictive biomarkers. Methods: Patients with metastatic NSCLC who were treated with PD-1/PD-L1 inhibitors at Cancer Hospital, Chinese Academy of Medical Sciences from January 2016 to December 2019, either as monotherapy or in combination with other agents, were consecutively enrolled into this study. We retrospectively collected the data of demographics, clinical information and pathologic assessment to evaluate the therapeutic efficacy and conduct the survival analysis. Major endpoint of our study is progression-free survival (PFS). Secondary endpoints include objective response rate (ORR), disease control rate (DCR) and overall survival (OS). Results: The ORR of 174 patients who underwent PD-1/PD-L1 inhibitor was 28.7%, and the DCR was 79.3%. Immune-related adverse events (irAEs) occurred in 23 patients (13.2%). Brain metastasis, line of treatment, and treatment patterns were associated with the ORR of metastatic NSCLC patients who underwent immunotherapy (P<0.05). After a median follow-up duration of 18.8 months, the median PFS was 10.5 months (ranged from 1.5 to 40.8 months) while the median OS was not reached. The 2-year survival rate was estimated to be 63.0%. The pathologic type was related with the PFS of metastatic NSCLC patients who underwent immunotherapy (P=0.028). Sex, age, brain metastasis and autoimmune diseases were associated with OS (P<0.05). Analysis of the receptor characteristic curve (ROC) of neutrophil/lymphocyte ratio (NLR) predicting ORR of immunotherapy in metastatic NSCLC showed that the areas under the curve of NLR before immunotherapy (NLR(C0)), NLR after one cycle of immunotherapy (NLR(C1)) and ΔNLR were 0.600, 0.706 and 0.628, respectively. Multivariate logistic regression analysis showed that NLR(C1) was an independent factor of the ORR of metastatic NSCLC patients who underwent immunotherapy (OR=0.161, 95% CI: 0.062-0.422), and the efficacy of combination therapy was better than that of single agent (OR=0.395, 95% CI: 0.174-0.896). The immunotherapy efficacy in patients without brain metastasis was better than those with metastasis (OR=0.291, 95% CI: 0.095-0.887). Multivariate Cox regression analysis showed that NLR(C1) was an independent influencing factor of PFS of metastatic NSCLC patients after immunotherapy (HR=0.480, 95% CI: 0.303-0.759). Sex (HR=0.399, 95% CI: 0.161-0.991, P=0.048), age (HR=0.356, 95% CI: 0.170-0.745, P=0.006) were independent influencing factors of OS of metastatic NSCLC patients after immunotherapy. Conclusions: PD-1/PD-L1 inhibitors are proved to be efficacious and have tolerable toxicities for patients with metastatic NSCLC. Patients at advanced age could still benefit from immunotherapy. Brain metastasis is related to compromised response. Earlier application of immunotherapy in combination with other modalities enhances the efficacy without elevating risk of irAEs. NLR(C1) is an early predictor of clinical outcome. The OS of patients younger than 75 years may be improved when treated with immunotherapy.

The IL-6/STAT3 signaling pathway mediated by radiotherapy regulates the expression of PD-L1 in esophageal cancer cells / 中华肿瘤杂志

Objective: To explore the possible mechanism of radiotherapy regulating the expression of PD-L1 in esophageal carcinoma. Methods: Three esophageal cancer cell lines (Eca109, Kyse150, TE1) were irradiated with different doses of X-rays, and 6 Gy+ AG490 group was set. The mRNA expression of PD-L1 was detected by real-time quantitative polymerase chain reaction (RT-qPCR). The protein expressions of PD-L1, STAT3, p-STAT3 were detected by western blotting and the protein level of IL-6 was detected by ELISA. Results: The mRNA expressions of PD-L1 in Eca109, Kyse150 and TE1 were 2.86±0.30, 960.01±21.27 and 106.78±6.67, higher than 1.07±0.15 in normal esophageal cell line HET-1A (P<0.01). The protein expressions of PD-L1 in Eca109, Kyse150 and TE1 were 0.091±0.036, 1.533±0.079 and 0.914±0.035, higher than 0.063±0.01 in normal esophageal cell line HET-1A (P<0.01). After 48 hours of 6 Gy irradiation, the protein expression levels of PD-L1 in Eca109, Kyse150 and TE1 were 0.135±0.007, 1.66±0.06 and 1.32±0.06, higher than 0.09±0.01, 1.21±0.05 and 0.93±0.03 of the 0 Gy group (P<0.01), while the protein expression levels of p-STAT3 in Eca109, Kyse150 and TE1 were 1.44±0.26, 0.75±0.04 and 1.92±0.17, higher than 0.18±0.05, 0.48±0.02 and 0.36±0.06 of the 0 Gy group (P<0.01). IL-6 protein expression increased significantly after different doses of irradiation (P<0.01). After the IL-6/STAT3 signaling pathway was blocked by the specific inhibitor AG490, the expressions of PD-L1 of Eca109, Kyse150 and TE1 in the 6 Gy+ AG490 groups were 0.11±0.03, 1.07±0.08 and 0.96±0.11, without significant differences of 0.09±0.01, 0.96±0.05 and 0.85±0.09 of the 0 Gy group (P>0.05), while the protein expressions of p-STAT3 were 0.76±0.11, 0.59±0.06 and 0.96±0.12, without significant differences of 0.67±0.08, 0.54±0.06 and 0.84±0.11 of the 0 Gy group (P>0.05). Conclusion: Radiotherapy may regulate the expression of PD-L1 in esophageal cancer cells through IL-6 / STAT3 signaling pathway.

CXCL5 inhibits tumor immune of lung cancer via modulating PD1/PD-L1 signaling / 中华肿瘤杂志

Objective: To investigate the role of CXCL5 in tumor immune of lung cancer and to explore the potential molecular mechanisms. Methods: A total of 62 cases of patients with lung cancer admitted in the First Affiliated Hospital of Henan University from May 2018 to December 2019 were recruited as study object. Another 20 cases of patients with pulmonary infectious diseases and 20 cases of healthy control were selected as control. Enzyme-linked immunosorbent assay (ELISA) was used to determine serum levels of CXCL5 in patients with lung cancer, pulmonary infectious diseases and healthy control. Immunohistochemical staining (IHC) was used to detect the expressions of CXCL5 and PD-1/PD-L1 in tumor and paracarcinoma tissues of patients with lung cancer. Pearson correlation analysis was used to evaluate the correlation between CXCL5 and PD-1 in tumor and paracarcinoma tissues of patients with lung cancer. Lewis cells either expressing CXCL5 or vector plasmids were used to establish C57BL/6J mice model of lung cancer, and all mice were then divided into vehicle and PD-1 antibody treatment groups, 10 mice for each group. The mice survival and tumor growth curves were recorded. IHC was used to evaluate the expressions of CXCL5, PD-1 as well as the proportions of CD8(+) T and Treg cells in xenograft tumor tissues. Results: In patients with lung cancer, the serum level of CXCL5 [(351.7±51.5) ng/L] was significant higher than that in patients with pulmonary infectious diseases and healthy control [(124.7±23.4) ng/L, P<0.001]. The expression levels of CXCL5 (0.136±0.034), CXCR2 (0.255±0.050), PD-1 (0.054±0.012) and PD-L1 (0.350±0.084) in tumor were significant higher than those in paracarcinoma normal tissues [(0.074±0.022), (0.112±0.023), (0.041±0.007) and (0.270±0.043) respectively, P<0.001]. CXCL5 was significant positively correlated with PD-1 in tumor tissues of lung cancer (r=0.643, P<0.001), but not correlated with PD-1 in paracarcinoma tissues(r=0.088, P=0.496). The vector control group, CXCL5 overexpression group, vector control + anti-PD-1 antibody treatment group and CXCL5 overexpression + anti-PD-1 antibody treatment group all successfully formed tumors in mice, while CXCL5 overexpression increased the tumor growth significantly (P<0.01), which was abrogated by the treatment of anti-PD-1 antibody. CXCL5 overexpression decreased the mice survival time significantly (P<0.01), this effect was also abrogated by the treatment of anti-PD-1 antibody. The proportion of CD8(+) T cells in CXCL5 overexpression group [(10.40±2.00)%] was significant lower than that in vector control group [(21.20±3.30)%, P=0.002]. The proportion of CD4(+) Foxp3(+) Treg cells in CXCL5 overexpression group [(38.40±3.70)%] was significant higher than that in vector control group [(23.30±2.25)%, P<0.001]. After the treatment of anti-PD-1 antibody, no significant difference were observed for the proportion of CD8(+) T cells [(34.10±5.00)% and (33.40±4.00)% respectively] and Treg cells [(14.70±3.50)% and (14.50±3.30)% respectively] in xenograft tumor tissues between CXCL5 overexpression+ anti-PD-1 antibody treatment group and vector control + anti-PD-1 antibody treatment group (P>0.05). Conclusion: The expressions of CXCL5 and PD-1/PD-L1 are all increased significantly in the tumor tissues of patients with lung cancer, CXCL5 may inhibit tumor immune of lung cancer via modulating PD-1/PD-L1 signaling.

Expression of PD-L1 and PD-1 in Pathological Tissue of Patients Newly Diagnosed with Diffuse Large B-Cell Lymphoma / 中国实验血液学杂志

OBJECTIVE@#To investigate the expression of PD-L1 and PD-1 in pathological tissue of patients newly diagnosed with diffuse large B-cell lymphoma (DLBCL).@*METHODS@#Data of DLBCL patients who visited the Department of Hematology, Peking University Third Hospital from May 2014 to March 2017 were collected, and a total of 21 patients with pathological tissue sections which were still available at the initial treatment were selected. The patients were divided into complete remission (CR) group and refractory relapse (RR) group according to clinical outcome. The expression and proportion of PD-1 and PD-L1 in pathological tissue sections were detected by multiplex fluorescence immunohistochemical staining, and the differences in the expression of different molecular markers in different clinical characteristics and different prognosis were compared using non-parametric test.@*RESULTS@#The ratio of PD-L1+ cells to PD-1+ cells (PD-L1+ : PD-1+) was 5.14±3.825 in increased lactate dehydrogenase (LDH) group, which was significantly higher than 0.76±0.563 in non-increased LDH group (P=0.001). The ratio of PD-L1+ : PD-1+ in increased Treg cells group was 1.41±1.454, which was lower than 6.42±4.426 in decreased Treg cells group (P=0.023).@*CONCLUSION@#The increased expression ratio of PD-L1 to PD-1 in pathological tissue sections of newly diagnosed DLBCL patients is associated with poor prognostic clinical characteristics.

Inhibitory Effect of Interference with PD-L1 Expression on B-cell lymphoma in Mice / 中国实验血液学杂志

OBJECTIVE@#To investigate the potential inhibitory effect of interference with PD-L1 on B cell lymphoma in mice.@*METHODS@#Three shRNA vectors for mouse CD274 (PD-L1) were constructed and transiently transfected into 293T cells. RT-qPCR was used to validate the interference efficiency of CD274. The shRNA vector that interfere efficiently with CD274 expression was packaged by using lentivirus packaging system to generate shRNA lentivirus, and then transfected into A20 lymphoma cell line. The methyl thiazol terazolium (MTT) assay was used to detect proliferation after 48 h culture of CD274-sh A20 cells. Meanwhile, BALB/c mice were hypodermically infected with CD274-sh A20 cells. Infected mice were observed daily and assessed to visualize tumor by in vivo fluorescence imaging.@*RESULTS@#The proliferation rate of CD274-sh A20 cells in vitro was significantly lower than that of A20 cells (P<0.05). The tumor size detected by in vivo fluorescence imaging showed a significant reduce in tumor bearing mice with CD274-sh compared with other tumor bearing mice. And the weight and size of tumor in CD274-sh group were also significantly reduced compared with other group (P<0.05). Moreover, the survival time of tumor bearing mice in CD274-sh group was longer than that of the PD-L1 high expression group.@*CONCLUSION@#PD-L1 plays an important role in the incidence and the progression of lymphoma, and the shRNA-based PD-L1 knockdown can inhibit cell proliferation of A20 cells and partly suppress tumor growth.

Comparative Study of PD-L1 Expression in Different Sites of Non-small Cell Lung Cancer / 中国肺癌杂志

BACKGROUND@#The expression of programmed cell death ligand 1 (PD-L1) as a biomarker for immunotherapy in non-small cell lung cancer (NSCLC) is routinely detected in clinical pathology department. However, the spatial heterogeneity of PD-L1 expression in intrapulmonary tumors and extrapulmonary metastases is still a challenge for the clinical testing. This study aims to explore the differences of PD-L1 expression in test samples obtaining from different sites of NSCLC. This study may contribute to the detection strategy of PD-L1 in patients with advanced lung cancer.@*METHODS@#One hundred and thirty-one cases of consecutively detected PD-L1 (22c3 assay, Dako) staining in metastatic NSCLC and 972 cases of non-paired intrapulmonary NSCLC were collected. The discrepancies of tumor proportion score (TPS) of PD-L1 expression in intrapulmonary samples and extrapulmonary metastatic samples of different sites were compared.@*RESULTS@#The positive expression rate of PD-L1 in extrapulmonary metastatic NSCLC (TPS ≥ 1%) was 61.83%, and the TPS was significantly higher than that in intrapulmonary tumors (P=0.03). The PD-L1 scores of the specimens obtained from different sites were significantly different (P=0.007). The positive rates of PD-L1 in liver and adrenal metastases were 85.71% and 77.78% respectively, and their TPS were significantly higher than that of the intrapulmonary samples (P<0.05). The positive rates of PD-L1 in lymph node, bone, brain, soft tissue, and pleural metastases was 40.00%-66.67%, with no significant differences compared to intrapulmonary tumors. The analysis of histological subtype and sample type showed that the PD-L1 score of extrapulmonary samples of adenocarcinoma subtype or surgical specimen was significantly higher than that of intrapulmonary tumors. The analysis of clinicopathological parameters showed that the PD-L1 positive expression or high expression were significantly correlated with male patients, smoking history, and epidermal growth factor receptor (EGFR) wild type.@*CONCLUSIONS@#The expression of PD-L1 in metastatic NSCLC is generally higher than that in intrapulmonary tumor, and the positive rate of PD-L1 expression was discrepant in different sites of specimen. The differences of PD-L1 score between extrapulmonary metastatic samples and intrapulmonary samples may be associated with different metastatic sites, histological subtype, and specimen type.

Dual Immunotherapy in Advanced Non-small Cell Lung Cancer: the Progress and Clinical Application / 中国肺癌杂志

Programmed cell death protein-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) inhibitors and PD-1 inhibitors plus chemotherapy combination regimens have been widely used in the first-line treatment of advanced non-small cell lung cancer(NSCLC), but patients with low PD-L1 expression have limited objective response and survival benefits. Existing treatment regimens are still difficult to fully meet the clinical needs of patients in the real world. Therefore, researchers are still exploring novel superactive treatment options to further improve the efficacy and survival prognosis of different sub-groups in NSCLC. Dual immunotherapy [such as the combination of PD-1 and cytotoxic T lymphocyte associated antigen-4 (CTLA-4) inhibitors] has shown considerable long-term survival benefits in a variety of tumors and has also shown broad clinical prospects in NSCLC. In addition to exploring different emerging combination options, how to accurately identify the optimal-benefit groups through predictive biomarkers and how to effectively manage the safety of combination immunotherapy through multidisciplinary collaboration are also the focus of dual immunotherapy. This article reviews the mechanism of action, research progress, predictive biomarkers and future exploration directions of dual immunotherapy.
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Blockade of PD-L1/PD-1 signaling promotes osteo-/odontogenic differentiation through Ras activation / 国际口腔科学杂志·英文版

The programmed cell death ligand 1 (PD-L1) and its receptor programmed cell death 1 (PD-1) deliver inhibitory signals to regulate immunological tolerance during immune-mediated diseases. However, the role of PD-1 signaling and its blockade effect on human dental pulp stem cells (hDPSCs) differentiation into the osteo-/odontogenic lineage remain unknown. We show here that PD-L1 expression, but not PD-1, is downregulated during osteo-/odontogenic differentiation of hDPSCs. Importantly, PD-L1/PD-1 signaling has been shown to negatively regulate the osteo-/odontogenic differentiation of hDPSCs. Mechanistically, depletion of either PD-L1 or PD-1 expression increased ERK and AKT phosphorylation levels through the upregulation of Ras enzyme activity, which plays a pivotal role during hDPSCs osteo-/odontogenic differentiation. Treatment with nivolumab (a human anti-PD-1 monoclonal antibody), which targets PD-1 to prevent PD-L1 binding, successfully enhanced osteo-/odontogenic differentiation of hDPSCs through enhanced Ras activity-mediated phosphorylation of ERK and AKT. Our findings underscore that downregulation of PD-L1 expression accompanies during osteo-/odontogenic differentiation, and hDPSCs-intrinsic PD-1 signaling inhibits osteo-/odontogenic differentiation. These findings provide a significant basis that PD-1 blockade could be effective immunotherapeutic strategies in hDPSCs-mediated dental pulp regeneration.

PKD3 promotes metastasis and growth of oral squamous cell carcinoma through positive feedback regulation with PD-L1 and activation of ERK-STAT1/3-EMT signalling / 国际口腔科学杂志·英文版

Oral squamous cell carcinoma (OSCC) has a high incidence of metastasis. Tumour immunotherapy targeting PD-L1 or PD-1 has been revolutionary; however, only a few patients with OSCC respond to this treatment. Therefore, it is essential to gain insights into the molecular mechanisms underlying the growth and metastasis of OSCC. In this study, we analysed the expression levels of protein kinase D3 (PKD3) and PD-L1 and their correlation with the expression of mesenchymal and epithelial markers. We found that the expression of PKD3 and PD-L1 in OSCC cells and tissues was significantly increased, which correlated positively with that of mesenchymal markers but negatively with that of epithelial markers. Silencing PKD3 significantly inhibited the growth, metastasis and invasion of OSCC cells, while its overexpression promoted these processes. Our further analyses revealed that there was positive feedback regulation between PKD3 and PD-L1, which could drive EMT of OSCC cells via the ERK/STAT1/3 pathway, thereby promoting tumour growth and metastasis. Furthermore, silencing PKD3 significantly inhibited the expression of PD-L1, and lymph node metastasis of OSCC was investigated with a mouse footpad xenograft model. Thus, our findings provide a theoretical basis for targeting PKD3 as an alternative method to block EMT for regulating PD-L1 expression and inhibiting OSCC growth and metastasis.

PD-1/PD-L1 regulates Treg differentiation in pregnancy-induced hypertension

Pregnancy-induced hypertension (PIH) causes significant maternal and fetal morbidity and mortality. A decreased number of regulatory T (Treg) cells is associated with the pathogenesis of PIH. The programmed cell death-1 (PD-1)/PD-ligand 1 (PD-L1) pathway is critical to normal pregnancy (NP) by promoting Treg cell development. However, the relationship between PD-1/PD-L1 and Treg differentiation in PIH has not been fully elucidated. In this study, venous blood was obtained from 20 NP and 58 PIH patients. Peripheral blood mononuclear cells (PBMCs) were isolated from venous blood. The levels of Treg-related cytokines (TGF-β, IL-10, and IL-35) in serum and PBMCs were measured by ELISA. The percentage of Treg cells in PBMCs was assessed by flow cytometry. The mRNA levels of Treg-specific transcription factor Foxp3 in PBMCs, and PD-1 and PD-L1 in Treg cells were detected by qRT-PCR. The protein levels of PD-1 and PD-L1 in Treg cells were evaluated by western blot. The serum levels of TGF-β, IL-10, IL-35, and Foxp3 mRNA expression and CD4+CD25+ Treg cell percentage in PBMCs were decreased in PIH. Furthermore, a significant increase of PD-1 in Treg cells was found in PIH compared with NP. In addition, PD-L1 Fc, an activator of PD-1/PD-L1 pathway, increased Treg cell percentage, enhanced Foxp3 mRNA expression, and elevated levels of TGF-β, IL-10, and IL-35 in PBMCs. However, anti-PD-L1 mAb exerted a reverse effect. These findings revealed that PD-L1 Fc had a favorable effect on Treg cell differentiation, indicating a potential therapeutic value of PD-1/PD-L1 pathway for PIH treatment.