Clinicopathological characteristics and prognosis of Epstein-Barr virus-associated gastric cancer.

OBJECTIVE: Epstein-Barr virus (EBV)-associated gastric cancer (EBVaGC) is a distinct molecular subtype of gastric cancer (GC). At present, the clinical characteristics and prognostic implications of EBV infection and the potential clinical benefits of immune checkpoint blockade in GC remain to be clarified. Hence, this study was designed to analyze the clinical and pathological characteristics of GC patients with varying EBV infection states and compare their overall survival (OS). METHODS: A retrospective study was performed on 1031 consecutive GC patients who underwent gastrectomy at the Affiliated Hospital of Xuzhou Medical University from February 2018 to November 2022. EBV-encoded RNA (EBER) in situ hybridization (ISH) was used for EBV assessment, and immunohistochemical staining was used for evaluation of human epidermal growth factor receptor 2 (HER2), programmed death ligand 1 (PD-L1), and Ki67 expression. EBVaGC was defined as tumors with EBV positivity. In addition, EBV-negative GC (EBVnGC) patients were matched with EBVaGC patients based on seven clinicopathological parameters (age, gender, anatomic subsite, tumor size, Lauren classification, degree of differentiation, and tumor-node-metastasis [TNM] stage). The correlations of clinical features with HER2, PD-L1, and Ki67 expression were evaluated statistically. The survival of patients was assessed through medical records, telephone, or WeChat communication, and prognostic analysis was performed using the logrank test as well as univariable and multivariable regression analysis. RESULTS: Out of 1031 GC patients tested, 35 (3.4%) were diagnosed with EBVaGC. Notably, the EBVaGC group exhibited a distinct predominance of males and younger patients, significantly higher Ki67 and PD-L1 expression levels, and a lower prevalence of pericancerous nerve invasion than the EBVnGC group (P < 0.01). In the 35 EBVaGC cases, Ki67 expression was negatively correlated with age (P < 0.05), suggesting that a younger onset age was associated with higher Ki67 expression. In addition, PD-L1 expression was correlated with the degree of differentiation, T-stage, and clinical stage of the patient. Furthermore, PD-L1 expression was elevated in tumors with lower differentiation or at later stages (P < 0.05). Using univariate analysis, Ki67, PD-L1, and clinical stage were identified as significant factors influencing the overall survival (OS) of EBVaGC patients (P < 0.05). Moreover, multivariate survival analysis revealed that clinical stage and Ki67 expression were independent risk factors for the OS of the patients (P < 0.05), and the three-year OS rate of EBVaGC patients was 64.2%. CONCLUSION: EBV-ISH is a practical and valuable method to identify EBVaGC. Owing to its unique etiological, pathological, and clinical characteristics, patients with EBVaGC might benefit from immune checkpoint blockade therapy.

Comparing Safety and Efficacy of TACE + Apatinib in Combination with a PD-1 Inhibitor versus a Non-triple Therapy for Treating Advanced Primary Hepatocellular Carcinoma: A Systematic Review and Meta-analysis.

BACKGROUND AND AIMS: This meta-analysis was performed to compare the efficacy and safety of a triple therapy, involving transcatheter arterial chemoembolization (TACE) + apatinib combined with a programmed-cell death protein-1 (PD-1) inhibitor versus TACE + apatinib, a dual therapy with apatinib and PD-1 inhibitor, and TACE alone for the treatment of advanced primary hepatocellular carcinoma (HCC). METHODS: A computerized systematic search of databases, such as PubMed, Embase, the Cochrane Library, CNKI, Wanfang Data, and VIP e-Journals was performed to retrieve studies comparing TACE + apatinib combined with a PD-1 inhibitor versus a non-triple therapy for the treatment of advanced primary HCC. The literature search, quality assessment, and data extraction were performed independently by two researchers. Stata 16.0 software was employed to analyze the data. Heterogeneity was assessed utilizing the I2 statistic and p-value, followed by conducting sensitivity analysis. RESULTS: A total of 2,352 patients were enrolled from 8 studies, including 900 patients in the triple therapy group of TACE + apatinib combined with a PD-1 inhibitor, 877 patients in the TACE + apatinib group, 52 patients in the apatinib + a PD-1 inhibitor group, and 112 patients in the TACE group. The results revealed that the objective response rate (ORR) was significantly higher in the triple therapy group of TACE + apatinib combined with a PD-1 inhibitor than that in the non-triple therapy group [odds ratio (OR)=2.47, 95% confidence interval (95%CI): 1.61-3.78]. Besides, disease control rate (DCR) was greater in the triple therapy group of TACE + apatinib combined with a PD-1 inhibitor than that in the non-triple therapy group (OR=1.87, 95%CI: 1.44-2.44). Patients in the triple therapy group experienced a significant extension of overall survival (OS) (HR=0.42, 95%CI: 0.36-0.49). In addition, there was no significant difference in the overall rate of adverse events (AEs) between the two groups (OR=1.05, 95%CI: 0.89-1.22). CONCLUSIONS: Compared with the non-triple therapy group, the triple therapy group of TACE + apatinib combined with a PD-1 inhibitor outperformed in terms of tumor response and long-term survival with manageable AEs.

Progress in the treatment of advanced hepatocellular carcinoma with immune combination therapy.

Advanced hepatocellular carcinoma (HCC) is a severe malignancy that poses a serious threat to human health. Owing to challenges in early diagnosis, most patients lose the opportunity for radical treatment when diagnosed. Nonetheless, recent advancements in cancer immunotherapy provide new directions for the treatment of HCC. For instance, monoclonal antibodies against immune checkpoint inhibitors (ICIs) such as programmed cell death protein 1/death ligand-1 inhibitors and cytotoxic t-lymphocyte associated antigen-4 significantly improved the prognosis of patients with HCC. However, tumor cells can evade the immune system through various mechanisms. With the rapid development of genetic engineering and molecular biology, various new immunotherapies have been used to treat HCC, including ICIs, chimeric antigen receptor T cells, engineered cytokines, and certain cancer vaccines. This review summarizes the current status, research progress, and future directions of different immunotherapy strategies in the treatment of HCC.

Clinicopathological features, psychological status, and prognosis of 33 patients with occult breast cancer.

BACKGROUND: Occult breast cancer (OBC) has traditionally been considered to be a carcinoma of unknown primary origin with a favorable prognosis and can be treated as stage II-III breast cancer. Due to the small number of cases and limited clinical ex-perience, treatments vary greatly around the world and no standardized treat-ment has yet been established. AIM: To investigate the clinicopathological features, psychological status and prog-nostic features of patients with OBC. METHODS: The clinicopathological data of 33 OBC patients diagnosed and treated in the Affiliated Hospital of Xuzhou Medical University and Xuzhou Central Hospital from November 2015 to November 2022 were retrospectively analyzed. The psychological status of OBC patients was evaluated by the Self-rating Anxiety Scale and Self-rating Depression Scale. Patients' emotions, stress perception and psychological resilience were evaluated by the Positive and Negative Affect Schedule, the Chinese Perceived Stress Scale, and the Connor-Davidson Resilience Scale (CD-RISC), respectively. Patient survival was calculated using the Kaplan-Meier method, and survival curves were plotted for analysis with the log-rank test. Univariate and multivariate survival analyses were performed using the Cox regression model. RESULTS: The 33 OBC patients included 32 females and 1 male. Of the 33 patients, 30 (91%) had axillary tumors, 3 (9%) had a neck mass as the primary symptom; 18 (54.5%) had estrogen receptor-positive tumors, 17 (51.5%) had progesterone receptor-positive tumors, and 18 (54.5%) had Her-2-positive tumors; 24 (72.7%) received surgical treatment, including 18 patients who underwent modified radical mastectomy, 1 patient who underwent breast-conserving surgery plus axillary lymph node dissection (ALND), and 5 patients who underwent ALND alone; 12 patients received preoperative neoadjuvant therapy. All 30 patients developed anxiety and depression, with low positive affect scores and high negative affect scores, accompanied by a high stress level and poor psychological resilience. There were no differences in the psychological status of patients according to age, body mass index, or menopausal status. The overall survival and disease-free survival (DFS) of all the patients were 83.3% and 55.7%, respectively. Univariate analysis demonstrated that the initial tumor site (P = 0.021) and node stage (P = 0.020) were factors that may affect patient prognosis. The 5-year DFS rate of OBC patients who received radiotherapy was greater (P < 0.001), while the use of different surgical methods (P = 0.687) had no statistically significant effect on patient outcomes. Multivariate analysis revealed that radiotherapy (P = 0.031) was an independent prognostic factor. Receiving radiotherapy had a significant effect on the CD-RISC score (P = 0.02). CONCLUSION: OBC is a rare breast disease whose diagnosis and treatment are currently controversial. There was no significant difference in the efficacy of other less invasive surgical procedures compared to those of modified radical mastectomy. In addition, radiotherapy can significantly improve patient outcomes. We should pay attention to the psychological state of patients while they receive antitumor therapy.

Systematic pan-cancer analysis identified neuropilin 1 as an immunological and prognostic biomarker.

Neuropilin 1 (NRP1) is a transmembrane glycoprotein, nontyrosine kinase receptor that plays an important role in axonal growth and angiogenesis in the nervous system. Although currently more and more studies have shown that NRP1 plays an important role in some cancers, no systematic pan-cancer analysis of NRP-1 has been performed to date. Therefore, we aimed to investigate the associated immune function and prognostic value of NRP1 in 33 tumors of various cancer types. In this study, based on The Cancer Genome Atlas, Cancer Cell Line Encyclopedia, Genotype Tissue Expression, cBioportal for cancer genomics, and Human Protein Atlas (HPA databases), various bioinformatics analysis methods were used to investigate the potential carcinogenic effects of NRP1 activation, pan-cancer analysis of NRP1 expression, and the relationship between NRP1 expression and prognosis indicators including overall survival, disease-specific survival, disease-free interval, and progression-free interval, tumor mutational burden (TMB), and microsatellite instability (MSI). The results showed that NRP1 was highly expressed in most tumors. In addition, NRP1 was found to be positively or negatively correlated with the prognosis of different tumors. Also, the expression of NRP1 was associated with TMB and MSI in in 27 and 21 different types of tumors, respectively, and with DNA methylation in almost all the various types of tumors. The expression of the NRP1 gene was negatively correlated with the infiltration levels of most immune cells. In addition, the correlation between the level of immune cell infiltration and NRP1 expression varied according to immune cell subtype. Our study suggests that NRP1 plays an important role in tumor development and tumor immunity and could potentially be used as a prognostic indicator in a variety of malignancies.

Safety and Efficacy of TACE + Lenvatinib in Treating Advanced Hepatocellular Carcinoma: A Systematic Review and Meta- analysis.

BACKGROUND AND AIMS: To compare the efficacy and safety of transarterial chemoembolization (TACE) + lenvatinib (TACE+L) versus lenvatinib (L) monotherapy in the treatment of advanced hepatocellular carcinoma by a meta-analysis. METHODS: PubMed, Embase, the Cochrane Library, CNKI, VIP e-Journals Database, and Wanfang Data were systematically searched to collate literature comparing TACE+L with L alone for the treatment of advanced liver cancer. The literature search, quality assessment, and data extraction were performed independently by two reviewers. The Stata 16 software package was used to process and analyze the data. We assessed heterogeneity using both I2 and the p-value, performed a publication bias assessment, and conducted a sensitivity analysis. RESULTS: Five studies were finally included, including one randomized controlled study and four retrospective studies; these involved a total of 1,167 patients, including 523 patients in the TACE+L combination group and 644 patients in the L monotherapy group. In this meta-analysis, the TACE+L group showed a significantly better objective response rate (ORR) (OR=2.54, 95%CI: 1.34 - 4.80) and disease control rate (DCR) compared to the L monotherapy group (OR=2.68, 95%CI: 1.75 - 4.08). The combined group had significantly improved progression-free survival (PFS) (HR=0.47, 95%CI: 0.40 - 0.56) and overall survival (OS) (HR=0.48, 95%CI: 0.39-0.59). In addition, there was no significant difference found in the overall adverse events of any grade between the two groups (OR=1.13, 95%CI: 0.99 - 1.29). CONCLUSIONS: Compared to L alone, TACE+L treatment resulted in better tumor response, better long-term survival, and was accompanied by controllable adverse events.

Concurrent chemoradiotherapy followed by adjuvant chemotherapy versus concurrent chemoradiotherapy alone in locally advanced cervical cancer: A systematic review and meta-analysis.

Objective: This study aimed to assess the efficacy and safety of adjuvant chemotherapy (ACT) after concurrent chemoradiation (CCRT) in patients with locally advanced cervical cancer (LACC) via meta-analysis. Methods: A systematic literature search of MEDLINE, PubMed, Web of Science, EMBASE, and the Cochrane Central Register of Controlled Trials was conducted from January 10, 1966 to May 20, 2022. Randomized controlled trials and observational studies comparing the CCRT alone with CCRT plus ACT were included. The literature search, quality assessment, and data extraction were conducted by two reviewers independently. The primary endpoints were 3-year rates of overall survival (OS) and progression-free survival (PFS). Complete response rate, local recurrence, distant metastasis, and adverse events were secondary outcomes. The hazard ratios (HRs) and relative risk (RR) were pooled. Results: Nine studies with a total of 2732 patients were included in this meta-analysis, including 1411 patients in the CCRT group and 1321 in the CCRT plus ACT group. The HR for 3-year rates of OS and PFS of the CCRT group compared with the CCRT plus ACT group was 0.72 [95%confidence interval (CI) = 0.44-1.17] and 0.78 (95%CI = 0.5-1.75), respectively. No significant differences were observed between the two groups in the complete response rate (RR = 1.06, 95%CI = 0.96-1.16). However, local recurrence and distant metastasis were significantly lower in the CCRT plus ACT group than in the CCRT group (RR = 0.63, 95%CI = 0.44 -0.91 and RR = 0.64, 95%CI = 0.47-0.88). Grade 3-4 acute toxicities were more frequent in the CCRT plus ACT group (RR = 1.73, 95%CI =1.19-2.52). Conclusion: Although associated with a decreased risk of local recurrence and distant metastasis, ACT did not significantly improve the survival rate and the complete response rate with increasing grade 3-4 acute toxicities in patients with LACC. Thus, this ACT regimen cannot be recommended for patients with LACC. Systematic review registration: https://inplasy.com/inplasy-2022-9-0089/, identifier INPLASY202290089.

Comparison of Hepatic Arterial Infusion Chemotherapy and Transarterial Chemoembolization for Advanced Hepatocellular Carcinoma: A Systematic Review and Meta-Analysis.

AIMS: To compare the efficacy, safety, and survival outcomes of hepatic arterial infusion chemotherapy (HAIC) versus transarterial chemoembolization (TACE) for the treatment of advanced hepatocellular carcinoma (HCC), a comprehensive meta-analysis was conducted. METHODS: MEDLINE, PubMed, Web of Science, Embase, and the Cochrane Central Register of Controlled Trials were searched from January 1966 to 20 February 2022, and relevant articles were retrieved. The literature search, quality assessment, and data extraction were conducted independently by two reviewers. The primary endpoints were objective response rate (ORR) and overall survival (OS), while the secondary endpoints were disease control rate (DCR), progression-free survival (PFS), and adverse events. The odd ratios (OR) and hazard ratios (HR) with 95% confidence intervals (95%CI) were pooled. RESULTS: Seven studies with a total of 989 patients were included in this meta-analysis. The pooled results showed that HAIC significantly improved ORR (OR=4.94, 95%CI: 3.47-7.05, p<0.001) and DCR (OR=2.97, 95%CI: 2.16-4.08, p<0.001). In addition, HCC patients who received HAIC had significantly longer PFS (HR=0.54, 95%CI: 0.45-0.65, p<0.001) and OS (HR=0.55, 95%CI: 0.46-0.66, p<0.001) than those who underwent TACE. Compared with TACE, HAIC showed a lower incidence for grade 3-4 adverse events (OR=0.52, 95%CI: 0.30-0.88, p<0.001). CONCLUSIONS: HAIC may significantly improve survival benefits and exhibit higher local treatment responses with mild side effects in patients with advanced HCC compared to TACE.

Comparison of effectiveness and safety of camrelizumab between HBV-related and non-B, non-C hepatocellular carcinoma: A retrospective study in China.

Purpose: This study aimed to compare the clinical outcomes of camrelizumab in hepatitis B virus-related hepatocellular carcinoma (HBV-HCC) patients and non-HBV, non-HCV hepatocellular carcinoma (NBNC-HCC) patients in China. Materials and methods: A total of 54 patients with hepatocellular carcinoma who received camrelizumab were included in this retrospective study from January 2019 to December 2021. The patients were assigned to the HBV-HCC group (n = 28) and the NBNC-HCC group (n = 26). The primary endpoints were overall survival (OS) and progression-free survival (PFS), and the secondary endpoints were the objective response rate (ORR), disease control rate (DCR), and adverse events (AEs). Multivariate analysis using Cox proportional hazard regression was used to identify independent prognostic factors. A nomogram model was subsequently established based on independent prognostic factors. Results: The mean duration of follow-up was 12.7 ± 3.6 months. The median OS was not determined. The median PFS in the HBV-HCC group was significantly longer than that in the NBNC-HCC group (9.2 vs. 6.7 months, p = 0.003). The ORR and DCR in the HBV-HCC group were significantly higher than those in the NBNC-HCC group (ORR, 28.6% vs. 7.7%, p = 0.048; DCR, 71.4% vs. 42.3%, p = 0.031). No significant differences in the total incidence of AEs were found between the HBV-HCC group and the NBNC-HCC group (75.0% vs. 69.2%, p = 0.224). Multivariate regression analysis identified etiology, AFP level, and vascular invasion as independent prognostic factors (all p < 0.05). Conclusion: Our findings demonstrate that camrelizumab is more effective in HBV-HCC patients than in NBNC-HCC patients, with manageable safety.

Knockdown of replication protein A 3 induces protective autophagy and enhances cisplatin sensitivity in lung adenocarcinoma by inhibiting AKT/mTOR signaling via binding to cyclin-dependent kinases regulatory subunit 2.

Replication protein A 3 (RPA3) is a significant component of replication protein A and has been documented to function as an oncogene in several types of cancers. However, the role and underlying mechanism of RPA3 in lung adenocarcinoma (LUAD) remains unknown. In this study, messenger expression of RPA3 and survival probability in LUAD were predicted by the UALCAN database. The combination of RPA3 with cyclin-dependent kinases regulatory subunit 2 (CKS2) were characterized by the humanbase and STRING databases and verified by co-immunoprecipitation. Cell viability was assessed by Cell Counting Kit-8 assay and colony formation assay. Flow cytometric analysis and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay were used to determine cell cycle and cell apoptosis, respectively. The expressions of protein kinase B/mammalian target of rapamycin (AKT/mTOR) pathway and autophagy-related proteins were examined by western blot assay. Significantly, we revealed that RPA3 expression was upregulated in LUAD and is associated with poor prognosis in LUAD patients. RPA3 and CKS2 expression was highly expressed in LUAD cell lines and the interaction between RPA3 and CKS2 was confirmed. RPA3 silencing inhibited A549 cell viability, blocked cell cycle and promoted cell apoptosis, as well as induction of autophagy and inhibition of AKT/mTOR signaling. CKS2 overexpression reversed the effects of RPA3 silencing on A549 cells. In addition, RPA3 knockdown enhanced cisplatin sensitivity of A549 cells through blocking the AKT/mTOR signaling. These results suggested that RPA3 might control LUAD cell autophagy and enhance cisplatin sensitivity by regulation of AKT/mTOR signaling via targeting CKS2.

Origin recognition complex 1 regulates phospholipase Cδ1 to inhibit cell proliferation, migration and epithelial-mesenchymal transition in lung adenocarcinoma.

As a common pulmonary malignant disease, lung adenocarcinoma exhibits high mortality and morbidity rate. Phospholipase Cδ1 (PLCD1), an enzyme involved in the homeostasis of energy metabolism, is downregulated in lung adenocarcinoma. According to GEPIA, origin recognition complex 1 (ORC1) is a highly expressed gene in lung adenocarcinoma and is negatively associated with PLCD1. To the best of our knowledge, the present study was the first to investigate the role of ORC1 in regulating PLCD1 in lung adenocarcinoma. According to TCGA database, low expression of PLCD1 was correlated with the low overall survival rate of patients suffering from lung adenocarcinoma. The protein and mRNA expression levels of PLCD1 and ORC1 were detected in A549 cells by western blot analysis and reverse transcription-quantitative PCR, respectively. Cell proliferation, invasion and migration were analyzed by MTT, colony formation, Transwell and wound healing assay. Immunofluorescence staining was adopted to estimate the content of Ki67 and western blot was applied for the evaluation of PLCD1, MMP2, MMP9, E-cadherin, N-cadherin, vimentin, Snail and ORC. The binding interaction between ORC1 and PLCD1 was analyzed using chromatin immunoprecipitation and luciferase reporter enzyme gene assays. The results indicated that PLCD1 was lowly expressed in lung adenocarcinoma cells in comparison with that in 16HBE. When PLCD1 was overexpressed in cancer cells, cell proliferation, invasion and migration were significantly inhibited. However, in the presence of both ORC1 and PLCD1 overexpression, the suppressive effects of PLCD1 overexpression alone on cell proliferation, invasion, migration and EMT were attenuated. In conclusion, ORC1 was indicated to inhibit PLCD1, thus regulating the proliferation, migration and EMT processes of lung adenocarcinoma cells, which suggested that ORC1 might be a target for the treatment of lung adenocarcinoma.

DNA damage promotes microtubule dynamics through a DNA-PK-AKT axis for enhanced repair.

DNA double-strand breaks (DSBs) are mainly repaired by c-NHEJ and HR pathways. The enhanced DSB mobility after DNA damage is critical for efficient DSB repair. Although microtubule dynamics have been shown to regulate DSB mobility, the reverse effect of DSBs to microtubule dynamics remains elusive. Here, we uncovered a novel DSB-induced microtubule dynamics stress response (DMSR), which promotes DSB mobility and facilitates c-NHEJ repair. DMSR is accompanied by interphase centrosome maturation, which occurs in a DNA-PK-AKT-dependent manner. Depletion of PCM proteins attenuates DMSR and the mobility of DSBs, resulting in delayed c-NHEJ. Remarkably, DMSR occurs only in G1 or G0 cells and lasts around 6 h. Both inhibition of DNA-PK and depletion of 53BP1 abolish DMSR. Taken together, our study reveals a positive DNA repair mechanism in G1 or G0 cells in which DSBs actively promote microtubule dynamics and facilitate the c-NHEJ process.

CPEB4 Inhibit Cell Proliferation via Upregulating p21 mRNA Stability in Renal Cell Carcinoma.

Cytoplasmic polyadenylation element-binding protein 4 (CPEB4) has been reported to be dysregulated in a variety of cancers and seems to play paradoxical roles in different cancers. However, the functional roles of CPEB4 in Renal cell carcinoma (RCC) are still unclear. This study aims to explore the role and underlying mechanism of CPEB4 in RCC. We found that the relative expression level of CPEB4 is down-regulated in RCC tissues and cell lines, and the low CPEB4 expression is correlated with short overall and disease-free survival of RCC patients. CPEB4 significantly inhibits RCC tumor growth both in vivo and in vitro. CPEB4 exerts an anti-tumor effect by increasing p21 mRNA stability and inducing G1 cell cycle arrest in RCC. Our data revealed that CPEB4 is a tumor suppressor gene that restrains cell cycle progression upstream of p21 in RCC. These findings revealed that CPEB4 may become a promising predictive biomarker for prognosis in patients with RCC.

EGFR E746-A750 deletion in lung cancer represses antitumor immunity through the exosome-mediated inhibition of dendritic cells.

EGFR-mutant lung cancer (LC) patients display a poor response to PD-1/PD-L1 blockade. In the absence of independent genetic validation, whether EGFR mutation distorts host antitumor immunity is unknown. Here, we showed that in the clinic, LC with the E746-A750 deletion mutation (EGFR-19del) displayed a temporal association with the loss of intratumoral CD8+ T cells. In a xenograft model, EGFR-19del-expressing Lewis lung cancer (LLC) tumors had a low T cell density at the early stage of tumor development, along with dendritic cells (DCs) exhibiting variant phenotypes in the tumors and draining lymph nodes (LNs). Importantly, EGFR-19del DCs were observed in the LNs of tumor-bearing mice and LC patients. The proliferative activity of T cells within the LN was significantly dampened. In vitro experiments indicated that the function of DCs was repressed by EGFR-19del LLC cells through exosome uptake in which exosomes derived from the EGFR-19del LLC cells could efficiently transfer active EGFR-19del to the surface of the DCs. Injection of EGFR-19del tumor-derived exosomes promoted LLC tumor progression and induced immunosuppression. The combination of gefitinib and GM-CSF treatment recovered tumor T cell infiltration in EGFR-19del tumors by rescuing the function of DCs and increasing the efficacy of anti-PD-L1 treatment. Together, these results indicated that LC with the EGFR E746-A750 deletion mutation induced anergic DCs to repress antitumor immunity through exosomes.

Akt/mTOR and AMPK signaling pathways are responsible for liver X receptor agonist GW3965-enhanced gefitinib sensitivity in non-small cell lung cancer cell lines.

BACKGROUND: This study was to systemically analyze the mechanism of LXR ligand GW3965-induced sensitivity to EGFR-TKI in EGFR-TKI-resistant non-small cell lung cancer (NSCLC) cell lines. METHODS: Gefitinib-resistant PC9 cell line (EGFR exon 19 deletion) was treated with single and combined treatment with GW3965 and gefitinib. Cell viability, apoptosis and autophagy were detected using MTT, flow cytometric analysis and immunofluorescent analysis, respectively. Autophagy-related signaling pathways were detected using Western blot analysis. RESULTS: Inhibited cell viability by single and combined treatment with gefitinib and GW3965 were observed. Combined treatment with gefitinib and GW3965 increased LC3 II/I ratio and Beclin 1 expression. Synergistic effect of gefitinib and GW3965 on apoptosis and autophagosome accumulation as well as on the inhibition of Akt/mTOR signaling and activation of AMP-activated protein kinase (AMPK) was observed in gefitinib-resistant PC9 cells. AMPK expression showed similar profile with apoptosis and autophagy of PC9 cells. CONCLUSIONS: We confirmed that GW3965 and gefitinib showed synergistic effect on Akt/mTOR inhibition, apoptosis and autophagy of lung cancer cells. Gefitinib sensitivity in PC9 cell line might be mediated by Akt/mTOR, AMPK and JNK signaling pathways.

Exosome-mediated gefitinib resistance in lung cancer HCC827 cells via delivery of miR-21.

Acquired resistance to gefitinib remains a major challenge in cancer treatment. In the present study, the effect of exosomes on the transmission of gefitinib resistance from gefitinib-resistant HCC827 lung cancer cells (H827R) to their gefitinib-sensitive counterparts and the potential underlying mechanisms by which this occurs was investigated. Exosomes were obtained from the cell supernatant using ultracentrifugation and the ExoQuick-TC exosome precipitation solution. Drug resistance was assessed by flow cytometry, apoptosis assays and cell counting kit-8 assays. The expression of microRNA (miR)-21 was analyzed by reverse transcription-quantitative polymerase chain reaction. Exosomes released by H827R cells (R/exo) may decrease the sensitivity of the human NSCLC HCC827 cell line to gefitinib. The results indicated that miR-21 expression was increased in R/exo and R/exo-treated H827S cells. However, miR-21 inhibition abrogated exosome-mediated drug resistance. Phosphorylated-protein kinase B (p-Akt), which is downstream of miR-21, was downregulated following gefitinib treatment; however, R/exo pretreatment elevated p-Akt levels and promoted the activation of Akt. By contrast, miR-21 inhibition reduced p-Akt expression. Therefore, the induction of miR-21 via exosomes and the activation of Akt may be mechanisms by which exosomes mediate the transfer of drug resistance.

MiRNA signature predicts the response of patients with advanced lung adenocarcinoma to platinum-based treatment.

BACKGROUND: Accumulating literature proved that miRNAs can regulate the sensitivity of platinum and act as a promising candidate to predict the response of patients with lung adenocarcinoma to chemotherapy. However, most studies on miRNAs were restricted to in vitro experiments. This study aimed to evaluate whether miRNAs alone or in combination (miRNA signature) can act as predictive biomarkers of platinum-based chemotherapy in patients with lung adenocarcinoma. METHODS: Eight miRNAs that most probably predict the efficacy of platinum were screened in 111 tumor tissues of lung adenocarcinoma. Univariate and multivariate Cox analyses, Kaplan-Meier survival curve analysis, Chi-square test, and univariate and multivariate logistic regression analyses were employed to determine whether miRNA expression is associated with the response of patients to platinum-based chemotherapy. The maximum significant odds ratio value was acquired by multiple cycles of multivariate logistic regression analysis. The cut-off points of miRNAs were obtained. A miRNA chemo-sensibility index (CI) formula was established, and its prediction performance was confirmed in another independent set (n = 31). RESULTS: Underexpression of three miRNAs (miRNA-21, miRNA-125b, and miRNA-224) was independently associated with the chemotherapy sensitivity of patients with lung adenocarcinoma. The miRNA CI formula containing these three miRNAs was calculated as (1.364 × miR-21) + (1.323 × miR-125b) + (1.131 × miR-224). A high CI was related to platinum-based chemotherapy resistance, and its prediction performance was confirmed in the testing set. The MAPK, PI3K-Akt, Ras, and cGMP-PKG signaling pathways were considered to be most probably correlated with platinum resistance. CONCLUSION: Our miRNA CI formula can act as an independent predictor to predict the response of patients with lung adenocarcinoma to platinum-based chemotherapy.

MicroRNA-106b-5p regulates cisplatin chemosensitivity by targeting polycystic kidney disease-2 in non-small-cell lung cancer.

Systemic therapy with cytotoxic agents remains one of the main treatment methods for non-small-cell lung cancer (NSCLC). Cisplatin is a commonly used chemotherapeutic agent, that, when combined with other drugs, is an effective treatment for NSCLC. However, effective cancer therapy is hindered by a patient's resistance to cisplatin. Unfortunately, the potential mechanism underlying such resistance remains unclear. In this study, we explored the mechanism of microRNA-106b-5p (miR-106b-5p), which is involved in the resistance to cisplatin in the A549 cell line of NSCLC. Quantitative real-time PCR was used to test the expression of miR-106-5p in the A549 and the A549/DDP cell line of NSCLC. The cell counting kit-8 assay was used to detect cell viability. Flow cytometry was used to measure cell cycle and cell apoptosis. Luciferase reporter assays and western blot were performed to confirm whether polycystic kidney disease-2 (PKD2) is a direct target gene of miR-106b-5p. Immunohistochemistry was performed to examine the distribution of PKD2 expression in patients who are sensitive and resistant to cisplatin. The experiments indicated that the expression of miR-106b-5p was significantly decreased in A549/DDP compared with that in A549. MiR-106b-5p affected the tolerance of cells to cisplatin by negatively regulating PKD2. Upregulation of miR-106b-5p or downregulation of PKD2 expression can cause A549/DDP cells to become considerably more sensitive to cisplatin. The results showed that miR-106b-5p enhanced the sensitivity of A549/DDP cells to cisplatin by targeting the expression of PKD2. These findings suggest that the use of miR-106b-5p may be a promising clinical strategy in the treatment of NSCLC.

Epithelial-to-mesenchymal transition correlates with gefitinib resistance in NSCLC cells and the liver X receptor ligand GW3965 reverses gefitinib resistance through inhibition of vimentin.

The role of epithelial-to-mesenchymal transition in cancer drug resistance is increasingly acknowledged. We examined whether epithelial-to-mesenchymal transition affects gefitinib resistance in non-small cell lung cancer (NSCLC) cells. Cell viability was detected by CCK-8 assay, VIM expression levels were determined by quantitative real-time polymerase chain reaction. Western blot and immunocytochemistry were performed to determine the protein expression level of vimentin. We observed morphologic differences between gefitinib-sensitive and -insensitive cells. Compared with the sensitive parental cell line, HCC827, vimentin expression levels were increased in HCC827 cells with acquired gefitinib resistance. Vimentin expression was also markedly upregulated in cells with intrinsic gefitinib resistance, and upregulated vimentin expression was correlated with gefitinib sensitivity. Our previous study demonstrated that coadministration of gefitinib and GW3965 resulted in decreased cell proliferation and induced apoptosis. Therefore, we investigated the relationship among GW3965, vimentin, and gefitinib resistance in NSCLC cells by analysis of the expression of vimentin in cells treated with a combination of gefitinib and GW3965. Gefitinib treatment led to increased levels of intracellular vimentin, while combined treatment with gefitinib and GW3965 resulted in decreased vimentin expression levels through reduction of gefitinib drug resistance in NSCLC cells. Overall, these findings suggest that vimentin expression is associated with sensitivity to gefitinib, and our study highlights the potential usefulness of the drug, GW3965, for reversal of gefitinib resistance through inhibition of vimentin expression.

Cisplatin-resistant lung cancer cell-derived exosomes increase cisplatin resistance of recipient cells in exosomal miR-100-5p-dependent manner.

Exosomes derived from lung cancer cells confer cisplatin (DDP) resistance to other cancer cells. However, the underlying mechanism is still unknown. A549 resistance to DDP (A549/DDP) was established. Microarray was used to analyze microRNA (miRNA) expression profiles of A549 cells, A549/DDP cells, A549 exosomes, and A549/DDP exosomes. There was a strong correlation of miRNA profiles between exosomes and their maternal cells. A total of 11 miRNAs were significantly upregulated both in A549/DDP cells compared with A549 cells and in exosomes derived from A549/DDP cells in contrast to exosomes from A549 cells. A total of 31 downregulated miRNAs were also observed. miR-100-5p was the most prominent decreased miRNA in DDP-resistant exosomes compared with the corresponding sensitive ones. Downregulated miR-100-5p was proved to be involved in DDP resistance in A549 cells, and mammalian target of rapamycin (mTOR) expression was reverse regulated by miR-100-5p. Exosomes confer recipient cells' resistance to DDP in an exosomal miR-100-5p-dependent manner with mTOR as its potential target both in vitro and in vivo. Exosomes from DDP-resistant lung cancer cells A549 can alter other lung cancer cells' sensitivity to DDP in exosomal miR-100-5p-dependent manner. Our study provides new insights into the molecular mechanism of DDP resistance in lung cancer.