High expression levels of FANCI correlate with worse prognosis and promote tumor growth of lung adenocarcinoma partly via suppression of M1 macrophages.

FANCI, a member of the Fanconi anemia (FA) complementation group, normally associates with FANCD2 to play an important role in ribosome biogenesis and DNA repair. However, the correlation of FANCI with prognostic value and the molecular mechanism in patients with lung adenocarcinoma (LUAD) remains unclear. In the present study, bioinformatics analysis was performed on LUAD data from TCGA and GEO databases, and further confirmed by in vitro experiments. We found that a high level of FANCI was significantly correlated with a worse survival probability in patients with LUAD. Moreover, the results from in vitro experiments revealed high levels of FANCI in LUAD specimens and cell lines. Knockdown of FANCI expression in A549 and H460 cells significantly inhibited cell viability and clone formation of LUAD cells in vitro and in vivo. Furthermore, high FANCI levels were negatively correlated with a variety of tumor-infiltrating immune cells. Importantly, the overexpression of FANCI significantly inhibited the activation of M1 macrophages. All the data demonstrated that FANCI was a useful prognostic biomarker in patients with LUAD, and knockdown of FANCI inhibited tumor growth of LUAD cells in vitro and in vivo, partly by suppressing the activation of M1 macrophages.

Construction of Lymph Node Metastasis-Related Prognostic Model and Analysis of Immune Infiltration Mode in Lung Adenocarcinoma.

Background: Lung adenocarcinoma (LUAD) is a major cause for global cancer-related deaths. Research reports demonstrate that lymph node metastasis (LNM) is pertinent to the survival rate of LUAD patients, and crux lies in the lack of biomarkers that could distinguish patients with LNM. We aimed to verify the LNM-related prognostic biomarkers in LUAD. Methods: We firstly accessed the expression data of mRNA from The Cancer Genome Atlas (TCGA) database and then obtained samples with LNM (N+) and without LNM (N-). Differential expression analysis was conducted to acquire differentially expressed genes (DEGs). Univariate-LASSO-multivariate Cox regression analyses were performed on DEGs to build a risk model and obtain optimal genes. Afterwards, effectiveness and independence of risk model were assessed based on TCGA-LUAD and GSE31210 datasets. Moreover, a nomogram was established combining clinical factors and riskscores. Nomogram performance was measured by calibration curves. The infiltration abundance of immune cells was scored with CIBERSORT to explore the differences between high- and low-risk groups. Lastly, gene set enrichment analysis (GSEA) was used to investigate differences in immune features between the two risk groups. Results: Nine optimal feature genes closely related to LNM in LUAD were identified to construct a risk model. Prognostic ability of the risk model was verified in independent databases. Patients were classified into high- and low-risk groups in accordance with their median riskscores. CIBERSORT score displayed differences in immune cell infiltration like T cells CD4 memory resting between high/low-risk groups. LNM-related genes may also be closely relevant to immune features. Additionally, GSEA indicated that differential genes in the two risk groups were enriched in genes related to immune cells. Conclusion: This research built a risk model including nine optimal feature genes, which may be potential biomarkers for LUAD.

TRIM55 suppresses malignant biological behavior of lung adenocarcinoma cells by increasing protein degradation of Snail1.

Up until now, cancer refractoriness and distal organ metastatic disease remain as major obstacles for oncologists to achieve satisfactory therapeutic effects for lung adenocarcinoma patients. Previous studies indicated that TRIM55, which participates in the natural development of muscle and cardiovascular system, plays a protective role in hepatocellular carcinoma (HCC) pathogenesis. Therefore, in this study, we aimed to unveil the detailed molecular mechanism of TRIM55 and identify the potential target for lung adenocarcinoma patients. Surgical samples and lung cancer cell lines were collected to detect the TRIM55 expression for patients with or without lymph node/distal organ metastasis. Cellular functional assays including transwell assay, wound healing assay, cellular survivability assay, etc. as well as ubiquitination assay were performed to evaluate the impact of TRIM55/Snail1 regulatory network via the UPP pathway on lung cancer tumor cell migration and chemo-resistance. Lung cancer tissues and tumor cell lines exhibited significantly lower levels of TRIM55 expression. Functional study further indicated that TRIM55 inhibited chemo-resistance, migration, and cancer stem-cell like phenotype of tumor cells. Further detailed molecular experiments indicated that TRIM55 promoted degradation of Snail1 via the UPP pathway, which played an interesting role in the regulation of cancer cell malignancy. This study provided novel theory that TRIM55 acted as a potential tumor suppressor by inhibition of tumor cell malignancy through enhancement of Snail1 degradation via the UPP pathway. Our research will inspire further exploration on TRIM55 to promote therapeutic effects for lung adenocarcinoma patients.

Pembrolizumab combined with paclitaxel and platinum as induction therapy for locally advanced esophageal squamous cell carcinoma: a retrospective, single-center, three-arm study.

Background: Pembrolizumab has been shown to have a powerful benefit for locally advanced or metastatic esophageal cancer. The aim of present study was to evaluate the efficacy and safety of pembrolizumab combined with neoadjuvant chemotherapy for locally advanced and potentially resectable esophageal squamous cell carcinoma (ESCC). Methods: Patients diagnosed with clinical stage III-IV ESCC and have a chance of resectability at Fujian Provincial Hospital were included into this study. Patients received pembrolizumab in combination with paclitaxel and nedaplatin as induction therapy once every 3 weeks in the first stage. After 4 cycles of pembrolizumab therapy, the patients then chose to undergo radical surgery (group A), radical radiotherapy (group B), or neither (group C). In the third stage, maintenance treatment with pembrolizumab was administered to all patients. Results: A total of 39 patients (33 male and 6 female) with a median age of 64 years were included. After immune response evaluation in the first stage, 34 (87.2%) patients achieved immune partial response (iPR), and 5 (12.8%) patients achieved immune stable disease (iSD). The objective response rate (ORR) was 87.2% (34/39), and the disease control rate (DCR) was 100%. In the second stage, 22 patients received radical surgery, all of whom achieved R0 resection. The major pathological response (MPR) rate was 68.2% (15/22), and the pathological complete response (pCR) rate was 45.5% (10/22). Of the patients, 9 chose radiotherapy as the radical therapeutic method and 8 chose not to undergo any radical therapy. The median period of pembrolizumab therapy was 8 cycles (4-22 cycles). The median follow-up time was 14 months (3-34 months). The median overall survival and progression-free survival (PFS) times were not reached. The incidence of severe adverse events (AEs) (grade ≥3) was 15.4% (6/39). Conclusions: Pembrolizumab combined with paclitaxel and platinum for locally advanced and potentially resectable ESCC has a high ORR, high surgical conversion, MPR, pCR, and R0 resection rates, and tolerable AEs. Also, pembrolizumab could provide good benefits in sequential treatment with radical radiotherapy or maintenance therapy.

Two cases of non-small cell lung cancer patients with somatic or germline EGFR R776H mutation.

The development of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) has revolutionized the treatment for non-small cell lung cancer (NSCLC). Comprehensive genomic profiling for NSCLC enables clinicians to identify more uncommon genetic alterations in EGFR. It remains unclear whether patients with certain rare EGFR mutations can benefit from EGFR inhibitors. On the other hand, emerging evidence has also showed the involvement of inherited factors in lung cancer development. However, only few germline EGFR mutations have been reported, and their association with NSCLC familial risk remains ambiguous. Here, we report two cases of NSCLCs with uncommon EGFR mutation R776H. One patient carrying somatic EGFR R776H and L861Q was treated with afatinib and achieved a durable response. The other patient harbored a germline EGFR R776H and her son inherited the same germline R776H mutation whose CT examination showed multiple ground-glass nodules in both lungs requiring further follow-up and diagnosis. Our study demonstrated the responsiveness of compound R776H-L861Q mutations to afatinib. We also revealed the transmission of EGFR R776H and suggested it may confer the high susceptibility to lung cancer.

Evaluation of pembrolizumab for the treatment of advanced non-small cell lung cancer: a retrospective, single-centre, single-arm study.

BACKGROUND: Immune checkpoint inhibitors (ICIs) provided a paradigm shift for advanced non-small cell lung cancer (NSCLC) treatment and improved the clinical prognosis of such patients. Pembrolizumab is a humanized anti-programmed death cell protein 1 (PD-1) monoclonal antibody, approved for the treatment of patients with advanced or metastatic NSCLC. This article investigated and reported on the efficacy and safety of pembrolizumab in the treatment of advanced NSCLC in our center since 2019. METHODS: Patients with clinical stage III-IV NSCLC treated with pembrolizumab for ≥4 cycles were enrolled as participants in this study. Pembrolizumab was administered intravenously at a dose of 2 mg/kg every 3 weeks. A cycle was defined as 3 weeks of treatment. We assessed the efficacy and safety of pembrolizumab through the collection of researcher-assessed tumor response, survival, and safety data. RESULTS: A total of 24 patients were included in this study. The median follow-up time was 9 months (3-20 months) and the median period of pembrolizumab therapy was 7 cycles (4-21 cycles). The objective response rate (ORR) was 45.8% and disease control rate (DCR) was 70.8%. The median overall survival (OS) and progression-free survival (PFS) times were not reached. A total of 2 programmed death-ligand 1 (PD-L1)-negative participants were treated with pembrolizumab combined with chemotherapy and there was no significant progression during the follow-up period. During the follow-up period, 8 patients underwent surgery. The major pathological response (MPR) was 75% and pathological complete response (pCR) was 50%. A case that was preoperatively diagnosed with clinical stage IV achieved pCR after 6 cycles of pembrolizumab combined with chemotherapy. The incidence of adverse effects (AEs) was 83.3%, and 16.7% of these were serious AEs (grade ≥3), which was similar to the incidence reported in previous studies. CONCLUSIONS: This real-world data supports the use of pembrolizumab for advanced NSCLC, including those cases that are PD-L1 negative. More importantly, pembrolizumab immunotherapy can also provide the potential of local treatment for patients with advanced NSCLC, which has wide application prospects in the field of surgery.

CircMED13L_012 promotes lung adenocarcinoma progression by upregulation of MAPK8 mediated by miR-433-3p.

BACKGROUND: Metastasis and disease refractoriness remain as major challenges for non-small cell lung cancer (NSCLC) treatment and understanding the underlying molecular mechanisms is of scientific and clinical value. Therefore, in this study, we aimed to explore the effects of circMED13L_012 on the proliferation, migration, invasion and drug-resistance of NSCLC tumor cells. METHODS: In this study, we utilized clinical samples and NSCLC cell lines to explore the association between circMED13L_012 expressions and tumor cell metastasis and chemo resistance. CCK8 and transwell assay were conducted to explore the impact of circMED13_012 on NSCLC tumor proliferation and migrative capabilities. Dual-luciferase reporter gene assay was conducted to validate the circMED13L_012 interaction network. RESULTS: Our results demonstrated that circMED13L_012 exhibited significantly elevated average level in our clinical samples of NSCLC, compared with normal tissues. circMED13L_012 level was positively correlated with disease stage and metastatic status. Increased circMED13L_012 expression was associated with the enhanced migration, proliferation and chemo resistance of NSCLC cell lines. Further experiments indicated that circMED13L_012 promoted malignant behavior of NSCLC tumor cells by targeting MAPK8 through modulation miR-433-3p expression. CONCLUSIONS: Our study for the first time demonstrated that circMED13L_012-miR-433-3p-MAPK8 axis played important role for NSCLC pathogenesis, which could be potential therapeutic target for the development of future NSCLC treatment.

Metastatic sites as predictors in advanced NSCLC treated with PD-1 inhibitors: a systematic review and meta-analysis.

BACKGROUND: Programmed cell death protein 1 (PD-1) inhibitors are the first-line treatment for advanced non-small-cell lung cancer (NSCLC) patients. However, their efficacy in metastatic NSCLC patients remains controversial. AIM OF THE STUDY: The aim of our study was to evaluate the prognosis of advanced metastatic NSCLC patients treated with PD-1 inhibitors, and discuss the predictive effect of metastatic site on the long-term outcome. METHODS: The Embase, Ovid Medline, Cochrane Central Register of Controlled Trials, and PubMed databases were systematically screened up to February 10, 2020. Twenty-five eligible studies, involving 8,067 patients that assessed the impact of metastatic sites on survival outcome were incorporated in our study. Overall survival (OS) and progression-free survival (PFS) were described as hazard ratio (HR) with 95% confidence interval (CI). RESULTS: Among the advanced NSCLC patients, the median proportion of brain, liver, bone, and adrenal gland metastases were 21%, 17%, 35%, and 21%, respectively. Patients with metastases to the brain, liver, and bone had worse OS compared to patients without these metastases when treated with PD-1 inhibitors. Similarly, patients with metastasis to the brain and liver were more likely to progress when treated with PD-1 inhibitors. Besides, patients with multiple metastatic sites had worse PFS compared to patients with one metastatic site, while no significant difference was found in terms of OS. CONCLUSIONS: Based on the findings of our systematic review and meta-analysis, metastatic sites were independent predictors of the survival outcome for advanced NSCLC patients treated with PD-1 inhibitors.

MiR-26a-5p Serves as an Oncogenic MicroRNA in Non-Small Cell Lung Cancer by Targeting FAF1.

PURPOSE: Non-small cell lung cancer (NSCLC) accounts for approximately 80-85% of all lung cancers, with the FAS-associated factor 1 (FAF1) acting as a tumor suppressor. MicroRNAs (miRNAs) can influence cancer progression by targeting oncogenes or anti-oncogenes. In this study, we aimed to reveal the influence of miR-26a-5p on the regulation of FAF1 expression and NSCLC progression, with the motivation of identifying a potential therapeutic target for NSCLC treatment. METHODS: A dual-luciferase reporter assay was used to check for the direct targeting of FAF1 by miR-26a-3p. The miR-26a-5p inhibitor or FAF1 shRNA plasmid was transfected into A549 and H1299 cells to modulate FAF1 expression. Then, the effect of miR-26a-5p/FAF1 on cellular functions was investigated. MTT assay was used to evaluate cell viability. EdU proliferation assay and cell cycle assay were performed to analyze the effect of miR-26a-5p on cell replication and cell cycle. We used annexin V-FITC and PI to stain apoptotic cells, followed by flow cytometric analysis. Transwell and wound healing assays were performed to investigate metastasis. Moreover, the effect of miR-26a-5p/FAF1 on cancer progression was examined in vivo. Lastly, the underlying mechanism was uncovered using RT-qPCR, Western blotting, and TOP/FOP flash assay. RESULTS: miR-26a-5p was found to directly target FAF1 and downregulate its expression. Blocking miR-26a-5p inhibited the cell growth, migration, and invasion, but promoted cell apoptosis. In addition, this inhibited the growth of tumor in mice. FAF1 knockdown reversed the functions of miR-26a-5p. Further, miR-26a-5p/FAF1 was observed to play an important role in the Wnt signaling pathway, regulating the expression of genes such as AXIN, c-Myc, and cyclin-D1. CONCLUSION: Taken together, we show that miR-26a-5p functions as an oncogenic microRNA in NSCLC by targeting FAF1 and may serve as a potential target for NSCLC treatment.

E2F1-induced ferritin heavy chain 1 pseudogene 3 (FTH1P3) accelerates non-small cell lung cancer gefitinib resistance.

Long noncoding RNAs (lncRNAs) have been identified to be critical regulator for various human diseases and emerging evidence illustrate the essential function of lncRNAs in the non-small cell lung cancer (NSCLC). Here, our research team tried to identify the roles of lncRNA ferritin heavy chain 1 pseudogene 3 (FTH1P3) in the NSCLC, as well as its molecular mechanism. LncRNA microarray analysis revealed that ferritin heavy chain 1 pseudogene 3 (FTH1P3) was up-regulated in the gefitinib-resistant cells (PC9/GR). Clinically, lncRNA FTH1P3 high-expression was closely correlated with NSCLC patients' unfavorable prognosis. Gain and loss of functional experiments revealed that FTH1P3 promoted the proliferation and invasion of NSCLC cells in vitro, and FTH1P3 knockdown repressed the tumor growth in vivo. Mechanistically, transcription factor E2F1 accelerated the transcription of FTH1P3. RNA immunoprecipitation and chromatin immunoprecipitation experiments showed that FTH1P3 can recruit lysine-specific demethylase 1 (LSD1) and epigenetically repress the TIMP3, thereby accelerating the tumorigenesis of NSCLC. In summary, these findings suggest that FTH1P3 plays a critical role in the gefitinib resistance and progression of NSCLC, providing a potential novel prognostic marker for NSCLC.

Novel technique for lymphadenectomy along left recurrent laryngeal nerve during thoracoscopic esophagectomy.

BACKGROUND: In esophageal squamous carcinoma, lymphadenectomy along the left recurrent laryngeal nerve (RLN) is recommended owing to its highly metastatic potential. However, this procedure is difficult due to limited working space in the left upper mediastinum, and increases postoperative complications. AIM: To present a novel method for lymphadenectomy along the left RLN during thoracoscopic esophagectomy in the semi-prone position. METHODS: The fundamental concept of this novel method is to exfoliate a bilateral pedicled nerve flap, which is a two-dimensional membrane, which includes the left RLN, lymph nodes (LNs) along the left RLN, and tracheoesophageal vessels, by suspending the esophagus to the dorsal side and pushing the trachea to the ventral side (named "bilateral exposure method"). Then, the hollow-out method is performed to transform the two-dimensional membrane to a three-dimensional structure, in which the left RLN and tracheoesophageal vessels are easily distinguished and preserved during lymphadenectomy along the left RLN. This novel method was retrospectively evaluated in 116 consecutive patients with esophageal squamous carcinoma from August 2016 to February 2018. RESULTS: There were 58 patients in each group. No significant difference was found between the two groups in terms of age, gender, postoperative pneumonia, anastomotic fistula, and postoperative hospitalization. However, the number of dissected LNs along the left RLN in this novel method was significantly higher than that in the conventional method (4.17 ± 0.359 vs 2.93 ± 0.463, P = 0.0447). Moreover, the operative time and the rate of postoperative hoarseness in the novel method were significantly lower than those in the conventional method (306.0 ± 6.774 vs 335.2 ± 7.750, P = 0.0054; 4/58 vs 12/58, P = 0.0312). CONCLUSION: This novel method for lymphadenectomy along the left RLN during thoracoscopic esophagectomy in the semi-prone position is much safer and more effective.