NAT10-mediated upregulation of GAS5 facilitates immune cell infiltration in non-small cell lung cancer via the MYBBP1A-p53/IRF1/type I interferon signaling axis.

Interactions of tumor cells with immune cells in the tumor microenvironment play an important role during malignancy progression. We previously identified that GAS5 inhibited tumor development by suppressing proliferation of tumor cells in non-small cell lung cancer (NSCLC). Herein, we discovered a tumor-suppressing role for tumor cell-derived GAS5 in regulating tumor microenvironment. GAS5 positively coordinated with the infiltration of macrophages and T cells in NSCLC clinically, and overexpression of GAS5 promoted macrophages and T cells recruitment both in vitro and in vivo. Mechanistically, GAS5 stabilized p53 by directly binding to MYBBP1A and facilitating MYBBP1A-p53 interaction, and enhanced p53-mediated transcription of IRF1, which activated type I interferon signaling and increased the production of downstream CXCL10 and CCL5. We also found that activation of type I interferon signaling was associated with better immunotherapy efficacy in NSCLC. Furthermore, the stability of GAS5 was regulated by NAT10, the key enzyme responsible for N4-acetylcytidine (ac4C) modification, which bound to GAS5 and mediated its ac4C modification. Collectively, tumor cell-derived GAS5 could activate type I interferon signaling via the MYBBP1A-p53/IRF1 axis, promoting immune cell infiltration and potentially correlating with immunotherapy efficacy, which suppressed NSCLC progression. Our results suggested GAS5 as a promising predictive marker and potential therapeutic target for combination therapy in NSCLC. A schematic diagram demonstrating the regulatory effect of GAS5 on immune cell infiltration by activating type I interferon signaling via MYBBP1A-p53/IRF1 axis in non-small cell lung cancer. IFN, interferon.

Efficacy of immunotherapy in patients with oncogene-driven non-small-cell lung cancer: a systematic review and meta-analysis.

Background: Immunotherapy is an emerging antitumor therapy that can improve the survival of patients with advanced non-small-cell lung cancer (NSCLC). However, only about 20% of NSCLC patients can benefit from this treatment. At present, whether patients with driving gene-positive NSCLC can benefit from immunotherapy is one of the hot issues. Therefore, we conducted a meta-analysis to evaluate the efficacy of immunotherapy in patients with oncogene-driven NSCLC and concluded the efficacy of altered subtypes. Methods: A literature search was performed using PubMed, Web of Science, and Cochrane databases. The primary endpoints included the objective response rate (ORR), median progression-free survival (mPFS), and median overall survival (mOS) in patients with oncogene-driven NSCLC. Results: In all, 86 studies involving 4524 patients with oncogene-driven NSCLC were included in this meta-analysis. The pooled ORRs in clinical trials treated with monoimmunotherapy of EGFR, ALK, and KRAS alteration were 6%, 0%, and 23%, respectively. In retrospective studies, the pooled ORRs of EGFR, ALK, KRAS, BRAF, MET, HER2, RET, and ROS1 alteration were 8%, 3%, 28%, 24%, 23%, 14%, 7%, and 8%, respectively. Among them, the pooled ORRs of KRAS non-G12C mutation, KRAS G12C mutation, BRAF V600E mutation, BRAF non-V600E mutation, MET-exon 14 skipping, and MET-amplification were 33% 40%, 20%, 34%, 17%, and 60%, respectively. In addition, the pooled mPFS rates of EGFR, KRAS, MET, HER2, and RET alteration were 2.77, 3.24, 2.48, 2.31, and 2.68 months, while the pooled mOS rates of EGFR and KRAS alteration were 9.98 and 12.29 months, respectively. In prospective data concerning EGFR mutation, the pooled ORR and mPFS treated with chemo-immunotherapy (IC) reached 38% and 6.20 months, while 58% and 8.48 months with chemo-immunotherapy plus anti-angiogenesis therapy (ICA). Moreover, the pooled mPFS and mOS of monoimmunotherapy was 2.33 months and 12.43 months. Conclusions: EGFR-, ALK-, HER2-, RET-, and ROS1-altered NSCLC patients have poor reactivity to monoimmunotherapy but the efficacy of immune-based combined therapy is significantly improved. KRAS G12C mutation, BRAF non-V600E mutation, and MET amplification have better responses to immunotherapy, and more prospective studies are needed for further research.

Efficacy of immunotherapy in patients with oncogene-driven non-small cell lung cancer: a systematic review and meta analysis Immunotherapy is an emerging antitumor therapy that can improve the survival of patients with advanced NSCLC. However, only about 20% of NSCLC patients can benefit from this treatment. At present, whether patients with driving gene positive NSCLC can benefit from immunotherapy is one of the hot issues. Therefore, we conducted a meta-analysis to evaluate the efficacy of immunotherapy in patients with oncogene-driven NSCLC, and concluded the efficacy of altered subtypes. 86 studies involving 4524 patients with oncogene-driven NSCLC were included in this meta-analysis. The pooled ORR in clinical trials treated with monoimmunotherapy was of EGFR, ALK and KRAS alteration was 6%, 0%, and 23%, respectively. While in retrospective studies, the pooled ORR of EGFR, ALK, KRAS, BRAF, MET, HER2, RET and ROS1 alteration was 8%, 3%, 28%, 24%, 23%, 14%, 7% and 8%, respectively. Among them, the pooled ORR of KRAS non-G12C mutation, KRAS G12C mutation, BRAF V600E mutation, BRAF non-V600E mutation, MET-exon 14 skipping and MET-amplification was 33% 40%, 20%, 34%, 17% and 60%, respectively. Additionally, the pooled mPFS of EGFR, KRAS, MET, HER2 and RET alteration was 2.77, 3.24, 2.48, 2.31 and 2.68 months, while the pooled mOS of EGFR and KRAS alteration was 9.98 and 12.29 months. In prospective data concerning EGFR mutation, the pooled ORR and mPFS treated with chemo-immunotherapy (IC) was reached 38% and 6.20 months, while 58% and 8.48 months with chemo-immunotherapy plus anti-angiogenesis therapy (ICA). Moreover, the pooled mPFS and mOS of monoimmunotherapy was 2.33 months and 12.43 months. EGFR, ALK, HER2, RET and ROS1-altered NSCLC patients have poor reactivity to monoimmunotherapy, but the efficacy of immune-based combined therapy is significantly improved. KRAS G12C mutation, BRAF non-V600E mutation and MET amplification have better response to immunotherapy, and more prospective studies are needed for further research.

The safety and efficacy of anti-PD-1 inhibitor-based combinational therapy in non-small cell lung cancer patients with oncogenic alterations.

Background: The anti-programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) immunotherapy has been extensively used in patients with non-small cell lung cancer (NSCLC) in which the tumors are negative for oncogenic alterations. However, whether PD-1/PD-L1 blockade therapy could be applicable in patients harboring oncogenic mutations is largely unknown. Methods: In this retrospective study, we analyzed the safety and efficacy of anti-PD-1 inhibitor-based combinational therapy in a NSCLC cohort of 84 patients who harbored oncogenic alterations in epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), k-Ras, RET, HER2 and BRAF. The patients were followed up till disease progression or death. The adverse effects associated with the treatment were carefully evaluated and timely interrupted. Results: There were 50 patients harboring EGFR mutations, 17 patients with k-Ras mutation, 2 patients with ALK rearrangement, 6 patients with RET rearrangement, 6 patients with HER2 exon20 insertion and 3 patients with BRAF V600E mutation. About 58.8% of the k-Ras mutant patients responded to the combinational treatment. The median progression-free survival (mPFS) of the k-Ras cohort was 14 months, with the 12-month median overall survival (mOS) ratio and the 24-month OS ratio of 86.7% and 75.8%, respectively. Patients with EGFR exon21 L858R mutation or RET rearrangement tended to have a more favorable response, while patients harboring ALK rearrangement, HER2 exon20 insertion and BRAF V600E mutation did not respond well to anti-PD-1 inhibitor-based combinational therapy. The incidence of treatment-related toxicity was 52.3% and the most common immune-related adverse events (irAEs) were PD-1 inhibitors-related hypothyroidism and pneumonitis. The PD-L1 status and lung immune prognostic index (LIPI) could be used as biomarkers dictating therapeutic outcomes of the combinational therapy. Conclusions: The anti-PD-1 inhibitor-based combinational therapy elicited exciting anti-tumor efficacy and prolonged patient survival with manageable adverse effects in NSCLC patients harboring oncogenic alterations. The PD-L1 status and LIPI could be used as a biomarker predicting response to anti-PD-1 inhibitor-based combinational treatment in these patients.

Utilizing metagenomic next-generation sequencing for pathogen detection and diagnosis in lower respiratory tract infections in real-world clinical practice.

BACKGROUND: Infectious etiologies of lower respiratory tract infections (LRTIs) by the conventional microbiology tests (CMTs) can be challenging. Metagenomic next-generation sequencing (mNGS) has great potential in clinical use for its comprehensiveness in identifying pathogens, particularly those difficult-to-culture organisms. METHODS: We analyzed a total of 205 clinical samples from 201 patients with suspected LRTIs using mNGS in parallel with CMTs. mNGS results were used to guide treatment adjustments for patients who had negative CMT results. The efficacy of treatment was subsequently evaluated in these patients. RESULTS: mNGS-detected microorganisms in 91.7% (188/205) of the clinical samples, whereas CMTs demonstrated a lower detection rate, identifying microorganisms in only 37.6% (77/205) of samples. Compared to CMT results, mNGS exhibited a detection sensitivity of 93.5% and 95.4% in all 205 clinical samples and 180 bronchoalveolar lavage fluid (BALF) samples, respectively. A total of 114 patients (114/201; 56.7%) showed negative CMT results, among which 92 received treatment adjustments guided by their positive mNGS results. Notably, 67.4% (62/92) of patients demonstrated effective treatment, while 25% (23/92) experienced a stabilized condition. Subgroup analysis of cancer patients revealed that 41.9% (13/31) exhibited an effective response to treatment, and 35.5% (11/31) maintained a stable condition following medication adjustments guided by mNGS. CONCLUSION: mNGS demonstrated great potential in identifying microorganisms of clinical significance in LRTIs. The rapid turnaround time and reduced susceptibility to the impact of antimicrobial administration make mNGS a valuable supplementary tool for diagnosis and treatment decision-making for suspected LRTIs in clinical practice.

FBW7-mediated ubiquitination and destruction of PD-1 protein primes sensitivity to anti-PD-1 immunotherapy in non-small cell lung cancer.

BACKGROUND: Activation of the programmed cell death protein 1/programmed death-ligand 1 (PD-1/PD-L1) pathway has been extensively described as a pivotal mechanism to escape immune surveillance and elicits suppressive effect on antitumor immunity. Blockade of the PD-1/PD-L1 interaction by checkpoint inhibitors has been shown to result in tumor shrinkage and prolong patient survival. However, regulatory machinery for PD-1/PD-L1 expression is largely unknown. METHODS: We used bioinformatic tools and biochemical methods to investigate the significance of F-box and WD repeat domain containing 7 (FBW7) in regulating PD-1 protein stability. By generating a panel of FBW7 and PD-1 encoding plasmids, we expressed FBW7 and PD-1 or their mutants to performed immunoprecipitation and immunoblotting assays. The efficacy of cotargeting FBW7 to enhance antitumor immunity was evaluated in C57BL/6J mice. These laboratory findings were further validated in tumor samples obtained from patients with non-small cell lung cancer (NSCLC). RESULTS: We identified FBW7 as a E3 ubiquitin ligase for PD-1 protein, in which FBW7 promotes the K48-linked polyubiquitination of PD-1 protein at Lys233 residue. Cotargeting FBW7 accelerates PD-1 protein degradation and enhances antitumor immunity in vivo. Moreover, we demonstrated that cyclin-dependent kinase 1-mediated phosphorylation of Ser261 residue primes PD-1 protein nucleus translocation and binding with FBW7. Higher expression of FBW7 characterizes a 'hot' tumor microenvironment and confers more favorable responses to PD-1 blockade therapy. CONCLUSIONS: This study highlights the critical role of FBW7 in determining PD-1 protein stability. FBW7 ubiquitinates PD-1 in a phosphorylation-dependent manner, as a consequence, leading to PD-1 protein degradation and cytotoxic lymphocytes infiltrating the tumor microenvironment. Screening FBW7 status would predict clinical response to anti-PD-1 immunotherapy in patients with NSCLC, and targeting FBW7 is a promising strategy to enhance antitumor immunity.

Overexpression of 14-3-3ζ primes disease recurrence, metastasis and resistance to chemotherapy by inducing epithelial-mesenchymal transition in NSCLC.

The prognosis of non-small cell lung cancer (NSCLC) is disappointing because disease recurrence and distant metastasis inevitably occurred. The aim of the present study is to identify novel biomarkers predicting tumor recurrence and metastasis. The 14-3-3ζ protein has been extensively described as a tumor promoter in a panel of solid tumors, including NSCLC. However, there is a big gap regarding the knowledge between 14-3-3ζ and NSCLC recurrence. In this study, we found that overexpression of 14-3-3ζ was more frequent in NSCLC tumor tissues with tumor recurrence. By using scratch healing assay and transwell assay, we demonstrated that NSCLC cells with high expression of 14-3-3ζ gained increased motile and invasive capacity, whereas siRNA-mediated knockdown of endogenous 14-3-3ζ abrogated cancer cell dissemination. Intriguingly, we found that NSCLC cells underwent epithelial-mesenchymal transition (EMT) after the induction of 14-3-3ζ in vitro and in vivo. These findings could be readily recaptured in clinical setting since we showed that NSCLC tumor specimen with high expression of 14-3-3ζ revealed biological features of EMT. Overexpression of 14-3-3ζ also enhanced the phosphorylation of Akt and promoted the proliferation of NSCLC cell lines. In agreement with this notion, we reported that NSCLC cells with high expression of 14-3-3ζ became resistant to chemotherapy-induced apoptosis. These findings strongly suggested that 14-3-3ζ as a novel biomarker predicting risks of disease recurrence and screening 14-3-3ζ status may be a promising approach to select patients who experienced high risks of cancer recurrence and resistance to chemotherapy.

Host stimulator of interferon genes is essential for the efficacy of anti-programmed cell death protein 1 inhibitors in non-small cell lung cancer.

The stimulator of interferon genes (STING) pathway is important for anticancer immune responses. However, the relative contributions of host and tumour STING in anti-programmed cell death protein 1 (anti-PD-1) inhibitor responses in non-small cell lung cancer (NSCLC) are unknown. STING expression in tumour and blood was associated with anti-PD-1 therapy in NSCLC patients; Moreover, loss of PD-1 inhibitor therapeutic potency was demonstrated in STING KO (knock out) splenocytes and STING KO mice. STING knock-down in tumour cells had no effect. STING on CD8+ T cells and host cells, not tumour cells, correlated with clinical effect of anti-PD-1 therapy in NSCLC patients. Finally, adoptive transfer of CD8+ T cells restored PD-1 inhibitor anticancer effects. STING in host cells but not in tumour cells mediates anti-PD-1 inhibitor responses in cancer immunotherapy and could be used to select advantageous NSCLC patients from immunotherapy.

Immune checkpoint inhibitors alone vs immune checkpoint inhibitors-combined chemotherapy for NSCLC patients with high PD-L1 expression: a network meta-analysis.

BACKGROUND: We indirectly compared the effects of immune checkpoint inhibitors alone (ICI) and ICI-combined chemotherapy (chemo-ICI) in patients with non-small cell lung cancer who had high programmed death-ligand 1 (PD-L1) expression (defined as tumour proportion score ≥50% or TC3/IC3) through network meta-analyses. METHODS: Through literature searches, we shortlisted 22 randomised controlled trials encompassing 4289 patients, with objective response rate (ORR), progression-free survival (PFS), and overall survival (OS) set as the primary outcomes. The dichotomous data for ORR and hazard ratios (HRs) and their 95% confidence intervals (CIs) for OS and PFS were extracted. RESULTS: We found that chemo-ICI had significantly improved ORR (OR 1.7, 95% CI 1.1-2.5) and PFS (HR 0.59, 95% CI: 0.48-0.74) relative to ICI. Although no significant difference in OS was observed, the analyses revealed that the chemo-ICI patients tended to undergo fewer progression events than ICI patients (HR 0.82, 95% CI 0.6-1.1). In subgroup analysis, the non-squamous, PD-1 inhibitor and first-line treatment cohorts exhibited significant differences in ORR and PFS, but not in OS. However, in the squamous, PD-L1 inhibitor, and previously treated cohorts, PFS, OS and ORR were not different between chemo-ICI and ICI patients. CONCLUSIONS: In conclusion, for non-squamous NSCLC patients, accepting PD-1 as the first-line treatment may be a relatively better option.

F-circEA1 regulates cell proliferation and apoptosis through ALK downstream signaling pathway in non-small cell lung cancer.

Studies have confirmed that circular RNA (circRNA) has a stable closed structure, which plays an important role in the progression of tumors. Cancers with positive fusion genes can produce associated fusion circRNA (F-cirRNA). However, there are no reports concerning a role for F-circRNA of the echinoderm microtubule associated-protein like 4-anaplastic lymphoma kinase variant 1 (EML4-ALK1) in non-small cell lung cancer (NSCLC). Our study confirmed the existence of fusion circEA1 (F-circEA1) in NCI-H3122 cells (carrying the EML4-ALK1 gene), F-circEA1 was expressed both in the cytoplasm and nucleus as determined by fluorescence in situ hybridization (FISH) and Sanger sequencing. CCK8 and transwell assays showed that F-circEA1 was beneficial to cell proliferation, metastasis, and invasion. Overexpression of F-circEA1 can also promote cell proliferation, migration and invasion in A549 and SPCA1 cells (non-small cell lung cancer cell line not carrying the EML4-ALK1 gene). Interference with F-circEA1, induced cell cycle arrest and promoted apoptosis as determined by flow cytometry, and increased drug sensitivity to crizotinib in H3122 cells. F-circEA1 directly affected the expression of parental gene EML4-ALK1. Further research found that F-circEA1 can affect the downstream signaling pathway of ALK. In vivo, the growth rate of xenogeneic tumors was reduced and the protein expression level of EML4-ALK1 was significantly decreased in transplanted tumors measured by immunohistochemistry (IHC) after interference with F-circEA1. In conclusion, F-circEA1 can be considered as a proto-oncogene that regulates cell proliferation and apoptosis by affecting the expression of the parental gene EML4-ALK1 and its ALK downstream signaling pathway in non-small cell lung cancer.

Metastasis-associated fibroblasts: an emerging target for metastatic cancer.

Metastasis suggests a poor prognosis for cancer patients, and treatment strategies for metastatic cancer are still very limited. Numerous studies have shown that cancer-associated fibroblasts (CAFs), a large component of the tumor microenvironment, contribute to tumor metastasis. Stromal fibroblasts at metastatic sites are different from CAFs within primary tumors and can be termed metastasis-associated fibroblasts (MAFs), and they also make great contributions to the establishment of metastatic lesions and the therapeutic resistance of metastatic tumors. MAFs are capable of remodeling the extracellular matrix of metastatic tumors, modulating immune cells in the tumor microenvironment, promoting angiogenesis and enhancing malignant tumor phenotypes. Thus, MAFs can help establish premetastatic niches and mediate resistance to therapeutic strategies, including immunotherapy and antiangiogenic therapy. The results of preclinical studies suggest that targeting MAFs can alleviate the progression of metastatic cancer and mitigate therapeutic resistance, indicating that MAFs are a promising target for metastatic cancer. Here, we comprehensively summarize the existing evidence on MAFs and discuss their origins, generation, functions and related therapeutic strategies in an effort to provide a better understanding of MAFs and offer treatment perspectives for metastatic cancer.

Serum Exosomal miRNA Might Be a Novel Liquid Biopsy to Identify Leptomeningeal Metastasis in Non-Small Cell Lung Cancer.

PURPOSE: The survival time of patients with leptomeningeal metastasis (LM) of lung cancer is very short, and the clinical characteristics of LM are varied, making the clinical diagnosis difficult. At present, a positive CSF fluid (CSF) cytology result remains the gold standard for diagnosing LM in lung cancer; however, the process of collecting CSF is traumatic and far less convenient than blood collection. With the development in technology, an increasing number of studies prefer to use liquid biopsy to diagnose or predict the occurrence of the disease. Therefore, we aimed to explore whether serum exosomal miRNA can replace miRNA from CSF to identify or predict the occurrence of LM. PATIENTS AND METHODS: Herein, four pairs of serum and CSF samples were collected at four different time points from a patient with LM from non-small cell lung cancer (NSCLC). Serum and CSF exosomes were extracted. Western blot (CD63, TSG101) and electron microscope analyses were used to verify exosome extraction, after which exosomal miRNA sequencing was performed. Next, exosomal miRNA from serum and CSF samples from seven patients with LM and 30 patients without LM were collected for validation. RESULTS: Sequencing results of serum exosomal miRNA and CSF exosomal miRNA showed that there were 44 exosomal miRNAs stably co-expressed at four different time points. Then, three common miRNAs related to LM were found (hsa-miR-483-5p, hsa-miR-423-5p, and hsa-miR-342-5p). Subsequently, exosomal miRNA was extracted from serum and CSF samples from seven patients with LM and 30 patients without LM for verification, and the expression of these exosomal miRNA was detected. The results showed that miRNA-483-5p and miRNA-342-5p significantly differed in LM-/+ patients (P = 0.0142 and P = 0.0031, respectively), whereas miRNA-423-5p had no difference (P = 0.0921). Additionally, as the symptoms improved, the expression of these miRNAs decreased or remained stable. CONCLUSION: Serum exosomal miRNA (hsa-miR-483-5p, and hsa-miR-342-5p) may be involved in LM of lung cancer and may replace CSF to predict LM in NSCLC.

Targeting the ubiquitination/deubiquitination process to regulate immune checkpoint pathways.

The immune system initiates robust immune responses to defend against invading pathogens or tumor cells and protect the body from damage, thus acting as a fortress of the body. However, excessive responses cause detrimental effects, such as inflammation and autoimmune diseases. To balance the immune responses and maintain immune homeostasis, there are immune checkpoints to terminate overwhelmed immune responses. Pathogens and tumor cells can also exploit immune checkpoint pathways to suppress immune responses, thus escaping immune surveillance. As a consequence, therapeutic antibodies that target immune checkpoints have made great breakthroughs, in particular for cancer treatment. While the overall efficacy of immune checkpoint blockade (ICB) is unsatisfactory since only a small group of patients benefited from ICB treatment. Hence, there is a strong need to search for other targets that improve the efficacy of ICB. Ubiquitination is a highly conserved process which participates in numerous biological activities, including innate and adaptive immunity. A growing body of evidence emphasizes the importance of ubiquitination and its reverse process, deubiquitination, on the regulation of immune responses, providing the rational of simultaneous targeting of immune checkpoints and ubiquitination/deubiquitination pathways to enhance the therapeutic efficacy. Our review will summarize the latest findings of ubiquitination/deubiquitination pathways for anti-tumor immunity, and discuss therapeutic significance of targeting ubiquitination/deubiquitination pathways in the future of immunotherapy.

Treatment with convalescent plasma for COVID-19 patients in Wuhan, China.

The discovery of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the outbreak of coronavirus disease 2019 (COVID-19) are causing public health emergencies. A handful pieces of literature have summarized its clinical and radiologic features, whereas therapies for COVID-19 are rather limited. To evaluate the efficacy of convalescent plasma therapy in COVID-19 patients, we did this timely descriptive study. Six laboratory-confirmed COVID-19 patients were enrolled and received the transfusion of ABO-compatible convalescent plasma. The efficacy of this intervention was determined by the alleviation of symptoms, changes in radiologic abnormalities and laboratory tests. No obvious adverse effect observed during the treatment. Transfusion of convalescent plasma led to a resolution of ground-glass opacities and consolidation in patients #1, #2, #3, #4, and #6. In patients #1 and #5 who presented with SARS-CoV-2 in throat swab, convalescent plasma therapy elicited an elimination of the virus. Serologic analysis indicated an immediate increase in anti-SARS-CoV-2 antibody titers in patients #2 and #3, but not in patient #1. This study indicates that convalescent plasma therapy is effective and specific for COVID-19. This intervention has a special significance for eliminating SARS-CoV-2 and is believed to be a promising state-of-the-art therapy during COVID-19 pandemic crisis.

miR-24-3p/FGFR3 Signaling as a Novel Axis Is Involved in Epithelial-Mesenchymal Transition and Regulates Lung Adenocarcinoma Progression.

Our previous studies showed that Fibroblast growth factor receptor 3 (FGFR3) contributed to cell growth in lung cancer. However, the correlation between FGFR3 and tumor progression, coupled with the underlying mechanisms, are not fully understood. The clinical significance of FGFR3 was determined in two cohorts of clinical samples (n = 22, n = 78). A panel of biochemical assays and functional experiments was utilized to elucidate the underlying mechanisms and effects of FGFR3 and miR-24-3p on lung adenocarcinoma progression. Upregulated FGFR3 expression indicated an adverse prognosis for lung adenocarcinoma individuals and promoted metastatic potential of lung adenocarcinoma cells. Owing to the direct regulation towards FGFR3, miR-24-3p could interfere with the potential of proliferation, migration, and invasion in lung adenocarcinoma, following variations of EMT-related protein expression. As a significant marker of EMT, E-cadherin was negatively correlated with FGFR3, of which ectopic overexpression could neutralize the antitumour effects of miR-24-3p and reverse its regulatory effects on EMT markers. Taken together, these findings define a novel insight into the miR-24-3p/FGFR3 signaling axis in regulating lung adenocarcinoma progression and suggest that targeting the miR-24-3p/FGFR3 axis could be an effective and efficient way to prevent tumor progression.

Protein arginine methyltransferase 5 promotes lung cancer metastasis via the epigenetic regulation of miR-99 family/FGFR3 signaling.

Protein arginine methyltransferase 5 (PRMT5) functions as a tumor initiator to regulate several cancer progressions, such as proliferation and apoptosis, by catalyzing the symmetrical dimethylation (me2s) of arginine residues within targeted molecules. However, the exact role of PRMT5-mediated metastasis in lung cancer is not fully understood. Here, we illustrated its potential effects in lung cancer metastasis in vivo and vitro. PRMT5 was frequently overexpressed in lung tumors, and its expression was positively related to tumor stages, lymphatic metastasis and poor outcome. In this model, PRMT5 repressed the transcription of the miR-99 family by symmetrical dimethylation of histone H4R3, which increased FGFR3 expression and in turn activated Erk1/2 and Akt, leading to cell growth and metastasis in lung cancer. Furthermore, loss of PRMT5 exerted anti-metastasis effects on lung cancer progression by blocking histone-modification of miR-99 family. Overall, this study provides new insights into the PRMT5/miR-99 family/FGFR3 axis in regulating lung cancer progression and identifies PRMT5 as a promising prognostic biomarker and therapeutic target.

FBW7 loss promotes epithelial-to-mesenchymal transition in non-small cell lung cancer through the stabilization of Snail protein.

The E3 ubiquitin ligase F-box and WD repeat domain containing 7 (FBW7α) functions as a putative tumor suppressor in non-small cell lung cancer (NSCLC) due to its regulation of a set of oncogenic proteins associated with cell proliferation and mitosis. Increasing efforts have been focused on the understanding of FBW7 in determining cell cycle progression and apoptosis induction, however, the correlation between FBW7 and tumor metastasis is not fully understood. In this study, we reported a potential anti-metastatic effect of FBW7 in non-small cell lung cancer (NSCLC). In this model, FBW7 inhibited cancer cell metastasis primarily by inducing ubiquitination and proteolysis of the transcriptional factor Snail, which suppressed E-cadherin cell tight junction protein expression. Loss of FBW7 would stabilize the Snail protein, thus, inhibit E-cadherin expression and promote metastasis in vitro and in vivo. Moreover, Snail ubiquitination and degradation were also achieved by pharmacological approach, in which the FBW7 agonist oridonin treatment led to Snail proteolysis. Furthermore, FBW7 silencing stabilized Snail protein and induced epithelial-to mesenchymal transition (EMT), and acquisition of migration and invasion properties in NSCLC. Overall, our study provides new insights into the FBW7-Snail axis in regulating cell migration and invasion, and suggests that targeting FBW7 may be a potent approach to inhibit metastasis in NSCLC.

Activation of the Aryl Hydrocarbon Receptor Leads to Resistance to EGFR TKIs in Non-Small Cell Lung Cancer by Activating Src-mediated Bypass Signaling.

Purpose: The aryl hydrocarbon receptor (AhR) has been generally recognized as a ligand-activated transcriptional factor that responds to xenobiotic chemicals. Recent studies have suggested that the expression of AhR varies widely across different cancer types and cancer cell lines, but its significance in cancer treatment has yet to be clarified.Experimental Design: AhR expression in non-small cell lung cancer (NSCLC) was determined by Western blotting and IHC staining. In vitro and in vivo functional experiments were performed to determine the effect of AhR on sensitivity to targeted therapeutics. A panel of biochemical assays was used to elucidate the underlying mechanisms.Results: A high AhR protein level indicated an unfavorable prognosis for lung adenocarcinoma. Inhibition of AhR signaling sensitized EGFR tyrosine kinase inhibitors (TKIs) in NSCLC cells that express high level of endogenous AhR protein. Notably, activation of AhR by pharmacologic and molecular approaches rendered EGFR-mutant cells resistant to TKIs by restoring PI3K/Akt and MEK/Erk signaling through activation of Src. In addition, we found that AhR acts as a protein adaptor to mediate Jak2-Src interaction, which does not require the canonical transcriptional activity of AhR.Conclusions: Our results reveal a transcription-independent function of AhR and indicate that AhR may act as a protein adaptor that recruits kinases bypassing EGFR and drives resistance to TKIs. Accordingly, targeting Src would be a strategy to overcome resistance to EGFR TKIs in AhR-activated NSCLC. Clin Cancer Res; 24(5); 1227-39. ©2017 AACR.

Up-regulated basigin-2 in microglia induced by hypoxia promotes retinal angiogenesis.

Retinal microglia cells contribute to vascular angiogenesis and vasculopathy induced by relative hypoxia. However, its concrete molecular mechanisms in shaping retinal angiogenesis have not been elucidated. Basigin, being involved in tumour neovasculogenesis, is explored to exert positive effects on retinal angiogenesis induced by microglia. Therefore, we set out to investigate the expression of basigin using a well-characterized mouse model of oxygen-induced retinopathy, which recapitulated hypoxia-induced aberrant neovessel growth. Our results elucidate that basigin is overexpressed in microglia, which accumulating in retinal angiogenic sprouts. In vitro, conditioned media from microglia BV2 under hypoxia treatment increase migration and tube formation of retinal capillary endothelia cells, compared with media from normoxic condition. The angiogenic capacity of BV2 is inhibited after basigin knockdown by small interfering RNAs. A new molecular mechanism for high angiogenic capacity, whereby microglia cells release basigin via up-regulation of PI3K-AKT and IGF-1 pathway to induce angiogenesis is unveiled. Collectively, our results demonstrate that basigin from hypoxic microglia plays a pivotal pro-angiogenic role, providing new insights into microglia-promoting retinal angiogenesis.