Dramatic response to crizotinib through MET phosphorylation inhibition in rare TFG-MET fusion advanced squamous cell lung cancer.

With the widespread use of next-generation sequencing (NGS) for solid tumors, mesenchymal-to-epithelial transition factor (MET) rearrangement/fusion has been confirmed in multiple cancer types. MET amplification and MET exon 14 skipping mutations induce protein autophosphorylation; however, the pathogenic mechanism and drug sensitivity of MET fusion remain unclear. The following report describes the clinical case of a patient diagnosed with squamous lung cancer bearing a TFG-MET gene fusion. In vitro assays demonstrated MET phosphorylation and oncogenic capacity due to the TFG-MET rearrangement, both of which were inhibited by crizotinib treatment. The patient was treated with crizotinib, which resulted in sustained partial remission for more than 17 months. Collectively, cellular analyses and our case report emphasize the potential of MET fusion as a predictive biomarker for personalized target therapy for solid tumors.

High-dose furmonertinib combined with intraventricular chemotherapy as salvage therapy for leptomeningeal metastasis from EGFR exon 20 insertion-mutated lung cancer.

PURPOSE: The treatment of leptomeningeal metastasis (LM), a serious complication of advanced non-small cell lung cancer (NSCLC), presents challenges, particularly in patients with EGFR exon 20 insertion (ex20ins) mutations. METHODS: This study retrospectively analyzed data from 10 EGFR ex20ins-mutated NSCLC patients with LM admitted at our institution from May 2011 to June 2023. Circulating tumor DNA (ctDNA) from cerebrospinal fluid (CSF) and matched plasma samples was analyzed using next-generation sequencing. All patients received high-dose furmonertinib combined with intraventricular chemotherapy (IVC) as salvage therapy. Data on patient demographics, treatment efficacy, and safety outcomes were collected. RESULTS: The most common insertion mutation identified in this study was p.A767_V769dup (n = 4, 40%), followed by D770-N771insY (n = 2, 20%). Nine patients had EGFR ex20ins occurring in the EGFR loop region following the C-helix, whereas only one patient had an EGFR ex20ins (A763_Y764insFQEA) occurring in the C-helix of the tyrosine kinase domain. LM response assessment using the RANO-LM criteria revealed that 6 patients (60%, 95% CI 26.2-87.8%) achieved a response, 3 had stable disease, and 1 had progressive disease. The median progression-free survival and overall survival were estimated to be 6.5 months and 8.8 months, respectively. The most commonly reported treatment-related adverse events were rash (n = 7) and diarrhea (n = 7), with no treatment-related deaths occurring. CONCLUSIONS: The current study demonstrated that high-dose furmonertinib plus IVC as salvage treatment for patients with LM harboring EGFR ex20ins mutations had promising clinical benefits and a manageable safety profile.

A benchmarking framework for the accurate and cost-effective detection of clinically-relevant structural variants for cancer target identification and diagnosis.

BACKGROUND: Accurate clinical structural variant (SV) calling is essential for cancer target identification and diagnosis but has been historically challenging due to the lack of ground truth for clinical specimens. Meanwhile, reduced clinical-testing cost is the key to the widespread clinical utility. METHODS: We analyzed massive data from tumor samples of 476 patients and developed a computational framework for accurate and cost-effective detection of clinically-relevant SVs. In addition, standard materials and classical experiments including immunohistochemistry and/or fluorescence in situ hybridization were used to validate the developed computational framework. RESULTS: We systematically evaluated the common algorithms for SV detection and established an expert-reviewed SV call set of 1,303 tumor-specific SVs with high-evidence levels. Moreover, we developed a random-forest-based decision model to improve the true positive of SVs. To independently validate the tailored 'two-step' strategy, we utilized standard materials and classical experiments. The accuracy of the model was over 90% (92-99.78%) for all types of data. CONCLUSION: Our study provides a valuable resource and an actionable guide to improve cancer-specific SV detection accuracy and clinical applicability.

Case report: Rechallenge with EGFR-TKIs after immunotherapy in EGFR-mutated non-small cell lung cancer with leptomeningeal metastasis.

Rechallenge of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) after PD-1 blockade failure was an effective therapy for non-small cell lung cancer (NSCLC) patients with resistance to EGFR-TKIs. The third-generation TKIs, like osimertinib and furmonertinib, can reach higher concentration in the cerebrospinal fluid (CSF) than other TKIs, and exhibit a beneficial effect in NSCLC patients with leptomeningeal metastases (LM) harboring sensitive EGFR mutation. Here, we report that two-stage IV pulmonary adenocarcinoma patients with LM harboring an EGFR L858R mutation benefit from the third-generation EGFR-TKIs rechallenge after immune checkpoint inhibitor (ICI) and anti-angiogenic agent combination therapy. Complete response (CR) to partial response (PR) of central nervous system (CNS) response was achieved immediately after the administration of furmonertinib and osimertinib. We conducted next-generation sequencing (NGS) and IHC to elucidate the evolution of driver mutations and the immune microenvironment. In conclusion, these two cases might provide a therapeutic strategy for further clinical practice. More research was needed to elucidate the resistance mechanisms and improve current treatment strategies in EGFR-mutated patients with LM.

Genomic profiling of non-small cell lung cancer with the rare pulmonary lymphangitic carcinomatosis and clinical outcome of the exploratory anlotinib treatment.

Background: To evaluate the potential treatment for patients with non-small cell lung cancer (NSCLC) and rare malignant pulmonary lymphangitis carcinomatosis (PLC), our study provided a genomic profile and clinical outcome of this group of patients. Methods: We retrospectively reviewed patients with NSCLC who developed PLC. The genomic alterations, tumor mutation burden (TMB), and microsatellite instability (MSI) based on DNA-based next-generation sequencing were reviewed and compared in a Chinese population with lung adenocarcinomas (Chinese-LUAD cohort). Clinical outcomes after exploratory anlotinib treatment and factors influencing survival are summarized. Results: A total of 564 patients with stage IV NSCLC were reviewed, and 39 patients with PLC were included. Genomic profiling of 17 adenocarcinoma patients with PLC (PLC-LUAD cohort) revealed TP53, EGFR, and LRP1B as the three most frequently altered genes. EGFR was less mutated in PLC-LUAD than Chinese-LUAD cohort of 778 patients (35.3% vs. 60.9%, P = 0.043). BRIP1 was mutated more often in the PLC-LUAD cohort (11.8% vs. 1.8%, P= 0.043). Two patients presented with high tumor mutational burden (TMB-H, 10 mutations/MB). Combing alterations in the patient with squamous cell carcinoma, the most altered pathways of PLC included cell cycle/DNA damage, chromatin modification, the RTK/Ras/MAPK pathway and VEGF signaling changes. Fourteen of the participants received anlotinib treatment. The ORR and DCR were 57.1% and 92.9%, respectively. Patients achieved a median progression-free survival of 4.9 months and a median overall survival of 7 months. The adverse effects were manageable. In patients with adenocarcinoma, the mPFS (5.3 months vs. 2.6 months) and mOS (9.9 months vs. 4.5 months) were prolonged in patients receiving anlotinib treatment compared to those receiving other treatment strategies (P < 0.05). Conclusion: Patients with PLC in NSCLC demonstrated distinct genetic alterations. The results improve our understanding of the plausible genetic underpinnings of tumorigenesis in PLC and potential treatment strategies. Exploratory anlotinib treatment achieved considerable benefits and demonstrated manageable safety.

Case report: Almonertinib in combination with bevacizumab for leptomeningeal metastases from epidermal growth factor receptor-mutation non-small cell lung cancer: Case series.

Leptomeningeal metastasis (LM) is a lethal complication of advanced non-small cell lung cancer (NSCLC) with rapid deterioration and poor prognosis. It has no standard treatment for epidermal growth factor receptor mutation (EGFRm) NSCLC, and improving the clinical outcomes for patients with LM has become an urgent problem in clinical treatment. Both almonertinib and bevacizumab are capable of crossing the blood-brain barrier with comparable central nervous system effectiveness. To date, the almonertinib treatment in combination with bevacizumab in EGFRm NSCLC with LM has not been studied. We herein present five cases to further evaluate the effectiveness and tolerability of almonertinib in combination with bevacizumab for patients with EGFRm NSCLC and LM. For the first time, we report that almonertinib plus bevacizumab can not only effectively improve the neurological symptoms caused by LM but also prolong the survival time of patients with limited and controllable side effects, which provided a novel therapeutic approach for LM from EGFRm NSCLC.

A novel intergenic region ALK fusion is targetable by alectinib in a non-small cell lung cancer patient with brain metastasis.

Anaplastic lymphoma kinase ( ALK ) rearrangement defines a unique nonsmall cell lung cancer (NSCLC) molecular subtype, of which the patients could potentially benefit from anti- ALK therapies. So far, the outcomes of the canonical echinoderm microtubule-associated protein-like ( EML-ALK ) patients subjected to ALK inhibitors are well established. However, given the increasing complexity of ALK fusion partners, as detected by high-throughput sequencing, the responses of those with rare ALK fusion events remain to be explored. Here, we report a lung adenocarcinoma patient with brain metastasis harboring an ARHGAP5 downstream intergenic region ALK fusion, as detected by using DNA-based next-generation sequencing, who experienced a partial response to alectinib treatment. While whole- transcriptome RNA sequencing (RNA-seq) failed to identify potential ALK fusion transcripts, subsequent targeted deep RNA-seq revealed the expression of EML4-ALK transcripts in the tumor tissue. Given the increasing application of the ALK-tyrosine kinase inhibitors (TKIs), it is extremely crucial to define the patients who could be suitable for this treatment in clinic. The present case has provided supporting evidence that noncanonical ALK rearrangements on the genomic level are often functionally relevant and targetable by ALK-TKI, particularly in cases with sub-optimal quantity and quality for RNA validation.

Erratum: circRNA Mediates Silica-Induced Macrophage Activation Via HECTD1/ZC3H12A-Dependent Ubiquitination: Erratum.

[This corrects the article DOI: 10.7150/thno.21648.].

Sequence-dependent synergistic effect of aumolertinib-pemetrexed combined therapy on EGFR-mutant non-small-cell lung carcinoma with pre-clinical and clinical evidence.

BACKGROUND: Inevitably developed resistance of the third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) limited its clinical benefit on non-small cell lung cancer (NSCLC). Upfront combination therapy is promising to prevent this resistance. Compelling clinical evidence indicated the failure of third-generation EGFR TKIs combined with either immunotherapy or antiangiogenic agents. In comparison, combined treatment of third-generation EGFR TKIs and chemotherapy might be a favorable choice. Herein, we systematically analyzed and compared the effects of pemetrexed and a novel third-generation EGFR TKI aumolertinib combined in different sequences, subsequently revealed the potential mechanisms and proved the optimal combination schedule with clinical retrospective study. METHODS: Three combination schedules involving pemetrexed and aumolertinib in different sequences were developed. Their inhibition effects on cell proliferation and metastasis were firstly compared upon three human NSCLC cell lines in vitro, by cell counting kit-8, colony formation, wound healing and transwell assays respectively. Further evaluation in vivo was proceeded upon H1975 and HCC827 xenograft model. Gene and protein expression were detected by Q-PCR and western blot. Drug concentration was determined by LC-MS/MS. VEGF secretion was determined by ELISA. Tumor vessel was visualized by immunofluorescence. Lastly, a clinical retrospective study was raised with 65 patients' data. RESULTS: The combination of pemetrexed and aumolertinib exhibited a sequence-dependent and EGFR mutant-dependent synergistic effect in vitro and in vivo. Only treatment with aumolertinib following pemetrexed (P-A) exhibited synergistic effect with stronger anti-tumor growth and anti-metastasis ability than monotherapy and also other combination sequences. This synergism could exclusively be observed in H1975 and HCC827 but not A549. Pathway analysis showed that P-A significantly enhanced the suppression of EGFR pathway. In addition, our results intriguingly found an obvious reduction of VEGF secretion and the accompanying normalization of the intratumor vessel, consequently increasing intratumoral accumulation of pemetrexed in P-A group. Finally, the clinical retrospective study verified the synergistic effect of P-A combination by significantly superior tumor response than aumolertinib monotherapy. CONCLUSION: Aumolertinib-pemetrexed combined therapy is promising for EGFR mutant NSCLC but only in right administration sequence. P-A could become an advantageous combination strategy in clinical with synergistic inhibition of tumor growth and metastasis.

A missing piece of the puzzle in pulmonary fibrosis: anoikis resistance promotes fibroblast activation.

BACKGROUND: Pulmonary fibrosis initiates a pneumonic cascade that leads to fibroblast dysfunction characterized by excess proliferation. Anoikis is a physiological process that ensures tissue development and homeostasis. Researchers have not clearly determined whether disruption of anoikis is involved in pulmonary fibrosis. RESULTS: Here, we investigated the mechanism by which silica induces fibroblast activation via anoikis resistance and subsequent fibrosis. Anoikis of lung fibroblasts, alveolar epithelial cells and endothelial cells during the process of fibrosis was detected using CCK-8, western blot, cell count and flow cytometry (FCM) assays. Although the three cell types showed similar increases in proliferation, the expression of NTRK2, a marker of anoikis resistance, was upregulated specifically in fibroblasts, indicating the unique proliferation mechanism of fibroblasts in pulmonary fibrosis, which may be related to anoikis resistance. Furthermore, the CRISPR/Cas9 system was used to investigate the molecular mechanism of anoikis resistance; the SiO2-induced inflammatory response activated the MAPK/PI3K signaling pathway in lung fibroblasts and then induced the expression of the ZC3H4 protein, which specifically mediated anoikis resistance, followed by pulmonary fibrosis. CONCLUSIONS: The current study revealed a specific pattern of fibroblast proliferation, and strategies targeting anoikis resistance may inhibit the pathological process of pulmonary fibrosis. This result provides a new approach for treating pulmonary fibrosis and new insights into the potential application of ZC3H4 in the development of novel therapeutic strategies for mitigating pulmonary fibrosis.

The Combined Effects of Circular RNA Methylation Promote Pulmonary Fibrosis.

m6A (N6-methyladenosine) is the most common type of RNA methylation modification, mainly occurring on mRNA. Whether m6A-modified circular RNAs (circRNAs) are involved in pulmonary fibrosis in different settings remains unclear. Using an m6A-circRNA epitranscriptomic chip, candidate circRNAs were selected, among which hsa_circ_0000672 and hsa_circ_0005654 were specifically involved in SiO2-induced pulmonary fibrosis by targeting the same protein, eIF4A3, indicating that the m6A modification of these two circRNAs has a synergistic effect on fibroblast dysfunction induced by SiO2. A mechanistic study revealed that the m6A modification of circRNAs was mainly mediated by the methyltransferase METTL3. Furthermore, METTL3 promoted the activation, migration, and activity of pulmonary fibroblasts and participated in SiO2-induced pulmonary fibrosis via the circRNA m6A modification. m6A methylation of circRNAs mediates silica-induced fibrosis, enriching the understanding of circRNAs and uncovering a potential new target for treating fibrosis-related diseases.

LINC01001 Promotes Progression of Crizotinib-Resistant NSCLC by Modulating IGF2BP2/MYC Axis.

Background: Crizotinib is a microtubule-related protein-4-anaplastic lymphoma kinase (EML4-ALK) multi-target tyrosine kinase inhibitor applied in the treatment of ALK-rearranged NSCLC. However, the specific molecular mechanism underlying its therapeutic effect remains unclear. Therefore, the purpose of this research is to explore the mechanism by which crizotinib targets NSCLC with ALK-rearrangement, mainly whether it is related to LINC01001 in regulating NSCLC progression via IGF2BP2/MYC axis. Methods: RT-qPCR is conducted to evaluate the mRNA levels of LINC01001, IGF2BP2 and MYC in A549/R and H1299/R cells. CCK-8 and EdU assays are performed to assess the viability and proliferation of A549/R and H1299/R cells. Western blot is conducted to measure the levels of PCNA and Ki-67 proteins in A549/R and H1299/R cells. FACs and TUNEL are performed to detect apoptosis of A549/R and H1299/R cells. Immunohistochemical staining is performed to assess the levels of Ki67 in crizotinib-resistant NSCLC tissue. Bioinformatics analysis of multiple CLIP (crosslinking-immunoprecipitation) data found potential binding sites between LINC01001 and IGF2BP2, IGF2BP2 and MYC, that are confirmed by RIP assay and RNA pulldown assay. Results: Our findings illustrated that LINC01001 is highly expressed in crizotinib-resistant NSCLC cells and associated with poor overall survival of NSCLC patients. Inhibition of LINC01001 depresses crizotinib resistance of NSCLC cells. LINC01001 interacts with IGF2BP2, and inhibition of IGF2BP2 depresses crizotinib resistance of NSCLC cells. IGF2BP2 interacts with the mRNA of MYC, and LINC01001 overexpression increases crizotinib resistance of NSCLC via MYC. Conclusion: LINC01001 promotes the progression of crizotinib-resistant NSCLC by modulating the IGF2BP2/MYC axis. Our research clarifies the specific mechanism of crizotinib-resistance in NSCLC treatment.

Lung adenocarcinoma patients with KEAP1 mutation harboring low immune cell infiltration and low activity of immune environment.

BACKGROUND: Kelch-like ECH-associated protein 1 (KEAP1) has been identified as a cancer driver gene in lung adenocarcinoma (LUAD), and increased evidence has given us clues about the association of KEAP1 mutation and immune characteristics. We assessed the association between KEAP1 mutation and tumor microenvironment in LUAD systematically. METHODS: With the data collected from The Cancer Genome Atlas (TCGA), we evaluated the association of KEAP1 mutation with tumor infiltrating leukocytes (TILs), including dendritic cell, CD8 T cell, CD4 T cell, neutrophil, B cells, and macrophage. Expression differences of the markers of those immune cells were also measured. We further compared the expression of antigen presentation genes and chemokines and the enrichment score of immune-related pathways. RESULTS: KEAP1 mutation had significant association with lower TILs and cytotoxic T lymphocyte. Strikingly, almost all of antigen presentation genes and chemokine showed lower expression in KEAP1-mutated tumors. Moreover, most of immune-related pathways were less active in KEAP1-mutated tumors. As expected, KEAP1-wild type LUADs favored better overall survival after immunotherapy. Finally, one patient harboring KEAP1 mutation along with a lack of immune cells infiltration in tumor microenvironment failed to respond to checkpoint inhibitor despite high tumor mutational burden (TMB). CONCLUSIONS: KEAP1 mutation has a significant effect on the tumor immune milieu of LUAD and may play as a predictive biomarker of immunotherapy for LUAD patients.

Association of TP53 Mutations with Response to Anlotinib Treatment in Advanced Non-Small Cell Lung Cancer.

Multitargeted antiangiogenic drugs have demonstrated significant antitumor activity against a variety of solid tumors. Anlotinib, a novel oral multitargeted antiangiogenic tyrosine kinase inhibitor, was approved as a third-line treatment for advanced NSCLC in China. However, predictive biomarkers are currently insufficient and are urgently required. Herein, we report three pre-treated cases of advanced NSCLC with TP53 mutations, wherein these patients showed partial response to anlotinib. Moreover, the three patients have achieved a progression-free survival of 8, 6.5, and 5 months, respectively. The main toxicities were hypertension, hand-foot syndrome and fatigue. In conclusion, TP53 mutations may represent a biomarker for predicting salutary effects of anlotinib.

CircHECTD1 mediates pulmonary fibroblast activation via HECTD1.

BACKGROUND: Circular RNA (circRNA), a new class of noncoding RNA, has been shown to be important in silicosis due to its unique role as a transcription regulator or as a sponge of small RNA regulators. Here, the mechanisms underlying circHECTD1/HECTD1 in fibroblast activation and subsequent fibrosis induced by SiO2 were investigated. METHODS: Primary human pulmonary fibroblasts (HPF-a) were utilized, combined with quantitative real-time PCR (qRT-PCR) and fluorescence in situ hybridization (FISH) assays. LC3B-LV-RFP lentivirus was used to evaluate the role of autophagy. The CRISPR/Cas9 system was applied to specifically knock down HECTD1, combined with MTT, BrdU, and migration assays, to explore the functional changes induced by SiO2. RESULTS: After exposure to SiO2, the circHECTD1 level was decreased, which was associated with an increase in HECTD1 in HPF-a cells. SiO2-induced autophagy was reversed by either circHECTD1 overexpression or HECTD1 knockdown in HPF-a cells, with restored SiO2-induced fibroblast activation, proliferation, and migration via downstream autophagy. The lungs of mice exposed to SiO2 confirmed the upregulation of HECTD1 in pulmonary fibroblasts. CONCLUSIONS: Our data suggested a link between circHECTD1/HECTD1 and fibroblast activation with subsequent fibrosis induced by SiO2, providing novel insight into the potential of circHECTD1/HECTD1 to be a therapeutic target for silicosis.

Hypertension as a predictive biomarker in patients with advanced non-small-cell lung cancer treated with apatinib.

BACKGROUND: Hypertension (HTN) is a common adverse event of the vascular endothelial growth factor pathway inhibitor apatinib. This study was conducted to evaluate the association of apatinib-induced HTN with clinical outcomes in patients with advanced non-small-cell lung cancer (NSCLC). METHODS: We retrospectively analyzed 110 consecutive patients with advanced NSCLC who were treated with apatinib from August 2014 to January 2018. All patients were classified as normotensive or hypertensive based on blood pressure measurements after initiating therapy. Therapeutic response, progression-free survival (PFS), and overall survival (OS) were evaluated. Univariate and multivariate analyses were performed using the Cox proportional hazards method. RESULTS: A total of 46 patients (42%) were diagnosed with HTN. The median PFS for the hypertensive and normotensive groups were 5.6 months and 4.2 months, respectively (P=0.0027). The median OS times for the hypertensive and normotensive groups were 9.9 months and 7.8 months, respectively (P=0.005). Thirty percent of patients who experienced HTN showed partial response to apatinib as compared with 6.3% of non-hypertensive patients (P=0.002). HTN was independently associated with improved PFS and OS on both univariate and multivariate analyses. CONCLUSION: Apatinib-induced HTN may be an inexpensive, valid, and easily measurable biomarker for apatinib antitumor efficacy in patients with advanced NSCLC.

Clinical research on therapeutic effect of combined application of lobaplatin and irinotecan in treating recurrant small cell lung cancer.

To observe and analyze the therapeutic effect of combinated application of lobaplatin and irinotecan in treating recurrant small cell lung cancer. The 140 patients who were treated in our hospital for recurrant small cell lung cancer were selected as research objects. All selected patients were subjected to combined application of obaplatin and irinotecan, the total therapeutic effect was observed, and the adverse reactions occurring during treatment were recorded. Through observing the total treatment effective ratio of 140 patients recurrant small cell lung cancer, the number of complete remission cases, number of partial remission cases, number of stable disease cases, and number of disease progression cases were 40(28.57%), 28(20.00%), 30(21.43%), 42(30.00%), respectively, with total effective ratio of 48.57%. The average time to progression (TTP) was (4.5±0.8) months, average overall survival (OS) was (7.6±1.2) months. The toxic and adverse effects mainly included hematological toxicity and gastrointestinal adverse reaction, such as leukocyte reduction, neutrophil reduction, thrombocytopenia, decreased hemoglobin, nausea and vomiting, diarrhea. No toxicity-related death occurred. In treatment of patients with recurrant small cell lung cancer, the combined application of lobaplatin and irinotecan can achieve great results, which is a safe and reliable way of treatment.

circHECTD1 promotes the silica-induced pulmonary endothelial-mesenchymal transition via HECTD1.

Excessive proliferation and migration of fibroblasts contribute to pulmonary fibrosis in silicosis, and both epithelial cells and endothelial cells participate in the accumulation of fibroblasts via the epithelial-mesenchymal transition (EMT) and the endothelial-mesenchymal transition (EndMT), respectively. A mouse endothelial cell line (MML1) was exposed to silicon dioxide (SiO2, 50 µg/cm2), and immunofluorescence and western blot analyses were performed to evaluate levels of specific endothelial and mesenchymal markers and to elucidate the mechanisms by which SiO2 induces the EndMT. Functional changes were evaluated by analyzing cell migration and proliferation. The mRNA and circular RNA (circRNA) levels were measured using qPCR and fluorescent in situ hybridization (FISH). Lung tissue samples from both Tie2-GFP mice exposed to SiO2 and silicosis patients were applied to confirm the observations from in vitro experiments. Based on the results from the current study, SiO2 increased the expression of mesenchymal markers (type I collagen (COL1A1), type III collagen (COL3A1) and alpha smooth muscle actin (α-SMA/Acta2)) and decreased the expression of endothelial markers (vascular endothelial cadherin (VE-Cad/Cdh 5) and platelet endothelial cell adhesion molecule-1 (PECAM1)), indicating the occurrence of the EndMT in response to SiO2 exposure both in vivo and in vitro. SiO2 concomitantly increased circHECTD1 expression, which, in turn, inhibited HECTD1 protein expression. SiO2-induced increases in cell proliferation, migration, and changes in marker levels were restored by either a small interfering RNA (siRNA) targeting circHECTD1 or overexpression of HECTD1 via the CRISPR/Cas9 system, confirming the involvement of the circHECTD1/HECTD1 pathway in the EndMT. Moreover, tissue samples from SiO2-exposed mice and silicosis patients confirmed the EndMT and change in HECTD1 expression. Our findings reveal a potentially new function for the circHECTD1/HECTD1 pathway and suggest a possible mechanism of fibrosis in patients with pulmonary silicosis.

Apatinib as a third- or further- line treatment in patients with advanced NSCLC harboring wild-type EGFR.

OBJECTIVES: This study was conducted to evaluate the efficacy and safety of apatinib in advanced NSCLC patients with EGFR wild-type who have failed more than second-line chemotherapy. MATERIALS AND METHODS: We retrospectively analyzed patients with EGFR wild-type advanced NSCLC who were treated with apatinib from January 2014 to August 2016. Objective response rate (ORR), disease control rate (DCR), progression free survival (PFS), overall survival (OS), and adverse events (AEs) were reveiwed and evaluated. Univariate and multivariate analyses were performed to determine the prognostic factors. RESULTS: 36 patients were evaluable for safety and efficacy. 6 patients obtained partial response, and 21 showed stable disease. The ORR and DCR were 16.7% and 75%, respectively. The median PFS and OS were 4.5 months and 8.2 months, respectively. Prognostic variable for a longer OS was good performance status (p = 0.015). Most adverse reactions were mild or moderate. CONCLUSIONS: Apatinib should be recommended as a third- or further- line therapy in advanced NSCLC patients with EGFR wild-type due to its better efficacy and tolerable toxicity.

circRNA Mediates Silica-Induced Macrophage Activation Via HECTD1/ZC3H12A-Dependent Ubiquitination.

Rationale: Phagocytosis of silicon dioxide (SiO2) into lung cells causes an inflammatory cascade that results in fibroblast proliferation and migration, followed by fibrosis. Circular RNAs (circRNAs) are a subclass of non-coding RNAs detected within mammalian cells; however, researchers have not determined whether circRNAs are involved in the pathophysiological process of silicosis. The upstream molecular mechanisms and functional effects on cell apoptosis, proliferation and migration were investigated to elucidate the role of circRNAs in SiO2-induced inflammation in pulmonary macrophages. Methods: Primary cultures of alveolar macrophages from healthy donors and patients as well as the RAW264.7 macrophage cell line were used to explore the functions of circHECTD1 (HECT domain E3 ubiquitin protein ligase 1) in macrophage activation. Results: The results of the experiments indicated that 1) SiO2 concomitantly decreased circHECTD1 levels and increased HECTD1 protein expression; 2) circHECTD1 and HECTD1 were involved in SiO2-induced macrophage activation via ubiquitination; and 3) SiO2-activated macrophages promoted fibroblast proliferation and migration via the circHECTD1/HECTD1 pathway. Tissue samples from silicosis patients confirmed the upregulation of HECTD1. Conclusions: Our study elucidated a link between SiO2-induced macrophage activation and the circHECTD1/HECTD1 pathway, thereby providing new insight into the potential use of HECTD1 in the development of novel therapeutic strategies for treating silicosis.