ZEB1 induces non-small cell lung cancer development by targeting microRNA-320a to increase the expression of RAD51AP1.

Lung cancer is the most prevalent cancer worldwide, with its mortality rate reported to be in millions annually; one of the two subtypes is non-small cell lung cancer (NSCLC). In this study, we investigated the interactions and expressions of zinc finger E-box binding homeobox 1 (ZEB1), microRNA-320a (miR-320a) and RAD51-associated protein 1 (RAD51AP1) in NSCLC tissues to determine the roles of ZEB1 in regulation of miR-320a and RAD51AP1 in the development and metastasis of NSCLC. First, the expression levels of miR-320a and ZEB1 were quantified in NSCLC tissues and cells. Transfection assay was conducted to identify the effects of miR-320a on the progression of NSCLC cells. The interaction of miR-320a with ZEB1 and RAD51AP1 was predicted and verified using dual-luciferase reporter gene assay and chromatin immunoprecipitation assay. Finally, subcutaneous xenograft tumors of 6-week mice and metastatic model tumors of 8-week mice were established to further explore the in vivo effect of miR-320a/ZEB1/RAD51AP1 on NSCLC. The findings revealed a lower expression of miR-320a in NSCLC tissues and cells, while this result was reversed regarding ZEB1 expression. ZEB1 suppressed miR-320a expression and upregulation of miR-320a resulted in the reduction of proliferation, invasion and metastasis rate of NSCLC cells, and promoted NSCLC cell apoptosis. ZEB1 promoted the expression of RAD51AP1 via inhibition of miR-320a, promoting tumor growth in vivo. ZEB1 transcriptionally inhibited the expression of miR-320a and upregulated the expression of RAD51AP1, thereby promoting metastasis in NSCLC.

Befotertinib for patients with pretreated EGFR T790M mutated locally advanced or metastatic NSCLC: Final overall survival results from a phase 2 trial.

BACKGROUND: In the initial analysis of a pivotal phase 2 single-arm study (NCT03861156), befotertinib (D-0316) showed clinical benefit with a manageable safety profile in pretreated patients with EGFR T790M mutated non-small cell lung cancer (NSCLC), including those with brain metastases. METHODS: Eligible patients received oral befotertinib of 50 mg (cohort A) or 75-100 mg (cohort B) once daily until disease progression, withdrawal of informed consent, or death. The primary endpoint for the initial analysis was objective response rate (ORR) assessed by an independent review committee. OS and safety were secondary endpoints. Herein, we present the final OS and safety data. RESULTS: A total of 176 patients in cohort A and 290 patients in cohort B were finally enrolled. At data cutoff (May 31, 2023), the median duration of follow-up was 47.9 months (95 % CI: 47.1-48.3) in cohort A and 36.7 months (35.9-37.9) in cohort B. The median OS was 23.9 months (95 % CI: 21.1-27.2) in cohort A and 31.5 months (26.8-35.3) in cohort B. The median OS for patients with and without brain metastasis in cohort A was 18.6 months (95 % CI: 14.9-26.3) and 26.4 months (95 % CI: 23.0-29.0), respectively. In cohort B, these data was 23.0 months (95 % CI: 18.6-29.1) and 35.5 months (95 % CI: 29.3-NE), respectively. The safety profile of befotertinib remained consistent with previous data. Grade 3 or higher treatment-emergent adverse events were 38.1 % in the cohort A and 50.3 % in the cohort B, and 22.2 % and 31.7 % were related to the study drug. CONCLUSION: Befotertinib demonstrated a more profound OS benefit compared to other 3rd-generation EGFR TKI, despite that cross trial data comparison should be interpreted with caution. The safety profile was manageable and consistent with previously report data in pretreated patients with confirmed T790M mutation-positive NSCLC.

Befotertinib (D-0316) versus icotinib as first-line therapy for patients with EGFR-mutated locally advanced or metastatic non-small-cell lung cancer: a multicentre, open-label, randomised phase 3 study.

BACKGROUND: Befotertinib (D-0316) is a novel, selective oral third-generation epidermal growth factor receptor (EGFR) tyrosine-kinase inhibitor. This phase 3 trial compared the efficacy and safety of befotertinib with icotinib as a first-line treatment for patients with EGFR mutation-positive locally advanced or metastatic non-small-cell lung cancer (NSCLC). METHODS: This study was a multicentre, open-label, randomised, controlled phase 3 study at 39 hospitals in China. Eligible patients were 18 years of age or older, had histologically confirmed locally advanced or metastatic stage IIIB, IIIC, or IV unresectable NSCLC, and had confirmed exon 19 deletions or exon 21 Leu858Arg mutation. Patients were randomly assigned (1:1) via an interactive web response system to receive either oral befotertinib (75-100 mg once daily) or oral icotinib (125 mg three times per day) in 21-day cycles until disease progression or withdrawal criteria were met. Randomisation was stratified by type of EGFR mutation, CNS metastasis status, and gender, and participants, investigators, and data analysts were not masked to treatment allocation. The primary endpoint was independent review committee (IRC)-assessed progression-free survival in the full analysis set, which comprised all randomly assigned patients. All patients who received at least one dose of the study drug were included in safety analyses. This study was registered with ClinicalTrials.gov, NCT04206072, and the overall survival follow-up is still in progress. FINDINGS: Between Dec 24, 2019, and Dec 18, 2020, 568 patients were screened, of whom 362 were randomly assigned to the befotertinib (n=182) or icotinib (n=180) group; all 362 patients were included in the full analysis set. Median follow-up was 20·7 months (IQR 10·2-23·5) in the befotertinib group and 19·4 months (10·3-23·5) in the icotinib group. Median IRC-assessed progression-free survival was 22·1 months (95% CI 17·9-not estimable) in the befotertinib group and 13·8 months (12·4-15·2) in the icotinib group (hazard ratio 0·49 [95% CI 0·36-0·68], p<0·0001). Grade 3 or higher treatment-related adverse events occurred in 55 (30%) of 182 patients in the befotertinib group and in 14 (8%) of 180 patients in the icotinib group. Treatment-related serious adverse events were reported in 37 (20%) patients in the befotertinib group and in five (3%) patients in the icotinib group. Two (1%) patients in the befotertinib group and one (1%) patient in the icotinib group died due to treatment-related adverse events. INTERPRETATION: Befotertinib demonstrated superior efficacy compared with icotinib in first-line treatment for patients with EGFR mutation-positive NSCLC. Although serious adverse events were more common in the befotertinib than the icotinib arm, the safety profile of befotertinib was manageable overall. FUNDING: Betta Pharmaceuticals (China). TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.

Efficacy and Safety of Befotertinib (D-0316) in Patients With EGFR T790M-Mutated NSCLC That Had Progressed After Prior EGFR Tyrosine Kinase Inhibitor Therapy: A Phase 2, Multicenter, Single-Arm, Open-Label Study.

INTRODUCTION: Befotertinib (D-0316) is a novel, third-generation EGFR tyrosine kinase inhibitor (TKI). This study evaluated befotertinib in patients with locally advanced or metastatic NSCLC who developed an EGFR T790M mutation after progression on first- or second-generation EGFR TKI therapy. METHODS: This was a single-arm, open-label, phase 2 study at 49 hospitals across mainland China. Patients with locally advanced or metastatic NSCLC harboring EGFR T790M mutations with disease progression after prior first- or second-generation EGFR TKI therapy received oral befotertinib of 50 mg (cohort A) or 75 to 100 mg (cohort B) once daily. The primary end point was objective response rate (ORR) assessed by an independent review committee in intention-to-treat population. This trial is registered with ClinicalTrials.gov, number NCT03861156. RESULTS: A total of 176 patients and 290 patients were included in cohorts A (50 mg) and B (75-100 mg), respectively. At data cutoff (August 15, 2021), independent review committee-assessed ORR was 67.6% (95% confidence interval [CI]: 61.9%-72.9%) in cohort B. The investigator-assessed ORR was 54.0% (95% CI: 46.3%-61.5%) in cohort A and 65.9% (95% CI: 60.1%-71.3%) in cohort B. The median investigator-assessed progression-free survival was 11.0 (95% CI: 9.6-12.5) months in cohort A and 12.5 (95% CI: 11.1-13.8) months in cohort B. The median independent review committee-assessed progression-free survival in cohort B was 16.6 (95% CI: 15.0-not evaluable [NE]) months. The intracranial ORR was 26.7% (95% CI: 7.8%-55.1%) in cohort A by investigator assessment, while 57.1% (95% CI: 34.0%-78.2%) and 55.9% (95% CI: 37.9%-72.8%) in cohort B by investigator and independent review committee assessment, respectively. The median investigator-assessed intracranial progression-free survival was 16.5 (95% CI: 8.6-NE) months in cohort A, while the median intracranial progression-free survival was not evaluable in cohort B due to immature data regardless of investigator or independent review committee assessment. and NE (95% CI: 13.8-NE) in cohort B. The overall survival was immature. Grade 3 or higher treatment-related adverse events and treatment-related serious adverse events occurred in 20.5% and 11.4% of patients in cohort A and in 29.3% and 10.0% of patients in cohort B, respectively. CONCLUSIONS: Befotertinib of 75 to 100 mg has satisfying efficacy and manageable toxicity in patients with locally advanced or metastatic NSCLC harboring T790M mutation with resistance to first- or second-generation EGFR TKIs. A phase 3 randomized trial is underway (NCT04206072).

[Over-expression of aquaporin 1 (AQP1) promotes cell proliferation and inhibits ß-catenin phosphorylation in human lung adenocarcinoma A549 cells].

Objective To investigate the effect of over-expression of aquaporin 1 (AQP1) gene on the proliferation of human lung adenocarcinoma A549 cells and its possible mechanism. Methods A lentiviral vector for over-expression of AQP1 was constructed, identified and used to infect A549 cells. Real-time quantitative PCR and Western blot analysis were performed to detect the expression of AQP1 mRNA and protein, respectively. In the AQP1-over-expressing A549 cells, MTT assay, clone formation assay and Western blot analysis were used to assess cell proliferation, cell clone forming ability, and ß-catenin phosphorylation level, respectively. Results The retroviral expression vector of AQP1 with a virus titer of (2.87±0.54)×108 IU/mL was obtained and A549 cells were infected with it to get a stable AQP1 over-expressing cell line. In this cell line, the AQP1 mRNA and protein levels were significantly raised, the cell proliferation ability was significantly improved, and the number of cell clones was significantly elevated. The total protein level of ß-catenin increased, but the phosphorylation of ß-catenin decreased significantly. Conclusion Over-expression of AQP1 promotes A549 cell proliferation and inhibits ß-catenin phosphorylation.

Silencing of RAD51AP1 suppresses epithelial-mesenchymal transition and metastasis in non-small cell lung cancer.

BACKGROUND: Non-small cell lung cancer (NSCLC) is a major cause of cancer-related mortality and is frequently accompanied by metastasis. The crucial roles of genes in lung cancer have attracted attention. Thus, this study aimed to investigate the effects of RAD51AP1 on the epithelial-mesenchymal transition (EMT) and metastasis of NSCLC. METHODS: The positive expression rate of the RAD51AP1 protein was examined. NSCLC cells were transfected with a series of plasmids to alter the expression of RAD51AP1 to clarify the influence of RAD51AP1 on EMT and metastasis in NSCLC, as well as NSCLC cell migration, invasion, apoptosis, proliferation, and cloning. An in vivo experiment was conducted to determine the oncogenicity of human NSCLC cells in nude mice. RESULTS: RAD51AP1 was highly expressed in NSCLC tissues. Furthermore, we found promotion of N-cadherin, vimentin, fibronectin, MMP-2, OPN, CD62, and TMP-2, but inhibition of E-cadherin, occludin, cytokeratin in the context of elevated RAD51AP1 expression. An in vivo experiment also confirmed that silencing of RAD51AP1 could inhibit NSCLC tumor formation and growth. CONCLUSION: Our results revealed that RAD51AP1 silencing suppressed the EMT and metastasis of NSCLC, thereby highlighting its potential as a promising novel target for NSCLC treatment.