Growth Factor Receptor Tyrosine Kinase Research Articles

Lazertinib in EGFR-Variant Non–Small Cell Lung Cancer With CNS Failure to Prior EGFR Tyrosine Kinase Inhibitors

EGFR-variant non-small cell lung cancer (NSCLC) is associated with a high rate of central nervous system (CNS) metastases, even with treatment with first-generation or second-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). To investigate CNS activity with lazertinib, a third-generation EGFR TKI. This multicenter single-arm, phase 2 nonrandomized controlled trial was conducted in South Korea and included patients with EGFR-variant NSCLC who had asymptomatic or mildly symptomatic brain metastases after unsuccessful treatment with first-generation or second-generation EGFR TKIs. Data were collected from June 2021 to April 2022, with a data cutoff date of December 15, 2022. Lazertinib, 240 mg, once daily. The primary end point was intracranial objective response rate (iORR) in the evaluable population according to the Response Evaluation Criteria in Solid Tumours version 1.1 assessed by the investigators. Secondary end points included intracranial progression-free survival (iPFS) and iORR in patients with T790M-negative disease and isolated CNS progression as well as overall ORR, duration of response, intracranial duration of response, disease control rate, overall survival, cerebrospinal fluid penetration of lazertinib, and safety. Among 40 included patients, 25 (63%) were women, and the median (range) age was 63 (29-85) years. A total of 38 patients were evaluable for tumor response, including 12 patients with leptomeningeal metastases. At data cutoff, the median (range) follow-up was 13.6 (2.9-17.7) months. The iORR for the evaluable population was 55% (21 of 38; 95% CI, 38.3-71.4); for patients with T790M-positive disease, 80% (4 of 5; 95% CI, 28.4-99.5); for patients with T790M-negative disease, 43% (9 of 21; 95% CI, 21.8-66.0); and for patients with T790M-unknown disease, 67% (8 of 12; 95% CI, 34.9-90.1). The median iPFS was 15.8 months (95% CI, 15.2-not reached) for the evaluable population, 15.2 months (95% CI, 4.2-not reached) for the T790M-positive subgroup, 15.4 months (95% CI, 7.9-not reached) for the T790M-negative subgroup, and 18.0 months (95% CI, 3.9-not reached) for the T790M-unknown subgroup. The cerebrospinal fluid penetration rate of lazertinib was 46.2% (95% CI, 10.0-49.6), providing further support for its mechanism of intracranial response. Most adverse events were grade 1 or 2. In this study, lazertinib had substantial CNS activity, regardless of T790M status, against the progression of intracranial metastases with or without leptomeningeal metastases after unsuccessful treatment with first-generation or second-generation EGFR TKIs in patients with metastatic EGFR-variant NSCLC. These results suggest that using lazertinib instead of brain local treatment could be a potential strategy in patients with EGFR-variant NSCLC whose CNS metastases progressed after prior EGFR TKI treatment. ClinicalTrials.gov Identifier: NCT05326425.

Downregulation of Rad51 Expression and Activity Potentiates the Cytotoxic Effect of Osimertinib in Human Non-Small Cell Lung Cancer Cells.

Osimertinib (AZD9291) is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor that has shown significant clinical benefits in patients with EGFR-sensitizing mutations or the EGFR T790M mutation. The homologous recombination (HR) pathway is crucial for repairing DNA double-strand breaks (DSBs). Rad51 plays a central role in HR, facilitating the search for homology and promoting DNA strand exchange between homologous DNA molecules. Rad51 is overexpressed in numerous types of cancer cells. B02, a specific small molecule inhibitor of Rad51, inhibits the DNA strand exchange activity of Rad51. Previous studies have indicated that B02 disrupted Rad51 foci formation in response to DNA damage and inhibited DSBs repair in human cells and sensitized them to chemotherapeutic drugs in vitro and in vivo. However, the potential therapeutic effects of combining osimertinib with a Rad51 inhibitor are not well understood. The aim of this study was to elucidate whether the downregulation of Rad51 expression and activity can enhance the osimertinib-induced cytotoxicity in non-small cell lung cancer (NSCLC) cells. We used the MTS, trypan blue dye exclusion and colony-formation ability assay to determine whether osimertinib alone or in combination with B02 had cytotoxic effects on NSCLC cell lines. Real-time polymerase chain reaction was conducted to measure the amounts of Rad51 mRNA. The protein levels of phosphorylated AKT and Rad51 were determined by Western blot analysis. We found that osimertinib reduced Rad51 expression by inactivating AKT activity. Rad51 knockdown using small interfering RNA or AKT inactivation through the phosphatidylinositol 3-kinase inhibitor LY294002 or si-AKT RNA transfection enhanced the cytotoxic and growth inhibitory effects of osimertinib. In contrast, AKT-CA (a constitutively active form of AKT) vector-enforced expression could mitigate the cytotoxic and cell growth inhibitory effects of osimertinib. Furthermore, B02 significantly enhanced the cytotoxic and cell growth inhibitory effects of osimertinib in NSCLC cells. Compared to parental cells, the activation of AKT and Rad51 expression in osimertinib-resistant cells could not be significantly inhibited by osimertinib treatment. Moreover, the increased expression of Rad51 is associated with the resistance mechanism in osimertinib-resistant H1975 and A549 cells. Collectively, the downregulation of Rad51 expression and activity enhances the cytotoxic effect of osimertinib in human NSCLC cells.

Dual Inhibition of SYK and EGFR Overcomes Chemoresistance by Inhibiting CDC6 and Blocking DNA Replication.

Targeting multiple signaling pathways has been proposed as a strategy to overcome resistance to single-pathway inhibition in cancer therapy. A previous study in epithelial ovarian cancers identified hyperactivity of spleen tyrosine kinase (SYK) and epidermal growth factor receptor (EGFR), which mutually phosphorylate and activate each other. Given the potential for pharmacologic inhibition of both kinases with clinically available agents, this study aimed to assess the antitumor efficacy of both pharmacologic and genetic SYK and EGFR co-inhibition using a multifaceted approach to analyze the global phosphoproteome and chemoresistant ovarian cancer cell lines, patient-derived organoids, and xenograft models. Dual inhibition of SYK and EGFR in chemoresistant ovarian cancer cells elicited a highly synergistic antitumor effect. Notably, the combined inhibition strategy activated the DNA damage response, induced G1 cell cycle arrest, and promoted apoptosis. The phosphoproteomic analysis revealed that perturbation of SYK and EGFR signaling induced a significant reduction in both phosphorylated and total protein levels of cell division cycle 6 (CDC6), a crucial initiator of DNA replication. Together, this study offers preclinical evidence supporting dual inhibition of SYK and EGFR as a promising treatment for chemoresistant ovarian cancer that disrupts DNA synthesis by impairing formation of the prereplication complex. These findings warrant further clinical investigation to explore the potential of this combination therapy in overcoming drug resistance and improving patient outcomes.

Complete response in a lung adenocarcinoma with pleural metastases initially treated with gefitinib and switched to osimertinib after cerebral oligo-progression with unknown T790M mutation: a case report and review of literature

BackgroundFirst- and second-generation anti-epithelial growth factor receptor tyrosine kinase inhibitors have shown great efficacy in the treatment of advanced adenocarcinoma with epithelial growth factor receptor mutations, but this efficacy is limited by certain resistance mechanisms, in particular the T790M mutation, which must be screened before second-line treatment with osimertinib is indicated. The search for this mutation is sometimes difficult, especially in cases of intracranial relapse, through this case report we attempt to discuss the possibility of initiating treatment with osimertinib despite an unknown T790M mutation in such situation.Case reportWe present the case of a 70-year-old Moroccan male patient diagnosed with non-small cell lung carcinoma initially metastatic to the pleura with an epithelial growth factor receptor mutation who received gefitinib in first line with a complete response, he subsequently presented with cerebral oligo-progression with extra cranial stability. The patient was started on osimertinib with unknown T790M status, as it was impossible to perform a cerebral biopsy, the evolution was characterized by a partial response followed by stereotactic radiotherapy then a complete response for 2 years.ConclusionWe can discuss osimertinib as an option for patients with stage IV non-small cell lung cancer with brain oligo-progression on prior tyrosine kinase inhibitors and unknown T790M status, further studies are needed in this area.

Predicting Survival of Metastatic Clear Cell Renal Cell Cancer Treated with VEGFR-TKI-Based Sequential Therapy.

(1) Objective: To develop a clinically useful nomogram that may provide a more individualized and accurate estimation of cancer-specific survival (CSS) for patients with clear-cell (CC) metastatic renal cell carcinoma (mRCC) treated with nephrectomy and vascular endothelial growth factor receptor-tyrosine kinase inhibitor (VEGFR-TKI)-based sequential therapy. (2) Methods: A prospectively maintained database of 145 patients with mRCC treated between 2008 and 2018 was analyzed to predict the CSS of patients receiving sunitinib and second- and third-line therapies according to current standards of practice. A nomogram based on four independent clinical predictors (Eastern Cooperative Oncology Group status, International Metastatic RCC Database Consortium score, the Morphology, Attenuation, Size and Structure criteria and Response Evaluation Criteria in Solid Tumors response criteria) was calculated. The corresponding 1- to 10-year CSS probabilities were then determined from the nomogram. (3) Results: The median age was 60 years (95% CI 57.9-61.4). The disease was metastatic at diagnosis in 59 (40.7%), and 86 (59.3%) developed metastasis during follow-up. Patients were followed for a median 48 (IQR 72; 95% CI 56-75.7) months after first-line VEGFR-TKI initiation. The concordance probability estimator value for the nomogram is 0.778 ± 0.02 (mean ± SE). (4) Conclusions: A nomogram to predict CSS in patients with CC mRCC that incorporates patient status, clinical risk classification and response criteria to first-line VEGFR-TKI at 3 months is presented. This new tool may be useful to clinicians assessing the risk and prognosis of patients with mRCC.

Optimizing first-line TKI treatment efficacy in PD-L1-positive EGFR-mutated NSCLC: the impact of antiangiogenic agents.

In individuals receiving treatment with epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs), those exhibiting positive PD-L1 expression might experience reduced progression-free survival (PFS). However, the effects on overall survival (OS) and the determination of efficacious treatment approaches are still not well-defined. In our retrospective study, we examined data from 193 NSCLC patients with advanced EGFR mutations who received first-line TKI treatments, treated at two centers of Shaw Hospital in Zhejiang, China. This analysis covered a period from 1 January 2016 to 30 April 2023. Patients with PD-L1 positivity exhibited a markedly shorter average PFS (9.5months versus 17.8months, P < 0.001) and OS (44.4months versus 65.7months, P = 0.016) relative to those without PD-L1 expression. This difference in both PFS and OS remained statistically significant even after adjusting for multiple factors (P < 0.001 for PFS and P = 0.028 for OS). In the PD-L1-positive cohort, introducing combination antiangiogenic significantly extended both PFS (from 9.1 to 25.7months, P = 0.026) and OS (from 42 to 53.5months, P = 0.03). Post-first-line TKI therapy, 39.3% of PD-L1-positive patients and 54.5% of PD-L1-negative patients developed the T790M mutation (P = 0.212), with no notable difference in PFS from second-line TKI treatments between the groups. Additionally, subsequent combination therapy with immunotherapy markedly prolonged OS in the PD-L1-positive group. However, for PD-L1-negative patients, neither combination antiangiogenic therapy nor later-line immunotherapy demonstrated significant benefits in PFS or OS. For PD-L1-positive patients, combined antiangiogenic treatments and immunotherapy can significantly improve survival outcomes. In contrast, PD-L1-negative patients show less benefit from these therapies, highlighting the greater efficacy of these treatments in PD-L1-positive individuals.

TONSL promotes lung adenocarcinoma progression, immune escape and drug sensitivity.

The tonsoku-like DNA repair protein (TONSL) encoded by the TONSL gene, located on chromosome 8q24.3, is crucial for repairing DNA double-strand breaks through homologous recombination. However, TONSL overexpression in lung adenocarcinoma (LUAD) promotes tumor development, leading to a poor prognosis. TONSL was verified as a reliable prognostic marker for LUAD using bioinformatics, and clinical features related to LUAD prognosis were screened from the TCGA database to establish the relationship between risk factors and TONSL expression. In addition, TONSL expression in normal and LUAD tissues was verified using real-time quantitative polymerase chain reaction and immunohistochemistry. To elucidate the possible functions of TONSL, TONSL-related differentially expressed genes were screened, and functional enrichment analysis was performed. Subsequently, siRNA was used to knock down TONSL expression in lung cancer cells for cytobehavioral experiments. The effects of TONSL expression on tumor immune escape were analyzed using the ESTIMATE algorithm and tumor immune-infiltration analysis. In addition, the half-maximal inhibitory concentration of LUAD with varying TONSL expression levels in response to first-line chemotherapeutic drugs and epidermal growth factor receptor-tyrosine kinase inhibitors was analyzed for drug sensitivity. Up-regulation of TONSL in LUAD promotes the proliferation, migration, and invasion of lung cancer cells, thereby contributing to a poor prognosis. Furthermore, TONSL overexpression promotes immune escape and drug sensitivity in LUAD. TONSL serves as a reliable prognostic marker for LUAD, and its up-regulation is associated with increased immune escape and drug sensitivity. These findings suggest that TONSL holds potential as a novel therapeutic target for LUAD.

Abstract We011: The role of hsa-miR-9-5p in hypercontractility: insights from patients with hypertrophic cardiomyopathy

Background: Hypertrophic cardiomyopathy (HCM) is an inherited disease characterized by the thickening of the heart muscle. Mutations in contractile proteins, such as myosin binding protein C ( MYBPC3 ) and β-myosin heavy chain ( MYH7 ), account for over half of patients with familial HCM. HCM is the leading cause of sudden cardiac death among young adults and athletes, with these mutations potentially leading to hypercontractility and arrhythmias culminating in sudden cardiac death. MicroRNAs (miRNAs) are pivotal regulators of gene expression that may influence disease progression. Despite their potential significance, there is a scarcity of published data on miRNA expression in HCM. Induced pluripotent stem cells (iPSCs) have emerged as valuable tools for modeling various cardiovascular diseases, including HCM. However, the miRNA expression profiles associated with HCM remain largely unexplored within iPSC models. Investigating the differential expression of miRNAs in HCM patients offers a promising avenue to identify potential therapeutic targets for individuals affected by this condition. Methods: We performed an unbiased screen using a microarray (NanoString Technologies) that contained 798 miRNAs to identify differentially expressed miRNAs in induced pluripotent stem cell (iPSC)-CM and myocardial tissues derived from healthy donors and HCM patients with MYBPC3 and MYH7 mutations. Results: We identified 5 differentially expressed miRNAs that are significantly downregulated in both mutant MYBPC3 iPSC-CM and myocardial tissue (miR-9-5p, -4443, -367-3p, -302c-3p, and -129-2-3p) (p ≤ 0.05). In mutant MYH7 iPSC-CM and myocardial tissue, 3 miRNAs that were significantly downregulated (miR-9-5p, -151a-3p, -129-2-3p), and 1 was significantly upregulated (miR-331-5p) (p ≤ 0.05). KEGG pathway analysis of gene targets using miRTarBase and g:Profiler revealed that miR-9-5p regulates genes in the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor resistance pathway (p = 3.99x10 -9 ), which is involved in hypercontractility associated with HCM. Conclusion: This work represents the first description of miRNA expression patterns in iPSC-CMs derived from patients with HCM with additional validation from primary myocardial tissue, the current gold standard. We identified the miR-9-5p/EGFR tyrosine kinase inhibitor resistance axis as a potential therapeutic target responsible for mitigating the hypercontractile phenotype exhibited in HCM.

Outcomes in non-small cell lung cancer with uncommon epidermal growth factor receptor L858 substitutions under first-line epidermal growth factor receptor tyrosine kinase inhibitors: A large real-world cohort study.

Atypical L858R or other L858X mutations in the epidermal growth factor receptor (EGFR) gene, beyond the classical EGFRL858R mutation caused by c.2573 T > G, have been identified in non-small cell lung cancer (NSCLC), yet their genomic features and survival benefits with EGFR tyrosine kinase inhibitor (TKI) treatment have not been fully explored. We retrospectively enrolled 489 NSCLC patients with baseline tumor tissue/plasma samples carrying uncommon EGFRL858R (N = 124), EGFRL858Q/M (N = 17), or classical EGFRL858R mutations (N = 348). The comparison of molecular features was performed using treatment-naïve tumor tissues. Survival benefits and resistance mechanisms of first-line EGFR TKI treatment were studied in an advanced disease subcohort. NSCLCs harboring uncommon EGFRL858R had lower TP53 mutation prevalence (p = 0.04) and chromosome instability scores (p = 0.02) than those with classical EGFRL858R. Concomitant EGFRL861Q mutations were enriched in NSCLCs with EGFRL858Q/M (p < 0.01), with cooccurrence in those carrying EGFRL858M. Patients with uncommon EGFRL858R experienced improved progression-free survival (PFS) compared to those with classical EGFRL858R (median: 13.0 vs. 10.0 months, hazard ratio [HR]: 0.57, 95% confidence interval [CI]: 0.41-0.80). The association remained significant when adjusting for sex, age, histological subtype, TKI category, and anti-vascular therapy (HR: 0.55, 95% CI: 0.39-0.77). Furthermore, EGFRL858Q/M patients showed enhanced first-line PFS (vs. classical EGFRL858R, HR: 0.26, 95% CI: 0.10-0.67), potentially benefiting more from afatinib. Additionally, NSCLCs with uncommon EGFRL858R and classical EGFRL858R had similar resistance profiles to EGFR TKIs. In conclusion, NSCLCs carrying atypical EGFR L858 aberrations, which had fewer TP53 mutations and higher chromosome stability, exhibited improved PFS under first-line EGFR TKIs than those with the classical EGFRL858R.

Adverse Effects of Gefitinib on Skin and Colon in a Lung Cancer Mouse Model.

Gefitinib, an Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor (EGFR-TKI), frequently causes side effects when used to treat non-small cell lung cancer. The purpose of this experiment was to investigate the side effect of gefitinib on the skin and colon of mice. Male Balb/c nu-nu nude mice aged 4-5 weeks were used as xenograft tumor models, and gefitinib at 150 mg/kg and 225 mg/kg was started at 9 days after the xenograft tumor grew out. The mice's weights and tumor volumes were tracked concurrently, and the mouse skin adverse reactions and diarrhea were observed during the treatment. The animal tissues were subjected to biochemical and pathological evaluations after 14 days. Gefitinib effectively decreased the size and weight of transplanted tumors in nude mice, while also lowering body weight and raising indexes of the liver and spleen. Gefitinib could cause skin adverse reactions and diarrhea in mice. Further pathological investigation revealed tight junction- related markers in the mice's skin and colon to be reduced and macrophages and neutrophils to be increased after gefitinib treatment. The findings imply that gefitinib has negative effects on the skin and colon. Gefitinib- induced skin and colon adverse reactions in mice have been successfully modeled in this study.

The Efficacy and Safety of Apatinib and Anlotinib in Advanced Non-Small Cell Lung Cancer.

Anlotinib and apatinib, both vascular endothelial growth factor receptor-tyrosine kinase inhibitors (VEGFR-TKIs), are clinically established in the treatment of advanced non-small cell lung cancer (NSCLC) in China, with anlotinib emerging as a standard treatment strategy. This study was conducted to evaluate the efficacy and safety of apatinib and anlotinib, and to compare their differences in treating patients with advanced NSCLC. We retrospectively analyzed the data of patients with advanced NSCLC treated with apatinib or anlotinib at a hospital in Eastern China from January 2017 to December 2021. The primary endpoint was progression-free survival (PFS), while secondary endpoints included objective response rate (ORR), disease control rate (DCR), overall survival (OS), and safety profile. A total of 145 patients were included in this study. Median PFS (mPFS) was 3.53 months for the apatinib group and 5.3 months for the anlotinib group (HR = 0.59, 95% CI: 0.41-0.84; P = 0.004), and median OS (mOS) was 7.6 months versus 15.6 months (HR = 0.68, 95% CI: 0.46-1.00; P = 0.048), which all showed significant differences after adjusting for confounders (P < 0.05). Subgroup analysis revealed that the presence or absence of bone metastases significantly influenced PFS in both treatment groups. The ORR was 3.03% in the anlotinib group versus 10.13% in the apatinib group (P = 0.12), the DCR was 72.73% versus 51.90% (P = 0.21). No unanticipated adverse events (AEs) were observed. The incidence of grade 3-4 AEs was significantly higher in the apatinib group (31.65% vs 13.64%, P < 0.05). Anlotinib demonstrated greater efficacy and safety compared to apatinib in the treatment of advanced NSCLC, particularly in patients with bone metastases and EGFR(-).

Oral lichenoid drug eruption due to osimertinib for lung cancer.

Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR) are linked with side effects involving skin and mucosa. Herein, we present a unique case of oral lichenoid drug eruption (LDE) in a patient treated with osimertinib. A 75-year-old woman was diagnosed with metastatic EGFR-mutated lung adenocarcinoma, and started on osimertinib 80 mg PO daily. At 24 months of therapy, the patient developed a painful, red, and white striated oral lesion involving the left buccal mucosa and the adjacent buccal aspect of gingivae. Biopsy showed oral LDE. Causality assessment between osimertinib and the oral LDE via Naranjo Adverse Drug Reaction probability scale revealed a score of 5. Osimetinib discontinuation was not felt to be in the best interest of the patient. Therefore, diphenhydramine HCL mouthwash every 6 h PRN (before meals) was started. Spicy and hot foods were discontinued. At a four-week follow-up visit, the patient reported moderate improvement in her symptoms. Oral LDEs are considered premalignant lesions as they can transform into squamous cell carcinoma; therefore, regular follow-up is needed. Awareness of this potential side effect of osimertinib would also prevent unnecessary (and potentially costly) work-up and lead to its prompt diagnosis and treatment.

Synergistic antitumor activity of baicalein combined with almonertinib in almonertinib-resistant non-small cell lung cancer cells through the reactive oxygen species-mediated PI3K/Akt pathway.

Almonertinib is an important third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) exhibiting high selectivity to EGFR-sensitizing and T790M-resistant mutations. Almonertinib resistance is a major obstacle in clinical use. Baicalein possesses antitumor properties, but its mechanism of antitumor action against almonertinib-resistant non-small cell lung cancer (NSCLC) remains unelucidated. CCK-8 assay was used to examine the survival rate of H1975/AR and HCC827/AR cells following treatment for 24h with different concentrations of baicalein, almonertinib or their combination. The changes in colony formation ability, apoptosis, and intracellular reactive oxygen species (ROS) levels of the treated cells were analyzed using colony formation assay and flow cytometry. Western blotting was performed to detect the changes in protein expressions in the cells. The effects of pre-treatment with NAC on proliferation, apoptosis, and PI3K/Akt signaling pathway were observed in baicalein- and/or almonertinib-treated cells. A nude mouse model bearing subcutaneous HCC827/AR cell xenograft were treated with baicalein (20mg/kg) or almonertinib (15mg/kg), and the tumor volume and body mass changes was measured. Both baicalein and almonertinib represses the viability of HCC827/AR and H1975/AR cells in a concentration-dependent manner. Compared with baicalein or almonertinib alone, the combined application of the two drugs dramatically attenuates cell proliferation; triggers apoptosis; causes cleavage of Caspase-3, PARP, and Caspase-9; downregulates the protein expressions of p-PI3K and p-Akt; and significantly inhibits tumor growth in nude mice. Furthermore, baicalein combined with almonertinib results in massive accumulation of reactive oxygen species (ROS) and preincubation with N-acetyl-L-cysteine (ROS remover) prevents proliferation as well as inhibits apoptosis induction, with partial recovery of the decline of p-PI3K and p-Akt. The combination of baicalein and almonertinib can improve the antitumor activity in almonertinib-resistant NSCLC through the ROS-mediated PI3K/Akt pathway.

Evaluation of Cytotoxicity and Metabolic Profiling of Synechocystis sp. Extract Encapsulated in Nano-Liposomes and Nano-Niosomes Using LC-MS, Complemented by Molecular Docking Studies.

Liposomes and niosomes can be considered excellent drug delivery systems due to their ability to load all compounds, whether hydrophobic or hydrophilic. In addition, they can reduce the toxicity of the loaded drug without reducing its effectiveness. Synechocystis sp. is a unicellular, freshwater cyanobacteria strain that contains many bioactive compounds that qualify its use in industrial, pharmaceutical, and many other fields. This study investigated the potential of nano-liposomes (L) and nano-niosomes (N) for delivering Synechocystis sp. extract against cancer cell lines. Four different types of nanoparticles were prepared using a dry powder formulation and ethanol extract of Synechocystis sp. in both nanovesicles (N1 and N2, respectively) and liposomes (L1 and L2, respectively). Analysis of the formed vesicles using zeta analysis, SEM morphological analysis, and visual examination confirmed their stability and efficiency. L1 and L2 in this investigation had effective diameters of 419 and 847 nm, respectively, with PDI values of 0.24 and 0.27. Furthermore, the zeta potentials were found to range from -31.6 mV to -43.7 mV. Regarding N1 and N2, their effective diameters were 541 nm and 1051 nm, respectively, with PDI values of 0.31 and 0.35, and zeta potentials reported from -31.6 mV to -22.2 mV, respectively. Metabolic profiling tentatively identified 22 metabolites (1-22) from the ethanolic extract. Its effect against representative human cancers was studied in vitro, specifically against colon (Caco2), ovarian (OVCAR4), and breast (MCF7) cancer cell lines. The results showed the potential activities of the prepared N1, N2, L1, and L2 against the three cell lines, where L1 had cytotoxicity IC50 values of 19.56, 33.52, and 9.24 µg/mL compared to 26.27, 56.23, and 19.61 µg/mL for L2 against Caco2, OVCAR4, and MCF7, respectively. On the other hand, N1 exhibited IC50 values of 9.09, 11.42, and 2.38 µg/mL, while N2 showed values of 15.57, 18.17, and 35.31 µg/mL against Caco2, OVCAR4, and MCF7, respectively. Meanwhile, the formulations showed little effect on normal cell lines (FHC, OCE1, and MCF10a). All of the compounds were evaluated in silico against the epidermal growth factor receptor tyrosine kinase (EGFR). The molecular docking results showed that compound 21 (1-hexadecanoyl-2-(9Z-hexadecenoyl)-3-(6'-sulfo-alpha-D-quinovosyl)-sn-glycerol), followed by compounds 6 (Sulfoquinovosyl monoacylgycerol), 7 (3-Hydroxymyristic acid), 8 (Glycolipid PF2), 12 (Palmitoleic acid), and 19 (Glyceryl monostearate), showed the highest binding affinities. These compounds formed good hydrogen bond interactions with the key amino acid Lys721 as the co-crystallized ligand. These results suggest that nano-liposomes and nano-niosomes loaded with Synechocystis sp. extract hold promise for future cancer treatment development. Further research should focus on clinical trials, stability assessments, and pharmacological profiles to translate this approach into effective anticancer drugs.

Inhibition of DDR1 promotes ferroptosis and overcomes gefitinib resistance in non-small cell lung cancer

Gefitinib is an epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), which serves the critical pillar for the treatment of non-small cell lung cancer (NSCLC). However, the acquired resistance remains a challenge for its clinical application, for which, practical strategies to reverse gefitinib resistance in NSCLC are necessary. Ferroptosis, a programmed cell death driven by ferritin-dependent lipid peroxidation, involves in NSCLC progression and related chemoresistance. In our previous work, the self-synthesised EGFR inhibitor Yfq07 (N4, N6-disubstituted pyrimidine-4,6-diamine derivatives) displayed a considerable inhibitory effect on NSCLC both in vitro and in vivo. Herein, we observed that Yfq07 suppressed the proliferation of PC-9GR and HCC827GR cells, two gefitinib resistance NSCLC cell lines. Mechanically, Yfq07 inhibited the phosphorylation of the Discoidin Domain Receptor 1 (DDR1), a receptor tyrosine kinase (RTK) highly expressed in multiple cancers, accompanied by downregulated miR-3648 and upregulated SOCS2. Inhibition or knockdown of DDR1 suppressed the proliferation, migration, and invasion of gefitinib-resistant NSCLC cells, and on the other hand, also downregulated miR-3648 and promoted SOCS2 expression. More specifically, miR-3648 targeted the 3’UTR segment of SOCS2 mRNA and thus affecting the P-ERK signalling pathway to regulate the malignant behaviors of gefitinib-resistant NSCLC cells. Furthermore, Yfq07 also indirectly induced the ferroptosis of gefitinib-resistant NSCLC cells via SOCS2 triggered inhibition of xCT-GPX4 pathway. In conclusion, our study indicates that DDR1 inhibitor Yfq07 promotes ferroptosis and reverses gefitinib-resistance of NSCLC through DDR1-miR-3648-SOCS2 signalling pathway, which provides insights for targeted therapy of gefitinib-resistant NSCLC and drug developments targeting ferroptosis.

PSIP1 promotes gefitinib resistance in lung adenocarcinoma by inducing the expression of WASF3 and its downstream ITGB3/AKT signaling.

Gefitinib (GR), a representative drug of epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), is a key pillar in the treatment of lung adenocarcinoma (LUAD), but drug resistance is universal. Identifying the potential factors of drug resistance to GR is essential to treat patients with EGFR mutant LUAD. The GR-resistant LUAD cells were established and confirmed by MTT assay. The effects of PC4 and SRSF1 interacting protein 1 (PSIP1) on GR-resistant cell proliferation and apoptosis in vitro and in vivo were detected by colony formation, flow cytometry, tumor-bearing animal model, immunohistochemistry, and TUNEL staining. Western blotting and qPCR were used to determine the expression of relevant markers. The effect of PSIP1 on the promoter region of Wiskott-Aldrich syndrome protein family member 3 (WASF3) was detected by the dual-luciferase assay. The interaction between PSIP1 and RNA polymerase II was evaluated using ChIP-qPCR and Co-IP assays. PSIP1 was highly enriched in GR-resistant LUAD cells. Downregulation of PSIP1 expression significantly inhibited the proliferation of LUAD-resistant cells and promoted apoptosis. WASF3 was shown to have similar effects as PSIP1 in promoting drug resistance in LUAD cells. PSIP1 promoted the transcriptional activity of WASF3, which was achieved by increasing RNA polymerase II recruitment on the WASF3 promoter. Furthermore, PSIP1 positively regulated the expression of the pro-EGFR-TKI resistance factor integrin subunit beta 3 (ITGB3). Our work suggests that PSIP1 promotes resistance to GR in LUAD cells by inducing the expression of WASF3 and its downstream regulator ITGB3.

Discovery of a potent, selective, and orally available EGFR C797S mutant inhibitor (DS06652923) with in vivo antitumor activity

The C797S mutation is one of the major factors behind resistance to the third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). Herein, we describe the discovery of DS06652923, a novel, potent, and orally available EGFR-triple-mutant inhibitor. Through scaffold hopping from the previously reported nicotinamide derivative, a novel biaryl scaffold was obtained. The potency was successfully enhanced by the introduction of basic substituents based on analysis of the docking study results. In addition, the difluoromethoxy group on the pyrazole ring improved the kinase selectivity by inducing steric clash with the other kinases. The most optimized compound, DS06652923, achieved tumor regression in the Ba/F3 allograft model upon its oral administration.

Triple combination therapy comprising osimertinib, an AXL inhibitor, and an FGFR inhibitor improves the efficacy of EGFR-mutated non-small cell lung cancer

We previously reported that combined therapy with epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) osimertinib and AXL inhibitor ONO-7475 is effective in preventing the survival of drug-tolerant cells in high-AXL-expressing EGFR-mutated non-small cell lung cancer (NSCLC) cells. Nevertheless, certain residual cells are anticipated to eventually develop acquired resistance to this combination therapy. In this study, we attempted to establish a multidrug combination therapy from the first-line setting to overcome resistance to this combination therapy in high-AXL-expressing EGFR-mutated NSCLC. siRNA screening assay showed that fibroblast growth factor receptor 1 (FGFR1) knockdown induced pronounced inhibition of cell viability in the presence of the osimertinib–ONO-7475 combination, which activates FGFR1 by upregulating FGF2 via the c-Myc pathway. Cell-based assays showed that triple therapy with osimertinib, ONO-7475, and the FGFR inhibitor BGJ398 significantly increased apoptosis by increasing expression of proapoptotic factor Bim and reduced cell viability compared with that observed for the osimertinib–ONO-7475 therapy. Xenograft models showed that triple therapy considerably suppressed tumor regrowth. A novel therapeutic strategy of additional initial FGFR1 inhibition may be highly effective in suppressing the emergence of osimertinib- and ONO-7475-resistant cells.

Predictive value of serum magnesium levels for prognosis in patients with non-small cell lung cancer undergoing EGFR-TKI therapy.

The aim of this study is to assess the impact of serum magnesium (Mg) levels on prognostic outcomes in patients with non-small cell lung cancer (NSCLC) undergoing treatment with epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKI). A cohort comprising 91 patients with NSCLC with epidermal growth factor receptor mutations received EGFR-TKI therapy. Assessments of liver and kidney function and electrolyte levels were conducted before treatment initiation and after completing two cycles of EGFR-TKI therapy. Data on variables such as age, gender, presence of distant metastasis, smoking history, other therapeutic interventions, and the specific TKI used were collected for analysis. Cox regression analysis revealed that patients with higher Mg levels prior to EGFR-TKI therapy had significantly longer progression-free survival (PFS) and overall survival (OS). Elevated Mg levels remained predictive of PFS and OS after two cycles of EGFR-TKI therapy. Multiple regression analysis confirmed these findings. Additionally, it was observed that smokers might represent a unique population, demonstrating a correlation between OS and Mg levels. Our findings indicate that serum Mg level is a prognostic factor in patients with NSCLC undergoing EGFR-TKI therapy. This may provide new insights into the underlying mechanisms of EGFR-TKI therapy related to electrolyte balance.

Inorganic sulfides prevent osimertinib-induced mitochondrial dysfunction in human iPS cell-derived cardiomyocytes

Despite the widespread recognition of the global concern regarding the onset of cardiovascular diseases in a significant number of patients following cancer treatment, definitive strategies for prevention and treatment remain elusive. In this study, we established systems to evaluate the influence of anti-cancer drugs on the quality control of mitochondria, pivotal for energy metabolism, using human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). Osimertinib, an epidermal growth factor receptor tyrosine kinase inhibitor used for treatment in lung cancer, reportedly increases the risk of cardiovascular disease. However, its underlying mechanism is largely unknown. Here, we found that the treatment of hiPSC-CMs with osimertinib and doxorubicin, but not trastuzumab and cisplatin, revealed a concentration-dependent impairment of respiratory function accompanied by mitochondrial fission. We previously reported the significant role of sulfur metabolism in maintaining mitochondrial quality in the heart. Co-treatment with various inorganic sulfur donors (Na2S, Na2S2, Na2S3) alongside anti-cancer drugs demonstrated that Na2S attenuated the cardiotoxicity of osimertinib but not doxorubicin. Osimertinib decreased intracellular reduced sulfur levels, while Na2S treatment suppressed the sulfur leakage, suggesting its potential in mitigating osimertinib-induced cardiotoxicity. These results imply the prospect of inorganic sulfides, such as Na2S, as a seed for precision pharmacotherapy to alleviate osimertinib's cardiotoxic effects.