EGFR-positive Cancer Research Articles

Exploring CAR-PBMCs: A Novel Strategy Against EGFR-Positive Tumor Cells

Background: Chimeric antigen receptor (CAR) T cell therapy has shown significant promise in treating hematological malignancies, yet its application in solid tumors, particularly those expressing the epidermal growth factor receptor (EGFR), remains limited. This study investigates the potential of CAR-engineered peripheral blood mononuclear cells (PBMCs) as a novel adoptive cell therapy against EGFR-positive cancers. Methods: Lentiviral transduction at an MOI of 50 was performed to generate specific anti-EGFR second generation CAR-effector cells. The transduced PBMCs were stimulated with cytokines and CD3/CD28 beads to enhance their proliferation and activation. Flow cytometric and real-time cell analysis were performed at various effector-to-target ratios to explore the cytotoxic potential of CAR-PBMCs. Results: CAR-PBMCs exhibited improved targeting and cytotoxicity against EGFR-positive cancer cell lines MDA-MB-468 and SK-BR-3, compared to untransduced controls, with unsignificant effects on allogeneic PBMCs. Conclusion: CAR-PBMCs hold considerable potential as a therapeutic strategy for EGFR-positive solid tumors, warranting further clinical investigation.

Smart Accumulating Dual-Targeting Lipid Envelopes Equipping Oncolytic Adenovirus for Enhancing Cancer Gene Therapeutic Efficacy.

Systemic delivery of oncolytic adenovirus (oAd) for cancer gene therapy must overcome several limitations such as rapid clearance from the blood, nonspecific accumulation in the liver, and insufficient delivery to the tumor tissues. In the present report, a tumor microenvironment-triggered artificial lipid envelope composed of a pH-responsive sulfamethazine-based polymer (PUSSM)-conjugated phospholipid (DOPE-HZ-PUSSM) and another lipid decorated with epidermal growth factor receptor (EGFR) targeting peptide (GE11) (GE11-DOPE) was utilized to encapsulate replication-incompetent Ad (dAd) or oAd coexpressing short-hairpin RNA (shRNA) against Wnt5 (shWnt5) and decorin (dAd/LP-GE-PS or oAd/LP-GE-PS, respectively). In vitro studies demonstrated that dAd/LP-GE-PS transduced breast cancer cells in a pH-responsive and EGFR-specific manner, showing a higher level of transduction than naked Ad under a mildly acidic pH of 6.0 in EGFR-positive cell lines. In vivo biodistribution analyses revealed that systemic administration of oAd/LP-GE-PS leads to a significantly higher level of intratumoral virion accumulation compared to naked oAd, oAd encapsulated in a liposome without PUSSM or EGFR targeting peptide moiety (oAd/LP), or oAd encapsulated in a liposome with EGFR targeting peptide alone (oAd/LP-GE) in an EGFR overexpressing MDA-MB-468 breast tumor xenograft model, showing that both pH sensitivity and EGFR targeting ability were integral to effective systemic delivery of oAd. Further, systemic administration of all liposomal oAd formulations (oAd/LP, oAd/LP-GE, and oAd/LP-GE-PS) showed significantly attenuated hepatic accumulation of the virus compared to naked oAd. Collectively, our findings demonstrated that pH-sensitive and EGFR-targeted liposomal systemic delivery of oAd can be a promising strategy to address the conventional limitations of oAd to effectively treat EGFR-positive cancer in a safe manner.

Strengthened binding affinity of bispecific antibody nanoplatforms improved the anti-tumor efficacy

Dual receptor targeting (DRT) strategies use bispecific antibodies to simultaneously target two distinct disease mediators and thereby overcome major escape mechanisms evident in mono-targeted therapy. DRT enhances the binding affinity between the ligand and receptors and the specific targeted delivery of nanoparticles (NPs) into cancer cells. In this study we developed anti-EGFR cetuximab (CTX) and Herceptin (HER) decorated poly(lactic-co-glycolic acid) (PLGA) NPs for the targeted delivery of docetaxel (DTX), which we call DRT-DTX-PLGA-NPs, and we quantified their binding affinity with EGFR and HER2 positive cancer cells.The binding affinity assay indicated that dual conjugation of CTX and HER on PLGA-NPsenhanced the binding affinity between the NPs and cells additively in terms of affinity and synergistically in terms of adhesion energy, compared with PLGA-NPs conjugated with CTX and HER. Furthermore, the DRT-DTX-PLGA-NPs exhibited higher cellular uptake and higher cancer cell cytotoxicity than the single receptor-targeted NPs. In SW480 xenograft mice, the DRT-DTX-PLGA-NPs were more concentrated and retained at the tumor site due to their enhanced binding affinity, and as a result, tumor volume and tumor weight were significantly inhibited compared with tumors treated with the single-ligand targeted NPs.Therefore, DRT-NPs have the potential to improve cancer therapy by providing high affinity between NPs and cells and improving selectivity compared with single-ligand-targeted NPs.

Abstract PO4-24-09: Grape seed extract inhibits EGFR signaling pathway as a main factor of tamoxifen resistant in hormone receptor positive breast cancer

Abstract Purpose Because more than 60% of breast cancers are hormone-receptor (HR) positive, endocrine therapy plays an important role. Tamoxifen is an antagonist of estrogen receptor-α and main treatment drug for HR-positive breast cancers. However, efficacy is not satisfactory because of the development of resistance. EGFR expression was associated with poor prognosis in HR-positive breast cancers. Loss of ER by EGFR activation induced tamoxifen resistance. And extracellular signal-regulated kinase (ERK) is another important factor for tamoxifen resistance. Activation of ERK signaling in breast cancer is not only associated with augmented tumor growth and metastasis but also with tamoxifen resistance. Therefore, the inhibition of ERK/EGFR signaling associated with tamoxifen resistance could improve the survival rate. Grape seed extract (GSE) is which contains a high content of flavonoid polyphenolic compounds. GSE is known to have various pharmacological effects, including antioxidant, anti-inflammatory, antitumor activity. In this study, we explored the activity of GSE in tamoxifen resistant breast cancer cells by inhibiting EGFR signaling pathway. Method We examined the suppressive effect of GSE on various signaling pathways. To confirm the pharmacological activity of GSE, we treated EGFR positive breast cancer cells with GSE. Levels of mRNA and protein expression were analyzed by real-time PCR and western blot. And cell proliferation and invasiveness were analyzed by the colony-forming assay and the Boyden chamber assay. Results 1. GSE down regulates EGFR and ERK in EGFR positive breast cancer cell line. The cells were treated with the indicated concentrations GSE for 48 hrs. The levels of p- and t-ERK and t-EGFR were measured through Western blotting. The levels of phosphorylated EGFR and ERK were decreased by GSE at the indicated doses for 48hrs. 2. EGF, a ligand of EGFR, upregulates the MMP-9 and GSE suppresses MMP-9. Matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) are upregulated in most cancers and play crucial roles in modulating invasion and metastasis. EGFR with its ligand epidermal growth factor (EGF) regulates Matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9). After treating EGFR positive breast cancer cells with EGF and TGF, MMP-9 levels were increased. However, MMP-9 level was decreased with GSE as indicated doses for 48hrs. Conclusion Taken together, GSE inhibited the ERK/EGFR and EGF/MMP-9 signaling pathway in EGFR positive breast cancer cells. Therefore, we propose the possibility of GSE as an effective adjuvant for tamoxifen resistant breast cancer. Citation Format: Seung Pil Jung, Eun-Shin Lee, Ji Young You, Jung Hwa Chun, Hyunyou Kim. Grape seed extract inhibits EGFR signaling pathway as a main factor of tamoxifen resistant in hormone receptor positive breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO4-24-09.

Antibody-dye Conjugates Targeting EGFR and HER2 for the Photoimmunotherapy of Bladder Cancer.

Although there are curative treatment options for non-muscle-invasive bladder cancer, the recurrence of this tumor is high. Therefore, novel targeted therapies are needed for the complete removal of bladder cancer cells in stages of localized disease, in order to avoid local recurrence, to spare bladder cancer patients from stressful and expensive treatment procedures and to increase their quality of life and life expectancy. This study tested a new approach for the photoimmunotherapy (PIT) of bladder cancer. We generated a cysteine modified recombinant version of the antibody cetuximab targeting the epidermal growth factor receptor (EGFR) on the surface of bladder cancer cells. Then, we coupled the novel photoactivatable phthalocyanine dye WB692-CB1 via a maleimide linker to the free cysteines of the antibody. PIT was performed by incubating bladder cancer cells with the antibody dye conjugate followed by irradiation with visible red light. The conjugate was able to induce specific cytotoxicity in EGFR-positive bladder cancer cells in a light dose-dependent manner. Enhanced cytotoxicity in RT112 bladder cancer cells was evoked by addition of a second antibody dye conjugate targeting HER2 or by repeated cycles of PIT. Our new antibody dye conjugate targeting EGFR-expressing bladder cancer cells is a promising candidate for the future PIT of bladder cancer patients.

A novel dihydroacridine derivative targets epidermal growth factor receptor-expressing cancer cells in vitro and in vivo.

Small molecules are considered a source of novel medicines targeting carcinogenic intracellular pathways including epidermal growth factor receptor (EGFR) signaling. The main goal of the study is to assess whether LHT-17-19 could be considered an effective target molecule against EGFR-expressing tumor cells in silico, in vitro, and in vivo. This was an in vivo, ex vivo, and in vivo experimental study. LHT-17-19 affinity to EGFR's kinase domain was assessed by the ligand's molecular docking. EGFR-expressing Hs746T human gastric cancer cell culture and patient-derived organoid (PDO) model of EGFR-positive breast cancer (BC) were used for in vitro assessment of the molecule anticancer property. IC50 and GI50 indexes were estimated using MTT- and MTS-based tests, respectively. Anticancer activity of LHT-17-19 against EGFR-expressing mutant lung carcinoma was studied on patient-derived xenograft (PDX) model established in 10 humanized BALB/c male mice. Continuous variables were presented as a mean ± standard deviation. Intergroup differences were assessed by two-way t-test. Kaplan-Meier's curves were used for survival analysis. High affinity of LHT-17-19 for the EGFR kinase domain with dG score -7.9 kcal/mol, EDoc-5.45 kcal/mol, and Ki 101.24 uM was due to intermolecular π-σ bonds formation and the ligand intramolecular transformation. LHT-17-19 induced anti-EGFR-expressing gastric cancer cells cytotoxicity with IC50 0.32 µM (95% confidence interval [CI] 0.11-0.54 µM). The derivative inhibited growth of EGFR-expressing BC PDO with GI50 16.25 µM (95% CI 4.44-28.04 µM). 2 mg/kg LHT-17-19 intravenously daily during 7 days inhibited PDX tumor growth and metastatic activity, prolonged animals' survival, and eliminated EGFR-mutant lung cancer cells from residual tumor's node. LHT-17-19 may be considered a molecular platform for further search of promising molecules, EGFR-expressing cancer cell inhibitors.

Abstract 4651: A macrocyclic kinase inhibitor overcomes the compound mutations that cause the resistance to all approved EGFR inhibitors in EGFR-positive lung cancer

Abstract EGFR mutant cancers account for 20-30 % of non-small cell lung cancers and show marked sensitivity to EGFR tyrosine kinase inhibitors (TKIs). However, the tumor almost inevitably relapses due to acquired resistance. To date, several EGFR-TKIs have been approved, and the third-generation EGFR-TKI, osimertinib, has been widely used both as first-line therapy and for patients with the EGFR-T790M mutation after 1st or 2nd generation EGFR-TKI therapy. However, the EGFR-T790M+C797S compound mutation confers resistance to all approved EGFR-TKIs. In our previous study, we experimentally demonstrated that brigatinib with anti-EGFR antibody was effective against osimertinib-resistant EGFR-C797S and EGFR-T790M+C797S mutants, and is currently undergoing clinical studies. However, the tumor would relapse because of the acquisition of additional resistance mutations. Here, we first demonstrated the binding mode of brigatinib to the EGFR-T790M/C797S mutant by crystal structure analysis and predicted brigatinib-resistant mutations through a cell-based assay, including N-ethyl-N-nitrosourea (ENU) mutagenesis. We found that clinically reported L718 and G796 compound mutations appeared, consistent with their proximity to the binding site of brigatinib, and brigatinib-resistant quadruple mutants, such as EGFR-activating mutation/T790M/C797S/L718M, were resistant to all clinically available EGFR-TKIs. BI-4020, a fourth-generation macrocyclic EGFR inhibitor plus anti-EGFR antibody, overcomes the quadruple and major EGFR-activating mutants in vitro and in vivo, but not the minor mutants such as L747P. Microsecond molecular dynamics simulations revealed the binding mode and affinity between BI-4020 and the EGFR mutants. This study identified potential therapeutic strategies using new-generation macrocyclic EGFR inhibitor to overcome the emerging resistance mutants. Citation Format: Ryohei Katayama, Ken Uchibori, Makoto Nishio, Naoya Fujita. A macrocyclic kinase inhibitor overcomes the compound mutations that cause the resistance to all approved EGFR inhibitors in EGFR-positive lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4651.

Distinction of ALK fusion gene- and EGFR mutation-positive lung cancer with tumor markers.

It is difficult to predict gene mutations individually based on clinical background alone. Tumor markers may help to predict each gene mutation. Identifying tumor markers that can predict gene mutation will facilitate timely genetic testing and intervention. We selected 134 cases of advanced or recurrent ALK-positive and 172 cases of advanced or recurrent EGFR-positive lung cancer from our clinical database. The cutoff values for the tumor markers were defined as 5.0 ng/mL or higher for carcinoembryonic antigen (CEA) and 3.5 ng/mL or higher for soluble fragment of cytokeratin 19 (CYFRA21-1) in accordance with the institutional standards. A positive CYFRA21-1:CEA ratio was defined as 0.7 or higher. The CEA-positivity rate was 49% for ALK-positive lung cancers and 73% for EGFR-positive lung cancers, which was significantly different (p < 0.001). The CYFRA21-1 positivity rate was significantly higher in ALK-positive lung cancer (36%) compared with EGFR-positive lung cancer (23%) (p = 0.034). The median CYFRA21-1:CEA ratio was 0.395 for the ALK group, which was significantly higher compared with 0.098 for the EGFR group (p < 0.001). These trends were similar when excluding histology other than adenocarcinoma. The median time-to-treatment failure (TTF) for initial tyrosine kinase inhibitor (TKI) therapy was 308 days for the high CYFRA21-1:CEA ratio group and 617 days for the low CYFRA21-1:CEA ratio group for ALK-positive lung cancer (p = 0.100). A higher proportion of patients with ALK-positive lung cancer were CYFRA21-1 positive and had higher CYFRA21-1:CEA ratios compared with EGFR-positive lung cancer patients.

A macrocyclic kinase inhibitor overcomes triple resistant mutations in EGFR-positive lung cancer

Brigatinib-based therapy was effective against osimertinib-resistant EGFR C797S mutants and is undergoing clinical studies. However, tumor relapse suggests additional resistance mutations might emerge. Here, we first demonstrated the binding mode of brigatinib to the EGFR-T790M/C797S mutant by crystal structure analysis and predicted brigatinib-resistant mutations through a cell-based assay including N-ethyl-N-nitrosourea (ENU) mutagenesis. We found that clinically reported L718 and G796 compound mutations appeared, consistent with their proximity to the binding site of brigatinib, and brigatinib-resistant quadruple mutants such as EGFR-activating mutation/T790M/C797S/L718M were resistant to all the clinically available EGFR-TKIs. BI-4020, a fourth-generation EGFR inhibitor with a macrocyclic structure, overcomes the quadruple and major EGFR-activating mutants but not the minor mutants, such as L747P or S768I. Molecular dynamics simulation revealed the binding mode and affinity between BI-4020 and EGFR mutants. This study identified potential therapeutic strategies using the new-generation macrocyclic EGFR inhibitor to overcome the emerging ultimate resistance mutants.

Effectiveness of 225Ac-Labeled Anti-EGFR Radioimmunoconjugate in EGFR-Positive Kirsten Rat Sarcoma Viral Oncogene and BRAF Mutant Colorectal Cancer Models.

Eighty percent of colorectal cancers (CRCs) overexpress epidermal growth factor receptor (EGFR). Kirsten rat sarcoma viral oncogene (KRAS) mutations are present in 40% of CRCs and drive de novo resistance to anti-EGFR drugs. BRAF oncogene is mutated in 7%-10% of CRCs, with even worse prognosis. We have evaluated the effectiveness of [225Ac]Ac-macropa-nimotuzumab in KRAS mutant and in KRAS wild-type and BRAFV600E mutant EGFR-positive CRC cells invitro and invivo. Anti-CD20 [225Ac]Ac-macropa-rituximab was developed and used as a nonspecific radioimmunoconjugate. Methods: Anti-EGFR antibody nimotuzumab was radiolabeled with 225Ac via an 18-membered macrocyclic chelator p-SCN-macropa. The immunoconjugate was characterized using flow cytometry, radioligand binding assay, and high-performance liquid chromatography, and internalization was studied using live-cell imaging. In vitro cytotoxicity was evaluated in 2-dimensional monolayer EGFR-positive KRAS mutant DLD-1, SW620, and SNU-C2B; in KRAS wild-type and BRAFV600E mutant HT-29 CRC cell lines; and in 3-dimensional spheroids. Dosimetry was studied in healthy mice. The invivo efficacy of [225Ac]Ac-macropa-nimotuzumab was evaluated in mice bearing DLD-1, SW620, and HT-29 xenografts after treatment with 3 doses of 13 kBq/dose administered 10 d apart. Results: In all cell lines, invitro studies showed enhanced cytotoxicity of [225Ac]Ac-macropa-nimotuzumab compared with nimotuzumab and controls. The inhibitory concentration of 50% in the DLD-1 cell line was 1.8 nM for [225Ac]Ac-macropa-nimotuzumab versus 84.1 nM for nimotuzumab. Similarly, the inhibitory concentration of 50% was up to 79-fold lower for [225Ac]Ac-macropa-nimotuzumab than for nimotuzumab in KRAS mutant SNU-C2B and SW620 and in KRAS wild-type and BRAFV600E mutant HT-29 CRC cell lines. A similar trend was observed for 3-dimensional spheroids. Internalization peaked 24-48 h after incubation and depended on EGFR expression. In the [225Ac]Ac-macropa-nimotuzumab group, 3 of 7 mice bearing DLD-1 tumors had complete remission. Median survival was 40 and 34 d for mice treated with phosphate-buffered saline and [225Ac]Ac-macropa-rituximab (control), respectively, whereas it was not reached for the [225Ac]Ac-macropa-nimotuzumab group (>90 d). Similarly, median survival of mice bearing HT-29 xenografts was 16 and 12.5 d for those treated with [225Ac]Ac-macropa-rituximab and phosphate-buffered saline, respectively, and was not reached for those treated with [225Ac]Ac-macropa-nimotuzumab (>90 d). One of 7 mice bearing HT-29 xenografts and treated using [225Ac]Ac-macropa-nimotuzumab had complete remission. Compared with untreated mice, [225Ac]Ac-macropa-nimotuzumab more than doubled (16 vs. 41 d) the median survival of mice bearing SW620 xenografts. Conclusion: [225Ac]Ac-macropa-nimotuzumab is effective against KRAS mutant and BRAFV600E mutant CRC models.

Epidemiology and Outcomes of Non–Small Cell Lung Cancer in South Korea

Valuable evidence regarding clinical characteristics, treatments, and outcomes for non-small cell lung cancer (NSCLC) is limited to individual hospital databases or national-level registries. The common data and federated analysis framework developed through the Extensible Platform for Observational Research in Lung Cancer (EXPLORE-LC) initiative allows for research across multiple high-quality data sources, which may provide a deeper understanding of the NSCLC landscape and identification of unmet needs of subpopulations. To describe clinical characteristics, initial treatment patterns, subsequent treatment, and overall survival (OS) of patients with NSCLC in South Korea. This multicenter cohort study included patients aged 18 years and older who were diagnosed with NSCLC between 2014 and 2019 and followed up until March 2020 at 3 tertiary hospitals in South Korea. Clinical data were collected using a common data model and clinical data warehouse. Patients who had an initial diagnosis of nonsquamous (NSQ) or squamous (SQ) NSCLC and who had received at least 1 treatment for NSCLC were included in the study. Data were analyzed from June through November 2022. The primary outcome was clinical OS for patients with NSCLC. Secondary outcomes were clinical characteristics and treatment patterns subsequent to the diagnosis of NSCLC. Among 22 101 patients with NSCLC who received anticancer treatment analyzed in this study, 17 350 patients (78.5%) had NSQ and 4751 patients (21.5%) had SQ NSCLC. Clinical characteristics and outcomes and treatment patterns were assessed for 13 084 patients with NSQ cancer who had known EGFR and ALK status (75.4%; mean [SD] 62.2 [10.5] years; 6552 males [50.1%]) and all 4751 patients with SQ cancer (mean [SD] age, 67.1 [8.6] years; 4427 males [93.2%]). More than half of patients with NSQ cancer were never smokers (7399 patients [56.6%]). Patients with SQ cancer were mostly males and former or current smokers (4235 patients [89.1%]) and were diagnosed at a later clinical stage than patients with NSQ cancer (eg, stage I: 1165 patients [24.5%] vs 5388 patients [41.2%]). Patients with EGFR-positive and ALK-positive NSQ cancer diagnosed between 2017 and 2019 had better median OS than similar patients diagnosed between 2014 and 2016 (EGFR-positive: not reached [95% CI, 35.9 months to not reached] vs 28.4 months [95% CI, 25.8 to 30.0 months]; P < .001; ALK-positive: not reached [95% CI, not reached] vs 49.5 months [95% CI, 35.1 months to not reached]; P < .001). No significant difference was observed in OS from first-line treatment for patients with SQ cancer. This study, which pooled medical data from multiple clinical data warehouses to produce a large study cohort, may provide meaningful insights into the clinical practice of NSCLC and underscores the value of a common data model approach. The analyzable dataset may hold great promise for future comprehensive identification of subpopulations and unmet needs.

Impact of body surface area on efficacy and safety in patients with EGFR-mutant non-small cell lung cancer treated with osimertinib as a first-line treatment

BackgroundThe most recommended treatment for stage IV EGFR-positive lung cancer is osimertinib monotherapy. The dosage of osimertinib is fixed at 80 mg/day regardless of body surface area (BSA), however some patients withdraw or reduce the dosage due to adverse events (AEs). MethodsWe performed a retrospective cohort study of 98 patients with EGFR mutation-positive non-small cell lung cancer (NSCLC), who received 80 mg osimertinib as the initial treatment. We investigated the impact of BSA on efficacy and safety of osimertinib. ResultsThe cut-off value of BSA was estimated using the receiver operating characteristics curve, and was determined to be 1.5 m2. There were 44 patients in the BSA < 1.5 group and 54 patients in the BSA ≥ 1.5 group. There was no significant difference in the incidence of AEs (hematologic toxicity of ≥grade 3 or higher, and non-hematologic toxicity of ≥grade 3) between the two groups. However, the incidence of dose reduction due to AEs was significantly higher in the BSA < 1.5 group compared with the BSA ≥ 1.5 group (16 patients vs 5 patients, p = 0.003). The main reasons were fatigue, anorexia, diarrhea, and liver disfunction. Median progression-free survival (PFS) was not significantly different (16.9 months in the BSA < 1.5 group vs 18.1 months in the BSA ≥ 1.5 group, p = 0.869). ConclusionDifferences in BSA affected the optimal dose of osimertinib. However, the PFS with osimertinib treatment was not affected by BSA. Therefore, when using osimertinib as an initial treatment for patients with EGFR-mutant NSCLC, dose reduction to control AEs should be considered, especially in the BSA<1.5 group.

EP12.01-42 Long-term Survivors with EGFR Positive Non-Small Cell Lung Cancer Treated with Tyrosine Kinase Inhibitors: A Combined Canadian Cohort

EP12.01-42 Long-term Survivors with EGFR Positive Non-Small Cell Lung Cancer Treated with Tyrosine Kinase Inhibitors: A Combined Canadian Cohort

Ganoderma microsporum immunomodulatory protein as an extracellular epidermal growth factor receptor (EGFR) degrader for suppressing EGFR-positive lung cancer cells

Epidermal growth factor receptor (EGFR) abnormalities relevant to tumor progression. A newly developed strategy for cancer therapy is induction of EGFR degradation. GMI, an immunomodulatory protein from the medicinal mushroom Ganoderma microsporum, exhibits anticancer activity. However, its role in the intracellular trafficking and degradation of EGFR remains unclear. In this study, we discovered that GMI inhibits the phosphorylation of multiple tyrosine kinases. Specifically, GMI was discovered to suppress lung cancer cells harboring both wild-type and mutant EGFR by inhibiting EGFR dimerization and eliminating EGFR-mediated signaling. Functional studies revealed that GMI binds to the extracellular segment of EGFR. GMI interacts with EGFR to induce phosphorylation of EGFR at tyrosine1045, which triggers clathrin-dependent endocytosis and degradation of EGFR. Furthermore, in the mouse models, GMI was discovered to suppress tumor growth. Knockdown of EGFR in lung cancer cells abolishes GMI's anticancer activity in vivo and in vitro. Our results reveal the interaction mechanisms through which GMI induces EGFR degradation and abolishes EGFR-mediated intracellular pathway. Our study indicates that GMI is an EGFR degrader for inhibiting EGFR-expressing tumor growth.

Ligand-installed polymeric nanocarriers for combination chemotherapy of EGFR-positive ovarian cancer

Combination chemotherapeutic drugs administered via a single nanocarrier for cancer treatment provides benefits in reducing dose-limiting toxicities, improving the pharmacokinetic properties of the cargo and achieving spatial-temporal synchronization of drug exposure for maximized synergistic therapeutic effects. In an attempt to develop such a multi-drug carrier, our work focuses on functional multimodal polypeptide-based polymeric nanogels (NGs). Diblock copolymers poly (ethylene glycol)-b-poly (glutamic acid) (PEG-b-PGlu) modified with phenylalanine (Phe) were successfully synthesized and characterized. Self-assembly behavior of the resulting polymers was utilized for the synthesis of NGs with hydrophobic domains in cross-linked polyion cores coated with inert PEG chains. The resulting NGs were small (ca. 70 nm in diameter) and were able to encapsulate the combination of drugs with different physicochemical properties such as cisplatin and neratinib. Drug combination-loaded NGs exerted a selective synergistic cytotoxicity towards EGFR overexpressing ovarian cancer cells. Moreover, we developed ligand-installed EGFR-targeted NGs and tested them as an EGFR-overexpressing tumor-specific delivery system. Both in vitro and in vivo, ligand-installed NGs displayed preferential associations with EGFR (+) tumor cells. Ligand-installed NGs carrying cisplatin and neratinib significantly improved the treatment response of ovarian cancer xenografts. We also confirmed the importance of simultaneous administration of the dual drug combination via a single NG system which provides more therapeutic benefit than individual drug-loaded NGs administered at equivalent doses. This work illustrates the potential of our carrier system to mediate efficient delivery of a drug combination to treat EGFR overexpressing cancers.

Dual receptor specific nanoparticles targeting EGFR and PD-L1 for enhanced delivery of docetaxel in cancer therapy

Dual-receptor targeted (DRT) nanoparticles which contain two distinct targeting agents may exhibit higher cell selectivity, cellular uptake, and cytotoxicity toward cancer cells than single-ligand targeted nanoparticle systems without additional functionality. The purpose of this study is to prepare DRT poly(lactic-co-glycolic acid) (PLGA) nanoparticles for targeting the delivery of docetaxel (DTX) to the EGFR and PD-L1 receptor positive cancer cells such as human glioblastoma multiform (U87-MG) and human non-small cell lung cancer (A549) cell lines. Anti-EGFR and anti-PD-L1 antibody were decorated on DTX loaded PLGA nanoparticles to prepare DRT-DTX-PLGA via. single emulsion solvent evaporation method. Physicochemical characterizations of DRT-DTX-PLGA, such as particle size, zeta-potential, morphology, and in vitro DTX release were also evaluated. The average particle size of DRT-DTX-PLGA was 124.2 ± 1.1 nm with spherical and smooth morphology. In the cellular uptake study, the DRT-DTX-PLGA endocytosed by the U87-MG and A549 cells was single ligand targeting nanoparticle. From the in vitro cell cytotoxicity, and apoptosis studies, we reported that DRT-DTX-PLGA exhibited high cytotoxicity and enhanced the apoptotic cell compared to the single ligand-targeted nanoparticle. The dual receptor mediated endocytosis of DRT-DTX-PLGA showed a high binding affinity effect that leads to high intracellular DTX concentration and exhibited high cytotoxic properties. Thus, DRT nanoparticles have the potential to improve cancer therapy by providing selectivity over single-ligand-targeted nanoparticles.

A Real-world Study on the Expression Characteristics of PD-L1 in Patients with Advanced EGFR Positive NSCLC and Its Relationship with the Therapeutic Efficacy of EGFR-TKIs

Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) is the first choice for first-line treatment of advanced patients with EGFR positive non-small cell lung cancer (NSCLC). For advanced NSCLC patients with negative drive gene and positive programmed cell death ligand 1 (PD-L1) or highly expressed NSCLC patients, the first-line treatment recommends immune checkpoint inhibitors (ICIs) monotherapy or ICIs combined chemotherapy. Therefore, the first-line treatment strategy for advanced NSCLC patients with EGFR positive at different PD-L1 expression levels is worth further exploring. Many previous studies have suggested that the expression of PD-L1 is obviously affected by EGFR mutation, and the expression of PD-L1 is likely to be related to the mechanism of EGFR-TKIs resistance. The purpose of this study was to analyze the expression characteristics of PD-L1 in patients with advanced EGFR positive NSCLC and its relationship with the efficacy of EGFR-TKIs. 159 patients with newly diagnosed advanced NSCLC with EGFR positive (including 141 patients with EGFR sensitive mutations) were enrolled to analyze the relationship between clinicopathological characteristics and PD-L1 expression. The factors affecting the therapeutic effect of EGFR-TKIs in 141 patients with EGFR sensitive mutations were also explored. The PD-L1 expression of the included patients was classified according to the tumor promotion score (TPS): negative (TPS<1%) accounted for 47.2%, low expression (1%≤TPS<50%) accounted for 32.1%, and high expression (TPS≥50%) accounted for 20.7%. Among them, patients with solid predominant cancer cell pathomorphology classification are more likely to have high expression of PD-L1, accounting for 52.9% (P<0.0001). The median progression-free survival (mPFS) of patients with PD-L1 negative expression, low expression and high expression who received first generation EGFR-TKIs treatment were 12.4 months, 10.5 months and 3.7 months, respectively, with significant statistical difference (P<0.0001). During the EGFR-TKIs treatment, patients with a history of radiotherapy for lung lesions have a longer PFS benefit than those without a history of radiotherapy (mPFS: 17.0 months vs 9.3 months, P<0.0001). The expression level of PD-L1 in advanced EGFR positive NSCLC patients was significantly correlated with the pathomorphology classification of cancer cells. The efficacy of EGFR-TKIs in patients with PD-L1 overexpression NSCLC was significantly poor. PFS can be significantly prolonged during targeted therapy combined with radiotherapy of lung lesions.

Catalyst-free thiazolidine formation chemistry enables the facile construction of peptide/protein-cell conjugates (PCCs) at physiological pH.

Although numerous genetic, chemical, and physical strategies have been developed to remodel the cell surface landscape for basic research and the development of live cell-based therapeutics, new chemical modification strategies capable of decorating cells with various genetically/non-genetically encodable molecules are still urgently needed. Herein, we describe a remarkably simple and robust chemical strategy for cell surface modifications by revisiting the classical thiazolidine formation chemistry. Cell surfaces harbouring aldehydes can be chemoselectively conjugated with molecules containing a 1,2-aminothiol moiety at physiological pH without the need to use any toxic catalysts and complicated chemical synthesis. Through the combined use of thiazolidine formation and the SpyCatcher-SpyTag system, we have further developed a SpyCatcher-SpyTag Chemistry Assisted Cell Surface Engineering (SpyCASE) platform, providing a modular approach for the construction of large protein-cell conjugates (PCCs) in their native state. Thiazolidine-bridged molecules can also be detached from the surface again through a biocompatible Pd-catalyzed bond scission reaction, enabling reversible modification of living cell surfaces. In addition, this approach allows us to modulate specific cell-cell interactions and generate NK cell-based PCCs to selectively target/kill several EGFR-positive cancer cells in vitro. Overall, this study provides an underappreciated but useful chemical tool to decorate cells with tailor-made functionalities.

Efficacy and safety of original EGFR-TKI combined with bevacizumab in advanced lung adenocarcinoma patients harboring EGFR-mutation experiencing gradual progression after EGFR-TKI treatment: a single-arm study.

Keeping on original epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) treatment is the standard treatment for gradual progression EGFR-positive metastatic non-small cell lung cancer (NSCLC). Angiogenic pathway can lead to EGFR-TKI resistance, but the effectiveness of combination strategies in this group is still controversial. This study aimed to assess the efficacy and safety of the original EGFR-TKI combined with bevacizumab in advanced and metastatic lung adenocarcinoma patients harboring EGFR-mutation who experience gradual progression in a real-world setting. From June 2019 to December 2021, a total of 35 metastatic EGFR positive NSCLC patients experienced gradual progression after EGFR-TKI treatments and received original TKI combined with bevacizumab were identified at Chongqing University Cancer Hospital, China. All patients were confirmed EGFR positive by rebiopsy before treatment. Patients were treated with EGFR-TKI and bevacizumab (15 mg/kg Q3W) after gradual progression until rapid progression or intolerable toxicity. The overall survival (OS), progression-free survival 1 (PFS1, period from the beginning of EGFR-TKI treatment to the rapid progression of the disease), PFS2 (period from the beginning of EGFR-TKI combined with bevacizumab treatment to the rapid progression of the disease), disease control rate (DCR), and adverse events of the combined treatment were collected and analyzed. A total of 33 patients could participate the efficacy evaluation. Median PFS1 and PFS2 were 20.5 and 8 months, respectively; DCR was 93.94%; median OS was immature. Multivariate Cox proportional hazards model showed that smoking status [hazard ratio (HR) =3.692, 95% confidence interval (CI): 1.450-9.404, P=0.006], combined EGFR T790M mutation or rare mutation (HR =2.480, 95% CI: 1.073-5.729, P=0.034), and malignant pleural effusion (HR =3.707, 95% CI: 1.460-9.414, P=0.006) were independent risk factors for PFS2. The most common treatment-related adverse events greater than grade 3 included hypertension (23.7%), proteinuria (8.3%), and increased alanine aminotransferase (ALT; 4.1%) and aspartate aminotransferase (AST; 2.9%). Continuous original TKI combined with bevacizumab showed partly favorable efficacy and safety and may represent a therapeutic option for metastatic EGFR-mutation NSCLC patients experiencing gradual progression after EGFR-TKI treatment.

Identification of a novel gene signature of lung adenocarcinoma based on epidermal growth factor receptor-tyrosine kinase inhibitor resistance.

Tyrosine kinase inhibitors (TKIs) that target epidermal growth factor receptor (EGFR) mutations are commonly administered to EGFR-positive lung cancer patients. However, resistance to EGFR-TKIs (mostly gefitinib and erlotinib) is presently a significant problem. Limited studies have focused on an EGFR-TKI resistance-related gene signature (ERS) in lung adenocarcinoma (LUAD). Gefitinib and erlotinib resistance-related genes were obtained through the differential analyses of three Gene Expression Omnibus datasets. These genes were investigated further in LUAD patients from The Cancer Genome Atlas (TCGA). Patients in the TCGA-LUAD cohort were split into two groups: one for training and one for testing. The training cohort was used to build the ERS, and the testing cohort was used to test it. GO and KEGG analyses were explored for the enriched pathways between the high-risk and low-risk groups. Various software, mainly CIBERSORT and ssGSEA, were used for immune infiltration profiles. Somatic mutation and drug sensitivity analyses were also explored. An ERS based on five genes (FGD3, PCDH7, DEPDC1B, SATB2, and S100P) was constructed and validated using the TCGA-LUAD cohort, resulting in the significant stratification of LUAD patients into high-risk and low-risk groups. Multivariable Cox analyses confirmed that ERS had an independent prognostic value in LUAD. The pathway enrichment analyses showed that most of the genes that were different between the two risk groups were related to the immune system. Further immune infiltration results revealed that a lower immune infiltration score was observed in high-risk patients, and that various leukocytes were significantly related to the ERS. Importantly, samples from the high-risk group showed lower levels of PD-1, PD-L1, and CTLA-4, which are important biomarkers for immunotherapy responses. Patients in the high-risk group also had more gene mutation changes and were more sensitive to chemotherapy drugs like docetaxel and sorafenib. The ERS was also validated in the GSE30219, GSE11969 and GSE72094, and showed a favorable prognostic value for LUAD patients. The ERS established during this study was able to predict a poor prognosis for LUAD patients and had great potential for predicting drug responses.