Epidermal Growth Factor Receptor Expression Research Articles

Effects of EGFR-TKI on epidermal melanin unit integrity: Therapeutic implications for hypopigmented skin disorders.

Epidermal melanin unit integrity is crucial for skin homeostasis and pigmentation. Epidermal growth factor (EGF) receptor (EGFR) is a pivotal player in cell growth, wound healing, and maintaining skin homeostasis. However, its influence on skin pigmentation is relatively unexplored. This study investigates the impact and underlying mechanisms of EGFR inhibitors on skin pigmentation. We evaluated EGF and EGFR expression in various skin cells using quantitative real-time PCR, Western blot, and immunofluorescence. EGF and EGFR were predominantly expressed in epidermal keratinocytes, and treatment with the EGFR tyrosine kinase inhibitors (EGFR-TKIs) gefitinib and PD153035 significantly increased stem cell factor (SCF) and endothelin-1 (ET-1) expression in cultured keratinocytes. Enhanced melanocyte migration and proliferation were observed in co-culture, as evidenced by time-lapse live imaging and single-cell tracking assays. Furthermore, topical application of gefitinib to guinea pig dorsal skin induced increased pigmentation and demonstrated efficacy in mitigating rhododendrol-induced leukoderma. Suppression of EGF signaling indirectly enhanced skin pigmentation by upregulating SCF and ET-1 in epidermal keratinocytes. This novel mechanism highlights the pivotal role of EGF signaling in regulating skin pigmentation, and topical EGFR-TKI therapy at an appropriate dose may be a promising approach for depigmentation disorder management.

Abstract PO1-25-03: Programmed Death-Ligand 1 and Receptor Tyrosine Kinases in Breast Cancer

Abstract Programmed death-ligand 1 (PD-L1) is an immune checkpoint expressed in a wide range of malignancies leading to immune tolerance and cancer cell immune evasion. Receptor tyrosine kinases (RTKs) are key regulators of cancer cell proliferation, survival, and invasion. The Hepatocyte Growth Factor (HGF) receptor, MET, and the Epidermal Growth Factor Receptor (EGFR) are RTKs known for their tumorigenic potential in a variety of human malignancies. This study aimed to evaluate the effect of the small-molecule tyrosine kinase inhibitors (TKIs) on the expression of PD-L1 in breast cancer cells and the effect of their combination with inflammatory cytokines. The study also assessed the association of the expression of the tumoral PD-L1 mRNA with each of MET and EGFR mRNA expression and the tumor features and treatment outcomes in breast cancer patients using the METABRIC dataset publicly available from cBioPortal for Cancer Genomics. The TKIs crizotinib [a MET inhibitor] and gefitinib [an EGFR inhibitor] were used as a single treatment and in combination with the cytokines; tumor necrosis factor-α (TNF-α) or interferon-γ (INF-γ) in MCF7 and MDA-MB-231 breast cancer cells in vitro. The cells were also treated with the mitogens HGF and EGF. The viability of cells after the different treatments was determined using the MTT viability assay. The effects of the combination treatments were analyzed using combination index (CI) analysis. The expression level of PD-L1 in cancer cells was assessed using Western blotting. The combination treatment of crizotinib with TNF-α and INF-γ produced a synergistic growth inhibition of MCF7 and MDA-MB-231 cells with CI values of 0.31 and 0.55, respectively. Alternatively, combined crizotinib and TNF-α produced an antagonist effect on the viability of MCF7 cells (CI=2.49). The combination of gefitinib with TNF-α produced a synergistic growth inhibition in both MCF7 and MDA-MB-231 cells with CI values of 0.39 and 0.78, respectively. Alternatively, gefitinib resulted in an additive effect when combined with INF-γ (CI=0.99) and an antagonistic effect when combined with TNF-α (CI=2.68) in MCF7 and MDA-MB-231 cells, respectively. Treatment with HGF (50 and 100 ng/ml) increased the protein levels of PD-L1 while EGF (50 and 100 ng/ml) reduced its levels in MDA-MB-231 cells. Treatment with the TKIs crizotinib (0.1-4 µM) and gefitinib (1-40 µM) significantly reduced PD-L1 levels in MDA-MB-231 cells compared to vehicle-treated cells. The analysis of the METABRIC dataset revealed that the mRNA expression of PD-L1 was positively correlated with the mRNA expression of the EGFR gene (r= 0.081, p< 0.001) but not the MET gene. A double-high PD-L1/MET expression was significantly associated with younger age at diagnosis, high-grade carcinoma, greater tumor size, hormone receptor-negative status, HER2-positivity, and non-luminal disease compared to patients with a double-low PD-L1/MET expression. Similar findings were reported for patients with a double-high PD-L1/EGFR expression compared to patients with a double-low PD-L1/EGFR expression. Nevertheless, the mRNA expression of the PD-L1, MET, and EGFR genes as well as the co-expression of PD-L1/MET or PD-L1/EGFR genes did not affect the overall survival of breast cancer patients. Collectively, MET and EGFR TKIs could modulate the effects of inflammatory cytokines differently based on the type of cytokine and the molecular subtype of breast cancer cells. The expression of PD-L1 in breast cancer cells was upregulated by HGF while TKIs reduced its expression. The co-expression of the PD-L1 gene with MET and EGFR genes in breast cancer was associated with advanced disease presentation and worse prognosticators in patients. Together, TKIs that target MET or EGFR could be an appealing therapeutic target in breast cancer, particularly in younger patients with the non-luminal disease. Citation Format: Nehad Ayoub, Muhsen Al-Diabat, Moath Al-Shorman, Laith Al-Eitan. Programmed Death-Ligand 1 and Receptor Tyrosine Kinases in 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 PO1-25-03.

Predictive value of PD-L1 and TMB for short-term efficacy prognosis in non-small cell lung cancer and construction of prediction models

ObjectiveTo investigate the correlation between programmed death ligand 1(PD-L1), tumor mutation burden (TMB) and the short-term efficacy and clinical characteristics of anti-PD-1 immune checkpoint inhibitor combination chemotherapy in NSCLC patients. The efficacy of the prediction model was evaluated.MethodsA total of 220 NSCLC patients receiving first-line treatment with anti-PD-1 immune checkpoint inhibitor combined with chemotherapy were retrospectively collected. The primary endpoint was short-term efficacy ORR. The correlation between short-term efficacy, PD-L1, TMB, and clinical characteristics using χ2 test or t-test was evaluated. Screen the independent prognostic factors using univariate and multivariate logistic regression analyses, and construct a nomogram prediction model using the “rms” package in R software. Using receiver operating characteristic (ROC) curve analysis to evaluate the independent Prognostic factors and the prediction model. Using decision curve analysis (DCA) to verify the superiority of the prediction model.ResultsThe mean values of PD-L1, TMB, neutrophils, lymphocytes, neutrophil-to-lymphocyte ratio, and albumin were the highest in the ORR group, PD-L1 expression and TMB correlated with epidermal growth factor receptor expression. Multivariate analyses showed that PD-L1, TMB, and neutrophil were independent prognostic factors for ORR. The area under the ROC curve (AUC) values of the ROC constructed based on these three indicators were 0.7104, 0.7139, and 0.7131, respectively. The AUC value under the ROC of the nomogram model was 0.813. The DCA of the model showed that all three indicators used together to build the prediction model of the net return were higher than those of the single indicator prediction model.ConclusionPD-L1, TMB, and neutrophils are independent prognostic factors for short-term efficacy. The nomogram prediction model constructed using these three indicators can further improve predictive efficacy of ICIs in patients with NSCLC.

Abstract PO2-05-12: Retrospective analysis on therapeutic efficacy and predictive indicators of eribulin plus anti-angiogenic drugs for metastatic breast cancer

Abstract Background: Eribulin has been widely used for the treatment of metastatic breast cancer (MBC). It has been found that eribulin can work in synergy with Bevacizumab or Anlotinib to achieve anti-angiogenic effects and possible synergistic enhancement. To optimize the efficacy of eribulin usage in late-line MBC patients, it is essential to delve deeper into the effects of combined treatments and gather more real-world clinical outcomes. Therefore, we evaluated the efficacy and safety of eribulin plus the anti-angiogenic drugs in late-line MBC patients. Objective: This study aims to retrospectively analyze the therapeutic efficacy and safety of eribulin plus anti-angiogenic drugs in treating metastatic breast cancer and explore predictive indicators of the therapeutic efficacy of eribulin in treating MBC. Methods: A retrospective review study was performed. 40 Patients diagnosed with MBC and treated with eribulin in Xi’an international medical center hospital from May 2020 to May 2021 were enrolled in this study. Patients were evaluable for this study and divided into two groups based on whether they received eribulin monotherapy or combined therapy. 22 patients were treated with eribulin monotherapy, and 18 were treated with eribulin and anti-angiogenic drugs (Bevacizumab and Anlotinib). Patients’ treatment parameters and characteristics were recorded. The Kaplan-Meier method was used to calculate the median PFS and corresponding 95% confidence interval (CI), and the Cox regression model was used for multivariate analysis of predictive indicators. The Fisher exact probability test was used to compare the difference in adverse reactions between the two groups, with a level of significance set at p-value < 0.05. Results: All study patients have an average of 5 treatment lines and a median progression-free survival (mPFS) of 4.2 months. The eribulin plus anti-angiogenic drug treatment group had a significantly prolonged mPFS compared to the group without anti-angiogenic drug treatment (7.0 months vs 2.0 months, p < 0.001, log-rank). Multivariate analysis identified that the combination of anti-angiogenic therapy (HR = 0.043, p = 0.004) and the occurrence of grade 3-4 neutropenia after treatment were two predictive factors for longer PFS (HR = 0.322, p = 0.009). In contrast, prior resistance to taxanes was predictive of shorter PFS (HR = 4.583, p = 0.019). Other factors, including age, Eastern Cooperative Oncology Group (ECOG) performance status, hormone receptor (HR) type, expression status, human epidermal growth factor receptor-2 (HER-2) expression status, Ki-67 level, number of metastatic lesions, and number of prior lines of Eribulin therapy, were not significantly associated with PFS. The results of Fisher’s exact test show that there was no significant increase in treatment-related adverse events (all grades) after combination with anti-angiogenic drugs. Conclusion: A combination of eribulin and anti-angiogenic therapy has significantly prolonged mPFS in the treatment of MBC patients. Other factors such as prior non-taxane resistance, grade 3-4 neutropenia occurrence after treatment, and combined anti-angiogenic therapy can be used as biomarkers for predicting treatment efficacy. The adverse events are manageable and the safety of combined therapy can be guaranteed. Therefore, the eribulin plus anti-angiogenic combination may act as a potential therapy for late-line MBC patients with clinically beneficial therapeutic effects. Keywords: metastatic breast cancer, eribulin, anti-angiogenic therapy, retrospective analysis Citation Format: Junmei Zhang, Xuezheng Wang, Hongjuan Du, Yan Xue. Retrospective analysis on therapeutic efficacy and predictive indicators of eribulin plus anti-angiogenic drugs for metastatic 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 PO2-05-12.

EGFR-mediated crosstalk between vascular endothelial cells and hepatocytes promotes Piezo1-dependent liver regeneration

Hepatocyte proliferation is essential for recovering liver function after injury. In liver surgery, the mechanical stimulation induced by hemodynamic changes triggers vascular endothelial cells (VECs) to secrete large amounts of cytokines that enhance hepatocyte proliferation and play a pivotal role in liver regeneration. Piezo1, a critical mechanosensory ion channel, can detect and convert mechanical forces into chemical signals, importing external stimuli into cells and triggering downstream biological effects. However, the precise role of Piezo1 in VECs, especially in terms of mediating liver regeneration, remains unclear. Here, we report on a potential mechanism by which early changes in hepatic portal hemodynamics activate Piezo1 in VECs to promote hepatocyte proliferation during the process of liver regeneration induced by portal vein ligation in rats. In this liver regeneration model, hepatocyte proliferation is mainly distributed in zone 1 and zone 2 of liver lobules at 24–48 h after surgery, while only a small number of Ki67-positive hepatocytes were observed in zone 3. Activation of Piezo1 promotes increased secretion of epiregulin and amphiregulin from VECs via the PKC/ERK1/2 axis, further activating epidermal growth factor receptor (EGFR) and ERK1/2 signals in hepatocytes and promoting proliferation. In addition, cytokines secreted by Piezo1-activated VECs can induce hepatocytes to undergo epithelial–mesenchymal transition. In the liver lobules, the expression of EGFR in hepatocytes of zone 1 and zone 2 is significantly higher than that in zone 3. The EGFR inhibitor gefitinib inhibits liver regeneration by suppressing the proliferation of hepatocytes in the middle zone. Thus, activation of Piezo1 in VECs promotes hepatocyte proliferation, suggesting mechanical stimulation regulates hepatocyte proliferation in zone 1 and zone 2 during portal vein ligation-induced liver regeneration. These data provide a theoretical basis for the regulation of liver regeneration through chemical signals mediated by mechanical stimulation.

The involvement of epidermal growth factor receptor/protein kinase Bsignaling in the tumor intrinsic PD-L1-induced malignant potential of oral squamous cell carcinoma.

Various antigen-presenting cells and tumor cells-expressing PD-L1 inhibits antitumor immune responses in the tumor microenvironment. Recently, numerous studies have shown that tumor cell intrinsic PD-L1 also plays important roles in tumor growth and progression. On the other hand, oral squamous cell carcinoma (OSCC) cells overexpress epidermal growth factor receptor (EGFR) and EGFR signal pathway exacerbates tumor progression. Therefore, this study assessed whether tumor-intrinsic PD-L1 facilitates malignant potential of OSCC cells through regulation of EGFR signaling. Two OSCC cell lines, SAS and HSC-3, were transfected with PD-L1 and EGFR-specific small interfering RNA (siRNA). Influences of PD-L1 knockdown on malignant potentials of OSCC cells were examined by Cell Counting kit-8 assay, transwell assay, sphere formation assay, flow cytometry, and Western blot. Effects of PD-L1 and EGFR knockdown on each expression were examined by quantitative real-time PCR (qRT-PCR), Western blot, and flow cytometry. Transfection of an PD-L1-siRNA into OSCC cells decreased the abilities of proliferation, stemness, and mobility of these cells significantly. PD-L1 knockdown also decreased EGFR expression through the promotion of proteasome- and lysosome-mediated degradation and following activation of the EGFR/protekin kinase B (AKT)signal pathway. Meanwhile, EGFR knockdown did not influence PD-L1 expression in SAS and HSC-3 cells, but treatment with a recombinant human EGF induced its expression. Treatment with erlotinib and cetuximab suppressed rhEGF-induced PD-L1 expression and localization in the cellular membrane of both OSCC cells. OSCC cells-expressing PD-L1 induced by EGF stimulation may promote malignancy intrinsically via the activation of the EGFR/AKT signaling cascade.

Varlitinib and Paclitaxel for EGFR/HER2 Co-Expressing Advanced Gastric Cancer: a Multicenter Phase Ib/II Study (K-MASTER-13).

Varlitinib is a pan-human epidermal growth (HER) inhibitor targeting epidermal growth factor receptor (EGFR), HER2, and HER4. We present a phase Ib/II study of a combination of varlitinib and weekly paclitaxel as a second-line treatment for patients with EGFR/HER2 co-expressing advanced gastric cancer (AGC). Patients whose tumors with EGFR and HER2 overexpression by immunohistochemistry (IHC) (≥1+) were enrolled. Varlitinib and paclitaxel were investigated every 4 weeks. After determining the recommended phase II dose (RP2D) in phase Ib, a phase II study was conducted to evaluate the antitumor activity. RP2D was treated with a combination of varlitinib (300 mg twice daily) and paclitaxel. Among 27 patients treated with RP2D, the median PFS and overall survival (OS) were 3.3 months and 7.9 months, respectively, with a median follow-up of 15.7 months. Among 16 patients with measurable disease, the objective response rate (ORR) and disease control rate were 31% and 88%, respectively. Patients with strong HER2 expression (n=8) had a higher ORR and longer OS, whereas those with strong EGFR expression (n=3) had poorer outcomes. The most common adverse events (AEs) of any grade were neutropenia (52%), diarrhea (27%), AST/ALT elevation (22%), and nausea (19%). No treatment-related deaths or unexpected AEs resulting from treatment cessation were observed in patients with RP2D. A combination of varlitinib and paclitaxel displayed manageable toxicity and modest antitumor activity in patients with EGFR/HER2 co-expressing AGC who progressed after first-line chemotherapy.

Cetuximab–Toxin Conjugate and NPe6 with Light Enhanced Cytotoxic Effects in Head and Neck Squamous Cell Carcinoma In Vitro

Background: Photodynamic therapy (PDT) is a cancer-targeted treatment that uses a photosensitizer (PS) and irradiation of a specific wavelength to exert cytotoxic effects. To enhance the antitumor effect against head and neck squamous cell carcinoma (HNSCC), we developed a new phototherapy, intelligent targeted antibody phototherapy (iTAP). This treatment uses a combination of immunotoxin (IT) and a PS for PDT and light irradiation. In our prior study, we demonstrated that an immunotoxin (IT) consisting of an anti-ROBO1 antibody conjugated to saporin, when used in combination with the photosensitizer (PS) disulfonated aluminum phthalocyanine (AlPcS2a) and irradiated with light at the appropriate wavelength, resulted in increased cytotoxicity against head and neck squamous cell carcinoma (HNSCC) cells. ROBO1 is a receptor known to be involved in the progression of cancer. In this study, we newly investigate the iTAP targeting epidermal growth factor receptor (EGFR) which is widely used as a therapeutic target for HNSCC. Methods: We checked the expression of EGFR in HNSCC cell lines, SAS, HO-1-u-1, Sa3, and HSQ-89. We analyzed the cytotoxicity of saporin-conjugated anti-EGFR antibody (cetuximab) (IT-Cmab), mono-L-aspartyl chlorin e6 (NPe6, talaporfin sodium), and light (664 nm) irradiation (i.e., iTAP) in SAS, HO-1-u-1, Sa3, and HSQ-89 cells. Results: EGFR was expressed highly in Sa3, moderately in HO-1-u-1, SAS, and nearly not in HSQ-89. Cmab alone or IT-Cmab alone did not show cytotoxic effects in Sa3, HO-1-u-1, and HSQ-89 cells, which have moderate or low expression levels of EGFR protein. However, the iTAP method enhanced the cytotoxicity of IT-Cmab by the photodynamic effect in Sa3 and HO-1-u-1 cells, which have moderate levels of EGFR expression. Conclusion: Our study is the first to report on the iTAP method using IT-Cmab and NPe6 for HNSCC. The cytotoxic effects are enhanced in cell lines with moderate levels of EGFR protein expression, but not in nonexpressing cell lines, which is expected to expand the range of therapeutic windows and potentially reduce complications.

Oocyte Competence of Prepubertal Sheep and Goat Oocytes: An Assessment of Large-Scale Chromatin Configuration and Epidermal Growth Factor Receptor Expression in Oocytes and Cumulus Cells.

The oocyte competence of prepubertal females is lower compared to that of adults, mainly because they originate from small follicles. In adult females, the germinal vesicle (GV) and epidermal growth factor receptor (EGFR) have been associated with oocyte competence. This study aimed to analyze GV chromatin configuration and EGFR expression in prepubertal goat and sheep oocytes obtained from small (<3 mm) and large (≥3 mm) follicles and compare them with those from adults. GV chromatin was classified from diffuse to condensed as GV1, GVn, and GVc for goats and NSN, SN, and SNE for sheep. EGFR was quantified in cumulus cells (CCs) by Western blotting and in oocytes by immunofluorescence. Oocytes from prepubertal large follicles and adults exhibited highly condensed chromatin in goats (71% and 69% in GVc, respectively) and sheep (59% and 75% in SNE, respectively). In both species, EGFR expression in CCs and oocytes was higher in prepubertal large follicles than in small ones. In adult females, EGFR expression in oocytes was higher than in prepubertal large follicles. In conclusion, GV configuration and EGFR expression in CCs and oocytes were higher in the large than small follicles of prepubertal females.

Role of Epiregulin on Lipopolysaccharide-Induced Hepatocarcinogenesis as a Mediator via EGFR Signaling in the Cancer Microenvironment.

Lipopolysaccharides (LPSs) have been reported to be important factors in promoting the progression of hepatocellular carcinoma (HCC), but the corresponding molecular mechanisms remain to be elucidated. We hypothesize that epiregulin (EREG), an epidermal growth factor (EGF) family member derived from hepatic stellate cells (HSCs) and activated by LPS stimulation, is a crucial mediator of HCC progression with epidermal growth factor receptor (EGFR) expression in the tumor microenvironment. We used a mouse xenograft model of Huh7 cells mixed with half the number of LX-2 cells, with/without intraperitoneal LPS injection, to elucidate the role of EREG in LPS-induced HCC. In the mouse model, LPS administration significantly enlarged the size of xenografted tumors and elevated the expression of EREG in tumor tissues compared with those in negative controls. Moreover, CD34 immunostaining and the gene expressions of angiogenic markers by a reverse transcription polymerase chain reaction revealed higher vascularization, with increased interleukin-8 (IL-8) expression in the tumors of the mice group treated with LPS compared to those without LPS. Our data collectively suggested that EREG plays an important role in the cancer microenvironment under the influence of LPS to increase not only the tumor cell growth and migration/invasion of EGFR-positive HCC cells but also tumor neovascularization via IL-8 signaling.

PDZK1 suppresses TNBC development and sensitizes TNBC cells to erlotinib via the EGFR pathway

Epidermal growth factor receptor (EGFR)-targeted drugs (erlotinib, etc.) are used to treat multiple types of tumours. EGFR is highly expressed in most triple-negative breast cancer (TNBC) patients. However, only a small proportion of TNBC patients benefit from EGFR-targeted drugs in clinical trials, and the resistance mechanism is unclear. Here, we found that PDZ domain containing 1 (PDZK1) is downregulated in erlotinib-resistant TNBC cells, suggesting that PDZK1 downregulation is related to erlotinib resistance in TNBC. PDZK1 binds to EGFR. Through this interaction, PDZK1 promotes EGFR degradation by enhancing the binding of EGFR to c-Cbl and inhibits EGFR phosphorylation by hindering EGFR dimerisation. We also found that PDZK1 is specifically downregulated in TNBC tissues and correlated with a poor prognosis in TNBC patients. In vitro and in vivo functional assays showed that PDZK1 suppressed TNBC development. Restoration of EGFR expression or kinase inhibitor treatment reversed the degree of cell malignancy induced by PDZK1 overexpression or knockdown, respectively. PDZK1 overexpression sensitised TNBC cells to erlotinib both in vitro and in vivo. In conclusion, PDZK1 is a significant prognostic factor for TNBC and a potential molecular therapeutic target for reversing erlotinib resistance in TNBC cells.

Abstract LB056: IBI334, a novel ADCC-enhanced B7-H3/EGFR bispecific antibody, demonstrated potent pre-clinical efficacy in solid tumors

Abstract Many solid tumors, such as colorectal cancer (CRC) and lung cancer, are dependent on epidermal growth factor receptor (EGFR) pathway for tumor growth. Antibodies that inhibit EGFR signaling, such as Cetuximab, show clinical efficacy but are associated with on-target toxicities that potentially limit the drug efficacy. To enhance the EGFR signaling inhibition and reduce on-target toxicities, we performed bioinformatics analysis for EGFR/TAA co-expression. We found that B7-H3, a member of the B7 family of immune checkpoint proteins, is broadly expressed in many solid tumors and their expression correlates with EGFR expression in multiple cancers, including lung cancer, head and neck cancer, pancreatic cancer and esophageal cancer. Using Innovent’s proprietary Innobody platform, we developed a bispecific antibody, IBI334, against B7-H3 and EGFR. IBI334 has an EGFR arm for signal blockage and is coupled with a fine-tuned B7-H3 arm with optimal affinity and binding domain. With the aid of B7-H3, IBI334 showed enhanced EGFR signal inhibition than Zalutumumab (EGFR mAb) and Amivantamab (c-met/EGFR bsAb). In addition, IBI334 is afucosylated to enhance its antibody-mediated cell cytotoxicity (ADCC) effects as compared to wild type antibody. IBI334 showed significantly better in vivo efficacy than Amivantamab in NCI-H358 (bronchioalveolar carcinoma with KRAS-G12C mutation), NCI-H292 (lymph node metastasis of a pulmonary mucoepidermoid carcinoma), SK-MES1 (lung cancer) and SK-MES1-LTC (lung cancer with EGFR L858R, T790M and C797S mutations) xenograft models and comparable efficacy in NCI-H322-EGFRexon20ins (lung cancer) model. Cetuximab, an EGFR monoclonal antibody, had high on-target toxicity with 50% early mortalities in cynomolgus monkeys at 120/75 mg/kg/week. With the careful design of B7-H3/EGFR bispecific antibody, IBI334 ameliorated the on-target toxicities and showed only slight hardening of the skin at the injection site at 120 mg/kg/week. As a result, IBI334 has a large therapeutic window of &amp;gt;200 folds. In conclusion, IBI334 is a potent B7-H3/EGFR bispecific antibody with broad application in many EGFR-driven solid tumors. The large therapeutic window enables safe and effective cancer treatment at high exposure levels. Citation Format: Jian Guan, Shuaixiang Zhou, Weiwei Wu, Tianyu Zhu, Lei Cao, Ming Wu, Ninghuan Li, Fenggen Fu, Zhengguan Liao, Shuming Lin, Zeyu Liu, Mengjia Zhu, Nana Luo, Ying Zhang, Tiong Sun Chia, Bingliang Chen, Kaijie He. IBI334, a novel ADCC-enhanced B7-H3/EGFR bispecific antibody, demonstrated potent pre-clinical efficacy in solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB056.

Abstract CT126: A Phase 0 Study of EGF-Depleting Therapy CIMAvax-EGF in Combination With Standard Therapy for RAS- and BRAF Wild-Type Metastatic Colorectal Cancer

Abstract Background: Colorectal Cancer (CRC) is the 3rd most common cancer in the US and a leading cause of cancer-related death. The epidermal growth factor receptor (EGFR) is overexpressed by immunohistochemistry (IHC) in up to 60% of CRC and is a relevant target for treatment. Monoclonal antibodies targeting the EGFR (cetuximab, panitumumab) have been in clinical use since 2004 as single agents as well as in combination with chemotherapeutics for patients with metastatic CRC, however primary and secondary resistance is very common. CIMAvax-EGF® (CIMAvax) vaccinates against one of the main EGFR ligands: the epidermal growth factor (EGF) protein. The vaccine is based on active immunotherapy where an individual’s immune response is manipulated to release its own effector antibodies against circulating EGF. We hypothesize that adding CIMAvax-EGF to standard chemotherapy has the potential to elicit an immune response against EGF for RAS- and BRAF wild-type metastatic CRC. Methods: This is a phase 0 study to evaluate CIMAvax in combination with standard therapy for RAS- and BRAF wild-type metastatic CRC. Patients will be treated with chemotherapy/biologic agent plus CIMAvax 2.4 mg (DL 1); DL -1 is 1.2 mg. The starting dose is the dose currently established as recommended dose in combination with immunotherapy in patients with non-small cell lung cancer. Cohorts A, B1 and B2 will enroll each 6-12 patients. Based on the known CIMAvax safety profile, we expect to enroll 18-20 patients in these cohorts. Cohort C will enroll 4-6 patients. Cohort A will enroll patients who have not received prior therapy for advanced disease. Patients in Cohort A will be treated with mFOLFOX6/Bevacizumab/CIMAvax at present. Cohort B will enroll patients who have received at least one but no more than 2 prior therapies for advanced disease. Cohort B is comprised of 2 sub-Cohorts. The standard therapy backbone in Cohort B1 will be FOLFIRI/anti-EGFR therapy, and in Cohort B2 mFOLFOX6/anti-EGFR therapy. Cohort C will enroll patients who have not received prior therapy for advanced disease and are candidates for liver metastasectomy. Cohort C will start accruing after the safety run-in phase in Cohorts A, and B2 are completed. The primary objective of this study is to determine the immunogenicity of CIMAvax in the 1st and 2nd/3rd line setting. Secondary objectives include determining the safety and efficacy of these combinations in this patient population and PFS. Exploratory objectives include evaluation of immunomodulation in the tumor microenvironment in patients undergoing metastasectomy of liver metastases, predictive/prognostic role of EGFR ligands (such as EGF, epiregulin, and amphiregulin), somatic mutation profile, EGFR expression by IHC and EGFR copy number alterations/mRNA expression. This trial is currently open for accrual. Clinicaltrials.gov number NCT06011772 Citation Format: Deepak Vadehra, Cayla Janes, Rachel Frascati, Mary Reid, Tania C. Ramos, Sarbajit Mukherjee, Kalet L. Monzón, Patricia L. Alvárez, Orestes S. Morales, Circe M. Pardillo, Christos Fountzilas. A Phase 0 Study of EGF-Depleting Therapy CIMAvax-EGF in Combination With Standard Therapy for RAS- and BRAF Wild-Type Metastatic Colorectal Cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT126.

Human epidermal growth factor receptor-2 expression and subsequent dynamic changes in patients with ovarian cancer

Human epidermal growth factor receptor-2 (HER2)-targeting drugs are increasingly being incorporated into therapeutic paradigms for non-breast cancers, yet studies on HER2 expression in ovarian cancer (OC) are inadequate. Here, we studied the HER2 status and dynamic changes in OC by reviewing the records of patients who underwent HER2 testing at a single institution. Clinical parameters, including histology, BRCA status, and immunohistochemistry (IHC), were evaluated alongside HER2 expression, timing, and anatomical location. Among 200 patients, 28% and 6% exhibited expression scores of 2+ and 3+, respectively. HER2 3+ scores were observed in 23%, 11%, 9%, and 5% of mucinous, endometrioid, clear cell, and high-grade serous tumors, respectively, and were exclusively identified in BRCA-wildtype, mismatch repair-proficient, or PD-L1-low-expressing tumors. The TP53 mutation rate was low, whereas ARID1A, KRAS, and PIK3CA mutations were relatively more prevalent with HER2 scores of 2+ or 3+ than with 0 or 1+. Four of the five tumors with an HER2 3+ score exhibited ERBB2 amplification. Among 19 patients who underwent multiple time-lagged biopsies, 11 showed increased HER2 expression in subsequent biopsies. Patients with HER2-overexpressing OC exhibited distinct histological, IHC, and genomic profiles. HER2-targeting agents are potential options for BRCA-wildtype patients, particularly as later lines of treatment.

Abstract CT078: Phase 1 study of SGN-EGFRd2 in solid tumors (SGNEGFRd2-001)

Abstract Background: Epidermal growth factor receptor (EGFR) is a cell surface receptor expressed in a variety of solid tumors. Gamma delta (γδ)-T cells represent a conserved T cell subset that can induce cell death in a wide range of malignancies. The presence of γ9δ2-T cells in solid tumors strongly correlates with better patient survival (Gentles 2015; Tosolini 2017). In addition to direct, potent killing by release of cytotoxic molecules, activated γ9δ2-T cells process and present antigen and contribute to a cascade response resulting in downstream activation of innate and adaptive immune cells to mediate further tumor cell killing (Brandes 2005; Devilder 2006; Vantourout 2013). Novel approaches that improve targeting and activation of γ9δ2-T cells may lead to the development of effective and safe cancer treatments. SGN-EGFRd2 is an investigational, bispecific humanized heavy chain-only antibody (HcAb). Advantages of HcAbs include their small size, high solubility, high stability, and excellent tissue penetration in vivo (Bannas 2017). SGN-EGFRd2 simultaneously binds EGFR and the γ9δ2-T cell receptor, resulting in the conditional activation of γ9δ2-T cells. Importantly, full activation of γ9δ2-T cells requires a secondary phosphoantigen stress signal present only in malignant and certain infected cells (Deseke 2020; Herrmann 2020; Rigau 2020; Vantourout 2013), but not normal healthy cells, conferring preferential tumor-directed cytotoxicity. The proposed cytotoxic mechanism of action is independent of KRAS and BRAF mutations (King 2023) known to confer resistance to approved anti-EGFR therapies in colorectal cancer (CRC). This first-in-human study is evaluating the safety, tolerability, and antitumor activity of SGN-EGFRd2 in patients with advanced solid tumors. Methods: SGNEGFRd2-001 (NCT05983133) is an open-label, multicenter, phase 1, dose escalation and expansion study evaluating SGN-EGFRd2 monotherapy in patients with relapsed/refractory (R/R) CRC, head and neck squamous cell cancer, non-small cell lung cancer, and pancreatic ductal adenocarcinoma in 3 parts: dose escalation (Part A; n ~ 75), dose optimization (Part B; optional; up to n = 40), and dose expansion (Part C; up to n = 160). Patients must have R/R disease, or be intolerant to standard of care therapies, with no appropriate standard therapy available. Patients must have measurable disease per RECIST v1.1, an ECOG performance status of 0 or 1, and adequate organ function. Patients are eligible regardless of tumor EGFR expression or EGFR/KRAS/BRAF mutation status. Patients will receive SGN-EGFRd2 as an intravenous infusion. Primary study objectives are safety and tolerability, maximum tolerated dose, and recommended dose and schedule. Secondary objectives include pharmacokinetics, immunogenicity, and antitumor activity. Tumor samples will be analyzed for exploratory biomarkers. Accrual is ongoing in the US. Additional sites in Europe and Canada are planned. Citation Format: Hirva Mamdani, Joel Randolph Hecht, Rachel E. Sanborn, Maria Corinna Palanca-Wessels, Mingjin Yan, Martin Gutierrez, David L. Bajor. Phase 1 study of SGN-EGFRd2 in solid tumors (SGNEGFRd2-001) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT078.

Near-infrared imaging of head and neck squamous cell carcinoma using indocyanine green that targets the peptide.

Head and neck squamous cell carcinoma (HNSCC) has a particularly poor prognosis. Improving the surgical resection boundary, reducing local recurrence, and ultimately ameliorating the overall survival rate are the treatment goals. To obtain a complete surgical resection (R0 resection), we investigated the use of a fluorescent imaging probe that targets the integrin subtype , which is upregulated in many kinds of epithelial cancer, using animal models. expression was detected using polymerase chain reaction (PCR) and immunoprotein blotting of human tissues for malignancy. Protein expression localization was observed. and epidermal growth factor receptor (EGFR) were quantified by PCR and immunoprotein blotting, and the biosafety of targeting the probe material was examined using Cell Counting Kit-8 assays. Indocyanine green (ICG) was used as a control to determine the localization of the probe at the cellular level. In vivo animal experiments were conducted through tail vein injections to evaluate the probe's imaging effect and to confirm its targeting in tissue sections. expression was higher than EGFR expression in HNSCC, and the probe showed good targeting in in vivo and in vitro experiments with a good safety profile. The ICG- peptide probe is an exceptional and sensitive imaging tool for HNSCC that can distinguish among tumor, normal, and inflammatory tissues.

A Novel Network Pharmacology Strategy Based on the Universal Effectiveness-Common Mechanism of Medical Herbs Uncovers Therapeutic Targets in Traumatic Brain Injury.

Many herbs can promote neurological recovery following traumatic brain injury (TBI). There must lie a shared mechanism behind the common effectiveness. We aimed to explore the key therapeutic targets for TBI based on the common effectiveness of the medicinal plants. The TBI-effective herbs were retrieved from the literature as imputes of network pharmacology. Then, the active ingredients in at least two herbs were screened out as common components. The hub targets of all active compounds were identified through Cytohubba. Next, AutoDock vina was used to rank the common compound-hub target interactions by molecular docking. A highly scored compound-target pair was selected for in vivo validation. We enrolled sixteen TBI-effective medicinal herbs and screened out twenty-one common compounds, such as luteolin. Ten hub targets were recognized according to the topology of the protein-protein interaction network of targets, including epidermal growth factor receptor (EGFR). Molecular docking analysis suggested that luteolin could bind strongly to the active pocket of EGFR. Administration of luteolin or the selective EGFR inhibitor AZD3759 to TBI mice promoted the recovery of body weight and neurological function, reduced astrocyte activation and EGFR expression, decreased chondroitin sulfate proteoglycans deposition, and upregulated GAP43 levels in the cortex. The effects were similar to those when treated with the selective EGFR inhibitor. The common effectiveness-based, common target screening strategy suggests that inhibition of EGFR can be an effective therapy for TBI. This strategy can be applied to discover core targets and therapeutic compounds in other diseases.

Targeting the EGFR pathway: An alternative strategy for the treatment of tuberous sclerosis complex?

Tuberous sclerosis complex (TSC) is caused by variants in TSC1/TSC2, leading to constitutive activation of the mammalian target of rapamycin (mTOR) complex 1. Therapy with everolimus has been approved for TSC, but variations in success are frequent. Recently, caudal late interneuron progenitor (CLIP) cells were identified as a common origin of the TSC brain pathologies such as subependymal giant cell astrocytomas (SEGA) and cortical tubers (CT). Further, targeting the epidermal growth factor receptor (EGFR) with afatinib, which is expressed in CLIP cells, reduces cell growth in cerebral TSC organoids. However, investigation of clinical patient-derived data is lacking. Observation of EGFR expression in SEGA, CT and focal cortical dysplasia (FCD) 2B human brain specimen and investigation of whether its inhibition could be a potential therapeutic intervention for these patients. Brain specimens of 23 SEGAs, 6 CTs, 20 FCD2Bs and 17 controls were analysed via immunohistochemistry to characterise EGFR expression, cell proliferation (via Mib1) and mTOR signalling. In a cell-based assay using primary patient-derived cells (CT n= 1, FCD2B n= 1 and SEGA n= 4), the effects of afatinib and everolimus on cell proliferation and cell viability were observed. EGFR overexpression was observed in histological sections of SEGA, CT and FCD2B patients. Both everolimus and afatinib decreased the proliferation and viability in primary SEGA, tuber and FCD2B cells. Our study demonstrates that EGFR suppression might be an effective alternative treatment option for SEGAs and tubers, as well as other mTOR-associated malformations of cortical development, including FCD2B.

The Association of the Epidermal Growth Factor Receptor (EGFR) Immunoexpression With Prognostic Parameters in Adenocarcinoma Patients Receiving Neoadjuvant Treatment.

The epidermal growth factor receptor (EGFR) expression is considered to play an essential role in the pathogenesis of colorectal adenocarcinoma. This study assessed the expression and predictive/prognostic value of EGFR expression in pre-op biopsy and post-op resection specimens in patients receiving neoadjuvant radiotherapy/neoadjuvant chemoradiotherapy (NRT/NCRT). Thirty-four consecutive patients were included in this study. The association between the prognostic features and EGFR immunohistochemical expression was analyzed in pre- (n=34) and post-treatment (n=22) tissue samples in cases with available tissue blocks. Of 34, 23 (67.6%) were men. The median age was 60.50 ± 10.69 (range, 31-84) years. EGFR expression was detected in 88.2% of biopsy specimens and in 91.2% of surgical specimens. There was only slight agreement between pre-op and post-op EGFR expression scores (kappa value 0.11). There was no significant correlation between pre-op and post-op EGFR expression scores (p>0.05). Although pre-op EGFR positivity and higher pre-op EGFR scores seemed to indicate a worse prognosis, this association between pre-op EGFR expression and overall survival (OS) or disease-specific survival (DSS) did not reach statistical significance (p>0.05). The only case with a post-op EGFR score of three who died of the disease experienced local recurrence and had distant metastasis. In conclusion, EGFR positivity in pre-op biopsy samples seems to be associated with shorter survival, and increased EGFR expression in post-treatment resection specimens predicts aggressive behavior in patients with rectal adenocarcinoma who received NRT/NCRT. However, due to the molecular heterogeneity, EGFR expression status should be evaluated in resection specimens rather than in pre-op biopsy samples for optimal prognosis prediction.

Indoxyl sulfate contributes to colorectal cancer cell proliferation and increased EGFR expression by activating AhR and Akt.

Although patients with chronic kidney disease (CKD) have a higher risk of colorectal cancer (CRC) aggravation, the connection between these two diseases is not well understood. Recent studies have shown that both CKD and CRC aggravation are closely related to an increased abundance of indole-producing Fusobacterium nucleatum in the gut. The indole absorbed from the gut is eventually metabolized to indoxyl sulfate in the liver. Since indoxyl sulfate is involved not only in accelerating CKD progression but also in the initiation and development of its associated complications, the present study aimed to clarify whether indoxyl sulfate induces the proliferation of CRC cells. This study found that indoxyl sulfate induced the proliferation of CRC-derived HCT-116 cells by activating the aryl hydrocarbon receptor (AhR) and the proto-oncogene Akt. The AhR antagonist CH223191 and Akt inhibitor MK2206 suppressed indoxyl sulfate-induced proliferation of HCT-116 cells. We also found that indoxyl sulfate upregulated epidermal growth factor receptor (EGFR) expression, which is associated with poor prognosis of CRC, whereas CH223191 and MK2206 repressed EGFR expression. Furthermore, indoxyl sulfate increased the sensitivity of CRC cells to EGF by upregulating EGFR expression. These findings suggest that indoxyl sulfate may be an important link between CKD and CRC aggravation.