Expression Levels Of EGFR Research Articles

Expressions of ZNF436, β-catenin, EGFR, and CMTM5 in breast cancer and their clinical significances.

As the leading malignancy among women, breast cancer is a serious threat to the life and health of women. In this context, it is of particular importance that a proper therapeutic target be identified for breast cancer treatment. We collected the pathological tissues of 80 patients, with the view to discovering appropriate molecular targets for the treatment of breast cancer, this paper analyzes the expressions of ZNF436, β-catenin, EGFR and CMTM5 in breast cancer tissues, as well as their correlations with breast cancer in combination with the clinicopathologic characteristics of studied patients. Immunohistochemistry was utilized to detect the expression levels of ZNF436, β-catenin, EGFR and CMTM5 in cancerous and paracancerous tissues of breast cancer patients. The expression levels of ZNF436, β-Catenin and EGFR in breast cancer tissues were significantly greater than those in paracancerous tissues in this study (p<0.05), while CMTM5 was highly expressed in paracancerous tissues (p<0.05). Additionally, the correlation of the expressions of such indicators with the staging, differentiation and lymphatic metastasis of breast cancer, were also found to be statistically significant at the level p<0.05. The different expression levels of ZNF436, β-catenin, EGFR and CMTM5 in breast cancer and paracancerous tissues open up the possibility of utilizing them as molecular markers for breast cancer. These findings provide a theoretical basis for targeted molecular therapies for breast cancer, and hence carry a significant practical significance.

Analysis of CK5/6 and EGFR and Its Effect on Prognosis of Triple Negative Breast Cancer.

BackgroundTriple-negative breast cancer (TNBC) is considered to be higher grade, more aggressive and have a poorer prognosis than other types of breast cancer. Discover biomarkers in TNBC for risk stratification and treatments that improve prognosis are in dire need.MethodsClinical data of 195 patients with triple negative breast cancer confirmed by pathological examination and received neoadjuvant chemotherapy (NAC) were collected. The expression levels of EGFR and CK5/6 were measured before and after NAC, and the relationship between EGFR and CK5/6 expression and its effect on prognosis of chemotherapy was analyzed.ResultsThe overall response rate (ORR) was 86.2% and the pathological complete remission rate (pCR) was 29.2%. Univariate and multivariate logistic regression analysis showed that cT (clinical Tumor stages) stage was an independent factor affecting chemotherapy outcome. Multivariate Cox regression analysis showed pCR, chemotherapy effect, ypT, ypN, histological grades, and post- NAC expression of CK5/6 significantly affected prognosis. The prognosis of CK5/6-positive patients after NAC was worse than that of CK5/6-negative patients (p=0.036). Changes in CK5/6 and EGFR expression did not significantly affect the effect of chemotherapy, but changes from positive to negative expression of these two markers are associated with a tendency to improve prognosis.ConclusionFor late-stage triple negative breast cancer patients receiving NAC, patients who achieved pCR had a better prognosis than those with non- pCR. Patients with the change in expression of EGFR and CK5/6 from positive to negative after neoadjuvant chemotherapy predicted a better prognosis than the change from negative to positive group.

Targeted multiplex proteomics (TMP) and genomics of early-onset colorectal cancer (EO-CRC).

97 Background: The incidence and mortality of early-onset colorectal cancer (EO-CRC) is on the rise. Consequently, there is an urgent unmet need to better understand their unique tumor biology to expand therapeutic options and improve clinical outcomes. Methods: Exploratory Targeted multiplex proteomics (TMP) and targeted 648 gene panel was performed on specimens from 35 patients with resected colon cancer diagnosed at age &lt; = 40 years. TMP panel consisted of 72 proteins involved in differentiation, tumorigenesis, and response to chemotherapy, targeted therapy, and immunotherapy. Clinicopathologic and genomic data were also collected. Results: The median age of diagnosis was 33 years. The cohort included 15 male and 20 female patients. 20 (57%) had left-sided tumors and 6 (17%) had stage IV disease. Notable genomic alterations included mutations in: BRAF V600E (2/35); RAS (15/35); PIK3CA exon 9 or 20 (5/35); and ERBB2 (2/35). One patient exhibited ERBB2 amplification. 9/35 tumors were MSI-H. TMP analysis revealed overexpression of chemotherapy resistance proteins in several patients: ALDH1A1:16/35; ERCC1:1/35; GART:26/35; MDR1:9/35; MGMT:5/35; RRM1:6/35; TUBB3:1/35; TYMS:2/35; XRCC1:11/35. In contrast, some tumors exhibited elevated biomarkers of chemosensitivity: hENT1:8/35; DHFR:12/35; TYMP:15/35; OPRT:8/35; SLFN11:1/35; TLE:11/35; TOPO1:12/35; TOPO2A:1/35. Protein targets of cell signaling pathways were overexpressed in a number of tumors: CAT:16/35; CAV-1: 6/35; CBL:2/35; E-Cadherin: 19/35; HSP90A:16/35; HSP90B:18/35; MET:5/35; NQO1:18/35; paxillin:4/35; SRC:21/35; STAT3:11/35. Regarding EGFR and KRAS, none of the tumors exhibited elevated protein expression level. Furthermore, RAS mutational status did not correlate with the level of EGFR or KRAS protein expression. Antibody drug conjugate biomarkers were observed. HER2 overexpression was noted in one patient who had a confirmed ERBB2 amplification. Regarding immunotherapy targets, PDL-1 protein was not overexpressed in any tumor, whereas MSLN and TROP2 were elevated in 1/35 and 2/35 patients, respectively. Conclusions: TMP analysis of EO-CRC patients revealed marked heterogeneity in the expression of proteins involved in differentiation, tumorigenesis, and response to chemotherapy, targeted therapy, and immunotherapy. Differential protein expression may provide insight into therapeutic vulnerabilities for EO-CRC. Furthermore, the discordance between detected genomic alterations and protein expression levels highlights the complementary nature of genomic sequencing and TMP analysis.

Is Tumor Cell Specificity Distinct from Tumor Selectivity In Vivo?: A Quantitative NIR Molecular Imaging Analysis of Nanoliposome Targeting.

The significance and ability for receptor targeted nanoliposomes (tNLs) to bind to their molecular targets in solid tumors in vivo has been questioned, particularly as the efficiency of their tumor accumulation and selectivity is not always predictive of their efficacy or molecular specificity. This study presents, for the first time, in situ NIR molecular imaging-based quantitation of the in vivo specificity of tNLs for their target receptors, as opposed to tumor selectivity, which includes influences of enhanced tumor permeability and retention. Results show that neither tumor delivery nor selectivity (tumor-to-normal ratio) of cetuximab and IRDye conjugated tNLs correlate with EGFR expression in U251, U87 and 9L tumors, and in fact underrepresent their imaging-derived molecular specificity by up to 94.2%. Conversely, their in vivo specificity, which we quantify as the concentration of tNL-reported tumor EGFR provided by NIR molecular imaging, correlates positively with EGFR expression levels in vitro and ex vivo (Pearson's r= 0.92 and 0.96, respectively). This study provides a unique opportunity to address the problematic disconnect between tNL synthesis and in vivo specificity. The findings encourage their continued adoption as platforms for precision medicine, and facilitates intelligent synthesis and patient customization in order to improve safety profiles and therapeutic outcomes.

Age-associated changes in the transcriptomes of non-cultured adipose-derived stem cells from young and old mice assessed via single-cell transcriptome analysis.

Adipose-derived stem cells (ASCs) exhibit self-renewal and pluripotency. The differentiation potency of ASCs has been reported to deteriorate with aging; however, relevant studies used ASCs that were isolated and subcultured several times. It is still unclear whether subcultured ASCs accurately reflect the in vivo state. To address this question, we used freshly isolated stromal vascular fractions (SVFs) and performed comprehensive single-cell transcriptome analysis. In this study, we identified three cell populations as putative ASC candidates in SVFs and three novel ASC-related genes: Adamts7, Snai2, and Tgfbr1, that are reported to be negative regulators of cell differentiation. Moreover, we identified age-associated high gene expression levels of Adamts7, Egfr, and Igfbp4 in the earliest differentiation stage of ASCs. These results suggest that aging may make it impossible to maintain the stringency of the regulation of the expression of some genes related to ASC differentiation.

ADAMTSL5 is an epigenetically activated gene underlying tumorigenesis and drug resistance in hepatocellular carcinoma

The tumour microenvironment shapes tumour growth through cellular communications that include both direct interactions and secreted factors. The aim of this study was to characterize the impact of the secreted glycoprotein ADAMTSL5, whose role in cancer has not been previously investigated, on hepatocellular carcinoma (HCC). ADAMTSL5 methylation status was evaluated through bisulfite sequencing, and publicly available data analysis. ADAMTSL5 RNA and protein expression were assessed in mouse models and HCC patient samples and compared to data from published datasets. Functional studies, including association of ADAMTSL5 depletion with responsiveness to clinically relevant drugs, were performed in cellular and invivo models. Molecular alterations associated with ADAMTSL5 targeting were determined using proteomics, biochemistry, and reverse-transcription quantitative PCR. Methylome analysis revealed hypermethylated gene body CpG islands at the ADAMTSL5 locus in both mouse and human HCC, correlating with higher ADAMTSL5 expression. ADAMTSL5 targeting interfered with tumorigenic properties of HCC cells invitro and invivo, whereas ADAMTSL5 overexpression conferred tumorigenicity to pre-tumoural hepatocytes sensitized to transformation by a modest level of MET receptor expression. Mechanistically, ADAMTSL5 abrogation led to a reduction of several oncogenic inputs relevant to HCC, including reduced expression and/or phosphorylation levels of receptor tyrosine kinases MET, EGFR, PDGFRβ, IGF1Rβ, or FGFR4. This phenotype was associated with significantly increased sensitivity of HCC cells to clinically relevant drugs, namely sorafenib, lenvatinib, and regorafenib. Moreover, ADAMTSL5 depletion drastically increased expression of AXL, accompanied by a sensitization to bemcentinib. Our results point to a role for ADAMTSL5 in maintaining the function of key oncogenic signalling pathways, suggesting that it may act as a master regulator of tumorigenicity and drug resistance in HCC. The environment of cancer cells has profound effects on establishment, progression, and response of a tumour to treatment. Herein, we show that ADAMTSL5, a protein secreted by liver cancer cells and overlooked in cancer so far, is increased in this tumour type, is necessary for tumour formation and supports drug resistance. Adamtsl5 removal conferred sensitivity of liver cancer cells to drugs used in current treatment. This suggests ADAMTSL5 as a potential marker in liver cancer as well as a possible drug target.

The Clinical Study of Multigene Combination Test to Guide Chemotherapy Combined with Targeted Therapy in Patients with Advanced Gastrointestinal Tumors

Objective: To study the clinical effects of multigene combination test to guide chemotherapy combined with targeted therapy in patients with advanced gastrointestinal tumors. Methods: The samples were selected from 60 patients with advanced gastrointestinal tumors admitted to our hospital from March 2019 to July 2020, and were divided into a study group and a control group using a random number table model; patients in the control group did not undergo genetic testing and FOLLOX4+PD-1 chemotherapy, while patients in the study group underwent TYMS, ERCC1, EGFR, and KRAS and VEGF gene expression levels test, and the sensitive treatment plan was determined based on the test results, and the clinical indexes were compared between the two groups. Results: By comparing the total effective rate, survival time, and time to disease progression of chemotherapy in the two groups, the study group has a significant advantage (P&lt;0.05). Conclusion: The combination of chemotherapy and targeted therapy for advanced gastrointestinal tumor patients can improve the efficiency of chemotherapy and prolong the time of disease progression and survival, which is worthy of comprehensive promotion.

Exploration in the Mechanism of Kaempferol for the Treatment of Gastric Cancer Based on Network Pharmacology.

Background Kaempferol is a natural polyphenol in lots of Chinese herbs, which has shown promising treatment for gastric cancer (GC). However, the molecular mechanisms of its action have not been systematically revealed yet. In this work, a network pharmacology approach was used to elucidate the potential mechanisms of kaempferol in the treatment of GC. Methods The kaempferol was input into the PharmMapper and SwissTargetPrediction database to get its targets, and the targets of GC were obtained by retrieving the Online Mendelian Inheritance in Man (OMIM) database, MalaCards database, Therapeutic Target Database (TTD), and Coolgen database. The molecular docking was performed to assess the interactions between kaempferol and these targets. Next, the overlap targets of kaempferol and GC were identified for GO and KEGG enrichment analyses. Afterward, a protein-protein interaction (PPI) network was constructed to get the hub targets, and the expression and overall survival analysis of the hub target were investigated. Finally, the overall survival (OS) analysis of hub targets was performed using the Kaplan-Meier Plotter online tool. Results A total of 990 genes related to GC and 10 overlapping genes were determined through matching the 24 potential targets of kaempferol with disease-associated genes. The result of molecular docking indicated that kaempferol can bind with these hub targets with good binding scores. These targets were further mapped to 140 GO biological process terms and 11 remarkable pathways. In the PPI network analysis, 3 key targets were identified, including ESR1, EGFR, and SRC. The mRNA and protein expression levels of EGFR and SRC were obviously higher in GC tissues. High expression of these targets was related to poor OS in GC patients. Conclusions This study provided a novel approach to reveal the therapeutic mechanisms of kaempferol on GC, which will ease the future clinical application of kaempferol in the treatment of GC.

LncRNA TSLNC8 synergizes with EGFR inhibitor osimertinib to inhibit lung cancer tumorigenesis by blocking the EGFR-STAT3 pathway

ABSTRACT The roles of lncRNA TSLNC8 and its synergetic effects with osimertinib remain unknown in lung cancer. qRT-PCR or western blotting was performed to determine the expression levels of TSLNC8, EGFR and STAT3. Colony formation and MTT assays were used to evaluate cell proliferation. Transwell and wound healing assays were performed to assess migration and invasion abilities. Flow cytometry with Annexin V/PI staining was used to detect changes in cell apoptosis. Nude mice subcutaneous tumor model was constructed and used for validating the effects of TSLNC8 and osimertinib in vivo. Expression of TSLNC8 was down-regulated in clinical lung cancer tissues and cell lines. TSLNC8 overexpression or osimertinib administration led to promotion of apoptosis and inhibition of cell proliferation, migration and invasion, as well as deactivation of the EGFR-STAT3 pathway, whereas TSLNC8 knockdown had opposite effects. Moreover, the above effects of osimertinib were remarkably enhanced by TSLNC8 overexpression and inhibited by TSLNC8 knockdown, respectively. Meanwhile, the effects of TSLNC8 overexpression were reversed by STAT3 activation or EGFR overexpression. In the animal model, combination of TSLNC8 overexpression and osimertinib administration resulted in efficient suppression of tumor growth. In this study, we revealed a TSLNC8-EGFR-STAT3 signaling axis in lung cancer, and TSLNC8 overexpression significantly enhanced the anti-tumor effects of osimertinib via inhibiting EGFR-STAT3 signaling.

Soluble EGFR, a hepatokine, and adipsin, an adipokine, are biomarkers correlated with distinct aspects of insulin resistance in type 2 diabetes subjects

BackgroundInsulin resistance can occur in all metabolic organs including the liver, adipose tissue, and skeletal muscles. Circulating soluble epidermal growth factor receptor (soluble EGFR) and adipsin levels are altered in obese diabetic mice and are possibly correlated with insulin resistance in both mice and humans. Here, we investigated the significance of soluble EGFR and adipsin as biomarkers for insulin resistance in Japanese subjects with type 2 diabetes.MethodsWe measured the soluble EGFR and adipsin levels in sera from 47 non-diabetic subjects and 106 subjects with type 2 diabetes using enzyme-linked immunosorbent assays (ELISAs) and analyzed the correlations between the soluble EGFR or adipsin levels and metabolic parameters in type 2 diabetes subjects. We also measured the gene expression levels of Egfr and Cfd (adipsin) in the liver, adipose tissue, and skeletal muscle in mice with/without obesity or diabetes.ResultsThe soluble EGFR levels were correlated with the fasting blood glucose level (P = 0.010), HOMA-IR (P = 0.035), HbA1c level (P = 0.007), HDL-cholesterol level (P = 0.044), and FIB-4 index (P = 0.017) after adjustments for age, sex, and total cholesterol levels. These factors are known to be related to hepatic insulin resistance. The serum adipsin levels were correlated with BMI (P < 0.001), waist circumference (P < 0.001), fasting serum insulin level (P = 0.001), HOMA-IR (P = 0.009), CPR-index (P = 0.045), and FIB-4 index (P = 0.007) after adjustments for age, sex and eGFR levels. Abdominal adiposity leads to the potentiation of these factors. The expression of Egfr was abundant in the liver, while Cfd was predominantly expressed in adipose tissue in mice.ConclusionsSoluble EGFR, a hepatokine, is correlated with insulin resistance in the liver, while adipsin, an adipokine, is associated with adipose insulin resistance.Trial registration: UMIN Clinical Trials Registry (www.umin.ac.jp), UMIN000020474. Registered 8 January 2016.

Bioinformatic analysis reveals the molecular targets of tangeretin in overcoming the resistance of breast cancer to tamoxifen

The positive outcome of tamoxifen is reduced because of the emergence of intrinsic and acquired resistance that triggers relapse and metastasis; as such, a combination therapy containing tamoxifen should be developed to improve its effectiveness in breast cancer therapy. This study was performed via an integrative bioinformatic approach to explore tangeretin, a citrus flavonoid and potential molecular target in overcoming the resistance of breast cancer to tamoxifen (TT). Six tangeretin targets, namely, AKR1C1, TNKS2, BACE1, GSK3B, EGFR, and IGF1R, were obtained, and they showed potential for application in overcoming the resistance of breast cancer to tamoxifen. The Kaplan–Meier curve revealed that the prognosis of patients with a low mRNA expression of IGF1R was significantly worse than that of the opposite group. The validation of the gene expression with GEPIA indicated that the mRNA expression levels of AKR1C1 and EGFR were significantly higher in patients with breast cancer than in the opposite group. The mRNA levels of GSK3B and EGFR were higher in recurrent breast cancer cells treated with tamoxifen than in nonrecurrent breast cancer cells. The mRNA level of TNKS2 in recurrent breast cancer cells treated with tamoxifen was lower than that in nonrecurrent breast cancer cells. This study highlighted AKR1C1, TNKS2, BACE1, GSK3B, EGFR, and IGF1R as the six potential tangeretin targets in overcoming the resistance of breast cancer to tamoxifen. However, our results should be further validated with in vitro and in vivo studies.

Genes Involved in the PD-L1 Pathway Might Associate with Radiosensitivity of Patients with Gastric Cancer.

The PD-1/PD-L1 pathway plays an important role in the treatment of cancers as immune checkpoint. However, the association of genes involved in the PD-L1 pathway and radiosensitivity of gastric cancer has not been fully characterized. This study aims to explore the relationship between the expression levels of genes involved in the PD-L1 pathway and radiosensitivity for gastric cancer patients. A total of 367 patients with clinical survival information and radiotherapy information were obtained in The Cancer Genome Atlas (TCGA). Genes involved in the PD-L1 pathway were categorized into high and low expression level groups according to the median value. The Cox proportional hazards model was used to find the association between gene expression level and radiosensitivity. The results show that high expression levels of CD274, EGFR, RAF1, RPS6KB1, PIK3CA, MTOR, CHUK, NFKB1, TRAF6, FOS, NFATC1, and HIF1A were associated with radiosensitivity of gastric cancer. While low expression level of HRAS was also associated with radiosensitivity in gastric cancer. The rates of a new tumor event and disease progression were lower for radiosensitivity patients than other patients. The relationship between the expression level of CD274 and other genes involved in the PD-L1 pathway is significant. GO (Gene Ontology) analysis shows that the biological process of 13 genes was mainly related to innate immune response activating the cell surface receptor signaling pathway. KEGG analysis demonstrated that 13 genes in gastric cancer are mainly related to the PD-L1 expression and PD-1 checkpoint pathway in cancer. The correlation between the expression level of CD274 and other genes involved in the PD-L1 pathway is significant. The present study offered more evidence for using PD-L1 and genes involved in the PD-L1 pathway as potential biomarkers to predict radiosensitive patients with gastric cancer.

Abstract 3813: Activation of EGFR induces loss of primary cilia in oral mucosa carcinogenesis

Abstract Objective: Primary cilia are evolutionally conserved cell structures involving multiple cell functions by sensing extracellular signals. Loss of primary cilia is frequently observed in various cancer types, suggesting that the absence of this organelle may promote tumorigenesis. However, little is known about the role of primary cilia in oral premalignant lesions and oral squamous cell carcinoma (OSCC). Materials and Methods: Immunofluosense staining was carried out to detect the incidence of primary cilia in every stages of oral carcinogenesis from normal to OSCC. Immunohistochemical analysis was used for validating the correlation between the ciliary incidence and the expression level of EGFR in the oral carcinogenesis. Furthermore, the change of primary cilia was detected by activating and inhibiting the EGFR pathway activity in vitro. Results: A significant decrease in the percentage of ciliated cells was found on both oral leukoplakia (OLK), as well as OSCC tissues, compared to normal oral mucosa epithelium, and this loss of cilia was independent of the increased proliferative index. A parallel increase of EGFR activity was observed in OLK and OSCC tissues. In addition, EGF stimulation induced obvious primary cilia absorption, whereas inhibition of EGFR by gefitinib significantly restored cilia formation in vitro. We further found that the activation of EGFR resulted in the phosphorylation of AURKA, a pivotal kinase promoting disassembly of primary cilia. Conclusion: EGFR-AURKA pathway might be a critical regulator of ciliary loss in the carcinogenesis of oral mucosa. This may provide insight into the development of new therapeutic strategies to prevent oral premalignant lesions from becoming malignant. Citation Format: Fengg yin, Zihao Wei, Jing Li, Liang Xie, Qianming Chen. Activation of EGFR induces loss of primary cilia in oral mucosa carcinogenesis [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3813.

Abstract 4490: MUC3A induces PD-L1 and reduces tyrosine kinase inhibitor effects in EGFR-mutant non-small cell lung cancer

Abstract Objective: Lung cancer is one of the leading causes of cancer-related mortality in the world, and non-small cell lung cancer (NSCLC) accounts for approximately 85% of all lung cancers. With the emergence of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), the prognosis of adenocarcinoma patients with specific EGFR mutations has been significantly improved. Unfortunately, despite the success of EGFR-TKIs in NSCLC patients, almost all cases eventually recrudesce after a median of 10 months. Therapeutic antibodies blocking programmed death-ligand 1 (PD-L1) brought striking regression of NSCLC. However, only 20% patients response to the αPD-L1 therapy. Activation of EGFR signaling pathway was also reported to induce PD-L1 expression in NSCLC. MUC3A is a transmembrane mucin with 2 epidermal growth factor (EGF)-like domains in the extracellular segment. This work aimed to investigate the effects of MUC3A on PD-L1 expression and EGFR-TKIs sensitivity in EFGR-mutant NSCLC. Methods: Expression levels of MUC3A and PD-L1 in tissue microarray of 92 patients' lung tumor samples were measured by immunohistochemistry. Data of lung cancer were downloaded from the TCGA database, and the correlation of PD-L1 expression between EGFR wild type and mutation in lung cancer patients was analyzed. H1975 and PC-9 cells were infected with lentiviral vectors to downregulate MUC3A. The expression pattern of PD-L1 in NSCLC cell lines was detected by qRT-PCR and flow cytometry. Cell proliferation was assessed with CCK-8. Cell apoptosis was examined by flow cytometry. Immunoblotting was used to identify molecular markers of signaling pathways. An xenograft nude mouse transplantation model was established to examine the effects of MUC3A and EGFR-TKIs on tumorigenesis in vivo. The expression levels of MUC3A, EGFR and PD-L1 in harvested tumors were measured by immunohistochemistry. Results: Tissue microarray of 92 patients' lung tumor samples indicated that high levels of MUC3A were positively correlated with poor prognosis and PD-L1 expression. In the TCGA database, the levels of PD-L1 were independent of the protein levels of EGFR, but correlated with EGFR mutation. Our results showed that induction of PD-L1 by EGF stimulation was only detected in EGFR-mutated NSCLC cell lines, such as H1975 and PC-9, but not in H1299 and H460. Knockdown of MUC3A in H1975 and PC-9 reduced PD-L1 expression, as well as PI3K/Akt and MAPK pathways. In addition, MUC3A deficiency potentiated gefitinib and AZD-9291-induced growth inhibition in PC-9 and H1975 cells by downregulating proliferation and inducing apoptosis. More interestingly, knockdown of MUC3A decreased EGFR protein levels, but not mRNA levels. Our findings suggested that MUC3A deficiency improved EGFR-mutated NSCLC sensitivity to tyrosine kinase inhibitors via increasing EGFR protein stability and decreasing PD-L1 expression through PI3K/Akt and MAPK pathways. Mice inoculated with MUC3A deficiency tumor cells treated with AZD-9291 had the fastest tumor regression and delayed relapse. Conclusions: The transmembrane mucin MUC3A increased EGFR stability. MUC3A induced PD-L1 and reduced tyrosine kinase inhibitor effects via EGFR modulation in NSCLC, suggesting potential implications for a novel immunotherapeutic approach. Citation Format: Yuan Luo, Shijing Ma, Yingming Sun, Shan Peng, Yan Gong, Conghua Xie. MUC3A induces PD-L1 and reduces tyrosine kinase inhibitor effects in EGFR-mutant non-small cell lung cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4490.

Abstract 2780: In vivo quantitative molecular imaging for receptor-specific contrast and image guided surgery of glioblastoma

Abstract Quantitative, noninvasive imaging utilizing the full potential of antibody targeted nanomedicines has recently emerged as a new paradigm in cancer therapeutics. However, the specificity of these nanomedicines to the molecular targets in in vivo is much controversial. We have leveraged a molecular-specific approach for the simultaneous imaging and quantitation of in vivo EGFR expression levels, using NIR-activable cetuximab targeted nanomedicine. Using quantitative molecular imaging, the EGFR specificity of these targeted nanomedicines is measured, following i.v. administration in glioblastoma tumors bearing mice. For the first time we demonstrate, that in vivo specificity of ligand targeted nanomedicines correlates positively with cellular expression levels of EGFR established by flow cytometry (Pearson's r = 0.93, p &amp;lt; 0.0003).Importantly, we show that the EGFR concentrations in glioblastoma (with varying expressions of EGFR) closely match with those previously derived from dual-reporter imaging using fluorescent conjugates. This first demonstration of non-invasive quantitation of targeted nanomedicine binding introduces an unexplored approach to leverage targeted nanomedicines as a critical component in the design and validation process of cancer therapeutics. Such an informed methodology promises to expedite translation and minimize failures that often occur after substantial investment. Citation Format: Shazia Bano. In vivo quantitative molecular imaging for receptor-specific contrast and image guided surgery of glioblastoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2780.

Targeting Hypoxia Sensitizes TNBC to Cisplatin and Promotes Inhibition of Both Bulk and Cancer Stem Cells.

Development of targeted therapies for triple-negative breast cancer (TNBC) is an unmet medical need. Cisplatin has demonstrated its promising potential for the treatment of TNBC in clinical trials; however, cisplatin treatment is associated with hypoxia that, in turn, promotes cancer stem cell (CSC) enrichment and drug resistance. Therapeutic approaches to attenuate this may lead to increased cisplatin efficacy in the clinic for the treatment of TNBC. In this report we analyzed clinical datasets of TNBC and found that TNBC patients possessed higher levels of EGFR and hypoxia gene expression. A similar expression pattern was also observed in cisplatin-resistant ovarian cancer cells. We, thus, developed a new therapeutic approach to inhibit EGFR and hypoxia by combination treatment with metformin and gefitinib that sensitized TNBC cells to cisplatin and led to the inhibition of both CD44+/CD24− and ALDH+ CSCs. We demonstrated a similar inhibition efficacy on organotypic cultures of TNBC patient samples ex vivo. Since these drugs have already been used frequently in the clinic; this study illustrates a novel, clinically translatable therapeutic approach to treat patients with TNBC.

Nimotuzumab Combined With Irradiation Enhances the Inhibition to the HPV16 E6-Promoted Growth of Cervical Squamous Cell Carcinoma.

Human papillomavirus (HPV) 16 E6 has been proved to increase the radiosensitivity and lead to the EGFR overexpression in cervical cancer cells. In this study, to investigate the inhibition of nimotuzumab-mediated EGFR blockade combined with radiotherapy, we established a C33A cervical squamous cell line overexpressed HPV16-E6 and a nude mouse model bearing these cell lines. The CCK-8 assay was used to detect the effects of various treatments on the proliferation of C33A cells. Flow cytometry was used to detect the rates of apoptosis and cell cycle arrest. Gene transcription and protein expression were detected by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot, respectively. Immunohistochemical staining was used to evaluate protein expression in tumor tissue. We revealed that E6-overexpressing C33A cells grew faster and were more sensitive to radiotherapy than control cells in vitro and in vivo. The expression levels of EGFR, as well as those of downstream signaling molecules AKT and ERK 1/2, were significantly upregulated in C33A cells that overexpressed E6. We observed that nimotuzumab combined with radiotherapy could enhance the inhibition of C33A cell growth induced by E6, both in vitro and in vivo. We also observed enhanced effect after combination on G2/M cell cycle arrest and apoptosis in E6-overexpressing C33A cells. Furthermore, the combined therapy of nimotuzumab and radiation remarkably reduced the protein expression levels of EGFR, AKT, ERK 1/2 in vitro, and in vivo. In conclusion, HPV16 E6 expression is positively correlated with levels of EGFR, AKT, and ERK 1/2 protein expression. The combined treatment with nimotuzumab and radiotherapy to enhance radiosensitivity in E6-positive cervical squamous cell carcinoma was related to enhanced G2/M cell cycle arrest and caspase-related apoptosis.

Study of EGFR expression in tumor tissue in patients with locally advanced oral cavity cancer receiving cetuximab therapy

Introduction:Squamous cell carcinoma of the oral cavity is one of the most common head and neck cancers with an aggressive course and high mortality rates.The aimof the study was to determine the EGFR expression levels in tumor tissues in patients with squamous cell carcinoma of the tongue and oral mucosa depending on the efficacy of the therapy.Material and methods:The study included 60 patients with squamous cell carcinoma of the tongue and oral mucosa T3-4N0-1M0. The main group included 30 patients receiving chemotherapy (cisplatin/fluorouracil) in combination with targeted therapy with cetuximab. The control group included 30 patients receiving chemotherapy without cetuximab. Both groups were divided into two subgroups: sensitive and resistant.Results:In treatment-resistant patients of the main group with cetuximab, the average EGFR expression was twice lower than the initial levels (p = 0.0080) and 1.7 times higher than in treatment-resistant patients of the control group (p = 0.0157). In treatment-sensitive patients, the average EGFR expression was 19.8 times lower (p = 0.0020) than initial values and 14.9 times higher (p = 0.0067) than in treatment-sensitive controls.Conclusions:A natural decrease in the EGFR expression in tumor tissues due to the targeted therapy was revealed. However, some patients were resistant to cetuximab, which dictates the need to search for predictors of targeted therapy efficacy in patients with locally advanced squamous cell carcinoma of the tongue and oral mucosa.

Influence of antigen density and immunosuppressive factors on tumor-targeted costimulation with antibody-fusion proteins and bispecific antibody-mediated T cell response

Target expression heterogeneity and the presence of an immunosuppressive microenvironment can hamper severely the efficiency of immunotherapeutic approaches. We have analyzed the potential to encounter and overcome such conditions by a combinatory two-target approach involving a bispecific antibody retargeting T cells to tumor cells and tumor-directed antibody-fusion proteins with costimulatory members of the B7 and TNF superfamily. Targeting the tumor-associated antigens EpCAM and EGFR with the bispecific antibody and costimulatory fusion proteins, respectively, we analyzed the impact of target expression and the influence of the immunosuppressive factors IDO, IL-10, TGF-β, PD-1 and CTLA-4 on the targeting-mediated stimulation of T cells. Here, suboptimal activity of the bispecific antibody at diverse EpCAM expression levels could be effectively enhanced by targeting-mediated costimulation by B7.1, 4-1BBL and OX40L in a broad range of EGFR expression levels. Furthermore, the benefit of combined costimulation by B7.1/4-1BBL and 4-1BBL/OX40L was demonstrated. In addition, the expression of immunosuppressive factors was shown in all co-culture settings, where blocking of prominent factors led to synergistic effects with combined costimulation. Thus, targeting-mediated costimulation showed general promise for a broad application covering diverse target expression levels, with the option for further selective enhancement by the identification and blockade of main immunosuppressive factors of the particular tumor environment.

An analysis of clinicopathological characteristics and prognosis on hepatoid adenocarcinoma of stomach.

e16558 Background: Hepatoid adenocarcinoma of the stomach(HAS) is a rare type of gastric adenocarcinoma(GAC). At present, histopathology is the gold standard for the diagnosis of HAS, however, HAS is easy to be missed diagnosis, and lack of a perfect diagnosis system and effective treatment strategy. In this research, clinical pathological features will be analyzed to improve the diagnostic system, judge prognosis and provide clues for exploration of pathogenesis and targeted therapy of HAS. Methods: 576 cases including 5 confirmed patients with HAS were enrolled onto this study from 1320 patients with GAC. 10 cases of HAS were diagnosed by the second histopathological examination from the other 571 enrolled cases. 30 cases from the remaining 561 enrolled patients were randomly selected as the control group. The information of the two group cases were completed by collecting the existing case data, detecting the missed immunohistochemical indicators and telephone follow-up. The clinicopathological features of the two group cases were compared, and the treatment and prognosis of 15 HAS cases were analyzed. Results: In this study, 15 cases of HAS were found in 576 patients with GAC, including 5 cases from the 1st pathological diagnosis and 10 cases from the 2nd pathological diagnosis. There was no significant difference in age, gender, HP positive rate, serum CEA or CA19-9 level, tumor size, TNM stage, tumor invasion depth, lymph node invasion, distant metastasis rate, differentiation degree, nerve/vascular invasion, and Ki-67 expression level between the two groups( P&gt; 0.05). Compared with the control group, the serum AFP level, and the expression level of GPC3, AFP, EGFR and VEGF protein of patients in HAS group were significantly high, as well as the patients in the HAS group were more likely to develop liver metastasis( P&lt; 0.05). The mOS was 12 mo vs 42 mo for HAS group vs control group( P&lt; 0.05). Multivariate analysis showed immunohistochemical AFP staining intensity was an independent risk factor for prognosis of HAS. Conclusions: As a special type of GAC, HAS is prone to developing liver metastasis with poor prognosis. Based on the higher missed diagnosis rate of HAS, it is suggested to make 2nd cancer histopathological diagnosis including immunohistochemical detection of AFP and GPC3 for GAC patients with significantly increased serum AFP level. The intensity of immunohistochemical AFP staining is an independent risk factor for the prognosis of patients with HAS. VEGF, EGFR and PD-1 / PDL-1 may be potential therapeutic targets of HAS, which is worth further study.