The epidermal growth factor receptor pathway: a model for targeted therapy

miR-582-5p inhibits migration and chemo-resistant capabilities of colorectal cancer cells by targeting TNKS2

BACKGROUND

Metastasis and chemo-resistance are still important factors that limit the overall efficacy of colorectal cancer treatment. Understanding the detailed molecular mechanism and identifying potential biomarkers are of great value in prognosis prediction and risk stratification.

OBJECTIVE

We investigated the role of miR-582-5p in colorectal cancer pathogenesis, progression and chemo-resistance. Furthermore, we explored the underlying molecular mechanism of miR-582-5p in modulation of malignant behaviors of colorectal cancer cells.

METHODS

Clinical samples and colorectal cancer cell lines were applied to explore miR-582-5p expression level and its significance on tumor cell metastasis and chemo-resistance. Transwell study and cellular survivability study were performed to explore the influences of miR-582-5p expression modulation on tumor cell chemo-resistance and invasion/migration. Dual-luciferase reporter gene assay was conducted to explore the influences of miR-582-5p on its target gene TNKS2.

RESULTS

Colorectal cancer patients with lymph node or distal organ metastatic diseases exhibited significantly lower level of miR-582-5p. In vitro studies have indicated that miR-582-5p inhibition significantly increased migration and chemo-resistant capabilities of tumor cells. And dual-luciferase reporter gene assay demonstrated that miR-582-5p exhibited its influences on the biological behavior of tumor cells by targeting TNKS2.

CONCLUSIONS

Our study demonstrated for the first time that miR-582-5p played an important role for colorectal tumor cell metastasis and chemo-resistance. Our research also indicated that miR-582-5p and its target gene TNKS2 could be novel biomarkers for metastatic disease prediction, overall prognosis evaluation, as well as potential therapeutic target for colorectal cancer patients.

Preclinical evaluation of AFM24, a novel CD16A-specific innate immune cell engager targeting EGFR-positive tumors

Epidermal growth factor receptor (EGFR)-targeted cancer therapy such as anti-EGFR monoclonal antibodies and tyrosine kinase inhibitors have demonstrated clinical efficacy. However, there remains a medical need addressing limitations of these therapies, which include a narrow therapeutic window mainly due to skin and organ toxicity, and primary and secondary resistance mechanisms of the EGFR-signaling cascade (e.g., RAS-mutated colorectal cancer). Using the redirected optimized cell killing (ROCK®) antibody platform, we have developed AFM24, a novel bispecific, IgG₁-scFv fusion antibody targeting CD16A on innate immune cells, and EGFR on tumor cells. We herein demonstrate binding of AFM24 to CD16A on natural killer (NK) cells and macrophages with K_D values in the low nanomolar range and to various EGFR-expressing tumor cells. AFM24 was highly potent and effective for antibody-dependent cell-mediated cytotoxicity via NK cells, and also mediated antibody-dependent cellular phagocytosis via macrophages in vitro. Importantly, AFM24 was effective toward a variety of EGFR-expressing tumor cells, regardless of EGFR expression level and KRAS/BRAF mutational status. In vivo, AFM24 was well tolerated up to the highest dose (75 mg/kg) when administered to cynomolgus monkeys once weekly for 28 days. Notably, skin and other toxicities were not observed. A transient elevation of interleukin-6 levels was detected at all dose levels, 2-4 hours post-dose, which returned to baseline levels after 24 hours. These results emphasize the promise of bispecific innate cell engagers as an alternative cancer therapy and demonstrate the potential for AFM24 to effectively target tumors expressing varying levels of EGFR, regardless of their mutational status.Abbreviations: ADA: antidrug antibody; ADCC: antibody-dependent cell-mediated cytotoxicity; ADCP: antibody-dependent cellular phagocytosis; AUC: area under the curve; CAR: chimeric-antigen receptor; CD: Cluster of differentiation; CRC :colorectal cancer; ECD: extracellular domain; EGF: epidermal growth factorEGFR epidermal growth factor receptor; ELISA: enzyme-linked immunosorbent assay; FACS: fluorescence-activated cell sorting; Fc: fragment, crystallizableFv variable fragment; HNSCC: head and neck squamous carcinomaIL interleukinm; Ab monoclonal antibody; MOA: mechanism of action; NK :natural killer; NSCLC: non-small cell lung cancer; PBMC: peripheral blood mononuclear cell; PBS: phosphate-buffered saline; PD: pharmacodynamic; ROCK: redirected optimized cell killing; RSV: respiratory syncytial virus; SABC: specific antibody binding capacity; SD: standard deviation; TAM: tumor-associated macrophage; TKI: tyrosine kinase inhibitor; WT: wildtype.

Primary metabolic tumor volume from 18F-FDG PET/CT associated with epidermal growth factor receptor mutation in lung adenocarcinoma patients

PURPOSE

To explore the potential parameters from F-FDG PET/CT that might be associated with the epidermal growth factor receptor (EGFR) gene mutation status in lung adenocarcinoma (ADC) patients.

METHODS

Data of the test cohort of 191 patients and the validation cohort of 55 patients with newly diagnosed ADC were retrospectively reviewed. All patients underwent F-FDG PET/CT scans and EGFR mutation tests prior to treatment. The metabolic parameters obtained from F-FDG PET/CT combining with clinical characteristics were analyzed by using univariate and multivariate logistic regression analyses. Then two cohorts were enrolled to validate the predictive model by area under the receiver-operating characteristic curve (AUC), respectively.

RESULTS

EGFR mutation-positive was seen of 33.0% (63/191) and 32.7% (18/55) in two cohorts, respectively. In univariate analysis, female, nonsmokers, metabolic parameters of primary tumor [mean standardized uptake value, metabolic tumor volume (pMTV), and total lesion glycolysis], non-necrosis of primary tumor, and serum tumor markers [carbohydrate antigen 19-9, squamous cell carcinoma antigen, and precursor of gastrin releasing peptide (proGRP)] were significantly relevant with EGFR mutation. In multivariate analysis with adjustment of age and TNM stage, pMTV (<8.13 cm), proGRP (≥38.44 pg/ml) and women were independent significant predictors for EGFR mutation. The AUC for the predictive value of these factors was 0.739 [95% confidence interval (CI) 0.665-0.813] in the cohort of 191 patients and 0.716 (95% CI 0.567-0.865) in the cohort of 55 patients, respectively.

CONCLUSION

Low pMTV (<8.13 cm) was an independent predictor and could be integrated with women and high proGRP (≥38.44 pg/ml) to enhance the discriminability on the EGFR mutation status in ADC patients.

Colorectal Cancer: From Genetic Landscape to Targeted Therapy

Colorectal cancer (CRC) is the third most common cancer type and the second cause of death worldwide. The advancement in understanding molecular pathways involved in CRC has led to new classifications based on the molecular characteristics of each tumor and also improved CRC management through the integration of targeted therapy into clinical practice. In this review, we will present the main molecular pathways involved in CRC carcinogenesis, the molecular classifications. The anti-VEGF and anti-EGFR therapies currently used in CRC treatment and those under clinical investigation will also be outlined, as well as the mechanisms of primary and acquired resistance to anti-EGFR monoclonal antibodies (cetuximab and panitumumab). Targeted therapy has led to great improvement in the treatment of metastatic CRC. However, there has been variability in CRC treatment outcomes due to molecular heterogeneity in colorectal tumors, which underscores the need for identifying prognostic and predictive biomarkers for CRC-targeted drugs.

Biomarkers of laryngeal squamous cell carcinoma: a review

Laryngeal carcinoma is the second common malignancy of the upper aerodigestive tract after lung cancer; in most cases is a squamous cell carcinoma, whose risk factors include tobacco smoking and alcohol consumption. Despite therapeutic progress, the five-year overall survival rate for this malignancy has remained nearly 50% and many patients already present metastasis at the time of diagnosis. To date, there are no tools that predict the evolution of laryngeal carcinoma: in this light, during the last years, many studies were planned with the aim to investigate the role played by different biomarkers expressed by larynx cancer, which can help make an early diagnosis, predict disease evolution and direct therapeutic choice. This review aims to summarize these markers and correlating them with disease evolution.

Therapeutically reprogrammed nutrient signalling enhances nanoparticulate albumin bound drug uptake and efficacy in KRAS-mutant cancer

Nanoparticulate albumin bound paclitaxel (nab-paclitaxel, nab-PTX) is among the most widely prescribed nanomedicines in clinical use, yet it remains unclear how nanoformulation affects nab-PTX behaviour in the tumour microenvironment. Here, we quantified the biodistribution of the albumin carrier and its chemotherapeutic payload in optically cleared tumours of genetically engineered mouse models, and compared the behaviour of nab-PTX with other clinically relevant nanoparticles. We found that nab-PTX uptake is profoundly and distinctly affected by cancer-cell autonomous RAS signalling, and RAS/RAF/MEK/ERK inhibition blocked its selective delivery and efficacy. In contrast, a targeted screen revealed that IGF1R kinase inhibitors enhance uptake and efficacy of nab-PTX by mimicking glucose deprivation and promoting macropinocytosis via AMPK, a nutrient sensor in cells. This study thus shows how nanoparticulate albumin bound drug efficacy can be therapeutically improved by reprogramming nutrient signalling and enhancing macropinocytosis in cancer cells.

Rational design-aided discovery of novel 1,2,4-oxadiazole derivatives as potential EGFR inhibitors

A molecular dynamics-based sampling of epidermal growth factor receptor tyrosine kinase (EGFR-TK) was carried out to search for energetically more stable protein, which was then used for molecular docking of a series of 1,2,4-oxadiazole derivatives previously reported from our laboratory. A total of 14 compounds were docked, where compounds 6a and 6b showed better binding to EGFR in silico. Further, physicochemical properties of all the compounds were calculated, which suggested that all the molecules obeyed Lipinski's rule of 5 and had favorable polar surface area and CaCO2 permeability along with the low potential for HERG inhibition. All the compounds were then screened for their ability to produce cytotoxicity in four different cell lines overexpressing EGFR (A549, HCT-116, HEPG2, MCF-7) and one EGFR negative cancer cell line (SW620); at three concentrations: 10, 1, and 0.1 µM. None of the compounds showed activity against SW620, which suggested that the compounds show cytotoxicity through inhibition of EGFR. Compounds that showed promise in this 3-concentration screen were further subjected to multiple dose-response curves to identify the IC₅₀ values for the shortlisted eight compounds. It was encouraging to see 6a and 6b showing the best IC₅₀ values against almost all the cell-lines which further suggests that our design protocol can be applied to optimize this lead (which are currently in the low micromolar range) to design the homologous compounds to achieve the desired potency in the nanomolar range and also to achieve selectivity across a range of kinases.

Anti‑HER3 monoclonal antibody exerts antitumor activity in a mouse model of colorectal adenocarcinoma

HER3 belongs to the epidermal growth factor receptor (EGFR) family and is known to form an active heterodimer with other three family members EGFR, HER2, and HER4. HER3 is overexpressed in lung, breast, colon, prostate, and gastric cancers. In the present study, we developed and validated an anti-HER3 monoclonal antibody (mAb), H₃Mab-17 (IgG_2a, kappa), by immunizing mice with HER3-overexpressed CHO-K1 cells (CHO/HER3). H₃Mab-17 was found to react specifically with endogenous HER3 in colorectal carcinoma cell lines, using flow cytometry. The K_D for H₃Mab-17 in CHO/HER3 and Caco-2 (a colon cancer cell line) were determined to be 3.0×10⁻⁹ M and 1.5×10⁻⁹ M via flow cytometry, respectively, suggesting high binding affinity of H₃Mab-17 to HER3. Then, we assessed the H₃Mab-17 antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) against Caco-2, and evaluated its antitumor capacity in a Caco-2 ×enograft model. In vitro experiments revealed H₃Mab-17 had strongly induced both ADCC and CDC against Caco-2 cells. In vivo experiments on Caco-2 ×enografts revealed that H₃Mab-17 treatment significantly reduced tumor growth compared with the control mouse IgG. These data indicated that H₃Mab-17 could be a promising treatment option for HER3-expressing colon cancers.

Inhibition of Ras and STAT3 activity of 4-(tert-butyl)-N-carbamoylbenzamide as antiproliferative agent in HER2-expressing breast cancer cells

OBJECTIVES

Human epidermal growth factor receptor type 2 (HER2)-expressing breast cancer patients indicate poor prognosis in disease progression. HER2 overexpression can increase activities of Ras-mitogen activated protein kinase (Ras-MAPK) pathway and Janus Kinase (JAK)-STAT3, increasing breast cancer cell proliferation as demonstrated by marker Ki67. Therapeutic options for HER2-expressing breast cancer are limited and have major side effects, so anticancer development as an antiproliferative is needed. From previous research, synthetic chemical 4-(tert-butyl)-N-carbamoylbenzamide (4TBCB) compound has cytotoxic activity in vitro on HER2-expressing breast cancer cells. This study wanted to determine the mechanism 4TBCB compound in inhibiting HER2 signaling through Rat Sarcoma (Ras) and signal transducer and activator of transcription 3 (STAT3) pathway in HER2-expressing breast cancer cells.

METHODS

Breast cancer cells were isolated from the biopsy tissue of breast cancer patients. The isolated cells were cultured and given 4TBCB test compound with three concentrations (0.305, 0.61, and 1.22 mM) and lapatinib 0.05 mM as a comparison compound. Cancer cell cultures were stained with monoclonal antibodies phosphorylated HER2 (pHER2), phosphorylated Ras (pRas), phosphorylated STAT3 (pSTAT3), and Ki67. The expression of pHER2, pRas, pSTAT3, and Ki67 proteins was observed using the immunofluorescence method and the results were compared with control cells, namely cancer cells that were not given 4TBCB and lapatinib but stained with monoclonal antibodies.

RESULTS

4TBCB compounds (0.61 and 1.22 mM) and lapatinib can reduce pHER2, pRas, pSTAT3, and Ki67 expressions compared to control cells.

CONCLUSIONS

4TBCB compounds (0.61 and 1.22 mM) can reduce pHER2, pRas, pSTAT3, Ki67 expressions and predicted to inhibit HER2 signaling through the Ras and STAT3 pathways in HER2-expressing breast cancer cells.

Potentiating Therapeutic Effects of Epidermal Growth Factor Receptor Inhibition in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is a subset of breast cancer with aggressive characteristics and few therapeutic options. The lack of an appropriate therapeutic target is a challenging issue in treating TNBC. Although a high level expression of epidermal growth factor receptor (EGFR) has been associated with a poor prognosis among patients with TNBC, targeted anti-EGFR therapies have demonstrated limited efficacy for TNBC treatment in both clinical and preclinical settings. However, with the advantage of a number of clinically approved EGFR inhibitors (EGFRis), combination strategies have been explored as a promising approach to overcome the intrinsic resistance of TNBC to EGFRis. In this review, we analyzed the literature on the combination of EGFRis with other molecularly targeted therapeutics or conventional chemotherapeutics to understand the current knowledge and to provide potential therapeutic options for TNBC treatment.

The Root Extract of Scutellaria baicalensis Induces Apoptosis in EGFR TKI-Resistant Human Lung Cancer Cells by Inactivation of STAT3

Resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) is a major obstacle in managing lung cancer. The root of Scutellaria baicalensis (SB) traditionally used for fever clearance and detoxification possesses various bioactivities including anticancer effects. The purpose of this study was to investigate whether SB exhibited anticancer activity in EGFR TKI-resistant lung cancer cells and to explore the underlying mechanism. We used four types of human lung cancer cell lines, including H1299 (EGFR wildtype; EGFR TKI-resistant), H1975 (acquired TKI-resistant), PC9/ER (acquired erlotinib-resistant), and PC9/GR (acquired gefitinib-resistant) cells. The ethanol extract of SB (ESB) decreased cell viability and suppressed colony formation in the four cell lines. ESB stimulated nuclear fragmentation and the cleavage of poly(ADP-ribose) polymerase (PARP) and caspase-3. Consistently, the proportion of sub-G1 phase cells and annexin V+ cells were significantly elevated by ESB, indicating that ESB induced apoptotic cell death in EGFR TKI-resistant cells. ESB dephosphorylated signal transducer and activator of transcription 3 (STAT3) and downregulated the target gene expression. The overexpression of constitutively active STAT3 reversed ESB-induced apoptosis, suggesting that ESB triggered apoptosis in EGFR TKI-resistant cells by inactivating STAT3. Taken together, we propose the potential use of SB as a novel therapeutic for lung cancer patients with EGFR TKI resistance.

EGFR Overexpression and Sequence Analysis of KRAS, BRAF, and EGFR Mutation Hot Spots in Canine Intestinal Adenocarcinoma

Epidermal growth factor receptor (EGFR) is overexpressed in many human colorectal cancers and anti-EGFR agents are employed as immunotherapies. However, KRAS, EGFR, and BRAF gene mutations can influence the activity of the anti-EGFR agents. We evaluated EGFR expression at protein and mRNA levels in canine intestinal adenocarcinomas using immunohistochemistry (IHC) and RNA in situ hybridization (RNA-ISH). We also investigated the mutation status of EGFR, KRAS, and BRAF to aid the development of anti-EGFR agents for canine intestinal adenocarcinoma. EGFR expression was highest in adenocarcinoma, followed by intramucosal neoplasia (adenoma and in situ carcinoma), and nonneoplastic canine intestinal tissue, at both protein (P = .000) and mRNA (P = .005) levels. The EGFR, KRAS, and BRAF genes showed wild-type sequences at the mutation hot spots in all 13 specimens. Thus, EGFR might serve as a promising diagnostic marker in canine intestinal adenocarcinoma, and further studies would be needed to develop EGFR-targeted anticancer therapies.

Upregulation of endogenous TRAIL-elicited apoptosis is essential for metformin-mediated antitumor activity against TNBC and NSCLC

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) shows promising antitumor activity in preclinical studies. However, the efficacy of recombinant TRAIL in clinical trials is compromised by its short serum half-life and low in vivo stability. Induction of endogenous TRAIL may overcome the limitations and become a new strategy for cancer treatment. Here, we discovered that metformin increased TRAIL expression and induced apoptosis in triple-negative breast cancer (TNBC) and non-small cell lung cancer (NSCLC) cells. Metformin did not alter the expression of TRAIL receptors (TRAIL-R1/DR4 and TRAIL-R2/DR5). Metformin-upregulated TRAIL was secreted into conditioned medium (CM) and found to be functional, since the CM promoted TNBC cells undergoing apoptosis, which was abrogated by a recombinant TRAIL-R2-Fc chimera. Moreover, blockade of TRAIL binding to DR4/DR5 or specific knockdown of TRAIL expression significantly attenuated metformin-induced apoptosis. Studies with a tumor xenograft model revealed that metformin not only significantly inhibited tumor growth but also elicited apoptosis and enhanced TRAIL expression in vivo. Collectively, we have demonstrated that upregulation of TRAIL and activation of death receptor signaling are pivotal for metformin-induced apoptosis in TNBC and NSCLC cells. Our studies identify a novel mechanism of action of metformin exhibiting potent antitumor activity via induction of endogenous TRAIL.

Recent insights in the PI3K/Akt pathway as a promising therapeutic target in combination with EGFR-targeting agents to treat head and neck squamous cell carcinoma

Resistance to therapies targeting the epidermal growth factor receptor (EGFR), such as cetuximab, remains a major roadblock in the search for effective therapeutic strategies in head and neck squamous cell carcinoma (HNSCC). Due to its close interaction with the EGFR pathway, redundant or compensatory activation of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway has been proposed as a major driver of resistance to EGFR inhibitors. Understanding the role of each of the main proteins involved in this pathway is utterly important to develop rational combination strategies able to circumvent resistance. Therefore, the current work reviewed the role of PI3K/Akt pathway proteins, including Ras, PI3K, tumor suppressor phosphatase and tensing homolog, Akt and mammalian target of rapamycin in resistance to anti-EGFR treatment in HNSCC. In addition, we summarize PI3K/Akt pathway inhibitors that are currently under (pre)clinical investigation with focus on overcoming resistance to EGFR inhibitors. In conclusion, genomic alterations in and/or overexpression of one or more of these proteins are common in both human papillomavirus (HPV)-positive and HPV-negative HNSCC tumors. Therefore, downstream effectors of the PI3K/Akt pathway serve as promising drug targets in the search for novel therapeutic strategies that are able to overcome resistance to anti-EGFR treatment. Co-targeting EGFR and the PI3K/Akt pathway can lead to synergistic drug interactions, possibly restoring sensitivity to EGFR inhibitors and hereby improving clinical efficacy. Better understanding of the predictive value of PI3K/Akt pathway alterations is needed to allow the identification of patient populations that might benefit most from these combination strategies.

Design, synthesis, and biological evaluation of new pyrimidine-5-carbonitrile derivatives bearing 1,3-thiazole moiety as novel anti-inflammatory EGFR inhibitors with cardiac safety profile

A new series of pyrimidine-5-carbonitrile derivatives 8a-p carrying the 1,3-thiazole moiety has been designed and synthesized as novel anti-inflammatory EGFR inhibitors with cardiac and gastric safety profiles. 8a-p have been assessed for their inhibitory activity against COX-1/COX-2 activity. Compounds 8h, 8n, and 8p were found to be potent and selective COX-2 inhibitors (IC₅₀ = 1.03-1.71 μM) relative to celecoxib (IC₅₀ = 0.88 μM). The most potent COX-2 inhibitors have been further investigated for their in-vivo anti-inflammatory effect. Compounds 8h, 8n, and 8p showed anti-inflammatory activity up to 90%, 94% and 86% of meloxicam after 4 h interval. 8h, 8n, and 8p showed higher gastric safety profiles than meloxicam. A substantial reduction in serum concentrations of PGE₂, TNF-α, IL-6, iNO and MDA and a significant induction of TAC was also observed. In vivo experiments on heart rate and blood pressure established the cardiovascular safety profile of 8h, 8n, and 8p. Anti-proliferative and wild-type EGFR inhibitory assays displayed similar results to selective COX-2 inhibition where compounds 8h, 8n, and 8p had a superior inhibition than other tested ones. Molecular docking study demonstrated that these compounds revealed similar orientation and binding interactions as selective COX-2 inhibitors with a higher liability to enter the side pocket selectively. Also, they interacted with EGFR tyrosine kinase main amino acids similar to erlotinib with a strong binding energy score.

Dealing with NSCLC EGFR mutation testing and treatment: A comprehensive review with an Italian real-world perspective

Since their discovery, relevant efforts have been made to optimize the detection approaches to EGFR mutations as well as the clinical management of EGFR-mutated NSCLC. The recent shift from single gene testing to novel comprehensive detection platforms along with the development of new generation tyrosine kinase inhibitors, targeting both common and uncommon EGFR-mutations, is leading to a progressive increase in the number of patients who may benefit from targeted approaches, with subsequent impact on their long-term survival and quality of life. However, a prompt and adequate implementation of the most recent diagnostic and treatment advances in the routine practice often remains critical to be specifically addressed. In this review we provide a complete and updated overview of the different detection platforms and therapeutic options currently available for the clinical management of advanced EGFR-positive NSCLC, summarizing scientific evidence and describing molecular testing as well as treatment practice in the real-word scenario.

The Efficacy of First-Generation EGFR-TKI Combined With Brain Radiotherapy as the First-Line Treatment for Lung Adenocarcinoma Patients With Brain Metastases and EGFR Sensitive Mutations: A Retrospective study

Background:

It was controversial that whether LUAD patients with brain metastases (BMs) and EGFR sensitive mutations should be conducted using brain radiotherapy when treated with first-generation EGFR-TKI. Herein, a retrospective study was designed to compare the efficacy of first-generation EGFR-TKI combined with brain radiotherapy and EGFR-TKI alone as first-line treatment for these LUAD patients.

Patients and Methods:

We retrospectively analyzed the status of patients with advanced LUAD carrying EGFR sensitive mutations who received first-generation EGFR-TKI treatment in our center. iPFS was the first time of intracranial progression or death from the diagnosis of BMs, PFS was the time of progression of any site or death from the diagnosis of BMs, and OS was the time of confirmed BMs to death or the last follow-up time. Differences in characteristics between groups were compared using the Chi-square test. The Kaplan-Meier method was used to calculate the iPFS, PFS, and OS. Univariate analysis, multivariate analysis, and subgroup analysis were conducted by Cox regression model.

Results:

There were 77 patients (77/134, 57.5%) in the TKI + RT group and 57 patients (57/134, 42.5%) in the TKI group. TKI + RT group had a significant higher intracranial ORR and DCR, and the combination therapy was independently significantly associated with a longer iPFS (18.9 vs. 10.5 months, P = 0.0009), systematic PFS (12.5 vs. 8.4 months, P = 0.0071) and OS (30.8 vs. 22.7 months, P = 0.0183). Females, non-smokers, and younger patients benefited more from the combination therapy. Subgroup analysis demonstrated that the combination therapy could improve the iPFS in patients with more than 3 BMs (P = 0.005); however, it couldn’t improve the OS for these patients.

Conclusion:

Our study confirmed the effect of the combination of EGFR-TKI and brain radiotherapy as first-line treatment for LUAD patients with BMs and EGFR sensitive mutations.

KRAS and BRAF mutations in Iranian colorectal cancer patients: A systematic review and meta-analysis

Background:

Mutations in the EGFR signaling pathway play an important role in the development of colorectal cancer (CRC). Mutations in these genes, like KRAS and BRAF, affect the treatment strategies and associated with poor prognosis and relative resistance to anti-EGFR therapies. Our aim was to conduct a systematic and meta-analysis on all studies that have been conducted on the prevalence of these gene mutations in Iranian CRC patients.

Methods:

Four science citation index databases (MEDLINE, EMBASE, Web of Science and Cochrane library) and local databases were searched up to March 2018 with related keywords. Two reviewers independently screened and extracted the data. Quality of all included studies was assessed using an adapted checklist from STROBE. A random-effect model was used to calculate the total prevalence of KRAS and BRAF mutations in CRC subjects by the event rate (ER). Meta-regression was utilized to explore heterogeneity causes.

Results:

In total, from 573 records, 23 eligible studies (2662 patients) were included for data extraction and analysis. In 18 of 23 included studies, the prevalence of KRAS mutations was 33.9% (95% CI=30.1-37.9) with I2=65.17 (p<0.001). The occurrence of KRAS mutations in codon 12 and 13 was 76.9% (95% CI = 70.4-82.3%) with I2=84.88 (p<0.001) and 23.5% (95% CI=17.9-30.3) with I2=85.85 (p<0.001), respectively. In 9 of 23 studies, the BRAF mutation rate was 3.2% (95% CI=0.003-13.6) with I2=88.61 (p<0.001).

Conclusion:

The prevalence of these mutations in CRC patients shows a significant difference in the different regions of Iran, which is probably due to environmental and racial factors.

Structural Basis for the Functional Changes by EGFR Exon 20 Insertion Mutations

Activating somatic mutations of the epidermal growth factor receptor (EGFR) are frequently implicated in non-small cell lung cancer (NSCLC). While L858R and exon 19 deletion mutations are most prevalent, exon 20 insertions are often observed in NSCLC. Here, we investigated the structural implications of two common EGFR exon 20 insertions in NSCLC, V769insASV and D770insNPG. The active and inactive conformations of wild-type, D770insNPG and V769insASV EGFRs were probed with molecular dynamics simulations to identify local and global alterations that the mutations exert on the EGFR kinase domain, highlighting mechanisms for increased enzymatic activity. In the active conformation, the mutations increase interactions that stabilize the αC helix that is essential for EGFR activity. Moreover, the key Lys745-Glu762 salt bridge was more conserved in the insertion mutations. The mutants also preserved the state of the structurally critical aspartate-phenylalanine-glycine (DFG)-motif and regulatory spine (R-spine), which were altered in wild-type EGFR. The insertions altered the structure near the ATP-binding pocket, e.g., the P-loop, which may be a factor for the clinically observed tyrosine kinase inhibitor (TKI) insensitivity by the insertion mutants. The inactive state simulations also showed that the insertions disrupt the Ala767-Arg776 interaction that is key for maintaining the "αC-out" inactive conformation, which could consequently fuel the transition from the inactive towards the active EGFR state.

MPP7 promotes the migration and invasion of breast cancer cells via EGFR/AKT signaling

Metastasis is a major cause of breast cancer death. MPP7 is a cell polarity controller highly linked to cell migration; however, the function of MPP7 in breast cancer remains unknown. In this study, we reported that MPP7 expression was upregulated in breast cancer tissues and high MPP7 expression predicted poor survival in patients with breast cancer. Ectopic expression of MPP7 markedly enhanced the migration and invasion in breast cancer cells. In contrast, depletion of MPP7 resulted in impaired cell mobility and metastasis. Moreover, we demonstrated that MPP7 exerted its promotional effect via modulation of EMT and activation of the EGFR/AKT cascade. Our study reveals an oncogenic role of MPP7 in breast cancer and suggests that MPP7 may serve as a potential target for exploring novel therapeutic strategies against breast cancer metastasis.

Generation of functional conjunctival epithelium, including goblet cells, from human iPSCs

The conjunctival epithelium, which covers the sclera (the white of the eye) and lines the inside of the eyelids, is essential for mucin secretion and the establishment of a healthy tear film. Here, we describe human conjunctival development in a self-formed ectodermal autonomous multi-zone (SEAM) of cells that were derived from human-induced pluripotent stem cells (hiPSCs) and mimic whole-eye development. Our data indicate that epidermal growth factor (EGF) drives the generation of cells with a conjunctival epithelial lineage. We also show that individual conjunctival cells can be sorted and reconstituted by cultivation into a functional conjunctival epithelium that includes mucin-producing goblet cells. Keratinocyte growth factor (KGF), moreover, is necessary for the maturation of hiPSC-derived conjunctival epithelium-particularly the goblet cells-indicating key complementary roles of EGF and KGF in directing the differentiation and maturation, respectively, of the human conjunctival epithelium.

Discovery of Dosimertinib, a Highly Potent, Selective, and Orally Efficacious Deuterated EGFR Targeting Clinical Candidate for the Treatment of Non-Small-Cell Lung Cancer

Osimertinib is a highly potent and selective third-generation epidermal growth factor receptor (EGFR) inhibitor, which provides excellent clinical benefits and is now a standard-of-care therapy for advanced EGFR mutation-positive non-small-cell lung cancer (NSCLC). However, AZ5104, a primary toxic metabolite of osimertinib, has caused unwanted toxicities. To address this unmet medical need, we initiated an iterative program focusing on structural optimizations of osimertinib and preclinical characterization, leading to the discovery of a highly potent, selective, and orally efficacious deuterated EGFR-targeting clinical candidate, dosimertinib. Preclinical studies revealed that dosimertinib demonstrated robust in vivo antitumor efficacy and favorable PK profiles, but with lower toxicity than osimertinib. These preclinical data support further clinical development of dosimertinib for the treatment of NSCLC. Dosimertinib has received official approval in China to initiate the phase I clinical trial (registration numbers: CXHL2000060 and CXHL2000061).

Lung cancer molecular mutations and abnormal glycosylation as biomarkers for early diagnosis

Lung cancer is the leading cause of mortality and morbidity in tumor-related deaths in the world. Early detection of tumors can greatly improve the survival rate of patients. However, the lack of reliable blood biomarkers remains a major challenge for early diagnosis. The blood proteins secreted by the lung bronchi and bronchial arteries may have characteristic glycosylation patterns associated with tumors, which are different from normal physiological and pathological conditions. In this review, we outline the oncogenic drivers, signaling pathways related to KRAS, gene and protein mutations, and oncogenic regulation of protein glycosylation. Based on to the TCGA transcriptomics and antibody-based proteomics data, we discussed oncogene and glycoproteins detected in the blood as tumor biomarkers. We hypothesize that glycoproteins whose glycosylation can be reversed by targeted drugs may serve as potential tumor biomarkers.

The role of E3 ubiquitin ligases in the development and progression of glioblastoma

Despite recent advances in our understanding of the disease, glioblastoma (GB) continues to have limited treatment options and carries a dismal prognosis for patients. Efforts to stratify this heterogeneous malignancy using molecular classifiers identified frequent alterations in targetable proteins belonging to several pathways including the receptor tyrosine kinase (RTK) and mitogen-activated protein kinase (MAPK) signalling pathways. However, these findings have failed to improve clinical outcomes for patients. In almost all cases, GB becomes refractory to standard-of-care therapy, and recent evidence suggests that disease recurrence may be associated with a subpopulation of cells known as glioma stem cells (GSCs). Therefore, there remains a significant unmet need for novel therapeutic strategies. E3 ubiquitin ligases are a family of >700 proteins that conjugate ubiquitin to target proteins, resulting in an array of cellular responses, including DNA repair, pro-survival signalling and protein degradation. Ubiquitin modifications on target proteins are diverse, ranging from mono-ubiquitination through to the formation of polyubiquitin chains and mixed chains. The specificity in substrate tagging and chain elongation is dictated by E3 ubiquitin ligases, which have essential regulatory roles in multiple aspects of brain cancer pathogenesis. In this review, we begin by briefly summarising the histological and molecular classification of GB. We comprehensively describe the roles of E3 ubiquitin ligases in RTK and MAPK, as well as other, commonly altered, oncogenic and tumour suppressive signalling pathways in GB. We also describe the role of E3 ligases in maintaining glioma stem cell populations and their function in promoting resistance to ionizing radiation (IR) and chemotherapy. Finally, we consider how our knowledge of E3 ligase biology may be used for future therapeutic interventions in GB, including the use of blood-brain barrier permeable proteolysis targeting chimeras (PROTACs).

Review on Epidermal Growth Factor Receptor (EGFR) Structure, Signaling Pathways, Interactions, and Recent Updates of EGFR Inhibitors

The epidermal growth factor receptor (EGFR) belongs to the ERBB family of tyrosine kinase receptors. EGFR signaling cascade is a key regulator in cell proliferation, differentiation, division, survival, and cancer development. In this review, the EGFR structure and its mutations, signaling pathway, ligand binding and EGFR dimerization, EGF/EGFR interaction, and the progress in the development of EGFR inhibitors have been explored.

Spatio-temporal regulation of gene expression defines subpopulations of epidermal stem cells

The search for epidermal stem cells has gained the momentum as they possess unique biological characteristics and a potential in regeneration therapies. Several transcription factors and miRNAs have been identified as epidermal stem cell markers. However, the separation of epidermal stem cells from their progeny remains challenging. The introduction of single-cell transcriptomics pointed to the high degree of heterogeneity in epidermal stem cells imbedded within subpopulations of keratinocytes. Pseudotime inference, RNA velocity, and cellular entropy further enhanced our knowledge of stem cells, allowing for the discovery of the epidermal stem cell plasticity. We explore the main findings that lead to the discovery of the plastic trait within the epidermal stem cells and the implications of cell plasticity in regenerative medicine.

Chondrocytes respond both anabolically and catabolically to impact loading generally considered non-injurious

We aimed to determine the longitudinal effects of low-energy (generally considered non-injurious) impact loading on (1) chondrocyte proliferation, (2) chondroprogenitor cell activity, and (3) EGFR signaling. In an in vitro study, we assessed 127 full-thickness, cylindrical osteochondral plugs of bovine cartilage undergoing either single, uniaxial unconfined impact loads with energy densities in the range of 1.5-3.2mJ/mm³ or no impact (controls). We quantified cell responses at two, 24, 48, and 72 h via immunohistochemical labeling of Ki67, Sox9, and pEGFR antibodies. We compared strain, stress, and impact energy density as predictors for mechanotransductive responses from cells, and fit significant correlations using linear regressions. Our study demonstrates that low-energy mechanical impacts (1.5-3.2mJ/mm³) generally stimulate time-dependent anabolic responses in the superficial zone of articular cartilage and catabolic responses in the middle and deep zones. We also found that impact energy density is the most consistent predictor of cell responses to low-energy impact loading. These spatial and temporal changes in chondrocyte behavior result directly from low-energy mechanical impacts, revealing a new level of mechanotransductive sensitivity in chondrocytes not previously appreciated.

EGFR targeting for cancer therapy: Pharmacology and immunoconjugates with drugs and nanoparticles

The epidermal growth factor receptor (EGFR) belongs to the tyrosine kinase receptors family and is present in the epithelial cell membrane. Its endogenous activation occurs through the binding of different endogenous ligands, including the epidermal growth factor (EGF), leading to signaling cascades able to maintain normal cellular functions. Although involved in the development and maintenance of tissues in normal conditions, when EGFR is overexpressed, it stimulates the growth and progression of tumors, resulting in angiogenesis, invasion and metastasis, through some main cascades such as Ras/Raf/MAPK, PIK-3/AKT, PLC-PKC and STAT. Besides, considering the limitations of conventional chemotherapy that result in high toxicity and low tumor specificity, EGFR is currently considered an important target. As a result, several monoclonal antibodies are currently approved for use in cancer treatment, such as cetuximab (CTX), panitumumab, nimotuzumab, necitumumab and others are in clinical trials. Aiming to combine the chemotherapeutic agent toxicity and specific targeting to EGFR overexpressing tumor tissues, two main strategies will be discussed in this review: antibody-drug conjugates (ADCs) and antibody-nanoparticle conjugates (ANCs). Briefly, ADCs consist of antibodies covalently linked through a spacer to the cytotoxic drug. Upon administration, binding to EGFR and endocytosis, ADCs suffer chemical and enzymatic reactions leading to the release and accumulation of the drug. Instead, ANCs consist of nanotechnology-based formulations, such as lipid, polymeric and inorganic nanoparticles able to protect the drug against inactivation, allowing controlled release and also passive accumulation in tumor tissues by the enhanced permeability and retention effect (EPR). Furthermore, ANCs undergo active targeting through EGFR receptor-mediated endocytosis, leading to the formation of lysosomes and drug release into the cytosol. Herein, we will present and discuss some important aspects regarding EGFR structure, its role on internal signaling pathways and downregulation aspects. Then, considering that EGFR is a potential therapeutic target for cancer therapy, the monoclonal antibodies able to target this receptor will be presented and discussed. Finally, ADCs and ANCs state of the art will be reviewed and recent studies and clinical progresses will be highlighted. To the best of our knowledge, this is the first review paper to address specifically the EGFR target and its application on ADCs and ANCs.

Inhibition of histone deacetylases, topoisomerases and epidermal growth factor receptor by metal-based anticancer agents: Design & synthetic strategies and their medicinal attributes

Metal-based inhibitors of histone deacetylases (HDAC), DNA topoisomerases (Topos) and Epidermal Growth Factor Receptor (EGFR) have demonstrated their cytotoxic potential against various cancer types such as breast, lung, uterus, colon, etc. Additionally, these have proven their role in resolving the resistance issues, enhancing the affinity, lipophilicity, stability, and biocompatibility and therefore, emerged as potential candidates for molecularly targeted therapeutics. This review focusses on nature and role of metals and organic ligands in tuning the anticancer activity in multiple modes of inhibition considering HDACs, Topos or EGFR as one of the primary targets. The conceptual design and synthetic approaches of platinum and non-platinum metal complexes comprising of chiefly ruthenium, rhodium, palladium, copper, iron, nickel, cobalt, zinc metals coordinated with organic scaffolds, along with their biological activity profiles, structure-activity relationships (SARs), docking studies, possible modes of action, and their scope and limitations are discussed in detail.

Distinct EGFR Mutation Pattern in Patients With Non-Small Cell Lung Cancer in Xuanwei Region of China: A Systematic Review and Meta-Analysis

Background

In the Xuanwei region of China, lung cancer incidence and mortality are among the highest in China, attributed to severe air pollution generated by combustion of smoky coal. No study has yet comprehensively evaluated the prevalence of epidermal growth factor receptor (EGFR) mutation characteristics in patients with non-small cell lung cancer (NSCLC) in Xuanwei. This meta-analysis was designed to analyze the EGFR mutation pattern in NSCLC patients in Xuanwei region of Yunnan Province in China.

Methods

Electronic databases were comprehensively searched and relevant literatures were retrieved. The odds ratio (OR) for EGFR mutations between Xuanwei region and non-Xuanwei region was calculated, and the absolute incidence of EGFR mutations in Xuanwei was pooled by mutation subtype.

Results

Seven studies involving 1,355 patients with NSCLC from Yunnan Province (442 in Xuanwei and 913 in other regions) were included. The EGFR mutation rate ranged between 30.19% and 55.56%. Higher uncommon EGFR mutations (OR: 5.69, 95%CI: 2.23–14.49, P<0.001) and lower common EGFR mutations (OR: 0.18, 95%CI: 0.07–0.45, P<0.001) were found in Xuanwei region, compared with non-Xuanwei region. Specifically, the uncommon EGFR mutation rate was 59.50% and common EGFR mutation rate was 40.50% in Xuanwei. The mutation incidence of exon 18 G719X (OR: 3.21, 95%CI: 1.48–6.97, P=0.003), exon 20 S768I (OR: 6.44; 95%CI: 2.66–15.60; P<0.001), and exon 18 G719X + 20 S768I (OR: 6.55; 95%CI: 1.92–22.33; P=0.003) in Xuanwei were significantly higher, while the frequency of 19 deletion (OR: 0.28, 95%CI: 0.11–0.77, P<0.001) and 21 L858R mutation (OR: 0.51, 95%CI: 0.31–0.84, P=0.007) were lower.

Conclusions

The results highlight the distinct EGFR mutation spectrum of NSCLC patients in Xuanwei region compared with other regions, with higher uncommon mutations but lower common mutations. The distinct Xuanwei featured genetic variations provide a unique model to further study carcinogenesis of lung cancer.

Beyond bevacizumab: a review of targeted agents in metastatic small bowel adenocarcinoma

Small bowel cancers are rare tumors with an incidence 50-100-fold less than colorectal cancer. These tumors carry a poor prognosis. Owing to its rarity, treatment of this disease, particularly in its advanced stages, has not been optimized and is derived mainly from treatment regimens for colorectal cancer. Based on recent studies bevacizumab, an antibody directed against vascular endothelial growth factor and used in the management of metastatic CRC, has been added to treatment guidelines for metastatic small bowel adenocarcinoma. We investigate in this review the evidence behind other targeted treatments that may be beneficial in the treatment of metastatic small bowel adenocarcinoma. These are agents against EGFR, VEGFR-2, HER2, and NTRK as well as immune checkpoint inhibitors. The last class of drugs appears to hold the greatest promise based on the preponderance of evidence supporting its use. However, overall data remains sparse. Results of studies currently underway will be valuable in shedding more light on the management of this aggressive cancer.

The Prognostic Impact of Epidermal Growth Factor Receptor (EGFR) in Patients with Acute Myeloid Leukaemia

Expression of Epidermal Growth Factor Receptor (EGFR), an important proto-oncogene, regulates cell differentiation, proliferation, cell migration and survival in most of the cancer types. EGFR expression has been reported in Acute Myeloid Leukaemia (AML), however, many other reports nullified EGFR expression in AML. These contradictory data prompted us to reevaluate the expression of EGFR in AML and carry out a comparative survival analysis between EGFR expressing and non-expressing AML patients (Children and Acute Promyelocytic Leukaemia patients excluded). Bone marrow and/or peripheral blood samples were collected from 60 adult patients with AML with written informed consent. PCR, Real-Time Taqman gene expression assays were used for the detection of genetic alterations. Statistical analysis was conducted using SPSS software (IBM SPSS 20). In our study, EGFR expression was detected in 21 out of 60, in 35% (95% C.I. 23.45-48.48) AML patients. Overall survival was significantly shorter in patients with EGFR (p = < 0.01), with an average survival of 18.57 months (95% C.I. 12.42-24.73 months) compared with 31.27 months (95% C.I. 28.19-34.33 months) in patients without EGFR. EGFR expression was significantly higher in female patients compared to male (p = 0.037).This study confirms the presence of EGFR in AML and indicates that EGFR expression confers poor prognosis in AML. However, the underlying cause of this adverse prognostic effect has not been identified. Further clinical studies are warranted to determine the exact mechanism through which EGFR activity might contribute to AML progression and identify the potential therapeutic target for the reversal of resistance to conventional chemotherapeutics.

Present and Future of Anti-Glioblastoma Therapies: A Deep Look into Molecular Dependencies/Features

Glioblastoma (GBM) is aggressive malignant tumor residing within the central nervous system. Although the standard treatment options, consisting of surgical resection followed by combined radiochemotherapy, have long been established for patients with GBM, the prognosis is still poor. Despite recent advances in diagnosis, surgical techniques, and therapeutic approaches, the increased patient survival after such interventions is still sub-optimal. The unique characteristics of GBM, including highly infiltrative nature, hard-to-access location (mainly due to the existence of the blood brain barrier), frequent and rapid recurrence, and multiple drug resistance mechanisms, pose challenges to the development of an effective treatment. To overcome current limitations on GBM therapy and devise ideal therapeutic strategies, efforts should focus on an improved molecular understanding of GBM pathogenesis. In this review, we summarize the molecular basis for the development and progression of GBM as well as some emerging therapeutic approaches.

Protein kinases as targets for developing anticancer agents from marine organisms

Protein kinases play a fundamental role in the intracellular transduction because of their ability to phosphorylate plethora of proteins. Over the past three decades, numerous protein kinase inhibitors have been identified and are being used clinically successfully. The biodiversity of marine organisms provides a rich source for the discovery and development of novel anticancer agents in the treatment of human malignancies and a lot of bioactive ingredients from marine organisms display anticancer effects by affecting the protein kinases-mediated pathways. In the present mini-review, anticancer compounds from marine source were reviewed and discussed in context of their targeted pathways associated with protein kinases and the progress of these compounds as anticancer agents in recent five years were emphasized. The molecular entities and their modes of actions were presented. We focused on protein kinases-mediated signaling pathways including PI3K/Akt/mTOR, p38 MAPK, and EGFR. The marine compounds targeting special pathways of protein kinases were highlighted. We have also discussed the existing challenges and prospects related to design and development of novel protein kinase inhibitors from marine sources.

Applicability of Styrene-Maleic Acid Copolymer for Two Microbial Rhodopsins, RxR and HsSRI

The membrane-embedded protein rhodopsin is widely produced in organisms as a photoreceptor showing a variety of light-dependent biological functions. To investigate its molecular features, rhodopsin is often extracted from cellular membrane lipids by a suitable detergent as "micelles." The extracted protein is purified by column chromatography and then is often reconstituted into "liposomes" by removal of the detergent. The styrene-maleic acid ("SMA") copolymer spontaneously forms nanostructures containing lipids without detergent. In this study, we applied SMA to characterize two microbial rhodopsins, a thermally stable rhodopsin, Rubrobacter xylanophilus rhodopsin (RxR), and an unstable one, Halobacterium salinarum sensory rhodopsin I (HsSRI), and evaluated their physicochemical properties in SMA lipid particles compared with rhodopsins in micelles and in liposomes. Those two rhodopsins were produced in Escherichia coli cells and were successfully extracted from the membrane by the addition of SMA (5 w/v %) without losing their visible color. Analysis by dynamic light scattering revealed that RxR in SMA lipid particles (RxR-SMA) formed a discoidal structure with a diameter of 54 nm, which was 10 times smaller than RxR in phosphatidylcholine liposomes. The small particle size of RxR-SMA allowed us to obtain scattering-less visible spectra with a high signal-to-noise ratio similar to RxR in detergent micelles composed of n-dodecyl-β-D-maltoside. High-speed atomic force microscopy revealed that a single particle contained an average of 4.1 trimers of RxR (12.3 monomers). In addition, RxR-SMA showed a fast cyclic photoreaction (k = 13 s^-1) comparable with RxR in phosphatidylcholine liposomes (17 s^-1) but not to RxR in detergent micelles composed of n-dodecyl-β-D-maltoside (0.59 s^-1). By taking advantage of SMA, we determined the dissociation constant (K_d) of chloride for HsSRI as 34 mM. From these results, we conclude that SMA is a useful molecule forming a membrane-mimicking assembly for microbial rhodopsins having the advantages of detergents and liposomes.

EGFR-upregulated LIFR promotes SUCLG2-dependent castration resistance and neuroendocrine differentiation of prostate cancer

Neuroendocrine (NE) differentiation is a well-recognized phenotypic change of prostate cancer after androgen deprivation therapy (ADT), and it ultimately develops into an aggressive subset of this disease. However, the contribution of signaling pathways that lead to metabolic disorders and NE differentiation of prostate cancer remains unclear. In this study, we identified that ADT induced upregulation of the succinate-CoA ligase GDP-forming beta subunit (SUCLG2), which regulates succinate metabolism and NE differentiation of prostate cancer. We demonstrated a connection that upregulation of epidermal growth factor receptor (EGFR)-leukemia inhibitory factor receptor (LIFR) signaling induced SUCLG2 expression in prostate cancer cells. The LIFR is upregulated by nuclear EGFR, which acts as a transcriptional regulator, directly binds to the LIFR promoter, and drives NE differentiation and glycolysis of prostate cancer. LIFR upregulation is associated with SUCLG2, which increased succinate synthesis and enzymatic activities of mitochondrial nucleoside diphosphate kinase (NDPK) in prostate cancer cells. Knockdown of SUCLG2 suppressed NE differentiation in cultured cells and reduced prostate tumor growth in a xenograft model. Analysis of prostate tissue samples showed increased intensity of nuclear EGFR associated with the LIFR and SUCLG2 in castration-resistant prostate cancer tumors. Our study provides a mechanism whereby ADT upregulates EGFR-LIFR signaling that activates SUCLG2, which subsequently stimulates the metabolic changes associated with NE differentiation and aggressive prostate cancer phenotype.

An Activatable Nano-Prodrug for Treating Tyrosine-Kinase-Inhibitor-Resistant Non-Small Cell Lung Cancer and for Optoacoustic and Fluorescent Imaging

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer and the cause of high rate of mortality. The epidermal growth factor receptor (EGFR)-targeted tyrosine kinase inhibitors are used to treat NSCLC, yet their curative effects are usually compromised by drug resistance. This study demonstrates a nanodrug for treating tyrosine-kinase-inhibitor-resistant NSCLC through inhibiting upstream and downstream EGFR signaling pathways. The main molecule of the nanodrug is synthesized by linking a tyrosine kinase inhibitor gefitinib and a near-infrared dye (NIR) on each side of a disulfide via carbonate bonds, and the nanodrug is then obtained through nanoparticle formation of the main molecule in aqueous medium and concomitant encapsulation of a serine threonine protein kinase (Akt) inhibitor celastrol. Upon administration, the nanodrug accumulates at the tumor region of NSCLC-bearing mice and releases the drugs for tumor inhibition, and the dye for fluorescence and optoacoustic imaging. Through suppressing the phosphorylation of upstream EGFR and downstream Akt in the EGFR pathway by gefitinib and celastrol, respectively, the nanodrug exhibits high inhibition efficacy against orthotopic NSCLC in mouse models.

Diastereoselective and regioselective synthesis of adenosine thionucleoside analogues using an acyclic approach

An acyclic approach to synthesize thiofuranoside N-glycosides bearing an adenine nucleobase is presented herein. This approach provides a significant improvement in terms of regio- and diastereoselectivity compared with the current paradigms used for their formation. Activation of acyclic dithioacetal substrates bearing either a C2′-alkoxy or fluoro group and coupling with purine nucleobases selectively generates 1′,2′-syn thioaminals. The regiochemistry of the nucleobase coupling (N7 or N9) can also be controlled by using either silylated or unsilylated purines. A subsequent SN2-like cyclization of these 1′,2′-syn acyclic thioaminals results in the desired 1′,2′-cis thionucleoside analogues.

Molecular Pathology of Primary Non-small Cell Lung Cancer

Lung carcinoma is one of the most common human cancers and is estimated to have an incidence of approximately 2 million new cases per year worldwide with a 20% mortality rate. Lung cancer represents one of the leading causes of cancer related death in the world. Of all cancer types to affect the pulmonary system, non-small cell lung carcinoma comprises approximately 80-85% of all tumors. In the past few decades cytogenetic and advanced molecular techniques have helped define the genomic landscape of lung cancer, and in the process, revolutionized the clinical management and treatment of patients with advanced non-small cell lung cancer. The discovery of specific, recurrent genetic abnormalities has led to the development of targeted therapies that have extended the life expectancy of patients who develop carcinoma of the lungs. Patients are now routinely treated with targeted therapies based on identifiable molecular alterations or other predictive biomarkers which has led to a revolution in the field of pulmonary pathology and oncology. Numerous different testing modalities, with various strengths and limitations now exist which complicate diagnostic algorithms, however recently emerging consensus guidelines and recommendations have begun to standardize the way to approach diagnostic testing of lung carcinoma. Herein we provide an overview of the molecular genetic landscape of non-small cell lung carcinoma, with attention to those clinically relevant alterations which drive management, as well as review current recommendations for molecular testing.

Melittin from Apis florea Venom as a Promising Therapeutic Agent for Skin Cancer Treatment

Melittin, a major component found in bee venom, is produced by the Apis species of the honey bee. In this study, the effect of melittin derived from Apis florea (Mel-AF), which is a wild honey bee species that is indigenous to Thailand, was investigated against human malignant melanoma (A375) cells. In this study, Mel-AF exhibited considerable potential in the anti-proliferative action of A375 cells. Subsequently, the cellular mechanism of Mel-AF that induced cell death was investigated in terms of apoptosis. As a result, gene and protein expression levels, which indicated the activation of cytochrome-c release and caspase-9 expression, eventually triggered the release of the caspase-3 executioner upon Mel-AF. We then determined that apoptosis-mediated cell death was carried out through the intrinsic mitochondrial pathway. Moreover, advanced abilities, including cell motility and invasion, were significantly suppressed. Mel-AF manipulated the actin arrangement via the trapping of stress fibers that were found underneath the membrane, which resulted in the defective actin cytoskeleton organization. Consequently, the expression of EGFR, a binding protein to F-actin, was also found to be suppressed. This outcome strongly supports the effects of Mel-AF in the inhibition of progressive malignant activity through the disruption of actin cytoskeleton-EGFR interaction and the EGFR signaling system. Thus, the findings of our current study indicate the potential usefulness of Mel-AF in cancer treatments as an apoptosis inducer and a potential actin-targeting agent.

Molecular characterization and function of EGFR during viral infectionprocess in Mandarin fishSiniperca chuatsi

Epidermal growth factor receptor (EGFR) is a tyrosine kinase protein and plays a critical role in virus infection by modulating innate immunity. In this study, we cloned and sequenced the EGFR coding sequence of mandarin fish, designed as scEGFR, and explored its characteristics. scEGFR mRNA was widely expressed in the tested tissues of mandarin fish, and the higher mRNA levels were expressed in kidney and spleen. scEGFR expression was up-regulated in spleen and CPB cells at early stage of ISKNV and SCRV infection. Gefitinib (EGFR inhibitor) inhibited ISKNV and SCRV replication, and increased the expression of the interferon-stimulated genes (ISG). However the EGF (EGFR activator) promoted ISKNV and SCRV replication, and decreased the interferon-stimulated genes. Those results indicated that scEGFR and its signaling involved in ISKNV and SCRV infection, and EGFR activation negatively regulated the interferon response, providing a potential target for the development of new therapic strategy against ISKNV and SCRV.

Drug mechanism-of-action discovery through the integration of pharmacological and CRISPR screens

Low success rates during drug development are due, in part, to the difficulty of defining drug mechanism-of-action and molecular markers of therapeutic activity. Here, we integrated 199,219 drug sensitivity measurements for 397 unique anti-cancer drugs with genome-wide CRISPR loss-of-function screens in 484 cell lines to systematically investigate cellular drug mechanism-of-action. We observed an enrichment for positive associations between the profile of drug sensitivity and knockout of a drug's nominal target, and by leveraging protein-protein networks, we identified pathways underpinning drug sensitivity. This revealed an unappreciated positive association between mitochondrial E3 ubiquitin-protein ligase MARCH5 dependency and sensitivity to MCL1 inhibitors in breast cancer cell lines. We also estimated drug on-target and off-target activity, informing on specificity, potency and toxicity. Linking drug and gene dependency together with genomic data sets uncovered contexts in which molecular networks when perturbed mediate cancer cell loss-of-fitness and thereby provide independent and orthogonal evidence of biomarkers for drug development. This study illustrates how integrating cell line drug sensitivity with CRISPR loss-of-function screens can elucidate mechanism-of-action to advance drug development.

EGFR: An essential receptor tyrosine kinase-regulator of cancer stem cells

The Epidermal Growth Factor Receptor (EGFR) is frequently expressed at elevated levels in different forms of cancer and expression often correlates positively with cancer progression and poor prognosis. Different mutant forms of this protein also contribute to cancer heterogeneity. A constitutively active form of EGFR, EGFRvIII is one of the most important variants. EGFR is responsible for the maintenance and functions of cancer stem cells (CSCs), including stemness, metabolism, immunomodulatory-activity, dormancy and therapy-resistance. EGFR regulates these pathways through several signaling cascades, and often cooperates with other RTKs to exert further control. Inhibitors of EGFR have been extensively studied and display some anticancer efficacy. However, CSCs can also acquire resistance to EGFR inhibitors making effective therapy even more difficult. To ameliorate this limitation of EGFR inhibitors when used as single agents, it may be of value to simultaneously combine multiple EGFR inhibitors or use EGFR inhibitors with regulators of other important cancer phenotype regulating molecules, such as STAT3, or involved in important processes such as DNA repair. These combinatorial approaches require further experimental confirmation, but if successful would expand and improve therapeutic outcomes employing EGFR inhibitors as one arm of the therapy.

Molecular-Biology-Driven Treatment for Metastatic Colorectal Cancer

BACKGROUND

Metastatic CRC (mCRC) is a molecular heterogeneous disease. The aim of this review is to give an overview of molecular-driven treatment of mCRC patients.

METHODS

A review of clinical trials, retrospective studies and case reports was performed regarding molecular biomarkers with therapeutic implications.

RESULTS

RAS wild-type status was confirmed as being crucial for anti-epidermal growth factor receptor (EGFR) monoclonal antibodies and for rechallenge strategy. Antiangiogenic therapies improve survival in first- and second-line settings, irrespective of RAS status, while tyrosine kinase inhibitors (TKIs) remain promising in refractory mCRC. Promising results emerged from anti-HER2 drugs trials in HER2-positive mCRC. Target inhibitors were successful for BRAFV600E mutant mCRC patients, while immunotherapy was successful for microsatellite instability-high/defective mismatch repair (MSI-H/dMMR) or DNA polymerase epsilon catalytic subunit (POLE-1) mutant patients. Data are still lacking on NTRK, RET, MGMT, and TGF-β, which require further research.

CONCLUSION

Several molecular biomarkers have been identified for the tailored treatment of mCRC patients and multiple efforts are currently ongoing to increase the therapeutic options. In the era of precision medicine, molecular-biology-driven treatment is the key to impro patient selection and patient outcomes. Further research and large phase III trials are required to ameliorate the therapeutic management of these patients.

Impact of Genomic Mutation and Timing of Y90 Radioembolization in Colorectal Liver Metastases

PURPOSE

To investigate timing of Yttrium-90 radioembolization (Y90) during treatment course, genomics, and other clinical factors as predictors of overall survival (OS) in colorectal liver metastasis (CRLM) that have progressed on at least one line of chemotherapy.

MATERIALS AND METHODS

This was a retrospective study from 2013 to 2018 of patients with CRLM and genomic analysis prior to Y90 at a multihospital tertiary referral center. OS from liver metastasis diagnosis and predictors of OS were analyzed using Kaplan-Meier estimation with log-rank and Cox regression analyses.

RESULTS

Overall, 58 patients with CRLM who progressed on at least one line of chemotherapy who had genomic analysis prior to Y90 were identified. Median OS after hepatic metastasis was 29.9 months. Of these, 16 (28%) patients received Y90 after failure of the first-line systemic chemotherapy. There was significantly prolonged OS in patients receiving Y90 immediately following failure of the first-line chemotherapy folinic acid, fluorouracil, oxaliplatin ((FOLFOX) ± bevacizumab) versus following multiple lines of chemotherapy (median OS of 46.3 vs. 26.6 months, P = 0.005). The presence of genetic mutation in tumor, MAPK pathway wild type, left-sided primary tumor, low MELD score, and non-diffuse unilobar disease were also found to be predictors prolonged survival on log-rank analysis (P's < 0.05). On multivariate analysis, receiving Y90 after failure of the first line of chemotherapy, low baseline MELD score, and baseline ECOG performance score of 0 were all found to be independent predictors of prolonged OS from the time of metastatic disease diagnosis (P's < 0.05).

CONCLUSION

In patients with CRLM, receiving Y90 after failing the first line of chemotherapy, lack of genetic mutation, low MELD score, and lower tumor burden appear to be independent predictors of prolonged OS.

LEVEL OF EVIDENCE

Level 4, case-control study.