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Modular nanotransporters (MNTs) are drug delivery systems for targeted cancer treatment. As MNTs are composed of several modules, they offer the advantage of high specificity and biocompatibility in delivering drugs to the target compartment of cancer cells. The large carrier module brings together functioning MNT modules and serves as a platform for drug attachment. The development of smaller-sized MNTs via truncation of the carrier module appears advantageous in facilitating tissue penetration. In this study, two new MNTs with a truncated carrier module containing either an N-terminal (MNTN) or a C-terminal (MNTC) part were developed by genetic engineering. Both new MNTs demonstrated a high affinity for target receptors, as revealed by fluorescent-labeled ligand-competitive binding. The liposome leakage assay proved the endosomolytic activity of MNTs. Binding to the importin heterodimer of each truncated MNT was revealed by a thermophoresis assay, while only MNTN possessed binding to Keap1. Finally, the photodynamic efficacy of the photosensitizer attached to MNTN was significantly higher than when attached to either MNTC or the original MNTs. Thus, this work reveals that MNT’s carrier module can be truncated without losing MNT functionality, favoring the N-terminal part of the carrier module due to its ability to bind Keap1.

IntroductionColorectal cancer and other adult solid cancers pose a significant challenge for successful treatment because the tumor microenvironment both hinders the action of conventional therapeutics and suppresses the immune activities of infiltrating leukocytes. The immune suppression is largely the effect of enhanced local mediators such as purine nucleosides and eicosanoids. Genetic approaches have the promise of interfering with these mechanisms of local immunosuppression to allow both intrinsic and therapeutic immunological anticancer processes. Bacterial phages offer a novel means of enabling access into tissues for therapeutic genetic manipulations.MethodsWe generated spheroids of fibroblastic and CRC cancer cells to model the 3-dimensional stromal and parenchymal components of colorectal tumours. We used these to examine the access and effects of both wildtype (WT) and epidermal growth factor (EGF)-presenting bacteriophage λ (WT- λ and EGF-λ) as a means of delivery of targeted genetic interventions in solid cancers. We used both confocal microscopy of spheroids exposed to AF488-tagged phages, and the recovery of viable phages as measured by plaque-forming assays to evaluate access; and measures of mitochondrial enzyme activity and cellular ATP to evaluate the outcome on the constituent cells.ResultsUsing flourescence-tagged derivatives of these bacteriophages (AF488-WT-λ and AF488-EGF-λ) we showed that phage entry into these tumour microenvironments was possible and that the EGF ligand enabled efficient and persistent uptake into the cancer cell mass. EGF-λ became localized in the intracellular portion of cancer cells and was subjected to subsequent cellular processing. The targeted λ phage had no independent effect upon mature tumour spheroids, but interfered with the early formation and growth of cancer tissues without the need for addition of a toxic payload, suggesting that it might have beneficial effects by itself in addition to any genetic intervention delivered to the tumour. Interference with spheroid formation persisted over the duration of culture.DiscussionWe conclude that targeted phage technology is a feasible strategy to facilitate delivery into colorectal cancer tumour tissue (and by extension other solid carcinomas) and provides an appropriate delivery vehicle for a gene therapeutic that can reduce local immunosuppression and/or deliver an additional direct anticancer activity.

Buyankhishig Dorjsuren,1,* Birendra Chaurasiya,2,* Zixuan Ye,1 Yanyan Liu,1 Wei Li,3 Chaoyang Wang,1 Di Shi,4 Colin E Evans,2 Thomas J Webster,4 Yan Shen1 1Department of Pharmaceutics, China Pharmaceutical University, Nanjing 210009, People’s Republic of China; 2Department of Pediatrics, Critical Care Division, Stanley Manne Children’s Research Institute, Ann & Robert H. Lurie Children’s Hospital of Chicago, Northwestern University Feinberg School of Medicine, Chicago, IL, USA; 3Department of Cardiology, Affiliated Hospital of Yangzhou University, Yangzhou 225002, People’s Republic of China; 4Department of Chemical Engineering, Northeastern University, Boston, MA, USA*These authors contributed equally to this workCorrespondence: Yan Shen; Thomas J Webster Tel +86 (025) 83271305; Tel +86 (025) 83271305; Email shenyan@cpu.edu.cn; th.webster@northeastern.eduBackground: One major limitation of cancer chemotherapy is a failure to specifically target a tumor, potentially leading to side effects such as systemic cytotoxicity. In this case, we have generated a cancer cell-targeting nanoparticle-liposome drug delivery system that can be activated by near-infrared laser light to enable local photo-thermal therapy and the release of chemotherapeutic agents, which could achieve combined therapeutic efficiency.Methods: To exploit the magnetic potential of iron oxide, we prepared and characterized citric acid-coated iron oxide magnetic nanoparticles (CMNPs) and encapsulated them into thermo-sensitive liposomes (TSLs). The chemotherapeutic drug, doxorubicin (DOX), was then loaded into the CMNP-TSLs, which were coated with an antibody against the epidermal growth factor receptor (EGFR), cetuximab (CET), to target EGFR-expressing breast cancer cells in vitro and in vivo studies in mouse model.Results: The resulting CET-DOX-CMNP–TSLs were stable with an average diameter of approximately 120 nm. First, the uptake of TSLs into breast cancer cells increased by the addition of the CET coating. Next, the viability of breast cancer cells treated with CET-CMNP-TSLs and CET-DOX-CMNP-TSLs was reduced by the addition of photo-thermal therapy using near-infrared (NIR) laser irradiation. What is more, the viability of breast cancer cells treated with CMNP-TSLs plus NIR was reduced by the addition of DOX to the CMNP-TSLs. Finally, photo-thermal therapy studies on tumor-bearing mice subjected to NIR laser irradiation showed that treatment with CMNP-TSLs or CET-CMNP-TSLs led to an increase in tumor surface temperature to 44.7°C and 48.7°C, respectively, compared with saline-treated mice body temperature ie, 35.2°C. Further, the hemolysis study shows that these nanocarriers are safe for systemic delivery.Conclusion: Our studies revealed that a combined therapy of photo-thermal therapy and targeted chemotherapy in thermo-sensitive nano-carriers represents a promising therapeutic strategy against breast cancer.Keywords: breast cancer, cetuximab, doxorubicin, iron oxide magnetic nanoparticles, epidermal growth factor receptors, combined therapy

Abstract Osimertinib is a third‐generation, irreversible, oral epidermal growth factor receptor (EGFR)‐tyrosine kinase inhibitor (TKI) that potently and selectively inhibits both EGFR‐TKI sensitizing and EGFR T790M and has demonstrated efficacy in non‐small cell lung cancer (NSCLC) central nervous system metastases. In this phase I study, we assessed the effects of normal renal function (NRF) and severe renal impairment (SRI) on the pharmacokinetics (PK) of osimertinib in patients with solid tumors. Part A: patients with NRF (creatinine clearance [CrCL] ≥90 mL/min), and SRI, (CrCL

Abstract Breast cancer stem cells (BCSCs) are responsible for resistance to chemotherapy, high degree of metastasis, and poor prognosis, especially in triple‐negative breast cancer (TNBC). The CD24lowCD44high and high aldehyde dehydrogenase 1 (ALDH1) cell subpopulation (CD24lowCD44high ALDH1+) exhibit very high tumor initiating capacity. In the current study, the upregulated genes are analyzed in both CD24lowCD44high and ALDH1+ cell populations at single‐cell resolution, and a highly expressed membrane protein, SGCE, is identified in both BCSC populations. Further results show that SGCE depletion reduces BCSC self‐renewal, chemoresistance, and metastasis both in vitro and in vivo, partially through affecting the accumulation of extracellular matrix (ECM). For the underlying mechanism, SGCE functions as a sponge molecule for the interaction between epidermal growth factor receptor (EGFR) and its E3 ubiquitination ligase (c‐Cbl), and thus inhibits EGFR lysosomal degradation to stabilize the EGFR protein. SGCE knockdown promotes sensitivity to EGFR tyrosine kinase inhibitors (TKIs), providing new clues for deciphering the current failure of targeting EGFR in clinical trials and highlighting a novel candidate for BCSC stemness regulation.

Multiple seborrheic keratosis (SK), especially when there is overexpression of the epidermal growth factor receptor (EGFR), is considered paraneoplastic dermatosis, but it is almost always associated with multiple fibroepithelial polyps (PF) and pseudoacanthosis, skin diseases in which the leading role is played by insulin resistance and type 2 diabetes mellitus. The study examines the possibility of the effect of disorders of carbohydrate metabolism on the clinical picture of multiple SK and the expression of EGFR.Aims. To study the clinical features of multiple SC and the expression of EGFR in patients, depending on the presence of concomitant type 2 diabetes mellitus.Materials and methods. There were 65 patients with multiple SK at the age from 55 to 77 years, including women (44) and men (21). All the patients were examined skin, consultation of the endocrinologist. For a histological and immunohis-tochemical study (IHC), a single SK was surgically excised in each patient. IHC-reactions were carried out with monoclonal antibodies to EGFR. The result was assessed by the number of stained cytoplasmic membranes of tumor cells.Results. In 81.5 % of cases, multiple SK was associated in patients with type 2 diabetes mellitus. The location of the SK was also characteristic mainly in large folds of the skin, in contrast to patients without disorders of carbohydrate metabolism, in which the SK were located mainly on the lateral surfaces of the trunk and abdomen, without affecting the large folds of the skin. Multiple PF were also characteristic of individuals with type 2 diabetes mellitus. In IHC studies EGFR expression was detected in 100 % of cases in individuals with multiple SC and type 2 diabetes mellitus in over 30 % of tumor cells, and only in 16.7 % of cases in individuals with multiple SK without violations of carbohydrate metabolism.Conclusions. The presence of multiple SK in patients, in combination with multiple PFs with characteristic tumor localization in large folds of the skin, serves as a diagnostic marker of carbohydrate metabolism disorders or predispositions to the development of type 2 diabetes. Increased expression of EGFR plays a leading role in the pathogenesis of multiple SK, stimulating the proliferation and growth of SK, in turn, as a consequence of impairment of insulin signaling pathways and insulin resistance.

Since cell nucleus is one of the most vulnerable compartments, the maximum therapeutic effect from a variety of locally acting agents, such as photosensitizers, alfa-emitters, Auger electron emitters, will be expected when they get there. Therefore, the targeted delivery of these agents into the nuclei of target tumor cells is necessary for their anticancer effects and minimization of side effects. Modular nanotransporters (MNT) are artificial polypeptides comprising several predefined modules that recognize target cell, launching their subsequent internalization, escape from endosomes, and transport the drug load to the nucleus. This technology significantly enhances the cytotoxicity of locally acting drugs in vitro and in vivo. Epidermal growth factor receptors (EGFR) are useful molecular targets as they are overexpressed in glioblastoma, head-and-neck cancer, bladder cancer, and other malignancies. Here, we examined the possibility of using internalizable anti-EGFR affibody as an EGFR-targeting MNT module for drug transport into the cancer cell nuclei. It binds to both murine and human EGFR facilitating preclinical studies. We showed that MNT with affibody on the N-terminus (MNTN-affibody) effectively delivered the Auger electron emitter 111In to target cell nuclei and had pronounced cytotoxic efficacy against EGFR-overexpressing human A431 epidermoid carcinoma cells. Using EGFR-expressing human adenocarcinoma MCF-7 cells, we demonstrated that in contrast to MNT with N-terminal epidermal growth factor (EGF), MNTN-affibody and MNT with EGF on the C-terminus did not stimulate cancer cell proliferation.

The basic contemporary data and the results of authors’ long-term personal research devoted to the role of auto / paracrine growth factors, their receptors and some down-stream signaling proteins (PI3K, Akt, NF-κB) in clinical course, prognosis and development of hormonal and drug sensitivity of various human tumors are reviewed. The data on the key targeted drugs suppressing various growth factor signaling pathways components are summarized with special attention to the criteria of assessment of individual sensitivity to these drugs including those based on modern molecular biologic technologies.

Background: Diabetes mellitus (DM) is a highly prevalent disease. Atrophy and spontaneous ulcers are the most common cutaneous manifestation of diabetic dermopathy (DD). Before spontaneous ulcers, we believe there is an underlying damage stage although the mechanism is unknown. Aims: To explore the expression of extracellular signal-regulated kinase1/2 (ERK1/2), its correlated upstream protein epidermal growth factor receptor (EGFR) and its downstream transcription factor E twenty-six (ETS)-like 1(ELK-1)in the damage of the diabetic rat skin, and to explore the role of ERK1/2 on the recessive damage to diabetic rat skin. Materials and Methods: Eighty Sprague-Dawley (SD) rats weighing 260-300 g were randomly divided into control and streptozotocin (STZ)-induced diabetes groups. After 0.5, 2, 4, and 8 weeks, the shaved skin specimens from the back of rats in both groups were collected to observe the histological characteristics of the skin, to measure the thickness of the epidermis and the dermis, and to observe the ultrastructure. Immunohistochemistry (IHC) and Western blot techniques were used to detect the expression and activation of ERK1/2, EGFR, ELK-1 in the skin of the rats. Results: There are ultrastructural changes in the DM skin. With the continuance of the diabetes course, the thicknesses of the epidermis and dermis decreased, and the expression of phospho-ERK1/2 (P-ERK1/2), EGFR, and ELK-1 was decreased gradually in the back skin of the diabetes rats. It was significantly lower in 4 and 8 week DM than that of the normal control ( P < 0.05). The expression of P-EGFR and P-ERK1/2 in the back skin of the diabetes rats was positively correlated ( r = 0.572 P < 0.05), and the positive correlation was also obtained between P-ERK1/2 and P-ELK-1 ( r = 0.715, P < 0.05). Conclusion: The phenomenon of recessive damage exists in the skin of diabetes rats, which probably may relate to the weakness of the signal transduction: P-EGFR → ERK1/2 → ELK-1.

Lipid rafts are small plasma membrane domains that contain high levels of cholesterol and sphingolipids. Traditional methods for the biochemical isolation of lipid rafts involve the extraction of cells with nonionic detergents followed by the separation of a low-density, detergent-resistant membrane fraction on density gradients. Because of concerns regarding the possible introduction of artifacts through the use of detergents, it is important to develop procedures for the isolation of lipid rafts that do not involve detergent extraction.We report here a simplified method for the purification of detergent-free lipid rafts that requires only one short density gradient centrifugation, but yields a membrane fraction that is highly enriched in cholesterol and protein markers of lipid rafts, with no contamination from nonraft plasma membrane or intracellular membranes.