scholarly journals Dual pH- and GSH-Responsive Degradable PEGylated Graphene Quantum Dot-Based Nanoparticles for Enhanced HER2-Positive Breast Cancer Therapy

Nanomaterials ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 91 ◽  
Author(s):  
Na Re Ko ◽  
Se Young Van ◽  
Sung Hwa Hong ◽  
Seog-Young Kim ◽  
Miran Kim ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Laser Scanning ◽  
Animal Studies ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Her2 Positive ◽  
Her2 Positive Breast Cancer ◽  
Positive Breast Cancer

Dual stimuli-responsive degradable carbon-based nanoparticles (DS-CNPs) conjugated with Herceptin (HER) and polyethylene glycol (PEG) have been designed for the treatment of HER2-positive breast cancer. Each component has been linked through disulfide linkages that are sensitive to glutathione in a cancer microenvironment. β-cyclodextrin (β-CD) on the surface of DS-CNPs formed an inclusion complex (DL-CNPs) with doxorubicin (DOX) at a high loading capacity of 5.3 ± 0.4%. In response to a high level of glutathione (GSH) and low pH in a tumor environment, DL-CNPs were rapidly degraded and released DOX in a controlled manner via disruption of host–guest inclusion. These novel DL-CNPs exhibited high cellular uptake with low toxicity, which induced the efficient inhibition of antitumor activity both in vitro and in vivo. Cell viability, confocal laser scanning microscopy, and animal studies indicate that DL-CNPs are a great platform with a synergistically enhanced antitumor effect from the dual delivery of HER and DOX in DL-CNPs.

scholarly journals A Novel Small Molecular Antibody, HER2-Nanobody, Inhibits Tumor Proliferation in HER2-Positive Breast Cancer Cells In Vitro and In Vivo

2021 ◽  
Vol 11 ◽  
Author(s):  
Yan Yan ◽  
Xiao Cheng ◽  
Lin Li ◽  
Rumeng Zhang ◽  
Yong Zhu ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Suppressive Effect ◽  
Her2 Positive ◽  
Her2 Positive Breast Cancer ◽  
Large Molecular Weight ◽  
Positive Breast Cancer

Breast cancer is the most common malignant cancer in women worldwide, especially in developing countries. Herceptin is a monoclonal antibody with an antitumor effect in HER2-positive breast cancer. However, the large molecular weight of Herceptin limited its employment. In this study, we constructed and screened HER2-nanobody and verified its tumor-suppressive effect in HER2-positive breast cancer cells. HER2-nanobody was established, filtrated, purified, and was demonstrated to inhibit cell total number, viability, colony formation and mitosis, and promote cell apoptosis in HER2-positive breast cancer cells in vitro. Treated with HER2-nanobody, tumor growth was significantly inhibited by both intratumor injection and tail intravenous injection in vivo. The phosphorylation of ERK and AKT was restrained by HER2-nanobody in HER2-positive breast cancer cells. RAS-RAF-MAPK and PI3K-AKT-mTOR are two important pathways involved in HER2. It was credible for HER2-nanobody to play the tumor suppressive role by inhibiting the phosphorylation of ERK and AKT. Therefore, HER2-nanobody could be employed as a small molecular antibody to suppress HER2-positive breast cancer.

scholarly journals Dual anti-HER2 blockade in late-line treatment of metastatic HER2-positive breast cancer

2021 ◽  
pp. 156-159
Author(s):  
M. A. Frolova ◽  
M. B. Stenina
Keyword(s):  
Breast Cancer ◽  
Treatment Options ◽  
Migration And Invasion ◽  
Line Treatment ◽  
Her2 Positive ◽  
Her2 Positive Breast Cancer ◽  
Wide Range ◽  
Positive Breast Cancer

In recent years, there has been a wide range of treatment options for patients with metastatic HER2-positive breast cancer, resulting in  the  highest life expectancy for  these patients among all subtypes. The  addition of  pertuzumab to trastuzumab and docetaxel has been shown to increase overall survival and is therefore recognized as the standard first-line treatment. The most optimal second-line treatment option is trastuzumab emtansine. In  addition, various combinations of  cytostatics and anti HER2 targeting agents can be used. The choice of treatment options in heavily pretreated patients is of great interest. If they have not previously received pertuzumab, is it worth to use it and which combination is the best? One possible option is the combination of eribulin with the dual anti-HER2 blockade with trastuzumab and pertuzumab. Eribulin is an anti-microtubule agent that irreversibly blocks mitosis. In addition, it has non-mitotic effects – in vivo and in vitro experiments demonstrated its ability to restore normal tumor vascularization, reduce the area of hypoxia and, as a consequence, decrease tumor cells migration and invasion. This article represents a clinical case of the use of eribulin with double anti-HER2 blockade in the 6th line of treatment in a patient with metastatic HER2-positive breast cancer. Long-term control of the disease (within 2 years) with a satisfactory quality of life has been demonstrated. 

scholarly journals Therapeutic targeting of HER2–CB2R heteromers in HER2-positive breast cancer

2019 ◽  
Vol 116 (9) ◽  
pp. 3863-3872 ◽  
Author(s):  
Sandra Blasco-Benito ◽  
Estefanía Moreno ◽  
Marta Seijo-Vila ◽  
Isabel Tundidor ◽  
Clara Andradas ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cannabinoid Receptor ◽  
Acquired Resistance ◽  
Diagnostic Tools ◽  
Breast Cancer Patients ◽  
Her2 Positive ◽  
Her2 Positive Breast Cancer ◽  
Positive Breast Cancer

Although human epidermal growth factor receptor 2 (HER2)-targeted therapies have dramatically improved the clinical outcome of HER2-positive breast cancer patients, innate and acquired resistance remains an important clinical challenge. New therapeutic approaches and diagnostic tools for identification, stratification, and treatment of patients at higher risk of resistance and recurrence are therefore warranted. Here, we unveil a mechanism controlling the oncogenic activity of HER2: heteromerization with the cannabinoid receptor CB2R. We show that HER2 physically interacts with CB2R in breast cancer cells, and that the expression of these heteromers correlates with poor patient prognosis. The cannabinoid Δ9-tetrahydrocannabinol (THC) disrupts HER2–CB2R complexes by selectively binding to CB2R, which leads to (i) the inactivation of HER2 through disruption of HER2–HER2 homodimers, and (ii) the subsequent degradation of HER2 by the proteasome via the E3 ligase c-CBL. This in turn triggers antitumor responses in vitro and in vivo. Selective targeting of CB2R transmembrane region 5 mimicked THC effects. Together, these findings define HER2–CB2R heteromers as new potential targets for antitumor therapies and biomarkers with prognostic value in HER2-positive breast cancer.

scholarly journals JAC1 suppresses proliferation of breast cancer through the JWA/p38/SMURF1/HER2 signaling

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Yanlin Ren ◽  
Dongyin Chen ◽  
Zurong Zhai ◽  
Junjie Chen ◽  
Aiping Li ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Ubiquitin Ligase ◽  
Breast Cancer Cells ◽  
E3 Ubiquitin Ligase ◽  
Her2 Positive ◽  
Her2 Positive Breast Cancer ◽  
Positive Breast Cancer

AbstractThe overexpression of HER2 is associated with a malignant proliferation of breast cancer. In this study, we developed a non-cytotoxic JWA gene activating compound 1 (JAC1) to inhibit the proliferation of HER2-positive breast cancer cells in vitro and in vivo experimental models. JAC1 increased the ubiquitination of HER2 at the K716 site through the E3 ubiquitin ligase SMURF1 which was due to the decreased expression of NEDD4, the E3 ubiquitin ligase of SMURF1. In conclusion, JAC1 suppresses the proliferation of HER2-positive breast cancer cells through the JWA triggered HER2 ubiquitination signaling. JAC1 may serve as a potential therapeutic agent for HER2-positive breast cancer.

scholarly journals A novel HSP90 inhibitor targeting the C-terminal domain attenuates trastuzumab resistance in HER2-positive breast cancer

2020 ◽  
Vol 19 (1) ◽  
Author(s):  
Jung Min Park ◽  
Yoon-Jae Kim ◽  
Soeun Park ◽  
Minsu Park ◽  
Lee Farrand ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Hsp90 Inhibitor ◽  
Trastuzumab Resistance ◽  
Her2 Positive ◽  
Mammosphere Formation ◽  
Her2 Positive Breast Cancer ◽  
Induced Apoptosis ◽  
Positive Breast Cancer

AbstractTrastuzumab resistance in HER2-positive breast cancer is associated with a poorer prognosis. HSP90 is thought to play a major role in such resistance, but N-terminal inhibitors of this target have had little success. We sought to investigate the utility of NCT-547, a novel, rationally-designed C-terminal HSP90 inhibitor in the context of overcoming trastuzumab resistance. NCT-547 treatment significantly induced apoptosis without triggering the heat shock response (HSR), accompanied by caspase-3/− 7 activation in both trastuzumab-sensitive and -resistant cells. NCT-547 effectively promoted the degradation of full-length HER2 and truncated p95HER2, while also attenuating hetero-dimerization of HER2 family members. The impairment of cancer stem-like traits was observed with reductions in ALDH1 activity, the CD24low/CD44high subpopulation, and mammosphere formation in vitro and in vivo. NCT-547 was an effective inhibitor of tumor growth and angiogenesis, and no toxic outcomes were found in initial hepatic and renal analysis. Our findings suggest that NCT-547 may have applications in addressing trastuzumab resistance in HER2-positive breast cancer.

Vacuoles Induced in Mammalian Cells by Helicobacter Cytotoxin are Acidic Organelles

1990 ◽  
Vol 48 (3) ◽  
pp. 168-169
Author(s):  
M. H. Chestnut ◽  
C. E. Catrenich
Keyword(s):  
Acridine Orange ◽  
Mammalian Cells ◽  
Laser Scanning ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Ulcer Disease ◽  
Gastroduodenal Disease ◽  
H Pylori

Helicobacter pylori is a non-invasive, Gram-negative spiral bacterium first identified in 1983, and subsequently implicated in the pathogenesis of gastroduodenal disease including gastritis and peptic ulcer disease. Cytotoxic activity, manifested by intracytoplasmic vacuolation of mammalian cells in vitro, was identified in 55% of H. pylori strains examined. The vacuoles increase in number and size during extended incubation, resulting in vacuolar and cellular degeneration after 24 h to 48 h. Vacuolation of gastric epithelial cells is also observed in vivo during infection by H. pylori. A high molecular weight, heat labile protein is believed to be responsible for vacuolation and to significantly contribute to the development of gastroduodenal disease in humans. The mechanism by which the cytotoxin exerts its effect is unknown, as is the intracellular origin of the vacuolar membrane and contents. Acridine orange is a membrane-permeant weak base that initially accumulates in low-pH compartments. We have used acridine orange accumulation in conjunction with confocal laser scanning microscopy of toxin-treated cells to begin probing the nature and origin of these vacuoles.

scholarly journals Oleanolic Acid’s Semisynthetic Derivatives HIMOXOL and Br-HIMOLID Show Proautophagic Potential and Inhibit Migration of HER2-Positive Breast Cancer Cells In Vitro

2021 ◽  
Vol 22 (20) ◽  
pp. 11273
Author(s):  
Natalia Magdalena Lisiak ◽  
Izabela Lewicka ◽  
Mariusz Kaczmarek ◽  
Jacek Kujawski ◽  
Barbara Bednarczyk-Cwynar ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Biological Activity ◽  
Cancer Cells ◽  
Oleanolic Acid ◽  
Breast Cancer Cells ◽  
Breast Cancer Patients ◽  
Her2 Positive ◽  
Her2 Positive Breast Cancer ◽  
Positive Breast Cancer

Approximately 20–30% of the diagnosed breast cancers overexpress the human epidermal growth factor receptor 2 (HER2). This type of cancer is associated with a more aggressive phenotype; thus, there is a need for the discovery of new compounds that would improve the survival in HER2-positive breast cancer patients. It seems that one of the most promising therapeutic cancer strategies could be based on the biological activity of pentacyclic triterpenes’ derivatives and the best-known representative of this group, oleanolic acid (OA). The biological activity of oleanolic acid and its two semisynthetic derivatives, methyl 3-hydroxyimino-11-oxoolean-12-en-28-oate (HIMOXOL) and 12α-bromo-3-hydroxyimonoolean-28→13-olide (Br-HIMOLID), was assessed in SK-BR-3 breast cancer cells (HER2-positive). Viability tests, cell cycle assessment, evaluation of apoptosis, autophagy, and adhesion/migration processes were performed using MTT, clonogenic, cytofluorometry, Western blot, and qPCR. Both derivatives revealed higher cytotoxicity in studied breast cancer cells than the maternal compound, OA. They also decreased cell viability, induced autophagy, and (when applied in sub-cytotoxic concentrations) decreased the migration of SK-BR-3 cells.This study is the first to report the cytostatic, proautophagic (mTOR/LC3/SQSTM/BECN1 pathway), and anti-migratory (integrin β1/FAK/paxillin pathway) activities of HIMOXOL and Br-HIMOLID in HER2-positive breast cancer cells.

The fate of medial edge epithelial cells during palatal fusion in vitro: an analysis by DiI labelling and confocal microscopy

Development ◽  
1992 ◽  
Vol 114 (2) ◽  
pp. 379-388 ◽  
Author(s):  
M.J. Carette ◽  
M.W. Ferguson
Keyword(s):  
Laser Scanning ◽  
Time Course ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Palatal Fusion ◽  
Morphological Criteria ◽  
Medial Edge ◽  
Mesenchymal Transformation

Fusion of bilateral shelves, to form the definitive mammalian secondary palate, is critically dependent on removal of the medial edge cells that constitute the midline epithelial seam. Conflicting views suggest that programmed apoptotic death or epithelial-mesenchymal transformation of these cells is predominantly involved. Due in part to the potentially ambiguous interpretation of static images and the notable absence of fate mapping studies, the process by which this is achieved has, however, remained mechanistically equivocal. Using an in vitro mouse model, we have selectively labelled palatal epithelia with DiI and examined the fate of medial edge epithelial (MEE) cells during palatal fusion by localisation using a combination of conventional histology and confocal laser scanning microscopy (CLSM). In dynamic studies using CLSM, we have made repetitive observations of the same palatal cultures in time-course investigations. Our results concurred with the established morphological criteria of seam degeneration; however, they provided no evidence of MEE cell death or transformation. Instead we report that MEE cells migrate nasally and orally out of the seam and are recruited into, and constitute, epithelial triangles on both the oral and nasal aspects of the palate. Subsequently these cells become incorporated into the oral and nasal epithelia on the surface of the palate. We hypothesize an alternative method of seam degeneration in vivo which largely conserves the MEE population by recruiting it into the nasal and oral epithelia.

Consequences of topoisomerase II inhibition in early embryogenesis of Drosophila revealed by in vivo confocal laser scanning microscopy

1993 ◽  
Vol 104 (4) ◽  
pp. 1175-1185 ◽  
Author(s):  
P. Buchenau ◽  
H. Saumweber ◽  
D.J. Arndt-Jovin
Keyword(s):  
Confocal Laser Scanning Microscopy ◽  
Laser Scanning ◽  
Topoisomerase Ii ◽  
Metaphase Plate ◽  
Laser Scanning Microscopy ◽  
Confocal Laser Scanning ◽  
Scanning Microscopy ◽  
Confocal Laser

The regulation of DNA topology by topoisomerase II from Drosophila melanogaster has been studied extensively by biochemical methods but little is known about its roles in vivo. We have performed experiments on the inhibition of topoisomerase II in living Drosophila blastoderm embryos. We show that the enzymatic activity can be specifically disrupted by microinjection of antitopoisomerase II antibodies as well as the epipodophyllotoxin VM26, a known inhibitor of topoisomerase II in vitro. By labeling the chromatin of live embryos with tetramethylrhodamine-coupled histones, the effects of inhibition on nuclear morphology and behaviour was followed in vivo using confocal laser scanning microscopy. Both the antibodies and the drug prevented or hindered the segregation of chromatin daughter sets at the anaphase stage of mitosis. In addition, high concentrations of inhibitor interfered with the condensation of chromatin and its proper arrangement into the metaphase plate. The observed effects yielded non-functional nuclei, which were drawn into the inner yolk mass of the embryo. Concurrently, undamaged nuclei surrounding the affected region underwent compensatory division, leading to the restoration of the nuclear population, and thereby demonstrating the regulative capacity of Drosophila blastoderm embryos.

scholarly journals Trastuzumab-Modified Gold Nanoparticles Labeled with 211At as a Prospective Tool for Local Treatment of HER2-Positive Breast Cancer

Nanomaterials ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 632 ◽  
Author(s):  
Łucja Dziawer ◽  
Agnieszka Majkowska-Pilip ◽  
Damian Gaweł ◽  
Marlena Godlewska ◽  
Marek Pruszyński ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Gold Nanoparticles ◽  
Local Treatment ◽  
Growth Factor Receptor ◽  
Dark Field ◽  
Her2 Positive ◽  
Her2 Positive Breast Cancer ◽  
Biological Studies ◽  
Positive Breast Cancer

Highly localized radiotherapy with radionuclides is a commonly used treatment modality for patients with unresectable solid tumors. Herein, we propose a novel α-nanobrachytherapy approach for selective therapy of human epidermal growth factor receptor 2 (HER2)-positive breast cancer. This uses local intratumoral injection of 5-nm-diameter gold nanoparticles (AuNPs) labeled with an α-emitter (211At), modified with polyethylene glycol (PEG) chains and attached to HER2-specific monoclonal antibody (trastuzumab). The size, shape, morphology, and zeta potential of the 5 nm synthesized AuNPs were characterized by TEM (Transmission Electron Microscopy) and DLS (Dynamic Light Scattering) techniques. The gold nanoparticle surface was modified by PEG and subsequently used for antibody immobilization. Utilizing the high affinity of gold for heavy halogens, the bioconjugate was labelled with 211At obtained by α irradiation of the bismuth target. The labeling yield of 211At was greater than 99%. 211At bioconjugates were stable in human serum. Additionally, in vitro biological studies indicated that 211At-AuNP-PEG-trastuzumab exhibited higher affinity and cytotoxicity towards the HER2-overexpressing human ovarian SKOV-3 cell line than unmodified nanoparticles. Confocal and dark field microscopy studies revealed that 211At-AuNP-PEG-trastuzumab was effectively internalized and deposited near the nucleus. These findings show promising potential for the 211At-AuNP-PEG-trastuzumab radiobioconjugate as a perspective therapeutic agent in the treatment of unresectable solid cancers expressing HER2 receptors.

Sign in / Sign up

Export Citation Format

Share Document