This study aims to evaluate the feasibility of a label-free nanobiosensor based on blood plasma surface-enhanced Raman spectroscopy (SERS) method for exploring variability of different tumor (T) stages in nasopharyngeal cancer (NPC). Au nanoparticles as the SERS-active nanostructures were directly mixed with human blood plasma to enhance the Raman scattering signals. High quality SERS spectra can be acquired from blood plasma samples belong to 60 healthy volunteers, 25 NPC patients with T1 stage and 75 NPC patients with T2–T4 stage. A diagnostic accuracy of 83.5% and 93.3%, respectively, can be achieved for classification between early T (T1) stage cancer and normal; and advanced T (T2–T4) stage cancer and normal blood groups. This exploratory study demonstrates that the nanobiosensor based on SERS technique in conjunction with PCA-LDA has great potential as a clinical complement for different T stages detection in nasopharyngeal cancer.
SR-A (class A macrophage scavenger receptor) is a transmembrane receptor that can bind many different ligands, including modified lipoproteins that are relevant to the development of vascular diseases. However, the precise endocytic pathways of SR-A/mediated ligands internalization are not fully characterized. In this study, we show that the SR-A/ligand complex can be endocytosed by both clathrin-and caveolae-dependent pathways. Internalizations of SR-A-lipoprotein (such as acLDL) complexes primarily go through clathrin-dependent endocytosis. In contrast, macrophage apoptosis triggered by SR-A-fucoidan internalization requires caveolae-dependent endocytosis. The caveolae-dependent process activates p38 kinase and JNK signaling, whereas the clathrin-mediated endocytosis elicits ERK signaling. Our results suggest that different SR-A endocytic pathways have distinct functional consequences due to the activation of different signaling cascades in macrophages.
Background Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are being wildly used as target therapy in non-small-cell lung cancer (NSCLC). However, NSCLC patients with wild-type EGFR and KRAS mutation are primary resistant to EGFR-TKIs such as gefitinib. Curcumin has been known as a potential therapeutic agent for several major human cancers. In this study, we investigated the effect of curcumin on the reversal of gefitinib resistance in NSCLC cells as well as their molecular bases. Methods H157 (wild-type EGFR and KARS mutation) and H1299 (wild-type EGFR and HRAS mutation) cells were treated with gefitinib or curcumin alone, or the two combination, and then cell viability, EGFR activity, expressions of Sp1 and Sp1-dependent proteins and receptor tyrosine kinases, markers of autophagy and apoptosis were examined by using CCK-8, colony formation, immunoblot, quantitative PCR, immunofluoscence, and flow cytometry assays. Also xenograft experiments were conduced to test the synergism of curcumin to gefitinib. Results Our results showed that curcumin significantly enhanced inhibitory effect of gefitinib on primary gefitinib-resistant NSCLC cell lines H157 and H1299. Combination treatment with curcumin and gefitinib markedly downregulated EGFR activity through suppressing Sp1 and blocking interaction of Sp1 and HADC1, and markedly suppressed receptor tyrosine kinases as well as ERK/MEK and AKT/S6K pathways in the resistant NSCLC cells. Meanwhile, combination treatment of curcumin and gefitinib caused dramatic autophagy induction, autophagic cell death and autophagy-mediated apoptosis, compared to curcumin or gefitinib treatment alone, as evidenced by the findings that curcumin and gefitinib combination treatment-produced synergistic growth inhibition and apoptosis activation can be reversed by pharmacological autophagy inhibitors (Baf A1 or 3-MA) or knockdown of Beclin-1 or ATG7, also can be partially returned by pan-caspase inhibitor (Z-VAD-FMK) in H157 and H1299 cells. Xenograft experiments in vivo yielded similar results. Conclusions These data indicate that the synergism of curcumin on gefitinib was autophagy dependent. Curcumin can be used as a sensitizer to enhance the efficacy of EGFR-TKIs and overcome the EGFR-TKI resistance in NSCLC patients with wild-type EGFR and/or KRAS mutation. Electronic supplementary material The online version of this article (10.1186/s13046-019-1234-8) contains supplementary material, which is available to authorized users.
BackgroundThe receptor tyrosine kinase-like orphan receptors (ROR) family contains the atypical member ROR1, which plays an oncogenic role in several malignant tumors. However, the clinical potentials and underlying mechanisms of ROR1 in gastric cancer progression remain largely unknown. In this study, we validated the microRNA-mediated gene repression mechanism involved in the role of ROR1.MethodsBioinformatic prediction, luciferase reporter assay, quantitative real-time PCR (qRT-PCR) and western blotting were used to reveal the regulatory relationship between miR-27b-3p and ROR1. The expression patterns of miR-27b-3p and ROR1 in human gastric cancer (GC) specimens and cell lines were determined by microRNA RT-PCR and western blotting. Cell proliferation, colony formation assay in soft agar in vitro and tumorigenicity in vivo were performed to observe the effects of downregulation and upregulation miR-27b-3p expression on GC cell phenotypes.ResultsmiR-27b-3p suppressed ROR1 expression by binding to the 3’UTR of ROR1 mRNA in GC cells. miR-27b-3p was significantly downregulated and reversely correlated with ROR1 protein levels in clinical samples. Analysis of the clinicopathological significance showed that miR-27b-3p and ROR1 were closely correlated with GC characteristics. Ectopic miR-27b-3p expression suppressed cell proliferation, colony formation in soft agar, xenograft tumors of GC cells. By contrast, miR-27b-3p knockdown enhanced these malignant behaviors. Our studies further revealed that the c-Src/STAT3 signaling pathway was involved in miR-27b-3p-ROR1-mediated cell proliferation regulation.ConclusionsThese results show that miR-27b-3p suppresses ROR1 expression through the binding site in the 3’UTR inhibiting the cell proliferation. These findings indicate that miR-27b-3p exerts tumor-suppressive effects in GC through the suppression of oncogene ROR1 expression and suggest a therapeutic application of miR-27b-3p in GC.
Cisplatin remains to be primary chemotherapeutic drug for gastric cancer patients, especially for advanced stage ones. However, primary or acquired resistance often occurs with the mechanisms being not well understood, which results in relapse of the cancer and poor survival. Herein, we found that HER2 upregulation was associated with cisplatin resistance. We observed that cisplatin-resistant gastric cancer cells underwent a morphological change similar to epithelial-mesenchymal transition (EMT) which is mediated by HER2 overexpression. When specific monoclonal antibody Herceptin, small molecular targeted drug CP724714, or small interfering RNA against HER2 was applied, the EMT-like phenotypic change was dramatically reversed. More importantly, the IC50 and Resistance Index of resistant gastric cancer cells to cisplatin were also decreased by any of these treatments.We demonstrated that expression and amplification of HER2 positively correlated with expression of EMT-related transcription factor Snail in gastric cancer tissues. Furthermore, for the first time, we found that HER2/Snail double positive gastric cancer patients had poorer survival than single positive or double negative counterparts, which provided experimental evidence for the necessity of HER2/Snail double testing in gastric cancer. In conclusion, this study provides some clues of the association of cisplatin resistance with HER2 upregulation-induced EMT in gastric cancer cells.
A surface-enhanced Raman spectroscopy (SERS) based on silver nanoparticle technology was applied to analyze and classify human blood plasma with the aim to develop a simple and label-free blood test for esophageal cancer detection. High quality SERS spectra in the range of 400-1800 cm(-1) can be acquired from 36 esophageal cancer patients and 50 healthy volunteers' blood plasma samples. Tentative assignments of the SERS bands indicated specific biomolecular changes associated with cancer transformation, including an increase in the relative amounts of nucleic acid and phenylalanine, a decrease in the percentage of saccharide and proteins contents in the cancer blood plasma compared to that of healthy subjects. Furthermore, both SVM and PCA-LDA diagnostic algorithm were employed to analyze and classify the obtained blood plasma SERS spectra between normal and cancer plasma with a high diagnostic accuracy (around 90%). This exploratory work demonstrates that the label-free plasma SERS analysis technique in conjunction with SVM and PCA-LDA diagnostic algorithms has great potential for improving esophageal cancer detection and screening.
Obstructive sleep apnea syndrome (OSAS) is associated with many cardiovascular disorders such as heart failure, hypertension, atherosclerosis, and arrhythmia and so on. Of the many associated factors, chronic intermittent hypoxia (CIH) in particular is the primary player in OSAS. To assess the effects of CIH on cardiac function secondary to OSAS, we established a model to study the effects of CIH on Wistar rats. Specifically, we examined the possible underlying cellular mechanisms of hypoxic tissue damage and the possible protective role of adiponectin against hypoxic insults. In the first treatment group, rats were exposed to CIH conditions (nadir O2, 5–6%) for 8 hours/day, for 5 weeks. Subsequent CIH-induced cardiac dysfunction was measured by echocardiograph. Compared with the normal control (NC) group, rats in the CIH-exposed group experienced elevated levels of left ventricular end-systolic dimension and left ventricular end-systolic volume and depressed levels of left ventricular ejection fraction and left ventricular fractional shortening (p<0.05). However, when adiponectin (Ad) was added in CIH + Ad group, we saw a rescue in the elevations of the aforementioned left ventricular function (p<0.05). To assess critical cardiac injury, we detected myocardial apoptosis by Terminal deoxynucleotidyl transfer-mediated dUTP nick end-labeling (TUNEL) analysis. It was showed that the apoptosis percentage in CIH group (2.948%) was significantly higher than that in NC group (0.4167%) and CIH + Ad group (1.219%) (p<0.05). Protein expressions of cleaved caspase-3, cleaved caspase-9, and cleaved-caspase-12 validated our TUNEL results (p<0.05). Mechanistically, our results demonstrated that the proteins expressed with endoplasmic reticulum stress and the expression of reactive oxygen species (ROS) were significantly elevated under CIH conditions, whereas Ad supplementation partially decreased them. Overall, our results suggested that Ad augmentation could improve CIH-induced left ventricular dysfunction and associated myocardial apoptosis by inhibition of ROS-dependent ER stress.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.