Search

BACKGROUND: Mucin 1 (MUC1), as an oncogene, plays an important role in the diagnosis of lung cancer. OBJECTIVE: To establish a double-antibody sandwich enzyme-linked immune sorbent assay (ELISA) kit for the detection of serum MUC1 in lung cancer patients. METHODS: Commercial mouse anti-human MUC1 monoclonal antibody and rabbit anti-human MUC1 polyclonal antibody were used to construct a double-antibody sandwich ELISA kit. The serum MUC1 levels in peripheral blood of lung disease patients and healthy individuals were detected by the double-antibody sandwich ELISA kit and CA15-3 kit, respectively. RESULTS: A double-antibody sandwich ELISA kit was successfully constructed, and the sensitivity was up to 0.5 μ g/l. The cut-off value for the serum MUC1 levels in the peripheral blood was 1.98 μ g/l, the sensitivity was 62.5%, the specificity was 100% and the Youden index was 0.6250 when detected by the double-antibody sandwich ELISA kit, while the sensitivity was 18.75%, the specificity was 100% and the Youden index was 0.1875 when detected by CA15-3 kit. CONCLUSION: The double-antibody sandwich ELISA kit is superior to the CA15-3 kit in the detection of serum MUC1 in lung cancer patients, suggesting an attractive applying of the double-antibody sandwich ELISA kit in the early diagnosis of lung cancer. [ABSTRACT FROM AUTHOR]

To investigate the mechanism of intracellular signal transduction mediated by activin receptors, the full-length gene encoding a novel activin receptor-interacting protein2a (ARIP2a) was identified from a mouse brain cDNA library. The sequences of ARIP2a and ARIP2, distribution of ARIP2a and ARIP2 mRNA in mouse tissues, and expression of ARIP2a and ARIP2 in activin-induced RAW264. 7 cell were compared, and the interaction between ARIP2a and ActRIIA was confirmed. The sequence analysis revealed that the full-length gene of ARIP2a, which composed of 1008 bp and encoded 153 amino acid residues, shared high sequence identity with ARIP2 except the position of the 99th amino acid. RT-PCR assay showed that ARIP2a mRNA was highly expressed in brain, pituitary and testis, and moderately in pancreas and ovary, but undetectable in other tissues. Whereas, ARIP2 mRNA was widely distributed in all mouse tissues that we tested. Moreover, expression of ARIP2a mRNA was significantly decreased in activin-stimulated RAW264.7 cells; however, the expression of ARIP2 mRNA was increased. Additionally, the interaction between ARIP2a and activin type IIA receptor (ActRIIA) was further demonstrated by mammalian two-hybrid assays and pull-down assays. Taken together, those results indicate that although ARIP2a is homologous to ARIP2, they are different in tissue distribution and responses to activin. ARIP2a could also interact with activin type II receptor as a novel member of ARIP family. [ABSTRACT FROM AUTHOR]

Myeloid-derived suppressor cells (MDSCs) are one of the major components of the tumor microenvironment (TME), and are the main mediators of tumor-induced immunosuppression. Recent studies have reported that the survival, differentiation and immunosuppressive activity of MDSCs are affected by the Toll-like receptor (TLR) signaling pathway. However, the regulatory effect of TLR signaling on MDSCs remains controversial. TLR-induced MDSC can acquire different immunosuppressive activities to influence the immune response that can be either beneficial or detrimental to cancer immunotherapy. The present review summarizes the effects of TLR signals on the number, phenotype and inhibitory activity of MDSCs, and their role in cancer immunotherapy, which cannot be ignored if effective cancer immunotherapies are to be developed for the immunosuppression of the TME., (Copyright: © Zhou et al.)

Recently, gold nanoparticles (AuNPs) have shown promising biological applications due to their unique electronic and optical properties. However, the potential toxicity of AuNPs remains a major hurdle that impedes their use in clinical settings. Mesoporous silica is very suitable for the use as a coating material for AuNPs and might not only reduce the cytotoxicity of cetyltrimethylammonium bromide-coated AuNPs but might also facilitate the loading and delivery of drugs. Herein, three types of rod-like gold-mesoporous silica nanoparticles (termed bare AuNPs, core-shell Au@mSiO2NPs, and Janus Au@mSiO2NPs) were specially designed, and the effects of these AuNPs on cellular uptake, toxic behavior, and mechanism were then systematically studied. Our results indicate that bare AuNPs exerted higher toxicity than the Au@mSiO2NPs and that Janus Au@mSiO2NPs exhibited the lowest toxicity in human breast cancer MCF-7 cells, consistent with the endocytosis capacity of the nanoparticles, which followed the order, bare AuNPs > core-shell Au@mSiO2NPs > Janus Au@mSiO2NPs. More importantly, the AuNPs-induced apoptosis of MCF-7 cells exhibited features that were characteristic of intracellular reactive oxygen species (ROS) generation, activation of c-Jun-N-terminal kinase (JNK) phosphorylation, an enhanced Bax-to-Bcl-2 ratio, and loss of the mitochondrial membrane potential. Simultaneously, cytochrome c was released from mitochondria, and the caspase-3/9 cascade was activated. Moreover, both ROS scavenger (N-acetylcysteine) and JNK inhibitor (SP600125) partly blocked the induction of apoptosis in all AuNPs-treated cells. Taken together, these findings suggest that all AuNPs induce apoptosis through the ROS-/JNK-mediated mitochondrial pathway. Thus, Janus Au@mSiO2NPs exhibit the potential for applications in biomedicine, thus aiding the clinical translation of AuNPs.

Objective: To detect the effects of 17β-estradiol (E2) on the expression of calbindin-D9k (CaBP-9k) in pituitary GH3 cells, and to determine the antagonistic effect of a selective estrogen receptor (ER) antagonist (ICI 182 780) on CaBP-9k expression., Methods: A rat pituitary prolactinoma cell line (GH3 cells) was used in an in vitro model. The localization of CaBP-9k in GH3 cells was observed by immunofluorescence. GH3 cells were cultured with the addition of E2 medium for 24 hours. The levels of CaBP-9k mRNA and protein expression in different groups were analyzed by RT-PCR and Western blot analysis. The ER antagonist, ICI 182 780, was added to GH3 cells before E2 (10(-8) M) at a concentration of 10(-6) M to investigate the regulation of an ER-mediated pathway on CaBP-9k expression., Results: E2 had a stimulatory effect on CaBP-9k expression of GH3 cells in a dose-dependent manner; the level of CaBP-9k expression was higher when treated with a higher concentration of E2. ICI 182 780 suppressed the stimulatory effect of E2 on CaBP-9k expression in GH3 cells. The level of CaBP-9k expression was significantly reduced by co-administration of E2 with ICI 182 780 in GH3 cells. The immunoprecipitation results confirmed that CaBP-9k interacts directly with ERα, and E2 increases the interaction between CaBP-9k and ERα., Conclusion: Estrogen induces CaBP-9k expression via an ERα-mediated pathway and CaBP-9k directly combines with ERα, suggesting that CaBP-9k is involved in the biological effects mediated by an ER pathway in GH3 cells.