T790M may not be a rare event before or after TKI therapy in patients with NSCLC with EGFR-activating mutations. The pretreatment T790M mutation was associated with shorter PFS with EGFR TKI therapy in patients with NSCLC.
There are no antivirals or vaccines available to treat Enterovirus 71 (EV71) infections. Although the type I interferon response, elicited upon virus infection, is critical to establishing host antiviral innate immunity, EV71 fails to induce this response efficiently. Here we provide new insights into potential anti-EV71 therapy by showing that neutralization of EV71-induced miR-146a prevents death in mice by restarting the production of type I interferon. EV71 infection upregulates miR-146a, which targets IRAK1 and TRAF6 involved in TLR signalling and type I interferon production. We further identify AP1 as being responsible for the EV71-induced expression of miR-146a. Surprisingly, knocking out miR-146a or neutralizing virus-induced miR-146a by specific antagomiR restores expressions of IRAK1 and TRAF6, augments IFNb production, inhibits viral propagation and improves survival in the mouse model. Our results suggest that enterovirus-induced miR-146a facilitates viral pathogenesis by suppressing IFN production and provide a clue to developing preventive and therapeutic strategies for enterovirus infections.
Viruses rely on the host translation machinery to complete their life cycles. Picornaviruses use an internal ribosome entry site to initiate cap-independent protein translation and in parallel host cap-dependent translation is shut off. This process is thought to occur primarily via cleavage of host translation initiation factors eIF4GI and eIF4GII by viral proteases. Here we describe another mechanism whereby miR-141 induced upon enterovirus infection targets the cap-dependent translation initiation factor, eIF4E, for shutoff of host protein synthesis. Knockdown of miR-141 reduces viral propagation, and silencing of eIF4E can completely reverse the inhibitory effect of the miR-141 antagomiR on viral propagation. Ectopic expression of miR-141 promotes the switch from cap-dependent to cap-independent translation. Moreover, we identified a transcription factor, EGR1, which is partly responsible for miR-141 induction in response to enterovirus infection. Our results suggest that upregulation of miR-141 upon enterovirus infection can facilitate viral propagation by expediting the translational switch.
Background. Patients with neuroendocrine‐related tumors and paraneoplastic encephalomyelitis (PEM) or paraneoplastic sensory neuronopathy (PSN) develop high titers of antibodies, called anti‐Hu, against neuronal proteins expressed in their tumors, usually small cell lung cancer (SCLC). These tumors appear to be more indolent than those not associated with anti‐Hu antibodies. The aims of this study were to determine 1) if patients with neuroblastoma (N8) also have anti‐Hu antibodies, 2) the correlation between antibody titer and survival, and 3) if coexpression of Hu antigens and major histocompatibility proteins (MHC) by the tumor correlates with the development of anti‐Hu associated PEM/PSN.
Methods. Using immunohistochemistry and Western blot analysis, the sera of 109 patients with NB whose neurologic condition was concealed at the time of the study were examined for the presence of anti‐Hu antibodies. The expression of Hu antigens and MHC proteins in 50 nonselected NB and 26 SCLC (16 known to be from seropositive and 10 from seronegative patients) was examined using immunohistochemistry.
Results. Four Stage 4 NB patients were seropositive and had longer survival (median 86 months) than 71 seronegative patients in the same age group and with the same tumor stage (median survival, 28.5 months). Seventy‐eight percent of NB and all SCLC expressed Hu antigens. Overall, 17 of 20 tumors from seropositive patients expressed both Hu and MHC Class I proteins, but only 4 of 30 tumors from seronegative patients expressed both proteins (P < 0.0001).
Conclusions. 1) Some patients with NB develop anti‐Hu antibodies; a search for that type of tumor is indicated in seropositive children, 2) most NBs and SCLCs express Hu antigens but only a few are associated with anti‐Hu antibodies, and 3) Class I MHC expressed by some Hu antigen‐bearing tumors may play a role in the development of anti‐Hu associated PEM/PSN.
Leukocyte cell-derived chemotoxin 2 (LECT2) has been shown to act as a tumor suppressor in hepatocellular carcinoma (HCC). However, the underlying mechanism has not yet been completely defined. Here, we employ a LECT2-affinity column plus liquid chromatography coupled with tandem mass spectrometry to identify LECT2-binding proteins and found that MET receptor strongly interacted with LECT2 protein. Despite the presence of hepatocyte growth factor, the LECT2 binding causes an antagonistic effect to MET receptor activation through recruitment of protein tyrosine phosphatase 1B. The antagonistic effect of LECT2 on MET activation also mainly contributes to the blockage of vascular invasion and metastasis of HCC. Furthermore, serial deletions and mutations of LECT2 showed that the HxGxD motif is primarily responsible for MET receptor binding and its antagonistic effects. Conclusion: These findings reveal a novel, specific inhibitory function of LECT2 in HCC by the direct binding and inactivation of MET, opening a potential avenue for treating MET-related liver cancer. (HEPATOLOGY 2014;59:974-985)
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.