Tumor initiation and growth depend on its microenvironment in which cancer-associated fibroblasts (CAFs) in tumor stroma play an important role. Prostaglandin E2 (PGE2) and interleukin (IL)-6 signal pathways are involved in the crosstalk between tumor and stromal cells. However, how PGE2-mediated signaling modulates this crosstalk remains unclear. Here, we show that microRNA (miR)-149 links PGE2 and IL-6 signaling in mediating the crosstalk between tumor cells and CAFs in gastric cancer (GC). miR-149 inhibited fibroblast activation by targeting IL-6 and miR-149 expression was substantially suppressed in the CAFs of GC. miR-149 negatively regulated CAFs and their effect on GC development both in vitro and in vivo. CAFs enhanced epithelial-to-mesenchymal transition (EMT) and the stem-like properties of GC cells in a miR-149-IL-6-dependent manner. In addition to IL-6, PGE2 receptor 2 (PTGER2/EP2) was revealed as another potential target of miR-149 in fibroblasts. Furthermore, H. pylori infection, a leading cause of human GC, was able to induce cyclooxygenase-2 (COX-2)/PGE2 signaling and to enhance PGE2 production, resulting in the hypermethylation of miR-149 in CAFs and increased IL-6 secretion. Our findings indicate that miR-149 mediates the crosstalk between tumor cells and CAFs in GC and highlight the potential of interfering miRNAs in stromal cells to improve cancer therapy.
Imatinib mesylate (IM), a targeted competitive inhibitor of the BCR-ABL tyrosine kinase, has revolutionized the clinical treatment of chronic myeloid leukemia (CML). However, resistance and intolerance are still a challenge in the treatment of CML. Autophagy has been proposed to play a role in IM resistance. To investigate the anti-leukemic activity of specific and potent autophagy inhibitor-1 (spautin-1) in CML, we detected its synergistic effect with IM in K562 and CML cells. Our results showed that spautin-1 markedly inhibited IM-induced autophagy in CML cells by downregulating Beclin-1. Spautin-1 enhanced IM-induced CML cell apoptosis by reducing the expression of the anti-apoptotic proteins Mcl-1 and Bcl-2. We further demonstrated that the pro-apoptotic activity of spautin-1 was associated with activation of GSK3β, an important downstream effector of PI3K/AKT. The findings indicate that the autophagy inhibitor spautin-1 enhances IM-induced apoptosis by inactivating PI3K/AKT and activating downstream GSK3β, leading to downregulation of Mcl-1 and Bcl-2, which represents a promising approach to improve the efficacy of IM in the treatment of patients with CML.
The application of perfluorocarbon liquids has been well acclaimed in vitreoretinal surgery. Its unique physical properties make it an ideal intraoperative tool to improve the efficiency and safety of surgical procedures in complicated cases. The main functions of perfluorocarbon liquids in vitreoretinal surgery include relocating and fixing the detached retina, displacing the subretinal and subchoroidal to fluid anteriorly, revealing proliferative vitreous retinopathy (PVR) for further maneuvers, protecting the macula from exposure to chemicals with potential toxicity, and assisting the removal of foreign body. The related clinical applications include retinal detachment with severe proliferative vitreoretinopathy, giant tear, diabetic retinopathy (DR), retinopathy of prematurity (ROP), and posterior dislocated crystalline and intraocular lenses. The application of perfluorocarbon liquids has been expended over the past fewer years. Several PFCLs related ocular inflammations have been observed in in vitro studies, animal studies, and clinical follow-up. The complete removal of PFCLs is recommended at the end of the surgery in most cases.
Background
Pneumocystis jirovecii pneumonia (PJP) and pulmonary cytomegalovirus (CMV) infection are common opportunistic infections among immunocompromised patients. However, few studies have evaluated their co-infection, especially among non-HIV patients. Therefore, we aimed to evaluate the outcomes and prognostic factors among non-HIV patients with PJP according to their CMV infection status.MethodsThis retrospective study evaluated non-HIV patients who were diagnosed with PJP between January 2009 and January2016.The patients were classified and compared according to their pulmonary CMV infection status (positive infection: bronchoalveolar lavage fluid [BALF] CMV DNA loads of >500copies/mL).ResultsAmong 70 non-HIV patients with PJP, we identified 38 patients (54.3%) with pulmonary CMV infection. There was no significant difference in the mortality rates for the two groups (p = 0.15). Pulmonary CMV infection was significantly more common among patients who were receiving glucocorticoids and immunosuppressants, compared to corticosteroids only (p = 0.02). Pulmonary CMV infection was also significantly associated with severe dyspnea, a lower PaO2/FiO2, and the presence of centrilobular nodules (p = 0.008). Higher CMV DNA loads in the BALF were positively associated with mortality (p = 0.012).ConclusionsCombined therapy using corticosteroids and other immunosuppressants may be a risk factor for pulmonary CMV co-infection among patients with PJP. In addition, CMV pneumonia should be considered when centrilobular nodules and/or severe hypoxemia are observed in non-HIV patients with PJP. Furthermore, antiviral treatment should be promptly initiated for patients with a high CMV DNA load in BALF, based on their poor prognosis.
BackgroundHIV-negative, CD20-negative de novo diffuse large B-cell lymphoma (DLBCL) patients has rarely been reported. To elucidate the nature of this entity, we retrospectively reviewed the data of 1,456 consecutive de novo DLBCL patients who were treated at Sun Yat-Sen University Cancer Center between January 1999 and March 2011.MethodsThe pathologic characteristics of CD20-negative patients, clinical features, response to initial treatment, and outcomes of 28 patients with available clinical data (n = 21) were reviewed. Then, a matched case-control (1:3) analysis was performed to compare patients with CD20-negative and -positive DLBCL.ResultsThe median age of the 28 CD20-negative DLBCL patients was 48 years, with a male-female ratio of 20:8. Seventeen of 22 (77.3%) CD20-negative DLBCL cases were of the non-germinal centre B-cell (non-GCB) subtype. High Ki67 expression (≥80%), an index of cell proliferation, was demonstrated in 17 of 24 (70.8%) cases. Extranodal involvement (≥ 1 site) was observed in 76.2% of the patients. Following initial therapy, 9 of 21 (42.9%) cases achieved complete remission, 4 (19%) achieved partial remission, 1 (4.8%) had stable disease, and 7 (33.3%) had disease progression. The median overall survival was 23 months. The 3-year progression-free survival (PFS) and overall survival (OS) rates were 30.5% and 35%, respectively. A matched case-control analysis showed that patients with CD20-negative and -positive DLBCL did not exhibit a statistically significant difference with respect to the main clinical characteristics (except extranodal involvement), whereas the patients with CD20-positive DLBCL had a better survival outcome with 3-year PFS (P = 0.008) and OS (P = 0.008) rates of 52% and 74.1%, respectively.ConclusionsThis study suggests that HIV-negative, CD20-negative de novo DLBCL patients have a higher proportion of non-GCB subtype, a higher proliferation index, more frequent extranodal involvement, a poorer response, and a poorer prognosis to conventional treatment compared to patients with CD20-positive DLBCL. Further studies are warranted to investigate new target and optimal therapy of CD20-negative de novo DLBCL.
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