Two new isomeric modified tripeptides, aspergillamides C and D (compounds 1 and 2), together with fifteen known compounds (compounds 3-17), were obtained from the marine sponge-derived fungus Aspergillus terreus SCSIO 41008. The structures of the new compounds, including absolute configurations, were determined by extensive analyses of spectroscopic data (NMR, MS, UV, and IR) and comparisons between the calculated and experimental electronic circular dichroism (ECD) spectra. Butyrolactone I (compound 11) exhibited strong inhibitory effects against Mycobacterium tuberculosis protein tyrosine phosphatase B (MptpB) with the IC being 5.11 ± 0.53 μmol·L, and acted as a noncompetitive inhibitor based on kinetic analysis.
4-Butyrolactone ; analogs & derivatives ; chemistry ; isolation & purification ; pharmacology ; Animals ; Aspergillus ; chemistry ; Chemistry Techniques, Analytical ; Dipeptides ; chemistry ; isolation & purification ; pharmacology ; Enzyme Inhibitors ; chemistry ; isolation & purification ; pharmacology ; Indoles ; chemistry ; isolation & purification ; pharmacology ; Molecular Structure ; Mycobacterium tuberculosis ; drug effects ; Peptides ; chemistry ; isolation & purification ; pharmacology ; Polyketides ; chemistry ; isolation & purification ; pharmacology ; Porifera ; microbiology ; Protein Tyrosine Phosphatases ; chemistry

PURPOSE: Rearrangement of the proto-oncogene rearranged during transfection (RET) has been newly identified potential driver mutation in lung adenocarcinoma. Clinically available tyrosine kinase inhibitors (TKIs) target RET kinase activity, which suggests that patients with RET fusion genes may be treatable with a kinase inhibitor. Nevertheless, the mechanisms of resistance to these agents remain largely unknown. Thus, the present study aimed to determine whether epidermal growth factor (EGF) and hepatocyte growth factor (HGF) trigger RET inhibitor resistance in LC-2/ad cells with CCDC6-RET fusion genes. MATERIALS AND METHODS: The effects of EGF and HGF on the susceptibility of a CCDC6-RET lung cancer cell line to RET inhibitors (sunitinib, E7080, vandetanib, and sorafenib) were examined. RESULTS: CCDC6-RET lung cancer cells were highly sensitive to RET inhibitors. EGF activated epidermal growth factor receptor (EGFR) and triggered resistance to sunitinib, E7080, vandetanib, and sorafenib by transducing bypass survival signaling through ERK and AKT. Reversible EGFR-TKI (gefitinib) resensitized cancer cells to RET inhibitors, even in the presence of EGF. Endothelial cells, which are known to produce EGF, decreased the sensitivity of CCDC6-RET lung cancer cells to RET inhibitors, an effect that was inhibited by EGFR small interfering RNA (siRNA), anti-EGFR antibody (cetuximab), and EGFR-TKI (Iressa). HGF had relatively little effect on the sensitivity to RET inhibitors. CONCLUSION: EGF could trigger resistance to RET inhibition in CCDC6-RET lung cancer cells, and endothelial cells may confer resistance to RET inhibitors by EGF. E7080 and other RET inhibitors may provide therapeutic benefits in the treatment of RET-positive lung cancer patients.
Adenocarcinoma/drug therapy/*genetics ; Cell Line, Tumor ; Cetuximab/pharmacology ; Drug Resistance, Neoplasm/drug effects/*genetics ; Epidermal Growth Factor/metabolism/*pharmacology ; *Gene Rearrangement ; Hepatocyte Growth Factor/*pharmacology ; Humans ; Indoles/pharmacology ; Lung Neoplasms/drug therapy/*genetics ; MAP Kinase Signaling System ; *Mutation ; Niacinamide/analogs & derivatives/pharmacology ; Phenylurea Compounds/pharmacology ; Piperidines/pharmacology ; Protein Kinase Inhibitors/therapeutic use ; Proto-Oncogene Proteins c-ret/*antagonists & inhibitors/genetics ; Pyrroles/pharmacology ; Quinazolines/pharmacology ; RNA, Small Interfering/pharmacology ; Receptor, Epidermal Growth Factor/genetics/metabolism ; Signal Transduction/drug effects ; fms-Like Tyrosine Kinase 3/metabolism

RNA helicases are involved in almost every aspect of RNA, from transcription to RNA decay. DExD/H-box helicases comprise the largest SF2 helicase superfamily, which are characterized by two conserved RecA-like domains. In recent years, an increasing number of unexpected functions of these proteins have been discovered. They play important roles not only in innate immune response but also in diseases like cancers and chronic hepatitis C. In this review, we summarize the recent literatures on one member of the SF2 superfamily, the DEAD-box protein DDX41. After bacterial or viral infection, DNA or cyclic-di-GMP is released to cells. After phosphorylation of Tyr414 by BTK kinase, DDX41 will act as a sensor to recognize the invaders, followed by induction of type I interferons (IFN). After the immune response, DDX41 is degraded by the E3 ligase TRIM21, using Lys9 and Lys115 of DDX41 as the ubiquitination sites. Besides the roles in innate immunity, DDX41 is also related to diseases. An increasing number of both inherited and acquired mutations in DDX41 gene are identified from myelodysplastic syndrome and/or acute myeloid leukemia (MDS/AML) patients. The review focuses on DDX41, as well as its homolog Abstrakt in Drosophila, which is important for survival at all stages throughout the life cycle of the fly.
Agammaglobulinaemia Tyrosine Kinase ; Animals ; Bacterial Infections ; genetics ; immunology ; Cyclic GMP ; analogs & derivatives ; genetics ; immunology ; DEAD-box RNA Helicases ; genetics ; immunology ; Drosophila Proteins ; genetics ; immunology ; Drosophila melanogaster ; Humans ; Leukemia, Myeloid, Acute ; genetics ; immunology ; Mutation ; Myelodysplastic Syndromes ; genetics ; immunology ; Nuclear Proteins ; genetics ; immunology ; Protein-Tyrosine Kinases ; genetics ; immunology ; Virus Diseases ; genetics ; immunology

Adult ; Female ; Humans ; Leukemia, Myeloid, Acute ; enzymology ; genetics ; Mutation ; genetics ; Niacinamide ; adverse effects ; analogs & derivatives ; Phenylurea Compounds ; adverse effects ; Tandem Repeat Sequences ; genetics ; Thyroiditis ; chemically induced ; enzymology ; genetics ; fms-Like Tyrosine Kinase 3 ; genetics

OBJECTIVETo study the efficacy and safety of sorafenib combined with low dose cytarabine for treating patients with FLT3(+) relapsed and refractory acute myeloid leukemia (FLT3(+) RR-AML).

METHODSSeven patients with FLT3(+) RR-AML were treated with sorafenib and low dose cytarabine. The curative rate and adverse effects were observed in these patients.

RESULTSOut of 7 RR-AML patients after treatment, 5 patients achieved complete remission (CR), 2 patients achieved partial remission (PR), and the overall response rate (ORR) after one course of therapy was 100%. No severe bleeding, nausea, vomiting and other side effects were found in these patients.

CONCLUSIONSorafenib combined with low dose cytarabine can effectively induce the remission of FLT3(+) RR-AML patients, and is worth for further clinical trails to verify its safty and efficiency.

Cytarabine ; therapeutic use ; Humans ; Leukemia, Myeloid, Acute ; drug therapy ; Niacinamide ; analogs & derivatives ; therapeutic use ; Phenylurea Compounds ; therapeutic use ; Recurrence ; Remission Induction ; Treatment Outcome ; fms-Like Tyrosine Kinase 3 ; metabolism

Objective To study the effects of Chinese medicinal compound Jinmaitong(JMT) on the expressions of nitrotyrosine (NT) and nerve growth factor (NGF) in dorsal root ganglia of diabetic rats. Methods Experimental rat diabetic models were established by the intraperitoneal injection of streptozotocin. Rat models were then randomly divided into four groups including normal control group (Con group),diabetes mellitus group (DM group),Jinmaitong group(JMT group)(treated with JMT similar to the fifteen-fold dose of adult recommended dosage),and taurine group(Tau group)(treated with Taurine similar to the fifteen-fold dose of adult recommended dosage),with 10 rats in each group. The Con and DM groups were treated with distilled water at a daily dose of 1 ml/100 g. All rats were given intragastric administration for 16 weeks and then killed. Body weight and blood glucose were detected before and at the 4th,8th,12th,and 16th week after treatment. The pain threshold to mechanical stimulation with von Frey filament were carried out before death. The expressions of NT and NGF in dorsal root ganglion were detected by immunohistochemistry and Western blot analysis,respectively. Results Immunohistochemistry showed that the average optical density (AOD) of NT expression in DM group were significantly higher than those in control group (P=0.000),and the AOD of NGF was significantly lower than the control group (P=0.006).The AOD of NT(P=0.000,P=0.000) in both treatment groups decreased significantly and the AOD of NGF(P=0.000, P=0.004)significantly increased compared with DM group. The AOD of NT in JMT group was significantly lower than Tau group (P=0.004). Western blot analysis showed that the protein level of NT in DM group was significantly higher than that in control group (P=0.000),and the protein level of NGF was significantly lower than that in control group (P=0.000). Compared with the DM group,the protein level of NT in both treatment groups significantly decreased (P=0.001,P=0.000),and the protein level of NGF increased significantly (P=0.000,P=0.001). Conclusion Traditional Chinese medicine JMT can obviously up-regulate the expressions of NGF and reduce the NT levels in dorsal root ganglia of diabetic rats.
Animals ; Blood Glucose ; Body Weight ; Diabetes Mellitus, Experimental ; drug therapy ; pathology ; Drugs, Chinese Herbal ; pharmacology ; Ganglia, Spinal ; drug effects ; metabolism ; Immunohistochemistry ; Nerve Growth Factor ; metabolism ; Pain Threshold ; Random Allocation ; Rats ; Tyrosine ; analogs & derivatives ; metabolism

OBJECTIVETo analyze the effect of sorafenib as salvage therapy used before and/or after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in refractory relapsed FLT3-positive acute myeloid leukemia (AML).

METHODSA total of 16 patients with refractory relapsed FLT3-positive AML, including 10 refractory relapsed pre-transplantation and 6 relapsed after allo-HSCT, were enrolled in this retrospective study. Sorafenib treatment protocols included sorafenib in combination with chemotherapy inducing remission, and sorafenib monotherapy as mauntenance treatment after complete remission (CR).

RESULTSThirteen of the 16 patients achieved CR after one or two courses of induction therapy, including 7 refractory relapsed pre-transplantation and 6 relapsed after allo-HSCT. With a median follow up of 472 (range, 59-1569) days post-transplantation, 12 patients survived and 4 died. Causes of death included leukemia relapse (n=3) and acute graft-versus-host disease (n=1). The 2-year overall and disease-free survival post-transplantation of the 16 patients were (75.0±10.8) % and (50.5±13.7) % respectively. The main side effect of sorafenib was the skin rash. The incidence of rash was lower in the patients used sorafenib pre-transplantation than those post-transplantation (30.0% vs 75.0%, P=0.043).

CONCLUSIONSorafenib used as salvage therapy befor and/or after transplantation for refractory relapsed FLT3-positive AML could reduce the relapse rate and improve the survival.

Antineoplastic Agents ; therapeutic use ; Disease-Free Survival ; Graft vs Host Disease ; Hematopoietic Stem Cell Transplantation ; Humans ; Induction Chemotherapy ; Leukemia, Myeloid, Acute ; genetics ; therapy ; Mutation ; Niacinamide ; analogs & derivatives ; therapeutic use ; Phenylurea Compounds ; therapeutic use ; Recurrence ; Remission Induction ; Retrospective Studies ; Salvage Therapy ; Treatment Outcome ; fms-Like Tyrosine Kinase 3 ; genetics

Diabetic nephropathy (DN) is a common and serious clinical complication of diabetes and presently there are no effective ways to prevent its occurrence and progression. Recent studies show that pentoxifylline (PTX) can improve renal hemodynamics, reduce urinary protein excretion, and alleviate or delay renal failure in DN patients. In this study, we focused on the anti-oxidative stress effect of PTX on alleviating renal damages of DN using rat models. DN rats were established with injection of streptozotocin. Blood glucose, urinary protein excretion, serum cystatin C, renal biopsy, superoxide dismutase (SOD) and malondialdehyde (MDA) in serum and renal homogenate and renal nitrotyrosine levels were analyzed before and 12 weeks after the treatment of PTX. Before treatment, all the DN rats had elevated blood glucose, increased urinary protein excretion and elevated serum cystatin C. Morphologically, DN rats exhibited renal tissue damages, including swelling and fusions of foot processes of podocytes under electron microscope. Masson staining revealed blue collagen deposition in glomeruli and renal interstitium. With treatment of PTX, symptoms and renal pathological changes of DN rats were alleviated. Furthermore, the MDA levels were increased and the SOD levels were decreased in the serum and kidneys of DN rats, and these changes were reversed by PTX. The expression of nitrotyrosine was up-regulated in DN rat model and down-regulated by PTX, indicating that PTX was able to inhibit oxidative reactions in DN rats. PTX could alleviate renal damage in DN, which may be attributable to its anti-oxidative stress activity.
Animals ; Biomarkers ; analysis ; Diabetes Mellitus, Experimental ; drug therapy ; pathology ; Diabetic Nephropathies ; drug therapy ; metabolism ; pathology ; Gene Expression Regulation ; drug effects ; Kidney ; metabolism ; pathology ; Malondialdehyde ; blood ; Oxidative Stress ; drug effects ; Pentoxifylline ; administration & dosage ; pharmacology ; Rats ; Streptozocin ; Superoxide Dismutase ; metabolism ; Tyrosine ; analogs & derivatives ; metabolism

OBJECTIVETo investigate the presence of p53 gene deletion in Xinjiang patients with chronic lymphocytic leukemia and its clinical significance.

METHODSInterphase fluorescence in situ hybridization (FISH) was used to detect the p53 gene deletion in 77 patients with CLL. Presence of the deletion and its association with clinical and laboratory features as well as prognostic factors were analyzed. Kaplan-Meier method was used to calculate survivals, and the results were compared using a Log-rank test.

RESULTSp53 gene deletion was found in 10 (12.9%) of the patients but none from the control group (P<0.05). The deletion was found in 12.5% (4/32) of ethnic Hans and 13.3% (6/45) of ethnic Uyghurs (P>0.05). No significant different distribution of p53 gene deletion was found in regard to sex, age, ethnicity, peripheral blood cell count (except for Hb) or the levels of lactate dehydrogenase, β2-micro globulin and CD38 (P>0.05). The deletion rate was higher in the group with high expression of ZAP-70 and patients with advanced stage disease than that in the group of low expression and early-stage CLL (P<0.05). Among 20 patients who received fludarabine therapy, the overall remission rate for those with p53 gene deletion (20%) was lower than those without (75%) (P<0.05). With a median follow-up time of 39.0 (8.0-136.0) months, 11 cases had died (14.3%), among them, 7 cases died from CLL and related complications, and all of them were founded p53 gene deletion. In patients with p53 gene deletion, the progression-free survival (18 months) was shorter than those without the deletion (55 months) (P<0.05).

CONCLUSIONThe p53 gene deletion has been found in more than 10% of patients with CLL, and the deletion rate did not significantly differ between ethnic Han and Uyghur patients. The deletion is associated with advanced stage of the disease. High-level ZAP-70 expression and the presence of p53 deletion are associated with shorter survival and poor response to fludarabine containing therapy. Therefore, drugs affecting the p53 signaling pathway should be avoided.

Adult ; Aged ; Aged, 80 and over ; Antineoplastic Agents ; therapeutic use ; Asian Continental Ancestry Group ; ethnology ; genetics ; Female ; Gene Deletion ; Humans ; In Situ Hybridization, Fluorescence ; Leukemia, Lymphocytic, Chronic, B-Cell ; diagnosis ; drug therapy ; ethnology ; genetics ; Male ; Middle Aged ; Prognosis ; Tumor Suppressor Protein p53 ; genetics ; Vidarabine ; analogs & derivatives ; therapeutic use ; ZAP-70 Protein-Tyrosine Kinase ; genetics

Adult ; Antineoplastic Combined Chemotherapy Protocols ; therapeutic use ; Cytarabine ; therapeutic use ; Female ; Follow-Up Studies ; Granulocyte Colony-Stimulating Factor ; therapeutic use ; Hematopoietic Stem Cell Transplantation ; Humans ; Induction Chemotherapy ; Leukemia, Myeloid, Acute ; drug therapy ; genetics ; therapy ; Male ; Middle Aged ; Transplantation Conditioning ; Transplantation, Autologous ; Treatment Outcome ; Vidarabine ; analogs & derivatives ; therapeutic use ; fms-Like Tyrosine Kinase 3 ; genetics