Cyclodipeptide (CDP) composed of two amino acids is the simplest cyclic peptide. These two amino acids form a typical diketopiperazine (DKP) ring by linking each other with peptide bonds. This characteristic stable ring skeleton is the foundation of CDP to display extensive and excellent bioactivities, which is beneficial for CDPs' pharmaceutical research and development. The natural CDP products are well isolated from actinomycetes. These bacteria can synthesize DKP backbones with nonribosomal peptide synthetase (NRPS) or cyclodipeptide synthase (CDPS). Moreover, actinomycetes could produce a variety of CDPs through different enzymatic modification. The presence of these abundant and diversified catalysis indicates that actinomycetes are promising microbial resource for exploring CDPs. This review summarized the pathways for DKP backbones biosynthesis and their post-modification mechanism in actinomycetes. The aim of this review was to accelerate the genome mining of CDPs and their isolation, purification and structure identification, and to facilitate revealing the biosynthesis mechanism of novel CDPs as well as their synthetic biology design.
Actinobacteria/metabolism* ; Actinomyces/metabolism* ; Biological Products/metabolism* ; Bacteria/metabolism* ; Diketopiperazines/metabolism* ; Amino Acids

PURPOSE: Dexrazoxane has been used as an effective cardioprotector against anthracycline cardiotoxicity. This study intended to analyze cardioprotective efficacy and secondary malignancy development, and elucidate risk factors for secondary malignancies in dexrazoxane-treated pediatric patients. MATERIALS AND METHODS: Data was collected from 15 hospitals in Korea. Patients who received any anthracyclines, and completed treatment without stem cell transplantation were included. For efficacy evaluation, the incidence of cardiac events and cardiac event-free survival rates were compared. Data about risk factors of secondary malignancies were collected. RESULTS: Data of total 1,453 cases were analyzed; dexrazoxane with every anthracyclines group (D group, 1,035 patients) and no dexrazoxane group (non-D group, 418 patients). Incidence of the reported cardiac events was not statistically different between two groups; however, the cardiac event-free survival rate of patients with more than 400 mg/m2 of anthracyclines was significantly higher in D group (91.2% vs. 80.1%, p=0.04). The 6-year cumulative incidence of secondary malignancy was not different between both groups after considering follow-up duration difference (non-D, 0.52%±0.37%; D, 0.60%±0.28%; p=0.55). The most influential risk factor for secondary malignancy was the duration of anthracycline administration according to multivariate analysis. CONCLUSION: Dexrazoxane had an efficacy in lowering cardiac event-free survival rates in patients with higher cumulative anthracyclines. As a result of multivariate analysis for assessing risk factors of secondary malignancy, the occurrence of secondary malignancy was not related to dexrazoxane administration.
Anthracyclines ; Cardiotoxicity ; Dexrazoxane ; Disease-Free Survival ; Follow-Up Studies ; Humans ; Incidence ; Korea ; Multivariate Analysis ; Neoplasms, Second Primary ; Risk Factors* ; Stem Cell Transplantation

One new sorbicillin derivative, 2-deoxy-sohirnone C (1), one new diketopiperazine alkaloid, 5S-hydroxynorvaline-S-Ile (2), and two naturally occurring diketopiperazines, 3S-hydroxylcyclo(S-Pro-S-Phe) (3) and cyclo(S-Phe-S-Gln) (4), together with three known compounds were isolated from the Chinese mangrove endophytic fungus Penicillium sp. GD6. Their structures were determined on the basis of extensive spectroscopic analyses and by comparison with literature data. The absolute configuration of 3-hydroxyl moiety in 3 was determined by Mosher's method, while the absolute stereochemistry of 2 and 4 was established by comparison with the CD spectra of natural and synthesized diketopiperazines. Compound 1 showed moderate antibacterial activity against Methicillin-resistant Staphylococcus aureus with a MIC value of 80 μg·mL.
Alkaloids ; chemistry ; isolation & purification ; Anti-Bacterial Agents ; chemistry ; isolation & purification ; pharmacology ; China ; Circular Dichroism ; Diketopiperazines ; chemistry ; isolation & purification ; Methicillin-Resistant Staphylococcus aureus ; drug effects ; Microbial Sensitivity Tests ; Molecular Structure ; Nuclear Magnetic Resonance, Biomolecular ; Penicillium ; chemistry ; Resorcinols ; chemistry ; isolation & purification ; pharmacology ; Rhizophoraceae ; microbiology ; Wetlands

PURPOSE: We intended to determine whether dexrazoxane (DZR) is cardioprotective during administration of adjuvant anthracycline-based chemotherapy followed by a 1-year trastuzumab treatment. METHODS: The medical records of 228 patients who underwent surgical resection and received adjuvant chemotherapy with trastuzumab for human epidermal growth factor receptor type 2 (HER2)-positive breast cancer between January 2010 and December 2014 were reviewed. Approximately 25% of patients received DZR prior to each administration of doxorubicin during doxorubicin with cyclophosphamide (AC) chemotherapy. DZR was not administered during the 1-year trastuzumab maintenance period. Rates of cardiac events (reduction in left ventricular ejection fraction [LVEF] by 10% or more; reduction in absolute LVEF to <45%) and cardiac event-free duration (CFD) were examined. The trastuzumab interruption rate was also assessed. RESULTS: Twelve percent of patients experienced a cardiac event. Repeated-measures analysis of variance for ejection fraction revealed a significant main effect of time, and a significant group (DZR)×time interaction. The group treated with adjuvant chemotherapy and DZR experienced significantly lower frequencies of cardiac events than the adjuvant chemotherapy only group. In multivariate analysis, DZR administration was associated with significantly fewer cardiac events. Moreover, DZR administration was an independent good prognostic factor for CFD. Only one patient (2.3%) experienced early interruption of trastuzumab in the adjuvant chemotherapy with DZR group due to cardiac toxicity, whereas 10 patients (7.6%) experienced a trastuzumab stop event in the adjuvant chemotherapy only group. CONCLUSION: DZR is cardioprotective in HER2-positive breast cancer patients who received adjuvant chemotherapy with trastuzumab. A large cohort randomized trial is needed to determine if DZR has an effect on trastuzumab interruption and completion of 12-month trastuzumab. Because cardiac toxicity has a significant negative effect on trastuzumab maintenance and quality of life, DZR administration could be considered concomitantly with anthracycline-based adjuvant chemotherapy with trastuzumab.
Breast Neoplasms* ; Breast* ; Cardiotoxicity ; Chemotherapy, Adjuvant* ; Cohort Studies ; Cyclophosphamide ; Dexrazoxane* ; Doxorubicin ; Drug Therapy ; Humans ; Medical Records ; Multivariate Analysis ; Quality of Life ; Receptor, Epidermal Growth Factor ; Stroke Volume ; Trastuzumab*

OBJECTIVETo evaluate whether ursolic acid can inhibit breast cancer resistance protein (BCRP)-mediated transport of rosuvastatin in vivo and in vitro.

METHODSFirstly, we explored the pharmacokinetics of 5-fluorouracil (5-FU, a substrate of BCRP) in rats in the presence or absence of ursolic acid. Secondly, we studied the pharmacokinetics of rosuvastatin in rats in the presence or absence of ursolic acid or Ko143 (inhibitor of BCRP). Finially, the concentration-dependent transport of rosuvastatin and the inhibitory effects of ursolic acid and Ko143 were examined in Madin-Darby Canine Kidney (MDCK) 2-BCRP421CC (wild type) cells and MDCK2-BCRP421AA (mutant type) cells.

RESULTSAs a result, significant changes in pharmacokinetics parameters of 5-FU were observed in rats following pretreatment with ursolic acid. Both ursolic acid and Ko143 could significantly affect the pharmacokinetics of rosuvastatin. The rosuvastatin transport in the BCRP overexpressing system was increased in a concentration-dependent manner. However, there was no statistical difference in BCRP-mediated transport of rosuvastatin betweent the wild type cells and mutant cells. The same as Ko143, ursolic acid inhibited BCRP-mediated transport of rosuvastatin in vitro.

CONCLUSIONUrsolic acid appears to be a potent modulator of BCRP that affects the pharmacokinetic of rosuvastatin in vivo and inhibits the transport of rosuvastatin in vitro.

ATP Binding Cassette Transporter, Sub-Family G, Member 2 ; ATP-Binding Cassette Transporters ; physiology ; Adenosine ; analogs & derivatives ; pharmacology ; Animals ; Biological Transport ; drug effects ; Diketopiperazines ; Heterocyclic Compounds, 4 or More Rings ; Hydroxymethylglutaryl-CoA Reductase Inhibitors ; pharmacokinetics ; Rats ; Rats, Sprague-Dawley ; Rosuvastatin Calcium ; pharmacokinetics ; Triterpenes ; pharmacology

In this study, it is to compare the effectiveness of prevention against and treatment of doxorubicin (DOX) induced cardiotoxicity by dexrazoxane and schisandrin B (Sch B) in rats. Sprague-Dawley (SD) rats were randomly divided into the following 6 groups: normal saline group, DOX group, DOX+DEX group, DOX+Sch B (80 mg x kg(-1)) group, DOX+Sch B (40 mg x kg(-1)) group and DOX+Sch B (20 mg x kg(-1)) group. The results showed that Sch B could combat the increase of myocardial enzymes in peripheral blood, decrease of the enzyme activity of myocardial tissue antioxidant enzymes and disorders of systolic and diastolic function of heart in rats intravenously injected with doxorubicin (15 mg x kg(-1)). Sch B was better than DEX in protecting rat against DOX-induced the symptoms. Sch B could protect rat against DOX-induced acute cardiomyopathy and has clinical potential applications.
Animals ; Antibiotics, Antineoplastic ; adverse effects ; Antioxidants ; metabolism ; Cardiomyopathies ; chemically induced ; drug therapy ; Cardiotoxicity ; drug therapy ; Cyclooctanes ; therapeutic use ; Dexrazoxane ; therapeutic use ; Doxorubicin ; adverse effects ; Heart ; physiopathology ; Lignans ; therapeutic use ; Myocardium ; enzymology ; Polycyclic Compounds ; therapeutic use ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo evaluate the cardioprotective effects of dexrazoxane (DEX) on breast cancer patients who received anthracycline-containing chemotherapy.

METHODSA total of 122 breast cancer patients after operation were randomly divided into two groups: The experimental group of 61 cases treated with EPI plus DEX (DEX:EPI = 10:1) as adjuvant chemotherapy regimen, and the control group of 61 cases treated with EPI but without DEX. All patients received four cycles of adjuvant chemotherapy and their changes of specific cardiac functional status and hematology status before and after chemotherapy, as well as non-cardiac toxicity were observed and analyzed.

RESULTSBrain natriuretic peptide (BNP) before chemotherapy and after four cycles of chemotherapy in the control group was (106.78 ± 4.52)×10(-6) µg/ml and (187.19 ± 8.71)×10(-6) µg/ml, respectively, with a significant difference between them (P < 0.05). It in the experimental group was (102.34 ± 8.76)×10(-6) µg/ml and (105.29 ± 7.21)×10(-6) µg/ml, respectively, without a significant difference (P > 0.05). Cardiac troponin T (cTnT) before chemotherapy and after four cycles of chemotherapy in the control group was (12.55 ± 2.73)×10(-3) µg/ml and ( 31.05 ± 7.10 )×10(-3) µg/ml, respectively, with a significant difference between them (P < 0.05). It in the experimental group was (12.70 ± 2.15)×10(-3) µg/ml and (13.65 ± 7.82)×10(-3) µg/ml, respectively, without a significant difference (P > 0.05). The hart rate (HR) before chemotherapy and after four cycles of chemotherapy in the control group, was 75.32 ± 7.14 bpm and 89.60 ± 9.21 bpm, respectively, with a significant difference (P < 0.05). It in the experimental group was 78.60 ± 6.29 bpm and 83.10 ± 7.56 bpm, respectively, without a significant difference (P > 0.05). The left ventricular ejection fraction (LVEF) before chemotherapy and after four cycles of chemotherapy in the control group was (65.23 ± 7.82)% and (55.21 ± 7.23)%, respectively, with a significant difference between them (P < 0.05). It in the experimental group was (64.12 ± 6.25)% and (59.6 ± 4.72)%, respectively, without a significant difference (P > 0.05). The absolute neutrophil count before chemotherapy and after four cycles of chemotherapy in the control group was (3.95 ± 1.36)×10(9)/L and (3.50 ± 1.52)×10(9)/L, respectively, without a significant difference (P > 0.05). It in the experimental group, was (4.96 ± 1.41)×10(9)/L and (3.10 ± 1.26)×10(9)/L, respectively, with a significant difference (P < 0.05). The incidence of grade I-IV bone marrow suppression in the experimental group was 21.3%, 16.4%, 24.6%, and 4.9%, respectively. It in the control group was 16.4%, 11.5%, 9.8%, and 5.5%, respectively, with a significant difference (P < 0.05).

CONCLUSIONSCardiac toxicity after anthracycline treatment in breast cancer patients may be significantly reduced by DEX, without increase of non-cardiac and and non-hematologic toxicity. DEX combined with anthracycline increases the risk of bone marrow suppression, therefore, peripheral blood picture should be monitored or routine bone marrow support may be needed.

Adolescent ; Adult ; Aged ; Antibiotics, Antineoplastic ; adverse effects ; therapeutic use ; Bone Marrow ; drug effects ; Breast Neoplasms ; drug therapy ; metabolism ; pathology ; physiopathology ; surgery ; Cardiovascular Agents ; adverse effects ; therapeutic use ; Chemotherapy, Adjuvant ; Epirubicin ; adverse effects ; therapeutic use ; Female ; Follow-Up Studies ; Heart Rate ; drug effects ; Humans ; Leukocyte Count ; Middle Aged ; Natriuretic Peptide, Brain ; metabolism ; Neutrophils ; cytology ; Razoxane ; adverse effects ; therapeutic use ; Stroke Volume ; drug effects ; Young Adult

Aspergillus fumigatus, a type of endophytic fungi from Erthrophleum fordii, was fermented with GPY culture medium. Fermented liquid and mycelium were extracted from fermented products after freezing and thawing treatment. After alcohol extraction, mycelium was extracted with ethyl acetate and n-butyl alcohol, respectively. According to the results of cytotoxity of tumor cells, ethyl acetate extracts were studied for their chemical constituents. Five diketopiperazine compounds were separated and purified with silica gel, MCI and Sephadex LH-20 column chromatography, reversed-phase chromatographic column and preparative HPLC, their structures were identified as cyclo- (R-Pro-R-Phe) (1), cyclo- (trans-4-OH-D-Pro-D-Phe) (2), cyclo- (R-Tyr-S-Ile) (3), cyclo-(R-Phe-S-Ile) (4), and cyclo-(R-Val-S-Tyr) (5) by using spectral methods.
Aspergillus fumigatus ; chemistry ; growth & development ; metabolism ; Cell Line, Tumor ; Diketopiperazines ; chemistry ; isolation & purification ; metabolism ; pharmacology ; Endophytes ; chemistry ; growth & development ; metabolism ; Fabaceae ; microbiology ; Humans ; Mycelium ; chemistry ; growth & development ; metabolism

S1-M1-80 cells, derived from human colon carcinoma S1 cells, are mitoxantrone-selected ABCG2-overexpressing cells and are widely used in in vitro studies of multidrug resistance(MDR). In this study, S1-M1-80 cell xenografts were established to investigate whether the MDR phenotype and cell biological properties were maintained in vivo. Our results showed that the proliferation, cell cycle, and ABCG2 expression level in S1-M1-80 cells were similar to those in cells isolated from S1-M1-80 cell xenografts (named xS1-M1-80 cells). Consistently, xS1-M1-80 cells exhibited high levels of resistance to ABCG2 substrates such as mitoxantrone and topotecan, but remained sensitive to the non-ABCG2 substrate cisplatin. Furthermore, the specific ABCG2 inhibitor Ko143 potently sensitized xS1-M1-80 cells to mitoxantrone and topotecan. These results suggest that S1-M1-80 cell xenografts in nude mice retain their original cytological characteristics at 9 weeks. Thus, this model could serve as a good system for further investigation of ABCG2-mediated MDR.
ATP Binding Cassette Transporter, Sub-Family G, Member 2 ; ATP-Binding Cassette Transporters ; antagonists & inhibitors ; metabolism ; Adenosine ; analogs & derivatives ; pharmacology ; Animals ; Antineoplastic Agents ; pharmacology ; Cell Cycle ; Cell Line, Tumor ; Cell Proliferation ; Cell Survival ; drug effects ; Cisplatin ; pharmacology ; Colonic Neoplasms ; metabolism ; pathology ; Diketopiperazines ; Doxorubicin ; metabolism ; Drug Resistance, Multiple ; Drug Resistance, Neoplasm ; Female ; Heterocyclic Compounds, 4 or More Rings ; Humans ; Inhibitory Concentration 50 ; KB Cells ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Mitoxantrone ; pharmacology ; Neoplasm Proteins ; antagonists & inhibitors ; metabolism ; Neoplasm Transplantation ; Rhodamine 123 ; metabolism ; Topotecan ; pharmacology

This study attempted to assess the incidence and outcome of anthracycline cardiotoxicity and the role of dexrazoxane as a cardioprotectant in childhood solid tumors. The dexrazoxane group included 47 patients and the control group of historical cohort included 42. Dexrazoxane was given in the 10:1 ratio to doxorubicin. Fractional shortening and systolic and diastolic left ventricular diameters were used to assess the cardiac function. The median follow-ups were 54 months in the dexrazoxane group and 86 months in the control group. The mean cumulative doses of doxorubicin were 280.8+/-83.4 mg/m2 in the dexrazoxane group and 266.1+/-75.0 mg/m2 in the control group. The dexrazoxane group experienced significantly fewer cardiac events (27.7% vs. 52.4%) and less severe congestive heart failure (6.4% vs. 14.3%) than the control group. Thirteen cardiotoxicities including one cardiac death and 2 congestive heart failures occurred in the dexrazoxane group, and 22 cardiotoxicities including 2 cardiac deaths and 4 congestive heart failures, in the control group. Five year cardiac event free survival rates were 69.2% in the dexrazoxane group and 45.8% in the control group (P=0.04). Dexrazoxane reduces the incidence and severity of early and late anthracycline cardiotoxicity in childhood solid tumors.
Adolescent ; Antibiotics, Antineoplastic/*adverse effects ; Cardiomyopathies/chemically induced/prevention & control ; Cardiovascular Agents/*therapeutic use ; Child ; Child, Preschool ; Cohort Studies ; Disease-Free Survival ; Doxorubicin/*adverse effects ; Echocardiography ; Female ; Follow-Up Studies ; Heart Failure/chemically induced/prevention & control ; Humans ; Infant ; Male ; Neoplasms/*drug therapy/mortality ; Razoxane/*therapeutic use ; Ventricular Function, Left/physiology