In the current study, the combined anti-tumor efficacy of bioactive hydroxyapatite nano- particles (HA-NPs) loaded with altretamine (ALT) was evaluated. The well-known fact that HA has great biological compatibility was confirmed through the findings of the hemolytic experiments and a maximum IC50 value seen in the MTT testing. The preparation of HA-NPs was performed using the chemical precipitation process. An in vitro release investigation was conducted, and the results demonstrated the sustained drug release of the altretamine-loaded hydroxyapatite nanoparticles (ALT-HA-NPs). Studies using the JURKAT E6.1 cell lines MTT assay, and cell uptake, as well as in vivo pharmacokinetic tests using Wistar rats demonstrated that the ALT-HA-NPs were easily absorbed by the cells. A putative synergism between the action of the Ca2+ ions and the anticancer drug obtained from the carrier was indicated by the fact that the ALT-HA-NPs displayed cytotoxicity comparable to the free ALT at 1/10th of the ALT concentration. It has been suggested that a rise in intracellular Ca2+ ions causes cells to undergo apoptosis. Ehrlich's ascites model in Balb/c mice showed comparable synergistic efficacy in a tumor regression trial. While the ALT-HA-NPs were able to shrink the tumor size by six times, the free ALT was only able to reduce the tumor volume by half.

The dimethylamino functionality has significant importance in industrially relevant molecules and methodologies to install these efficiently are highly desirable. We report herein a highly efficient, room-temperature dimethylamination of chloroheteroarenes performed via the in-situ generation of dimethylamine using N,N-dimethylformamide (DMF) as precursor wiith a large substrate scope that includes various heteroarenes, purines as well as commercially relevant drugs such as altretamine, ampyzine and puromycin precursor.

Insights into drug-DNA interactions have importance in medicinal chemistry as it has a major role in the evolution of new therapeutic drugs. Therefore, binding studies of small molecules with DNA are of significant interest. Spectroscopy, coupled with measurements of viscosity and molecular docking studies were employed to obtain mechanistic insights into the binding of altretamine with calf thymus DNA (CT-DNA). The UV-visible spectroscopic measurements study confirmed altretamine-CT-DNA complex formation with affinity constant ([15.68 ± 0.04] × 103 M-1), a value associated with groove binding phenomenon. The associated thermodynamic signatures suggest enthalpically driven interactions. The values of standard molar free energy change (ΔGmo) -(23.93 ± 0.23) kJ mol-1, enthalpy change (ΔvHHmo) -(50.84 ± 0.19) kJ mol-1 and entropy change (ΔSmo) -(90.29 ± 0.12) JK-1 mol-1 indicate the binding is thermodynamically favorable and an important role of the hydrogen bonds and Van der Waals interactions in the binding of altretamine with CT-DNA. Circular dichroism spectroscopy indicated insignificant conformational changes in the DNA backbone upon interaction with altretamine suggesting no distortion and/or unstacking of the base pairs in the DNA helix. UV-melting study suggested that the thermal stability of the DNA backbone is not affected by the binding of the drug. Competitive displacement assays with ethidium bromide, Hoechst-33258 and DAPI established the binding of altretamine with CT-DNA in the minor groove. The mode of binding was further confirmed by viscosity and molecular docking studies. Molecular docking further ascertained binding of altretamine in the minor groove of the CT-DNA, preferably with the A-T rich sequences.

Ferroptosis, a form of programmed cell death, is mediated primarily by lipid peroxidation via a unique iron-dependent process. The mechanisms of ferroptosis involve the metabolisms of amino acids, irons, and lipids, and the regulation of antioxidant systems. Evidence supports the roles of ferroptosis in cancer, while metabolic reprogramming (a hallmark of cancer) renders tumor cells highly vulnerable to ferroptosis and thus provides a rationale for ferroptosis-targeted therapy for cancer.

The present work utilizes density functional theory (DFT) calculations to study the influence of cation-π interactions on the electronic properties of the complexes formed by Altretamine [2,4,6-tris(dimethylamino)-1,3,5-triazine], an anticancer drug, with mono- and divalent (Li+, Na+, K+, Be2+, Mg2+ and Ca2+) metal cations. The structures were optimized with the M06-2X method and the 6-311++G(d,p) basis set in the gas phase and in solution. The theory of `Atoms in Molecules' (AIM) was applied to study the nature of the interactions by calculating the electron density ρ(r) and its Laplacian at the bond critical points. The charge-transfer process during complexation was evaluated using natural bond orbital (NBO) analysis. The results of DFT calculations demonstrate that the strongest/weakest interactions belong to Be2+/K+ complexes. There are good correlations between the achieved densities and the amounts of charge transfer with the interaction energies. Finally, the stability and reactivity of the cation-π interactions can be determined by quantum chemical computation based on the molecular orbital (MO) theory.

The Zi goose is native to North-east China and is noted for its high egg production. Alpha enolase (ENO1) is a glycolytic enzyme which functions as a plasminogen receptor in follicular granulosa cells (FGCs), with several studies showing that FGCs can support follicular development. By transfecting the ENO1 interfering plasmid (shRNA) into FGCs, ENO1 expression in these cells was downregulated, suggesting the successful knock-down of ENO1 in these cells. In this knock-down model, we detected 13 metabolites from FGCs using LC/MS. When compared with the non-coding shRNA (NC) group, the lower level metabolites were (R)-(+)-citronellic acid, altretamine, 3-hydroxycaproic acid, heptadecanoic acid, cholecalciferol vitamin D3, indole, benzoic acid, capric acid, caffeic acid, azelaic acid, 3,4-dihydroxyhydrocinnamic acid and cholic acid, while oleic acid was detected at high levels. To further examine the results of metabolomics, six key metabolites were verified by gas chromatography-mass spectrometry (GC-MS). We found that vitamin D3, indole, benzoic acid, capric acid and cholic acid were significantly downregulated in the shRNA group, while oleic acid was significantly upregulated. This observation was consistent with the metabolomics data. Through these studies, we found that decreased ENO1 levels altered certain metabolite levels in FGCs.

Binding of anticancer drug altretamine with bovine serum albumin (BSA) and its inhibitory effect on fibrillation of the protein has been studied by using a combination of spectroscopic and calorimetric methods. Altretamine is observed to bind with BSA with a moderate binding affinity of the order of 105, which is weakly temperature dependent. Circular dichroism, fluorescence spectroscopic and dynamic light scattering methods have been employed to monitor the conformational change in the protein. Time correlated single photon counting measurements have confirmed ground state complexation of the drug with the protein. Docking studies have led to identification of binding sites on BSA at site III in domain IB. Thioflavin T (ThT) fluorescence emission has been used as a tool to monitor the formation of fibrils/aggregates in BSA. It is observed that anticancer drug altretamine can also act as an inhibitor of fibrillation in BSA and hence can be useful in the treatment of neuro-degenerative diseases. Differential scanning calorimetry has been employed to study the thermal transitions of BSA at different stages of the fibrillation process with and without altretamine to obtain insights into the extent of stabilisation provided by the drug to the protein in native, nucleation/elongation and matured state in the fibrillation process.

Microbes are nature's chemists, capable of producing and metabolizing a diverse array of compounds. In the human gut, microbial biochemistry can be beneficial, for example vitamin production and complex carbohydrate breakdown; or detrimental, such as the reactivation of an inactive drug metabolite leading to patient toxicity. Identifying clinically relevant microbiome metabolism requires linking microbial biochemistry and ecology with patient outcomes. Here we present MicrobeFDT, a resource which clusters chemically similar drug and food compounds and links these compounds to microbial enzymes and known toxicities. We demonstrate that compound structural similarity can serve as a proxy for toxicity, enzyme sharing, and coarse-grained functional similarity. MicrobeFDT allows users to flexibly interrogate microbial metabolism, compounds of interest, and toxicity profiles to generate novel hypotheses of microbe-diet-drug-phenotype interactions that influence patient outcomes. We validate one such hypothesis experimentally, using MicrobeFDT to reveal unrecognized gut microbiome metabolism of the ovarian cancer drug altretamine.

Altretamine is a synthetic drug approved for treatment of ovarian cancer. The only drawback with its formulation is poor aqueous solubility and low oral bioavailability. In the present work an attempt has been made to prepare inclusion complex of altretamine with epichlorohydrin beta cyclodextrin. The complexes were prepared by kneading, co-evaporation and freeze-drying method and were confirmed by FTIR, XRD, DSC, drug content and dissolution study. Kneaded complex possess maximum solubilizing efficiency of 82.63 in 25mM Epi-β-CD solution. SLNs of pure altretamine and ALT complexed with Epi-β-CD were prepared by modified emulsification-ultrasonication method. The particle size and zeta potential was found to be 151.5nm and -21.3mV. The drug release pattern of SLNs was bi-phasic in nature; with an initial burst release followed by sustained drug release. Pharmacokinetic study showed that the average Cmax was found to be 0.94μg/ml, which was 2.47 times higher as compared to the pure drug. The AUCt for SLNs was 150minμgh/ml and 54minμgh/ml for pure ALT suspension which proved that the SLNs exhibited greater absorption compared to the pure drug. Thus, smaller particle size, higher entrapment efficiency and enhanced aqueous solubility led to improvement in oral bioavailability of ALT.

Altretamine is an orally administered alkylating agent, formerly known as hexamethylmelamine, which is currently used as a secondary therapy for advanced ovarian carcinoma. Altretamine therapy has been associated with low rates of serum enzyme elevations during therapy and with rare instances of acute, clinically apparent injury.

Genome-wide identification of the mechanism of action (MoA) of small-molecule compounds characterizing their targets, effectors, and activity modulators represents a highly relevant yet elusive goal, with critical implications for assessment of compound efficacy and toxicity. Current approaches are labor intensive and mostly limited to elucidating high-affinity binding target proteins. We introduce a regulatory network-based approach that elucidates genome-wide MoA proteins based on the assessment of the global dysregulation of their molecular interactions following compound perturbation. Analysis of cellular perturbation profiles identified established MoA proteins for 70% of the tested compounds and elucidated novel proteins that were experimentally validated. Finally, unknown-MoA compound analysis revealed altretamine, an anticancer drug, as an inhibitor of glutathione peroxidase 4 lipid repair activity, which was experimentally confirmed, thus revealing unexpected similarity to the activity of sulfasalazine. This suggests that regulatory network analysis can provide valuable mechanistic insight into the elucidation of small-molecule MoA and compound similarity.

The objective of the present study was to prepare solid lipid nanoparticles (SLNs) of altretamine (ALT) by the hot homogenization and ultrasonication method. The study was conducted using the Box-Behnken design (BBD), with a 3(3) design and a total of 17 experimental runs, performed in combination with response surface methodology (RSM). The SLNs were evaluated for mean particle size, entrapment efficiency, and drug-loading. The optimized formulation, with a desirability factor of 0.92, was selected and characterized. In vitro release studies showed a biphasic release pattern from the SLNs for up to 24 h. The results of % EE (93.21 ± 1.5), %DL (1.15 ± 0.6), and mean diameter of (100.6 ± 2.1) nm, were very close to the predicted values.

Liposomes incorporating sodium deoxycholate (NaDC) were prepared by the method of reverse phase evaporation and used for drug delivery by the oral route. Hexamethylmelamine (HMM), an anti-tumor agent, was chosen as a model drug and encapsulated into liposomes incorporating NaDC (NaDC-Lip). Several properties of NaDC-Lip containing HMM (HMM NaDC-Lip), such as particle size, entrapment efficiency, pinacyanol chloride (PIN) spectral characteristics with various molar ratio of NaDC/PC, as well as the vesicle stability measurements with calcein were evaluated. In vivo, the area under the plasma concentration-time curve obtained from the pharmacokinetics study of HMM NaDC-Lip was found to be approximately 9.76- and 1.21-fold higher than that of HMM solution and HMM Lip, respectively, indicating that NaDC-Lip can be used as a potential carrier for oral drug administration.

The aim of this study was to assess the efficacy of consolidation therapy with hexamethylmelamine (HMM) in patients with advanced epithelial ovarian cancer (EOC). Patients treated at our hospital between January 1997 and November 2006 and in documented clinical complete response from advanced ovarian cancer following front-line platinum-based therapy were retrospectively analyzed. The patients treated with HMM were compared to the patients of matched counterpart without consolidation therapy. Of 102 patients enrolled, 49 were treated with HMM and 53 received no consolidation treatment. For patients with HMM and observed patients, the mean age were 54.6 and 55.6 yr; the distribution of stage was similar (P=0.977); the optimal surgery was performed in 36 (73.5%) and 44 (83%) (P=0.336); the recurrence rate were 27 (55.1%) and 33 (62.3%) (P=0.463); and the median progression-free survival were 38 months and 21 months for patients with HMM and observed patients (P=0.235). No treatment-related adverse events were reported during the follow-up period. Although this study failed to show the significant survival benefit of consolidation therapy with HMM in patients with advanced EOC, we consider that our study can contribute data to investigate the effectiveness of consolidation therapy in epithelial ovarian cancer.

A novel method for the cyclotrimerization of dimethylcyanamide to form hexamethylmelamine has been developed using an aluminium amide catalyst; detailed DFT modelling of the catalytic cycle supports a triple insertion, nucleophilic ring closure, deinsertion mechanism.

The manuscript by Armstrong et al. in this issue of The Oncologist, reviewing the toxicity and efficacy of full-dose topotecan delivered as second-line therapy in individuals with small cell lung cancer or ovarian cancer, will likely serve as both the most comprehensive and the final review of this active agent delivered at the U.S. Food and Drug Administration-approved dosage and schedule. The review represents large, relative lyhomogeneous patient populations with prior platinum exposure and convincingly describes topotecan as an agent with activity that is comparable with those of all other approved drugs in this setting and a well-defined and relatively circumscribed set of toxicities. While the activity of topotecan in small cell carcinoma provides individuals with the hope for further palliation at the time of tumor recurrence, as discussed by Dr. Markman in this issue, the best use of this agent in the management of recurrent ovarian cancer is far from clear because, in part, of a growing list of approved active agents, most notably liposomal doxorubicin, gemcitabine, and weekly paclitaxel; a return to platinum; or a host of other agents such as vinorelbine, altretamine, irinotecan, docetaxel, etoposide, and others. The most pressing need is to accept that palliative therapies are designed to palliate and improve symptoms, and to move away from end points of radiologic and marker response to a focus on "clinical benefit" and clinically more meaningful end points.

Ovarian cancer is increasingly recognized as a chronic disease whose treatment is often characterized by administration of multiple, sequential active agents, each of which may or may not be accompanied by a tumor response. Despite the large proportion of patients who relapse and undergo longer-term treatment, the question of optimal treatment duration has not been fully addressed to date. For patients who progress on therapy, the answer is straightforward: they are switched to another active agent, presumably having a different mechanism of action from previous therapies with, ideally, limited overlapping toxicities. However, for patients who remain in partial response or who have stable disease, the answer is less apparent and less clear. The majority of oncologists believe that treatment beyond 6 cycles of a given therapy does not provide any additional benefit to patients. There are some data to support that treatment strategy. However, with the advent of new, less toxic agents, treatment to progression should be further explored. Agents that are potentially well suited for extended treatment intervals may include such properties as absence of cumulative toxicity, non-cross-resistance, positive benefit on quality of life, and convenient schedule. A number of active agents in ovarian cancer (platinum, paclitaxel, topotecan, liposomal doxorubicin, docetaxel, gemcitabine, and etoposide) will be reviewed in the context of what is known about cumulative toxicity, potential adverse effects on patients' quality of life, and evidence addressing the potential benefits of longer-term treatment.

To investigate the best first-line chemotherapy regimen for the treatment of advanced epithelial ovarian cancer (AEOC), the efficacy of three chemotherapy regimens for treatment of the patients with AEOC in our hospital during Jan. 1992-Jan. 1999 was retrospectively analyzed. The therapeutic effects were compared with the supplement of Melphalan + Hexamethylme (PAM + HMM), cisplatin + adriamycin + cyclophosphamide or isofamide (PAC) or cisplatin + cyclophosphamide or isofamide (PC), Taxol + cisplatin (TP) combined chemotherapy after cytoreductive surgery. The results showed that the overall effective rate of TP was significantly higher than that of PAM + HMM (P < 0.05); The complete remission rate of TP was significantly higher than that of PAM + HMM and PAC or PC (all P < 0.05); The 2-year survival rate free of tumor of TP was obviously higher than that of PAM + HMM and PAC or PC (all P < 0.05). It was concluded that the therapeutic effect of TP regimen in the treatment of AEOC was better than PAM + HMM and PAC or PC and TP regimen could be recommended currently as the preferred first-line one for the treatment of AEOC.

For women with advanced ovarian cancer, rates of response to first-line chemotherapy are high but most patients have relapses and become candidates for further chemotherapy. Chemotherapy for recurrence can palliate symptoms, and there is some evidence that it can also improve survival in this clinical situation. Patients who relapse quickly after first-line therapy should not be given the same drugs as were used initially. However, for patients who have longer intervals from treatment to relapse, the rates of response to a rechallenge with platinum are clinically significant. Several cytotoxic drugs have shown activity in patients whose disease has relapsed after therapy with platinum and a taxane; these drugs include topotecan, etoposide, pegylated liposomal doxorubicin, epirubicin, gemcitabine, altretamine, oxali platin, and vinorelbine. Recurrent ovarian cancer is also an important setting in which to test investigational agents with promising activity, such as new platinum compounds, new taxanes, and other cytotoxic agents, as well as non-cytotoxic compounds with novel mechanisms of action.

Biodegradable poly(D,L-lactic acid) (PLA) microspheres containing hexamethylmelamine (HMM) were developed for potential use in chemoembolization and intraperitoneal implantation. The emulsion-solvent-evaporation/extraction method was used to prepare 15 formulations with different drug/polymer ratios, solvent compositions and emulsifer concentrations in the continuous aqueous phase. A central composite experimental design was used, with five levels of the three different factors. All formulations resulted in the formation of discrete matrix microspheres containing crystalline drug. The mean particle sizes of the microsphere formulations ranged from 62-348 microm and the effect of the independent variables on microsphere size was satisfactorily predicted using response surface methodology. For theoretical drug loads of 5-40%, efficiency of entrapment ranged from 75-107% and porosities of the microspheres were between 0-6.5%. The rate of drug release from the microspheres depended on drug loading and particle size. Microspheres with 22.5% or greater theoretical drug content released drug rapidly, with almost complete release occurring in 70 h or less. Formulations with drug loading of 5% and 9.57%, however, released drug very slowly, with less than 50% released in 40 days. Release kinetics of narrow sieve cuts of microspheres with high drug load (35.4%) followed square root of time profiles.