Interaction between environmental pollutants and cancer drug efficacy: Bisphenol A, Bisphenol A diglycidyl ether and Perfluorooctanoic acid reduce vincristine cytotoxicity in acute lymphoblastic leukemia cells.

Every day, we are exposed to many environmental pollutants that can enter our body through different routes and cause adverse effects on our health. Epidemiological studies suggest that these pollutants are responsible for approximately nine million deaths per year. Acute lymphoblastic leukemia (ALL) represents one of the major cancers affecting children, and although substantial progress has been made in its treatment, relapses are frequent after initial treatment and are now one of the leading causes of cancer-related death in pediatric patients. Currently, relatively little attention is paid to pollutant exposure during drug treatment and this is not taken into account for dose setting or regulatory purposes. In this work, we investigated how bisphenol A (BPA), its derivative bisphenol A diglycidyl ether (BADGE), and perfluorooctanoic acid (PFOA) alter vincristine treatment in ALL when administered before or together with the drug. We found that these three pollutants at nanomolar concentrations, lower than those established by current regulations, can reduce the cytotoxic effects of vincristine on ALL cells. Interestingly, we found that this is only achieved when exposure to pollutants occurs prior to administration of the chemotherapeutic drug. Moreover, we found that this effect could be mediated by activation of the PI3K/AKT pathway and stabilization of microtubules. This work strengthens the idea of starting to take into account exposure to pollutants to improve the efficacy of chemotherapy treatments.

Vincristine-doxorubicin co-loaded artificial low-density lipoproteins towards solid tumours.

To construct an artificial low-density lipoprotein (aLDL) that highly mimics low-density lipoprotein (LDL) in vivo, and deliver vincristine (VCR) - doxorubicin (DOX) simultaneously, the 100 nm and 35 nm DOX-VCR-aLDLs (DV-aLDLs) were constructed, then the physicochemical characteristics were evaluated. Through in vitro inverse gravity diffusion experiment, the tumour cake and sphere model experiment, draw a conclusion that the diffusion of 35 nm DV-aLDLs was stronger than 100 nm DV-aLDLs, and the tumour retention of 35 nm DV-aLDLs was better than the DV-solution. In addition, the three-dimension (3D) in vivo distribution imaging of aLDLs was performed on HepG-2 tumour-bearing nude mice, followed by the biodistribution and therapeutic efficacy on these xenograft models. Taking advantage of better diffusion capacity in tumour tissue, as well as the synergistic effect of VCR and DOX, the 35 nm DV-aLDL had the strongest efficacy and the lowest toxicity. High entrapment efficiency and stability, both active and passive targeting, making aLDL a potential carrier for tumour-targeted therapy at the same time.

Influence of Vincristine, Clinically Used in Cancer Therapy and Immune Thrombocytopenia, on the Function of Human Platelets.

Vincristine is a clinically used antimicrotubule drug for treating patients with lymphoma. Due to its property of increasing platelet counts, vincristine is also used to treat patients with immune thrombocytopenia. Moreover, antiplatelet agents were reported to be beneficial in thrombotic thrombocytopenic purpura (TTP). Therefore, we investigated the detailed mechanisms underlying the antiplatelet effect of vincristine. Our results revealed that vincristine inhibited platelet aggregation induced by collagen, but not by thrombin, arachidonic acid, and the thromboxane A2 analog U46619, suggesting that vincristine exerts higher inhibitory effects on collagen-mediated platelet aggregation. Vincristine also reduced collagen-mediated platelet granule release and calcium mobilization. In addition, vincristine inhibited glycoprotein VI (GPVI) signaling, including Syk, phospholipase Cγ2, protein kinase C, Akt, and mitogen-activated protein kinases. In addition, the in vitro PFA-100 assay revealed that vincristine did not prolong the closure time, and the in vivo study tail bleeding assay showed that vincristine did not prolong the tail bleeding time; both findings suggested that vincristine may not affect normal hemostasis. In conclusion, we demonstrated that vincristine exerts antiplatelet effects at least in part through the suppression of GPVI signaling. Moreover, this property of antiplatelet activity of vincristine may provide additional benefits in the treatment of TTP.

Daratumumab Immunopolymersome-Enabled Safe and CD38-Targeted Chemotherapy and Depletion of Multiple Myeloma.

Multiple myeloma (MM) is a second ranking hematological malignancy. Despite the fast advancement of new treatments such as bortezormib and daratumumab, MM patients remain incurable and tend to eventually become relapsed and drug-resistant. Development of novel therapies capable of depleting MM cells is strongly needed. Here, daratumumab immunopolymersomes carrying vincristine sulfate (Dar-IPs-VCR) are reported for safe and high-efficacy CD38-targeted chemotherapy and depletion of orthotopic MM in vivo. Dar-IPs-VCR made by postmodification via strain-promoted click reaction holds tailored antibody density (2.2, 4.4 to 8.7 Dar per IPs), superb stability, small size (43-49 nm), efficacious VCR loading, and glutathione-responsive VCR release. Dar4.4 -IPs-VCR induces exceptional anti-MM activity with an IC50 of 76 × 10-12 m to CD38-positive LP-1 MM cells, 12- and 20-fold enhancement over nontargeted Ps-VCR and free VCR controls, respectively. Intriguingly, mice bearing orthotopic LP-1-Luc MM following four cycles of i.v. administration of Dar4.4 -IPs-VCR at 0.25 mg VCR equiv. kg-1 reveal complete depletion of LP-1-Luc cells, superior survival rate to all controls, and no body weight loss. The bone and histological analyses indicate bare bone and organ damage. Dar-IPs-VCR appears as a safe and targeted treatment for CD38-overexpressed hematological malignancies.

Gastrodia elata Blume Polysaccharides Attenuate Vincristine-Evoked Neuropathic Pain through the Inhibition of Neuroinflammation.

Vincristine (Vin) is a well-known antitumor agent that frequently evokes neuropathic pain and decreases the quality of life of patients. Polysaccharides (GBP) extracted from Gastrodia elata Blume have been demonstrated to possess anti-inflammatory and neuroprotective effects in vivo; however, the effects of GBP on Vin-induced neuropathic pain remain unknown. The present study is aimed at exploring the alleviative potential of GBP against chemotherapy-evoked peripheral neuropathy to better understand and extend its pharmacological application. Vin was administered intraperitoneally to evoke neuropathic pain. GBP was orally administered for 21 days. The mechanical allodynia and thermal hyperalgesia were assessed using the Von Frey test and hot-plate test. Histopathological changes were assessed by hematoxylin and eosin staining. ELISA kits were used to measure the levels of inflammatory cytokines in the sciatic nerve, spinal cord, and dorsal root ganglion (DRG). qRT-PCR was employed to examine the expression of inflammatory cytokines and Sirtuin1 (SIRT1) in the sciatic nerve, spinal cord, and DRG. Our findings revealed that GBP treatment enhanced the paw withdrawal latency and paw withdrawal threshold and restored Vin-induced sciatic nerve damage in rats. GBP also attenuated the Vin-induced increase of proinflammatory cytokine levels, including IL-6, IL-8, TNF-α, IL-1ß, and NF-κB. On the molecular level, treatment with GBP downregulated the mRNA levels of IL-6, IL-8, TNF-α, and IL-1ß in the sciatic nerve, spinal cord, and DRG. Meanwhile, GBP increased SIRT1 activity and mRNA expression levels. Our data indicated that GBP exerted a potential protective effect against chemotherapy-induced neuropathic pain which might be mediated via the inhibition of neuroinflammation.

Rapid quantification of vincristine in mouse plasma using ESI-LC-MS/MS: Application to pharmacokinetic studies.

A simple, rapid, and sensitive LC-MS/MS method for determining concentrations of the anticancer alkaloid vincristine in micro volumes of mouse plasma was developed and validated in positive ion mode. Separation of vincristine and the internal standard [2H3]-vincristine was achieved on an Accucore aQ column with a gradient mobile phase delivered at a flow rate of 0.4 mL/min and a run time of 2.2 min. Calibration curves were linear (r2 > 0.99, n = 8) up to 250 ng/mL, with a lower limit of quantitation of 2.5 ng/mL. The matrix effect and extraction recovery for vincristine were ranging 108-110% and 88.4-107%, respectively. The intra-day and inter-day precision of quality controls tested at 3 different concentrations were always less than 15%, and accuracy ranged from 91.7 to 107%. The method was successfully applied to evaluate the pharmacokinetic profile of vincristine in wild-type and CYP3A-deficient mice in support of a project to provide mechanistic insight into drug-drug interactions and to identify sources of inter-individual pharmacokinetic variability associated with vincristine-induced peripheral neuropathy.

Rapid scale-up and production of active-loaded PEGylated liposomes.

Manufacturing of liposomal nanomedicines (e.g. Doxil®/Caelyx®) is a challenging and slow process based on multiple-vessel and batch processing techniques. As a result, the translation of these nanomedicines from bench to bedside has been limited. Microfluidic-based manufacturing offers the opportunity to address this issue, and de-risk the wider adoption of nanomedicines. Here we demonstrate the applicability of microfluidics for continuous manufacturing of PEGylated liposomes encapsulating ammonium sulfate (250 mM). Doxorubicin was subsequently active-loaded into these pre-formed liposomes. Critical process parameters and material considerations demonstrated to influence the liposomal product attributes included solvent selection and lipid concentration, flow rate ratio, and temperature and duration used for drug loading. However, the total flow rate did not affect the liposome product characteristics, allowing high production speeds to be adopted. The final liposomal product comprised of 80-100 nm vesicles (PDI < 0.2) encapsulating ≥ 90% doxorubicin, with matching release profiles to the innovator product and is stable for at least 6 months. Additionally, vincristine and acridine orange were active-loaded into these PEGylated liposomes (≥ 90% and ~100 nm in size) using the same process. These results demonstrate the ability to produce active-loaded PEGylated liposomes with high encapsulation efficiencies and particle sizes which support tumour targeting.

Biotechnological advancements in Catharanthus roseus (L.) G. Don.

Catharanthus roseus (L.) G. Don, also known as Madagascar periwinkle or Sadabahar, is a herbaceous plant belonging to the family Apocynaceae. Being a reservoir for more than 200 alkaloids, it reserves a place for itself in the list of important medicinal plants. Secondary metabolites are present in its leaves (e.g., vindoline, vinblastine, catharanthine, and vincristine) as well as basal stem and roots (e.g., ajmalicine, reserpine, serpentine, horhammericine, tabersonine, leurosine, catharanthine, lochnerine, and vindoline). Two of its alkaloids, vincristine and vinblastine (possessing anticancerous properties), are being used copiously in pharmaceutical industries. Till date, arrays of reports are available on in vitro biotechnological improvements of C. roseus. The present review article concentrates chiefly on various biotechnological advancements based on plant tissue culture techniques of the last three decades, for instance, regeneration via direct and indirect organogenesis, somatic embryogenesis, secondary metabolite production, synthetic seed production, clonal fidelity assessment, polyploidization, genetic transformation, and nanotechnology. It also portrays the importance of various factors influencing the success of in vitro biotechnological interventions in Catharanthus and further addresses several shortcomings that can be further explored to create a platform for upcoming innovative approaches. KEY POINTS: • C. roseus yields anticancerous vincristine and vinblastine used in pharma industry. •In vitro biotechnological interventions prompted major genetic advancements. • This review provides an insight on in vitro-based research achievements till date. • Key bottlenecks and prospective research methodologies have been identified herein.

Biomimetic drug delivery platforms based on mesenchymal stem cells impregnated with light-responsive submicron sized carriers.

Synthetic organic and inorganic carriers often have limitations associated with problematic targeting ability or non-optimized pharmacokinetics, and, therefore, they have restricted therapeutic potential. Natural drug carriers (e.g. mesenchymal stem cells, MSCs) are able to migrate towards the tumor site and penetrate cancerous cells. These biomimetic features make MSCs an attractive delivery platform that allows achieving maximal therapeutic efficiency with minimal toxic side effects. A combination of MSCs exhibiting a homing effect on tumors with stimuli-responsive nanostructured carriers is foreseen to have a huge impact in the field of personalized oncology. Here we develop for the first time a light-sensitive biomimetic delivery platform based on MSCs impregnated with submicron sized composite capsules containing an antitumor drug. This cell-based delivery system triggers the release of the drug upon near-infrared (NIR) laser irradiation due to gold nanorods (Au NRs) incorporated into the capsule wall. The NIR-triggered release of the antitumor drug such as vincristine leads to the effective mortality of tumor spheroids made of primary melanoma cells. Encapsulated vincristine delivered by MSCs into the tumor spheroids and deployed over the whole spheroid upon NIR exposure represents a promising therapy for the improved treatment of malignant neoplasms.

Multidrug resistant tumors-aimed theranostics on the basis of strong electrostatic attraction between resistant cells and nanomaterials.

Chemotherapy is one of the most common and effective ways for the clinical treatment of tumors, but tumor cells develop resistance toward drugs after a long period of chemotherapy. Interestingly, the gene expression of resistant cells usually generates increased sialic acid and raises the negative potential of the cell membranes, which is potentially useful to design novel theranostic models. In this work, we demonstrate multidrug resistant tumors-aimed theranostics by the virtue of the strong electrostatic attraction between resistant cells and nanomaterials. Human oral epithelial carcinoma vincristine-resistant tumor (KBV) and human oral epithelial carcinoma tumor (KB) were employed and compared as the tumor models. Polyethylene glycol-coated and Cu(ii) and vincristine codoped polyaniline nanoshuttles (VCR-PEG-CuPani NSs), which possessed multifunctions, positive charges, and blood circulation half-life of 6.26 ± 0.16 h, were employed as the nanomaterials for performing the tumor theranostics. Because of the stronger electrostatic attraction with KBV than that with KB, VCR-PEG-CuPani NSs showed higher enrichment of 8.05 ± 0.39% ID g-1 for KBV and a lower value of 6.02 ± 0.22% ID g-1 for KB. The higher accumulation of VCR-PEG-CuPani NSs in KBV tumors further improved the efficacy of tumor theranostics, such as those using magnetic resonance imaging, chemotherapy, and photothermal therapy.

Vincristine-loaded platelets coated with anti-CD41 mAbs: a new macrophage targeting proposal for the treatment of immune thrombocytopenia.

Immune thrombocytopenia (ITP) is an autoimmune disorder in which platelet-reactive autoantibodies accelerate the destruction of platelets. Macrophages play an important role in ITP through Fc receptor (FcR)-mediated antigen presenting and platelet clearance. In this study, a novel drug delivery system of vincristine-loaded platelets coated with anti-CD41 mAbs (CD41-VCR-PLT, CD41-VLP) was successfully established. The therapeutic effects and safety of CD41-VLP in vitro and in vivo were evaluated, and the possible mechanism was also explored. The results showed that PLT-CD41 could load VCR with high drug loading (DL) and encapsulation efficiency (EE), which were up to 41.16 ± 1.92% and 60.73 ± 2.79%, respectively, where platelets had no obvious morphological or functional changes. CD41-VLP could facilitate vincristine accumulation in macrophages, where the intracellular VCR concentration was 30.72 ± 3.11% at 72 h, which was significantly increased compared with the other groups (P < 0.01), thus inhibiting macrophage cell viability and inducing apoptosis. The cell viability inhibition rate and total apoptosis rate were 73.06 ± 5.26% and 69.70 ± 4.26%, respectively, both much higher than those of the other groups (P < 0.05). In the ITP mouse model, CD41-VLP increased the platelet count in peripheral blood, which was 720 ± 197.98 × 109 L-1, and significantly improved the platelet count compared with that in the VCR group (P < 0.05); moreover, it reduced the systemic toxicity and peripheral neurotoxicity of vincristine. The possible mechanism was that CD41-VLP could precisely target M1 macrophages in spleen and liver tissues through FcγR, thus reducing the platelet destruction caused by M1 macrophages. Therefore, CD41-VLP provides a new targeted therapy for ITP treatment.

Development of a stable single-vial liposomal formulation for vincristine.

Background: Vincristine is a potent therapeutic agent with well-defined activity against hematologic malignancies and solid tumors. It is a cell-cycle specific drug with concentration and exposure duration dependent activity. When used by liposomal delivery, it exhibits enhanced anti-tumor activity. However, vincristine liposome formulation in the clinic is supplied as a 3-vial-kit due to lacking sufficient stability. So it has to be prepared in situ prior to use through a multi-step process. Purpose: The purpose here is to develop a more stable and ready-to-use liposomal formulation for vincritstine in one vial. Patients and methods: A series of preparations were investigated based on sphingomyelin/cholesterol/PEG2000-DSPE lipid composition, with different drug/lipid (D/L) ratios (1/10, 1/5, 1/2), using an active sucrose octasulfate triethylamine salt gradient loading method. In this work, compared to generic vincristine sulfate liposome injection (GVM), the stability both in vivo and in vitro and efficacy in vivo of novel vincristine liposomes were investigated. Results: It was shown that the degradation of vincristine during 2-8°C storage was significantly decreased from 8.2% in 1 month (GVM) to 2.9% in 12 months (D/L ratio 1/5). The half-time for sphingomyelin/cholesterol/PEG2000-DSPE liposomes in vivo could be adjusted from 17.4 h (D/L ratio 1/10) to 22.7 h (D/L ratio 1/2) in rats, while the half-time for GVM was only 11.1 h. The increase in drug retention contributed to the lower in vivo toxicity. The antitumor efficacy was evaluated using a human melanoma tumor model and showed remarkable improvement compared to GVM. Conclusion: The study demonstrates that the new formulation with the drug/lipid ratio of 1/5 owns a higher encapsulation efficiency, better stability, lower toxicity and superior antitumor efficacy, which is screened out for further development.

Hydrogel implants for transscleral drug delivery for retinoblastoma treatment.

Retinoblastoma (Rb) is the most common primary malignant intraocular tumor in children which develops from the retinal stem cells. Systemic chemotherapy is the typical therapeutic treatment and though most children survive Rb, they often lose their vision, or the eye needs to be enucleated. Regarding to the pure availability of the target tumor by systemic chemotherapy, the local anticancer drug administration would be advantageous to increase the local drug concentration and minimize adverse side effects of chemotherapy. The present paper describes a new hydrogel implant enabled to deliver therapeutically active doses of low molecular weight hydrophilic antitumor drugs topotecan and vincristine. The hydrogel implant is proposed as bi-layered with an inner hydrophilic layer from 2-hydroxyethyl methacrylate (HEMA) serving as a reservoir of the chemotherapeutic agent and an outer hydrophobic layer from 2-ethoxyethyl methacrylate (EOEMA) acting as a barrier to protect the surrounding vascularized tissue against cytotoxicity of the delivered chemotherapeutics. The experiments with enucleated pig eyes demonstrated the ability of tested drugs to diffuse through sclera and reach the vitreous humor. HEMA-based hydrogels were examined in terms of sorption, release and transport properties, showing the possibility of adjusting the loading capacity and diffusion of the drugs by the degree of crosslinking. The EOEMA-based gels proved to be an inert for drug sorption and diffusion. A chorioallantoic membrane assay demonstrated excellent biocompatibility of unloaded hydrogels, and in vitro experiments confirmed significant cytotoxicity of drug-loaded hydrogels against a Rb cell line; 2 days for those topotecan-loaded and a minimum of 6 days for vincristine-loaded hydrogels. The bi-layered hydrogel implant can be considered promising for local administration of active agents to eye-globe for the treatment of Rb and also other ocular disorders.

Formulation and Characterization of Spray-Dried Powders Containing Vincristine-Liposomes for Pulmonary Delivery and Its Pharmacokinetic Evaluation From In Vitro and In Vivo.

Vincristine (VCR) has been used in the treatment of lung cancer. To improve its efficacy, the designs of elevating lung exposure to drug and decreasing the clearance with extended time were brought out. Pulmonary delivery is regarded as a good choice in pulmonary diseases treatment. Spray-drying is a technology for the preparation of drugs that can be delivered to lung via a dry powder inhaler. The results showed an appropriate particle size and shape for the pulmonary delivery. The aerosol behaved a sustained-release profile while VCR solution released rapidly within 10 h. The antitumor activity was characterized by 3-(4, 5-dimethylthiazol-2-yl) -2, 5-diphenyltetrazolium bromide assay, and half maximal inhibitory concentration values of VCR-liposomes spray-dried powder were 24.42 ± 1.88 nM and 55.28 ± 4.76 nM in MCF-7 and A549 cells, respectively. Compared with the free VCR, the aerosol performed better pharmacokinetic behavior: increased maximum concentration (630.8%) and systemic exposure (429.6%) and decreased elimination half-life (81.1%). The clearance was decreased by 83.2%. Comprehensively, the pulmonary delivery seemed to be a recommendable way to effectively treat the pulmonary disease.

Relapsed T Cell ALL: Current Approaches and New Directions.

PURPOSE OF REVIEW: Patients with relapsed T cell acute lymphoblastic leukemia (T-ALL) have limited therapeutic options and a poor prognosis. Although a variety of salvage chemotherapy regimens may be used, response rates are unsatisfactory. This article summarizes current approaches and promising emerging strategies for the treatment of relapsed T-ALL. RECENT FINDINGS: Although nelarabine is the only agent approved specifically for T-ALL, recent studies have identified a variety of genetic alterations and signaling pathways that are critical in its pathogenesis. Based on these findings, a number of small-molecule inhibitors and other targeted therapies are being studied for relapsed T-ALL, including gamma-secretase inhibitors, BCL-2 inhibitors, cyclin-dependent kinase inhibitors, and mTOR inhibitors. In addition, pre-clinical studies of chimeric antigen receptor T cells targeting CD5 and CD7 as well as the monoclonal antibody daratumumab have shown promising results for T-ALL. Relapsed T-ALL currently remains challenging to treat, but recent pre-clinical studies of targeted and immunotherapeutic agents have shown encouraging results. A number of clinical trials investigating these approaches for T-ALL are currently underway.

Safe and Effective Delivery of Antitumor Drug Using Mesenchymal Stem Cells Impregnated with Submicron Carriers.

An important area in modern malignant tumor therapy is the optimization of antitumor drugs pharmacokinetics. The use of some antitumor drugs is limited in clinical practice due to their high toxicity. Therefore, the strategy for optimizing the drug pharmacokinetics focuses on the generation of high local concentrations of these drugs in the tumor area with minimal systemic and tissue-specific toxicity. This can be achieved by encapsulation of highly toxic antitumor drug (vincristine (VCR) that is 20-50 times more toxic than widely used the antitumor drug doxorubicin) into nano- and microcarriers with their further association into therapeutically relevant cells that possess the ability to migrate to sites of tumor. Here, we fundamentally examine the effect of drug carrier size on the behavior of human mesenchymal stem cells (hMSCs), including internalization efficiency, cytotoxicity, cell movement, to optimize the conditions for the development of carrier-hMSCs drug delivery platform. Using the malignant tumors derived from patients, we evaluated the capability of hMSCs associated with VCR-loaded carriers to target tumors using a three-dimensional spheroid model in collagen gel. Compared to free VCR, the developed hMSC-based drug delivery platform showed enhanced antitumor activity regarding those tumors that express CXCL12 (stromal cell-derived factor-1 (SDF-1)) gene, inducing directed migration of hMSCs via CXCL12 (SDF-1)/CXCR4 pathway. These results show that the combination of encapsulated antitumor drugs and hMSCs, which possess the properties of active migration into tumors, is therapeutically beneficial and demonstrated high efficiency and low systematic toxicity, revealing novel strategies for chemotherapy in the future.

Investigation of Potential Paraoxonase-I Inhibitors by Kinetic and Molecular Docking Studies: Chemotherapeutic Drugs.

BACKGROUND: Metabolic processes in living organisms are closely related to the catalytic activity of enzymes. Changes in enzyme activity cause various diseases e.g., neurological, cancer, metabolic and cardiovascular. Most of the current therapeutic drugs available in clinical utilization function as enzyme inhibitors. OBJECTIVE: The main goal of the current study to contribute to this growing drug design area (such as medication discovery and development) by investigating protein-drug interactions. METHODS: The paraoxonase-I (PON1) enzyme was purified from human serum by using different and simple chromatographic techniques. Additionally, it was investigated inhibition effects of some chemotherapeutic drugs on the PON1. RESULTS: The purification results for PON1 depicted a 3880.83 EU/mg proteins specific activity and the molecular weight was calculated as 43 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. These drugs found to strongly inhibit PON1, with IC50 values ranging from 0.222±0.002 to 688.300±0.897 µM. Ki constants for vincristine sulfate, epirubicin hydrochloride, and doxorubicin hydrochloride were determined to be 0.235±0.032 µM, 221.400±29.270 µM, and 913.300±201.000 µM, respectively. CONCLUSION: These drugs showed in competitive inhibition. Also, the molecular docking poses of these agents inside the catalytic sites of 1V04 and 3SRE were analysis.

Ecotoxicity risk of presence of two cytostatic drugs: Bleomycin and vincristine and their binary mixture in aquatic environment.

Cytostatic drugs have become one of the greatest environmental threats. They occur in surface, ground and even drinking water. Their key emission sources are hospital effluents, municipal wastewater, as well as drug manufacturers and their effluents. These compounds are extremely stable in natural waters and they are not significantly removed during wastewater treatment, because they are resistant to biodegradation. The aim of this work was to establish possible negative effects of chosen cytostatics: bleomycin and vincristine on the three trophic levels of surface waters. A single agent acute toxicity test was conducted on representatives of the producer - an aquatic freshwater plant Lemna minor, the consumer - crustaceans Daphnia magna, and the decomposer - bacteria Pseudomonas putida. Binary mixture tests were performed according to the Concentration Addition, Response Additivity, and Independent Action models. Both substances had a different effect on the tested organisms; bleomycin could be classified as a very toxic, while vincristine as a toxic water pollutant. Half maximal effective concentration (EC50) values designed in the presented single agent acute toxicity studies are < 10 mg/L in all the tests with bleomycin as well as vincristine conducted on L. minor. In tests with vincristine performed on D. magna and P. putida EC50 > 100 mg/L. The highest toxicity is demonstrated by bleomycin towards the aquatic freshwater plant (EC50 = 0.2 mg/L). The binary mixture of the tested chemicals showed antagonistic effects of environmental concern.

Stability of vincristine sulfate, doxorubicin hydrochloride and etoposide phosphate admixtures in polyisoprene elastomeric pump supporting transition of the EPOCH regimen to outpatient care.

BACKGROUND: The EPOCH regimen, consisting of vincristine sulfate, doxorubicin hydrochloride, and etoposide phosphate, is typically administered by continuous infusion over four days to oncology inpatients. If the EPOCH regimen was available to be administered through portable elastomeric pumps, chemotherapy could be transitioned to an outpatient setting, reducing inpatient bed days and overall healthcare costs. However, a lack of stability data for the admixtures in the elastomeric infusion devices currently prevents the transition of the regime to an outpatient setting. The purpose of this study is to determine the physical and chemical stability of the admixture in polyisoprene elastomeric pumps under different storage conditions to support the transition of the EPOCH regime to an outpatient setting. METHODS: The physico-chemical stability of three admixtures at a range of clinically relevant concentrations compounded in polyisoprene elastomeric infusors was determined when refrigerated at 2-6℃ over a 14-day period followed by 35℃ up to 7 days in the dark, and under standardized fluorescent light to simulate scenarios in clinical practice. RESULTS: All tested admixtures were compatible and the drugs were stable in the elastomeric infusors for up to 14 days when stored at 2-6℃ followed by 7 days at 35℃ in the dark, with nominal losses of <5%. The major degradant of etoposide phosphate was its active form etoposide. There was no degradation (<1% loss) found when the admixture was exposed to a standardized fluorescent light dose of 80 klux-h (25℃) for 10 h. The temperature and light conditions the infusors were exposed to during the stability study were more severe than the conditions determine during clinical administration. CONCLUSION: The extended stability of the three infusional admixtures compounded in elastomeric infusion pumps demonstrated herein permits advance preparation and storage of these drugs, reducing pharmacy compounding resources. The demonstrated stability at 35℃ and under light exposure, conditions more severe than those experienced during clinical practice, support continuous infusions for up to seven days from the elastomeric infusors without a loss of potency. The proven stability of the EPOCH regimens in the tested elastomeric infusion device supports the transition of treatment to an outpatient setting which will reduce inpatient bed days and overall healthcare costs.

Ajmaline, Oxindole, and Cytotoxic Macroline-Akuammiline Bisindole Alkaloids from Alstonia penangiana.

Examination of the EtOH extract of the Malayan Alstonia penangiana resulted in the isolation of 10 new alkaloids, comprising two ajmaline (1, 2), four macroline oxindole (3-6), and four macroline-akuammiline bisindole alkaloids (7-10). The structures of these alkaloids were determined based on analysis of the spectroscopic data and, in the case of the oxindole 6 and the bisindole alkaloid 7, also confirmed by X-ray diffraction analysis. The bisindole alkaloids 7 and 8 showed pronounced in vitro growth inhibitory activity against an array of human cancer cell lines, including KB, vincristine-resistant KB, PC-3, LNCaP, MCF7, MDA-MB-231, HT-29, HCT 116, and A549 cells with IC50 values in the 0.3-8.3 µM range.