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Natural Product Reports Jul 2023Many researchers in the natural product sciences dream of discovering a successful drug. For almost all of us, this dream will never be realized. Among the heroes of our... (Review)
Review
Many researchers in the natural product sciences dream of discovering a successful drug. For almost all of us, this dream will never be realized. Among the heroes of our past, though, there is a team whose efforts led to the discovery of not one but two new drugs. Dr Monroe Wall and Dr Mansukh Wani isolated and solved the structures for taxol and camptothecin, plant-based compounds that continue to play a critical role in cancer therapy today. Since the 1960s and 1970s when Wall, Wani and collaborators did their seminal work, there have been tremendous technological advances in the natural product sciences. With access to most sophisticated technology, it might be expected that the rate of discovery of new drugs from plants and other sources would have sped up. However, this has not come to pass. Why is this? Is it that the promise of new drug candidates from plant-based sources has been exhausted? Has our fascination with new technologies and with the promise of the genomics revolution caused us to stop investing effort and resources in the practices that are proven to yield success? With this Viewpoint, we share the story of taxol's discovery, highlighting critical challenges that were overcome and considering their relevance to botanical natural products drug discovery today. We hope that consideration of lessons learned from the past will help fuel success by researchers currently studying plants with the goal of discovering promising therapeutic leads.
Topics: Humans; Antineoplastic Agents; Antineoplastic Agents, Phytogenic; Biological Products; Neoplasms; Paclitaxel; Plants; Population Health
PubMed: 37449327
DOI: 10.1039/d3np00017f -
Frontiers in Bioscience (Landmark... Oct 2022Although controversially discussed, paclitaxel is the only clinically proven drug that inhibits restenosis when released from drug-coated balloons (DCBs). Limus drugs...
BACKGROUND
Although controversially discussed, paclitaxel is the only clinically proven drug that inhibits restenosis when released from drug-coated balloons (DCBs). Limus drugs are currently being explored as alternatives. The aim of the preclinical studies was to investigate drug candidates beyond paclitaxel considered for balloon coating.
METHODS
Drugs were tested with respect to dissolution in organic solvents, coating on balloons, and drug transfer to the vessel wall. Inhibition of neointimal proliferation was tested in the porcine model of coronary in-stent stenosis. Intravascular drug treatment was achieved by DCBs at the time of stent implantation.
RESULTS
Coating had to be adjusted for each drug. Doses on the balloons ranged from 1.0 to 8.6 μg/mm2 balloon surface. Satisfactory amounts of drug ranging from 5% to 29% of initial doses were transferred into the vessel wall. Angiographic parameters such as late lumen loss (LLL) at 4 weeks did not show reduction of in-stent neointimal proliferation by treatment with arsenic trioxide (0.87 ± 0.44 mm), betamethasone dipropionate (1.00 ± 0.54 mm), bortezomib (1.74 ± 0.46 mm), green tea extract (1.24 ± 0.51 mm), fantolon, an epothilone (0.86 ± 0.61 mm), methotrexate (1.09 ± 0.72 mm), and thalidomide (1.59 ± 0.55 mm) compared to treatment with uncoated balloons (1.07 ± 0.60 mm), while coatings with paclitaxel reliably reduced in-stent stenosis (LLL = 0.36 ± 0.25 mm).
CONCLUSIONS
Despite the proven antiproliferative and/or anti-inflammatory effect of the drugs, none of the coatings significantly reduced LLL compared to uncoated balloons and thus, based on the results presented here, none of the tested coatings may be considered a substitute for the paclitaxel-based coatings currently in clinical use.
Topics: Swine; Animals; Paclitaxel; Angioplasty, Balloon, Coronary; Constriction, Pathologic; Stents; Coated Materials, Biocompatible; Treatment Outcome
PubMed: 36336862
DOI: 10.31083/j.fbl2710283 -
Molecular Cancer Jun 2022Triple-negative breast cancers (TNBCs) are clinically aggressive subtypes of breast cancer. TNBC is difficult to treat with targeted agents due to the lack of commonly...
BACKGROUND
Triple-negative breast cancers (TNBCs) are clinically aggressive subtypes of breast cancer. TNBC is difficult to treat with targeted agents due to the lack of commonly targeted therapies within this subtype. Androgen receptor (AR) has been detected in 12-55% of TNBCs. AR stimulates breast tumor growth in the absence of estrogen receptor (ER), and it has become an emerging molecular target in TNBC treatment.
METHODS
Ceritinib is a small molecule inhibitor of tyrosine kinase and it is used in the therapy of non-small lung cancer patients. Enzalutamide is a small molecule compound targeting the androgen receptor and it is used to treat prostate cancer. Combination therapy of these drugs were investigated using AR positive breast cancer mouse xenograft models. Also, combination treatment of ceritinib and paclitaxel investigated using AR and AR low mouse xenograft and patient derived xenograft models.
RESULTS
We screened 133 FDA approved drugs that have a therapeutic effect of AR TNBC cells. From the screen, we identified two drugs, ceritinib and crizotinib. Since ceritinib has a well- defined role in androgen independent AR signaling pathways, we further investigated the effect of ceritinib. Ceritinib treatment inhibited RTK/ACK/AR pathway and other downstream pathways in AR TNBC cells. The combination of ceritinib and enzalutamide showed a robust inhibitory effect on cell growth of AR TNBC cells in vitro and in vivo. Interestingly Ceritinib inhibits FAK-YB-1 signaling pathway that leads to paclitaxel resistance in all types of TNBC cells. The combination of paclitaxel and ceritinib showed drastic inhibition of tumor growth compared to a single drug alone.
CONCLUSIONS
To improve the response of AR antagonist in AR positive TNBC, we designed a novel combinational strategy comprised of enzalutamide and ceritinib to treat AR TNBC tumors through the dual blockade of androgen-dependent and androgen-independent AR signaling pathways. Furthermore, we introduced a novel therapeutic combination of ceritinib and paclitaxel for AR negative or AR-low TNBCs and this combination inhibited tumor growth to a great extent. All agents used in our study are FDA-approved, and thus the proposed combination therapy will likely be useful in the clinic.
Topics: Androgens; Animals; Cell Line, Tumor; Humans; Mice; Paclitaxel; Pyrimidines; Receptors, Androgen; Sulfones; Triple Negative Breast Neoplasms
PubMed: 35768871
DOI: 10.1186/s12943-022-01601-0 -
The Oncologist Sep 2023Loss of PTEN function leads to increased PI3Kβ signaling. AZD8186, a selective PI3Kβ/δ inhibitor, has shown anti-tumor activity in PTEN-deficient preclinical models....
BACKGROUND
Loss of PTEN function leads to increased PI3Kβ signaling. AZD8186, a selective PI3Kβ/δ inhibitor, has shown anti-tumor activity in PTEN-deficient preclinical models. Although the combination of AZD8186 and paclitaxel was well tolerated, limited clinical efficacy was observed in advanced gastric cancer with PTEN loss.
METHODS
In the phase Ib dose-escalation, subjects with advanced solid tumors received oral AZD8186 (60 mg or 120 mg; twice daily (BID); 5 days on/2 days off) plus intravenous paclitaxel (70 mg/m2 or 80 mg/m2; days 1, 8, and 15) every 4 weeks. In the phase II part, MRGC patients with PTEN loss or PTEN/PIK3CB gene abnormality were enrolled and received recommended phase II dose (RP2D) of AZD8186 plus paclitaxel. Primary endpoints were to determine maximum tolerated dose (MTD) and RP2D in phase Ib and 4-month progression-free survival (PFS) rate in phase II.
RESULTS
In phase Ib, both MTD and RP2D were determined at paclitaxel 80 mg/m2 and AZD8186 120 mg BID. In phase II, 18 patients were enrolled [PTEN loss (n = 18) and PIK3CB mutation (n = 1)]. The 4-month PFS rate was 18.8% (3 of 16 evaluable patients) and further enrollment stopped due to futility.
CONCLUSION
Although the combination of AZD8186 and paclitaxel was well tolerated, limited clinical efficacy was observed.ClinicalTrials.gov Identifier: NCT04001569.
Topics: Humans; Aniline Compounds; Antineoplastic Combined Chemotherapy Protocols; Chromones; Maximum Tolerated Dose; Paclitaxel; Repressor Proteins; Stomach Neoplasms
PubMed: 37036671
DOI: 10.1093/oncolo/oyad059 -
The American Journal of Managed Care Jan 2021Intravenous (IV) taxane therapy for metastatic breast cancer (mBC) has been associated with toxicities and demanding dosing schedules, which can limit treatment...
BACKGROUND
Intravenous (IV) taxane therapy for metastatic breast cancer (mBC) has been associated with toxicities and demanding dosing schedules, which can limit treatment effectiveness.
OBJECTIVES
To assess treatment patterns, toxicities, and costs in women with mBC initiating IV paclitaxel or IV nab-paclitaxel.
METHODS
Adult women diagnosed with BC from January 1, 2014, to September 30, 2018, were identified in the MarketScan Commercial and MarketScan Medicare Supplemental databases. Women had a metastatic disease diagnosis and newly initiated treatment with IV paclitaxel/nab-paclitaxel (first administration date was considered the index date), and continuous enrollment for at least 12 months prior to and at least 3 months following the index date. Treatment discontinuation, dose reductions, toxicities, and health care utilization and costs per patient per month (PPPM) were assessed over the full follow-up and the index line of IV paclitaxel/nab-paclitaxel therapy (Index LOT).
RESULTS
The sample included 8890 women aged 54.6 (±10.9) years, followed for 18.9 (±13.5) months. Most (82.0%) initiated IV paclitaxel/nab-paclitaxel monotherapy; 83.1% had early discontinuation (<18 weeks of treatment) of the Index LOT. Among the 6943 women eligible for the dose-change analysis, 42.4% evidenced an IV paclitaxel/nab-paclitaxel dose reduction ≥10% during the Index LOT. The most common toxicities during the Index LOT were gastrointestinal upset (30.5%), myelotoxicity (27.0%), infection (26.2%), general symptoms (25.9%), and chemotherapy-induced peripheral neuropathy (22.7%). Over follow-up, 39.7% of women had an inpatient admission and 43.0% had an emergency department visit. The mean of all-cause total costs was $11,991 PPPM, while BC-related total costs were $5320 PPPM.
CONCLUSIONS
Many mBC patients initiating IV paclitaxel/nab-paclitaxel experienced dose reductions, toxicities, and/or early discontinuation of the Index LOT, which may limit treatment effectiveness. More tolerable treatments with reduced dosing complexity could improve mBC treatment and help contain costs.
Topics: Adult; Aged; Albumins; Antineoplastic Combined Chemotherapy Protocols; Breast Neoplasms; Cost of Illness; Female; Humans; Medicare; Paclitaxel; United States
PubMed: 33395242
DOI: 10.37765/ajmc.2021.88561 -
Journal of Pharmaceutical and... Aug 2019We have developed a high performance liquid chromatography mass spectrometry method for quantitating paclitaxel and its 6-alpha-OH and 3-para-OH metabolites in 0.1 mL...
We have developed a high performance liquid chromatography mass spectrometry method for quantitating paclitaxel and its 6-alpha-OH and 3-para-OH metabolites in 0.1 mL human plasma. After MTBE liquid-liquid extraction, chromatographic separation was achieved with a Phenomenex synergy polar reverse phase (4 μm, 2 mm × 50 mm) column and a gradient of 0.1% formic acid in acetonitrile and water over an 8 min run time. Mass spectrometric detection was performed on an ABI SCIEX 4000Q with electrospray, positive-mode ionization. The assay was linear from 10-10,000 ng/mL for paclitaxel and 1-1000 ng/mL for both metabolites and proved to be accurate (94.3-110.4%) and precise (<11.3%CV). Recovery from plasma was 59.3-91.3% and matrix effect was negligible (-3.5 to 6.2%). Plasma freeze thaw stability (90.2-107.0%), stability for 37 months at -80 °C (89.4-112.6%), and stability for 4 h at room temperature (87.7-100.0%) were all acceptable. This assay will be an essential tool to further define the metabolism and pharmacology of paclitaxel and metabolites in the clinical setting. The assay may be utilized for therapeutic drug monitoring of paclitaxel and may also reveal the CYP2C8 and CYP3A4 activity phenotype of patients.
Topics: Antineoplastic Agents, Phytogenic; Blood Specimen Collection; Chromatography, High Pressure Liquid; Clinical Trials, Phase I as Topic; Cytochrome P-450 CYP2C8; Cytochrome P-450 CYP3A; Drug Monitoring; Drug Stability; Humans; Paclitaxel; Reproducibility of Results; Tandem Mass Spectrometry
PubMed: 31022613
DOI: 10.1016/j.jpba.2019.04.027 -
Scientific Reports Jun 2023This study examines the electrical properties of isolated brain microtubules (MTs), which are long hollow cylinders assembled from αβ-tubulin dimers that form...
This study examines the electrical properties of isolated brain microtubules (MTs), which are long hollow cylinders assembled from αβ-tubulin dimers that form cytoskeletal structures engaged in several functions. MTs are implicated in sensory functions in cilia and flagella and cellular activities that range from cell motility, vesicular traffic, and neuronal processes to cell division in the centrosomes and centrioles. We determined the electrical properties of the MTs with the loose patch clamp technique in either the presence or absence of the MT stabilizer Paclitaxel. We observed electrical oscillations at different holding potentials that responded accordingly in amplitude and polarity. At zero mV in symmetrical ionic conditions, a single MT radiated an electrical power of 10 W. The spectral analysis of the time records disclosed a single fundamental peak at 39 Hz in the Paclitaxel-stabilized MTs. However, a richer oscillatory response and two mean conductances were observed in the non-Paclitaxel MTs. The findings evidence that the brain MTs are electrical oscillators that behave as "ionic-based" transistors to generate, propagate, and amplify electrical signals.
Topics: Microtubules; Tubulin; Paclitaxel; Polymers; Electricity
PubMed: 37349383
DOI: 10.1038/s41598-023-36801-1 -
Biomolecules Dec 2022Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of several chemotherapeutic agents, such as Paclitaxel. The main symptoms of CIPN are pain and...
Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of several chemotherapeutic agents, such as Paclitaxel. The main symptoms of CIPN are pain and numbness in the hands and feet. Paclitaxel is believed to accumulate in the dorsal root ganglia and free nerve endings. Novel therapeutic agents might help to mitigate or prevent Paclitaxel toxicity on dorsal root ganglion (DRG) neurons. Thus, we used primary DRG neurons as a model to investigate the potential neuroprotective effects of the endocannabinoid-like substance, palmitoylethanolamide (PEA). DRG neurons were isolated from cervical to sacral segments of spinal nerves of Wister rats (6-8 weeks old). After isolation and purification of neuronal cell populations, different concentrations of Paclitaxel (0.01-10 µM) or PEA (0.1-10 µM) or their combination were tested on cell viability by MTT assay at 24 h, 48, and 72 h post-treatment. Furthermore, morphometric analyses of neurite length and soma size for DRG neurons were performed. Adverse Paclitaxel effects on cell viability were apparent at 72 h post-treatment whereas Paclitaxel significantly reduced the neurite length in a concentration-dependent manner nearly at all investigated time points. However, Paclitaxel significantly increased the size of neuronal cell bodies at all time windows. These phenotypic effects were significantly reduced in neurons additionally treated with PEA, indicating the neuroprotective effect of PEA. PEA alone led to a significant increase in neuron viability regardless of PEA concentrations, apparent improvements in neurite outgrowth as well as a significant decrease in soma size of neurons at different investigated time points. Taken together, PEA showed promising protective effects against Paclitaxel-related toxicity on DRG neurons.
Topics: Rats; Animals; Paclitaxel; Ganglia, Spinal; Antineoplastic Agents, Phytogenic; Rats, Wistar; Peripheral Nervous System Diseases; Sensory Receptor Cells
PubMed: 36551301
DOI: 10.3390/biom12121873 -
Advanced Science (Weinheim,... Nov 2022Chemotherapy, although effective against primary tumors, may promote metastasis by causing the release of proinflammatory factors from damaged cells. Here, polymeric...
Chemotherapy, although effective against primary tumors, may promote metastasis by causing the release of proinflammatory factors from damaged cells. Here, polymeric nanoparticles that deliver chemotherapeutics and scavenge proinflammatory factors simultaneously to inhibit chemotherapy-induced breast cancer metastasis are developed. The cationic nanoparticles can adsorb cell-free nucleic acids (cfNAs) based on charge-charge interaction, which downregulates the expression of Toll-like receptors and then reduces the secretion of inflammatory cytokines. Through in vitro structural optimization, cationic polyamidoamine (PAMAM) dendrimers modified with drug-binding dodecyl groups and diethylethanolamine surface groups (PAMAM-G3-C12 -DEEA ) exhibit the most desirable combination of nanoparticle size (≈140 nm), drug loading, cytotoxicity, cfNA binding, and anti-inflammatory activity. In the mouse models of breast cancer metastasis, paclitaxel-loaded nanoparticles reduce serum levels of cfNAs and inflammatory cytokines compared with paclitaxel treatment alone and inhibit both primary tumor growth and tumor metastasis. Additionally, no significant side effects are detected in the serum or major organs. These results provide a strategy to deliver chemotherapeutics to primary tumors while reducing the prometastatic effects of chemotherapy.
Topics: Mice; Animals; Neoplasms; Paclitaxel; Nanoparticles; Antineoplastic Agents; Cytokines
PubMed: 36220339
DOI: 10.1002/advs.202203949 -
Molecules (Basel, Switzerland) Nov 2022Lung cancer is the leading cause of cancer-related deaths globally. Despite current treatment approaches that include surgery, chemotherapy, radiation and... (Review)
Review
Lung cancer is the leading cause of cancer-related deaths globally. Despite current treatment approaches that include surgery, chemotherapy, radiation and immunotherapies, lung cancer accounted for 1.79 million deaths worldwide in 2020, emphasizing the urgent need to find novel agents and approaches for more effective treatment. Traditionally, chemicals derived from plants, such as paclitaxel and docetaxel, have been used in cancer treatment, and in recent years, research has focused on finding other plant-derived chemicals that can be used in the fight against lung cancer. Ursolic acid is a polyphenol found in high concentrations in cranberries and other fruits and has been demonstrated to have anti-inflammatory, antioxidant and anticancer properties. In this review, we summarize recent research examining the effects of ursolic acid and its derivatives on lung cancer. Data from in vitro cell culture and in vivo animal studies show potent anticancer effects of ursolic acid and indicate the need for clinical studies.
Topics: Animals; Cell Proliferation; Triterpenes; Lung Neoplasms; Paclitaxel; Ursolic Acid
PubMed: 36364289
DOI: 10.3390/molecules27217466