Characteristics, Properties and Analytical Methods of Paclitaxel: A Review

In vivo Serum Enabled Production of Ultrafine Nanotherapeutics for Cancer Treatment

Systemic delivery of hydrophobic anti-cancer drugs with nanocarriers, particularly for drug-resistant and metastatic cancer, remain a challenge because of the difficulty to achieve high drug loading, while maintaining a small hydrodynamic size and colloid stability in blood to ensure delivery of an efficacious amount of drug to tumor cells. Here we introduce a new approach to address this challenge. In this approach, nanofibers of larger size with good drug loading capacity are first constructed by a self-assembly process, and upon intravascular injection and interacting with serum proteins in vivo, these nanofibers break down into ultra-fine nanoparticles of smaller size that inherit the drug loading property from their parent nanofibers. We demonstrate the efficacy of this approach with a clinically available anti-cancer drug: paclitaxel (PTX). In vitro, the PTX-loaded nanoparticles enter cancer cells and induce cellular apoptosis. In vivo, they demonstrate prolonged circulation in blood, induce no systemic toxicity, and show high potency in inhibiting tumor growth and metastasis in both mouse models of aggressive, drug-resistant breast cancer and melanoma. This study points to a new strategy toward improved anti-cancer drug delivery and therapy.

Effective in vitro delivery of paclitaxel by nanocargo of mesoporous polycaprolactone against triple negative breast cancer cells by minimalizing drug dose

Among the breast cancers, triple negative breast cancer (TNBC) has relatively poor outcomes with a lower survival rate and personalised chemotherapy is the only option available for treatment. Currently in the biomedical domain, nanomaterials with porous morphology have revealed their tremendous possibilities to be used as a nanocarrier in treating cancer by offering void space to encapsulate/entrap biological agents. However, the development of nanocarrier-based targeted therapy with high therapeutic efficacy and fewer side effects to normal cells is always a challenge. Here, we have developed nanocargos based on biodegradable mesoporous PCL (polycaprolactone) of approx. diameter of 75 nm by template removal synthesis techniques. Succeeding the comparative analysis of the nanocarriers, the efficiencies of core shell PCL-mZnO (PZ) and mesoporous PCL (HPZ) to deliver paclitaxel (Taxol/T) into breast cancer cells, is investigated. We found that HPZ nanocapsules have less cytotoxicity and drug loading efficiency of about 600 μg mg-1. The Taxol-loaded nanoparticles (T-HPZ) have exhibited more cytotoxicity than Taxol alone treated cancer cells. Furthermore, T-HPZ treated MDA-MB231 cells are accumulated at G2/M phase of the cell cycle and eventually undergo apoptosis. In support of this, anchorage independent growth of MDA-MB231 cells are significantly inhibited by T-HPZ treatment. Together, our findings suggest that T-HPZ-based paclitaxel (Taxol/T) loaded nanoparticles provide a novel therapeutic option in the treatment of TNBC.

Alternative sources and metabolic engineering of Taxol: Advances and future perspectives

Paclitaxel is one of the strong plant-derived anti-cancer drugs that was first isolated from the Pacific yew. Despite many paclitaxel's clinical successes, the limited accessibility of paclitaxel for clinical trials is recognized as the most important challenge. Thus, researchers are continuously trying to find the innovative ways to meet the community's need for this medicine. In the first step, the alternative sources for Taxol supply were recognized, such as Taxus genus, other plant genera, and endophytic fungi. In the next step, the biosynthetic pathways of Taxol or related metabolites were manipulated in the original organisms, or introduced to heterologous systems and then were manipulated in them. Here, a range of metabolic manipulating approaches have been successfully developed to redirect the metabolic flux toward Taxol, including promoter engineering, enzyme engineering, overexpressing the bottleneck enzymes, over- or down-regulation of transcription factors, activation of the cryptic genes, removing/minimizing the flux for competing pathways, tunable regulation of the metabolic pathway, and increasing the supplies of precursors. In this review, we discuss research progress on the alternative Taxol sources and its metabolic manipulating, and we suggest recent challenges and future perspectives.

Therapeutic Potential of Diosgenin and Its Major Derivatives against Neurological Diseases: Recent Advances

Diosgenin (DG), a well-known steroidal sapogenin, is present abundantly in medicinal herbs such as Dioscorea rhizome, Dioscorea villosa, Trigonella foenum-graecum, Smilax China, and Rhizoma polgonati. DG is utilized as a major starting material for the production of steroidal drugs in the pharmaceutical industry. Due to its wide range of pharmacological activities and medicinal properties, it has been used in the treatment of cancers, hyperlipidemia, inflammation, and infections. Numerous studies have reported that DG is useful in the prevention and treatment of neurological diseases. Its therapeutic mechanisms are based on the mediation of different signaling pathways, and targeting these pathways might lead to the development of effective therapeutic agents for neurological diseases. The present review mainly summarizes recent progress using DG and its derivatives as therapeutic agents for multiple neurological disorders along with their various mechanisms in the central nervous system. In particular, those related to therapeutic efficacy for Parkinson's disease, Alzheimer's disease, brain injury, neuroinflammation, and ischemia are discussed. This review article also critically evaluates existing limitations associated with the solubility and bioavailability of DG and discusses imperatives for translational clinical research. It briefly recapitulates recent advances in structural modification and novel formulations to increase the therapeutic efficacy and brain levels of DG. In the present review, databases of PubMed, Web of Science, and Scopus were used for studies of DG and its derivatives in the treatment of central nervous system diseases published in English until December 10, 2019. Three independent researchers examined articles for eligibility. A total of 150 articles were screened from the above scientific literature databases. Finally, a total of 46 articles were extracted and included in this review. Keywords related to glioma, ischemia, memory, aging, cognitive impairment, Alzheimer, Parkinson, and neurodegenerative disorders were searched in the databases based on DG and its derivatives.

Spectral characteristics of urine from patients with end-stage kidney disease analyzed using Raman Chemometric Urinalysis (Rametrix)

Raman Chemometric Urinalysis (Rametrix^TM) was used to discern differences in Raman spectra from (i) 362 urine specimens from patients receiving peritoneal dialysis (PD) therapy for end-stage kidney disease (ESKD), (ii) 395 spent dialysate specimens from those PD therapies, and (iii) 235 urine specimens from healthy human volunteers. Rametrix^TM analysis includes spectral processing (e.g., truncation, baselining, and vector normalization); principal component analysis (PCA); statistical analyses (ANOVA and pairwise comparisons); discriminant analysis of principal components (DAPC); and testing DAPC models using a leave-one-out build/test validation procedure. Results showed distinct and statistically significant differences between the three types of specimens mentioned above. Further, when introducing “unknown” specimens, Rametrix^TM was able to identify the type of specimen (as PD patient urine or spent dialysate) with better than 98% accuracy, sensitivity, and specificity. Rametrix^TM was able to identify “unknown” urine specimens as from PD patients or healthy human volunteers with better than 96% accuracy (with better than 97% sensitivity and 94% specificity). This demonstrates that an entire Raman spectrum of a urine or spent dialysate specimen can be used to determine its identity or the presence of ESKD by the donor.

Chitosan-based advanced materials for docetaxel and paclitaxel delivery: Recent advances and future directions in cancer theranostics

Paclitaxel (PTX) and docetaxel (DTX) are key members of taxanes with high anti-tumor activity against various cancer cells. These chemotherapeutic agents suffer from a number of drawbacks and it seems that low solubility in water is the most important one. Although much effort has been made in improving the bioavailability of PTX and DTX, the low bioavailability and minimal accumulation at tumor sites are still the challenges faced in PTX and DTX therapy. As a consequence, bio-based nanoparticles (NPs) have attracted much attention due to unique properties. Among them, chitosan (CS) is of interest due to its great biocompatibility. CS is a positively charged polysaccharide with the capability of interaction with negatively charged biomolecules. Besides, it can be processed into the sheet, micro/nano-particles, scaffold, and is dissolvable in mildly acidic pH similar to the pH of the tumor microenvironment. Keeping in mind the different applications of CS in the preparation of nanocarriers for delivery of PTX and DTX, in the present review, we demonstrate that how CS functionalized-nanocarriers and CS modification can be beneficial in enhancing the bioavailability of PTX and DTX, targeted delivery at tumor site, image-guided delivery and co-delivery with other anti-tumor drugs or genes.

Blood-Brain Barrier- and Blood-Brain Tumor Barrier-Penetrating Peptide-Derived Targeted Therapeutics for Glioma and Malignant Tumor Brain Metastases

Glioma is the most common malignant tumor of the central nervous system (CNS). Therapeutic efficacy of glioma treatment is greatly limited by the blood-brain barrier (BBB) and blood-brain tumor barrier (BBTB), which restrict the passage of most drugs into the brain and tumors. Developing drug delivery systems that cross the BBB and BBTB will aid in the treatment of glioma and malignant brain metastases. One emerging solution is to identify peptide vectors that penetrate the BBB/BBTB. Herein, a novel BBB/BBTB-penetrating peptide was identified from the phage-displayed peptide library. Peptide-drug conjugates (PDCs) were derived and applied to treat glioma and breast cancer brain metastases. Antitumor activity was achieved in both tumor models with synergistic effects when combined with the currently used chemotherapy drug temozolomide. The peptide reported herein can serve as a universal vector for shuttling compounds across the BBB; therefore, it may have wide applications for treating brain tumors and other CNS diseases.

Co-Administration Of iRGD Enhances Tumor-Targeted Delivery And Anti-Tumor Effects Of Paclitaxel-Loaded PLGA Nanoparticles For Colorectal Cancer Treatment

BACKGROUND

Nanoparticles exhibit great promise for improving the solubility and tissue-specific distribution of chemotherapeutic agents; however, the passive and highly variable enhanced permeability and retention (EPR) effects observed in tumors frequently leads to insufficient delivery of nanodrugs into tumors. The tumor-penetrating peptide iRGD can actively enhance tumor-selective delivery of nanoparticles into tumors by binding to integrin and interacting with tissue-penetrating receptor neuropilin-1.

MATERIALS AND METHODS

To improve colorectal cancer treatment, in this study, we prepared a paclitaxel (PTX)-loaded PLGA nanoparticle (PLGA-PTX) and evaluated its tumor-targeting and antitumor activity by co-administration with iRGD.

RESULTS

Compared to free PTX, encapsulated PTX retained preferential cytotoxicity toward various colorectal cancer cells while effectively sparing healthy cells. PLGA-PTX treatment resulted in cell cycle arrest at the G2/M phase and apoptosis, leading to inhibition of cancer cell migration and invasion. PLGA-PTX combined with iRGD displayed little enhancement of cytotoxicity in vitro. Despite this, iRGD receptors integrin and neuropilin-1 were found to be primarily overexpressed on abundant tumor vessels in mice bearing colorectal tumors. Consequently, co-administration of nanoparticles with iRGD promoted the selective delivery of nanoparticles into tumor tissues in vivo. Additionally, the combined regimen enhanced the antitumor effects compared to those of each individual reagent.

CONCLUSION

Our findings suggest that PLGA nanoparticles combined with the iRGD peptide provide a promising drug delivery strategy for facilitating active drug accumulation into tumors, given that iRGD receptors are overexpressed on tumor vessels. This co-administration system lacking covalent conjugation provides a more convenient means to combine various therapeutic agents with iRGD to achieve personalized nanotherapy.

Specific driving of the suicide E gene by the CEA promoter enhances the effects of paclitaxel in lung cancer

Classical chemotherapy for lung cancer needs new strategies to enhance its antitumor effect. The cytotoxicity, nonspecificity, and low bioavailability of paclitaxel (PTX) limits their use in this type of cancer. Suicide gene therapy using tumor-specific promoters may increase treatment effectiveness. We used carcinoembryonic antigen (CEA) as a tumor-specific promoter to drive the bacteriophage E gene (pCEA-E) towards lung cancer cells (A-549 human and LL2 mice cell lines) but not normal lung cells (L132 human embryonic lung cell line), in association with PTX as a combined treatment. The study was carried out using cell cultures, tumor spheroid models (MTS), subcutaneous induced tumors and lung cancer stem cells (CSCs). pCEA-E induced significant inhibition of A-549 and LL2 cell proliferation in comparison to L132 cells, which have lower CEA expression levels. Moreover, pCEA-E induced an important decrease in volume growth of A-549 and LL2 MTS producing intense apoptosis, in comparison to L132 MTS. In addition, pCEA-E enhanced the antitumor effects of PTX when combined, showing a synergistic effect. This effect was also observed in A-549 CSCs, which have been related to the recurrence of cancer. The in vivo study corroborated the effectiveness of the pCEA-E-PTX combined therapy, inducing a greater decrease in tumor volume compared to PTX and pCEA-E alone. Our results suggest that the CEA promoter is an excellent candidate for directing E gene expression specifically towards lung cancer cells, and may be used to enhance the effectiveness of PTX against this type of tumor.

Current strategies for different paclitaxel-loaded Nano-delivery Systems towards therapeutic applications for ovarian carcinoma: A review article

Ovarian carcinoma (OC) is one of the leading causes of death among gynecologic malignancies all over the world. It is characterized by high mortality rate because of the lack of early diagnosis. The first-line chemotherapeutic regimen for late stage epithelial ovarian cancer is paclitaxel in combination to carboplatin. However, in most of cases, relapse occurs within six months despite the initial success of this chemotherapeutic combination. A lot of challenges have been encountered with the conventional delivery of paclitaxel in addition to the occurrence of severe off-target toxicity. One major problem is poor paclitaxel solubility which was improved by addition of Cremophor EL that unfortunately resulted in hypersensitivity side effects. Another obstacle is the multi drug resistance which is the main cause of OC recurrence. Accordingly, incorporation of paclitaxel, solely or in combination to other drugs, in nanocarrier systems has grabbed attention of many researchers to circumvent all these hurdles. The current review is the first article that provides a comprehensive overview on multi-faceted implementations of paclitaxel loaded nanoplatforms to solve delivery obstacles of paclitaxel in management of ovarian carcinoma. Moreover, challenges in physicochemical properties, biological activity and targeted delivery of PTX were depicted with corresponding solutions using nanotechnology. Different categories of nanocarriers employed were collected included lipid, protein, polymeric, solid nanoemulsion and hybrid systems. Future perspectives including imperative research considerations in ovarian cancer therapy were proposed as well.

Treatment implications of natural compounds targeting lipid metabolism in nonalcoholic fatty liver disease, obesity and cancer

Metabolic disorders can lead to a scarcity or excess of certain metabolites such as glucose, lipids, proteins, purines, and metal ions, which provide the biochemical foundation and directly contribute to the etiology of metabolic diseases. Nonalcoholic fatty liver disease, obesity, and cancer are common metabolic disorders closely associated with abnormal lipid metabolism. In this review, we first describe the regulatory machinery of lipid metabolism and its deregulation in metabolic diseases. Next, we enumerate and integrate the mechanism of action of some natural compounds, including terpenoids and flavonoids, to ameliorate the development of metabolic diseases by targeting lipid metabolism. Medicinal natural products have an established history of use in health care and therapy. Natural compounds might provide a good source of potential therapeutic agents for treating or preventing metabolic diseases with lipid metabolic abnormalities.

Review for Analytical Methods for the Determination of Sodium Cephalothin

Infections are the second leading cause of global morbidity and mortality, therefore it is highly important to study the antimicrobial agents such as cephalosporins. Cephalothin, an antimicrobial agent that belongs to the class of cephalosporins, has bactericidal activity and it is widely used in the Brazilian health system. In literature, some analytical methods are found for the identification and quantification of this drug, which are essential for its quality control, which ensures maintaining the product characteristics, therapeutic efficacy and patient's safety. The aim of this article is to review the available information on analytical methods for cephalothin. Thus, this study presents a literature review on cephalothin and the analytical methods developed for the analysis of this drug in official and scientific papers. It is essential to note that most of the developed methods used toxic and hazardous solvents, which makes necessary industries and researchers choose to develop environmental-friendly techniques, which will contribute to the harmonization of science, human, and environmental health.

Tolerance, Variability and Pharmacokinetics of Albumin-Bound Paclitaxel in Chinese Breast Cancer Patients

Objective: The aim of this study was to explore the tolerance, variability, and pharmacokinetics (PK) of albumin-bound paclitaxel (QL, HR, ZDTQ) among Chinese breast cancer patients.

Methods: Three randomized, open-label, two-period crossover bioequivalence studies were conducted with albumin-bound paclitaxel. Each subject received a single dose of 260 mg/m² albumin-bound paclitaxel [sponsor 1 (QL, light food), sponsor 2 (HR, fasting), sponsor 3 (ZDTQ, light food); test] or Abraxane® (reference) and was monitored for 72 h. Serum concentrations of total paclitaxel and unbound paclitaxel were measured using liquid chromatography/mass spectrometry (LC/MS), and appropriate pharmacokinetic parameters were determined by non-compartmental methods. Safety assessments included adverse events, hematology and biochemistry tests.

Results: The bioequivalence analyses of the QL, HR, and ZDTQ products included 24, 23, and 24 patients, respectively. The mean t_1/2 was 20.61–27.31 h for total paclitaxel. Food intake did not affect the pharmacokinetics of paclitaxel. From the comparison of total paclitaxel and unbound paclitaxel, the 90% confidence intervals (CIs) for the ratios of C_max, AUC_0−t, and AUC_0−∞ were within 80.00–125.00%. The intra-subject variability ranged from 6.4–11% to 9.85–15.87% for total paclitaxel and unbound paclitaxel, respectively. Almost all subjects in the test and Abraxane® (reference) groups experienced mild or moderate adverse events. No fatal AEs or study drug injection site reactions related to these drugs were observed.

Conclusion: Albumin-bound paclitaxel (QL, HR or ZDTQ; test products) showed bioequivalence to Abraxane® (reference) with lower intra-subject variability, which was less than 16% in all cases, and was well-tolerated in Chinese breast cancer patients. Twenty-two patients are enough for an albumin-bound paclitaxel bioequivalence study.

Melatonin disturbs SUMOylation-mediated crosstalk between c-Myc and nestin via MT1 activation and promotes the sensitivity of paclitaxel in brain cancer stem cells

Here the underlying antitumor mechanism of melatonin and its potency as a sensitizer of paclitaxel was investigated in X02 cancer stem cells. Melatonin suppressed sphere formation and induced G2/M arrest in X02 cells expressing nestin, CD133, CXCR4, and SOX-2 as biomarkers of stemness. Furthermore, melatonin reduced the expression of CDK2, CDK4, cyclin D1, cyclin E, and c-Myc and upregulated cyclin B1 in X02 cells. Notably, genes of c-Myc related mRNAs were differentially expressed in melatonin-treated X02 cells by microarray analysis. Consistently, melatonin reduced the expression of c-Myc at mRNA and protein levels, which was blocked by MG132. Of note, overexpression of c-Myc increased the expression of nestin, while overexpression of nestin enhanced c-Myc through crosstalk despite different locations, nucleus, and cytoplasm. Interestingly, melatonin attenuated small ubiquitin-related modifier-1 (SUMO-1) more than SUMO-2 or SUMO-3 and disturbed nuclear translocation of nestin for direct binding to c-Myc by SUMOylation of SUMO-1 protein by immunofluorescence and immunoprecipitation. Also, melatonin reduced trimethylated histone H3K4me3 and H3K36me3 more than dimethylation in X02 cells by Western blotting and chromatin immunoprecipitation assay. Notably, melatonin upregulated MT1, not MT2, in X02 cells and melatonin receptor inhibitor luzindole blocked the ability of melatonin to decrease the expression of nestin, p-c-Myc(S62), and c-Myc. Furthermore, melatonin promoted cytotoxicity, sub-G1 accumulation, and apoptotic body formation by Paclitaxcel in X02 cells. Taken together, these findings suggest that melatonin inhibits stemness via suppression of c-Myc, nestin, and histone methylation via MT1 activation and promotes anticancer effect of Paclitaxcel in brain cancer stem cells.

A Review of Analytical Methods for p-Coumaric Acid in Plant-Based Products, Beverages, and Biological Matrices

p-Coumaric acid (p-CA), also known as 4-hydroxycinnamic acid, is a phenolic acid, which has been widely studied due to its beneficial effects against several diseases and its wide distribution in the plant kingdom. This phenolic compound can be found in the free form or conjugated with other molecules; therefore, its bioavailability and the pathways via which it is metabolized change according to its chemical structure. p-CA has potential pharmacological effects because it has high free radical scavenging, anti-inflammatory, antineoplastic, and antimicrobial activities, among other biological properties. It is therefore essential to choose the most appropriate and effective analytical method for qualitative and quantitative determination of p-CA in different matrices, such as plasma, urine, plant extracts, and drug delivery systems. The most-reported analytical method for this purpose is high-performance liquid chromatography, which is mostly coupled with some type of detectors, such as UV/Vis detector. However, other analytical techniques are also used to evaluate this compound. This review presents a summary of p-CA in terms of its chemical and pharmacokinetic properties, pharmacological effects, drug delivery systems, and the analytical methods described in the literature that are suitable for its quantification.