Paclitaxel: a review of adverse toxicities and novel delivery strategies

Novel poly(2-oxazoline) block copolymer with aromatic heterocyclic side chains as a drug delivery platform

Here we report a novel poly(2-oxazoline)-based block copolymer with the aromatic heterocyclic side chains in one block, poly(2-methyl-2-oxazoline)-b-poly(2-N,N-dimethyl-1,3,5-triazine-2,4-diamine-6-ethyl-2-oxazoline) (PMeOx-PcBOx), and demonstrate its potential application as a drug delivery platform. The copolymer was synthesized via the condensation of N,N-dimethylbiguanide with the methyl ester side chain in poly(2-methoxycarboxyethyl-2-oxazoline) block (PMestOx) of the PMeOx-PMestOx diblock copolymer. We confirmed the N,N-dimethylbiguanide condensation with PMestOx and the complete conversion of the side chain to the N,N-dimethyl-1,3,5-triazine-2,4-diamine-6-ethyl moiety by NMR spectroscopy, MALDI-TOF mass spectroscopy, UV-Vis spectroscopy, and titration analysis. The PMeOx-PcBOx copolymer self-assemble into polymeric micelles in aqueous solution. Successful encapsulation into these micelles has been demonstrated for 1) several poorly soluble drugs, such as bruceantin and LY2109761, and 2) dichloro(1,2-diaminocyclohexane)platinum(II) (DachPt). The first class of drugs is incorporated possibly via hydrogen bonding and pi-pi interactions with the PcBOx side groups, while the second one is likely forms coordination bonds with the same side groups. The capability of this new copolymer to solubilize a uniquely diverse set of active pharmaceutical ingredients suggests potential applications in drug delivery.

Co-delivery of paclitaxel and gemcitabine by methoxy poly(ethylene glycol)-poly(lactide-coglycolide)-polypeptide nanoparticles for effective breast cancer therapy

Traditional chemotherapeutic drugs have shown limited clinical curative effects in antitumor therapy. The application of multidrug combination and adjuvant-drug carriers is a feasible strategy to overcome the limitations while minimizing the dosage of single drug and acquiring the synergistic effects in tumor therapy. However, the systemic toxicity, drug resistance, and tumor recurrence are still unavoidable. Here we develop core-shell nanoparticles (NPs) to encapsulate paclitaxel (PTX) and gemcitabine (GEM) for breast cancer therapy. We find that the NPs could encapsulate PTX and GEM, with an encapsulation efficiency of 96.3 and 95.13%, respectively. Moreover, the drug loading of these NPs is 2.71% (PTX) and 2.64% (GEM). Notably, the co-delivery of GEM and PTX performs enhanced anticancer effect compared with the PTX alone or GEM alone therapy at the same concentration, which indicates a synergistic effect. Moreover, encapsulation of PTX and GEM by methoxy poly(ethylene glycol)-poly(lactide-coglycolide) also shows enhanced anticancer effects (81.5% tumor inhibition) and reduced systemic toxicity in vivo compared with free drugs (65% tumor inhibition). Together with those results, co-delivery of PTX and GEM by methoxy poly(ethylene glycol)-poly(lactide-coglycolide) might have important potencies in clinical applications for breast cancer therapy.

Enhanced anti-tumor efficacy and safety with metronomic intraperitoneal chemotherapy for metastatic ovarian cancer using biodegradable nanotextile implants

The objective of this study was to evaluate intraperitoneal (IP) metronomic chemotherapy using sustained release paclitaxel (PTX) delivery from electrospun biodegradable polymeric yarns woven into suturable nanotextiles. Following confirmation of in vitro PTX efficacy in ID8-VEGF epithelial ovarian cancer cells, in vivo studies were performed upon surgical peritoneal implantation of nanotextile implants in orthotopic, syngeneic ID8-VEGF tumor-bearing C57BL/6 mice. In comparison to the clinical PTX-solution, there was a significant enhancement of anti-tumor efficacy and safety with PTX-nanotextiles. After 35-days, the peritoneum of tumor-bearing mice with PTX-nanotextiles was completely devoid of tumor nodules and ascitic fluid. Additionally, VEGF levels measured in peritoneal lavage fluid were 300-fold lower compared to PTX-solution and 600-fold lower as compared to untreated tumor-bearing animals. PTX-solution treated group also developed severe metastatic lesions and progressive ascitic fluid buildup. More importantly, no signs of systemic/ organ toxicity were observed in PTX-nanotextile implanted mice, unlike the systemic toxic effects induced by PTX-solution. Collectively, our results show the therapeutic and safety advantages offered by combining clinically translatable metronomic low-dose chemotherapy and IP pharmacokinetics using biodegradable nanotextile implants in addressing the challenges of late-stage ovarian cancer.

[Preparation and characterization of paclitaxel microspheres in situ gel and its antitumor efficacy by local injection]

OBJECTIVE

The current difficulties in the treatment of tumor include repeated administration and high recurrence rate after tumor resection. In order to reduce the number of doses, avoid side effects of chemotherapeutic drugs, suppress tumor growth and delay tumor recurrence after surgery, a temperature-sensitive in situ gel with paclitaxel microspheres (PTX/M gel) was prepared. PTX/M gel was administered by intratumoral injection once a month.

METHODS

First of all, paclitaxel microspheres (PTX/M) were prepared by emulsion solvent evaporation method. A laser particle size distribution analyzer was used to investigate the size, distribution, specific surface area of microspheres. Paclitaxel content was determined by high performance liquid chromatography (HPLC). Then encapsulation efficiency of paclitaxel was calculated and in vitro release characteristics were studied. Secondly, PTX/M gel was prepared by cold dissolution method. The phase transition temperature, elastic modulus, dissolution curve, correlation between dissolution and release were measured. Finally, U87 MG and 4T1 subcutaneous tumor models were established respectively to study the efficacy of PTX/M gel in suppressing tumor growth and delaying tumor recurrence after surgery.

RESULTS

The median diameter of the selected PTX/M was (32.24±1.09) μm, the specific surface area was (206.61±10.23) m²/kg, the encapsulation efficiency was 85.29%±1.34%, and the cumulative release percentage of paclitaxel from PTX/M was 33.56%±3.33% in one month. Phase transition temperature of PTX/M gel was 33 °C. The elastic modulus of PTX/M gel at 25 °C and 37 °C were 4.2×103 Pa and 18×103 Pa, respectively. The gel could stay in the body for up to 48 hours. It could be seen from the results of animal experiments that were compared with the saline group and the Taxol group, and the tumor-bearing mice of the PTX/M gel group had the slowest tumor growth (P<0.05). Similarly, in the tumor recurrence experiments, the mice of PTX/M gel group had the latest tumor recurrence after surgery.

CONCLUSION

As a local sustained-release preparation, PTX/M gel can effectively suppress tumor growth and delay postoperative recurrence of tumors. It has potential advantages in tumor treatment.

Paclitaxel-Coated Balloons and Eluting Stents: Is There a Mortality Risk in Patients With Peripheral Artery Disease?

Paclitaxel drug-coated balloons and drug-eluting stents became commercially available for the treatment of intermittent claudication in 2015 and 2012, respectively. Both devices demonstrated superiority in limb revascularization compared with non-paclitaxel-coated devices and were rapidly accepted into clinical practice. In a recent systematic review and study-level meta-analysis, Katsanos et al reported a late all-cause mortality signal for patients in the drug-coated balloon and drug-eluting stent arms of randomized clinical trials for both devices. As a result of this safety signal, Vascular InterVentional Advances Physicians (VIVA), a not-for-profit 501c(3) organization, convened the Vascular Leaders Forum on March 1 and 2, 2019, in Washington, DC, to initiate an open and collaborative process of investigation into this finding. The Vascular Leaders Forum brought together 100 stakeholders, including an international group of representatives of cardiovascular medicine, interventional radiology, vascular medicine, and vascular surgery; oncologists; basic scientists; the Food and Drug Administration; the Centers for Medicare and Medicaid Services; and commercial manufacturers of these products. The Vascular Leaders Forum reviewed the natural history of peripheral arterial disease, the use of paclitaxel in peripheral arterial disease and other conditions, the harm signal noted by Katsanos et al, the impact of the methods chosen by Katsanos et al, possible mechanisms of harm, the role of the Food and Drug Administration in a setting like this one, and guidance for clinicians taking care of patients with symptomatic peripheral arterial disease. This document integrates the most current data to help establish an appropriate path forward to understand the risks and benefits associated with these technologies while ensuring the best treatment paradigm for patients.

Dietary baker's yeast sensitizes Ehrlich mammary adenocarcinoma to paclitaxel in mice bearing tumor

Baker's yeast, Saccharomyces cerevisiae, has been shown to sensitize a variety of breast cancer cell (BCC) lines to paclitaxel chemotherapy in vitro. The present study evaluated the ability of S. cerevisiae to sensitize BCCs to paclitaxel in animals bearing Ehrlich ascites carcinoma (EAC). Mice bearing EAC were intratumorally injected with dead S. cerevisiae (1x107 cells/ml) in the presence or absence of low- and high-dose paclitaxel [paclitaxel-L, 2 mg/kg body weight (BW) and paclitaxel-H, 10 mg/kg BW, respectively]. At 30 days post tumor inoculation, co-treatment with yeast plus paclitaxel-L showed improvements over paclitaxel-H alone, as measured by tumor weight (-64 vs. -53%), DNA damage (+79 vs. +62%), tumor cell apoptosis (+217 vs. +177%), cell proliferation (-56 vs. -42%) and Ki-67 marker (+95 vs. +40%). Histopathology and ultra-structural examinations showed that yeast plus paclitaxel-L enhanced apoptosis in EAC more than paclitaxel-H alone and caused comparable tumor necrosis. We conclude that baker's yeast may be used with low-dose chemotherapy to achieve the same potency as high-dose chemotherapy in mice bearing EAC. This suggests that baker's yeast may be an anticancer adjuvant and may have clinical implications for the treatment of breast cancer.

Promises of Nanotherapeutics in Obesity

The application of nanotechnology to medicine promises a wide range of new tools and possibilities, from earlier diagnostics and improved imaging, to better, more efficient, and more targeted therapies. This emerging field could help address obesity, with advances in drug delivery, nutraceuticals, and genetic and epigenetic therapeutics. Its application to obesity is still largely in the development phase. Here, we review the novel angle of nanotech applied to human consumable products and their specific applications to addressing obesity through nutraceuticals, with respect to benefits and limitations of current nanotechnology methods. Further, we review potential future applications to deliver genetic and epigenetic miRNA therapeutics. Finally, we discuss future directions, including theranostics, combinatory therapy, and personalized medicine.

A Review of Self-Expanding Esophageal Stents for the Palliation Therapy of Inoperable Esophageal Malignancies

Esophageal cancer is a very deadly disease, killing more than 15,000 people in the United States annually. Almost 400,000 new cases happen in the worldwide every year. More than 50% esophageal cancer patients are diagnosed at an advanced stage when they need an esophageal stent to open the blocked esophagus for feeding and drinking. Esophageal stents have evolved in stages over the years. Current clinically used stents commonly include stainless steel or nitinol self-expandable metallic stent (SEMS) and self-expandable plastic stent (SEPS). There are many choices of different types of stents and sizes, with fierce competition among manufacturers. However, current stent technology, whether uncovered, partially covered, fully covered SEMS or SEPS, has their own advantages to solve the dysphagia, stricture, and fistula problems, but they also cause some clinical complications. The ideal stent remains elusive. New 3D printing technique may bring new promising potential to manufacturing personalized esophageal stents. Drug-eluting stents could be the new avenue to do more than just pry open a stricture or cover a defect in the esophageal lumen, a possibility of proving local anticancer therapy simultaneously. Additionally, the lack of esophageal cancer animal models also hinders the progress of stent development. This paper reviews these topics for a comprehensive understanding of this field. In a conclusion, the ultimate goal of the future esophageal stent would have multifunction to treat the underlying conditions and restore esophageal function to near normal.

Augmented cytotoxic effects of paclitaxel by curcumin induced overexpression of folate receptor-α for enhanced targeted drug delivery in HeLa cells

BACKGROUND

New targeted therapies are intended to minimize the toxic effects and maximize destruction of tumor cells. Folate is a membrane-bound receptor that plays a vital role in the uptake of anti-folate molecules aimed for efficient drug delivery of anti-folate drugs.

PURPOSE

The present study is aimed at the modulation of the expression of folate receptor by curcumin that enhances the intake, cytotoxicity and anticancer effects of paclitaxel in HeLa cells.

MATERIALS AND METHODS

HeLa cells were pretreated with curcumin and treated with paclitaxel. We measured the cell viability, uptake of radiolabelled folic acid and paclitaxel, Folate receptor -alpha (FR-α) protein expression by immunocytochemistry and western blot and FR-α mRNA expression by qualitative and quantitative analysis.

RESULTS

This study shows that curcumin (10 - 50 µM) causes significantly increased cytotoxicity in a dose and time dependent manner. It also enhances the intake of radiolabeled folic acid and paclitaxel 3-4 folds in HeLa cells. The pretreatment of HeLa cells with curcumin shows statistically significant of cell death by paclitaxel. The quantitative RT-PCR demonstrates the expression of FR- α mRNA upon curcumin treatment. Furthermore, immunochemistry and western blotting analysis proved that curcumin enhances expression the FR- α in HeLa cells.

CONCLUSION

Our study proved that the molecular mechanism of curcumin enhances the upregulation of FR - α mRNA and protein expression in HeLa cells. Therefore, a combination of curcumin and paclitaxel at less concentration may be a targeting strategy for FR-targeted drug delivery providing a better therapeutic intervention of cancer.

Curcumin potentiates the antitumor activity of Paclitaxel in rat glioma C6 cells

BACKGROUND

Glioma is the most common primary cancer in central nervous system, especially in brain. Paclitaxel (PTX) is a microtubule stabilizing agent with anticancer potential, but its clinical application to brain tumours is limited by drug resistance, side effects, and lower brain penetration.

PURPOSE

Herein we explored the in vitro effects, in glioma C6 cells, of the combination of PTX with curcumin, a natural compound with chemotherapeutic activity, in order to improve cytotoxic effects and overcome PTX limitations.

RESULTS

Our data confirmed PTX antiproliferative activity that was improved by curcumin. These effects were confirmed by clonogenic assay and G0/G1 cell cycle arrest. PTX significantly promoted generation of intracellular reactive species (RS), while curcumin did not affect RS production; the combination of the two drugs resulted in a slight but significant increase in RS levels. Furthermore, we found a constitutive activation of NF-κB in C6 cell line that was inhibited by PTX and curcumin. Interestingly, combination of the drugs totally inhibited NF-κB nuclear translocation and reduced IκB phosphorylation. Our results also supported the involvement of p53-p21 axis in the anticancer effects of curcumin and PTX. The combination of the two drugs further increased p53 and p21 levels enhancing the antiproliferative effects. Furthermore, PTX plus curcumin most impressively activated caspase-3, effector of apoptosis pathways, and reduced the expression of the anti-apoptotic protein Bcl-2.

CONCLUSION

In conclusion, our findings demonstrated that combination of PTX and curcumin exerts a potentiated anti-glioma efficacy in vitro that may help in reducing dosage and/or minimizing side effects of cytotoxic therapy.

Paclitaxel Enhances the Innate Immunity by Promoting NLRP3 Inflammasome Activation in Macrophages

Microtubules play critical roles in regulating the activation of NLRP3 inflammasome and microtubule-destabilizing agents such as colchicine have been shown to suppress the activation of this inflammasome. However, it remains largely unknown whether paclitaxel, a microtubule-stabilizing agent being used in cancer therapy, has any influences on NLRP3 inflammasome activation. Here we showed that paclitaxel pre-treatment greatly enhanced ATP- or nigericin-induced NLRP3 inflammasome activation as indicated by increased release of cleaved caspase-1 and mature IL-1β, enhanced formation of ASC speck, and increased gasdermin D cleavage and pyroptosis. Paclitaxel time- and dose-dependently induced α-tubulin acetylation in LPS-primed murine and human macrophages and further increased ATP- or nigericin-induced α-tubulin acetylation. Such increased α-tubulin acetylation was significantly suppressed either by resveratrol or NAD⁺ (coenzyme required for deacetylase activity of SIRT2), or by genetic knockdown of MEC-17 (gene encoding α-tubulin acetyltransferase 1). Concurrently, the paclitaxel-mediated enhancement of NLRP3 inflammasome activation was significantly suppressed by resveratrol, NAD⁺, or MEC-17 knockdown, indicating the involvement of paclitaxel-induced α-tubulin acetylation in the augmentation of NLRP3 inflammasome activation. Similar to paclitaxel, epothilone B that is another microtubule-stabilizing agent also induced α-tubulin acetylation and increased NLRP3 inflammasome activation in macrophages in response to ATP treatment. Consistent with the in vitro results, intraperitoneal administration of paclitaxel significantly increased serum IL-1β levels, reduced bacterial burden, dampened infiltration of inflammatory cells in the liver, and improved animal survival in a mouse model of bacterial infection. Collectively, our data indicate that paclitaxel potentiated NLRP3 inflammasome activation by inducing α-tubulin acetylation and thereby conferred enhanced antibacterial innate responses, suggesting its potential application against pathogenic infections beyond its use as a chemotherapeutic agent.

Drug-eluting balloon angioplasty versus uncoated balloon angioplasty for the treatment of in-stent restenosis of the femoropopliteal arteries

BACKGROUND

Stents are placed in the femoropopliteal arteries for numerous reasons, such as atherosclerotic disease, the need for dissection, and perforation of the arteries, and can become stenosed with the passage of time. When a stent develops a flow-limiting stenosis, this process is known as "in-stent stenosis." It is thought that in-stent restenosis is caused by a process known as "intimal hyperplasia" rather than by the progression of atherosclerotic disease. Management of in-stent restenosis may include performing balloon angioplasty, deploying another stent within the stenosed stent to force it open, and creating a bypass to deliver blood around the stent. The role of drug-eluting technologies, such as drug-eluting balloons (DEBs), in the management of in-stent restenosis is unclear. Drug-eluting balloons might function by coating the inside of stenosed stents with cytotoxic chemicals such as paclitaxel and by inhibiting the hyperplastic processes responsible for in-stent restenosis. It is important to perform this systematic review to evaluate the efficacy of DEB because of the potential for increased expenses associated with DEBs over uncoated balloon angioplasty, also known as plain old balloon angioplasty (POBA).

OBJECTIVES

To assess the safety and efficacy of DEBs compared with uncoated balloon angioplasty in people with in-stent restenosis of the femoropopliteal arteries as assessed by criteria such as amputation-free survival, vessel patency, target lesion revascularization, binary restenosis rate, and death. We define "in-stent restenosis" as 50% or greater narrowing of a previously stented vessel by duplex ultrasound or angiography.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL databases and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to November 28, 2017. Review authors also undertook reference checking to identify additional studies.

SELECTION CRITERIA

We included all randomized controlled trials that compared DEBs versus uncoated balloon angioplasty for treatment of in-stent restenosis in the femoropopliteal arteries.

DATA COLLECTION AND ANALYSIS

Two review authors (AK, WA) independently selected appropriate trials and performed data extraction, assessment of trial quality, and data analysis. The senior review author (AD) adjudicated any disagreements.

MAIN RESULTS

Three trials that randomized a combined total of 263 participants met the review inclusion criteria. All three trials examined the treatment of symptomatic in-stent restenosis within the femoropopliteal arteries. These trials were carried out in Germany and Austria and used paclitaxel as the agent in the drug-eluting balloons. Two of the three trials were industry sponsored. Two companies manufactured the drug-eluting balloons (Eurocor, Bonn, Germany; Medtronic, Fridley, Minnesota, USA). The trials examined both anatomical and clinical endpoints. We noted heterogeneity in the frequency of bailout stenting deployment between studies as well as in the dosage of paclitaxel applied by the DEBs. Using GRADE assessment criteria, we determined that the certainty of evidence presented was very low for the outcomes of amputation, target lesion revascularization, binary restenosis, death, and improvement of one or more Rutherford categories. Most participants were followed up to 12 months, but one trial followed participants for up to 24 months.Trial results show no difference in the incidence of amputation between DEBs and uncoated balloon angioplasty. DEBs showed better outcomes for up to 24 months for target lesion revascularization (odds ratio (OR) 0.05, 95% confidence Interval (CI) 0.00 to 0.92 at six months; OR 0.24, 95% CI 0.08 to 0.70 at 24 months) and at six and 12 months for binary restenosis (OR 0.28, 95% CI 0.14 to 0.56 at six months; OR 0.34, 95% CI 0.15 to 0.76 at 12 months). Participants treated with DEBs also showed improvement of one or more Rutherford categories at six and 12 months (OR 1.81, 95% CI 1.02 to 3.21 at six months; OR 2.08, 95% CI 1.13 to 3.83 at 12 months). Data show no clear differences in death between DEBs and uncoated balloon angioplasty. Data were insufficient for subgroup or sensitivity analyses to be conducted.

AUTHORS' CONCLUSIONS

Based on a meta-analysis of three trials with 263 participants, evidence suggests an advantage for DEBs compared with uncoated balloon angioplasty for anatomical endpoints such as target lesion revascularization (TLR) and binary restenosis, and for one clinical endpoint - improvement in Rutherford category post intervention for up to 24 months. However, the certainty of evidence for all these outcomes is very low due to the small number of included studies and participants and the high risk of bias in study design. Adequately powered and carefully constructed randomized controlled trials are needed to adequately investigate the role of drug-eluting technologies in the management of in-stent restenosis.

Role of Muscarinic Acetylcholine Receptors in Breast Cancer: Design of Metronomic Chemotherapy

BACKGROUND

muscarinic acetylcholine receptors (mAChRs) have attracted interest as targets for therapeutic interventions in different illnesses like Alzheimer´s disease, viral infections and different tumors. Regarding the latter, many authors have studied each subtype of mAChRs, which seem to be involved in the progression of distinct types of malignancies.

METHODS

We carefully revised research literature focused on mAChRs expression and signaling as well as in their involvement in cancer progression and treatment. The characteristics of screened papers were described using the mentioned conceptual framework.

RESULTS

Muscarinic antagonists and agonists have been assayed for the treatment of tumors established in lung, brain and breast with beneficial effects. We described an up-regulation of mAChRs in mammary tumors and the lack of expression in non-tumorigenic breast cells and normal mammary tissues. We and others demonstrated that muscarinic agonists can trigger anti-tumor actions in a dose-dependent manner on tumors originated in different organs like brain or breast. At pharmacological concentrations, they exert similar effects to traditional chemotherapeutic agents. Metronomic chemotherapy refers to the administration of anti-cancer drugs at low doses with short intervals among them, and it is a different regimen applied in cancer treatment reducing malignant growth and angiogenesis, and very low incidence of adverse effects.

CONCLUSION

The usage of subthreshold concentrations of muscarinic agonists combined with conventional chemotherapeutic agents could be a promising tool for breast cancer therapy.

Targeted Delivery of Bioactive Molecules for Vascular Intervention and Tissue Engineering

Cardiovascular diseases are the leading cause of death in the United States. Treatment often requires surgical interventions to re-open occluded vessels, bypass severe occlusions, or stabilize aneurysms. Despite the short-term success of such interventions, many ultimately fail due to thrombosis or restenosis (following stent placement), or incomplete healing (such as after aneurysm coil placement). Bioactive molecules capable of modulating host tissue responses and preventing these complications have been identified, but systemic delivery is often harmful or ineffective. This review discusses the use of localized bioactive molecule delivery methods to enhance the long-term success of vascular interventions, such as drug-eluting stents and aneurysm coils, as well as nanoparticles for targeted molecule delivery. Vascular grafts in particular have poor patency in small diameter, high flow applications, such as coronary artery bypass grafting (CABG). Grafts fabricated from a variety of approaches may benefit from bioactive molecule incorporation to improve patency. Tissue engineering is an especially promising approach for vascular graft fabrication that may be conducive to incorporation of drugs or growth factors. Overall, localized and targeted delivery of bioactive molecules has shown promise for improving the outcomes of vascular interventions, with technologies such as drug-eluting stents showing excellent clinical success. However, many targeted vascular drug delivery systems have yet to reach the clinic. There is still a need to better optimize bioactive molecule release kinetics and identify synergistic biomolecule combinations before the clinical impact of these technologies can be realized.

Carboplatin–Angelica gigas Nakai combination synergistically enhances apoptosis by suppressed Akt, Erk, and Stat3 expression in H460 human lung cancer cells

The lower potency of low dose of carboplatin often requires combination with other drugs to improve its efficacy. Newer and more potent carboplatin-based combination therapies are investigated for treatment. We investigated whether paclitaxel, carboplatin, and Angelica gigas Nakai (AGN) affect viability of H460 cells by MTT assay. Western blot analysis was used to measure the expression of various modulators, such as p-Stat3, p-Akt, and p-Erk. Paclitaxel, carboplatin, and AGN affected the viability of H460 cells. Paclitaxel, carboplatin, and AGN suppressed p-Akt, p-Erk, and p-Stat3 expression. AGN combined with carboplatin significantly decreased c-Jun, HIF-1α, and VEGF levels. AGN combined with carboplatin significantly increased p21 and p27 levels and suppressed cyclin D1 and cyclin E levels. AGN combined with carboplatin-induced apoptosis by increasing Bax and cleavage of caspase and Parp level and by suppressing Bcl-2 level. Our results clearly demonstrate that AGN combined with carboplatin could be a useful compound for treating lung cancer.

Recent Fragmentation May Not Alter Genetic Patterns in Endangered Long-Lived Species: Evidence From Taxus cuspidata

Forestland fragmentation caused by overexploitation of forest resources can in principle reduce genetic diversity, limit gene flow and eventually lead to species developing strong genetic structure. However, the genetic consequences of recent anthropogenic fragmentation of tree species remain unclear. Taxus cuspidata, which has extremely small populations distributed mainly in Changbai Mt. in Northeast (NE) China, has recently endured severe habitat fragmentation. Here, we investigate the pattern of genetic diversity and structure, identify risk factors, predict the future distribution and finally provide guidelines for the conservation and management of this species. We used three chloroplast and two mitochondrial DNA fragments, which are both paternally inherited in yews but differ in mutation rates, to genotype a total of 265 individuals from 26 populations covering the distribution of the species in China. Both chloroplast and mitochondrial data showed high degrees of genetic diversity, extensive gene flow over the entire geographical range and historical stability of both effective population size and distribution of the species. However, ecological niche modeling suggests a decrease in suitable areas for this species by the years 2050 and 2070. The maintenance of high genetic diversity and the existence of sufficient gene flow suggest that recent fragmentation has not affected the genetic composition of the long-lived tree T. cuspidata. However, severe impacts of anthropogenic activities are already threatening the species. Conservation and management strategies should be implemented in order to protect the remnant populations.

A New Approach for Loading Anticancer Drugs Into Mesenchymal Stem Cell-Derived Exosome Mimetics for Cancer Therapy

Exosomes derived from mesenchymal stem cells (MSCs) have been evaluated for their potential to be used as drug delivery vehicles. Synthetically personalized exosome mimetics (EMs) could be the alternative vesicles for drug delivery. In this study, we aimed to isolate EMs from human MSCs. Cells were mixed with paclitaxel (PTX) and PTX-loaded EMs (PTX-MSC-EMs) were isolated and evaluated for their anticancer effects against breast cancer. EMs were isolated from human bone marrow-derived MSCs. MSCs (4 × 106 cells/mL) were mixed with or without PTX at different concentrations in phosphate-buffered saline (PBS) and serially extruded through 10-, 5-, and 1-μm polycarbonate membrane filters using a mini-extruder. MSCs were centrifuged to remove debris and the supernatant was filtered through a 0.22-μm filter, followed by ultracentrifugation to isolate EMs and drug-loaded EMs. EMs without encapsulated drug (MSC-EMs) and those with encapsulated PTX (PTX-MSC-EMs) were characterized by western blotting, nanoparticle tracking analysis (NTA), and transmission electron microscopy (TEM). The anticancer effects of MSC-EMs and PTX-MSC-EMs were assessed with breast cancer (MDA-MB-231) cells both in vitro and in vivo using optical imaging. EMs were isolated by the extrusion method and ultracentrifugation. The isolated vesicles were positive for membrane markers (ALIX and CD63) and negative for golgi (GM130) and endoplasmic (calnexin) marker proteins. NTA revealed the size of MSC-EM to be around 149 nm, while TEM confirmed its morphology. PTX-MSC-EMs significantly (p < 0.05) decreased the viability of MDA-MB-231 cells in vitro at increasing concentrations of EM. The in vivo tumor growth was significantly inhibited by PTX-MSC-EMs as compared to control and/or MSC-EMs. Thus, MSC-EMs were successfully isolated using simple procedures and drug-loaded MSC-EMs were shown to be therapeutically efficient for the treatment of breast cancer both in vitro and in vivo. MSC-EMs may be used as drug delivery vehicles for breast cancers.

Different Nanoformulations Alter the Tissue Distribution of Paclitaxel, Which Aligns with Reported Distinct Efficacy and Safety Profiles

Previous studies have shown that different paclitaxel formulations produce distinct anticancer efficacy and safety profiles in animals and humans. This study aimed to investigate the distinct pharmacokinetics and tissue distribution of various nanoformulations of paclitaxel, which may translate into potential differences in safety and efficacy. Four nanoparticle formulations ( nab-paclitaxel, mouse albumin nab-paclitaxel [m -nab-paclitaxel], micellar paclitaxel, and polymeric nanoparticle paclitaxel) as well as solvent-based paclitaxel were intravenously administered to mice. Seventeen blood and tissue samples were collected at different time points. The total paclitaxel concentration in each tissue specimen was measured with liquid chromatography-tandem mass spectrometry. Compared with solvent-based paclitaxel, all four nanoformulations demonstrated decreased paclitaxel exposure in plasma. All nanoformulations were associated with paclitaxel blood-cell accumulation in mice; however, m- nab-paclitaxel was associated with the lowest accumulation. Five minutes after dosing, the total paclitaxel in the tissues and blood was approximately 44% to 57% of the administered dose of all paclitaxel formulations. Paclitaxel was primarily distributed to liver, muscle, intestine, kidney, skin, and bone. Compared with solvent-based paclitaxel, the different nanocarriers altered the distribution of paclitaxel in all tissues with distinct paclitaxel concentration-time profiles. nab-paclitaxel was associated with increased delivery efficiency of paclitaxel in the pancreas compared with the other formulations, consistent with the demonstrated efficacy of nab-paclitaxel in pancreatic cancer. All the nanoformulations led to high penetration in the lungs and fat pad, which potentially points to efficacy in lung and breast cancers. Micellar paclitaxel and polymeric nanoparticle paclitaxel were associated with high paclitaxel accumulation in the heart; thus, the risk of cardiovascular toxicity with these formulations may warrant further investigation. The solvent-based formulation was associated with the poorest paclitaxel penetration in all tissues and the lowest tissue-to-plasma ratio. The different nanocarriers of paclitaxel were associated with distinct pharmacokinetics and tissue distribution, which largely align with the observed efficacy and toxicity profiles in clinical trials.

Spherical Nucleic Acid Nanoparticles: Therapeutic Potential

Spherical nucleic acids (SNAs) are highly oriented, well organized, polyvalent structures of nucleic acids conjugated to hollow or solid core nanoparticles. Because they can transfect many tissue and cell types without toxicity, induce minimum immune response, and penetrate various biological barriers (such as the skin, blood-brain barrier, and blood-tumor barrier), they have become versatile tools for the delivery of nucleic acids, drugs, and proteins for various therapeutic purposes. This article describes the unique structures and properties of SNAs and discusses how these properties enable their application in gene regulation, immunomodulation, and drug and protein delivery. It also summarizes current efforts towards clinical translation of SNAs and provides an expert opinion on remaining challenges to be addressed in the path forward to the clinic.

FORWARD I: a Phase III study of mirvetuximab soravtansine versus chemotherapy in platinum-resistant ovarian cancer

Mirvetuximab soravtansine, an antibody–drug conjugate that binds with high affinity to folate receptor-α to provide tumor-directed delivery of the potent microtubule-disrupting agent DM4, has emerged as a promising investigational agent for the treatment of ovarian cancer, particularly in the setting of platinum-resistant disease. Here we describe the rationale and design of FORWARD I (NCT02631876), the first randomized, multicenter Phase III study to compare the safety and efficacy of mirvetuximab soravtansine versus investigator's choice of chemotherapy in women with folate receptor-α-positive, platinum-resistant epithelial ovarian, primary peritoneal or fallopian tube cancer. Patients will be randomized in a 2:1 ratio. The primary end point is progression-free survival, and key secondary objectives include comparison of overall response rates, overall survival and duration of response.

Nitroxide radical-containing nanoparticles attenuate tumorigenic potential of triple negative breast cancer

The critical importance of reactive oxygen species (ROS) as oncogene activators and essential secondary messengers in cancer cell survival have been widely reported. Since oxidative stress has been implicated as being pivotal in various cancers, antioxidant therapy seems an apt strategy to abrogate ROS-mediated cellular processes to attenuate cancers. We therefore synthesized ROS scavenging nitroxide radical-containing nanoparticles (RNPs); pH insensitive RNP^O and pH sensitive RNP^N, to impede the proliferative and metastatic characteristics of the triple negative breast cancer cell line, MDA-MB-231, both in vitro and in vivo. RNPs significantly curtailed the proliferative and clonogenic potential of MDA-MB-231 and MCF-7 cell lines. Inhibition of ROS-mediated migratory and invasive characteristics of MDA-MB-231, via down regulation of NF-κB and MMP-2, was also confirmed. Furthermore, a significant anti-tumor and anti-metastatic potential of RNPs was observed in an MDA-MB-231 mouse xenograft model. Such tumoricidal effects of RNPs were attained with negligible adverse effects, compared to conventional low molecular weight antioxidants, TEMPOL. Thus, the tumoricidal effects of RNPs are suggestive of insights on precedence of nanoparticle-based therapeutics over current low molecular weight antioxidants to curtail ROS-induced tumorigenesis of various cancers.

Drug delivery challenges and future of chemotherapeutic nanomedicine for glioblastoma treatment

Glioblastoma (GBM) is one of the most aggressive and deadliest central nervous system tumors, and the current standard treatment is surgery followed by radiotherapy with concurrent chemotherapy. Nevertheless, the survival period is notably low. Although ample research has been performed to develop an effective therapeutic strategy for treating GBM, the success of extending patients' survival period and quality of life is limited. This review focuses on the strategies developed to address the challenges associated with drug delivery in GBM, particularly nanomedicine. The first part describes major obstacles to the development of effective GBM treatment strategies. The second part focuses on the conventional chemotherapeutic nanomedicine strategies, their limitations and the novel and advanced strategies of nanomedicine, which could be promising for GBM treatment. We also highlighted the prominence of nanomedicine clinical translation. The near future looks bright following the beginning of clinical translation of nanochemotherapy for GBM.

Enzyme-MOF Nanoreactor Activates Nontoxic Paracetamol for Cancer Therapy

Prodrug activation, by exogenously administered enzymes, for cancer therapy is an approach to achieve better selectivity and less systemic toxicity than conventional chemotherapy. However, the short half-lives of the activating enzymes in the bloodstream has limited its success. Demonstrated here is that a tyrosinase-MOF nanoreactor activates the prodrug paracetamol in cancer cells in a long-lasting manner. By generating reactive oxygen species (ROS) and depleting glutathione (GSH), the product of the enzymatic conversion of paracetamol is toxic to drug-resistant cancer cells. Tyrosinase-MOF nanoreactors cause significant cell death in the presence of paracetamol for up to three days after being internalized by cells, while free enzymes totally lose activity in a few hours. Thus, enzyme-MOF nanocomposites are envisioned to be novel persistent platforms for various biomedical applications.

Paclitaxel controlled delivery using a pH-responsive functional-AuNP/block-copolymer vesicular nanocarrier composite system

Paclitaxel (PTX)-loaded gold nanoparticles functionalized with mercaptooctanoic acid (MOA) and folic acid (FA) (AuMOA-FA) were encapsulated within pH-sensitive poly(2-vinylpyridine)-b-poly(ethylene oxide) (P2VP-PEO) vesicles with the aim to develop a more selective injectable nano-formulation for PTX, lacking the side effects of the conventional PTX delivery system. The size of the resulting composite vesicles was lower than 200 nm, i.e. it is suitable for tumor targeting applications taking advantage of the enhanced permeability and retention (EPR) effect. The vesicles did not aggregate in the presence of high electrolyte concentrations, indicating the colloidal stability of the vesicles. The vesicles did not leak their AuMOA-FA or PTX content at physiological pH of 7.4. However, AuMOA-FA and PTX release were significantly accelerated at acidic pHs resembling tumor environment and acidic intracellular compartments. PTX release from the vesicles at acidic pH apparently follows AuMOA-FA release from the vesicles. Flow cytometry measurements and confocal laser scanning microscopy images showed that the vesicles could enter A549 cancer cells in culture and that cellular uptake increased with time. Blank vesicles did not exhibit cytotoxicity and did not induce apoptosis in A549 cancer cells. The PTX currying vesicles exhibited comparable or a little higher cytotoxicity than free PTX. Both the PTX currying vesicles and free PTX induced A549 cells apoptosis, however the vesicle-encapsulated PTX induced a higher percentage of late apoptotic cells than free PTX.

Genotoxicity assessment of a selected cytostatic drug mixture in human lymphocytes: A study based on concentrations relevant for occupational exposure

Cytostatic drugs are highly cytotoxic agents used in cancer treatment and although their benefit is unquestionable, they have been recognized as hazardous to healthcare professionals in occupational settings. In a working environment, simultaneous exposure to cytostatics may occur creating a higher risk than that of a single substance. Hence, the present study evaluated the combined cyto/genotoxicity of a mixture of selected cytostatics with different mechanisms of action (MoA; 5-fluorouracil, cyclophosphamide and paclitaxel) towards human lymphocytes in vitro at a concentration range relevant for occupational as well as environmental exposure. The results suggest that the selected cytostatic drug mixture is potentially cyto/genotoxic and that it can induce cell and genome damage even at low concentrations. This indicates not only that such mixture may pose a risk to cell and genome integrity, but also that single compound toxicity data are not sufficient for the prediction of toxicity in a complex working environment. The presence of drugs in different amounts and with different MoA suggests the need to study the relationship between the presence of genotoxic components in the mixture and the resulting effects, taking into account the MoA of each component by itself. Therefore, this study provides new data sets necessary for scientifically-based risk assessments of cytostatic drug mixtures in occupational as well as environmental settings.

Novel anti-cancer drug COTI-2 synergizes with therapeutic agents and does not induce resistance or exhibit cross-resistance in human cancer cell lines

Emerging drug-resistance and drug-associated toxicities are two major factors limiting successful cancer therapy. Combinations of chemotherapeutic drugs have been used in the clinic to improve patient outcome. However, cancer cells can acquire resistance to drugs, alone or in combination. Resistant tumors can also exhibit cross-resistance to other chemotherapeutic agents, resulting in sub-optimal treatment and/or treatment failure. Therefore, developing novel oncology drugs that induce no or little acquired resistance and with a favorable safety profile is essential. We show here that combining COTI-2, a novel clinical stage agent, with multiple chemotherapeutic and targeted agents enhances the activity of these drugs in vitro and in vivo. Importantly, no overt toxicity was observed in the combination treatment groups in vivo. Furthermore, unlike the tested chemotherapeutic drugs, cancer cells did not develop resistance to COTI-2. Finally, some chemo-resistant tumor cell lines only showed mild cross-resistance to COTI-2 while most remained sensitive to it.

The synergic antitumor effects of paclitaxel and temozolomide co-loaded in mPEG-PLGA nanoparticles on glioblastoma cells

To get better chemotherapy efficacy, the optimal synergic effect of Paclitaxel (PTX) and Temozolomide (TMZ) on glioblastoma cells lines was investigated. A dual drug-loaded delivery system based on mPEG-PLGA nanoparticles (NPs) was developed to potentiate chemotherapy efficacy for glioblastoma. PTX/TMZ-NPs were prepared with double emulsification solvent evaporation method and exhibited a relatively uniform diameter of 206.3 ± 14.7 nm. The NPs showed sustained release character. Cytotoxicity assays showed the best synergistic effects were achieved when the weight ratios of PTX to TMZ were 1:5 and 1:100 on U87 and C6 cells, respectively. PTX/TMZ-NPs showed better inhibition effect to U87 and C6 cells than single drug NPs or free drugs mixture. PTX/TMZ-NPs (PTX: TMZ was 1:5(w/w)) significantly inhibited the tumor growth in the subcutaneous U87 mice model. These results indicate that coordinate administration of PTX and TMZ combined with NPs is an efficient method for glioblastoma.

A novel self-assembled pH-sensitive targeted nanoparticle platform based on antibody-4arm-polyethylene glycol-pterostilbene conjugates for co-delivery of anticancer drugs

Recently, antibody-drug conjugates (ADC) have shown potential for cancer immunotherapy by tumor-targeted delivery of anticancer drugs. However, the development of ADC is subject to many restrictions, such as the payloads, stabilities and intracellular uptake of the drugs, which has greatly restricted their clinical application. To overcome these hurdles, in this study, a novel pH-sensitive targeted nanoparticle platform based on a newly synthesized amphipathic antibody-drug conjugate (antibody-4arm-polyethylene glycol-pterostilbene, mAb-4arm-PEG-PS) was fabricated for co-delivery of another anticancer drug (10-hydroxy camptothecin, HCPT). The prepared mAb-4arm-PEG-PS/HCPT nanoparticles (NPs) had a moderate particle size (∼120 nm), a high drug to antibody ratio (∼22.4) and relatively high binary drug loading capacity (∼24.2 wt% HCPT, ∼2.9 wt% PS). Moreover, the mAb-4arm-PEG-PS/HCPT NPs exhibited enhanced intracellular uptake (∼5 fold that of mAb-4arm-PEG-PS conjugates) and excellent cytotoxicity in vitro. In subsequent Daudi lymphoma xenograft assays, compared with free drugs and mAb-4arm-PEG-PS conjugates, the mAb-4arm-PEG-PS/HCPT NPs inhibited tumor growth more efficiently. Our results indicated the great potential of mAb-4arm-PEG-PS/HCPT NPs for targeted co-delivery of anticancer drugs to solid tumors.

Thermo-Sensitive TRP Channels: Novel Targets for Treating Chemotherapy-Induced Peripheral Pain

Abnormal Ca²⁺ channel physiology, expression levels, and hypersensitivity to heat have been implicated in several pain states following treatment with chemotherapeutic agents. As members of the Ca²⁺ permeable transient receptor potential (TRP), five of the channels (TRPV1-4 and TRPM2) are activated by different heat temperatures, and two of the channels (TRPA1 and TRPM8) are activated by cold temperature. Accumulating evidences indicates that antagonists of TRPA1 and TRPM8 may protect against cisplatin, oxaliplatin, and paclitaxel-induced mitochondrial oxidative stress, inflammation, cold allodynia, and hyperalgesia. TRPV1 was responsible from the cisplatin-induced heat hyperalgesia and mechanical allodynia in the sensory neurons. TRPA1, TRPM8, and TRPV2 protein expression levels were mostly increased in the dorsal root (DRG) and trigeminal ganglia by these treatments. There is a debate on direct or oxaliplatin-induced oxidative cold stress dependent TRPA1 and TRPV4 activation in the DRG. Involvement of molecular pathways such as cysteine groups, glutathione metabolism, anandamide, cAMP, lipopolysaccharide, proteinase-activated receptor 2, and mitogen-activated protein kinase were also indicated in the oxaliplatin and paclitaxel-induced cold allodynia. In this review, we summarized results of five temperature-regulated TRP channels (TRPA1, TRPM8, TRPV1, TRPV2, and TRPV4) as novel targets for treating chemotherapy-induced peripheral pain

Preclinical development of drug delivery systems for paclitaxel-based cancer chemotherapy

Paclitaxel (PTX) is one of the most successful drugs ever used in cancer chemotherapy, acting against a variety of cancer types. Formulating PTX with Cremophor EL and ethanol (Taxol®) realized its clinical potential, but the formulation falls short of expectations due to side effects such as peripheral neuropathy, hypotension, and hypersensitivity. Abraxane®, the albumin bound PTX, represents a superior replacement of Taxol® that mitigates the side effects associated with Cremophor EL. While Abraxane® is now considered a gold standard in chemotherapy, its 21% response rate leaves much room for further improvement. The quest for safer and more effective cancer treatments has led to the development of a plethora of innovative PTX formulations, many of which are currently undergoing clinical trials. In this context, we review recent development of PTX drug delivery systems and analyze the design principles underpinning each delivery strategy. We chose several representative examples to highlight the opportunities and challenges of polymeric systems, lipid-based formulations, as well as prodrug strategies.

Tripalmitin nanoparticle formulations significantly enhance paclitaxel antitumor activity against breast and lung cancer cells in vitro

Paclitaxel (PTX) is one of the drugs of choice in the treatment of breast and lung cancer. However, its severe side effects, including mielosuppression, cardiotoxicity and neurotoxicity, frequently cause treatment to be discontinued. Solid lipid nanoparticles (NPs) of glyceril tripalmitate (tripalmitin) loaded with PTX (Tripalm-NPs-PTX) including modifications by the addition of hexa(ethylene glycol), β-cyclodextrin and macelignan were developed. All NPs-PTX formulations displayed excellent hemocompatibility and significantly enhanced PTX antitumor activity in human breast (MCF7, MDAMB231, SKBR3 and T47D) and lung (A549, NCI-H520 and NCI-H460) cancer cells. Tripalm-NPs-PTX decreased PTX IC₅₀ by as much as 40.5-fold in breast and 38.8-fold in lung cancer cells and Tripalm-NPs-PTX macelignan inhibited P-glycoprotein in resistant tumor cells. In addition, Tripalm-NPs-PTX significantly decreased the volume of breast and lung multicellular tumor spheroids that mimics in vivo tumor mass. Finally, Tripalm-NPs-PTX decreased the PTX IC₅₀ of cancer stem cells (CSCs) derived from both lung and breast cancer cells (6.7- and 14.9-fold for MCF7 and A549 CSCs, respectively). These results offer a new PTX nanoformulation based on the use of tripalmitin which improves the antitumor activity of PTX and that may serve as an alternative PTX delivery system in breast and lung cancer treatment.

Evidence That P-glycoprotein Inhibitor (Elacridar)-Loaded Nanocarriers Improve Epidermal Targeting of an Anticancer Drug via Absorptive Cutaneous Transporters Inhibition

Because P-glycoprotein (P-gp) plays an absorptive role in the skin, its pharmacological inhibition represents a strategy to promote cutaneous localization of anticancer agents that serve as its substrates, improving local efficacy while reducing systemic exposure. Here, we evaluated the ability of a nanoemulsion (NE) coencapsulating a P-gp inhibitor (elacridar) with the antitumor drug paclitaxel to promote epidermal targeting. Loaded NE displayed a nanometric size (45.2 ± 4.0 nm) and negative zeta potential (-4.2 ± 0.8 mV). Elacridar improved NE ability to inhibit verapamil-induced ATPase activity of P-gp; unloaded NE-inhibited P-gp when used at a concentration of 1500 μM, while elacridar encapsulation decreased this concentration by 3-fold (p <0.05). Elacridar-loaded NE reduced paclitaxel penetration into the dermis of freshly excised mice skin and its percutaneous permeation by 1.5- and 1.7-fold (p <0.05), respectively at 6 h, whereas larger drug amounts (1.4-fold, p <0.05) were obtained in viable epidermis. Assessment of cutaneous distribution of a fluorescent paclitaxel derivative confirmed the smaller delivery into the dermis at elacridar presence. In conclusion, we have provided novel evidence that NE containing elacridar exhibited a clear potential for P-gp inhibition and enabled epidermal targeting of paclitaxel, which in turn, can potentially reduce adverse effects associated with systemic exposure to anticancer therapy.

Patient-centered drug delivery and its potential applications for unmet medical needs

Pharmaceutical dosage forms address diverse key components but satisfying unmet patient needs to enhance patient adherence is a major challenge. The desired design of patient-centered drug products should be based on characteristics of various components, such as patients, disease, routes of administration, drug delivery technologies and active pharmaceutical ingredients. Understanding of targeting patients and their physiological and biological environments is pivotal for developing suitable patient-centered drug products. In this review, key components of an ideal drug delivery system were considered. Then, stepwise approaches for designing patient-centered drug products were suggested. Finally, various case studies are also presented and considered to develop models of patient-centered drug products.

Anti-MUC1 aptamer: A potential opportunity for cancer treatment

Mucin 1 (MUC1) is a protein usually found on the apical surface of most normal secretory epithelial cells. However, in most adenocarcinomas, MUC1 is overexpressed, so that it not only appears over the entire cell surface, but is also shed as MUC1 fragments into the blood stream. These phenomena pinpoint MUC1 as a potential target for the diagnosis and treatment of cancer; consequently, interest has increased in MUC1 as a molecular target for overcoming cancer therapy challenges. MUC1 currently ranks second among 75 antigen candidates for cancer vaccines, and different antibodies or aptamers against MUC1 protein are proving useful for tracing cancer cells in the emerging field of targeted delivery. The unique properties of MUC1 aptamers as novel targeting agents, and the revolutionary role that MUC1 now plays in cancer therapy, are the focus of this review. Recent advancements in MUC1-targeted cancer therapy are also assessed.

High-throughput cell mechanical phenotyping for label-free titration assays of cytoskeletal modifications

The mechanical fingerprint of cells is inherently linked to the structure of the cytoskeleton and can serve as a label‐free marker for cell homeostasis or pathologic states. How cytoskeletal composition affects the physical response of cells to external loads has been intensively studied with a spectrum of techniques, yet quantitative and statistically powerful investigations in the form of titration assays are hampered by the low throughput of most available methods. In this study, we employ real‐time deformability cytometry (RT‐DC), a novel microfluidic tool to examine the effects of biochemically modified F‐actin and microtubule stability and nuclear chromatin structure on cell deformation in a human leukemia cell line (HL60). The high throughput of our method facilitates extensive titration assays that allow for significance assessment of the observed effects and extraction of half‐maximal concentrations for most of the applied reagents. We quantitatively show that integrity of the F‐actin cortex and microtubule network dominate cell deformation on millisecond timescales probed with RT‐DC. Drug‐induced alterations in the nuclear chromatin structure were not found to consistently affect cell deformation. The sensitivity of the high‐throughput cell mechanical measurements to the cytoskeletal modifications we present in this study opens up new possibilities for label‐free dose‐response assays of cytoskeletal modifications.

Thermoresponsive nanocomposite gel for local drug delivery to suppress the growth of glioma by inducing autophagy

Although the treatments of malignant glioma include surgery, radiotherapy and chemotherapy by oral drug administration, the prognosis of patients with glioma remains very poor. We developed a polyethylene glycol-dipalmitoylphosphatidyle- thanoiamine (mPEG-DPPE) calcium phosphate nanoparticles (NPs) injectable thermoresponsive hydrogel (nanocomposite gel) that could provide a sustained and local delivery of paclitaxel (PTX) and temozolomide (TMZ). In addition, the proportion of PTX and TMZ for the optimal synergistic antiglioma effect on C6 cells was determined to be 1:100 (w/w) by the Chou and Talalay method. Our results clearly indicated that the autophagy induced by PTX:TMZ NPs plays an important role in regulating tumor cell death, while autophagy inhibition dramatically reverses the antitumor effect of PTX:TMZ NPs, suggesting that antiproliferative autophagy occurs in response to PTX:TMZ NPs treatment. The antitumor efficacy of the PTX:TMZ NP-loaded gel was evaluated in situ using C6 tumor-bearing rats, and the PTX:TMZ NP-loaded gel exhibited superior antitumor performance. The antitumor effects of the nanocomposite gel in vivo were shown to correlate with autophagic cell death in this study. The in vivo results further confirmed the advantages of such a strategy. The present study may provide evidence supporting the development of nanomedicine for potential clinical application.

Comparative study of cisplatin-based definitive concurrent chemoradiotherapy with S-1 versus paclitaxel for unresectable locally advanced esophageal squamous cell carcinoma

This study compared the efficiency and safety of definitive concurrent chemoradiotherapy (CCRT) using Paclitaxel plus Cisplatin (TP) versus S-1 plus Cisplatin (CS) in unresectable locally advanced esophageal squamous cell carcinoma (LAESCC). Between January 2009 and December 2013, 203 LAESCC patients were retrospectively reviewed. We performed a propensity score matching analysis; 41 patients treated with the CS regimen were matched 1:1 to patients who received the TP regimen. Patient- and disease-related characteristics were well-balanced between the two groups. The CS group showed significantly better treatment compliance (90.2% vs. 70.7%, P = 0.026) and less hospital stay (48 days vs 49 days, P = 0.025) over the TP group during the CCRT course. The complete response rate was comparable between the two groups (51.2% vs. 48.8%, P = 0.825). The 1- and 3-year overall survival (OS) rates in the TP group were 63.4% and 32.4% compared to 62.8% and 32.1% in the CS group, respectively (P = 0.796). The 1- and 3-year progression-free survival (PFS) rates in the TP group were 51.2% and 24.9%, compared to 53.6% and 18.9% in the CS group, respectively (P = 0.630). The incidence of severe and total neutropenia in the TP group was significantly higher compared to the CS group (P = 0.011 and 0.046, respectively). Multivariate analysis revealed that T stage and the complete response rate were strong prognostic factors associated with OS and PFS. In conclusion, both treatment regimens yielded satisfactory survival outcomes, but the CS regimen could significantly improve treatment compliance, reduce hematological toxicities and lengths of hospital stay. Future prospective studies in large cohorts are highly warranted to confirm the findings in our report.

Inhibitory effects of Leucaena leucocephala on the metastasis and invasion of human oral cancer cells

Oral cancer is one of the most common cancers worldwide, and metastasis is recognized as a major factor causing its low survival rate. The inhibition of metastasis progress and the improvement of the survival rate for oral cancer are critical research objectives. Leucaena leucocephala from the mimosa branch Leucaena genus is native to Central and South America and has been used as a traditional remedy for treating various disorders. Previous studies have demonstrated antioxidant, anti-inflammatory as well as anticancer properties of L. leucocephala plant materials. However, the molecular mechanism underlying the anticancer effect induced by L. leucocephala remains unclear. In this study, we investigated the effect of L. leucocephala extract (LLE) on SCC-9 and SAS oral cancer cells and examined the potential inhibitory mechanisms involved. The results indicated that LLE attenuated the migration and invasion abilities of both SCC-9 and SAS cells by reducing the activity and protein expression of matrix metalloproteinases-2 (MMP-2). Regarding mitogen-activated protein kinase (MAPK) pathways, the phosphorylation of ERK1/2 and p38 exhibited a significant inhibitory effect in the presence of LLE. The application of ERK inhibitor and p38 inhibitor confirmed that both signalling transduction pathways were involved in the inhibition of cell metastasis. These data indicate that L. leucocephala could be a potent therapeutic agent for the prevention and treatment of oral cancer and a prominent plant source for anticancer research in the future.

Impact of Dendrimers on Solubility of Hydrophobic Drug Molecules

Adequate aqueous solubility has been one of the desired properties while selecting drug molecules and other bio-actives for product development. Often solubility of a drug determines its pharmaceutical and therapeutic performance. Majority of newly synthesized drug molecules fail or are rejected during the early phases of drug discovery and development due to their limited solubility. Sufficient permeability, aqueous solubility and physicochemical stability of the drug are important for achieving adequate bioavailability and therapeutic outcome. A number of different approaches including co-solvency, micellar solubilization, micronization, pH adjustment, chemical modification, and solid dispersion have been explored toward improving the solubility of various poorly aqueous-soluble drugs. Dendrimers, a new class of polymers, possess great potential for drug solubility improvement, by virtue of their unique properties. These hyper-branched, mono-dispersed molecules have the distinct ability to bind the drug molecules on periphery as well as to encapsulate these molecules within the dendritic structure. There are numerous reported studies which have successfully used dendrimers to enhance the solubilization of poorly soluble drugs. These promising outcomes have encouraged the researchers to design, synthesize, and evaluate various dendritic polymers for their use in drug delivery and product development. This review will discuss the aspects and role of dendrimers in the solubility enhancement of poorly soluble drugs. The review will also highlight the important and relevant properties of dendrimers which contribute toward drug solubilization. Finally, hydrophobic drugs which have been explored for dendrimer assisted solubilization, and the current marketing status of dendrimers will be discussed.

Cell line studies and analytical measurements of three paclitaxel complex variations

The copper(II) cation, sucrose, and hydroxychloroquine were complexed with the chemotherapy agent paclitaxel and studied for medicinal activity. Data (GI₅₀, LD₅₀) from single dose and five dose National Cancer Institute sixty cell line panels are presented. Analytical measurements of different complexes were made using Nuclear Magnetic Resonance (¹H NMR), Matrix Assisted Laser Desorption Ionization-Time of Flight-Mass Spectrometry (MALDI-TOF-MS) and Fourier Transform-Ion Cyclotron Resonance (FT-ICR). Molecular modeling is utilized to better understand the impact that species could have on physical parameters associated with Lipinski's Rule of Five, such as logP and TPSA. On average, Cu(II) and hydroxychloroquine decreased GI₅₀ values, while sucrose increased GI₅₀ values of paclitaxel.

F10, a novel hydatidiform mole-associated gene, inhibits the paclitaxel sensitivity of A549 lung cancer cells by downregulating BAX and caspase-3

F10 is a novel hydatidiform mole (HM)-associated gene that was initially identified during a study into the pathogenesis of HMs. However, the role of the F10 gene requires further investigation. Our, previous studies have indicated that F10 may be involved in the malignant transformation of HMs and the development of certain types of adenocarcinoma, and that the overexpression of F10 may lead to excessive proliferation and decreased apoptosis of A549 cells. The present study aimed to investigate whether F10 may suppress the sensitivity of A549 lung cancer cells to paclitaxel therapy. A previously established F10-overexpressing A549 cell line (A549-F10) was treated with paclitaxel, using untransfected A549 cells and A549-mock cells (non-carrier A549) as the controls. These three groups of cells were subsequently examined by an MTT cell proliferation assay and a TUNEL-fluorescein isothiocyanate/Hoechst 33258 apoptosis assay. A western blot analysis was used to determine the expression levels of the pro-apoptotic genes B-cell lymphoma-2-associated X protein (BAX) and caspase-3. The effects of paclitaxel treatment on the proliferation and apoptosis of A549 cells were compared between the aforementioned cell lines. It was revealed that F10 inhibited the chemosensitivity of A549 cells to paclitaxel, as demonstrated by the decreased rates of growth inhibition and apoptosis in the A549-F10 group compared with the two control groups. Furthermore, the A549-F10 cells treated with paclitaxel exhibited significantly lower expression levels of the pro-apoptotic genes. The results of the current study demonstrate that F10 may inhibit the chemosensitivity of A549 cells to paclitaxel and that this inhibitory effect may be mediated by the downregulation of BAX and caspase-3 expression, which subsequently inhibits cell apoptosis.