Docetaxel-associated epiphora

Dacryoendoscopic Findings of Patients with Lacrimal Drainage Obstruction Associated with Cancer Treatment

PURPOSE

To compare the diagnosis and treatment outcome of lacrimal drainage obstruction of patients who underwent systemic chemotherapy (CTx) or radioactive iodine treatment (RAI) by using dacryoendoscopy and at the same time performing dacryoendoscopy-guided silicone tube insertion (STI) to treat epiphora.

METHODS

From July 2017 to December 2020, the medical records of 11 patients (16 eyes) were diagnosed with lacrimal drainage obstruction after CTx or RAI and underwent dacryoendoscopy-guided STI were reviewed retrospectively. We tried to count the number of obstructive sites in total patients using slit-lamp examination and dacryoendoscopic findings.

RESULTS

A total of 11 patients, 16 eyes, were enrolled in this study. The onset of epiphora in the CTx group (3.0 ± 4.0 months) was significantly shorter than that in the RAI group (52.6 ± 36.5 months, p = 0.001). There were total 32 obstructive sites including 28 obstructive sites of dacryoendoscopic findings and four sites of punctual stenosis in total 16 cases. Using dacryoendoscopy, granulation findings was dominant in RAI patients (p = 0.038) and mucus finding was frequent mostly in lacrimal sac and canaliculus. In the CTx group, mucosal edema finding was dominant (p = 0.038) and fibrotic membrane finding was frequent in all levels of lacrimal drainage system. Regarding the obstructive location, lacrimal sac was the most frequently obstructed site in the two groups (p = 0.038).

CONCLUSIONS

The onset of epiphora in the CTx group was significantly earlier than in the RAI group. In the CTx group, mucosal edema finding was frequent in all levels of lacrimal drainage system. In the RAI group, granulation finding was frequent mostly in lacrimal sac and canaliculus. Since the clinical outcome was satisfactory, intervention with dacryoendoscopy-guided STI could be a treatment of choice in patients with epiphora after CTx or RAI.

Docetaxel for Breast Cancer Treatment-Side Effects on Ocular Surface, a Systematic Review

Docetaxel is a very effective chemotherapeutic agent for the treatment of metastatic or locally advanced breast cancer. Epiphora (hyperlacrimation) has been shown to be the most common eye condition in patients receiving docetaxel-based chemotherapy. This symptom does not decrease visual acuity, but decreases the quality of life. Daily activities (reading, working on the computer, watching TV, and so on) are affected, with patients complaining about an alteration of daily life with the appearance of this symptom. The mechanism by which epiphora occurs is considered to be the canalicular stenosis, but the trials on the subject failed to reach statistical significance. The objective of this scoping review is to determine whether there is a treatment regimen-dependent relationship between docetaxel administration and the presence of epiphora in women with breast cancer. The inclusion criteria were met by 10 trials, from which one was excluded owing to data selection biases. Accordingly, nine studies were evaluated quantitatively and qualitatively in the present review. We included subjects with docetaxel as single treatment or docetaxel in combination with other chemotherapy compounds. The occurrence of epiphora among subjects treated with docetaxel, regardless of the therapeutic regimen used, was statistically significant (p = 0.005). The proportion of patients with epiphora after weekly administration of docetaxel (54 out of 131 subjects, 41.22%) was different compared with that of those who received docetaxel at three week intervals (112 out of 325 subjects, 34.15%), but the difference between the two was not statistically significant (p = 0.732). The present study demonstrates that epiphora occurs more frequently in patients receiving weekly docetaxel-based chemotherapy than those taking the three-weekly regimen, but the difference is not statistically significant. Ophthalmologic assessment of all patients starting this treatment is recommended. The causal relationship between canalicular stenosis and epiphora is not fully elucidated as long as this ocular symptom occurs in women who do not have stenosis of the lacrimal system. Further well-designed trials are required to bring new insights into the mechanisms of epiphora pathogenesis in subjects treated with docetaxel.

Achievements in Thermosensitive Gelling Systems for Rectal Administration

Rectal drug delivery is an effective alternative to oral and parenteral treatments. This route allows for both local and systemic drug therapy. Traditional rectal dosage formulations have historically been used for localised treatments, including laxatives, hemorrhoid therapy and antipyretics. However, this form of drug dosage often feels alien and uncomfortable to a patient, encouraging refusal. The limitations of conventional solid suppositories can be overcome by creating a thermosensitive liquid suppository. Unfortunately, there are currently only a few studies describing their use in therapy. However, recent trends indicate an increase in the development of this modern therapeutic system. This review introduces a novel rectal drug delivery system with the goal of summarising recent developments in thermosensitive liquid suppositories for analgesic, anticancer, antiemetic, antihypertensive, psychiatric, antiallergic, anaesthetic, antimalarial drugs and insulin. The report also presents the impact of various types of components and their concentration on the properties of this rectal dosage form. Further research into such formulations is certainly needed in order to meet the high demand for modern, efficient rectal gelling systems. Continued research and development in this field would undoubtedly further reveal the hidden potential of rectal drug delivery systems.

Docetaxel-Loaded Chitosan-Cholesterol Conjugate-Based Self-Assembled Nanoparticles for Overcoming Multidrug Resistance in Cancer Cells

Cholesteryl hemisuccinate (CHS)-conjugated chitosan (CS)-based self-assembled nanoparticles (NPs) were developed for enhancing the intracellular uptake of docetaxel in multidrug resistance (MDR)-acquired cancer cells. CHS-CS was successfully synthesized and self-aggregation, particle size, zeta potential, drug entrapment efficiency, and in vitro drug release of docetaxel-loaded CHS-CS NPs were tested. The optimized NPs had a mean hydrodynamic diameter of 303 nm, positive zeta potential of 21.3 mV, and spherical shape. The in vitro release of docetaxel from the optimized CHS-CS NPs in different pH medium (pH 6.0 and 7.4) revealed that the release was improved in a more acidic condition (pH 6.0), representing a tumor cell's environment. The superior MDR-overcoming effect of docetaxel-loaded CHS-CS NPs, compared with docetaxel solution, was verified in anti-proliferation and cellular accumulation studies in MDR-acquired KBV20C cells. Thus, CHS-CS NPs could be potentially used for overcoming the MDR effect in anticancer drug delivery.

Multifunctional Biomedical Adhesives

Currently available biomedical adhesives are mainly engineered to have one function (i.e., providing mechanical support for the repaired tissue). To improve the performance of existing bioadhesives and broaden their applications in medicine, numerous multifunctional bioadhesives are reported in the literature. These adhesives can be categorized as passive or active by design. Passive multifunctional bioadhesives contain inherent compositions and structural designs that can carry out additional functions without added external influences. These adhesives exhibit new functionalities such as antimicrobial properties, self-healing abilities, the ability to promote cellular ingrowth, and the ability to be reshaped. Conversely, active multifunctional bioadhesives respond to environmental changes (e.g., pH, temperature, electricity, light, and biomolecule concentration), which initiate a change in the adhesive to release encapsulated drugs or to activate or deactivate the bioadhesive for interfacial binding. This review article highlights recent advances in multifunctional bioadhesives.

ACCELERATED ONSET OF RETINAL TOXICITY FROM HYDROXYCHLOROQUINE USE WITH CONCOMITANT BREAST CANCER THERAPY

PURPOSE

To report a case of accelerated retinal toxicity due to hydroxychloroquine (HCQ) use for treatment of Sjögren syndrome in a patient treated with concomitant chemotherapy for breast cancer.

METHODS

Observational case report.

RESULTS

A 56-year-old white woman using 400 mg HCQ (7.1 mg/kg real body weight) daily for a total of 2 years and 10 months for treatment of Sjögren syndrome with concomitant use of docetaxel and cyclophosphamide therapy (21-day cycle, 4 cycles) followed by anastrozole for breast cancer, presented with visual complaints and findings of severe HCQ toxicity.

CONCLUSION

Concomitant breast cancer therapy may have a synergistic effect with HCQ leading to accelerated retinal toxicity. As such potential acceleration is poorly understood, patients on HCQ who are treated with concomitant chemotherapy should be considered for more frequent retinal screenings to maximize safety and preservation of vision.

Folate-Functionalized Thiomeric Nanoparticles for Enhanced Docetaxel Cytotoxicity and Improved Oral Bioavailability

To achieve remotely directed delivery of anticancer drugs, surface-decorated nanoparticles with ligands are reported. In this study, folic acid- and thiol-decorated chitosan nanoparticles loaded with docetaxel (DTX-NPs) were prepared for enhanced cellular internalization in cancer cells and improved oral absorption. The DTX-NPs were explored through in vitro and in vivo parameters for various parameters. The DTX-NPs were found to be monodisperse nanoparticles with an average particle size of 158.50 ± 0.36 nm, a polydispersity index of 0.36 ± 0.0, a zeta potential of + 18.30 ± 2.52 mV, and an encapsulation efficiency of 71.47 ± 5.62%. The drug release from DTX-NPs followed the Korsmeyer-Peppas model with about 78% of drug release in 12 h. In in vitro cytotoxicity studies against folate receptor, positive MDA-MBB-231 cancerous cells showed improved cytotoxicity with IC₅₀ of 0.58 μg/mL, which is significantly lower as compared to docetaxel (DTX). Ex vivo permeation enhancement showed an efflux ratio of 0.99 indicating successful transport across the intestine. Oral bioavailability was significantly improved as C_max and AUC were higher than DTX suspension. Overall, the results suggest that DTX-NPs can be explored as a promising carrier for oral drug delivery.

Significant Suppression of Non-small-cell Lung Cancer by Hydrophobic Poly(ester amide) Nanoparticles with High Docetaxel Loading

Non-small-cell lung cancer (NSCLC) accounts for over 85% of clinical lung cancer cases, which is the leading cause of cancer-related death. To develop new therapeutic strategy for NSCLC, a library of L-phenylalanine-based poly(ester amide) (Phe-PEA) polymers was synthesized and assembled with docetaxel (Dtxl) to form Dtxl-loaded Phe-PEA nanoparticles (NPs). The hydrophobic Phe-PEA polymers were able to form NPs by nanoprecipitation method and the characterization results showed that the screened Dtxl-8P4 NPs have small particle size (∼100 nm) and high Dtxl loading (∼20 wt%). In vitro experiments showed that Dtxl-8P4 NPs were rapidly trafficked into cancer cells, then effectively escaped from lysosomal degradation and achieved significant tumor cell inhibition. In vivo results demonstrated that Dtxl-8P4 NPs with prolonged blood circulation could efficiently deliver Dtxl to A549 tumor sites, leading to reduced cell proliferation, block metastasis, and increase apoptosis, then persistent inhibition of tumor growth. Therefore, Phe-PEA NPs are able to load high amount of hydrophobic drugs and could be a promising therapeutic approach for NSCLC and other cancer treatments.

Cancer-associated epiphora: a retrospective analysis of referrals to a tertiary oculoplastic practice

AIM

To report the underlying causes and treatment outcome of lacrimal drainage obstruction in patients with cancer-associated epiphora.

METHODS

A single-centre retrospective review was performed for consecutive referrals to an oculoplastic surgeon for cancer-associated epiphora between 2010 and 2016. Charts were reviewed for underlying neoplastic conditions, pharmacy records, radiotherapy records, levels of obstruction of the lacrimal drainage apparatus and treatment methods and outcome.

RESULTS

Forty-three patients (70 eyes) were included in this study. The most common cause of epiphora was radiotherapy on the head and neck (35%), followed by oral S-1 (33%) and docetaxel (23%). The nasolacrimal duct was the most common obstruction site in patients who underwent radiotherapy (59%), whereas the punctum or canaliculus was mostly affected in patients treated with S-1 (94%) or docetaxel (100%). S-1-treated patients showed severe obstruction of the entire canaliculus (11/24 (46%)) with the lowest success rate at 58% (S-1 vs radiotherapy: p=0.012; S-1 vs docetaxel: p=0.002). Moreover, the patients treated within 1 year after the first symptom showed a significantly higher proportion of symptom improvement (85%) than did those treated after 1 year (27%) in the S-1 group (p=0.011).

CONCLUSIONS

Cancer-associated epiphora can have various causes. The level of obstruction and treatment outcome vary according to underlying causes, and S-1-associated epiphora and delayed treatment are related to unsatisfactory results. Given the importance of early intervention, oncologists should be alert to tearing symptoms and cooperate with ophthalmologists in the early stages to improve patients' quality of life.

Polymeric mixed micelles as nanomedicines: Achievements and perspectives

During the past few decades, polymeric micelles have raised special attention as novel nano-sized drug delivery systems for optimizing the treatment and diagnosis of numerous diseases. These nanocarriers exhibit several in vitro and in vivo advantages as well as increased stability and solubility to hydrophobic drugs. An interesting approach for optimizing these properties and overcoming some of their disadvantages is the combination of two or more polymers in order to assemble polymeric mixed micelles. This review article gives an overview on the current state of the art of several mixed micellar formulations as nanocarriers for drugs and imaging probes, evaluating their ongoing status (preclinical or clinical stage), with special emphasis on type of copolymers, physicochemical properties, in vivo progress achieved so far and toxicity profiles. Besides, the present article presents relevant research outcomes about polymeric mixed micelles as better drug delivery systems, when compared to polymeric pristine micelles. The reported data clearly illustrates the promise of these nanovehicles reaching clinical stages in the near future.

The role of docetaxel in the treatment of non-small cell lung cancer lung cancer: an update

INTRODUCTION

Non-small cell lung cancer lung cancer (NSCLC) is a devastating disease, with poor prognosis for patients with metastatic disease. The management of these patients has evolved during the past decade, challenging the role of cytotoxic chemotherapy as the only available treatment option. Nevertheless, chemotherapy still retains a dominant position for the majority of both treatment naïve and pretreated patients. Among the chemotherapeutic agents, docetaxel is one of the most commonly used in 1st and subsequent treatment lines, even in the current era of precision medicine. Areas covered: We searched Medline, Embase, Scopus and Cochrane Library for randomized phase III trials that evaluated docetaxel in various clinical settings of NSCLC and for meta-analyses of such trials and we present all relevant data regarding the pharmacology and clinical use of docetaxel in NSCLC. Expert commentary: Despite its diminishing role, docetaxel in combination with novel targeted agents remains an important option of the therapeutic armamentarium in advanced NSCLC.

Docetaxel Facilitates Endothelial Dysfunction through Oxidative Stress via Modulation of Protein Kinase C Beta: The Protective Effects of Sotrastaurin

Docetaxel (DTX), a taxane drug, has widely been used as an anticancer or antiangiogenesis drug. However, DTX caused side effects, such as vessel damage and phlebitis, which may reduce its clinical therapeutic efficacy. The molecular mechanisms of DTX that cause endothelial dysfunction remain unclear. The aim of this study as to validate the probable mechanisms of DTX-induced endothelial dysfunction in endothelial cells. Human umbilical vein endothelial cells (HUVECs) were stimulated with DTX (2.5, 5, and 10nM) for 24 h to induce endothelial dysfunction. Stimulation with DTX reduced cell viability in a concentration- and time-dependent manner. DTX upregulated caspase-3 activity and TUNEL-positive cells. DTX treatment also increased PKCβ phosphorylation levels and NADPH oxidase activity, which resulted in ROS formation. However, all of these findings were reversed by PKCβ inhibition and NADPH oxidase repression. Finally, we demonstrated that sotrastaurin (AEB-071), a new PKCβ inhibitor, mitigated DTX-induced oxidative injury in endothelial cells. Our findings from this study provide a probable molecular mechanism of DTX-induced oxidative injury in endothelial cells and a new clinical and therapeutic approach for preventing DTX-mediated vessel injury.

Pharmacokinetics and toxicology of a fibroblast activation protein (FAP)-activated prodrug in murine xenograft models of human cancer

BACKGROUND

As carcinoma progresses, the stroma undergoes a variety of phenotypic changes, including the presence of carcinoma-associated fibroblasts (CAFs) that express fibroblast activation protein (FAP). FAP is a post-prolyl endopeptidase whose expression in a healthy adult is largely restricted to the cancer-associated stroma. FAP-targeted prodrugs with a 100-fold greater therapeutic window over the parent compound were previously generated.

METHODS

Prodrugs and non-cleavable controls were incubated in the presence of FAP. Plasma and tumor half-lives (t1/2) of the full-length and active forms of the prodrugs were determined using LCMS. Biodistribution studies of prodrug activation were performed. Histopathological analysis of tissues from treated animals were compared to vehicle-treated controls. Toxicity and efficacy studies were performed in human breast (MDA-MB-231 and MCF-7) and prostate (LNCaP) cancer xenografts models.

RESULTS

These FAP-activated prodrugs have a significantly slower clearance from tumor tissue than the circulation (∼12 vs. ∼4.5 hr). Micromolar concentrations of active drug persist in the tumor. Active drug is detected in non-target tissues; however, histopathologic evaluation reveals no evidence of drug-induced toxicity. A FAP-activated prodrug (ERGETGP-S12ADT) inhibits tumor growth in multiple human breast and prostate cancer xenograft models. The anti-tumor effect is comparable to that observed with docetaxel, but results in significantly less toxicity.

CONCLUSION

FAP-activated prodrugs are a viable strategy for the management of prostate and other cancers. These prodrugs exhibit less toxicity than a commonly used chemotherapeutic agent. Further refinement of the FAP cleavage site for greater specificity may reduce prodrug activation in non-target tissues and enhance clinical benefit.

The influence of bile salt on the chemotherapeutic response of docetaxel-loaded thermosensitive nanomicelles

The primary aim of this work was to investigate the potential of bile salt, sodium taurocholate (NaTC), in improving the bioavailability and anti-tumor efficacy of docetaxel (DCT) upon rectal administration. Poloxamer-based nanomicelles with thermosensitive and mucoadhesive properties were prepared using the cold method. The optimized nanomicellar formulation was evaluated in terms of physicochemical and viscoelastic parameters. Nanomicelles containing bile salt maintained sufficient gelation strength (234×10² mPa·s) and mucoadhesive force (17.3×10² dyne/cm²) to be retained in the upper part of the rectum. They significantly enhanced the DCT internalization across the rectal mucosa and showed a high plasma level during the first 4 hours of the study period, compared to nanomicelles with no bile salt. As a result, a slightly higher rectal bioavailability of ~33% was observed in nanomicelles containing bile salt, compared to ~28% from the latter system. The higher pharmacokinetic parameters for rectally administered DCT/P407/P188/Tween 80/NaTC (0.25%/11%/15%/10%/0.1% by weight, respectively) resulted in significant anti-tumor efficacy. However, the tumor regression rate for the NaTC group was not statistically different from that for nanomicelles without NaTC. Therefore, overall results suggest that thermosensitive nanomicelles could be a potential dosage form for improvement of the bioavailability and chemotherapeutic profile of DCT.

Epiphora in lung cancer patients receiving docetaxel: a case series

Background

Docetaxel is a key antineoplastic drug for treatment of non-small cell lung cancer. Ocular adverse events of docetaxel include epiphora (excess tearing) and conjunctivitis. Epiphora has been reported to be associated with canalicular and nasolacrimal duct stenosis, but it is not necessarily caused by lacrimal duct obstruction.

Case presentation

We encountered three Japanese non-small cell lung cancer patients who developed epiphora after the administration of docetaxel-based chemotherapy. One patient with lacrimal puncta stenosis showed improvement with probing and irrigation. The other two patients resolved following cessation of docetaxel or administration of artificial tears.

Conclusion

As epiphora can interfere with activities of daily life and negatively affect quality of life, it is important for thoracic oncologists to be aware of this adverse event.

Toxic optic neuropathy in the setting of docetaxel chemotherapy: a case report

BACKGROUND

To describe the first reported case of toxic optic neuropathy secondary to docetaxel (Taxotere®) chemotherapy.

CASE PRESENTATION

A 53-year-old female presented with predominantly unilateral visual loss, but extensive bilateral visual field defects and bilateral optic nerve head swelling 2 weeks after first dose of docetaxel (Taxotere®) and trastuzumab (Herceptin®) chemotherapy for a left sided node-positive, HER2 positive breast cancer. Extensive investigation ruled out other causes of optic neuropathy. She was treated with high dose corticosteroids intravenously for 1 week then a tapering oral dose over 8 weeks. Visual field defects gradually resolved and visual acuity improved. Docetaxel chemotherapy was discontinued but targeted therapy with trastuzumab continued without further complication.

CONCLUSION

Docetaxel can cause a toxic optic neuropathy possibly due to an ischemic or neurotoxic mechanism at the optic nerve head. With cessation of docetaxel therapy and treatment with systemic corticosteroids, visual recovery can occur without significant residual visual deficit.

Docetaxel-loaded thermosensitive liquid suppository: optimization of rheological properties

The main purpose of this work was to optimize the rheological properties of docetaxel (DCT)-loaded thermosensitive liquid suppositories for rectal administration. DCT-loaded liquid suppositories were prepared by a cold method and characterized in terms of physicochemical and viscoelastic properties. Major formulation parameters including poloxamer (P407) and Tween 80 were optimized to adjust the thermogelling and mucoadhesive properties for rectal administration. Notably, the gel strength and mucoadhesive force significantly increased with the increase in these variables. Furthermore, DCT incorporation did not alter the viscoelastic behavior, and the mean particle size of nanomicelles in it was approximately 16 nm with a distinct spherical shape. The formulation existed as liquid at room temperature and transformed into gel at physiological temperature through the reverse gelation phenomenon. Thus, DCT-loaded thermosensitive liquid suppositories [DCT/P407/P188/Tween 80 (0.25/11/15/10 %)] with optimal gel properties were easy to prepare and administer rectally, and might enable the gel to stay in the rectum without getting out from rectum.

Prevalence of Excessive Tearing in Women With Early Breast Cancer Receiving Adjuvant Docetaxel-Based Chemotherapy

Purpose

To define the incidence and impact of tearing in patients receiving adjuvant docetaxel-based chemotherapy and assess for lacrimal duct obstruction (LDO) as a causative factor.

Patients and Methods

Consecutive patients with early breast cancer recommended for docetaxel-based chemotherapy with no prior ocular symptoms were included. Before and after completion of chemotherapy, patients underwent lacrimal drainage evaluation by computed tomographic dacrocystography (CT-DCG) and ophthalmic assessment. Eye symptoms were assessed at baseline, during, and after completion of chemotherapy.

Results

Over a 22-month period, 100 patients were recruited. Asymptomatic LDO was present at baseline in 17% and 18% of patients, as assessed by ophthalmic review and CT-DCG, respectively. Overall, 86% of patients developed tearing, with no significant difference between those who did and did not have LDO (94% v 84%; P = .45). Blepharitis occurred in 37% and minor corneal epitheliopathy in 22% of patients, with neither condition predicting for the development of tearing. Impairment of visual activities was greatest after cycle one (70% of patients) but had decreased to < 5% by 4 months after treatment.

Conclusion

Tearing occurs in the majority of patients receiving adjuvant docetaxel-based chemotherapy regimens and occurred similarly in patients with and without LDO. There was poor concordance between CT-DCG and ophthalmic examination in the detection of LDO. Tearing and other eye symptoms impaired visual activities, but in nearly all patients, both symptoms and functional impairment were mild and had resolved by 4 months after chemotherapy. Our study demonstrates docetaxel-related tearing is not caused by LDO, and as such, evaluation or stenting of the duct is not considered necessary.

Docetaxel-loaded thermosensitive and bioadhesive nanomicelles as a rectal drug delivery system for enhanced chemotherapeutic effect

PURPOSE

To investigate the potential of thermosensitive and biadhesive nanomicelles in improving the bioavailability of docetaxel (DCT) and its chemotherapeutic effect.

METHOD

DCT-loaded nanomicelles were prepared by emulsufication and characterized in terms of physico-chemical and visco-elastic parameters. The optimzed formulation was evaluated for in vivo localization, pharmacokinetic and anti-tumor efficacy.

RESULTS

The hydrodynamic size of DCT-loaded nanomicelles was approximately 13 nm and the nanomicelles exhibited a sufficient gelation strength (9250 mPa·s) and bioadhesive force (2100 dyn/cm²) to be retained in the upper part of rectum. We observed a high rectal bioavailability of 29% DCT compared to that following oral administration in rats, as it successfully evaded the multidrug efflux transporters and hepatic first-pass metabolism. Plasma concentration around ∼50 ng/mL was maintained throughout the study period (12 h) while Taxotere® attained subtherapeutic range within 4 h of drug administration. Results also revealed that the rectally administered DCT-loaded nanomicelles exhibited a significant anti-tumor effect (200 mm³) with a reduced toxicity profile when compared to orally administered DCT (950 mm³). Furthermore, histological study showed that the rectal mucosa was completely intact with no signs of irritation upon treatment with DCT-loaded nanomicelles.

CONCLUSIONS

Taken together, our novel thermosensitive and biadhesive nanomicelles demonstrated the ability to improve the bioavailability and chemotherapeutic potential of DCT in vivo. To the best of our knowledge, this is the first report describing the rectal delivery of DCT-loaded nanomicelles.

A novel monomethoxy polyethylene glycol-polylactic acid polymeric micelles with higher loading capacity for docetaxel and well-reconstitution characteristics and its anti-metastasis study

Docetaxel (DTX) is hydrophobic, and its available formulations (Taxotere(®) & Duopafei(®)) require Tween80 and ethanol vehicle to allow parental administration. DTX-loaded poly(D,L-lactide)-b-polyethylene glycol-methoxy (mPEG-b-PDLLA) polymeric micelle (PM) is a Tween80-free formulation of DTX, which has been extensively studied but rarely involved with industrialization issues. In this work, novel DTX-PM with improved loading capacity and well-reconsitution ability was developed. The freeze-dried DTX-PM was analyzed by HPLC, transmission electron microscopy (TEM) and dynamic light scattering (DLS) to determine the DTX loading, micelle morphology and size respectively. The in vitro cytotoxic activity of DTX-PM in 4T1 cells was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and the corresponding in vivo study was assessed in BALB/c mice bearing 4T1 tumor through intravenous administration. The DTX-loading and efficiency into the micelles were 20.74±1.23% and 93.7±1.03% respectively, which was much higher than ever reported PM. The DTX-PM was spherical with a mean particle size of 16.62±0.31 nm, which suggested that they were able to selectively accumulate in solid tumors by enhanced permeability and retention (EPR) effect. Another important characteristic of DTX-PM is the long term storage and reuses as aqueous injection solution. Many kinds of lyoprotectants were also investigated and dextrose was found to an excellent one. Compared with Duopafei(®), DTX-PM showed better cytotoxicity and anti-metastasis ability against 4T1 cells in vitro and in vivo. In conclusion, DTX-PM significantly enhanced drug-loading capacity of DTX and had well-reconsitution ability, which could be a promising drug delivery system for clinic.

Epiphora after radioactive iodine ablation for thyroid cancer

BACKGROUND

Epiphora is a condition in which an overflow of tears occurs because of excessive lacrimal secretion or insufficient drainage of tears due to obstruction of the nasolacrimal system. This ophthalmic complication can be an intermediate to late sequela of radioactive iodine ((131)I) therapy in thyroid cancer patients.

PATIENT FINDINGS

We present a case of a 23-year-old woman with complaints of bilateral excessive tearing 6 months after (131)I therapy for well-differentiated thyroid cancer. She was diagnosed with epiphora secondary to nasolacrimal duct obstruction (NDO) and had bilateral endoscopic dacryocystorhinostomy, which resulted in complete resolution of her symptoms.

SUMMARY

The sodium iodide symporter, present in cells of the lacrimal drainage system, is the potential mechanism by which (131)I therapy can cause inflammation, fibrosis, and ultimate obstruction of tear outflow. Risk factors such as (131)I dose, female sex, older age, and anatomical variations may also play a role in the obstruction. However, the precise pathophysiologic mechanisms remain incompletely understood.

CONCLUSIONS

NDO is an under-recognized complication of (131)I therapy in thyroid cancer patients. Questions regarding eye symptoms should be an integral part of clinical follow-up in management of such patients so that effective intervention may be performed.

Self-assembled methoxy poly(ethylene glycol)-cholesterol micelles for hydrophobic drug delivery

To promote the application of methoxy poly(ethylene glycol)-cholesterol (mPEG-Chol), mPEG-Chol was used to prepare core-shell micelles encapsulating poorly water-soluble docetaxel (DTX-PM) by modified cosolvent evaporation method. Approaches to enhance DTX entrapment efficiency (EE) and minimize particle size were investigated in detail, including organic and aqueous phase composition, organic/aqueous phase ratio, and polymer concentration. In optimal formulation, micelles had higher EE (97.6%) and drug loading (4.76%) with the diameter of 13.76 ± 0.68 nm and polydispersity index of 0.213 ± 0.006. Transmission electron microscopy (TEM) showed that the micelles were spherical, and differential scanning calorimetry (DSC) analysis proved that DTX was successfully entrapped into mPEG-Chol micelles. The in vitro cytotoxicity experiments displayed that blank micelles had no effect on the growth of SKOV-3, BXPC-3, A549, and HepG-2 cells, demonstrating that mPEG-Chol was one of the biocompatible biomaterials. The half inhibition concentration of DTX-PM on SKOV-3, BXPC-3, A549, and HepG-2 cells were 10.08, 7.6, 28.37, and 125.75 ng/mL, respectively. DTX-PM had the similar antitumor activity to free DTX, indicating that mPEG-Chol was a promising micellar vector for hydrophobic drug delivery. In addition, this work provided a new and facile approach to prepare drug-loaded micelles with controllable performances.

Lacrimal drainage obstruction in gastric cancer patients receiving S-1 chemotherapy

BACKGROUND

This study was conducted to determine the incidence and clinical characteristics of lacrimal drainage obstruction (LDO) in patients receiving S-1 chemotherapy.

PATIENTS AND METHODS

Consecutive 170 patients with gastric cancer who underwent curative surgery and received adjuvant S-1 chemotherapy were enrolled. S-1 was administered orally (40 mg/m2 b.i.d. on days 1-28 every 6 weeks) for 1 year. Ophthalmologic examinations were carried out on patients complaining of epiphora.

RESULTS

Thirty-one patients (18%) developed epiphora. Among 31 patients, 25 underwent ophthalmologic examinations and 22 (88%) were diagnosed with LDO. The median time to the onset of LDO was 2.9 months. The most common site of obstruction was the nasolacrimal duct [86% (19/22)]; punctal [23% (5/22)] and canalicular obstruction [14% (3/22)] were also noted. In multivariate analysis, total gastrectomy [versus partial gastrectomy: hazard ratio (HR), 2.9; P=0.014] and creatinine clearance<50 ml/min (versus ≥50 ml/min: HR, 2.9; P=0.038) were independent risk factors for the development of LDO.

CONCLUSION

Considering the high incidence of LDO in patients receiving S-1 chemotherapy, oncologists should be alert to epiphora and cooperate with ophthalmologists in the early stages to improve the quality of life of patients and avoid more complicated ophthalmologic procedures.

Docetaxel-loaded composite nanoparticles formed by a temperature-induced phase transition for cancer therapy

Docetaxel-loaded composite nanoparticles were prepared by temperature-induced phase transition of a mixture composed of Pluronic F-68 and liquid Tween 80/soybean oil containing docetaxel. Liquid soybean oil/Tween 80 was used as a solubilizer for docetaxel and Pluronic F-68 to stabilize the liquid soybean oil/Tween 80 containing docetaxel. The phase transition was performed at low temperature to avoid degradation. The docetaxel composite nanoparticles were injected into the tail veins of tumor-bearing mice to evaluate the composite delivery system for the release pattern and the tumor growth. The tumor-targeting capability of composite nanoparticles was verified by noninvasive live animal imaging for the time-dependent excretion profile, the in vivo biodistribution, and the circulation time.

Breast cancer medications and vision: effects of treatments for early-stage disease

This review concerns the effects on vision and the eye of medications prescribed at three phases of treatment for women with early-stage breast cancer (BC): (1) adjuvant cytotoxic chemotherapy, (2) adjuvant endocrine therapy, and (3) symptomatic relief. The most common side effects of cytotoxic chemotherapy are epiphora and ocular surface irritation, which can be caused by any of several different regimens. Most notably, the taxane docetaxel can lead to epiphora by inducing canalicular stenosis. The selective-estrogen-receptor-modulator (SERM) tamoxifen, long the gold-standard adjuvant-endocrine-therapy for women with hormone-receptor-positive BC, increases the risk of posterior subcapsular cataract. Tamoxifen also affects the optic nerve head more often than previously thought, apparently by causing subclinical swelling within the first 2 years of use for women older than ∼50 years. Tamoxifen retinopathy is rare, but it can cause foveal cystoid spaces that are revealed with spectral-domain optical coherence tomography (OCT) and that may increase the risk for macular holes. Tamoxifen often alters the perceived color of flashed lights detected via short-wavelength-sensitive (SWS) cone response isolated psychophysically; these altered perceptions may reflect a neural-response sluggishness that becomes evident at ∼2 years of use. The aromatase inhibitor (AI) anastrozole affects perception similarly, but in an age-dependent manner suggesting that the change of estrogen activity towards lower levels is more important than the low estrogen activity itself. Based on analysis of OCT retinal thickness data, it is likely that anastrozole increases the tractional force between the vitreous and retina. Consequently, AI users, myopic AI users particularly, might be at increased risk for traction-related vision loss. Because bisphosphonates are sometimes prescribed to redress AI-induced bone loss, clinicians should be aware of their potential to cause scleritis and uveitis occasionally. We conclude by suggesting some avenues for future research into the visual and ocular effects of AIs, particularly as relates to assessment of cognitive function.

Docetaxel in the treatment of non-small cell lung carcinoma: an update and analysis

Docetaxel, a semisynthetic taxane, was the first agent to show efficacy in the second-line treatment of non-small cell lung cancer (NSCLC), and has since become a mainstay of NSCLC therapy. We review its mode of action, pharmacology, toxicity and efficacy and describe both its established role in the treatment of NSCLC and future directions in research. Docetaxel works primarily by promoting microtubule assembly and polymerization, and through this hyperstabilization, causes cell cycle arrest and death. The primary toxicity of docetaxel is neutropenia, which can be mitigated by weekly administration in selected patients. Less common toxicities are peripheral edema, which can be reduced by appropriate premedication and interstitial pneumonitis. Hypersensitivity reactions are less frequent than with paclitaxel. Docetaxel has shown a survival and quality of life advantage as a single agent first- and second-line versus placebo, as well as first-line in a platinum-based doublet therapy compared to a single agent. Increasingly docetaxel has also been used effectively in adjuvant regimens in earlier stages of the disease. Future areas of research include combinations with novel targeted therapies, and a greater understanding of biomarkers that might help predict efficacy and personalize therapy.

The effects of mixed MPEG-PLA/Pluronic copolymer micelles on the bioavailability and multidrug resistance of docetaxel

A mixed micelle that comprised of MPEG-PLA (MPP) and Pluronic copolymers was developed for enhanced bioavailability and to overcome multidrug resistance of docetaxel in cancer therapy. The mixed micelles that sufficiently solubilized docetaxel were evaluated for the effect of Pluronic copolymers weight ratio on the mixed micelles with respect to drug loading and drug release. In vitro, cell viability and cytotoxicity studies in KB and KBv cells revealed that the mixed micellar formulations were more potent than the commercial docetaxel formulation (Taxotere). In vivo pharmacokinetics study in rats showed that the mixed micelles significantly enhanced the bioavailability of docetaxel (3.6 fold) than Taxotere. Moreover, antitumor activity assessed in KBv cancer xenograft BALB/C nude mice models showed that the mixed micelles significantly reduced the tumor size than the control (Taxotere). Clear differences in the intracellular uptake of docetaxel between MPP and mixed micelles were observed using confocal laser scanning microscopy. This study presents not only a new micelle structure for a diblock-triblock copolymer system, but also a method for enhanced bioavailability of docetaxel and to overcome some of the limitations on its multidrug resistance in cancer therapy.