Taxanes: an overview of the pharmacokinetics and pharmacodynamics

Oral antivirals for COVID-19 among patients with cancer

PURPOSE

Immunocompromised individuals, such as those diagnosed with cancer, are at a significantly higher risk for severe illness and mortality when infected with SARS-CoV-2 (COVID-19) than the general population. Two oral antiviral treatments are approved for COVID-19: Paxlovid® (nirmatrelvir/ritonavir) and Lagevrio® (molnupiravir). There is a paucity of data regarding the benefit from these antivirals among immunocompromised patients with cancer, and recent studies have questioned their efficacy among vaccinated patients, even those with risk factors for severe COVID-19.

METHODS

We evaluated the efficacy and safety of nirmatrelvir/ritonavir and molnupiravir in preventing severe illness and death using our database of 457 patients with cancer and COVID-19 from Brown University-affiliated hospitals.

RESULTS

Sixty-seven patients received nirmatrelvir/ritonavir or molnupiravir and were compared to 45 concurrent controls who received no antiviral treatment despite being eligible to receive it. Administration of nirmatrelvir/ritonavir or molnupiravir was associated with improved survival and lower 90-day all-cause and COVID-19-attributed mortality (p < 0.05) and with lower peak O2 requirements (ordinal odds ratio [OR] 1.52, 95% confidence interval [CI] 0.92-2.56).

CONCLUSION

Acknowledging the small size of our sample as a limitation, we concluded that early antiviral treatment might be beneficial to immunocompromised individuals, particularly those with cancer, when infected with SARS-CoV-2. Larger-scale, well-stratified studies are needed in this patient population.

Clinical Benefit from Docetaxel +/- Ramucirumab Is Not Associated with Mutation Status in Metastatic Non-Small-Cell Lung Cancer Patients Who Progressed on Platinum Doublets and Immunotherapy

Docetaxel +/- ramucirumab remains the standard-of-care therapy for patients with metastatic non-small-cell lung cancer (NSCLC) after progression on platinum doublets and immune checkpoint inhibitors (ICIs). The aim of our study was to investigate whether the cancer gene mutation status was associated with clinical benefits from docetaxel +/- ramucirumab. We also investigated whether platinum/taxane-based regimens offered a better clinical benefit in this patient population. A total of 454 patients were analyzed (docetaxel +/- ramucirumab n=381; platinum/taxane-based regimens n=73). Progression-free survival (PFS) and overall survival (OS) were compared among different subpopulations with different cancer gene mutations and between patients who received docetaxel +/- ramucirumab versus platinum/taxane-based regimens. Among patients who received docetaxel +/- ramucirumab, the top mutated cancer genes included TP53 (n=167), KRAS (n=127), EGFR (n=65), STK11 (n=32), ERBB2 (HER2) (n=26), etc. None of these cancer gene mutations or PD-L1 expression was associated with PFS or OS. Platinum/taxane-based regimens were associated with a significantly longer mQS (13.00 m, 95% Cl: 11.20-14.80 m versus 8.40 m, 95% Cl: 7.12-9.68 m, LogRank P=0.019) than docetaxel +/- ramcirumab. Key prognostic factors including age, histology, and performance status were not different between these two groups. In conclusion, in patients with metastatic NSCLC who have progressed on platinum doublets and ICIs, the clinical benefit from docetaxel +/- ramucirumab is not associated with the cancer gene mutation status. Platinum/taxane-based regimens may offer a superior clinical benefit over docetaxel +/- ramucirumab in this patient population.

Anticancer Effect by Combined Treatment of Artemisia annua L. Polyphenols and Docetaxel in DU145 Prostate Cancer Cells and HCT116 Colorectal Cancer Cells

Docetaxel (DTX), a semi-synthetic analogue of paclitaxel (taxol), is known to exert potent anticancer activity in various cancer cells by suppressing normal microtubule dynamics. In this study, we examined how the anticancer effect of DTX is regulated by polyphenols extracted from Korean Artemisia annua L. (pKAL) in DU145 prostate cancer cells (mutant p53) and HCT116 colorectal cancer cells (wild-type p53). Here, we show that the anticancer effect of DTX was enhanced more significantly by pKAL in HCT116 cells than in DU145 cells via phase-contrast microscopy, CCK-8 assay, Western blot, and flow cytometric analysis of annexin V/propidium iodide-stained cells. Notably, mutant p53 was slightly downregulated by single treatment of pKAL or DTX in DU145 cells, whereas wild-type p53 was significantly upregulated by pKAL or DTX in HCT116 cells. Moreover, the enhanced anticancer effect of DTX by pKAL in HCT116 cells was significantly associated with the suppression of DTX-induced p53 upregulation, increase of DTX-induced phospho-p38, and decrease of DTX-regulated cyclin A, cyclin B1, AKT, caspase-8, PARP1, GM130, NF-κB p65, and LDHA, leading to the increased apoptotic cell death and plasma membrane permeability. Our results suggest that pKAL could effectively improve the anticancer effect of DTX-containing chemotherapy used to treat various cancers expressing wild-type p53.

Oral antivirals for COVID-19 among patients with cancer

Purpose

Immunocompromised individuals, such as those diagnosed with cancer, are at a significantly higher risk for severe illness and mortality when infected with SARS-CoV-2 (COVID-19) than the general population. Two oral antiviral treatments are approved for COVID-19: Paxlovid® (nirmatrelvir/ritonavir) and Lagevrio® (molnupiravir). There is a paucity of data regarding the benefit from these antivirals among immunocompromised patients with cancer, and recent studies have questioned their efficacy among vaccinated patients, even those with risk factors for severe COVID-19.

Methods

We evaluated the efficacy and safety of nirmatrelvir/ritonavir and molnupiravir in preventing severe illness and death using our database of 457 patients with cancer and COVID-19 from Brown University-affiliated hospitals. 67 patients received nirmatrelvir/ritonavir or molnupiravir and were compared to 56 concurrent controls who received no antiviral treatment despite being eligible to receive it.

Results

Administration of nirmatrelvir/ritonavir or molnupiravir was associated with improved survival and lower 90-day all-cause and COVID-19-attributed mortality (p<0.05) and with lower peak O2 requirements (ordinal odds ratio [OR] 1.52, 95% confidence interval [CI] 0.92-2.56).

Conclusion

Acknowledging the small size of our sample as a limitation, we concluded that early antiviral treatment might be beneficial to immunocompromised individuals, particularly those with cancer, when infected with SARS-CoV-2. Larger-scale, well-stratified studies are needed in this patient population.

Design of carboxymethylcellulose-conjugated polymeric prodrug micelles for enhanced in vivo performance of docetaxel

Docetaxel (DTX) has become one of the most important cytotoxic drugs to treat cancer; nevertheless, its poor hydrophilicity and non-specific distribution of DTX lead to detrimental side effects. In this article, we devised carboxymethylcellulose (CMC)-conjugated polymeric prodrug micelles (mPEG-CMC-DTX PMs) for DTX delivery. The ester-bonded polymeric prodrug, mPEG-CMC-DTX, was synthesized and exhibited the capacity for self-assembling into polymeric micelles. The CMC is profusely substituted and acetylated to promote the coupling rate of DTX. Covalent binding of DTX and CMC through an ester bond can be hydrolyzed to dissociate the bond under the action of esterase in the tumor. The mPEG-CMC-DTX PMs displayed promoted drug loading (>50 %, wt), commendable stability, and sustained release behavior in vitro. The gradual release of the prodrug amplified the selectivity of cytotoxicity between normal cells and tumor cells, mitigating the systemic toxicity of mPEG-CMC-DTX PMs and enabling dose intensification. Notably, mPEG-CMC-DTX PMs demonstrated a superior antitumor efficacy and low systemic toxicity due to the elevated tolerance dosage (even at 40 mg/kg DTX). In summation, mPEG-CMC-DTX PMs harmonized the antitumor efficacy and toxicity of DTX. In essence, innovative perspectives for the rational design of CMC-conjugated polymeric prodrug micelles for the delivery of potently toxic drugs were proffered.

X-Box Binding Protein 1 (XBP1): A Potential Role in Chemotherapy Response, Clinical Pathologic Features, Non-Inflamed Tumour Microenvironment for Breast Cancer

X-box binding protein 1 (XBP1) is mainly expressed in breast cancer (BC) in human cancers. Its tumorigenesis and favourable prognosis are contradictory, and its essential role in chemotherapeutic response and immunosuppression is unknown in BC. The study firstly identified XBP1 who received neoadjuvant chemotherapy (NAC) from GSE25055 and GSE24460. Associations between XBP1 expression and clinicopathological characteristics was investigated using Oncomine, TCGA, UALCAN and bc-GenExMiner. The prognostic value of XBP1 was assessed using the Kaplan–Meier Plotter, bc-GenExMiner, GSE25055, and GSE25056. Furthermore, we systematically correlated XBP1 and immunological characteristics in the BC tumour microenvironment (TME) using TISIDB, TIMER, GSE25055, GSE25056 and TCGA dataset. Finally, an essential role of XBP1 in chemotherapy response was evaluated based on GSE25055, GSE25065, GSE24460, GSE5846, ROC Plotter and CELL databases. Furthermore, XBP1 mRNA expression levels were obviously highest in BC among human cancers and were significantly related to a good prognosis. In addition, XBP1 mRNA and protein levels were higher in the luminal subtype than in normal tissues and basal-like subtype, which might be attributed to membrane transport-related processes. Apart from BC, negative immunological correlations of XBP1 were not observed in other malignancies. XBP1 might shape the non-inflamed TME in BC. Finally, XBP1 expression was higher in chemo-resistive than chemo-sensitive cases, it had a predictive value and could independently predict chemotherapy response in BC patients receiving NAC. Our study suggests that the essential role of XBP1 in clinical pathologic features, non-inflamed TME, chemotherapy response in BC.

Probing the new strategy for the oral formulations of taxanes: changing the method with the situation

The first-generation taxanes (including paclitaxel and docetaxel) are widely used for the treatment of various cancers in clinical settings. In the past decade, a series of new-generation taxanes have been developed which are effective in the inhibition of tumor resistance. However, intravenous (i.v.) infusion is still the only route of administration, and may result in serious adverse reactions with respect to the utilization of Cremophor EL or Tween-80 as solvent. Besides, the dosing schedule is also limited. Therefore, oral administration of taxanes is urgently needed to avoid the adverse reactionss and increase dosing frequency. In this review, we first outlined the discovery and development of taxane-based anticancer agents. Furthermore, we summarized the research progress on the oral formulations of taxanes and proposed some thoughts on the future development of oral taxane formulations.

Stimulus-responsive liposomes for biomedical applications

Liposomes are amphipathic lipidic supramolecular aggregates that are able to encapsulate and carry molecules of both hydrophilic and hydrophobic nature. They have been widely used as in vivo drug delivery systems for some time because they offer features such as synthetic flexibility, biodegradability, biocompatibility, low immunogenicity, and negligible toxicity. In recent years, the chemical modification of liposomes has paved the way to the development of smart liposome-based drug delivery systems, which are characterized by even more tunable and disease-directed features. In this review, we highlight the different types of chemical modification introduced to date, with a particular focus on internal stimuli-responsive liposomes and prodrug activation.

The Effect of Bitter Melon (Momordica charantia) Extract on the Uptake of 99mTc Labeled Paclitaxel: In Vitro Monitoring in Breast Cancer Cells

Background:

Bitter Melon Extract (BME) is widely used for the treatment of various diseases worldwide due to its rich phytochemical and antioxidant content. The well-known anti-cancer drug Paclitaxel (PAC) plays a major role in the treatment of various cancer types such as ovarian, breast, and lung cancer. Technetium-99m (99mTc) radiolabeled paclitaxel is emerging as an imaging probe for breast cancer in vivo. 99mTc labeled compounds have been attracting more scientific attention since the achievement of earlier researches in Nuclear Medicine. People consume several types of diets of plant origin without knowing the interaction with radiolabeled compounds or radiopharmaceuticals.

Objectives:

In the current study, we aimed to monitor the potential effects of the BME on the uptake of 99mTc labeled Paclitaxel (99mTc-PAC) against MCF-7 (ER+) and MDA-MB-231 (ER-) cell lines by using in vitro methods.

Methods:

BME was obtained by the extraction of BM seeds by 80% ethanol. PAC was labeled with 99mTc by stannous chloride (SnCl2) as a reducing agent. Cytotoxicity and incorporation assays were performed on MCF-7 and MDA-MB-231 cells within the cell culture studies.

Results:

The uptake value of 99mTc-PAC on MCF-7 cells at 240 minutes was 6.20% and BME treated 99mTc- PAC value was 17.39%.

Conclusion:

It is observed that BME treatment has a significant effect on the uptake of 99mTc-PAC on MCF-7 cells which is a known estrogen receptor-positive breast carcinoma cell line. It is concluded that this effect could be due to the estrogen receptor-dependent interaction of BME.

Long non-coding RNA SNHG6 regulates the sensitivity of prostate cancer cells to paclitaxel by sponging miR-186

Background

Chemo-resistance is one of the main obstacles in the treatment of prostate cancer (PCa). Long non-coding RNA small nucleolar RNA host gene 6 (SNHG6) is involved in the chemo-resistance of various tumors. We aim to survey the role and underlying molecular mechanism of SNHG6 in PCa resistance to paclitaxel (PTX).

Methods

The expression of SNHG6 and miR-186 was detected using quantitative real time polymerase chain reaction (qRT-PCR). The proliferation, migration, invasion, and apoptosis of PTX-resistant PCa cells were determined via 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT), transwell assay, or flow cytometry assay. Protein levels of CyclinD1, matrix metalloproteinase 9 (MMP9), Vimentin, E-cadherin, Cleaved-caspase-3 (Cleaved-casp-3) Cleaved-caspase-9 (Cleaved-casp-9), Multidrug Resistance associated Protein 1 (MRP1), and multidrug resistance-1 (MDR1) were assessed by western blot analysis. The relationship between SNHG6 and miR-186 were confirmed by dual-luciferase reporter assay. The role of SNHG6 in vivo was confirmed by xenograft tumor model.

Results

SNHG6 expression was increased and miR-186 expression was reduced in drug-resistant PCa tissues and cells. SNHG6 knockdown elevated PTX-resistant PCa cells sensitivity to PTX in vitro and in vivo, and repressed proliferation, migration, and invasion of PTX-resistant PCa cells in vitro. Importantly, SNHG6 acted as a sponge of miR-186. Furthermore, miR-186 downregulation reversed SNHG6 silencing-mediated cell sensitivity to PTX, proliferation, migration, and invasion in PTX-resistant PCa cells.

Conclusions

SNHG6 knockdown elevated the sensitivity of PTX-resistant PCa cells to PTX by sponging miR-186, indicating that SNHG6 might be a therapeutic target for PCa.

The Effect of Nail Lacquer on Taxane-Induced Nail Changes in Women With Breast Cancer

Objective

Taxane-induced nail changes are considered as an important cosmetic manifestation with an incidence that reaches up to 44% of patients treated with taxane-included therapeutic regimens. In this article, we represent a clinical observational study to evaluate the effect of cosmetic nail lacquer on taxane-induced nail changes in female patients diagnosed with breast cancer.

Methods

Prospectively, we identified those women who were diagnosed with breast cancer, scheduled to have AC-Taxol protocol. Any female with previous dermatological or systemic disorders that affect nails was excluded from the study. Patients were categorized into 2 groups based on the utilization of nail lacquer. The first group includes women who started to use the nail lacquer after development of nail changes. The second group comprises those women who did not use the nail lacquer at any occasion.

Results

A total of 59 female patients were included in the study; 46 (78%) of them developed nail changes and the main change was nail discoloration. The first group which has used nail lacquer (17, 28.8%) showed an improvement among 15 (78.9%) patients, whereas 2 (7.4%) of them continued to have worsening symptoms. On the contrary, most of the second group (25, 92.9%) did not show any improvement in nail changes. A statistical significance between the tested groups was observed (P = .000). There is no statistical association between the progression of nail changes and the age of patients.

Conclusions

Taxane-induced nail changes are considered as an important clinical, cosmetic, and psychological complication, especially for female patients with cancer. This article suggests that nail lacquer may have an effect in the improvement of nail changes, especially nail discoloration. Further investigations are recommended to prove the efficacy of nail lacquer.

ABCB1 and ERCC1 gene polymorphisms are associated with nephro- and hepatotoxicity to carboplatin/paclitaxel-based chemotherapy in patients with gynecologic cancers

BACKGROUND

Paclitaxel/carboplatin combination is the standard chemotherapeutic protocol for gynecologic cancers, but severe toxicities may compromise treatment. There is great inter-individual variability regarding the incidence and severity of toxicities, which may be due to single-nucleotide polymorphisms (SNPs) affecting drug disposition or cellular sensitivity. Here we investigate the impact of selected SNPs in ERCC1, ABCB1, CYP2C8, and CYP3A5 genes on the incidence of severe toxicities, including nephro- and hepatotoxicity.

METHODS

A cohort of 507 gynecological cancer patients receiving paclitaxel/carboplatin was recruited at the Brazilian National Cancer Institute (INCA-Brazil). Clinical data were obtained during routine consultations or from electronic medical records. Toxicities were graded according to the Common Terminology Criteria for Adverse Events (CTCAE 5.0). Genotyping was performed using real-time PCR.

RESULTS

ABCB1 c.1236C>T was associated with moderate-to-severe (grades 2-4) nephrotoxicity (OR_adjusted 2.40; 95% CI 1.39-4.15), even after adjustment for age (≥ 65) and diabetes. The risk association between ABCB1 c.1236C>T and moderate-to-severe nephrotoxicity following paclitaxel/carboplatin chemotherapy was also present among non-diabetic patients (OR_adjusted 2.16; 95% CI 1.22-3.82). ERCC1 c.118C>T was the only individual variable associated with an increased risk for moderate-to-severe (grades 2-4) hepatotoxicity (OR 3.71; 95% CI 1.08-12.77), severe nausea (OR 4.18; 95% CI 1.59-10.95), and severe myalgia (OR 1.95; 95% CI 1.12-3.40).

CONCLUSIONS

ABCB1 c.1236C>T and ERCC1 c.118C>T might serve as potential biomarkers for the risk of moderate-to-severe toxicities to carboplatin/paclitaxel chemotherapy of gynecological cancers.

Nanopaclitaxel therapy: an evidence based review on the battle for next-generation formulation challenges

The poor solubility of paclitaxel (PTX), the most commonly used anticancer drug (Taxol^®), has long hindered the development of successful formulations. In 2005, the launch of Abraxane^®, a human albumin-based preparation of PTX, competed with Taxol^® in the commercial market. The success of Abraxane pushed other generic preparations aside, sparking competition among the global pharmaceutical companies to develop the novel and superior PTX nanotechnology-driven formulations. Unsurprisingly, the success underlying with cancer treatment using nano PTX therapy has now entered into a new era of drug development, patentability, preclinical and clinical evaluation, leading eventually to a significant increase in the regulatory approval of the products. The present article aims to provide recent progress in the development of nano PTX formulations by various pharmaceutical companies for safe and effective drug therapies for patients benefit.

Taxane Induced Cystoid Macular Edema: Case Report and Integrated Pathogenic Theory

PURPOSE

To report a case of a 73-year-old man who presented with decreased visual acuity due to bilateral macular edema after paclitaxel administration for prostate cancer.

METHODS

The ophthalmic evaluation consisted of medical and ocular history, Best Corrected Visual Acuity, slit-lamp biomicroscopy and Spectral-domain optical coherence tomography / Fluorescein Angiography.

RESULTS

Optical Coherence Tomography and Fluorescein Angiography revealed silent cystoid macular edema. After consulting with the oncologist, the cessation of paclitaxel therapy was decided. The patient presented a gradual but steady resumption of the retinal edema, with complete restoration of normal retinal morphology and function within two months. The pathogenesis of the silent Cystoid Macular Edema (CME) is still unclear. Based on our case and a critical review of the previous observations and published data, we propose that the underlying cause of Taxane induced CME is the functional failure of Aquaporin mediated water transport at the level of retinal Intermediate and Deep capillary plexuses, and at lesser extent at the level of the Retinal Pigment Epithelium.

CONCLUSION

Taxane induced silent CME should be attributed to the action of Taxanes on the microtubule guided aquaporin vesicles transport to the cell membrane. In our case of Taxane induced silent CME, withdrawal of the taxane was enough for complete recovery, and no additional treatment was needed.

Consequences of blunting the mevalonate pathway in cancer identified by a pluri-omics approach

We have previously shown that the combination of statins and taxanes was a powerful trigger of HGT-1 human gastric cancer cells’ apoptosis¹. Importantly, several genes involved in the “Central carbon metabolism pathway in cancer”, as reported in the Kyoto Encyclopedia of Genes and Genomes, were either up- (ACLY, ERBB2, GCK, MYC, PGM, PKFB2, SLC1A5, SLC7A5, SLC16A3,) or down- (IDH, MDH1, OGDH, P53, PDK) regulated in response to the drug association. In the present study, we conducted non-targeted metabolomics and lipidomics analyses by complementary methods and cross-platform initiatives, namely mass spectrometry (GC-MS, LC-MS) and nuclear magnetic resonance (NMR), to analyze the changes resulting from these treatments. We identified several altered biochemical pathways involved in the anabolism and disposition of amino acids, sugars, and lipids. Using the Cytoscape environment with, as an input, the identified biochemical marker changes, we distinguished the functional links between pathways. Finally, looking at the overlap between metabolomics/lipidomics and transcriptome changes, we identified correlations between gene expression modifications and changes in metabolites/lipids. Among the metabolites commonly detected by all types of platforms, glutamine was the most induced (6–7-fold), pointing to an important metabolic adaptation of cancer cells. Taken together, our results demonstrated that combining robust biochemical and molecular approaches was efficient to identify both altered metabolic pathways and overlapping gene expression alterations in human gastric cancer cells engaging into apoptosis following blunting the cholesterol synthesis pathway.

A rare cause of acute abdomen in the ED: Chemotherapy-induced pneumatosis intestinalis

Pneumatosis intestinalis (PI) and portomesenteric venous gas (PVG) refers to the presence of air within the intestinal wall and portomesenteric vessels. Most of the time, it is associated with mesenteric ischemia that requires immediate surgical intervention as it has high mortality rate. It may also be seen secondary to various conditions, including infections, surgeries, and some chemotherapeutic drugs. A 61-year old-male was admitted to our emergency department complaining of abdominal pain after chemotherapy. Radiological evaluation of the patient demonstrated massive PVG and PI. Patient underwent urgent surgery due to the possibility of intestinal ischemia and infarction, but no necrosis was identified Chemotherapeutic drug-induced PI and PVG was the final diagnosis. Although PI and PVG are signs of mesenteric ischemia and intestinal necrosis most the of time, chemotherapeutic drugs may also cause PI and PVG rarely. Recent history of chemotheraphy and absence of any mesenteric vascular occlusion may be the diagnostic clue.

Technetium-99m radiolabeled paclitaxel as an imaging probe for breast cancer in vivo

The high incidence and mortality of breast cancer supports efforts to develop innovative imaging probes to effectively diagnose, evaluate the extent of the tumor, and predict the efficacy of tumor treatments while concurrently and selectively delivering anticancer agents to the cancer tissue. In the present study we described the preparation of technetium-99m (99mTc)-labeled paclitaxel (PTX) and evaluated its feasibility as a radiotracer for breast tumors (4T1) in BALB/c mice. Thin Layer Chromatography (TLC) was used to determine the radiochemical purity and in vitro stability of 99mTc-PTX. PTX micelles showed a unimodal distribution with mean diameter of 13.46±0.06nm. High radiochemical purity (95.8±0.3%) and in vitro stability (over than 95%), up to 24h, were observed. Blood circulation time of 99mTc-PTX was determined in healthy BALB/c mice. 99mTc-PTX decays in a one-phase manner with a half-life of 464.3 minutes. Scintigraphic images and biodistribution were evaluated at 4, 8 and 24h after administration of 99mTc-PTX in 4T1 tumor-bearing mice. The data showed a significant uptake in the liver, spleen and kidneys, due to the importance of these routes for excretion. Moreover, high tumor uptake was achieved, indicated by high tumor-to-muscle ratios. These findings indicate the usefulness of 99mTc-PTX as a radiotracer to identify 4T1 tumor in animal models. In addition, 99mTc-PTX might be used to follow-up treatment protocols in research, being able to provide information about tumor progression after therapy.

Mass spectrometry in the pharmacokinetic studies of anticancer natural products

In the history of medicine, nature has represented the main source of medical products. Indeed, the therapeutic use of plants certainly goes back to the Sumerian and Hippocrates and nowadays nature still represents the major source for new drugs discovery. Moreover, in the cancer treatment, drugs are either natural compounds or have been developed from naturally occurring parent compounds firstly isolated from plants and microbes from terrestrial and marine environment. A critical element of an anticancer drug is represented by its severe toxicities and, after administration, the drug concentrations have to remain in an appropriate range to be effective. Anyway, the drug dosage defined during the clinical studies could be inappropriate for an individual patient due to differences in drug absorption, metabolism and excretion. For this reason, personalized medicine, based on therapeutic drug monitoring (TDM), represents one of most important challenges in cancer therapy. Mass spectrometry sensitivity, specificity and fastness lead to elect this technique as the Golden Standard for pharmacokinetics and drug metabolism studies therefore for TDM. This review focuses on the mass spectrometry-based methods developed for pharmacokinetic quantification in human plasma of anticancer drugs derived from natural sources and already used in clinical practice. Particular emphasis was placed both on the pre-analytical and analytical steps, such as: sample preparation procedures, sample size required by the analysis and the limit of quantification of drugs and metabolites to give some insights on the clinical practice applicability. © 2015 Wiley Periodicals, Inc. Mass Spec Rev. 36:213-251, 2017.

Docetaxel-loaded PLGA and PLGA-PEG nanoparticles for intravenous application: pharmacokinetics and biodistribution profile

Docetaxel is a highly potent anticancer agent being used in a wide spectrum of cancer types. There are important matters of concern regarding the drug’s pharmacokinetics related to the conventional formulation. Poly(lactide-co-glycolide) (PLGA) is a biocompatible/biodegradable polymer with variable physicochemical characteristics, and its application in human has been approved by the United States Food and Drug Administration. PLGA gives polymeric nanoparticles with unique drug delivery characteristics. The application of PLGA nanoparticles (NPs) as intravenous (IV) sustained-release delivery vehicles for docetaxel can favorably modify pharmacokinetics, biofate, and pharmacotherapy of the drug in cancer patients. Surface modification of PLGA NPs with poly(ethylene glycol) (PEG) can further enhance NPs’ long-circulating properties. Herein, an optimized fabrication approach has been used for the preparation of PLGA and PLGA–PEG NPs loaded with docetaxel for IV application. Both types of NP formulations demonstrated in vitro characteristics that were considered suitable for IV administration (with long-circulating sustained-release purposes). NP formulations were IV administered to an animal model, and docetaxel’s pharmacokinetic and biodistribution profiles were determined and compared between study groups. PLGA and PEGylated PLGA NPs were able to modify the pharmacokinetics and biodistribution of docetaxel. Accordingly, the mode of changes made to pharmacokinetics and biodistribution of docetaxel is attributed to the size and surface properties of NPs. NPs contributed to increased blood residence time of docetaxel fulfilling their role as long-circulating sustained-release drug delivery systems. Surface modification of NPs contributed to more pronounced docetaxel blood concentration, which confirms the role of PEG in conferring long-circulation properties to NPs.

Uncommon Adverse Effects of Commonly Used Chemotherapeutic Agents in Medical Oncology Practice: A Series of Two Cases of Hand-Foot Syndrome

Chemotherapy has an increasing potential for cure and palliation of most forms of cancer in different stages. However, its use is associated with a multitude of side effects some very common and few very rare. We present two patients of metastatic nonsmall lung cancer who had severe forms of hand-foot syndrome with two different classes of antineoplastic drugs and have to discontinue chemotherapy.

Efficient Red Light Photo-Uncaging of Active Molecules in Water Upon Assembly into Nanoparticles

We introduce a means of efficiently photo-uncaging active compounds from amino-1,4-benzoquinone in aqueous environments. Aqueous photochemistry of this photocage with one-photon red light is typically not efficient unless the photocaged molecules are allowed to assemble into nanoparticles. A variety of biologically active molecules were functionalized with the photocage and subsequently formulated into water-dispersible nanoparticles. Red light irradiation through various mammalian tissues achieved efficient photo-uncaging. Co-encapsulation of NIR fluorescent dyes and subsequent photomodulation provides a NIR fluorescent tool to assess both particle location and successful photorelease.

Brassinin inhibits STAT3 signaling pathway through modulation of PIAS-3 and SOCS-3 expression and sensitizes human lung cancer xenograft in nude mice to paclitaxel

Persistent phosphorylation of signal transducers and activators of transcription 3 (STAT3) is frequently observed in tumor cells. We found that brassinin (BSN) suppressed both constitutive and IL-6-inducible STAT3 activation in lung cancer cells. Moreover, BSN induced PIAS-3 protein and mRNA, whereas the expression of SOCS-3 was reduced. Knockdown of PIAS-3 by small interfering RNA prevented inhibition of STAT3 and cytotoxicity by BSN. Overexpression of SOCS-3 in BSN-treated cells increased STAT3 phosphorylation and cell viability. BSN down-regulated STAT3-regulated gene products, inhibited proliferation, invasion, as well as induced apoptosis. Most importantly, when administered intraperitoneally, combination of BSN and paclitaxel significantly decreased the tumor development in a xenograft lung cancer mouse model associated with down-modulation of phospho-STAT3, Ki-67 and CD31. We suggest that BSN inhibits STAT3 signaling through modulation of PIAS-3 and SOCS-3, thereby attenuating tumor growth and increasing sensitivity to paclitaxel.

Paclitaxel Through the Ages of Anticancer Therapy: Exploring Its Role in Chemoresistance and Radiation Therapy

Paclitaxel (Taxol^®) is a member of the taxane class of anticancer drugs and one of the most common chemotherapeutic agents used against many forms of cancer. Paclitaxel is a microtubule-stabilizer that selectively arrests cells in the G2/M phase of the cell cycle, and found to induce cytotoxicity in a time and concentration-dependent manner. Paclitaxel has been embedded in novel drug formulations, including albumin and polymeric micelle nanoparticles, and applied to many anticancer treatment regimens due to its mechanism of action and radiation sensitizing effects. Though paclitaxel is a major anticancer drug which has been used for many years in clinical treatments, its therapeutic efficacy can be limited by common encumbrances faced by anticancer drugs. These encumbrances include toxicities, de novo refraction, and acquired multidrug resistance (MDR). This article will give a current and comprehensive review of paclitaxel, beginning with its unique history and pharmacology, explore its mechanisms of drug resistance and influence in combination with radiation therapy, while highlighting current treatment regimens, formulations, and new discoveries.

Treatment regimens of classical and newer taxanes

The classical taxanes (paclitaxel, docetaxel), the newer taxane cabazitaxel and the nanoparticle-bound nab-paclitaxel are among the most widely used anticancer drugs. The taxanes share the characteristics of extensive hepatic metabolism and biliary excretion, the need for dose adaptation in patients with liver dysfunction, and a substantial pharmacokinetic variability even after taking into account known covariates. Data from clinical studies suggest that optimal scheduling of the taxanes is dependent not only on the specific taxane compound, but also on the tumor type and line of treatment. Still, the optimal dosing regimen (weekly vs 3 weekly) and optimal dose of the taxanes are controversial, as is the value of pharmacological personalization of taxane dosing. In this article, an overview is given on the pharmacological properties of the taxanes, including metabolism, pharmacokinetics-pharmacodynamics and aspects in the clinical use of taxanes. The latter includes the ongoing debate on the most active and safe regimen, the recommended initial dose and the issue of therapeutic drug dosing.

Zerumbone inhibits growth of hormone refractory prostate cancer cells by inhibiting JAK2/STAT3 pathway and increases paclitaxel sensitivity

Zerumbone, a phytochemical isolated from Zingiber zerumbet has been shown previously to exhibit antineoplastic activity. But, the effect of zerumbone in prostate cancer has not been evaluated. Prostate cancer is frequently associated with elevated levels of interleukin-6 (IL-6), which exerts its oncogenic effects through activation of Janus kinase 2 (JAK2) followed by activation of the transcription factor STAT3 (signal transducer and activator of transcription 3). Here, we investigated whether the anticancer effects of zerumbone are mediated through inhibition of the JAK2/STAT3 signaling pathway and whether zerumbone can increase the paclitaxel (PTX) sensitivity of prostate cancer cells. Zerumbone exerted significant cytotoxicity of DU145 versus PC3 prostate cancer cells through cell cycle arrest at G0/G1 phase followed by apoptosis. Zerumbone selectively inhibited JAK2 in both DU145 and PC3 cells. However, the biological axis of IL-6/JAK2/STAT3 was inhibited only in DU145 cells as no STAT3 phosphorylation was detected in PC3 cells even after IL-6 stimulation. Other signaling pathways in DU145 cells remained unaffected. The expression of prostate cancer-associated genes, including cyclin D1, IL-6, COX2, and ETV1, was blocked. Zerumbone also synergistically increased the sensitivity to PTX. Further preclinical study might reveal the potential use of zerumbone as a chemotherapeutic agent for hormone refractory prostate cancer where IL-6/JAK2/STAT3 signaling is aberrantly active and may be combined with PTX.

Quantification of taxanes in biological matrices: a review of bioanalytical assays and recommendations for development of new assays

Since the isolation of paclitaxel and its approval for the treatment of breast cancer, various taxanes and taxane formulations have been developed. To date, almost 100 bioanalytical assays have been published with the method development and optimization often extensively discussed by the authors. This Review presents an overview of assays published between January 1970 and September 2013 that described method development and validation of assays used to quantify taxanes in biological matrices such as plasma, urine, feces and tissue samples. For liquid chromatography assays, sample pretreatment, chromatographic separation and assay performance are compared. Since this Review discusses the limitations of previously developed liquid chromatography assays and gives recommendations for future assay development, it can be used as a reference for future development of liquid chromatography assays for the quantification of taxanes in various biological matrices to support preclinical and clinical studies.

The Role of Chemotherapy in the Treatment of Malignant Astrocytomas

Malignant astrocytomas are aggressive neoplasms with a dismal prognosis despite optimal treatment. Maximal resective surgery is traditionally complemented by radiation therapy. Chemotherapy is now used on patients as initial therapy when their functional status is congruent with further treatment. The classic agents used are nitrosoureas, but temozolomide has taken the front seat recently, with recent data demonstrating increased survival when this agent is used concurrently with radiation therapy in newly diagnosed glioblastoma patients. A new class of agents, refered to as biological modifiers, are increasingly used in clinical trials in an effort to affect the intrinsic biologic aberrations harboured by tumor cells. These drugs comprise differentiation agents, anti-angiogenic agents, matrix-metalloproteinase inhibitors and signal transduction inhibitors, among others. This article reviews the standard cytotoxic agents that have been used to treat malignant astrocytomas, and the different combination regimens offering promise. In addition, recent advances with biological modifiers are also discussed.

Metabolism of the taxanes including nab-paclitaxel

INTRODUCTION

The classical taxanes (paclitaxel, docetaxel), the newer taxane cabazitaxel and the nanoparticle-bound nab-paclitaxel are among the most widely used anticancer drugs. Despite years of research, the optimal dosing regimen (weekly vs 3-weekly) and optimal dose is still controversial, as is the value of pharmacological personalization of taxane dosing.

AREAS COVERED

This review provides an overview of the pharmacological properties of the taxanes, including metabolism, pharmacokinetics-pharmacodynamics and aspects in the clinical use of taxanes. The latter includes the ongoing debate on the most active and safe regimen (paclitaxel, docetaxel, nab-paclitaxel), the recommended initial dose (cabazitaxel) and pharmacological dosing individualization.

EXPERT OPINION

Taxanes share the characteristics of extensive hepatic metabolism and biliary excretion, the need for dose adaptation in patients with liver dysfunction, and substantial pharmacokinetic variability even after taking into account known covariates. Data from clinical studies suggest that optimal scheduling of the taxanes is dependent not only on the specific taxane compound, but also on the tumor type and line of treatment. Finally, treating oncologists should be aware of the substantial risk for drug-drug interactions that is a direct consequence of the complex hepatic metabolism of the taxanes.

Characterization of in vitro metabolites of TM-2, a potential antitumor drug, in rat, dog and human liver microsomes using liquid chromatography/tandem mass spectrometry

RATIONALE

TM-2 (13-(N-Boc-3-i-butylisoserinoyl-4,10-β-diacetoxy-2-α-benzoyloxy-5-β,20-epoxy-1,13-α-dihydroxy-9-oxo-19-norcyclopropa[g]tax-11-ene) is a novel semi-synthetic taxane derivative. Our previous study demonstrated that it is a promising taxane derivative. The in vitro comparative metabolic profile of a drug between animals and humans is a key issue that should be investigated at early stages of drug development to better select drug candidates. In this study, the in vitro metabolic pathways of TM-2 in rat, dog and human liver microsomes were established and compared.

METHODS

TM-2 was incubated with liver microsomes in the presence of NADPH. Two different types of mass spectrometers - a hybrid linear trap quadrupole orbitrap (LC/LTQ-Orbitrap) mass spectrometer and a triple-quadrupole tandem mass spectrometer (LC/QqQ) were employed to acquire structural information of TM-2 metabolites. Accurate mass measurement using LC/LTQ-Orbitrap was used to determine the accurate mass data and elemental compositions of metabolites thereby confirming the proposed structures of the metabolites. For the chemical inhibition study, selective P450 inhibitors were added to incubations to initially characterize the cytochrome P450 (CYP) enzymes involved in the metabolism of TM-2.

RESULTS

A total of 12 components (M1-M12) were detected and identified as the metabolites of TM-2 in vitro. M1-M5 were formed by hydroxylation of the taxane ring or the lateral chain. Hydroxylated products can be further oxidized to the dihydroxylated metabolites M6-M10. M11 was a trihydroxylated metabolite. M12 was tentatively identified as a carboxylic acid derivative. The metabolism of TM-2 is much the same in all three species with some differences. The chemical inhibition study initially demonstrated that the formation of M2, the major metabolite of TM-2, is mainly mediated by CYP3A4.

CONCLUSIONS

Hydroxylation is the major biotransformation of the TM-2 pathway in vitro. CYP3A4 may play a dominant role in the formation of M2 in liver microsomes. The knowledge of the metabolic pathways of TM-2 is important to support further research of TM-2.

Nurse self-evaluation of assessment of chemotherapy-induced peripheral neuropathy in patients with cancer

The focus of this study was to assess the feasibility and clinical implementation of a standardized assessment for chemotherapy-induced peripheral neuropathy (CIPN) by registered nurses in patients undergoing neurotoxic chemotherapy. A total of 24 registered nurses from 4 different institutions were enrolled into the study. A pre- and posttest design was used to assess changes in nurses’ attitudes, knowledge, and perceived skill in CIPN assessment. Using selected data collection instruments, nurses performed standardized assessments during the course of chemotherapy treatments. Patient-reported symptoms, vibratory sensation, deep-tendon reflexes, and touch were collected at three time points during chemotherapy treatment. Results indicated there was no statistically significant change in knowledge of chemotherapy-induced peripheral neuropathy from baseline to the end of the study. However, this finding may be due to poor internal consistency noted among the items of the Nurse Knowledge and Attitudes CIPN Assessment. Implementation of a standardized subjective and objective nursing assessment of CIPN was feasible with a total mean feasibility score of 3.76 (range 0–5) with each individual item scoring between 3.35 and 3.91. The intervention did improve pretest and posttest confidence in performing assessment for CIPN (p = .003).

Oral co-administration of elacridar and ritonavir enhances plasma levels of oral paclitaxel and docetaxel without affecting relative brain accumulation

Background:

The intestinal uptake of the taxanes paclitaxel and docetaxel is seriously hampered by drug efflux through P-glycoprotein (P-gp) and drug metabolism via cytochrome P450 (CYP) 3A. The resulting low oral bioavailability can be boosted by co-administration of P-gp or CYP3A4 inhibitors.

Methods:

Paclitaxel or docetaxel (10 mg/kg) was administered to CYP3A4-humanised mice after administration of the P-gp inhibitor elacridar (25 mg kg⁻¹) and the CYP3A inhibitor ritonavir (12.5 mg kg⁻¹). Plasma and brain concentrations of the taxanes were measured.

Results:

Oral co-administration of the taxanes with elacridar increased plasma concentrations of paclitaxel (10.7-fold, P<0.001) and docetaxel (four-fold, P<0.001). Co-administration with ritonavir resulted in 2.5-fold (paclitaxel, P<0.001) and 7.3-fold (docetaxel, P<0.001) increases in plasma concentrations. Co-administration with both inhibitors simultaneously resulted in further increased plasma concentrations of paclitaxel (31.9-fold, P<0.001) and docetaxel (37.4-fold, P<0.001). Although boosting of orally applied taxanes with elacridar and ritonavir potentially increases brain accumulation of taxanes, we found that only brain concentrations, but not brain-to-plasma ratios, were increased after co-administration with both inhibitors.

Conclusions:

The oral availability of taxanes can be enhanced by co-administration with oral elacridar and ritonavir, without increasing the brain penetration of the taxanes.

Combined quantification of paclitaxel, docetaxel and ritonavir in human feces and urine using LC-MS/MS

A combined assay for the determination of paclitaxel, docetaxel and ritonavir in human feces and urine is described. The drugs were extracted from 200 μL urine or 50 mg feces followed by high-performance liquid chromatography analysis coupled with positive ionization electrospray tandem mass spectrometry. The validation program included calibration model, accuracy and precision, carry-over, dilution test, specificity and selectivity, matrix effect, recovery and stability. Acceptance criteria were according to US Food and Drug Administration guidelines on bioanalytical method validation. The validated range was 0.5-500 ng/mL for paclitaxel and docetaxel, 2-2000 ng/mL for ritonavir in urine, 2-2000 ng/mg for paclitaxel and docetaxel, and 8-8000 ng/mg for ritonavir in feces. Inter-assay accuracy and precision were tested for all analytes at four concentration levels and were within 8.5% and <10.2%, respectively, in both matrices. Recovery at three concentration levels was between 77 and 94% in feces samples and between 69 and 85% in urine samples. Method development, including feces homogenization and spiking blank urine samples, are discussed. We demonstrated that each of the applied drugs could be quantified successfully in urine and feces using the described assay. The method was successfully applied for quantification of the analytes in feces and urine samples of patients.

Phase II study of oral docetaxel and cyclosporine in canine epithelial cancer

The goal of the current study was to determine the efficacy of oral docetaxel in combination with cyclosporine in the treatment of canine epithelial cancer. Requirements for eligibility were histological confirmation of epithelial neoplasia, measurable disease, no chemotherapy treatment within 2 weeks, and a life expectancy of ≥ 3 months. Fifty-one dogs were enrolled. All dogs received 1.625 mg kg(-1) of docetaxel with 5 mg kg(-1) of cyclosporine (DT/CSA) by gavage. Ten dogs had progressive disease at 2 weeks, one dog died, and one dog was withdrawn from the study. Thirty-nine dogs were given a second dose of DT/CSA, three each receiving a third or fourth dose. Eight dogs had a dose reduction (1.5 mg kg(-1)) and six dogs had treatment delays primarily for gastrointestinal toxicity. The overall response rate was 16.7% (8/48 had a partial response there were no complete responses). The highest response rate was seen in dogs with oral squamous cell carcinoma (50%; 6/12).

NRF2 inhibition represses ErbB2 signaling in ovarian carcinoma cells: implications for tumor growth retardation and docetaxel sensitivity

NF-E2-related factor 2 (NRF2) is a transcription factor that regulates the expression of various antioxidant and detoxifying enzymes. Although the benefit of NRF2 in cancer prevention is well established, its role in cancer pathobiology was recently discovered. In this study, the role of NRF2 in tumor growth and docetaxel sensitivity was investigated in ErbB2-overexpressing ovarian carcinoma SKOV3 cells. Interfering RNA-mediated stable inhibition of NRF2 in SKOV3 cells repressed NRF2 signaling, resulting in cell growth arrest at G(0)/G(1) phase and tumor growth retardation in mouse xenografts. Microarray analysis revealed that ErbB2 expression is substantially reduced in NRF2-inhibited SKOV3 and this was further confirmed by RT-PCR and immunoblot analysis. Repression of ErbB2 led to a decrease in phospho-AKT and enhanced p27 protein, reinforcing the effect of NRF2 knockdown on SKOV3 growth. Furthermore, NRF2 inhibition-mediated ErbB2 repression increases the sensitivity of these cells to docetaxel cytotoxicity and apoptosis. The linkage between NRF2 and ErbB2 was confirmed in the ErbB2-positive breast cancer cell line BT-474: NRF2 knockdown suppressed ErbB2 expression and enhanced docetaxel sensitivity. Our results provide insight into the coordinated regulation of signaling molecules responding to environmental stress and suggest that NRF2 modulation might be a therapeutic strategy to limit tumor growth and enhance sensitivity to taxane-based chemotherapy.

In vitro assessment of cytochrome P450 inhibition and induction potential of felotaxel (SHR110008)

The purpose of this study was to assess the potential inhibitory and inductive effects of felotaxel on cytochrome P450 isozymes in vitro. The inhibitory effects of felotaxel on various CYP isozymes were determined in human liver microsomes. In addition, the ability of felotaxel to induce CYP enzymes in cultured human hepatocytes was evaluated. Results showed that felotaxel did not inhibit CYP1A2-, CYP2C9-, CYP2C19-, CYP2E1-, CYP2D6-, CYP2B6-, CYP2C8-, and mediated activities in human liver microsomes up to a concentration of 100 μM, while the inhibition (<30% inhibition) of CYP3A4 activities was observed at 100 μM felotaxel. In vitro felotaxel did not induce CYP1A2, CYP2C19, or CYP3A4/5 activities in cultured human hepatocytes. In present study, felotaxel has been identified as a potent inhibitor of metabolic activity of CYP3A4. Therefore, clinically relevant pharmacokinetic drug-drug interactions are likely to occur between felotaxel and co-administered substrates of these CYP3A4 isozymes. These findings provided some useful information for safe and effective use of felotaxel in clinical practice.

Abnormal muscle afferent function in a model of Taxol chemotherapy-induced painful neuropathy

Despite muscle pain being a well-described symptom in patients with diverse forms of peripheral neuropathy, the role of neuropathic mechanisms in muscle pain have received remarkably little attention. We have recently demonstrated in a well-established model of chemotherapy-induced painful neuropathy (CIPN) that the anti-tumor drug paclitaxel (Taxol) produces mechanical hyperalgesia in skeletal muscle, of similar time course to and with shared mechanism with cutaneous symptoms. In the present study, we evaluated muscle afferent neuron function in this rat model of CIPN. The mechanical threshold of muscle afferents in rats exposed to paclitaxel was not significantly different from the mechanical threshold of muscle afferents in control animals (P = 0.07). However, paclitaxel did produce a marked increase in the number of action potentials elicited by prolonged suprathreshold fixed intensity mechanical stimulation and a marked increase in the conduction velocity. In addition, the interspike interval (ISI) analysis (to evaluate the temporal characteristics of the response of afferents to sustained mechanical stimulation) showed a significant difference in rats treated with paclitaxel; there was a significantly greater ISI percentage of paclitaxel-treated muscle afferents with 0.01- and 0.02-s ISI. In contrast, an analysis of variability of neuronal firing over time (CV2 analysis) showed no effect of paclitaxel administration. These effects of paclitaxel on muscle afferent function contrast with the previously reported effects of paclitaxel on the function of cutaneous nociceptors.

Molecular targets of phytochemicals for cancer prevention

Although successful for a limited number of tumour types, the efficacy of cancer therapies, especially for late-stage disease, remains poor overall. Many have argued that this could be avoided by focusing on cancer prevention, which has now entered the arena of targeted therapies. During the process of identifying preventive agents, dietary phytochemicals, which are thought to be safe for human use, have emerged as modulators of key cellular signalling pathways. The task now is to understand how these chemicals perturb these pathways by modelling their interactions with their target proteins.

Palmar-plantar erythrodysesthesia secondary to docetaxel chemotherapy: a case report

Introduction

Docetaxel is a chemotherapeutic agent used alone or in combination for the management of many neoplastic conditions. Numerous side effects are well described as a consequence. Palmar-plantar erythrodysesthesia, although a relatively common side effect of some types of chemotherapy, occurs infrequently with docetaxel and is often attributed to other drug agents.

Case Presentation

We report the case of a 66-year-old Caucasian woman who received adjuvant docetaxel monotherapy for invasive breast cancer. She developed palmar-plantar erythrodysesthesia following her first cycle of treatment, which necessitated a change in management.

Conclusion

Palmar-plantar erythrodysesthesia is a relatively common side effect of cytotoxic chemotherapy, particularly with drugs such as 5-fluorouracil, capecitabine and liposomal doxorubicin. Docetaxel is commonly used both alone and in combination with a number of these agents for the management of various malignant conditions. We would like to highlight the occurrence of palmar-plantar erythrodysesthesia as a result of docetaxel monotherapy so that it can be considered as a potential cause in patients receiving combination treatment with chemotherapeutic agents better known to cause this toxicity.

Bioavailability of 99mTc-paclitaxel-glucuronide (99mTc-PAC-G)

An antitumor agent paclitaxel (PAC) has been proved to be efficient in the treatment of breast and ovarian cancer. Glucuronic acid-derived paclitaxel compound [paclitaxel-glucuronide (PAC-G)] was enzymatically synthesized using microsome preparate separated from rat livers. The biodistribution mechanism of PAC-G in healthy female Albino Wistar rats has been investigated. The expected structure is confirmed according to LC/MS results, and the possible attachment is to C2-hydroxyl group. PAC-G was labeled with 99mTc and the radiochemical yield of radiolabeled compound (99mTc-PAC-G) was 98.0±02.74 (n=9). The range of the breast/blood and breast/muscle ratios is approximately between 3 and 35 in 240ߙmin. All these experimental studies indicate that 99mTc-PAC-G may potentially be used in breast tissue as an imaging agent.

Rapid-Onset Acute Respiratory Distress Syndrome (ARDS) in a Patient Undergoing Metastatic Liver Resection: A Case Report and Review of the Literature

Metastatic liver resection following cytoreductive chemotherapy is an accepted treatment for oligometastatic tumor diseases. Although pulmonary complications are frequently reported in patients undergoing liver surgery including liver transplantation, life-threatening acute respiratory failures in the absence of aspiration, embolism, transfusion-related acute lung injury (TRALI), pulmonary infection, or an obvious source of systemic sepsis are rare. We performed an extensive clinical review of a patient undergoing metastatic liver resection who had a clinical course compatible to an acute respiratory distress syndrome (ARDS) without an obvious cause except for the surgical procedure and multiple preoperative chemotherapies. We hypothesize that either the surgical procedure mediated by cytokines and tumor necrosis factor or possible toxic effects of oxygen applied during general anesthesia were associated with life-threatening respiratory failure in the patient. Discrete and subclinical inflammated alveoli (probably due to multiple preoperative chemotherapies with substances at potential risk for interstitial pneumonitis as well as chest radiation) might therefore be considered as risk factors.