Chemotherapy for advanced gastric or gastroesophageal cancer: defining the contributions of docetaxel

CD-PLLD co-delivering docetaxel and MMP-9 siRNA plasmid for nasopharyngeal carcinoma therapy in vivo

The co-delivery of a drug and a target gene has become a primary strategy in cancer therapy. Based on our previous study, a synthesized star‑shaped co‑polymer consisting of β‑cyclodextrin (CD) and a poly(L‑lysine) dendron (PLLD) was used to co-deliver docetaxel (DOC) and matrix metalloproteinase 9 (MMP‑9) small interfering RNA, via CD‑PLLD/DOC/MMP‑9 complexes, into mice implanted with HNE‑1 human nasopharyngeal carcinoma (NPC) tumor cells in vivo. Unlike the commonly used amphiphilic co‑polymer micelles, the obtained CD derivative may be used directly for a combined delivery of nucleic acid and hydrophobic DOC without a complicated micellization process. In vivo assays demonstrated that CD‑PLLD/DOC/MMP‑9 inhibited HNE‑1 tumor growth and decreased proliferating cell nuclear antigen expression levels, indicating a potential strategy for NPC therapy. In addition, the distribution of DOC and MMP‑9 was investigated; CD‑PLLD/DOC/MMP‑9 complexes were phagocytized in reticuloendothelial systems, including the liver and spleen, which requires further study. Furthermore, the complexes did not cross the blood‑brain barrier due to their large molecular size, suggesting they may be relatively safe. Additionally, the complexes mediated increased DOC concentrations with prolonged blood circulation and EGFP expression in HNE‑1 tumors. These results suggest the future potential application of CD-PLLD/DOC/MMP-9 for NPC therapy.

Advanced gastric adenocarcinoma: optimizing therapy options

INTRODUCTION

Gastric adenocarcinoma (GAC) is the fifth most common cancer and third leading cause of cancer related mortality worldwide. When localized, cure is achievable with surgery and adjunctive therapies in some patients, however, once advanced, GAC is not a curable condition. Only two targeted agents (trastuzumab and ramucirumab) have been approved and apatinib was approved only in China. Because of the heterogeneous nature of GAC, it is not possible to assess a standard therapeutic approach. Areas covered: In this review, we aimed to describe the optimal systemic therapy regimens for advanced GAC. A literature search was performed to identify all phase II-III studies about advanced GAC from PubMed, clinicaltrials.gov, American Society of Clinical Oncology (ASCO) and European Society for Medical Oncology (ESMO) websites. Expert commentary: A combination of a platinum compound and a fluoropyrimidine is ideal as first line therapy. Trastuzumab should be added if the tumor is HER2 positive. In the second line setting, paclitaxel/ramucirumab is preferred over ramucirumab alone. Recently, two similar molecular classifications for GAC have been proposed. A better understanding of molecular and immune biology of GAC could identify new therapeutic targets.

Open-label, randomized, single-dose, crossover study to evaluate the pharmacokinetics and safety differences between two docetaxel products, CKD-810 and Taxotere injection, in patients with advanced solid cancer

PURPOSE

The aim of this study was to compare CKD-810 (test docetaxel) with Taxotere(®) (reference docetaxel) in terms of pharmacokinetics and safety for patients with advanced or metastatic carcinoma.

METHODS

A randomized, open-label, two-way crossover study was conducted in eligible patients. Patients received with reference or test drugs of 75 mg/m(2) docetaxel by intravenous infusion for 60 min in the first period and the alternative drug in the second period with a washout of 3 weeks. Plasma concentrations of docetaxel were determined by validated high-performance liquid chromatography coupled to tandem mass spectrometry detection. Pharmacokinetic parameters, including the maximum plasma concentration (C(max)) and the area under the concentration-time curve (AUC), were determined by non-compartmental analysis.

RESULTS

A total of 44 patients were included in the study, 21 patients received test drug and 23 received reference drug for the first cycle. The C(max) of docetaxel was 2,658.77 ng/mL for test drug and 2,827.60 ng/mL for reference drug, and two drugs showed no difference with a statistical significance. Time to reach C(max) (T(max)) of CKD-810 (0.94 h) versus reference docetaxel (0.97 h) was also not significantly different. Other pharmacokinetic parameters including the plasma AUC, elimination half-life, and total body clearance exhibited similar values without a significant difference. The most common grade 3 or 4 toxicity was neutropenia (CKD-810 19.5 or 29.3 %; reference docetaxel 14.6 or 41.5 %). Febrile neutropenia was experienced by only one patient in each group. Two patients died of progression of disease during the study.

CONCLUSION

Docetaxel anhydrous CKD-810 use with patients suffering advanced or metastatic solid malignancies was equivalent to reference docetaxel in terms of pharmacokinetic parameters and safety profile. Additionally, the test and reference drug met the regulatory criteria for pharmacokinetic equivalence.

The role of taxanes in the management of gastroesphageal cancer

Upper gastrointestinal cancers commonly referred to as gastroesophageal carcinomas encompass cancers of the esophagus, stomach and gastroesophageal junction. Although the number of newly diagnosed cases of gastric cancer has decreased in the United States, the whole burden of upper gastrointestinal carcinomas on society remains significantly high, with only a small improvement in overall survival achieved over the past two decades. Traditionally, therapeutic agents used to treat gastroesophageal cancers have been platinums and fluoropyrimidines. Taxanes are di-terpenes produced by the plants of the genus Taxus (yews). As their name suggests, taxanes were first derived from natural sources, but now they are all synthesized artificially. Interfering with cellular microtubular function during cell division is the main mechanism of action for currently available taxanes. Since their introduction into therapeutic oncology, many different other taxane-derivatives have been manufactured and are being developed. Changing the formulation of the drug to improve delivery such as liposomal encapsulation, and target deliver with antibody-drug conjugation, as well as introducing new class of cytotoxic agents that can overcome taxane-resistance. The two most commonly used taxanes are paclitaxel and docetaxel. Taxane is a class of cytotoxic agents more commonly administered in patients with breast and lung cancers. However, the regulatory approval of docetaxel to treat patients with metastatic or advanced gastroesophageal cancers in 2006 established the role of taxanes in the management of upper gastroesophageal cancers. This paper will review the current data of taxanes in the management of patients with upper gastrointestinal cancers.

Pharmacokinetics, efficacy, and safety evaluation of docetaxel/hydroxypropyl-sulfobutyl-β-cyclodextrin inclusion complex

Hydroxypropyl-sulfobutyl-β-cyclodextrin (HP-SBE-β-CD) inclusion complex was developed and used as a drug delivery system for DTX (DTX/HP-SBE-β-CD). The objective of the present study was to evaluate and compare the biological properties of DTX/HP-SBE-Β-CD with Taxotere®. The pharmacokinetics, biodistribution, antitumor efficacy in vivo and in vitro, and safety evaluation of DTX/HP-SBE-β-CD were studied. The most significant finding was that it was possible to prepare a Polysorbate-80-free inclusion complex for DTX. Studies based on pharmacokinetics, biodistribution, and antitumor efficacy indicated that DTX/HP-SBE-β-CD had similar pharmacokinetic properties and antitumor efficacy both in vitro and in vivo as Taxotere®. Fortunately, this new drug delivery system attenuated the side effects when used in vivo. As a consequence, DTX/HP-SBE-β-CD may be a promising alternative to Taxotere® for cancer chemotherapy treatment with reduced side effects. The therapeutic potential against a variety of human tumors and low toxicity demonstrated in a stringent study clearly warrant clinical investigation of DTX/HP-SBE-β-CD for possible use against human tumors.

New insights into the mechanisms of gastric cancer multidrug resistance and future perspectives

Gastric cancer is still the second leading cause of cancer death worldwide. Chemotherapy is one of the major treatment options for advanced gastric cancer. The efficacy of chemotherapy for gastric cancer is poor due to insensitivity and the development of multidrug resistance (MDR). Gastric cancer MDR involves a large number of molecules and complex mechanisms. Classical drug-resistant molecules, such as P-glycoprotein/ABCB1 and MRP1/ABCC1, have been found to play important roles in mediating MDR in some gastric cancers. In recent years, new molecules and mechanisms have been found to be associated with the development of gastric cancer MDR and might provide new targets for tackling gastric cancer MDR. Combined use of molecularly targeted therapy with chemotherapy may offer improved outcomes for gastric cancer patients and might provide new threads of hope for gastric cancer treatment.

In vivo anti-tumor efficacy of docetaxel-loaded thermally responsive nanohydrogel

Thermally responsive poly(N-isopropylacrylamide-co-acrylamide) (P(NIPA-co-AAm)) nanohydrogel (NHG) with a diameter of about 50 nm and a lower critical solution temperature (LCST) of about 40 degrees C was synthesized by a previously reported precipitation polymerization method. The physical properties including LCST, diameter and morphology were characterized. Four hydrophobic model drugs (5-fluorouracil (5-FU), fluorescein, docetaxel (DTX) and near-infrared dye-12 (NIRD-12)) with different hydrophilicities were respectively entrapped into the nanoparticles and their in vitro release kinetics from NHG was investigated. DTX was ultimately chosen as the goal anti-tumor drug and optimally entrapped into NHG with a drug loading content (DLC) of 7.38% and encapsulation efficiency (EE) of 73.8%. An in vitro drug release test indicated that DTX-loaded NHG had zero-order release kinetics at 43 degrees C. The respective anti-tumor efficacy of DTX-loaded NHG with or without hyperthermia on tumor tissue was evaluated in Kunming mice-bearing S180 sarcoma. The inhibition rates of DTX-loaded NHG with or without hyperthermia were 78.15% and 48.78%, respectively. DTX-loaded NHG also showed much lower toxicity during the therapeutic procedure. Results indicated that this kind of thermally responsive, drug-loaded NHG could be used as a promising strategy for tumor therapy with the help of local hyperthermia treatment.

Feasibility of self-expandable metallic stent plus chemotherapy for metastatic gastric cancer with pyloric stenosis

BACKGROUND AND AIM

Self-expandable metallic stent placement is accepted as palliative therapy for advanced gastric cancer with gastric outlet obstruction, but data are lacking for chemotherapy after self-expandable metallic stent insertion. This study retrospectively compared results between surgery plus chemotherapy and stenting plus chemotherapy for metastatic gastric cancer with pyloric stenosis.

METHODS

Subjects comprised 26 patients who received chemotherapy after surgery or endoscopic stenting for metastatic gastric cancer with pyloric stenosis between April 2000 and December 2007 in four Japanese hospitals. Patients were categorized into two groups: 15 patients who received chemotherapy after surgery for pyloric stenosis (Surgery group); and 11 patients who received chemotherapy after self-expandable metallic stent placement for pyloric stenosis (Stent group).

RESULTS

Median survival time and median time to treatment failure were 284 days and 226 days in the Surgery group and 337 days and 247 days in the Stent group, respectively. No significant differences were noted between survival and time to treatment failure. No significant differences were found in median oral intake rate (Surgery, 93.1%; Stent, 93.2%) or median hospital stay rate (Surgery, 24.6%; Stent, 23.7%) during survival. Response rate was 45.5% in the Surgery group and 50% in the Stent group, with no significant difference. Likewise, no significant differences were noted between groups for frequencies of toxicity or complications.

CONCLUSIONS

The present results suggest that chemotherapy after stenting is as effective and safe as chemotherapy after surgery. Stents may replace surgery in combination therapy with chemotherapy for metastatic gastric cancer with gastric outlet obstruction.

The antitumor effect of novel docetaxel-loaded thermosensitive micelles

To further evaluate the novel docetaxel-loaded micelle based on the biodegradable thermosensitive copolymer poly(N-isopropylacrylamide-co-acrylamide)-b-poly(dl-lactide) that we had synthesized before, in this paper, we studied its in vitro cytotoxicity in three different tumor cell lines by standard MTT assays using different tumor cell lines, followed by studies of acute toxicity and the tumor distribution studies which were conducted in Kunming mice. Meanwhile, the in vivo antitumor efficacy as well as toxicity of the micelle was evaluated in C57BL/6 mice. According to our findings, the in vitro cytotoxicity of docetaxel-loaded micelles was lower than that of the conventional docetaxel formulation at 37 degrees C, while hyperthermia greatly enhanced the efficacy of drug-loaded micelles. The acute toxicity study showed reduced toxicity of docetaxel-loaded micelle compared to that of conventional docetaxel formulation. Moreover, docetaxel-loaded micelle enabled a prominent higher docetaxel concentration in tumor than conventional docetaxel formulation. Furthermore, a significantly higher antitumor efficacy was observed in mice treated with docetaxel-loaded micelles accompanied by hyperthermia; docetaxel-loaded micelles also caused less body weight loss of mice. This study demonstrates an increased antitumor efficacy and reduced toxicity of the novel docetaxel-loaded micelle and indicates its prospect of clinical applications.

Targeting therapy with docetaxel thermosensitive nano-micelles of human gastric cancer xenografts in nude mice

AIM: To study the curative effects of docetaxel thermosensitive nano-micelles on human gastric cancer xenografts in nude mice.

METHODS: Human gastric cancer cell line BGC-823 was implanted into 48 nude mice. Different drugs were injected through the caudal vein in eight groups after establishment of the experimental model. Permanent temperature of the tumor was taken in the thermotherapy group. Tumor growth was monitored once every other day. Dynamic viewing and determining the rate of tumor regression in terms of tumor weight and volume were used to evaluate therapeutic efficacy. The side effect was evaluated through surveying all the condition and the relative variation in mouse body weight.

RESULTS: Tumor growth speed in the docetaxel thermosensitive nano-micelle thermotherapy group was significantly slower than that in the other groups. Tumor volume and weight regression in the docetaxel thermosensitive nano-micelle thermotherapy group were 81.5% and 85.4%, respectively, which were markedly higher than those of the docetaxel thermosensitive nano-micelle group (32.2% and 37.5%) and the docetaxel injection group (49.2% and 58.0%) (both P < 0.05). The drug side effects and toxicity of docetaxel thermosensitive nano-micelle thermotherapy were significantly less than those in the other groups.

CONCLUSION: Docetaxel thermosensitive nano-micelles show good inhibition of tumor growth, which indicates a favorable potential in clinical application.

Multidrug resistance in gastric cancer: recent research advances and ongoing therapeutic challenges

Gastric cancer is the second leading cause of cancer mortality worldwide. The major cause of treatment failure for gastric cancer is the development of multidrug resistance (MDR) to chemotherapy, which is currently one of the primary treatment options. Recently, research into the MDR of gastric cancer has revealed that, in addition to the classical ATP-binding cassette transporters, such as P-glycoprotein (P-gp) and MDR-associated protein (MRP)1, a number of other molecules might mediate the drug resistance of human gastric cancer. The absence of P-gp and MRP1 expression in some gastric cancer cases also indicates that there might be other mechanisms responsible for human gastric cancer MDR. These molecules belong to different functional families and might work together to confer MDR phenotypes. The new findings may provide new clues to the mechanisms of MDR and enable the selection of new candidates for targeting MDR in human gastric cancer.