Docetaxel in non-small cell lung cancer: a review

Conformation and energy investigation of microtubule longitudinal dynamic instability induced by natural products

The natural products plinabulin, docetaxel, and vinblastine are microtubule targeting agents (MTAs). They have been used alone or in combination in cancer treatment. However, the exact nature of their effects on microtubule (MT) polymerization dynamics is poorly understood. To elucidate the longitudinal conformational and energetic changes during MT dynamics, a total of 140 ns molecular dynamic simulations combined with binding free energy calculations were performed on seven tubulin models. The results indicated that the drugs disrupted MT polymerization by altering both MT conformation and binding free energy of the neighboring tubulin subunits. The combination of plinabulin and docetaxel destabilized MT polymerization due to bending MT and weakening the polarity of tubulin polymerization. The new combination of docetaxel and vinblastine synergistically enhanced MT depolymerization and bending, while plinabulin and vinblastine had no synergistic inhibitory effects. The results were verified by the tubulin assembly assay. Our study obtained a comprehensive understanding of the action mechanisms of three natural drugs and their combinations on MT dynamic, provided theoretical guidance for new MTA combinations, and would promote the optimal use of MTA and contribute to developing new MTAs as anticancer agents.

Polyphyllin II induced apoptosis of NSCLC cells by inhibiting autophagy through the mTOR pathway

CONTEXT

Polyphyllin II (PPII) is a steroidal saponin isolated from Rhizoma Paridis. It exhibits significant antitumor activity such as anti-proliferation and pro-apoptosis in lung cancer.

OBJECTIVE

To explore whether PPII induce autophagy and the relationship between autophagy and apoptosis in non-small cell lung cancer (NSCLC) cells.

MATERIALS AND METHODS

The effects of PPII (0, 1, 5, and 10 μM) were elucidated by CCK8 assay, colony formation test, TUNEL staining, MDC method, and mRFP-GFP-LC3 lentivirus transfection in A549 and H1299 cells for 24 h. DMSO-treated cells were selected as control. The protein expression of autophagy (LC3-II, p62), apoptosis (Bcl-2, Bax, caspase-3) and p-mTOR was detected by Western blotting. We explored the relationship between autophagy and apoptosis by autophagy inhibitor CQ (10 μM) and 3-MA (5 mM).

RESULTS

PPII (0, 1, 5, and 10 μM) inhibited the proliferation and induced apoptosis. The IC₅₀ values of A549 and H1299 cells were 8.26 ± 0.03 and 2.86 ± 0.83 μM. We found that PPII could induce autophagy. PPII promoted the formation of autophagosome, increased the expression of LC3-II/LC3-I (p < 0.05), while decreased p62 and p-mTOR (p < 0.05). Additionally, the co-treatment with autophagy inhibitors promoted the protein expression of c-caspase-3 and rate of Bax/Bcl-2 (p < 0.05), compared with PPII-only treatment group. Therefore, our results indicated that PPII-induced autophagy may be a mechanism to promote cell survival, although it can also induce apoptosis.

CONCLUSIONS

PPII-induced apoptosis exerts its anticancer activity by inhibiting autophagy, which will hopefully provide a prospective compound for NSCLC treatment.

Chemosensitization Effect of Seabuckthorn (Hippophae rhamnoides L.) Pulp Oil via Autophagy and Senescence in NSCLC Cells

The research has demonstrated a synergistic anticancer effect of Seabuckthorn pulp oil (SBO) and the standard chemotherapy regimen Docetaxel (DTX) against two non-small cell lung cancer (NSCLC) cell lines: A549 and H23. The synergizing effect of an SBO and DTX combination was detected utilizing SRB assay and combination index (CI) approaches. Flow cytometry was carried out using fluorescent probes to measure cell cycle analysis by DNA content and reactive oxygen species (ROS) generation. Further, we demonstrated that the synergistic anticancer activity of SBO merged with DTX was achieved by caspase-independent autophagy and senescence induction. These changes were concomitant with increased generation of ROS production and microtubule-associated protein 1 light chain 3 (LC3) protein expression, G1-phase arrest, and enhanced senescence-associated β-galactosidase staining activity. Our data also demonstrated that SBO or DTX treatment groups solely upregulated the phosphorylation of ERK, which coincided with the induction of autophagy vacuoles and was functionally associated with ROS activation. Moreover, endogenous LC3 puncta staining was performed and monitored by confocal microscopy. Overall, these results suggest new mechanisms for the antitumor activity of SBO co-treated with DTX through triggering autophagic cell death and senescence against cancer cells as a result of sustained ERK phosphorylation and intracellular ROS production in NSCLC. In addition, we also highlight SBO as an alternative therapeutic option or adjunct therapeutic strategy in combination with chemotherapeutic agents in lung cancer therapy management.

An effective strategy for development of docetaxel encapsulated gold nanoformulations for treatment of prostate cancer

Nanoformulation based drug delivery is one of the most important research areas in the field of nanomedicine, which provides promising alternatives to the limitations of conventional chemotherapy. Nano drug delivery enables improved pharmacokinetic profile, bioavailability and therapeutic efficiency compared to the regular chemotherapeutic drugs. Herein, we have established a simple method for the synthesis of docetaxel (Dtx) encapsulated poly (ethylene glycol) (PEG) functionalized gold nanoparticles (AuNPs) for targeted drug delivery to prostate cancer. AuNPs were synthesized by the citrate ion reduction method followed by functionalization with thiol-PEG-amine (SH-PEG-NH2). SH-PEG-NH2 functionalized AuNPs were conjugated with the targeting vehicle, folic acid (FA). The anticancer drug, Dtx was encapsulated within AuNPs by the non-covalent linkage method. The physicochemical characteristics of the synthesized nanoformulations were extensively characterized by various spectral and microscopic studies. HR-TEM indicates the average size of the AuNPs is 16 nm and the nanoformulations is 18 nm. The encapsulation efficiency of the Dtx is ~ 96% which is confirmed by the elemental mapping analysis. The in vitro drug release profile of Dtx and AuNPs nanoformulations were studied by the dialysis membrane method. The anticancer activity of docetaxel encapsulated AuNPs were evaluated with prostate cancer cell lines (PC3). The drug encapsulated nanoformulations reduced the cell viability to about 40% (40 µM concentration at 24, 48 and 72 h of treatment). The optical microscopy observation reveals that the damage of prostate cancer cells after exposure to Dtx encapsulated AuNPs. The good cytotoxic activity of the present nanoformulation against prostate cancer cell lines enables its application for targeted drug delivery to prostate cancer.

Anticancer Effects of Antihypertensive L-Type Calcium Channel Blockers on Chemoresistant Lung Cancer Cells via Autophagy and Apoptosis

Purpose

Hypertension and cancer are frequently found comorbidity occurring in same individual. This study was intended to evaluate the anticancer effects of commonly used antihypertensive medications and chemotherapy on chemoresistant lung cancer cells.

Methods

Calcium channel blockers (CCBs), including Verapamil, Diltiazem, and Nifedipine, either alone or combined with docetaxel (DOC) or vincristine (VCR) were used to treat A549 lung adenocarcinoma chemoresistant sublines. Cell viability was determined by MTT assay, and colony formation assay was used to demonstrate the long-term effect of CCBs on proliferation of the sublines. Apoptosis was evaluated by Annexin V assay and autophagy intensity was quantitated from acidic vesicular organelle formation. Pan-caspase inhibitor, shATG5 interference and chloroquine were applied to study the roles of Verapamil on apoptosis and autophagy, with related proteins verified by Western blot analysis.

Results

Results show that 10 μM of Verapamil and Diltiazem, but not Nifedipine, differentially induce autophagy in DOC-resistant or VCR-resistant A549 cells, respectively. When CCBs are combined with DOC or VCR to treat the sublines, 10 μM of Verapamil induces autophagy more significantly than Diltiazem and Nifedipine, respectively, in DOC-resistant (54.91±0.76, 18.03±0.69, 7.05±0.30) or VCR-resistant A549 (32.41±1.04, 21.51±0.63, 7.14±0.24) cells. Inhibition of apoptosis by pan-caspase inhibitor partly reduced cell death indicates association of caspase-dependent cell death but with persistence of autophagy. Inhibition of autophagy by interfering ATG5 expression reduced c-PARP level and apoptotic cells suggest a pro-death role of autophagy. Chloroquine treatment enhanced autophagosome accumulation and cell death but with reduced c-PARP level suggests that mechanism of caspase-independent cell death also contributes to Verapamil/chemotherapy-induced anticancer effects. 

Conclusion

Verapamil combined with DOC or VCR induces chemoresistant lung cancer cells to death through autophagy burst and apoptosis more strongly than Diltiazem and Nifedipine. Administering Verapamil or Diltiazem individually with chemotherapy, but not Nifedipine, can be considered in lung cancer patients with hypertension.

Protein Corona over Mesoporous Silica Nanoparticles: Influence of the Pore Diameter on Competitive Adsorption and Application to Prostate Cancer Diagnostics

Diagnostic tests based on proteomics analysis can have significant advantages over more traditional biochemical tests. However, low molecular weight (MW) protein biomarkers are difficult to identify by standard mass spectrometric analysis, as they are usually present at low concentrations and are masked by more abundant resident proteins. We have previously shown that mesoporous silica nanoparticles are able to capture a predominantly low MW protein fraction from the serum, as compared to the protein corona (PC) adsorbed onto dense silica nanoparticles. In this study, we begin by further investigating this effect using liquid chromatography-mass spectrometry (LC-MS)/MS and thermogravimetric analysis (TGA) to compare the MW of the proteins in the coronas of mesoporous silica nanoparticles with the same particle size but different pore diameters. Next, we examine the process by which two proteins, one small and one large, adsorb onto these mesoporous silica nanoparticles to establish a theory of why the corona becomes enriched in low MW proteins. Finally, we use this information to develop a novel system for the diagnosis of prostate cancer. An elastic net statistical model was applied to LC-MS/MS protein coronas from the serum of 22 cancer patients, identifying proteins specific to each patient group. These studies help to explain why low MW proteins predominate in the coronas of mesoporous silica nanoparticles, and they illustrate the ability of this information to supplement more traditional diagnostic tests.

DKK4-knockdown enhances chemosensitivity of A549/DTX cells to docetaxel

Drug resistance greatly limits docetaxel efficiency in the treatment of non-small cell lung cancer (NSCLC). Dickkopf 4 (DKK4), a negative regulator of Wnt/β-catenin pathway, is believed to be involved in various human cancers; whereas the association of DKK4 with acquired docetaxel resistance in NSCLC remains unclear. In the present study, we investigated the involvement of DKK4 in the docetaxel-resistant human lung adenocarcinoma A549 (A549/DTX) cells. Our results showed that DKK4 expression was significantly increased in the A549/DTX cells compared with in the A549 cells, as well as in the culture supernatant of A549/DTX cells. DKK4 overexpression increased the resistance of A549 cells to docetaxel. DKK4-knockdown promoted inhibition of A549/DTX cell growth, and reduced the colony formation and invasion capacity of A549/DTX cells. Moreover, DKK4-knockdown promoted the pro-apoptotic effect of docetaxel characterized with caspase 3 activation and inhibition of BCL-2 expression in A549/DTX cells, which was possibly mediated by inducing the activation of c-Jun N-terminal kinase (JNK)-related signaling pathway. Thus, our results indicated that DKK4-knockdown promoted the cytotoxic and pro-apoptotic activity of A549/DTX cells, which suggests a critical role of DKK4 in docetaxel resistance of the A549 cells and provides the potential to combine docetaxel therapy with DKK4 depletion in treating NSCLC.

Polyphyllin G induce apoptosis and autophagy in human nasopharyngeal cancer cells by modulation of AKT and mitogen-activated protein kinase pathways in vitro and in vivo

Polyphyllin G (also call polyphyllin VII), extract from rhizomes of Paris yunnanensis Franch, has been demonstrated to have strong anticancer activities in a wide variety of human cancer cell lines. Previous studies found that Polyphyllin G induced apoptotic cell death in human hepatoblastoma cancer and lung cancer cells. However, the underlying mechanisms of autophagy in human nasopharyngeal carcinoma (NPC) remain unclear. In this study, Polyphyllin G can potently induced apoptosis dependent on the activations of caspase-8, -3, and -9 and the changes of Bcl-2, Bcl-xL and Bax protein expression in different human NPC cell lines (HONE-1 and NPC-039). The amount of both LC3-II and Beclin-1 was intriguingly increased suggest that autophagy was induced in Polyphyllin G-treated NPC cells. To further clarify whether Polyphyllin G-induced apoptosis and autophagy depended on AKT/ERK/JNK/p38 MAPK signaling pathways, cells were combined treated with AKT inhibitor (LY294002), ERK1/2 inhibitor (U0126), p38 MAPK inhibitor (SB203580), or JNK inhibitor (SP600125). These results demonstrated that Polyphyllin G induced apoptosis in NPC cells through activation of ERK, while AKT, p38 MAPK and JNK were responsible for Polyphyllin G-induced autophagy. Finally, an administration of Polyphyllin G effectively suppressed the tumor growth in the NPC carcinoma xenograft model in vivo. In conclusion, our results reveal that Polyphyllin G inhibits cell viability and induces apoptosis and autophagy in NPC cancer cells, suggesting that Polyphyllin G is an attractive candidate for tumor therapies. Polyphyllin G may promise candidate for development of antitumor drugs targeting nasopharyngeal carcinoma.

Development of combretastatins as potent tubulin polymerization inhibitors

The combretastatins are isolated from South African tree combretum caffrum kuntze. The lead compound combretastatin A-4 has displayed remarkable cytotoxic effect in a wide variety of preclinical tumor models and inhibits tubulin polymerization by interacting at colchicine binding site of microtubule. However, the structural simplicity of C A-4 is favorable for synthesis of various derivatives projected to induce rapid and selective vascular shutdown in tumors. Majority of the molecules have shown excellent antiproliferative activity and are able to inhibit tubulin polymerization as well as possible mechanisms of action have been investigated. In this review article, the synthesis and structure-activity relationships of C A-4 and immense number of its synthetic derivatives with various modifications on the A, B-rings, bridge carbons and their anti mitotic activities are discussed.

Polyphyllin G induces apoptosis and autophagy cell death in human oral cancer cells

BACKGROUND

Polyphyllin G (also called polyphyllin VII), extract from rhizomes of Paris yunnanensis Franch, has been shown to have strong anticancer activities in a wide variety of human cancer cell lines. However, the underlying influences of autophagy in human oral squamous cell carcinoma (OSCC) remain unclear.

METHODS

In this study, the roles of apoptosis and autophagy in polyphyllin G-induced death in human oral cancer cells were investigated. Moreover, the molecular mechanism of the anticancer effects of polyphyllin G in human oral cancer cells was investigated.

RESULTS

The results revealed that polyphyllin G significantly inhibited cell proliferation in human oral cancer cells; it dose-dependently induced apoptosis in SAS and OECM-1 cells through caspase-3, -8, and -9 activation and poly (ADP-ribose) polymerase cleavage. In addition, changes were observed in Bcl-2 and proapoptosis-related protein expression in different human oral cancer cell lines. The expression of both LC3-II and beclin-1 was markedly increased, suggesting the induction of autophagy in polyphyllin G-treated oral cells. To further clarify whether polyphyllin G-induced apoptosis and autophagy depended on Akt/extracellular signal-regulated kinases (ERK)/c-Jun N-terminal kinases (JNK)/p38 mitogen-activated protein kinases (MAPK) signaling pathways, the cells were cotreated with inhibitors. The results demonstrated polyphyllin G-induced apoptosis in oral cells through the activation of ERK, Akt, p38 MAPK, and JNK, whereas ERK and JNK accounted for polyphyllin G-induced autophagy.

CONCLUSION

This study is the first to demonstrate apoptosis and autophagy during polyphyllin G-induced cell death in human oral cancer cell lines. These results suggest that polyphyllin G is a promising candidate for developing antitumor drugs targeting human oral squamous cell carcinoma.

FoxM1 inhibition enhances chemosensitivity of docetaxel-resistant A549 cells to docetaxel via activation of JNK/mitochondrial pathway

Docetaxel is recommended as a second-line chemotherapy agent for the non-small-cell lung cancer (NSCLC); however, drug resistance greatly limits its efficiency. Forkhead box M1 (FoxM1), an oncogenic transcription factor, is believed to be involved in the chemoresistance of various human cancers; whereas the association of FoxM1 with acquired docetaxel-resistance in NSCLC remains unclear. In the present study, we investigated the involvement of FoxM1 in the docetaxel-resistant human lung adenocarcinoma A549 cells (A549/DTX). Our results showed that FoxM1 expression was significantly increased in the A549/DTX cells compared with that in the parental A549 cells. FoxM1 siRNA silencing promoted the cytotoxic and pro-apoptotic effect of docetaxel in A549/DTX cells, which was possibly mediated through inducing the activation of c-Jun N-terminal kinases/mitochondrial signaling pathway. Our results suggest a critical role of FoxM1 in docetaxel-resistance of the A549 cells and form the basis for the development of combined therapy of docetaxel and FoxM1 depletion in treating NSCLC.

Dehydroandrographolide, an iNOS inhibitor, extracted from Andrographis paniculata (Burm.f.) Nees, induces autophagy in human oral cancer cells

Autophagy, which is constitutively executed at the basal level in all cells, promotes cellular homeostasis by regulating the turnover of organelles and proteins. Andrographolide and dehydroandrographolide (DA) are the two principle components of Andrographis paniculata (Burm.f.) Nees. and are the main contributors to its therapeutic properties. However, the pharmacological activities of dehydroandrographolide (DA) remain unclear. In this study, DA induces oral cancer cell death by activating autophagy. Treatment with autophagy inhibitors inhibited DA-induced human oral cancer cell death. In addition, DA increased LC3-II expression and reduced p53 expression in a time- and concentration-dependent manner. Furthermore, DA induced autophagy and decreased cell viability through modulation of p53 expression. DA-induced autophagy was triggered by an activation of JNK1/2 and an inhibition of Akt and p38. In conclusion, this study demonstrated that DA induced autophagy in human oral cancer cells by modulating p53 expression, activating JNK1/2, and inhibiting Akt and p38. Finally, an administration of DA effectively suppressed the tumor formation in the oral carcinoma xenograft model in vivo. This is the first study to reveal the novel function of DA in activating autophagy, suggesting that DA could serve as a new and potential chemopreventive agent for treating human oral cancer.

Fibronectin protects lung cancer cells against docetaxel-induced apoptosis by promoting Src and caspase-8 phosphorylation

Fibronectin is involved in orchestrating many diverse cellular behaviors, including adhesion, invasion, differentiation, and proliferation and recently has also been shown to participate in the development of chemoresistance. In this study, we found that fibronectin expression was inversely correlated with clinical responses to docetaxel treatment in non-small cell lung cancer patients. Subsequently, we showed that fibronectin pretreatment could enhance cell viability and reduce apoptosis in docetaxel-treated lung cancer cells because fibronectin induced phosphorylated Src and caspase-8, rendering the later inactive, thus inhibiting docetaxel-induced apoptosis. The inhibition of apoptosis by fibronectin was found to be enhanced by Src overexpression and reversed by Src knockdown in lung cancer cells. Further investigation revealed that a downregulation of phospho-Src via treatment with a Src kinase inhibitor could also abolish fibronectin activity and recover docetaxel-induced apoptosis. Molecular studies revealed that this reversion was due to decreased phospho-Src levels rather than a reduction in total Src expression. Inhibition of phospho-Src reduced phospho-caspase-8 and promoted caspase-8 activity, restoring apoptosis following docetaxel and fibronectin co-treatment. Finally, xenografts experiments demonstrated that fibronectin promoted lung cancer cell proliferation during docetaxel treatment in vivo. Our findings indicate that fibronectin promotes Src and caspase-8 phosphorylation in lung cancer cells, which decreases caspase-8 activation and protects tumor cells from docetaxel-induced apoptosis. Therefore, the fibronectin/Src/caspase-8 pathway may play a crucial role in docetaxel resistance in lung cancer.

Immunomodulatory Protein from Ganoderma microsporum Induces Pro-Death Autophagy through Akt-mTOR-p70S6K Pathway Inhibition in Multidrug Resistant Lung Cancer Cells

Chemoresistance in cancer therapy is an unfavorable prognostic factor in non-small cell lung cancer (NSCLC). Elevation of intracellular calcium level in multidrug resistant (MDR) sublines leads to sensitization of MDR sublines to cell death. We demonstrated that a fungal protein from Ganoderma microsporum, GMI, elevates the intracellular calcium level and reduces the growth of MDR subline via autophagy and apoptosis, regardless of p-glycoprotein (P-gp) overexpression, in mice xenograft tumors. In addition, we examined the roles of autophagy in the death of MDR A549 lung cancer sublines by GMI, thapsigargin (TG) and tunicamycin (TM) in vitro. Cytotoxicity of TG was inhibited by overexpressed P-gp. However, TM-induced death of MDR sublines was independent of P-gp level. Combinations of TG and TM with either docetaxel or vincristine showed no additional cytotoxic effects on MDR sublines. TG- and TM-mediated apoptosis of MDR sublines was demonstrated on Annexin-V assay and Western blot and repressed by pan-caspase inhibitor (Z-VAD-FMK). Treatment of MDR sublines with TG and TM also augmented autophagy with accumulation of LC3-II proteins, breakdown of p62 and formation of acidic vesicular organelles (AVOs). Inhibition of ATG5 by shRNA silencing significantly reduced autophagy and cell death but not apoptosis following TG or TM treatment. GMI treatment inhibited the phosphorylation of Akt/S473 and p70S6K/T389. Interestingly, the phosphorylation of ERK was not associated with GMI-induced autophagy. We conclude that autophagy plays a pro-death role in acquired MDR and upregulation of autophagy by GMI via Akt/mTOR inhibition provides a potential strategy for overcoming MDR in the treatment of lung cancers.

Pterostilbene induce autophagy on human oral cancer cells through modulation of Akt and mitogen-activated protein kinase pathway

OBJECTIVES

Extensive research supports the administration of herbal medicines or natural foods during cancer therapy. Pterostilbene, a naturally occurring phytoalexin, has various pharmacological activities, including antioxidant activity, cancer prevention activity, and cytotoxicity to many cancers. However, the effect of pterostilbene on the autophagy of tumor cells has not been clarified.

MATERIALS AND METHODS

In this study, the unique effects of pterostilbene on the autophagy of human oral cancer cells were investigated.

RESULTS

The results of this study showed that pterostilbene effectively inhibited the growth of human oral cancer cells by inducing cell cycle arrest and apoptosis. In addition, the formation of acidic vesicular organelles and LC3-II production also demonstrated that pterostilbene induced autophagy. Administering 3-methylamphetamine (3-MA) and bafilomycin A1 (BafA1) exerted differing effects on the pterostilbene-induced death of human oral cancer cells. Pterostilbene-induced autophagy was triggered by activation of JNK1/2 and inhibition of Akt, ERK1/2, and p38.

CONCLUSION

In conclusion, this study demonstrated that pterostilbene caused autophagy and apoptosis in human oral cancer cells, suggesting that pterostilbene could serve as a new and promising agent for treating human oral cancer.

A phase I clinical trial of dose escalation of lobaplatin in combination with fixed-dose docetaxel for the treatment of human solid tumours that had progressed following chemotherapy

In this study, the maximum tolerated dose (MTD) of lobaplatin (LBP) when it was combined with docetaxel (TXT) for the treatment of solid tumours that had progressed following chemotherapy was determined, and toxicities to this regimen were evaluated. A modified Fibonacci method was used for the dose escalation of LBP. The patients received TXT (at a fixed dose of 60 mg/m²) on day one (d1) and LBP (at an initial tested dose of 30 mg/m²) on day two (d2) of a treatment cycle that was repeated every 21 days. Each dose group consisted of at least three cases. In the absence of dose-limiting toxicity (DLT), we proceeded to the next dose group, with a dose increment of 5 mg/m² between groups, until DLT occurred. The dose immediately below the dose that produced DLT was regarded as the MTD. The 17 patients examined in this study completed a total of 58 cycles of chemotherapy, and a total of three dose-escalation groups (30 mg/m² LBP, 35 mg/m² LBP, and 40 mg/m² LBP) were established. The main adverse event that was observed was myelosuppression. DLT occurred in four patients, including three patients in the 40 mg/m² LBP group and one patient in the 35 mg/m² LBP group. In total, three out of the four patients in the 40 mg/m² LBP group exhibited DLT. We determined that the treatment administered to the 35 mg/m² LBP group represented the MTD. Thus, our phase I trial revealed that the MTD for the tested LBP combination regimen was 35 mg/m² LBP and 60 mg/m² TXT. This regimen resulted in mild adverse reactions and favourable patient tolerance. Therefore, we recommend the use of these dosages in phase II clinical trials.

Successful Treatment of Pulmonary Metastasis and Local Recurrence of Angiosarcoma with Docetaxel

Angiosarcoma of the face and scalp of the elderly frequently recurs locally, metastasizes early despite various treatments, and has a poor prognosis. We describe a patient who had angiosarcoma of the scalp with pulmonary metastasis. Local recurrence occurred after excision and local and arterial administration of IL-2. A weekly administration method of docetaxel was therefore selected, resulting in complete remission of the pulmonary metastasis and a partial response of the local recurrence. This favorable clinical outcome in our case suggests that docetaxel therapy may be an option for the treatment of angiosarcoma of the scalp with pulmonary metastasis.

Psoralen reverses docetaxel-induced multidrug resistance in A549/D16 human lung cancer cells lines

Chemotherapy is the recommended treatment for advanced-stage cancers. However, the emergence of multidrug resistance (MDR), the ability of cancer cells to become simultaneously resistant to different drugs, limits the efficacy of chemotherapy. Previous studies have shown that herbal medicine or natural food may be feasible for various cancers as potent chemopreventive drug. This study aims to explore the capablility of reversing the multidrug resistance of docetaxel (DOC)-resistant A549 cells (A549/D16) of psoralen and the underlying mechanisms. In this study, results showed that the cell viability of A549/D16 subline is decreased when treated with psoralen plus DOC, while psoralen has no effect on the cell proliferation on A549 and A549/D16 cells. Furthermore, mRNA and proteins levels of ABCB1 were decreased in the presence of psoralen, while decreased ABCB1 activity was also revealed by flow cytometry. Based on these results, we believe that psoralen may be feasible for reversing the multidrug resistance by inhibiting ABCB1 gene and protein expression. Such inhibition will lead to a decrease in ABCB1 activity and anti-cancer drug efflux, which eventually result in drug resistance reversal and therefore, sensitizing drug-resistant cells to death in combination with chemotherapeutic drugs.

[A meta-analysis of platinum plus docetaxel or vinorelbine in the first-line treatment of advanced non-small cell lung cancer]

背景与目的

以铂类为基础联合第三代药物的双药化疗方案是治疗晚期非小细胞肺癌（non-small cell lung cancer, NSCLC）的标准一线治疗方案。本研究采用meta分析的方法评价多西他赛联合铂类（docetaxel plus platinum, DP）方案对比长春瑞滨联合铂类（vinorelbine plus platinum, VP）方案治疗晚期NSCLC的疗效和安全性。

方法

计算机检索Pubmed、EMBASE、Cochrane Library、中国期刊全文数据库（CNKI）、中国生物医学文献数据库（CBM）、中文科技期刊全文数据（VIP）库及万方数据库关于DP方案与VP方案治疗晚期NSCLC的随机对照试验（randomized controlled trial, RCT）。根据Cochrane Handbook 5.1.0的质量评价标准，用Stata 12.0软件进行统计学分析。

结果

研究共纳入7项RCTs，包括晚期NSCLC患者2, 381例。DP方案的2年生存率（HR=0.887, 95%CI: 0.810-0.972, P=0.010）、有效率（RR=1.276, 95%CI: 1.107-1.450, P=0.001）和腹泻发生率（RR=3.134, 95%CI: 1.918-5.121, P < 0.001）较VP方案高；DP方案减少了贫血的发生率（RR=0.386, 95%CI: 0.311-0.478, P < 0.001）；DP方案与VP方案在1年生存率、白细胞减少、中性粒细胞减少、血小板减少、厌食、恶心、呕吐方面的差异无统计学意义。

结论

DP方案虽然增加了腹泻发生率，但却减少了贫血的发生率，同时提高了2年生存率和有效率。相比VP方案，DP方案可能更适合一线治疗晚期NSCLC。

Comparison of pemetrexed and docetaxel as salvage chemotherapy for the treatment for nonsmall-cell lung cancer after the failure of epidermal growth factor receptor-tyrosine kinase inhibitors

OBJECTIVE

To compare the therapeutic effects and adverse reactions of pemetrexed and docetaxel as salvage chemotherapy in patients with nonsmall-cell lung cancer (NSCLC) after the failure of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKI).

METHODS

In this randomized Phase 2 trial, patients with NSCLC who had previously failed EGFR-TKI therapy were randomized to receive intravenous pemetrexed (500 mg/m(2) for 21 days [one cycle]) or docetaxel (75 mg/m(2) for 21 days [one cycle]). Therapeutic effects were evaluated according to Response Evaluation Criteria in Solid Tumours standards and adverse effects were evaluated according to the US National Cancer Institute Common Terminology Criteria for Adverse Events.

RESULTS

There was no statistically significant difference in disease control rate, response rate, median survival and 1-year survival between treatment groups. Rates of nausea, myelosuppression, renal damage and hair loss were significantly higher in the docetaxel group than the pemetrexed group.

CONCLUSION

Pemetrexed is effective and well tolerated as salvage chemotherapy in patients with NSCLC after EGFR-TKI failure and may be a suitable therapeutic option in these patients.

Intravital FRET imaging of tumor cell viability and mitosis during chemotherapy

Taxanes, such as docetaxel, are microtubule-targeting chemotherapeutics that have been successfully used in the treatment of cancer. Based on data obtained from cell cultures, it is believed that taxanes induce tumor cell death by specifically perturbing mitotic progression. Here, we report on data that suggest that this generally accepted view may be too simplified. We describe a high-resolution intravital imaging method to simultaneously visualize mitotic progression and the onset of apoptosis. To directly compare in vitro and in vivo data, we have visualized the effect of docetaxel on mitotic progression in mouse and human colorectal tumor cell lines both in vitro and in isogenic tumors in mice. We show that docetaxel-induced apoptosis in vitro occurs via mitotic cell death, whereas the vast majority of tumor cells in their natural environment die independent of mitotic defects. This demonstrates that docetaxel exerts its anti-tumor effects in vivo through means other than mitotic perturbation. The differences between in vitro and in vivo mechanisms of action of chemotherapeutics may explain the limited response to many of the anti-mitotic agents that are currently validated in clinical trials. Our data illustrate the requirement and power of our intravital imaging technique to study and validate the mode of action of chemotherapeutic agents in vivo, which will be essential to understand and improve their clinical efficacy.

Highly potent mRNA based cancer vaccines represent an attractive platform for combination therapies supporting an improved therapeutic effect

Direct vaccination with mRNA encoding tumor antigens is a novel and promising approach in cancer immunotherapy. CureVac's mRNA vaccines contain free and protamine-complexed mRNA. Such two-component mRNA vaccines support both antigen expression and immune stimulation. These self-adjuvanting RNA vaccines, administered intradermally without any additional adjuvant, induce a comprehensive balanced immune response, comprising antigen specific CD4+ T cells, CD8+ T cells and B cells. The balanced immune response results in a strong anti-tumor effect and complete protection against antigen positive tumor cells. This tumor inhibition elicited by mRNA vaccines is a result of the concerted action of different players. After just two intradermal vaccinations, we observe multiple changes at the tumor site, including the up-regulation of many genes connected to T and natural killer cell activation, as well as genes responsible for improved infiltration of immune cells into the tumor via chemotaxis. The two-component mRNA vaccines induce a very fast and boostable immune response. Therefore, the vaccination schedules can be adjusted to suit the clinical situation. Moreover, by combining the mRNA vaccines with therapies in clinical use (chemotherapy or anti-CTLA-4 antibody therapy), an even more effective anti-tumor response can be elicited. The first clinical data obtained from two separate Phase I/IIa trials conducted in PCA (prostate cancer) and NSCLC (non-small cell lung carcinoma) patients have shown that the two-component mRNA vaccines are safe, well tolerated and highly immunogenic in humans.

The role of βIII-tubulin in non-small cell lung cancer patients treated by taxane-based chemotherapy

BACKGROUND

The aim of this study is to evaluate whether class III β-tubulin (TUBB3) expression could predict progression-free survival or overall survival in relapsed non-small cell lung cancer (NSCLC) patients treated with taxene-based chemotherapy.

METHODS

Immunohistochemistal staining was used to examine the expression of TUBB3 in resected lung tumor specimens obtained from 56 patients treated with platinum-based chemotherapy against recurrent tumors after curative resections. Excision repair cross-complementation group 1, breast cancer susceptibility gene 1, vascular endothelial growth factor, Ki-67, CD34, and p53 were also correlated with clinical features and outcome after treatment.

RESULTS

Of the 56 patients enrolled in the study, 29 were treated by carboplatin plus paclitaxel as first-line treatment, and 24 patients received docetaxel monotherapy as second- or third-line treatment. A positive TUBB3 expression is closely associated with a poor response to taxane-based chemotherapy. TUBB3 expression was an independent prognostic factor for predicting poor progression-free survival after docetaxel administration. However, TUBB3 expression could not predict outcome after carboplatin plus paclitaxel treatment. The other biomarkers tested were not independent prognostic factors for predicting outcome after taxane-based chemotherapy.

CONCLUSION

TUBB3 expression is associated with resistance to taxane-based chemotherapy and is an independent prognostic factor for predicting poor progression-free survival after docetaxel treatment alone. TUBB3 expression may be a predictive marker for chemoresistance to docetaxel in NSCLC with postoperative recurrent disease.

Phase II trial of capecitabine combined with docetaxel in previously treated patients with non-small cell lung cancer: A randomized controlled study

Docetaxel alone has been confirmed to be beneficial to patients with advanced previously treated non-small cell lung cancer (NSCLC). However, the duration and survival time is short. The study of two-agent combination regimens has important clinical significance. We conducted this randomized controlled phase II trial to comparatively evaluate the efficacy and side effects of capecitabine combined with docetaxel in previously treated patients with NSCLC. Patients with previously treated NSCLC who failed first-line chemotherapy were randomized into two groups; one received capecitabine combined with docetaxel (XT group) and the other received docetaxel alone (T group). Patients in the XT group received chemotherapy as follows: capecitabine 625 mg/m(2), p.o. bid, days 5-18; and docetaxel 30 mg/m(2), days 1 and 8, while patients in the T group received docetaxel 35 mg/m(2) on days 1 and 8. The primary endpoint was time to progression (TTP), and secondary endpoints were overall survival (OS), response rate (RR) and disease control rate (DCR). Forty-eight patients were recruited (23 in the XT group and 25 in the T group). TTP, median survival time (MST) and 1-year OS rate in the XT group and the T group were 7 months, 12 months, 47.6% and 3 months, 12 months, 39.6%, respectively. The TTP in the XT group was significantly longer compared to that in the T group (χ(2)=4.763, p=0.029). The RR and DCR in the XT group and T group were 13.0% (3/23), 78.3% (18/23) and 12.0% (3/25), 76% (19/25), respectively. The difference was not significant (p>0.05). The major side effects observed in the two groups were neutropenia, fatigue and nausea, and toxicities were mild to modest. No severe cases of hand-foot syndrome were observed in the XT group. In conclusion, compared with docetaxel alone, capecitabine combined with docetaxel for patients with previously treated NSCLC achieved a significantly longer TTP and this regimen was well tolerated. The relatively high median TTP, 1-year OS rate and DCR encourage further evaluation of this regimen in a randomized phase III trial.

Tubulin-interactive natural products as anticancer agents

This review provides an overview of the discovery, structures, and biological activities of anticancer natural products that act by inhibiting or promoting the assembly of tubulin to microtubules. The emphasis is on providing recent information on those compounds in clinical use or in advanced clinical trials. The vinca alkaloids, the combretastatins, NPI-2358, the halichondrin B analogue eribulin, dolastatin 10, noscapine, hemiasterlin, and rhizoxin are discussed as tubulin polymerization inhibitors, while the taxanes and the epothilones are the major classes of tubulin polymerization promoters presented, with brief treatments of discodermolide, eleutherobin, and laulimalide. The challenges and future directions of tubulin-interactive natural products-based drug discovery programs are also discussed briefly.

Class III beta-tubulin expression in tumor cells is correlated with resistance to docetaxel in patients with completely resected non-small-cell lung cancer

OBJECTIVE

To assess the relationship between in vitro chemosensitivity evaluated by the histoculture drug response assay (HDRA) and the expression of beta-tubulin isotypes in tumors of patients with completely resected NSCLC in order to determine the predictive value of beta-tubulin in chemotherapy for NSCLC.

METHODS

Expression of beta-tubulin isotypes was immunohistochemically analyzed in a series of 58 tumor samples from patients with completely resected NSCLC. The sensitivity of individual tumors to anticancer agents was evaluated by HDRA.

RESULTS

Class III beta-tubulin expression by tumor cells was significantly correlated with resistance to docetaxel (p=0.0250), but not related with resistance to gemcitabine. Patient characteristics (age, gender, histology, and stage) were not associated with class III beta-tubulin expression.

CONCLUSION

An abundance of class III beta-tubulin in tumor cells could be a biomarker for resistance to docetaxel in patients with completely resected NSCLC.

The anti-tumor efficacy of a GM-CSF-secreting tumor cell vaccine is not inhibited by docetaxel administration

Docetaxel has demonstrated therapeutic efficacy against breast, prostate, and ovarian cancer and other solid tumors. The tumoricidal activity of docetaxel is mainly attributed to its ability to block microtubule depolymerization, thus inducing G(2)-M arrest and apoptosis. Mounting evidence indicates that docetaxel also possesses immunomodulatory activity such as augmenting macrophage and lymphokine activated killer activity and inducing pro-inflammatory cytokines, suggesting that docetaxel may be a good chemotherapeutic agent to combine with cancer immunotherapies, assuming that it does not inhibit the vaccine-induced immune response. The anti-tumor activity of the combination of docetaxel and a GM-CSF-secreting B16F10 tumor cell vaccine (B16.GM) was evaluated in the murine B16 melanoma model. Dose levels of docetaxel and the B16.GM vaccine known to be ineffective when used as single agents were selected. Three iv treatments of 6 mg/kg docetaxel per injection given on days 5, 9, and 13 after tumor challenge or a single vaccination with 2-3 x 10(6) B16.GM cells on day 3 were ineffective at inhibiting tumor growth when used as single agents [median survival time (MST)=24 days in both treatment groups and in control animals]. However, combination of docetaxel and B16.GM vaccine significantly delayed tumor growth, increasing MST to 45 days. A similar improvement in anti-tumor efficacy was observed using multiple treatment cycles of the B16.GM vaccine/docetaxel combination. Administration of docetaxel every 4 days between bi-weekly B16.GM vaccinations increased the median survival of tumor-bearing mice from 31 to 52 days compared to multiple B16.GM vaccinations alone. In summary, these data demonstrate that rather than inhibiting the anti-tumor effects of a GM-CSF-secreting tumor cell vaccine, docetaxel combined with a whole cell vaccine significantly inhibits tumor growth, increases survival time and does not impede T-cell activation in the murine B16F10 melanoma tumor model. GM-secreting tumor cell vaccines in combination with docetaxel may represent a new strategy for combining chemo and immunotherapy for cancer.

Cytotoxicity of Docetaxel (Taxotere®) Used as a Single Agent and in Combination with Radiation in Human Gastric, Cervical and Pancreatic Cancer Cells

BACKGROUND

Docetaxel (Taxotere) has gained increasing attention in clinical applications. We investigated the cytotoxic and radiosensitizing potential of docetaxel at nanomolar concentrations in six cell lines derived from tumors that rarely respond to radiation or chemotherapy, with special consideration of mechanisms of resistance, including the p53 mutational status.

METHODS

Cells derived from carcinomas of the human stomach (p53 mutant Hs746T, p53 wild type AGS), cervix (p53 wild type CaSki, p53 mutant HeLa) or pancreas (p53 mutant BxPC3 and Capan-1) were treated for 24 h with docetaxel at various concentrations (0.1-5 nM) to obtain drug doses for inhibiting clonogenicity by approximately 50% (IC(50)). Cells were X-irradiated without docetaxel or after 24 h of docetaxel treatment at IC(50). Radiation doses ranged from 0 up to 10 Gy. Mitotic index, multinucleation, apoptosis and necrosis after 24 h of drug exposure at 1 nM were quantified in representative gastric and cervical cell lines by fluorescence microscopy.

RESULTS

Docetaxel treatment for 24 h resulted in a dose-dependent loss of clonogenicity, with 1.0 or 0.3 nM producing approximately 50% survival of gastric or cervix and pancreatic cells, respectively. After correction for the drug toxicity, the combination of isoeffective concentrations of docetaxel with graded X-ray doses resulted either in a moderate synergy or additivity. The dose reduction factors at the 50 and 20% survival levels were statistically greater than those for Hs746T or AGS cells. For CaSki, HeLa, BxPC3 or Capan-1 cells, the dose reduction factors were statistically not different from unity.

CONCLUSION

Docetaxel was active against tumor cells of different origins. Combined effects of docetaxel and radiation were at least additive and depended on the intrinsic sensitivity to drug alone. There was no significant evidence of drug-induced mitotic arrest. Compared to drug-resistant gastric cells, exposure to the drug alone of drug-sensitive cervical cells resulted in more severe multinucleation. The p53 status did not contribute directly to the effect of drug alone or in combination with radiation.

Docetaxel-based induction therapy prior to radiotherapy with or without docetaxel for non-small-cell lung cancer

This trial aimed to assess the feasibility and tumour control of concurrent chemoradiotherapy or radiotherapy alone after docetaxel-based induction chemotherapy in locally advanced non-small-cell lung cancer (NSCLC). Patients with stage IIIA/IIIB NSCLC received two 21-day cycles of induction chemotherapy with docetaxel (85 mg m(-2), day 1) plus cisplatin (40 mg m(-2), days 1 and 2). Patients without disease progression on day 43 were randomised to radiotherapy (2 Gy for 5 days week(-1); total 60 Gy) alone or with docetaxel 20 mg m(-2) once weekly every 6 weeks. Of 108 patients who received induction chemotherapy, 104 were evaluable for response. After induction chemotherapy, the overall response rate (ORR) was 44%; 91 (88%) patients had no disease progression and 89 were subsequently randomised to local treatment. After randomised therapy, the ORR was 53% (chemoradiotherapy 58%; radiotherapy 48%). Median survival and time to progression were 14.9 and 7.8 months, respectively, for chemoradiotherapy and 14.0 and 7.5 months, respectively, for radiotherapy. The most common toxicities during induction chemotherapy and randomised therapy were grades 3-4 neutropenia and grade 3 lymphocytopenia, respectively. Docetaxel-cisplatin induction therapy followed by concurrent docetaxel and thoracic radiotherapy is a feasible treatment option, showing good clinical activity and tolerability, for locally advanced NSCLC.

Induction of tubulin by docetaxel is associated with p53 status in human non small cell lung cancer cell lines

Docetaxel (DOC), a member of the taxane family of anticancer drugs, binds to tubulin and produces unnaturally stable microtubules that induce cell death. DOC is used clinically alone or in combination with other compounds to treat advanced stages of cancer. We have treated the human lung cancer cell lines A549 and H1299 and human cervical cancer HeLa cells with low concentrations of DOC to characterize the response of beta-tubulin isotypes and p53 genes. The relationship between p53 function and DOC, acting through a microtubule-based mechanism, was examined. We found that after 18-hr treatment with DOC, beta-tubulin gene transcription was enhanced in p53-null H1299 cells but not in A549 cells. Also, p53 RNA was strongly induced in the A549 cells. In addition, beta-tubulin levels also increased in the H1299 cells after the DOC treatment. Further demonstrating an association of DOC treatment with p53 and beta-tubulin, inhibition of p53 expression by interference RNA in A549 cells showed increasing beta-tubulin gene expression with DOC treatment. We also selected a clone from the H1299 cells that stably expressed p53, examined the beta-tubulin expression after DOC treatment and found an inhibition of beta-tubulin induction in these p53-expressing cells. Our data suggest that the initial response of cells to DOC treatment involves p53; alternatively, in the absence of p53, tubulins may be transactivated. Selection of the DOC-resistant A549 cells showed beta-tubulin expression was increased, in contrast to the initial response to the DOC treatment. From the initial and selection responses of beta-tubulin in cancer cells, it appears that there is a p53-associated beta-tubulin expression as a result of the DOC treatment.

Phase I and pharmacokinetic study of docetaxel combined with melphalan and carboplatin, with autologous hematopoietic progenitor cell support, in patients with advanced refractory malignancies

The purpose of this study was to define the maximal tolerated dose (MTD), extramedullary toxicities, and pharmacokinetics of docetaxel combined with high-dose melphalan and carboplatin with autologous hematopoietic progenitor cell support. Fifty-nine patients with advanced refractory malignancy (32 breast cancer, 10 non-Hodgkin lymphoma, 6 germ cell tumors, 4 Hodgkin disease, 4 ovarian cancer, 2 sarcoma, and 1 unknown primary adenocarcinoma) with a median of 3 prior chemotherapy regimens and a median of 3 organs involved were enrolled. Treatment included docetaxel (150-550 mg/m2 infused over 2 hours on day -6), melphalan (150-165 mg/m2 infused over 15 minutes from day -5 to -3), and carboplatin (1000-1300 mg/m2 as a 72-hour continuous infusion from day -5). Five patients died from direct regimen-related organ toxicity (2 capillary leak syndrome, 2 enterocolitis, and 1 hepatic toxicity), and 1 additional patient died from pulmonary aspergillosis. The docetaxel MTD was defined as 400 mg/m 2 , combined with melphalan (150 mg/m2 ) and carboplatin (1000 mg/m2 ). The MTD cohort was expanded to enroll a total of 26 patients, 1 of whom died from toxic enterocolitis. The remaining 25 patients presented the following extramedullary toxicity profile, which was manageable and largely reversible: stomatitis, myoarthralgias, peripheral neuropathy, gastrointestinal and cutaneous toxicities, and syndrome of inappropriate antidiuretic hormone secretion. Docetaxel exhibited linear pharmacokinetics in the dose range tested (150-550 mg/m2 ). Pharmacodynamic correlations were noted between the docetaxel area under the curve and peripheral neuropathy or stomatitis. The response rate among 38 patients with measurable disease was 95%, with 47% complete responses. At a median follow-up of 26 months (range, 7-72 months), the 3-year event-free survival and overall survival were 26% and 36%, respectively. In conclusion, a 4-fold dose escalation of docetaxel, combined with melphalan and carboplatin, is feasible with autologous hematopoietic progenitor cell support. The notable activity of this regimen in treatment-refractory patients warrants its further evaluation.