Efficacy of dual-functional liposomes containing paclitaxel for treatment of lung cancer
Authors: Hong Ma
Jing Wu
Qing Wang
Zhi-Ju Tian
Hong-Mei Cao
Rong-Hua Wang
Bo Jin
Journal: Oncology Reports (2015)
Discipline: CLINICAL MEDICINE
Keywords: dual-ligand liposomal delivery system; paclitaxel; lung cancer; peptide; T7
Affiliations: Department of Cardiothoracic Surgery, People's Hospital of Zhangqiu, Zhangqiu, Shandong 250200, P.R. China., Pharmacy Intravenous Admixture Services, People's Hospital of Zhangqiu, Zhangqiu, Shandong 250200, P.R. China., Department of Orthopedic Surgery, People's Hospital of Zhangqiu, Zhangqiu, Shandong 250200, P.R. China., Department of Oral Pendulum Medicine, People's Hospital of Zhangqiu, Zhangqiu, Shandong 250200, P.R. China., Pharmacy Intravenous Admixture Services, The Second Hospital of Shandong University, Jinan, Shandong 250033, P.R. China.

Abstract:  This study was mainly focused on the development of a dual-ligand liposomal delivery system for targeting the delivery of paclitaxel (PTX) to lung cancer. The specific ligand peptide HAIYPRH (T7) and the cationic cell-penetrating peptide TAT were connected with phospholipid via a polyethylene glycol (PEG) spacer to prepare the dual-ligand liposomes (T7/TAT-LP-PTX). Physicochemical characterizations of T7/TAT-LP-PTX, such as particle size, ζ potential, morphology, encapsulation efficiency, and in vitro PTX release, were also evaluated. In the cellular uptake study, the T7/TAT-LP endocytosed by the A549 cells was 2.26-, 3.48- and 8.56-fold higher than TAT-LP, T7-LP and LP, respectively. The IC50 values of TAT-LP-PTX, T7-LP-PTX and LP-PTX were much higher than those of T7/TAT-LP-PTX, respectively. The homing specificity of T7/TAT-LP was evaluated on the tumor spheroids, which revealed that T7/TAT-LP was more efficaciously internalized in tumor cells than TAT-LP, T7-LP and LP, respectively. Compared to LP, TAT-LP and T7-LP, T7/TAT-LP showed the strongest cell uptake property, and the highest accumulation ability in tumor spheroids in vitro. In the in vivo study, the T7/TAT-LP-PTX exhibited the best inhibitory effect of tumor growth for A549-bearing mice. Collectively, these results suggested that T7/TAT-LP-PTX is a promising drug delivery system for the treatment of lung cancer. 

Retracted: Yes

PubPeer comments:
 Same images used in two papers to illustrate the targeting of two different types of nanoparticles to s.c. A549 tumors in nude mice (upper picture) and to cells in vitro (lower picture). Intriguing is that there are no overlapping authors or institutes. ![file] ![file] , 
 Interesting that neither paper s set of images is a subset of the other -- both image selections come from an unknown, all-inclusive source. I eagerly await the discovery of more papers, illustrated with further selections from that Ur-text. Could both sets of authors have outsourcedthe production of the papers to an outside company (a paper mill)? , 
 Another appearance of the fluroescing cells, in a new arrangement: ![file] Source:  [Transferrin and cell-penetrating peptide dual-functioned liposome for targeted drug delivery to glioma]  . Zheng et al (2015), Int J Clin Exp Med. Publisher is  e-Century , considered predatory. , 
 #1 This paper begins as follows: blockquote Introduction Lung cancer is characterized by uncontrolled cell growth in lung tissues leading to metastasis, invasion of adjacent tissue and infiltration beyond the lungs. Lung cancer was responsible for over 0.15 million deaths in the United States in 2010, with over 0.2 million cases registered annually (1). Although surgery is a preferred method of cancer removal, it cannot remove the tissue completely and is required to be supplemented by multi-drug chemotherapy and or radiation as preferred treatment of choice. Etoposide (ETP) and docetaxel (DTX) are the current drugs of choice along with doxorubicin, carboplatin and cisplatin for lung cancer treatment (2). However, these preferred chemotherapeutic agents used in cancer therapy have shown limited therapeutic action. blockquote  Transferrin-conjugated doxorubicin-loaded lipid-coated nanoparticles... (Guo et al.) begins blockquote Introduction Lung cancer is characterized by uncontrolled cell growth in lung tissues, which results in metastasis, the invasion of tissues adjacent to the lesion and infiltration beyond the lungs. In 2010, lung cancer accounted for 0.15 million deaths in the USA, and 0.2 million cases are registered annually (1). Despite surgery being the preferred method for the removal of cancer, it cannot completely excise the affected tissue and supplementary multi-drug chemotherapy or radiation may be required. The current drugs of choice for lung cancer therapy include etoposide, docetaxel, doxorubicin (DOX), carboplatin and cisplatin (2). However, limited therapeutic action has been demonstrated by the preferred chemotherapeutic agents for cancer therapy. blockquote Both were written by following the same script, varying the wording just enough to fly under the Turnitin radar. The parallelism is notable in the Methods: blockquote Other chemicals and reagents were of analytical grade and obtained commercially. BALB c male athymic nude mice (~20 g) were purchased from the Experiment Animal Center of Shandong University (Jinan, China). blockquote versus blockquote Other chemicals and reagents were of analytical grade and obtained commercially. BALB c male athymic nude mice, ~20 g in weight, were purchased from the Experimental Animal Center of Tianjin Medical University (Heping, Tianjin, China). blockquote while in  Transferrin and cell-penetrating peptide dual-functioned liposome for targeted drug delivery to glioma , Zheng et al (see comment #3), blockquote Other chemicals and reagents were of analytical grade and obtained commercially. BALB c male athymic nude mice (about 20 g) were purchased from the Experiment Animal Center of Sichuan University (P. R. China). blockquote Another publication from Oncology letters follows the same structure -- Chen et al. (2015),  [Effect of integrin receptor-targeted liposomal paclitaxel for hepatocellular carcinoma targeting and therapy]  -- as if following the same script. It may merit closer attention. blockquote All other chemicals and reagents were of analytical grade and obtained commercially. BALB c male athymic nude mice (weight, ~20 g; n=40) were purchased from the Experimental Animal Center of Sichuan University (Chengdu, China). blockquote , 
 More: Wu et al. (2015),  [Development of synthetic of peptide-functionalized liposome for enhanced targeted ovarian carcinoma therapy]  -- e-Century again -- followed the same script, this time with ovarian cancer as the target, so the male mice became female. blockquote Other chemicals and reagents were of analytical grade and obtained commercially. BALB c female athymic mice (about 20 g) were purchased from the Experiment Animal Center of Zhengzhou University (P. R. China). blockquote In Wu et al., blockquote In the last two decades, liposomal drug delivery systems hold extraordinary potential for delivery of therapeutics to tumor, various strategies have been used to improve their targeting specificity and cellular uptake. blockquote Chen et al.: blockquote Over the last two decades, liposomal drug delivery systems have exhibited significant potential for the delivery of therapeutic agents to tumors, and various strategies have been used to improve their targeting specificity and cellular uptake. blockquote Wang et al.: blockquote Over the last two decades, liposomal drug delivery systems have exhibited significant potential for the delivery of therapeutic agents to tumors, and various strategies have been used to improve their targeting specificity and cellular uptake. blockquote , 
 #5 I ve already quoted from the second paragraph of Wang et al., but here is a longer excerpt: blockquote In the last two decades, liposomal drug delivery systems hold extraordinary potential for delivery of therapeutics to tumor, and various strategies have been used to improve their targeting specificity and cellular uptake. PEGylation has been extensively employed to enhance the accumulation of liposomes in tumor tissues through enhanced permeability and retention (EPR) effects, which was the passive form of targeting (3). In attempts to increase the specificity of interaction between liposomes and tumor cells, recent efforts in the liposome field have focused on the development of active tumor-targeted liposomes, which were modified with specific ligands such as TF (4), folic acid (5), peptides (6u20139) or antibodies (10u201312), and could selectively recognize and bind to the specific overexpressed receptor in tumor cells, resulting in increased targeting efficiency and less toxicity. ... However, the presence of receptor-targeting moiety alone on PEGylated liposomes limits the cellular uptake of liposomes due to receptor saturation (18,19). Considering that an ideal tumor-targeted drug delivery system should selectively targets delivery drugs to the tumor and delivers the drugs into tumor cells with high efficacy, the receptor saturation should also be overcome. The cell-penetrating peptides (CPPs) conjugated to the surface of liposomes have been widely investigated under in vitro conditions to increase the intracellular delivery of drugs (20). Additionally, the cationic cell-penetrating peptide CPP (TAT) derived from the HIV-1 protein TAT may facilitate the intracellular delivery of cargoes with various sizes and physicochemical properties (21u201323). Liposomes modified with TAT may deliver the cargoes into cells with high efficiency through an unsaturated and receptor transporter-independent pathway (24). In the present study, we employed a dual mechanistic approach for targeting TFR on tumor cells and further improving the cellular uptake of the targeted delivery vehicle. We combined the receptor targeting property of T7 with the enhanced cell uptake effect of TAT to improve the transport of desired cargoes to the tumor. blockquote This occurred previously in Tang et al. (2013),  [Synergistic targeted delivery of payload into tumor cells by dual-ligand liposomes co-modified with cholesterol anchored transferrin and TAT]  (Int. J. Pharm): blockquote In the last two decades, liposomal drug delivery systems hold extraordinary potential for delivery of therapeutics to tumor, various strategies have been used to improve their targeting specificity and cellular uptake. PEGylation has been extensively employed to enhance the accumulation of liposomes in tumor tissues through enhanced permeability and retention (EPR) effects, which was the passive form of targeting. In attempts to increase the specificity of interaction between liposomes and tumor cells, recent efforts in the liposome field have been focusing on the development of the active tumor targeted liposomes, which were modified with some specific ligands such as TF, folic acid, peptides or antibodies, and could selectively recognize and bind to the specific receptor over-expressed on tumor cells, resulting in increased targeting efficiency and less toxicity. ... However, the presence of receptor-targeting moiety alone on PEGylated liposomes limits the cellular uptake of liposomes due to receptor saturation (Kibria et al., 2011; Sharma et al., 2012). Considering that an ideal tumor targeted drug delivery system should not only selectively targeted delivery drugs to tumor, but also deliver the drugs into tumor cells with high efficacy, the receptor saturation needed to be overcame. In previous studies, the cell-penetrating peptides (CPPs) conjugated to the surface of liposomes have been widely investigated under in vitro conditions for increasing the intracellular delivery of drugs (Wadia and Dowdy,2002). And the cationic cell-penetrating peptide CPP (TAT) derived from the HIV-1 protein TAT could facilitate the intracellular delivery of cargoes with various sizes and physicochemical properties(Banks et al., 2005; Brooks et al., 2005; Gupta et al., 2005). Liposomes modified with TAT could deliver the cargoes into cells with high efficiency via an unsaturated and receptor transporter independent pathway (Torchilin et al., 2001). Here we followed a dual mechanistic approach for targeting TFR on tumor cells and further improving the cellular uptake of the targeted delivery vehicle. We combined the receptor targeting property of TF with the enhanced cell uptake effect of TAT to improve the transport of desired cargoes to tumor. blockquote , 
 ![file] Here are the relationships I ve found. The references are: Cao Y, Zhou Y, Zhuang Q, Cui L, Xu X, Xu R, He X. Anti-tumor effect of RGD modified PTX loaded liposome on prostatic cancer. Int J Clin Exp Med. 2015 Aug 15;8(8):12182-91. eCollection 2015. PubMed PMID: 26550128; PubMed Central PMCID: PMC4612813. Chen L, Liu Y, Wang W, Liu K. Effect of integrin receptor-targeted liposomal paclitaxel for hepatocellular carcinoma targeting and therapy. Oncol Lett. 2015 Jul;10(1):77-84. Epub 2015 May 20. PubMed PMID: 26170980; PubMed Central PMCID: PMC4487032. Guo Y, Wang L, Lv P, Zhang P. Transferrin-conjugated doxorubicin-loaded lipid-coated nanoparticles for the targeting and therapy of lung cancer. Oncol Lett. 2015 Mar;9(3):1065-1072. Epub 2014 Dec 30. PubMed PMID: 25663858; PubMed Central PMCID: PMC4315058. Liu Y, Ran R, Chen J, Kuang Q, Tang J, Mei L, Zhang Q, Gao H, Zhang Z, He Q. Paclitaxel loaded liposomes decorated with a multifunctional tandem peptide for glioma targeting. Biomaterials. 2014 Jun;35(17):4835-47. doi: 10.1016 j.biomaterials.2014.02.031. Epub 2014 Mar 17. PubMed PMID: 24651033. Mei L, Fu L, Shi K, Zhang Q, Liu Y, Tang J, Gao H, Zhang Z, He Q. Increased tumor targeted delivery using a multistage liposome system functionalized with RGD, TAT and cleavable PEG. Int J Pharm. 2014 Jul 1;468(1-2):26-38. doi: 10.1016 j.ijpharm.2014.04.008. Epub 2014 Apr 5. PubMed PMID: 24709209 Tang J, Zhang L, Gao H, Liu Y, Zhang Q, Ran R, Zhang Z, He Q. Co-delivery of doxorubicin and P-gp inhibitor by a reduction-sensitive liposome to overcome multidrug resistance, enhance anti-tumor efficiency and reduce toxicity. Drug Deliv. 2016 May;23(4):1130-43. doi: 10.3109 10717544.2014.990651. Epub 2014 Dec 10. PubMed PMID: 25491241. Wang RH, Cao HM, Tian ZJ, Jin B, Wang Q, Ma H, Wu J. Efficacy of dual-functional liposomes containing paclitaxel for treatment of lung cancer. Oncol Rep. 2015 Feb;33(2):783-91. doi: 10.3892 or.2014.3644. Epub 2014 Dec 2. PubMed PMID: 25482610. Wu H, Yao L, Mei J, Li F. Development of synthetic of peptide-functionalized liposome for enhanced targeted ovarian carcinoma therapy. Int J Clin Exp Pathol. 2015 Jan 1;8(1):207-16. eCollection 2015. PubMed PMID: 25755707; PubMed Central PMCID: PMC4348858. Zheng C, Ma C, Bai E, Yang K, Xu R. Transferrin and cell-penetrating peptide dual-functioned liposome for targeted drug delivery to glioma. Int J Clin Exp Med. 2015 Feb 15;8(2):1658-68. eCollection 2015. PubMed PMID: 25932094; PubMed Central PMCID: PMC4402741. , 
 #7 Three papers in the interlinked cluster at the left of your diagram -- Liu c, Mei c, Tang c -- are from the same research group headed by Qin He, so they share a lot of authorship. Also they are built on earlier papers from the same group. So a level of similarity among those three is to be expected. Those papers from Qin He s group (and earlier ones) were published before the others on your list, as if the influence only goes one way. , 
 #7 i Wu H, Yao L, Mei J, Li F.  Development of synthetic of peptide-functionalized liposome for enhanced targeted ovarian carcinoma therapy. i It turns out that e-Century have published this **twice** -- one in Int J Clin Exp Med in [December 2014] , and then in Int J Clin Exp Pathol. in [January 2015](http: https: www.ncbi.nlm.nih.gov pubmed 25755707). Do not feel obliged to include both versions in your diagram. , 
 #7 Macrophthalmus Grandidieri has called attention to the repetition within Fig 8 of the present paper, in which the same cancer spheroid appears as the 2nd and 4th panels, i.e. after four hours of absorbing rhodamine-labeled TAT and T7-TAT liposomes respectively. ![file] , 
 ![file] Paper has been withdrawn , 
 Have they ever performed those experiment? That s what I feel suspicious , 
 #11 Thanks, Prof. Schiffelers, for starting the ball rolling. , 
 This all began with questions as to the origins of the mice that appeared in two independent papers: ![] Please consider Figure 9 from Mei et al. (2014),  [Increased tumor targeted delivery using a multistage liposome system functionalized with RGD, TAT and cleavable PEG]  : ![] Clearly not identical but they give the impression of being photographed in the same conditions, perhaps from the same series. On its own this impression would not be dispositive, but Qin He s laboratory -- the source of Mei et al. -- is enmeshed in a network of papers linked by shared images. See https: pubpeer.com publications CB66A06CB50B578328261C497A3349 https: pubpeer.com publications 32D122DA655FAC07E1B23D8520FFBF , 
 Link for #11: Retracted [26 September 2017] -------------------------------------------------- Following the publication of this article, the authors find that they are not able to reproduce the results presented in this paper. Consequently, the authors have decided to retract this paper from publication. All of the authors agree to this retraction. The authors sincerely regret this decision, and apologize to the Editor and to the readership of the Journal for any inconvenience caused. , 
 There is a wave of interest in this paper in Chinese media, after someone observed that the e-mail address for the putative corresponding author (529827419@qq.com) has also featured in a number of other papers (in Chinese-language journals), all from different authors at different institutions. ![file] Speculation naturally followed that this was actually the e-address of a paper-writing service. Some Chinese observers went on to notice the extent of text overlap between this paper and others, as reported in various comments above. E.g. https: kknews.cc health 5nrqnok.html , 
 #16 When you search for @qq.com 5000 papers surface. all with numbers@qq.com. Is this a very popular mail account in China? Or are these a sort of ORCID IDs at the paper mill? , 
 My understanding is that qq.com is a popular email provider in China.  [QQ, which is owned by the Chinese tech giant Tencent, is a messaging application similar to Skype] . In China and parts of Asia, qq.com is like what gmail.com, yahoo.com or outlook.com are to the US in terms of providing email, messaging and communication services. It provides email accounts with numerical labels (which makes sense when you think about it). The vast majority of %%%%%@qq.com e-addresses are legitimate, but the service is also popular with people who want disposable single-use e-addresses, for spamming or for submitting fabricated papers to journals. , 
 Fig 8 again: ![] Figs 3 and 4 from  Preparation and in-vitro anti-tumor activity of doxirubicin and embelin co-loaded liposomes decorated with transferrin ([Quan Ye, 2014] ). From a Chinese-language journal. ![file] ,