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Srivastava AK, Bhatnagar P, Singh M, et al. Int J Nanomedicine. 2013;8:1451–1462.Upon reviewing the article, the authors noticed the PCR gel images were difficult to view in Figures 6 and 7 (pages 1458 and 1459). The authors confirm that the higher resolution figures provided do not impact the findings of the study. Figures 6 and 7 should be presented as follows:Read the original article

Singh M, Bhatnagar P, Mishra S, Kumar P, Shukla Y, Gupta KC. PLGA-encapsulated tea polyphenols enhance the chemotherapeutic efficacy of cisplatin against human cancer cells and mice bearing Ehrlich ascites carcinoma. International Journal of Nanomedicine. 2015;10:6789–6809.The Editor-in-Chief and Publisher of International Journal of Nanomedicine wish to retract the published article.Concerns were raised about the possibility of image manipulation and duplication in the published article. The alleged image manipulation relates to the Western blot bands presented in:● Figure 6A p-NF-κB and p-IκB-α● Figure 6A, Figure S3A and S3C β-actin bands● Figure S3C Bax and Bcl-2It was also found that images in Figure 4 (TF-NP + CDDP; EGCG + CDDP and EGCG-NP + CDDP) were duplicated from images presented in Figure 5 of the article: Singh M, Bhui K, Singh R, Shukla Y. Tea polyphenols enhance cisplatin chemosensitivity in cervical cancer cells via induction of apoptosis. Life Sciences. 2013;93:7–16. doi: 10.1016/j.lfs.2013.02.001.The authors were contacted but were unable to provide a satisfactory explanation for the alleged image duplication and could not supply satisfactory revisions for the article. The Director of CSIR-Indian Institute of Toxicology Research (CSIR-IITR) was contacted and was very helpful throughout our investigation. The Editor-in-Chief determined the findings and conclusions presented in the study were no longer upported.This retraction relates to this paper

Madhulika Singh,1 Priyanka Bhatnagar,2 Sanjay Mishra,1 Pradeep Kumar,2 Yogeshwer Shukla,1 Kailash Chand Gupta1,2 1CSIR-Indian Institute of Toxicology Research, Lucknow, 2CSIR-Institute of Genomics and Integrative Biology, Delhi University Campus, Delhi, India Abstract: The clinical success of the applicability of tea polyphenols awaits efficient systemic delivery and bioavailability. Herein, following the concept of nanochemoprevention, which uses nanotechnology for enhancing the efficacy of chemotherapeutic drugs, we employed tea polyphenols, namely theaflavin (TF) and epigallocatechin-3-gallate (EGCG) encapsulated in a biodegradable nanoparticulate formulation based on poly(lactide-co-glycolide) (PLGA) with approximately 26% and 18% encapsulation efficiency, respectively. It was observed that TF/EGCG encapsulated PLGA nanoparticles (NPs) offered an up to ~7-fold dose advantage when compared with bulk TF/EGCG in terms of exerting its antiproliferative effects and also enhanced the anticancer potential of cisplatin (CDDP) in A549 (lung carcinoma), HeLa (cervical carcinoma), and THP-1 (acute monocytic leukemia) cells. Cell cycle analysis revealed that TF/EGCG-NPs were more efficient than bulk TF/EGCG in sensitizing A549 cells to CDDP-induced apoptosis, with a dose advantage of up to 20-fold. Further, TF/EGCG-NPs, alone or in combination with CDDP, were more effective in inhibiting NF-κB activation and in suppressing the expression of cyclin D1, matrix metalloproteinase-9, and vascular endothelial growth factor, involved in cell proliferation, metastasis, and angiogenesis, respectively. EGCG and TF-NPs were also found to be more effective than bulk TF/EGCG in inducing the cleavage of caspase-3 and caspase-9 and Bax/Bcl2 ratio in favor of apoptosis. Further, in vivo evaluation of these NPs in combination with CDDP showed an increase in life span (P

Amit Kumar Srivastava,1 Priyanka Bhatnagar,2 Madhulika Singh,1 Sanjay Mishra,1 Pradeep Kumar,2 Yogeshwer Shukla,1 Kailash Chand Gupta1,2 1Proteomics Laboratory, Indian Institute of Toxicology Research (CSIR), Lucknow, India; 2Nucleic Acid Research Laboratory, Institute of Genomics and Integrative Biology (CSIR), Delhi University Campus, India Abstract: In spite of proficient results of several phytochemicals in preclinical settings, the conversion rate from bench to bedside is not very encouraging. Many reasons are attributed to this limited success, including inefficient systemic delivery and bioavailability under in vivo conditions. To achieve improved efficacy, polyphenolic constituents of black (theaflavin [TF]) and green (epigallocatechin-3-gallate [EGCG]) tea in poly(lactide-co-glycolide) nanoparticles (PLGA-NPs) were entrapped with entrapment efficacy of ~18% and 26%, respectively. Further, their preventive potential against 7,12-dimethylbenzanthracene (DMBA)-induced DNA damage in mouse skin using DNA alkaline unwinding assay was evaluated. Pretreatment (topically) of mouse skin with either TF or EGCG (100 µg/mouse) doses exhibits protection of 45.34% and 28.32%, respectively, against DMBA-induced DNA damage. However, pretreatment with TF-loaded PLGA-NPs protects against DNA damage 64.41% by 1/20th dose of bulk, 71.79% by 1/10th dose of bulk, and 72.46% by 1/5th dose of bulk. Similarly, 51.28% (1/20th of bulk), 57.63% (1/10th of bulk), and 63.14% (1/5th of bulk) prevention was noted using EGCG-loaded PLGA-NP doses. These results showed that tea polyphenol-loaded PLGA-NPs have ~30-fold dose-advantage than bulk TF or EGCG doses. Additionally, TF- or EGCG-loaded PLGA-NPs showed significant potential for induction of DNA repair genes (XRCC1, XRCC3, and ERCC3) and suppression of DNA damage responsive genes (p53, p21, MDM2, GADD45α, and COX-2) as compared with respective bulk TF or EGCG doses. Taken together, TF- or EGCG-loaded PLGA-NPs showed a superior ability to prevent DMBA-induced DNA damage at much lower concentrations, thus opening a new dimension in chemoprevention research. Keywords: DNA alkaline unwinding assay, mouse skin, DNA repair