peptides with experimental and structural information, making use of literature and patents. Although plethora of papers has been published on therapeutic potential of tumor homing or targeting peptide in anti-cancer drug delivery and development, results have not come up to the expectations. We hope that this collection of tumor homing peptides will be very helpful to researchers to design novel peptides, which can be used further for developing novel anti- cancer drugs. In addition, TumorHoPe will also be useful for the generation of prediction models for novel tumor homing peptides. The understanding of the role of amino acids of tumor homing peptides is important for their rational drug designing. We have integrated various analysis tools, which can be exploited by users to search and modify their peptides in order to enhance the specificity of the query peptides. Since most of the tumor homing peptides bind to particular receptors present on tumor cells, structure of these peptides may play an important role in their binding to their receptors. Therefore, we have predicted 3D structures of all the peptides. Users can exploit this information for docking or molecular dynamics of the peptide-receptor complex. We anticipate that this thorough and comprehensive database will be extended to effective completeness and then maintained and its References 1. Blanco E, Hsiao A, Mann AP, Landry MG, Meric-Bernstam F, et al. (2011) Nanomedicine in cancer therapy: innovative trends and prospects. Cancer Sci 102: 1247–1252. 2. Jemal A, Bray F, Center MM, Ferlay J, Ward E, et al. (2011) Global cancer Statistics . CA Cancer J Clin 61: 69–90. 3. Tang Y, Lei T, Manchanda R, Nagesetti A, Fernandez-Fernandez A, et al. (2010) Simultaneous delivery of chemotherapeutic and thermal-optical agents to cancer cells by a polymeric (PLGA) nanocarrier: an in vitro study. 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Laakkonen P, Vuorinen K (2010) Homing peptides as targeted delivery vehicles. Integr Biol (Camb) 2: 326–337. 11. Corti A, Pastorino F, Curnis F, Arap W, Ponzoni M, et al. (2011) Targeted drug delivery and penetration into solid tumors. Med Res Rev. 12. Karmali PP, Kotamraju VR, Kastantin M, Black M, Missirlis D, et al. (2009) Targeting of albumin-embedded paclitaxel nanoparticles to tumors. Nanome- dicine 5: 73–82. 13. Engel JB, Schally AV, Dietl J, Rieger L, Honig A (2007) Targeted therapy of breast and gynecological cancers with cytotoxic analogues of peptide hormones. Mol Pharm 4: 652–658. Tumor Homing Peptides Repository content expanded, with constantly enhanced search and analysis features. Submission and Update of TumorHoPe The online data submission tool allows a user to submit a newly identified tumor homing peptide in the TumorHoPe database. However, before including in TumorHoPe, we will confirm the validity of new entry in order to maintain the quality. 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Rashid M, Singla D, Sharma A, Kumar M, Raghava GP (2009) Hmrbase: a database of hormones and their receptors. BMC Genomics 10: 307. 26. Ru B, Huang J, Dai P, Li S, Xia Z, et al. (2010) MimoDB: a new repository for mimotope data derived from phage display technology. Molecules 15: 8279–8288. 27. Thomas S, Karnik S, Barai RS, Jayaraman VK, Idicula-Thomas S (2009) CAMP: a useful resource for research on antimicrobial peptides. Nucleic Acids Res 38: D774–780. 28. Brahmachary M, Krishnan SP, Koh JL, Khan AM, Seah SH, et al. (2004) ANTIMIC: a database of antimicrobial sequences. Nucleic Acids Res 32: D586–589. PLoS ONE | www.plosone.org 6 April 2012 | Volume 7 | Issue 4 | e35187