Somatostatin receptor-mediated tumor-targeting drug delivery using octreotide-PEG-deoxycholic acid conjugate-modified N-deoxycholic acid-O, N-hydroxyethylation chitosan micelles

Development of octreotide-conjugated polymeric prodrug of bufalin for targeted delivery to somatostatin receptor 2 overexpressing breast cancer in vitro and in vivo

“…SSTR2 overexpressing breast cancer cell line MCF-7 cells were used to examine their physiochemical properties, cellular uptake, ability to induce apoptosis and suppress proliferation of tumor cells, and in vivo anticancer effects. 4,31,36,37 Throughout the studies, the effects of prodrugs were compared with those of native-free BUF.…”

“…In addition, the introduction of tumor-targeting moiety Oct is assumed to enhance the accumulation of drugs in the cancerous tissue via receptormediated endocytosis. 36 …”

“…This result reveals that attaching Oct onto the polymer backbone might play an important role at lower BUF concentration in enhancing the cytotoxicity by promoting surface binding and cellular entry via receptor-mediated endocytosis mechanism (Figure 1). 4,31,36,37 However, by increasing the BUF dosage, the anticancer difference between P(OEGMA-co-BUF) and P(OEGMA-co-BUF-co-Oct) decreased, although they still performed better than free BUF. The main reason might be related to the relative amount of SSTR2 on the membrane surface of MCF-7 cells and Oct peptide on the surface of nanoparticles.…”

“…[29][30][31] Octreotide (Oct) is an octapeptide analog of endogenous somatostatin and mainly binds to SSTRs, especially SSTR2 and SSTR5, in breast cancer; hence, it may be possible to employ Oct as a potential ligand in receptor-mediated nanodelivery system. [32][33][34][35][36] Huang et al reported the fabrication of PTX-Oct conjugate and explored its anticancer performance against human breast MCF-7 carcinoma cells. 4 It was showed that PTX-Oct exhibited less toxicity as well as comparable anticancer efficacy in comparison with that of free PTX.…”

“…38 After that they further developed a breast cancer and human embryonic lung fibroblast-targeting drug delivery system by using Oct-PEG-deoxycholic acid conjugate-modified N-deoxycholic acid-O,N-hydroxymethylation chitosan micelles, indicating promising potentials in anticancer drug delivery for targeted cancer therapy. 36 It is worthy of noting that in addition to physically encapsulating drugs by nanoparticles, polymeric prodrug is another promising strategy owing to its intrinsic advantages such as passive targeting via the EPR effect, increased circulation time, improved water solubility, and tunable and well-defined drug content. [18][19][20][21][22][23][39][40][41][42][43][44] Besides, premature/burst drug release, which is one of the most common shortcomings of encapsulating method, can be effectively addressed.…”