GE11-modified liposomes for non-small cell lung cancer targeting: preparation, ex vitro and in vivo evaluation

Abstract

Non-small cell lung cancer (NSCLC) is a serious threat to human health, and 40%–80% of NSCLCs express high levels of epidermal growth factor receptor (EGFR). GE11 is a novel peptide and exhibits high affinity for EGFR binding. The aim of this study was to construct and evaluate GE11-modified liposomes for targeted drug delivery to EGFR-positive NSCLC. Doxorubicin, a broad-spectrum antitumor agent, was chosen as the payload. GE11 was conjugated to the distal end of DSPE-PEG 2000 -Mal by an addition reaction with a conjugation efficiency above 90%. Doxorubicin-loaded liposomes containing GE11 (GE11-LP/DOX) at densities ranging from 0% to 15% were prepared by combination of a thin film hydration method and a post insertion method. Irrespective of GE11 density, the physicochemical properties of these targeted liposomes, including particle size, zeta potential, and drug entrapment efficiency, were nearly identical. Interestingly, the cytotoxic effect of the liposomes on A549 tumor cells was closely related to GE11 density, and liposomes with 10% GE11 had the highest tumor cell killing activity and a 2.6-fold lower half maximal inhibitory concentration than that of the nontargeted counterpart (PEG-LP/DOX). Fluorescence microscopy and flow cytometry analysis revealed that GE11 significantly increased cellular uptake of the liposomes, which could be ascribed to specific EGFR-mediated endocytosis. It was found that multiple endocytic pathways were involved in entry of GE11-LP/DOX into cells, but GE11 assisted in cellular internalization mainly via the clathrin-mediated endocytosis pathway. Importantly, the GE11-modified liposomes showed enhanced accumulation and prolonged retention in tumor tissue, as evidenced by a 2.2-fold stronger mean fluorescence intensity in tumor tissue than the unmodified liposomes at 24 hours. In summary, GE11-modified liposomes may be a promising platform for targeted delivery of chemotherapeutic drugs in NSCLC.

A dual-mediated liposomal drug delivery system targeting the brain: rational construction, integrity evaluation across the blood–brain barrier, and the transporting mechanism to glioma cells

“…23 TF 3.4K -SSL with 0, 0.25%, 0.5%, 1.5%, 1.8%, and 2% of TF densities were each prepared by regulating the molar ratio of SPC/cholesterol/DSPE-PEG 3.4K -MAL/DSPE-PEG 2K / TF-SH =100:50:4n:(8-4n):n (n=0, 0.25, 0.5, 1.5, 1.8, 2.0). The cellular uptakes of TF 3.4K -SSL (coumarin-6) with different TF densities were investigated on BMVECs by FCM.…”

Preparation and evaluation of peptide-dendrimer-paclitaxel conjugates for treatment of heterogeneous stage 1 nonsmall cell lung cancer in 293T and L132 cell lines

“…The solution was stirred overnight on magnetic stirrer and the crude product was dialyzed using dialysis membrane (molecular weight cut off = 3500 Da).Removal of peptide was ensured by measuring absorbance at 280 nm. The product obtained was lyophilized in a dark room for 24 h to yield free-flowing powder of peptidedendrimer-paclitaxel conjugates [13].…”

“…Conjugation efficiency (CE) of the PTX from PAMAM-PTX and GE-PAMAM-PTX were calculated as in Eq 1 [13]. % C.E = {(Td -Fd)/Td}100 ……………….…”

“…Thereafter, 1 mg/mL MTT was added and incubated for 1 h with the treated human lung cancer cell line 293T at 37 o C. Amount of MTT converted to insoluble formazan dye by mitochondrial dehydrogenases determines the viable cells. The formed formazan crystals were dissolved in a 1 M HClisopropyl alcohol mixture (1:24 v/v) and shaken for 20 min at room temperature [13].…”

“…Liu et al successfully developed peptide dendrimer conjugates as drug carriers for NSCLC [12]. Also Cheng et al developed GEII modified liposomes for NSCLC targeting [13]. Apart from this, Long et al have developed doxorubicin encapsulated EGF surface modified gelatin nanoparticles to target EGFR overexpressed in lung cancer tissue [14].…”