Folate-Targeted Nanostructured Lipid Carriers (NLCs) Enhance (Letrozol) Efficacy in MCF-7 Breast Cancer Cells

Nanomedicine in therapeutic warfront against estrogen receptor-positive breast cancer

Breast cancer (BC) is the most frequently diagnosed malignancy in women worldwide. Almost 70-80% of cases of BC are curable at the early non-metastatic stage. BC is a heterogeneous disease with different molecular subtypes. Around 70% of breast tumors exhibit estrogen-receptor (ER) expression and endocrine therapy is used for the treatment of these patients. However, there are high chances of recurrence in the endocrine therapy regimen. Though chemotherapy and radiation therapy have substantially improved survival rates and treatment outcomes in BC patients, there is an increased possibility of the development of resistance and dose-limiting toxicities. Conventional treatment approaches often suffer from low bioavailability, adverse effects due to the non-specific action of chemotherapeutics, and low antitumor efficacy. Nanomedicine has emerged as a conspicuous strategy for delivering anticancer therapeutics in BC management. It has revolutionized the area of cancer therapy by increasing the bioavailability of the therapeutics and improving their anticancer efficacy with reduced toxicities on healthy tissues. In this article, we have highlighted various mechanisms and pathways involved in the progression of ER-positive BC. Further, different nanocarriers delivering drugs, genes, and natural therapeutic agents for surmounting BC are the spotlights of this article.

Nanostructured Lipid Carriers Engineered as Topical Delivery of Etodolac: Optimization and Cytotoxicity Studies

Etodolac (ETD), a nonsteroidal anti-inflammatory drug, exhibits antinflammatory, analgesic, and antipyretic activity. The main type of ETD administration is oral route, which is associated with significant systemic side effects. Nanostructured lipid carriers (NLC), a modern lipid formulation, are non-toxic, biocompatible, can improve the solubility and stability of drugs. Nanostructured lipid carriers (NLC) containing etodolac were prepared by a melt-emulsification and ultrasonication technique. Full factorial design (FFD) was applied to optimize the composition of NLC and their properties such as zeta potential, polidyspersity index, and entrapment efficiency. Formulations consisting of Capryol 90, glicerol monostearate, and Tween 20 displayed particle size below 300 nm, encapsulated drug with efficiency of approximately 87% and prolonged drug release up to 24 h. Stable formulations displayed moderately negative surface charge suggesting their limited ability to interact with skin surface but simultaneously presenting their lower risk to cause cell-membrane disruption. In fact, cytotoxicity assessment using human dermal fibroblasts and human epidermal keratinocytes revealed that etodolac-loaded NLC had no important impact on skin cells viability evaluated in vitro, which might evidence that NLC formulations are safe for dermal delivery. The studies developed were relatively fast and simple, requiring no specialized equipment method to prepare NLC as ETD carriers ensuring better solubility and prolonged drug release.

Nanostructured Lipid Carrier-Mediated Transdermal Delivery of Aceclofenac Hydrogel Present an Effective Therapeutic Approach for Inflammatory Diseases

Aceclofenac (ACE), a cyclooxygenase-2 inhibitor, is the derivative of the diclofenac group that has been in use for the symptomatic treatment of systemic inflammatory autoimmune disease, rheumatoid arthritis (RA). Partial solubility, high lipophilic nature, and stability challenge its use in developing topical formulations. Hence, we developed and characterized nanostructured lipid carrier (NLC)-based ACE (ACE-NLC) hydrogel for an efficient transdermal delivery. NLC microemulsion was prepared using different lipids by various methods and was characterized with respect to particle size, zeta potential, surface morphology, and drug encapsulation efficiency. The optimized NLC formulation was incorporated into Carbopol^® 940 gel, and this arrangement was characterized and compared with the existing marketed gel (Mkt-gel) formulation to assess in vitro drug release, rheology, texture profile, in vivo skin retention and permeation, and stability. Furthermore, prepared and characterized ACE-loaded NLC formulation was evaluated for skin integrity and fitted in a dermatokinetic model. The results of this study confirmed the spherical shape; smooth morphology and nanometric size attested by Zetasizer and scanning and transmission electron microcopy; and stability of the ACE-NLC formulation. The ACE-NLC-gel formulation showed good rheological and texture characteristics, and better skin distribution in the epidermis and dermis. Moreover, ACE-NLC permeated deeper in the skin layers and kept the skin integrity intact. Overall, NLC-based gel formulation of ACE might be a promising nanoscale lipid carrier for topical application when compared with the conventional Mkt-gel formulation.

Adjuvant Therapy with Silibinin Improves the Efficacy of Paclitaxel and Cisplatin in MCF-7 Breast Cancer Cells

Herbal-derived medicines have introduced as sources of novel drugs due to minimum systemic side effects. Silibinin as a flavonoid compound has showed with effective chemotherapeutic effects on different cancers. Here, we investigated the impact of combination therapy of silibinin, with paclitaxel and cisplatin in inhibition of proliferation and induction of apoptosis in MCF-7 cells. Cell proliferation was assessed by MTT assay and the percentage of apoptotic cells was measured using flowcytometric assay. Understand of molecular mechanism of this combination related to apoptotic pathway were evaluated by Real Time RT-PCR assays. The IC₅₀ values for silibinin, paclitaxel and cisplatin were 160 ± 22.2 µM, 33.7 ± 4.2 nM and 3.2 ± 0.5 µM, respectively. Paclitaxel and cisplatin induced higher percentage of apoptosis in MCF-7 (P < 0.05). Treatment of cell line with combination of silibinin and paclitaxel or cisplatin showed enhanced early apoptosis 56% and 61%, respectively (P < 0.05). Gene expression patterns demonstrated a significant decrease in anti-apoptotic Bcl-2 with increase in pro-apoptotic Bax, P53, BRCA1 and ATM mRNA levels. Taken together combination therapy of breast cancer cells by applying paclitaxel or cisplatin with silibinin synergistically increases the anti-proliferative effect of single agents.