Targeted Delivery of Combination Therapeutics Using Monoclonal Antibody 2C5-Modified Immunoliposomes for Cancer Therapy.

PURPOSE: To develop immunoliposomes modified with monoclonal cancer-specific antibody (mAb) 2C5 and co-loaded with a combination of two chemotherapeutics, in order to simultaneously target bulk cancer cells using paclitaxel and cancer stem cells (CSCs) using salinomycin to prevent cancer growth and metastases. METHODS: Breast cancer cells (MDA-MB-231 and/or SK-BR-3) were chosen as models for all in vitro testing. Liposomes composed of natural phospholipids co-loaded with salinomycin and paclitaxel were prepared and physically characterized. Immunoliposomes modified with mAb 2C5 coupled to polymeric conjugate were prepared and characterized for specific targeting. Wound healing assay was performed using the combination of free drugs in vitro. In vitro studies on cellular interaction and uptake were followed by holographic imaging to study cell-killing, cell-division and proliferation inhibiting effects of the formulation. Ex-vivo study on hemolysis was investigated to check possible toxicity of the formulation. RESULTS: Physical characterization of the liposomes showed stable nanoparticles of consistent and desirable size range (170-220 nm), zeta potential (-13 mV to - 20 mV), polydispersity indices (<0.2) and drug encapsulation efficiencies (~150 µg per ml for salinomycin, ~210 µg/ml for paclitaxel and 1:1 for combination drug loaded liposomes). Combination therapy strongly affected cancer cell proliferation as shown by significant diminishing of artificial gap closure at the wound site on MDA-MB-231 cells in culture using wound healing assay. Quantitation of changes in wound widths showed ~219 µm for drug combination, ~104 µm for only paclitaxel, and ~ 7 µm for only salinomycin treatments. Statistically significant increase in cellular interaction and specific uptake of the targeted drug co-loaded liposomal nanopreparation (p value ≤ 0.05) by MDA-MB-231 and SK-BR-3 cells confirmed the effectiveness of the approach. Holographic imaging using MDA-MB-231 cells produced visible increase in cell-killing, proliferation and division in vitro. Ex-vivo experimentation showed reduced hemolysis correlating with low toxicity in athymic nude mice model. CONCLUSION: The results demonstrated the enhanced therapeutic efficacy of a combination of salinomycin and paclitaxel delivered by mAb 2C5-modified liposomal preparation in cancer therapy.

Development, Characterization and Pharmacological Evaluation of Antiblemish Cream Containing Herbal Oils.

BACKGROUND: Many topical agents are available in the market, which interfere with the pigmentation process at different levels. They are often known to cause side effects ranging from irritation to tumor over chronic use. OBJECTIVE: The present study was designed to develop and characterize an anti blemish cream containing herbal oils. METHODS: A herbal cream was formulated using dill, nagarmotha and black cumin oil and subjected to evaluation of its anti blemish potential against stress augmented UV-B rays-induced hyperpigmentation. Topical oil in water type of creams containing 2%, 4% and 6% of each oil was formulated using herbal oils. The formulated cream was characterized for solubility, pH, particle size, grittiness, viscosity, stability, phase separation, shelf life and spreadability, and found to be stable. Acute dermal toxicity was carried out individually for dill, nagarmotha and black cumin oil according to the OECD guidelines 402. Hyperpigmentation was induced in all the experimental animals by stress-augmented UV-B irradiation method. The animals were treated for 30 days (twice daily) with standard and test formulations by topical administration, whereas the disease group was left untreated. The skin of the animals was subjected to photographical study as well as grading for pigmentation and irritation before and after treatment. After the treatment period, the serum antioxidant levels were estimated and histopathology, histochemical studies of skin were performed. RESULTS: The animals treated with test formulations containing 2%, 4%, and 6% of herbal oil showed significant improvement in pigmentation compared to disease control as it is evident in photographic biochemical, histopathological and histochemical studies. CONCLUSION: Thus, it was concluded that the developed anti-blemish cream containing herbal oils possesses significant anti-blemish potential. This study necessitates further evaluations in human subjects as it could have a high positive therapeutic value in the treatment of hyperpigmentation.

Hydrogels and Their Applications in Targeted Drug Delivery.

Conventional drug delivery approaches are plagued by issues pertaining to systemic toxicity and repeated dosing. Hydrogels offer convenient drug delivery vehicles to ensure these disadvantages are minimized and the therapeutic benefits from the drug are optimized. With exquisitely tunable physical properties that confer them great controlled drug release features and the merits they offer for labile drug protection from degradation, hydrogels emerge as very efficient drug delivery systems. The versatility and diversity of the hydrogels extend their applications beyond targeted drug delivery also to wound dressings, contact lenses and tissue engineering to name but a few. They are 90% water, and highly porous to accommodate drugs for delivery and facilitate controlled release. Herein we discuss hydrogels and how they could be manipulated for targeted drug delivery applications. Suitable examples from the literature are provided that support the recent advancements of hydrogels in targeted drug delivery in diverse disease areas and how they could be suitably modified in very different ways for achieving significant impact in targeted drug delivery. With their enormous amenability to modification, hydrogels serve as promising delivery vehicles of therapeutic molecules in several disease conditions, including cancer and diabetes.

Phage-derived protein-mediated targeted chemotherapy of pancreatic cancer.

Pancreatic cancer has been a life-threatening illness associated with high incidence and mortality rates. Paclitaxel (PCT) that causes mitotic arrest in cancer cells disrupting microtubule function is used for pancreatic cancer treatment. Nausea, anorexia and abdominal pain are some of the typical dose-limiting toxicity associated gastrointestinal side effects of the drug. Here, we present the use of polymeric mixed micelles to enable a targeted delivery of PCT and to provide additional advantages such as enhanced drug solubility, bioavailability and minimal dose-limiting toxicity. Also, these micelles self-assemble with pancreatic cancer cells-specific phage proteins P38, L1 and with the hydrophobic drug PCT resolving the issue of complex chemistry efforts normally needed for any conjugation. Our cytotoxicity and binding experiment results in vitro in 2 D and 3 D models suggested that the phage protein-targeted drug-loaded micelles bind and exhibit higher cell killing over the non-targeted ones.

Combination therapy targeting both cancer stem-like cells and bulk tumor cells for improved efficacy of breast cancer treatment.

Many types of tumors are organized in a hierarchy of heterogeneous cell populations. The cancer stem-like cells (CSCs) hypothesis suggests that tumor development and metastasis are driven by a minority population of cells, which are responsible for tumor initiation, growth and recurrences. The inability to efficiently eliminate CSCs during chemotherapy, together with CSCs being highly tumorigenic and invasive, may result in treatment failure due to cancer relapse and metastases. CSCs are emerging as a promising target for the development of translational cancer therapies. Ideal panacea for cancer would kill all malignant cells, including CSCs and bulk tumor cells. Since both chemotherapy and CSCs-specific therapy are insufficient to cure cancer, we propose combination therapy with CSCs-targeted agents and chemotherapeutics for improved breast cancer treatment. We generated in vitro mammosphere of 2 breast cancer cell lines, and demonstrated ability of mammospheres to grow and enrich cancer cells with stem-like properties, including self-renewal, multilineage differentiation and enrichment of cells expressing breast cancer stem-like cell biomarkers CD44(+)/CD24(-/low). The formation of mammospheres was significantly inhibited by salinomycin, validating its pharmacological role against the cancer stem-like cells. In contrast, paclitaxel showed a minimal effect on the proliferation and growth of breast cancer stem-like cells. While combination therapies of salinomycin with conventional chemotherapy (paclitaxel or lipodox) showed a potential to improve tumor cell killing, different subtypes of breast cancer cells showed different patterns in response to the combination therapies. While optimization of combination therapy is warranted, the design of combination therapy should consider phenotypic attributes of breast cancer types.

Improving Peptide Applications Using Nanotechnology.

Peptides are being successfully used in various fields including therapy and drug delivery. With advancement in nanotechnology and targeted delivery carrier systems, suitable modification of peptides has enabled achievement of many desirable goals over-riding some of the major disadvantages associated with the delivery of peptides in vivo. Conjugation or physical encapsulation of peptides to various nanocarriers, such as liposomes, micelles and solid-lipid nanoparticles, has improved their in vivo performance multi-fold. The amenability of peptides to modification in chemistry and functionalization with suitable nanocarriers are very relevant aspects in their use and have led to the use of 'smart' nanoparticles with suitable linker chemistries that favor peptide targeting or release at the desired sites, minimizing off-target effects. This review focuses on how nanotechnology has been used to improve the number of peptide applications. The paper also focuses on the chemistry behind peptide conjugation to nanocarriers, the commonly employed linker chemistries and the several improvements that have already been achieved in the areas of peptide use with the help of nanotechnology.