A biocompatible glycol-capped nano-delivery system with stimuli-responsive drug release kinetics abrogates cancer cell survival

HER2 siRNA Facilitated Gene Silencing Coupled with Doxorubicin Delivery: A Dual Responsive Nanoplatform Abrogates Breast Cancer

The present study investigated the concurrent delivery of antineoplastic drug, doxorubicin, and HER2 siRNA through a targeted theranostic metallic gold nanoparticle designed using polysaccharide, PSP001. The as-synthesized HsiRNA@PGD NPs were characterized in terms of structural, functional, physicochemical, and biological properties. HsiRNA@PGD NPs exposed adequate hydrodynamic size, considerable ζ potential, and excellent drug/siRNA loading and encapsulation efficiency. Meticulous exploration of the biocompatible dual-targeted nanoconjugate exhibited an appealing biocompatibility and pH-sensitive cargo release kinetics, indicating its safety for use in clinics. HsiRNA@PGD NPs deciphered competent cancer cell internalization, enhanced cytotoxicity mediated via the induction of apoptosis, and excellent downregulation of the overexpressing target HER2 gene. Further in vivo explorations in the SKBR3 xenograft breast tumor model revealed the appealing tumor reduction properties, selective accumulation in the tumor site followed by significant suppression of the HER2 gene which contributed to the exclusive abrogation of breast tumor mass by the HsiRNA@PGD NPs. Compared to free drugs or the monotherapy constructs, the dual delivery approach produced a synergistic suppression of breast tumors both in vitro and in vivo. Hence the drawings from these findings implicate that the as-synthesized HsiRNA@PGD NPs could offer a promising platform for chemo-RNAi combinational breast cancer therapy.

Galactomannan armed superparamagnetic iron oxide nanoparticles as a folate receptor targeted multi-functional theranostic agent in the management of cancer

Superparamagnetic iron oxide nanoparticles (SPIONs) represent a versatile class of theranostics with profound applications in biomedicine. An eco-friendly modification of SPIONs was attempted with a 110 kDa galactomannan (PSP001) isolated from the fruit rind of Punica granatum. The PSP001 appended SPIONs favor unique advantages including tumor-targeted accumulation and improved biocompatibility. The antineoplastic agent methotrexate (MTX) was covalently attached with the galactomannan in the SPIONs to yield PSP-IO NPs that demonstrated a reduction-sensitive drug release kinetics favoring MTX accumulation selectively in the tumor cells. Folate receptor (FR) targeted cancer cell uptake followed by the stimuli-responsive release of the payload favored improved biocompatibility and lack of toxicity in BALB/c mice. Superior tumor reduction capacity with marked survival benefits was observed in Ehrlich ascites carcinoma (EAC) bearing solid tumor mice. Phantom imaging of the carrier (PSP-IO) and the drug-loaded (PSP-IO-MTX NPs) nano-constructs generated an r2 relaxivity of 335.3 mM^-1 S^-1 and 333.79 mM^-1 S^-1 respectively indicating the remarkable contrast in magnetic resonance imaging (MRI) which was confirmed in syngraft and xenograft murine models. It is worth mentioning that PSP-IO-MTX NPs with a facile fabrication process offered an affordable nano-theranostic agent for targeted concurrent MR imaging and FR-mediated targeted tumor therapy favoring bed-side applications.

Advances in plant-derived natural products for antitumor immunotherapy

In recent years, immunotherapy has emerged as a novel antitumor strategy in addition to traditional surgery, radiotherapy and chemotherapy. It uniquely focuses on immune cells and immunomodulators in the tumor microenvironment and helps eliminate tumors at the root by rebuilding the immune system. Despite remarkable breakthroughs, cancer immunotherapy still faces many challenges: lack of predictable and prognostic biomarkers, adverse side effects, acquired treatment resistance, high costs, etc. Therefore, more efficacious and efficient, safer and cheaper antitumor immunomodulatory drugs have become an urgent requirement. For decades, plant-derived natural products obtained from land and sea have provided the most important source for the development of antitumor drugs. Currently, more attention is being paid to the discovery of potential cancer immunotherapy modulators from plant-derived natural products, such as polysaccharides, phenols, terpenoids, quinones and alkaloids. Some of these agents have outstanding advantages of multitargeting and low side effects and low cost compared to conventional immunotherapeutic agents. We intend to summarize the progress of comprehensive research on these plant-derived natural products and their derivatives and discuss their possible mechanisms in regulating the immune system and their efficacy as monotherapies or in combination with regular chemotherapeutic agents.