Galactoxyloglucan-doxorubicin nanoparticles exerts superior cytotoxic effects on cancer cells⿿A mechanistic and in silico approach

Engineering magnetotactic bacteria MVs to synergize chemotherapy, ferroptosis and immunotherapy for augmented antitumor therapy

One main obstacle to targeted cancer therapies is the immunosuppressive tumor microenvironment, which can facilitate tumor growth and induce resistance to antitumor treatments. Recent studies have indicated that treatment combined with immunotherapy often yields a better prognosis than monotherapy. Bacterial membrane vesicles (MVs), nanostructures released from the membrane of bacteria, can be used as natural nanocarriers for drug delivery and stimulate an immune response because of their immunogenicity. Inspired by the development of synergistic therapeutic strategies, we herein propose a novel nanovaccine-based platform to achieve chemotherapy, ferroptosis therapy, and immunotherapy simultaneously. By simply culturing magnetotactic bacteria in the medium with doxorubicin (DOX) and then extracting specialized MVs (BMVs), BMV@DOX, which are membrane vesicles containing iron ions and DOX, were obtained. We confirmed that in BMV@DOX, the BMV component can stimulate the innate immune system, DOX acts as the chemotherapeutic agent and iron ions will induce ferroptosis. Furthermore, BMV@DOX vesicles modified with DSPE-PEG-cRGD peptides (T-BMV@DOX) have minimized systemic toxicity and increased tumor-specificity. We demonstrated that the smart MVs-based nanovaccine system not only showed superior performance in the treatment of 4T1 breast cancer but also effectively restrained the growth of drug-resistant MCF-7/ADR tumors in mice. Moreover, the nanovaccine could abrogate in vivo lung metastasis of tumor cells in a 4T1-Luc cell induced-lung breast cancer metastasis model. Collectively, the MVs-based nanoplatform offers an alternative promise for surmounting the limitations of monotherapy and may deserve further study for application in synergistic cancer therapy.

The inhibitory effect of anti- tumor polysaccharide from Punica granatum on metastasis

Galactomannan (PSP001) isolated from the fruit rind of Punica granatum was demonstrated as an excellent antioxidant, immunomodulatory and anticancer agent both in vitro and in vivo models. Since the most lethal and debilitating attribute of cancer cells is their ability to evolve to a state of malignancy, with key features like increased angiogenesis, invasion, migration, colony formation, and metastasis, the present study focused on evaluating the effects of the galactomannan on tumor and malignancy. PSP001 effectively reduced the neovascularization in chick embryos highlighting its potential as an angiogenic inhibitor. Furthermore, the invasion, migration and clonogenic capacity of human and murine cancer cells were dramatically inhibited by PSP001. Evaluation of the molecular mechanism of its unique potential revealed the down regulation of key players including VEGF, MMP-2, and MMP-9 with marked elevation of TIMP-1 and TIMP-2. The anti-metastatic potential of PSP001 tested in pulmonary metastasis C57BL/6 mice model deciphered the combinatorial administration with vincristine deliberated better survival rates and decreased metastatic index. The angiogenic inhibition potential of PSP001 was further proved with peritoneal angiogenesis assay in BALB/c mice ascitic tumor model. The outcomes of the current investigation highlight the mode of action of antitumor galactomannan in the reduction of tumor malignancy.