Normalizing Tumor Blood Vessels to Improve Chemotherapy and Inhibit Breast Cancer Metastasis by Multifunctional Nanoparticles

Research progress of nano drug delivery systems in the anti-tumor treatment of traditional Chinese medicine monomers

Tumors pose a serious threat to global public health and are usually treated from two aspects: tumor cells and tumor microenvironment. Compared with traditional chemotherapy drugs, traditional Chinese medicine (TCM) monomers have advantages in tumor treatment, such as multiple targets, multiple levels and synergistic intervention. However, most TCM active ingredients have disadvantages such as poor water solubility and stability, which restrict their clinical application. Nano drug delivery systems have the functions of improving the bioavailability of TCM anti-tumor active ingredients, enhancing tissue targeting, achieving controlled drug release, and inhibiting tumor multidrug resistance. Compared with free monomers, they have higher therapeutic effects and fewer side effects. This article summarizes five commonly used anti-tumor TCM monomer nanocarriers, including lipid nanomaterials, exosomes, polymer micelles, carbon nanotubes, and dendrimers, and explains their anti-tumor mechanisms after combining with TCM, such as inhibiting tumor cell proliferation and metastasis, regulating tumor microenvironment, etc. At the same time, the potential of nano drug delivery systems combined with radiotherapy and immunotherapy is discussed, as well as the current problems of potential toxicity, long-term stability, and complex amplification process, as well as future development directions, aiming to provide a reference for promoting the clinical application of nano drug delivery systems for TCM anti-tumor active ingredients.

Navigating Tumor Microenvironment Barriers with Nanotherapeutic Strategies for Targeting Metastasis

Therapeutic strategy for efficiently targeting cancer cells needs an in-depth understanding of the cellular and molecular interplay in the tumor microenvironment (TME). TME comprises heterogeneous cells clustered together to translate tumor initiation, migration, and proliferation. The TME mainly comprises proliferating tumor cells, stromal cells, blood vessels, lymphatic vessels, cancer-associated fibroblasts (CAFs), extracellular matrix (ECM), and cancer stem cells (CSC). The heterogeneity and genetic evolution of metastatic tumors can substantially impact the clinical effectiveness of therapeutic agents. Therefore, the therapeutic strategy shall target TME of all metastatic stages. Since the advent of nanotechnology, smart drug delivery strategies are employed to deliver effective drug formulations directly into tumors, ensuring controlled and sustained therapeutic efficacy. The state-of-the-art nano-drug delivery systems are shown to have innocuous modes of action in targeting the metastatic players of TME. Therefore, this review provides insight into the mechanism of cancer metastasis involving invasion, intravasation, systemic transport of circulating tumor cells (CTCs), extravasation, metastatic colonization, and angiogenesis. Further, the novel perspectives associated with current nanotherapeutic strategies are highlighted on different stages of metastasis.

Nomogram for predicting post-progression-free survival in patients with recurrent pancreatic ductal adenocarcinoma after radical surgery: a retrospective analysis

BACKGROUND

Radical resection is the only curative method for patients with pancreatic adenocarcinoma (PDAC). However, nearly 85% of PDAC patients suffer from local or distant recurrence within 5 years after curative resection. The progression of recurrent lesions accelerates the mortality rate in PDAC patients. However, the influence of clinicopathological factors on post-progression-free survival (PPFS), defined as the period from tumor recurrence to the timing of the progression of recurrent lesions, has rarely been discussed. The present study aimed to explore the independent prognostic factors for PPFS and construct a nomogram for PPFS prediction.

MATERIALS AND METHODS

The 200 recurrent PDAC patients were divided into training and validation groups by leave-one-out cross-validation. The patients' clinicopathological characteristics were compared through a chi-square test. Meanwhile, these factors were enrolled in the univariate and multivariate COX regression to find the independent prognostic factors of PPFS. Moreover, the Kaplan-Meier survival analysis based on the independent prognostic factors was performed. Finally, we constructed a nomogram model for PPFS prediction, followed by an effectiveness examination.

RESULTS

PDAC patients who received multi-agent chemotherapy after surgery showed a longer PPFS than the single-agent chemotherapy group. PDAC patients who received multi-agent chemotherapy after recurrence showed a similar PPFS compared to the single-agent chemotherapy group. Local recurrence with distant metastases, early recurrence, lympho-vascular invasion, higher T stage, and higher N stage predicted shorter PPFS in recurrent PDAC patients. Finally, a nomogram to indicate the progression of recurrent lesions was constructed.

CONCLUSION

Multi-agent chemotherapy is recommended for PDAC patients after surgery. Meanwhile, single-agent chemotherapy also deserves consideration after tumor recurrence. Moreover, the nomogram could be used in PPFS prediction.

The potential of vascular normalization for sensitization to radiotherapy

Radiotherapy causes apoptosis mainly through direct or indirect damage to DNA via ionizing radiation, leading to DNA strand breaks. However, the efficacy of radiotherapy is attenuated in malignant tumor microenvironment (TME), such as hypoxia. Tumor vasculature, due to the imbalance of various angiogenic and anti-angiogenic factors, leads to irregular morphology of tumor neovasculature, disordered arrangement of endothelial cells, and too little peripheral coverage. This ultimately leads to a TME characterized by hypoxia, low pH and high interstitial pressure. This deleterious TME further exacerbates the adverse effects of tumor neovascularization and weakens the efficacy of conventional radiotherapy. Whereas normalization of blood vessels improves TME and thus the efficacy of radiotherapy. In addition to describing the research progress of radiotherapy sensitization and vascular normalization, this review focuses on the strategy and application prospect of modulating vascular normalization to improve the efficacy of radiotherapy sensitization.

Tumor Cell Lysate-Based Multifunctional Nanoparticles Facilitate Enhanced mRNA Delivery and Immune Stimulation for Melanoma Gene Therapy

Messenger ribonucleic acid (mRNA)-based gene therapy has great potential for cancer gene therapy. However, the effectiveness of mRNA in cancer therapy needs to be further improved, and the delivery efficiency and instability of mRNA limit the application of mRNA-based products. Both the delivery efficiency can be elevated by cell-penetrating peptide modification, and the immune response can be enhanced by tumor cell lysate stimulation, representing an advantageous strategy to expand the effectiveness of mRNA gene therapy. Therefore, it is vital to exploit a vector that can deliver high-efficiency mRNA with codelivery of tumor cell lysate to induce specific immune responses. We previously reported that DMP cationic nanoparticles, formed by the self-assembly of DOTAP and mPEG-PCL, can deliver different types of nucleic acids. DMP has been successfully applied in gene therapy research for various tumor types. Here, we encapsulated tumor cell lysates with DMP nanoparticles and then modified them with a fused cell-penetrating peptide (TAT-iRGD) to form an MLSV system. The MLSV system was loaded with encoded Bim mRNA, forming the MLSV/Bim complex. The average size of the synthesized MLSV was 191.4 nm, with a potential of 47.8 mV. The MLSV/mRNA complex promotes mRNA absorption through caveolin-mediated endocytosis, with a transfection rate of up to 68.6% in B16 cells. The MLSV system could also induce the maturation and activation of dendritic cells, obviously promoting the expression of CD80, CD86, and MHC-II both in vitro and in vivo. By loading the encoding Bim mRNA, the MLSV/Bim complex can inhibit cell proliferation and tumor growth, with inhibition rates of up to 87.3% in vitro. Similarly, the MLSV/Bim complex can inhibit tumor growth in vivo, with inhibition rates of up to 78.7% in the B16 subcutaneous tumor model and 63.3% in the B16 pulmonary metastatic tumor model. Our results suggest that the MLSV system is an advanced candidate for mRNA-based immunogene therapy.