Theranostics最新文献

[This corrects the article DOI: 10.7150/thno.22557.].

Background: Local immunomodulation with nanoparticles (NPs) and focused ultrasound (FUS) is recognized for triggering anti-tumor immunity. However, the impact of these tumor immunomodulations on sex-specific microbiome diversity at distant sites and their correlation with therapeutic effectiveness remains unknown. Here, we conducted local intratumoral therapy using immunogenic cell death-enhancing Calreticulin-Nanoparticles (CRT-NPs) and FUS in male and female mice. We identified immune-related microbiome populations, aiming to translate our findings into clinical applications. Methods: CRT-NPs were synthesized by loading CRT-delivering plasmids into cationic liposomes. Local tumor therapy was performed using CRT-NP and FUS-based histotripsy (HT) on poorly immunogenic Mouse Oral Squamous Cell Carcinoma (MOC2) in the flank regions of male and female mice. Fecal samples were collected and analyzed before and three weeks post-treatment. The microbiome features were then correlated with immune cell dynamics within tumors and systemic cytokine responses to identify prognostic biomarkers in both male and female subjects. Results: Intratumorally administered CRT-NP induced tumor remission and immune cell activation in both male and female mice, whereas HT was ineffective in males and showed efficacy only in females. Turicibacter and Peptococcus inversely correlated with tumor growth, while Enterorhabdus, Subdologranulum, Desulfovibrio, and Aldercreutzia-Asaccharobacter showed direct correlations with tumor growth. HT induced higher levels of Turicibacter in MOC2-bearing females, while males displayed increased Enterorhabdus and Streptococcus populations. Independent of sex, treatments promoting CD4+ T helper cells, functional CD8+ T cells, and total macrophage infiltration correlated with higher levels of Gastrophilales, Romboutsia, Turicibacter, and Peptococcus. Alternatively, Enterorhabdus, Desulfovibrio, Streptococcus, and Staphylococcus corresponded to poor treatment outcomes in both sexes. Conclusion: An enhanced abundance of Enterorhabdus, Desulfovibrio, Streptococcus, and Staphylococcus in response to immunomodulatory therapies could serve as predictive biomarkers in a sex-independent manner. These findings could also be potentially extended to the realm of personalized interventions through fecal transplantations to reverse immunosuppressive phenotypes in males and improve patient outcomes.

Rationale: Tumor-associated macrophages (TAMs) are abundant in colorectal cancer (CRC), correlating with immunosuppression and disease progression. Activation of the stimulator of interferon gene (STING) signaling pathway in TAMs offers a promising approach for CRC therapy. However, current STING agonists face challenges related to tumor specificity and administration routes. Method: The Cancer Genome Atlas (TCGA) database analysis and multicolor immunofluorescence experiments of human CRC samples analysed triggering receptor expressed on myeloid cells 2 (TREM2) expression in the tumor microenvironment of CRC patients. We designed and synthesized a STING agonist prodrug GB2 to reprogram TAMs by targeting TREM2 in tumors. Preliminary evaluation of the anti-tumor capacity of prodrug GB2 in the mouse CRC model intravenously. RNA-seq analysis of bone marrow-derived macrophages (BMDM) after GB2 treatment reveals novel pharmacological mechanisms for the prodrug GB2. Results: Over-expressed TREM2 in TAMs correlates with CRC progression. Via targeting TREM2 expressed in TAMs, GB2 induces comprehensive tumor regression by administrating intravenously in mouse colon cancer models, as well as in a STING^low mouse melanoma model, with no systemic toxicity. Upon treatment with GB2, TAMs exhibit an M1 phenotype with pro-inflammatory function and demonstrate enhanced phagocytosis capacity. The molecular mechanisms involve (1) GB2 upregulating the Glycolysis-ROS-HIF-1α axis, thereby promoting glucose metabolism and inflammatory cytokine expression; (2) GB2 inducing endoplasmic reticulum-mitochondria contact (MERC), leading to mitochondrial fission, ultimately facilitating Ca²⁺-mediated phagocytosis. Besides, GB2-treated macrophages reverse immunosuppression, facilitating CD8⁺ T cell tumor infiltration and effector function. Combining GB2 with αPD-1 therapy reveals a synergistic effect on tumor inhibition, leading to prolonged mouse survival. Conclusion: By targeting TREM2 and activating the STING signaling pathway in TAMs, prodrug GB2 exhibits excellent anti-tumor efficacy and immune-activating capacity in the mouse colon cancer model.

Rationale: Cardiac fibroblasts are activated following myocardial infarction (MI) and cardiac fibrosis is a major driver of the growing burden of heart failure. A non-invasive targeting method for activated cardiac fibroblasts would be advantageous because of their importance for imaging and therapy. Methods: Targeting was achieved by linking a 7-amino acid peptide (EP9) to a perfluorocarbon-containing nanoemulsion (PFC-NE) for visualization by ¹⁹F-combined with ¹H-MRI. In vivo and ex vivo ¹H/¹⁹F MRI was performed on a Bruker 9.4 T AVANCE III wide-bore nuclear magnetic resonance spectrometer. Photoaffinity labeling (diazirine photolinker) and mass spectrometry were used to identify the peptide-binding protein. Molecular modeling studies used ColabFold and AlphaFold 3. EP9-decorated liposomes containing modified mRNA for luciferase (mRNA-LUC) were used for the study of the cellular uptake process. Results: After injection of EP9-PFC-NE, the in-vivo ¹⁹F signal localized to the infarcted area of the heart and was EP9-specific, as verified by the use of a mutated peptide. The plasma half-life of the nanoemulsion was 20 h and electron microscopy identified cardiac fibroblasts and epicardial stromal cells to be the main populations for cellular uptake. Photoaffinity labeling identified the tetraspanin CD63 as the main EP9-binding protein, which was supported by CD63-EP9 modeling data. Expression of CD63 was significantly upregulated in infarct-activated fibroblasts of mice and humans. Cellular uptake may involve caveolae and/or clathrin-coated pits as suggested by scRNAseq data. Uptake studies with mRNA-LUC-loaded EP9-PFC-NE confirmed internalization after binding to fibroblast CD63. Conclusions: CD63 was identified to contain a specific EP9 binding motive that triggers endocytosis of EP9-PFC-NE in activated cardiac fibroblasts. This targeted nanoemulsion can therefore be used for in vivo imaging and has the potential for fibroblast-specific drug delivery.

T cell receptor-engineered T (TCR-T) cell therapies are at the forefront of cancer immunotherapy, offering a transformative approach that significantly enhances the ability of T cells to recognize and eliminate cancer cells. This innovative method involves genetically modifying TCRs to increase their affinity for tumor-specific antigens. While these enhancements improve the ability of T cells to recognize and bind to antigens on cancer cells, rigorous assessment of specificity remains crucial to ensure safety and targeted responses. This dual focus on affinity and specificity holds significant promise for the treatment of solid tumors, enabling precise and efficient cancer cell recognition. Despite rapid advancements in TCR engineering and notable progress in TCR screening technologies, as evidenced by the growing number of specific TCRs entering clinical trials, several technical and clinical challenges remain. These challenges primarily pertain to the specificity, affinity, and safety of engineered TCRs. Moreover, the accurate identification and selection of TCRs that are both effective and safe are essential for the success of TCR-T cell therapies in cancer treatment. This review provides a comprehensive examination of the theoretical foundations of TCR therapy, explores strategies for screening specific TCRs and antigens, and highlights the ongoing challenges in this evolving therapeutic landscape.

Background: Disrupted hippocampal functions and progressive neuronal loss represent significant challenges in the treatment of Alzheimer's disease (AD). How to achieve the improvement of pathological progression and effective neural regeneration to ameliorate the intracerebral dysfunctional environment and cognitive impairment is the goal of the current AD therapy. Methods: We examined the therapeutic potential of clinical-grade human derived dental pulp stem cells (hDPSCs) in cognitive function and neuropathology in AD. Specifically, we investigated the effect of neural crest-specific derived hDPSCs on endogenous neural regeneration and long-term efficacy following a single transplantation in the triple-transgenic mouse model (3xTg-AD). Results: Our research demonstrated that a single administration of clinical-grade hDPSCs yielded dramatic short-term therapeutic benefits (5 weeks) and sustained partial efficacy (6 months) with respect to improving cognitive impairment and delaying typical pathological progression in 3xTg-AD mice. Intriguingly, exogenous hDPSCs were robustly self-differentiated into newborn functional neurons in the hippocampus of 3xTg-AD mice. The foremost evidence is provided that hDPSCs promote endogenic neural regeneration by enhancing the activation of the Wnt/β-catenin pathway, which may contribute to stabilizing the hippocampal neural network to reverse memory deficits. Conclusion: These findings highlight the multifunctional potential of hDPSCs in AD treatment, which enhances cognition through alleviating neuropathology and providing neural regenerative driving force. Understanding these multiplicity effects is critical to advancing the clinical translation of stem cell-based therapies for AD.

Background: Ultrasound-induced thermal strain imaging (US-TSI) is a promising ultrasound imaging modality that has been demonstrated in preclinical studies to identify a lipid-rich necrotic core of an atherosclerotic plaque. However, human physiological motion, e.g., cardiac pulsation, poses challenges in implementing US-TSI applications, where achieving a millisecond-level temperature rise by delivering acoustic energy from a compact US-TSI probe is a key requirement. This study aims to develop a transient ultrasound heating and thermocouple monitoring technique at the millisecond level for US-TSI applications. Methods: We designed, prototyped, and characterized a novel US-TSI probe that includes a high-power, 3.5 MHz heating transducer with symmetrical dual 1D concave array. Additionally, millisecond-level temperature monitoring was demonstrated with fast-response thermocouples in laser- and ultrasound- induced thermal tests. Subsequently, we demonstrated the prototyped US-TSI probe can produce a desired temperature rise in a millisecond-short time window in vitro phantom and in vivo animal tests. Results: The prototyped US-TSI probe delivered zero-to-peak acoustic pressure up to 6.2 MPa with a 90 V_PP input voltage. Both laser- and ultrasound- induced thermal tests verified that the selected thermocouples can monitor temperature change within 50 ms. The fast-response thermocouple confirmed the transient heating ability of the US-TSI probe, achieving a 3.9 °C temperature rise after a 25 ms heating duration (50% duty cycle) in the gel phantom and a 2.0 °C temperature rise after a 50 ms heating duration (50% duty cycle) in a pig model. Conclusions: We successfully demonstrated a millisecond-level transient heating and temperature monitoring technique utilizing the novel US-TSI probe and fast-response thermocouples. The reported transient ultrasound heating and thermocouple monitoring technique is promising for future in vivo human subject studies in US-TSI or other ultrasound-related thermal investigations.

The tumor microenvironment (TME) is involved in cancer initiation and progression. With advances in the TME field, numerous therapeutic approaches, such as antiangiogenic treatment and immune checkpoint inhibitors, have been inspired and developed. Nevertheless, the sophisticated regulatory effects on the biological balance of the TME remain unclear. Decoding the pathological features of the TME is urgently needed to understand the tumor ecosystem and develop novel antitumor treatments. Protein serine/threonine phosphatases (PSPs) are responsible for inverse protein phosphorylation processes. Aberrant expression and dysfunction of PSPs disturb cellular homeostasis, reprogram metabolic processes and reshape the immune landscape, thereby contributing to cancer progression. Some therapeutic implications, such as the use of PSPs as targets, have drawn the attention of researchers and clinicians. To date, the effects of PSP inhibitors are less satisfactory in real-world practice. With breakthroughs in sequencing technologies, scientists can decipher TME investigations via multiomics and higher resolution. These benefits provide an opportunity to explore the TME in a more comprehensive manner and inspire more findings concerning PSPs in the TME. The current review starts by introducing the canonical knowledge of PSPs, including their members, structures and posttranslational modifications for activities. We then summarize the functions of PSPs in regulating cellular homeostasis. In particular, we specified the up-to-date roles of PSPs in modulating the immune microenvironment, adopting hypoxia, reprogramming metabolic processes, and responding to extracellular matrix remodeling. Finally, we introduce preclinical PSP inhibitors with translational value and conclude with clinical trials of PSP inhibitors for cancer treatment.

Background: Photodynamic therapy (PDT) has gained widespread attention in cancer treatment, but it still faces clinical problems such as skin phototoxicity. Activatable photosensitizers offer a promising approach to addressing this issue. However, several significant hurdles need to be overcome, including developing effective activation strategies and achieving the optimal balance between photodynamic effects and related side effects. Herein, we present a novel and general strategy for the construction of tumor-targeted activatable nanophotosensitizers (TNP1/PSs). Methods: TNP1/PSs were constructed through simple nanoprecipitation method, leveraging the strong cation-π interaction between cationic polymers and aromatic photosensitizers. We conducted a comprehensive characterization and investigation of the photoactivity, as well as the mechanisms underlying both OFF state and switched-on properties of TNP1/PSs. Additionally, we thoroughly evaluated the cytotoxicity, tumor-targeted ability, and anti-tumor efficacy of TNP1/PSs in the 4T1 cell line. Results: TNP1/PSs exhibit a markedly fully OFF state of photoactivity, subsequent to self-assembly through cation-π interactions in aqueous media. The mechanism study reveals a multi-pathway process induced by cation-π complexes, which includes reduced absorption and radiative decay, as well as enhanced thermal decay and intermolecular charge transfer. Upon targeting tumor cells, TNP1/PSs were effectively endocytosed and predominantly traversed the lysosomes, where degradation of the cationic polymer occurs, resulting in the spontaneous switch-on of PDT activity. In vivo studies employing small animal models demonstrated that the as-synthesized nanophotosensitizer possesses remarkable anti-tumor activity while completely avoiding skin phototoxicity. Conclusion: This work provides a powerful platform for efficiently constructing tumor-targeted activatable nanophotosensitizers, paving the way for safe and effective photodynamic therapy in cancer treatment.

[This corrects the article DOI: 10.7150/thno.32479.].