Cathepsin K-Activated Probe for Fluoro-Photoacoustic Imaging of Early Osteolytic Metastasis.

Precise detection of early osteolytic metastases is crucial for their treatment but remains challenging in the clinic because of the limited sensitivity and specificity of traditional imaging techniques. Although fluorescence imaging offers attractive features for the diagnosis of osteolytic metastases, it is hampered by limited penetration depth. To address this issue, a fluoro-photoacoustic dual-modality imaging probe comprising a near-infrared dye caged by a cathepsin K (CTSK)-cleavable peptide sequence on one side and functionalized with osteophilic alendronate through a polyethylene glycol linker on the other side is reported. Through systematic in vitro and in vivo experiments, it is demonstrated that in response to CTSK, the probe generated both near-infrared fluorescent and photoacoustic signals from bone metastatic regions, thus offering a potential strategy for detecting deep-seated early osteolytic metastases.

Tuning the Organ Tropism of Polymersome for Spleen-Selective Nanovaccine Delivery to Boost Cancer Immunotherapy.

The past few decades have witnessed explosive development in drug delivery systems. However, in vivo delivery suffers from non-specific distribution in non-targeted organs or tissues, which may cause undesired side effects and even genotoxicity. Here, a general strategy that enables tuning the tropism of polymersomes for liver- and spleen-selective delivery is reported. By using a library screening approach, spleen-targeted polymersome PH9-Aln-8020 and liver-targeted polymersome PA9-ZP3-5050 are identified accordingly. Meanwhile, the second near-infrared (NIR-II) fluorescence imaging allows for in vivo dynamic evaluation of their spatial and temporal accumulation in specific tissues. O ur findings indicate that both polymer composition and protein corona on the surface are essential to determine the in vivo fate of polymersomes and tendency for specific organs. Importantly, PH9-Aln-8020 is employed as a systemic nanocarrier to co-deliver the antigen and adjuvant, which remarkably boost splenic immune responses in acute myeloid leukemia, melanoma, and melanoma lung metastasis mouse models. This study may open a new frontier for polymersomes in organ-selective delivery and other biomedical applications.

A Renal-Clearable Activatable Molecular Probe for Fluoro-Photacoustic and Radioactive Imaging of Cancer Biomarkers.

In vivo simultaneous visualization of multiple biomarkers is critical to accurately diagnose disease and decipher fundamental processes at a certain pathological evolution, which however is rarely exploited. Herein, a multimodal activatable imaging probe (P-125 I) is reported with activatable fluoro-photoacoustic and radioactive signal for in vivo imaging of biomarkers (i.e., hepsin and prostate-specific membrane antigen (PSMA)) associated with prostate cancer diagnosis and prognosis. P-125 I contains a near-infrared (NIR) dye that is caged with a hepsin-cleavable peptide sequence and linked with a radiolabeled PSMA-targeted ligand (PSMAL). After systemic administration, P-125 I actively targets the tumor site via specific recognition between PSMA and PSMAL moiety and in-situ generates of activated fluoro-photoacoustic signal after reacting with hepsin to release the free dye (uncaged state). P-125 I achieves precisely early detection of prostate cancer and renal clearance to alleviate toxicity issues. In addition, the accumulated radioactive and activated photoacoustic signal of probe correlates well with the respective expression level of PSMA and hepsin, which provides valuable foreseeability for cancer progression and prognosis. Thus, this study presents a multimodal activatable probe for early detection and in-depth deciphering of prostate cancer.

Fluoro-Photoacoustic Polymeric Renal Reporter for Real-Time Dual Imaging of Acute Kidney Injury.

Photoacoustic (PA) imaging agents detect disease tissues and biomarkers with increased penetration depth and enhanced spatial resolution relative to traditional optical imaging, and thus hold great promise for clinical applications. However, existing PA imaging agents often encounter the issues of slow body excretion and low-signal specificity, which compromise their capability for in vivo detection. Herein, a fluoro-photoacoustic polymeric renal reporter (FPRR) is synthesized for real-time imaging of drug-induced acute kidney injury (AKI). FPRR simultaneously turns on both near-infrared fluorescence (NIRF) and PA signals in response to an AKI biomarker (γ-glutamyl transferase) with high sensitivity and specificity. In association with its high renal clearance efficiency (78% at 24 h post-injection), FPRR can detect cisplatin-induced AKI at 24 h post-drug treatment through both real-time imaging and optical urinalysis, which is 48 h earlier than serum biomarker elevation and histological changes. More importantly, the deep-tissue penetration capability of PA imaging results in a signal-to-background ratio that is 2.3-fold higher than NIRF imaging. Thus, the study not only demonstrates the first activatable PA probe for real-time sensitive imaging of kidney function at molecular level, but also highlights the polymeric probe structure with high renal clearance.

An Activatable Polymeric Reporter for Near-Infrared Fluorescent and Photoacoustic Imaging of Invasive Cancer.

Discriminative detection of invasive and noninvasive breast cancers is crucial for their effective treatment and prognosis. However, activatable probes able to do so in vivo are rare. Herein, we report an activatable polymeric reporter (P-Dex) that specifically turns on near-infrared (NIR) fluorescent and photoacoustic (PA) signals in response to the urokinase-type plasminogen activator (uPA) overexpressed in invasive breast cancer. P-Dex has a renal-clearable dextran backbone that is linked with a NIR dye caged with an uPA-cleavable peptide substrate. Such a molecular design allows P-Dex to passively target tumors, activate NIR fluorescence and PA signals to effectively distinguish invasive MDA-MB-231 breast cancer from noninvasive MCF-7 breast cancer, and ultimately undergo renal clearance to minimize the toxicity potential. Thus, this polymeric reporter holds great promise for the early detection of malignant breast cancer.

[Terpenoids and sterols from Ricinus communis and their activities against diabetes].

Seven terpenoids and three sterols were isolated from the methanol extracts of the aerial parts of Ricinus communis by chromatography methods and their structures were identified by spectra analysis as ficusic acid( 1), phytol(2), callyspinol(3) , lupeol(4), 30-norlupan-3beta-ol-20-one(5) , lup-20(29)-en-3beta,15alpha-diol(6) , acetylaleuritolic acid( 7), stigmast4-en-3-one(8) , stig-mast-4-en-6beta-ol-3-one(9) , and stigmast4-en-3,6-dione(10). Compounds 1-3 and 5-10 were obtained from this species for the first time and 5 and 6 showed significant inhibitive activity and good selectivity against 11beta-HSD of mouse and human in vitro. [Key words] Ricinus communis; terpenoids; sterols; 11beta-HSD

Isolation of SFRS3 gene and its differential expression during metamorphosis involving eye migration of Japanese flounder Paralichthys olivaceus.

Both eyes of flatfishes are located on one side of the body due to asymmetrical eye migration. The molecular mechanisms underlying such asymmetry is poorly understood. As an initial step, we have adopted suppression subtractive hybridization for the identification of upregulated genes during metamorphosis involving eye migration in Japanese flounder, Paralichthys olicaceus. One of the upregulated genes was identified as the splicing factor arginine/serine rich-3 (SFRS3). Sequence analysis of SFRS3 revealed that it encodes a protein of 168 amino acids containing the typical eukaryotic RNA recognition motif (RRM) and an arginine/serine-rich region. The overall amino acid sequences of the Japanese flounder SFRS3 was highly conserved with that of other organisms. The expression of flounder SFRS3 gene increased sharply from the beginning of metamorphosis and reached a high level of expression at stage H of metamorphosis 43 days after hatching. The SFRS3 gene upregulation was mainly limited to the head region, particularly in the rapidly proliferative tissues, the lateral ethmoid and "skin thickness" on blind side, which are thought as two proliferative tissues to push the eye movement. In spite of the upregulated expression of SFRS3 during metamorphosis, its role in metamorphosis involving eye migration requires further studies.