Proteomic Profiling of Serum Extracellular Vesicles Identifies Diagnostic Signatures and Therapeutic Targets in Breast Cancer.

Analysis of extracellular vesicles (EVs) is a promising noninvasive liquid biopsy approach for breast cancer (BC) detection, prognosis, and therapeutic monitoring. A comprehensive understanding of the characteristics and proteomic composition of BC-specific EVs from human samples is required to realize the potential of this strategy. In this study, we applied a mass spectrometry-based, data-independent acquisition (DIA) proteomic approach to characterize human serum EVs derived from patients with BC (n = 126) and healthy donors (HDs, n = 70) in a discovery cohort and validated the findings in five independent cohorts. Examination of the EV proteomes enabled construction of specific EV protein classifiers for diagnosing BC and distinguishing patients with metastatic disease. Of note, TALDO1 was found to be an EV biomarker of distant metastasis of BC. In vitro and in vivo analysis confirmed the role of TALDO1 in stimulating BC invasion and metastasis. Finally, high-throughput molecular docking and virtual screening of a library consisting of 271,380 small molecules identified a potent TALDO1 allosteric inhibitor, AO-022, which could inhibit BC migration in vitro and tumor progression in vivo. Together, this work elucidates the proteomic alterations in the serum EVs of BC patients to guide development of improved diagnosis, monitoring, and treatment strategies.

A novel TNKS/USP25 inhibitor blocks the Wnt pathway to overcome multi-drug resistance in TNKS-overexpressing colorectal cancer.

Modulating Tankyrases (TNKS), interactions with USP25 to promote TNKS degradation, rather than inhibiting their enzymatic activities, is emerging as an alternative/specific approach to inhibit the Wnt/ß-catenin pathway. Here, we identified UAT-B, a novel neoantimycin analog isolated from Streptomyces conglobatus, as a small-molecule inhibitor of TNKS-USP25 protein-protein interaction (PPI) to overcome multi-drug resistance in colorectal cancer (CRC). The disruption of TNKS-USP25 complex formation by UAT-B led to a significant decrease in TNKS levels, triggering cell apoptosis through modulation of the Wnt/ß-catenin pathway. Importantly, UAT-B successfully inhibited the CRC cells growth that harbored high TNKS levels, as demonstrated in various in vitro and in vivo studies utilizing cell line-based and patient-derived xenografts, as well as APCmin/+ spontaneous CRC models. Collectively, these findings suggest that targeting the TNKS-USP25 PPI using a small-molecule inhibitor represents a compelling therapeutic strategy for CRC treatment, and UAT-B emerges as a promising candidate for further preclinical and clinical investigations.

Hereditary hemorrhagic telangiectasis with juvenile polyposis syndrome: a case report.

Hereditary hemorrhagic telangiectasis (HHT) and juvenile polyposis syndrome (JPS) are both relatively rare hereditary disorders. It has been reported that patients with SMAD4 mutations may suffer from both HHT and JPS, defined as JPS/HHT. To improve the understanding and diagnosis of these diseases, we herein report a case of a 17-year-old male with abdominal pain and hematochezia. Low-tension computed tomography (CT) of the small intestine showed intussusception. Combined with the patient's medical history of nasal bleeding and pulmonary arteriovenous fistula (pAVF) embolism, a final diagnosis of JPS/HHT was reached, according to the Curaçao Diagnostic Criteria. The possibility of JPS/HHT should be considered in patients with epistaxis and intussusception.

Multifunctional hydrogel based on dopamine-modified hyaluronic acid, gelatin and silver nanoparticles for promoting abdominal wall defect repair.

Abdominal wall defects are often accompanied by severe infections and complications, creating a significant challenge for clinicians. There is an urgent need to develop a novel wound dressing that can effectively prevent intra-abdominal infection and promote the healing of defective abdominal walls. Based on a hydrogel dressing containing hyaluronic acid (HA) and gelatin (GT), herein we integrated dopamine with a catechol structure to enhance its antioxidant and adherent properties. HA is oxidized to form an aldehyde group, and subsequently grafted with dopamine. The dopamine-modified HA undergoes amidation reaction with GT at different concentrations. In addition, silver nanoparticles (AgNPs) were introduced to the hydrogel to enhance the antibacterial properties. The in vitro studies on GT/DA-HA demonstrated excellent physical and chemical properties, biodegradability, and biocompatibility. In a rat full-thickness skin defect model and a full-thickness abdominal wall defect model, the GT/DA-HA hydrogel could accelerate the healing process by improving wet adhesion, reducing wound inflammation, and promoting angiogenesis and formation of granulation tissues. The multifunctional hydrogel developed in this study shows great potential for treating full-thickness abdominal wall defects.

Developing patient-derived organoids to predict PARP inhibitor response and explore resistance overcoming strategies in ovarian cancer.

With the common use of poly ADP-ribose polymerase inhibitors (PARPi) for the man-agement of epithelial ovarian cancer (EOC) across the treatment life cycle, there is a critical need for the development of functional tests, as a complementary to genomic assays, in the study of PARPi sensitivity and resistance. Patient-derived organoids (PDOs) are found feasible for rapid functional testing and predicting drug response. Here, we established a series of PDOs from EOC and tested the sensitivity of seven cases to various agents including PARPi. PDOs recapitulated patient clinical response to platinum chemotherapy and displayed drug response heterogeneity to targeted agents including PARPi. Of three PDOs harboring mutational signature of homologous recombination repair (HRR) deficiency, two were PARPi sensitive while one was inherent resistant. Another PDO derived from a patient who relapsed during olaparib maintenance therapy was found acquired resistant to PARPi. Subsequent functional analysis revealed the potential resistant mechanisms related to replication fork protection and HRR functional restoration, and combination strategies targeting the mechanisms could reverse the resistance. Our research demonstrated the capacity of EOC PDOs for evaluating the sensitivity to PARPi under different settings, exploring mechanisms of resistance, and identifying effective combined strategies, which has implications for the clinical application of PARPi.

Stichoposide C Exerts Anticancer Effects on Ovarian Cancer by Inducing Autophagy via Inhibiting AKT/mTOR Pathway.

PURPOSE: Stichoposide C (STC) is a triterpene glycoside isolated from Thelenota ananas, which is previously demonstrated to wide spectrum of anticancer effects against various tumor cells. However, the antitumor effects and underlying molecular mechanisms in ovarian cancer (OC) cells are not fully understood. Here, we examined if and through which mechanisms STC exerts anticancer effects on OC. METHODS: CCK-8 and colony formation assays were used to detect cell viability and proliferation. Flow cytometry was used to detect apoptosis and cell cycle arrest. Protein expression and phosphorylation were measured by Western blotting analysis. Confocal fluorescence microscopy was used to observe the autophagy flux. Autophagosome formation was observed via transmission electron microscopy. Antitumor effect of STC was investigated in patient-derived organoids (PDOs) and A2780 subcutaneous xenograft tumors. RESULTS: STC was found that not only exerted antiproliferation activity and apoptosis but also induced autophagy. Mechanistically, STC induced autophagy via inhibited the AKT/mTOR signaling pathway in ovarian cancer cells. In addition, STC and an autophagy inhibitor 3-methyladenine (3-MA) combination treatment showed significant synergetic effects on inhibiting proliferation and promoting apoptosis in vitro. Consistent with cell experiments, STC also inhibited the growth of two OC PDOs. Finally, STC markedly reduced the growth of A2780 subcutaneous xenograft tumors without organ toxicity and activated autophagy in vivo. CONCLUSION: Stichoposide C exerts in vitro and in vivo anticancer effects on ovarian cancer by inducing autophagy via inhibiting AKT/mTOR pathway. The findings warrant further prove for STC as a potential therapeutic agent for ovarian cancer.

The role of patient-derived ovarian cancer organoids in the study of PARP inhibitors sensitivity and resistance: from genomic analysis to functional testing.

Epithelial ovarian cancer (EOC) harbors distinct genetic features such as homologous recombination repair (HRR) deficiency, and therefore may respond to poly ADP-ribose polymerase inhibitors (PARPi). Over the past few years, PARPi have been added to the standard of care for EOC patients in both front-line and recurrent settings. Next-generation sequencing (NGS) genomic analysis provides key information, allowing for the prediction of PARPi response in patients who are PARPi naïve. However, there are indeed some limitations in NGS analyses. A subset of patients can benefit from PARPi, despite the failed detection of the predictive biomarkers such as BRCA1/2 mutations or HRR deficiency. Moreover, in the recurrent setting, the sequencing of initial tumor does not allow for the detection of reversions or secondary mutations restoring proficient HRR and thus leading to PARPi resistance. Therefore, it becomes crucial to better screen patients who will likely benefit from PARPi treatment, especially those with prior receipt of maintenance PARPi therapy. Recently, patient-derived organoids (PDOs) have been regarded as a reliable preclinical platform with clonal heterogeneity and genetic features of original tumors. PDOs are found feasible for functional testing and interrogation of biomarkers for predicting response to PARPi in EOC. Hence, we review the strengths and limitations of various predictive biomarkers and highlight the role of patient-derived ovarian cancer organoids as functional assays in the study of PARPi response. It was found that a combination of NGS and functional assays using PDOs could enhance the efficient screening of EOC patients suitable for PARPi, thus prolonging their survival time.

Niraparib as Maintenance Therapy in Germline ATM-mutated and Somatic BRCA2-mutated Ovarian Cancer with Brain Metastases: A Case Report and Literature Review.

Brain metastases from epithelial ovarian cancer are very rare with an incidence of only 1-2.5%. Many therapeutic methods such as surgery, irradiation and chemotherapy do produce survival benefits, but the overall outcome remains unsatisfactory. The BRCA (breast cancer susceptibility gene) mutation status seems to be associated with the development of brain metastases from ovarian cancer and these patients may benefit from treatment with PARP (poly ADP ribose polymerase) inhibitors. Here is a case where a Chinese female patient diagnosed with high-grade serous ovarian cancer with brain metastases was detected to have known germline ATM mutation and somatic BRCA2 mutation. The patient underwent whole brain radiotherapy and systemic chemotherapy, commenced niraparib as maintenance treatment and then presented considerable clinical and radiological response.