Silk fibroin hydrogel adhesive enables sealed-tight reconstruction of meniscus tears.

Despite orientationally variant tears of the meniscus, suture repair is the current clinical gold treatment. However, inaccessible tears in company with re-tears susceptibility remain unresolved. To extend meniscal repair tools from the perspective of adhesion and regeneration, we design a dual functional biologic-released bioadhesive (S-PIL10) comprised of methacrylated silk fibroin crosslinked with phenylboronic acid-ionic liquid loading with growth factor TGF-ß1, which integrates chemo-mechanical restoration with inner meniscal regeneration. Supramolecular interactions of ß-sheets and hydrogen bonds richened by phenylboronic acid-ionic liquid (PIL) result in enhanced wet adhesion, swelling resistance, and anti-fatigue capabilities, compared to neat silk fibroin gel. Besides, elimination of reactive oxygen species (ROS) by S-PIL10 further fortifies localized meniscus tear repair by affecting inflammatory microenvironment with dynamic borate ester bonds, and S-PIL10 continuously releases TGF-ß1 for cell recruitment and bridging of defect edge. In vivo rabbit models functionally evidence the seamless and dense reconstruction of torn meniscus, verifying that the concept of meniscus adhesive is feasible and providing a promising revolutionary strategy for preclinical research to repair meniscus tears.

Oncogenic KRAS Induces Arginine Auxotrophy and Confers a Therapeutic Vulnerability to SLC7A1 Inhibition in Non-Small Cell Lung Cancer.

The urea cycle is frequently rewired in cancer cells to meet the metabolic demands of cancer. Elucidation of the underlying mechanism by which oncogenic signaling mediates urea cycle reprogramming could help identify targetable metabolic vulnerabilities. In this study, we discovered that oncogenic activation of KRAS in non-small cell lung cancer (NSCLC) silenced the expression of argininosuccinate synthase 1 (ASS1), a urea cycle enzyme that catalyzes the production of arginine from aspartate and citrulline, and thereby diverted the utilization of aspartate to pyrimidine synthesis to meet the high demand for DNA replication. Specifically, KRAS signaling facilitated a hypoacetylated state in the promoter region of the ASS1 gene in a histone deacetylase 3-dependent manner, which in turn impeded the recruitment of c-MYC for ASS1 transcription. ASS1 suppression in KRAS-mutant NSCLC cells impaired the biosynthesis of arginine and rendered a dependency on the arginine transmembrane transporter SLC7A1 to import extracellular arginine. Depletion of SLC7A1 in both patient-derived organoid and xenograft models inhibited KRAS-driven NSCLC growth. Together, these findings uncover the role of oncogenic KRAS in rewiring urea cycle metabolism and identify SLC7A1-mediated arginine uptake as a therapeutic vulnerability for treating KRAS-mutant NSCLC. SIGNIFICANCE: ASS1 deficiency is induced by mutant KRAS in NSCLC to facilitate DNA synthesis and creates a dependency on SLC7A1, revealing dietary arginine restriction and SLC7A1 inhibition as potential therapeutic strategies.

Low-Dose Chemotherapy Preferentially Shapes the Ileal Microbiome and Augments the Response to Immune Checkpoint Blockade by Activating AIM2 Inflammasome in Ileal Epithelial Cells.

Intervention of the gut microbiome is a promising adjuvant strategy in cancer immunotherapy. Chemotherapeutic agents are recognized for their substantial impacts on the gut microbiome, yet their therapeutic potential as microbiome modulators remains uncertain, due to the complexity of microbiome-host-drug interactions. Here, it is showed that low-dose chemotherapy preferentially shapes the ileal microbiome to augment the extraintestinal immune response to anti-programmed death-1 (anti-PD-1) therapy without causing intestinal toxicity. Mechanistically, low-dose chemotherapy causes DNA damage restricted to highly-proliferative ileal epithelial cells, resulting in the accumulation of cytosolic dsDNA and the activation of the absent in melanoma 2 (AIM2) inflammasome. AIM2-dependent IL-18 secretion triggers the interplay between proximal Th1 cells and Paneth cells in ileal crypts, impairing the local antimicrobial host defense and resulting in ileal microbiome change. Intestinal epithelium-specific knockout of AIM2 in mice significantly attenuates CPT-11-caused IL-18 secretion, Paneth cell dysfunction, and ileal microbiome alteration. Moreover, AIM2 deficiency in mice or antibiotic microbial depletion attenuates chemotherapy-augmented antitumor responses to anti-PD1 therapy. Collectively, these findings provide mechanistic insights into how chemotherapy-induced genomic stress is transduced to gut microbiome change and support the rationale of applying low-dose chemotherapy as a promising adjuvant strategy in cancer immunotherapy with minimal toxicity.

RNA sequencing revealed the multi-stage transcriptome transformations during the development of gallbladder cancer associated with chronic inflammation.

Gallbladder cancer (GBC) is a highly malignant tumor with extremely poor prognosis. Previous studies have suggested that the carcinogenesis and progression of GBC is a multi-stage and multi-step process, but most of them focused on the genome changes. And a few studies just compared the transcriptome differences between tumor tissues and adjacent noncancerous tissues. The transcriptome changes, relating to every stage of GBC evolution, have rarely been studied. We selected three cases of normal gallbladder, four cases of gallbladder with chronic inflammation induced by gallstones, five cases of early GBC, and five cases of advanced GBC, using next-generation RNA sequencing to reveal the changes in mRNAs and lncRNAs expression during the evolution of GBC. In-depth analysis of the sequencing data indicated that transcriptome changes from normal gallbladder to gallbladder with chronic inflammation were distinctly related to inflammation, lipid metabolism, and sex hormone metabolism; transcriptome changes from gallbladder with chronic inflammation to early GBC were distinctly related to immune activities and connection between cells; and the transcriptome changes from early GBC to advanced GBC were distinctly related to transmembrane transport of substances and migration of cells. Expression profiles of mRNAs and lncRNAs change significantly during the evolution of GBC, in which lipid-based metabolic abnormalities play an important promotive role, inflammation and immune activities play a key role, and membrane proteins are very highlighted molecular changes.

Stage-specific and location-specific cartilage calcification in osteoarthritis development.

OBJECTIVES: This study investigated the stage-specific and location-specific deposition and characteristics of minerals in human osteoarthritis (OA) cartilages via multiple nano-analytical technologies. METHODS: Normal and OA cartilages were serially sectioned for micro-CT, scanning electron microscopy with energy dispersive X-ray spectroscopy, micro-Raman spectroscopy, focused ion beam scanning electron microscopy, high-resolution electron energy loss spectrometry with transmission electron microscopy, nanoindentation and atomic force microscopy to analyse the structural, compositional and mechanical properties of cartilage in OA progression. RESULTS: We found that OA progressed by both top-down calcification at the joint surface and bottom-up calcification at the osteochondral interface. The top-down calcification process started with spherical mineral particle formation in the joint surface during early-stage OA (OA-E), followed by fibre formation and densely packed material transformation deep into the cartilage during advanced-stage OA (OA-A). The bottom-up calcification in OA-E started when an excessive layer of calcified tissue formed above the original calcified cartilage, exhibiting a calcified sandwich structure. Over time, the original and upper layers of calcified cartilage fused, which thickened the calcified cartilage region and disrupted the cartilage structure. During OA-E, the calcified cartilage was hypermineralised, containing stiffer carbonated hydroxyapatite (HAp). During OA-A, it was hypomineralised and contained softer HAp. This discrepancy may be attributed to matrix vesicle nucleation during OA-E and carbonate cores during OA-A. CONCLUSIONS: This work refines our current understanding of the mechanism underlying OA progression and provides the foothold for potential therapeutic targeting strategies once the location-specific cartilage calcification features in OA are established.

"Musical dish" efficiently induces osteogenic differentiation of mesenchymal stem cells through music derived microstretch with variable frequency.

Nonuniform microstretching (NUMS) naturally occurs in real bone tissues in vivo, but its profound effects have not been identified yet. In order to explore the biological effects of NUMS and static stretch (uniform stretch [US]) on cells, a new "musical dish" device was developed. Musical signal was used to provide NUMS to cells. More stress fibers, arranging along the long axis of cells, were formed throughout the cells under NUMS, compared with US and untreated control group, although cell morphology did not show any alteration. Whole transcriptome sequencing revealed enhanced osteogenic differentiation of cells after NUMS treatment. Cells in the NUMS group showed a higher expression of bone-related genes, while genes related to stemness and other lineages were down-regulated. Our results give insights into the biological effects of NUMS and US on stem cell osteogenic differentiation, suggesting beneficial effects of micromechanical stimulus for osteogenesis. The newly developed device provides a basis for the development of NUMS derived rehabilitation technology to promote bone healing.

Association of Clinical Features of Colorectal Cancer with Circulating Tumor Cells and Systemic Inflammatory Markers.

Background: Circulating tumor cells (CTCs) in peripheral blood have been shown to reflect the prognosis of patients with colorectal cancer, and epithelial and mesenchymal markers further predict the likelihood of cancer dissemination. This study was conducted to identify possible association of clinical features of colorectal cancer with CTC counts, their subtypes, and systemic inflammatory markers. Methods: Blood samples of 316 colorectal cancer patients were used for CTC detection and subtyping with EpCAM, CK8/18/19, vimentin, and twist as biomarkers. The neutrophil/lymphocyte ratio, platelet/lymphocyte ratio, C-reactive protein/albumin ratio, lymphocyte/monocyte ratio, and systemic immune-inflammation index (SII) were also measured. The relationship between clinical data and these markers or parameters was analyzed. Results: Total CTC counts were correlated with whether there was lymph node involvement but was not correlated with TNM staging. There was a difference in mesenchymal CTCs between patients with and without lymph node involvement (P < 0.05). Also, more patients with metastasis tested positive for mesenchymal CTCs (P < 0.05). Of the systemic inflammatory markers, platelet/lymphocyte ratio was positively correlated with CTC counts (P < 0.01), and lymphocyte/monocyte ratio was negatively correlated with CTC counts (P < 0.05). Conclusions: Colorectal cancer patients with the mesenchymal markers on their CTCs are more likely to have lymph node involvement or distant metastasis than those without these markers.

Identification of an Ultrathin Osteochondral Interface Tissue with Specific Nanostructure at the Human Knee Joint.

Cartilage adheres to subchondral bone via a specific osteochondral interface tissue where forces are transferred from soft cartilage to hard bone without conferring fatigue damage over a lifetime of load cycles. However, the fine structure and mechanical properties of the osteochondral interface tissue remain unclear. Here, we identified an ultrathin ∼20-30 µm graded calcified region with two-layered micronano structures of osteochondral interface tissue in the human knee joint, which exhibited characteristic biomolecular compositions and complex nanocrystals assembly. Results from finite element simulations revealed that within this region, an exponential increase of modulus (3 orders of magnitude) was conducive to force transmission. Nanoscale heterogeneity in the hydroxyapatite, coupled with enrichment of elastic-responsive protein-titin, which is usually present in muscle, endowed the osteochondral tissue with excellent mechanical properties. Collectively, these results provide novel insights into the potential design for high-performance interface materials for osteochondral interface regeneration.

The expression of growth differentiation factor 15 in gallbladder carcinoma.

PURPOSE: This study initially explored the expression of GDF-15 in gallbladder carcinoma and its clinical significance, and analyzed the correlation between the expression of GDF-15 and the clinicopathological features as well as the prognosis of patients with gallbladder carcinoma. METHODS: Enzyme-linked immunosorbent assay (ELISA) was used to determine the expression of GDF-15 in the serum of 42 patients with gallbladder cancer. The control group included 24 patients with cholecystitis and 20 healthy volunteers. The immunohistochemical method (IHC) was used to detect the expression of GDF-15 in 42 cases of gallbladder tumor tissue and 35 cases of adjacent non-tumor gallbladder tissue specimens. RESULTS: The results of ELISA showed that the concentration of GDF-15 in serum was considerably higher in gallbladder cancer patients than that in gallbladder benign lesions and healthy volunteers (p=0.006, p<0.001). In the group of patients with gallbladder cancer, the consistence of GDF-15 in patients with lymph node metastasis was significantly higher than that of patients without lymph node metastasis (p<0.001). Immunohistochemical staining showed that the expression of GDF-15 in gallbladder carcinoma was markedly higher than that in non-tumor gallbladder tissues (p=0.003), and the high expression of GDF-15 was significantly correlated with the differentiation grade of gallbladder carcinoma and tumor TNM stage (p=0.005, p=0.002). CONCLUSION: GDF-15 is related to the occurrence and development of gallbladder cancer. GDF-15 in serum can be used as a potential marker for the diagnosis of gallbladder cancer and can be used to predict the lymph node metastasis of gallbladder cancer.