Dual-driven nanomotors enable tumor penetration and hypoxia alleviation for calcium overload-photo-immunotherapy against colorectal cancer.

The treatment efficacies of conventional medications against colorectal cancer (CRC) are restricted by a low penetrative, hypoxic, and immunosuppressive tumor microenvironment. To address these restrictions, we developed an innovative antitumor platform that employs calcium overload-phototherapy using mitochondrial N770-conjugated mesoporous silica nanoparticles loaded with CaO2 (CaO2-N770@MSNs). A loading level of 14.0 wt% for CaO2-N770@MSNs was measured, constituting an adequate therapeutic dosage. With the combination of oxygen generated from CaO2 and hyperthermia under near-infrared irradiation, CaO2-N770@MSNs penetrated through the dense mucus, accumulated in the colorectal tumor tissues, and inhibited tumor cell growth through endoplasmic reticulum stress and mitochondrial damage. The combination of calcium overload and phototherapy revealed high therapeutic efficacy against orthotopic colorectal tumors, alleviated the immunosuppressive microenvironment, elevated the abundance of beneficial microorganisms (e.g., Lactobacillaceae and Lachnospiraceae), and decreased harmful microorganisms (e.g., Bacteroidaceae and Muribaculaceae). Moreover, together with immune checkpoint blocker (αPD-L1), these nanoparticles showed an ability to eradicate both orthotopic and distant tumors, while potentiating systemic antitumor immunity. This treatment platform (CaO2-N770@MSNs plus αPD-L1) open a new horizon of synergistic treatment against hypoxic CRC with high killing power and safety.

Near-Infrared-Enpowered Nanomotor-Mediated Targeted Chemotherapy and Mitochondrial Phototherapy to Boost Systematic Antitumor Immunity.

Phototherapy is an important strategy to inhibit tumor growth and activate antitumor immunity. However, the effect of photothermal/photodynamic therapy (PTT/PDT) is restricted by limited tumor penetration depth and unsatisfactory potentiation of antitumor immunity. Here, a near-infrared (NIR)-driven nanomotor is constructed with a mesoporous silicon nanoparticle (MSN) as the core, end-capped with Antheraea pernyi silk fibroin (ApSF) comprising arginine-glycine-aspartate (RGD) tripeptides. Upon NIR irradiation, the resulting ApSF-coated MSNs (DIMs) loading with photosensitizers (ICG derivatives, IDs) and chemotherapeutic drugs (doxorubicin, Dox) can efficiently penetrate into the internal tumor tissues and achieve effective phototherapy. Combined with chemotherapy, a triple-modal treatment (PTT, PDT, and chemotherapy) approach is developed to induce the immunogenic cell death of tumor cells and to accelerate the release of damage-associated molecular patterns. In vivo results suggest that DIMs can promote the maturation of dendritic cells and surge the number of infiltrated immune cells. Meanwhile, DIMs can polarize macrophages from M2 to M1 phenotypes and reduce the percentages of immunosuppressive Tregs, which reverse the immunosuppressive tumor microenvironment and activate systemic antitumor immunity. By achieving synergistic effects on the tumor inhibition and the antitumor immunity activation, DIMs show great promise as new nanoplatforms to treat metastatic breast cancer.

Multi-responsive nanotheranostics with enhanced tumor penetration and oxygen self-producing capacities for multimodal synergistic cancer therapy.

Incorporation of multiple functions into one nanoplatform can improve cancer diagnostic efficacy and enhance anti-cancer outcomes. Here, we constructed doxorubicin (DOX)-loaded silk fibroin-based nanoparticles (NPs) with surface functionalization by photosensitizer (N770). The obtained nanotheranostics (N770-DOX@NPs) had desirable particle size (157 nm) and negative surface charge (-25 mV). These NPs presented excellent oxygen-generating capacity and responded to a quadruple of stimuli (acidic solution, reactive oxygen species, glutathione, and hyperthermia). Surface functionalization of DOX@NPs with N770 could endow them with active internalization by cancerous cell lines, but not by normal cells. Furthermore, the intracellular NPs were found to be preferentially retained in mitochondria, which were also efficient for near-infrared (NIR) fluorescence imaging, photothermal imaging, and photoacoustic imaging. Meanwhile, DOX could spontaneously accumulate in the nucleus. Importantly, a mouse test group treated with N770-DOX@NPs plus NIR irradiation achieved the best tumor retardation effect among all treatment groups based on tumor-bearing mouse models and a patient-derived xenograft model, demonstrating the unprecedented therapeutic effects of trimodal imaging-guided mitochondrial phototherapy (photothermal therapy and photodynamic therapy) and chemotherapy. Therefore, the present study brings new insight into the exploitation of an easy-to-use, versatile, and robust nanoplatform for programmable targeting, imaging, and applying synergistic therapy to tumors.

Pluronic F127-Modified Electrospun Fibrous Meshes for Synergistic Combination Chemotherapy of Colon Cancer.

Colon cancer ranks as the third most common malignancy in the world. Combination chemotherapy, resorting to electrospun fibrous technology, has been considered as a promising strategy to exert synergistic effects in colon cancer treatment. Herein, we manufactured various pluronic F127 (PF127)-modified electrospun fibrous meshes with different weight ratios of camptothecin (CPT) and curcumin (CUR). The fluorescence characterization of the obtained PF127-CPT-meshes, PF127-CUR-meshes, and PF127-CPT/CUR-meshes (2:1) showed that CPT and CUR were evenly distributed within individual fibers of these meshes. Drug release experiments revealed that both types of drugs could be released from fibrous meshes simultaneously and sustainably. Importantly, these meshes exhibited strong in vitro anti-colon cancer activities, compared with the control meshes without drugs. Moreover, the combination index values of the PF127-CPT/CUR-meshes (CPT/CUR weight ratio = 5:1, 3:1, or 2:1) were <0.5 after incubation for respective 24 and 36 h, indicating the synergistic anti-colon cancer effects of CPT and CUR in fibrous meshes. Collectively, these results demonstrate that PF127-CPT/CUR-meshes can be developed as an efficient implantable system for effective synergistic treatment of colon cancer.

HIF-1α as a Regulator of BMP2-Induced Chondrogenic Differentiation, Osteogenic Differentiation, and Endochondral Ossification in Stem Cells.

BACKGROUND/AIMS: Joint cartilage defects are difficult to treat due to the limited self-repair capacities of cartilage. Cartilage tissue engineering based on stem cells and gene enhancement is a potential alternative for cartilage repair. Bone morphogenetic protein 2 (BMP2) has been shown to induce chondrogenic differentiation in mesenchymal stem cells (MSCs); however, maintaining the phenotypes of MSCs during cartilage repair since differentiation occurs along the endochondral ossification pathway. In this study, hypoxia inducible factor, or (HIF)-1α, was determined to be a regulator of BMP2-induced chondrogenic differentiation, osteogenic differentiation, and endochondral bone formation. METHODS: BMP2 was used to induce chondrogenic and osteogenic differentiation in stem cells and fetal limb development. After HIF-1α was added to the inducing system, any changes in the differentiation markers were assessed. RESULTS: HIF-1α was found to potentiate BMP2-induced Sox9 and the expression of chondrogenesis by downstream markers, and inhibit Runx2 and the expression of osteogenesis by downstream markers in vitro. In subcutaneous stem cell implantation studies, HIF-1α was shown to potentiate BMP2-induced cartilage formation and inhibit endochondral ossification during ectopic bone/cartilage formation. In the fetal limb culture, HIF-1α and BMP2 synergistically promoted the expansion of the proliferating chondrocyte zone and inhibited chondrocyte hypertrophy and endochondral ossification. CONCLUSION: The results of this study indicated that, when combined with BMP2, HIF-1α induced MSC differentiation could become a new method of maintaining cartilage phenotypes during cartilage tissue engineering.

The use of pneumatic tourniquet in total knee arthroplasty: a meta-analysis.

BACKGROUND: Pneumatic tourniquet use in total knee arthroplasty (TKA) is always a controversial issue. The aim of the present study is to assess the effectiveness and safety of its use in patients receiving primary unilateral TKA, and to explore the most safe and effective protocols. MATERIALS AND METHODS: This review was based on cochrane methodology for conducting meta-analysis. Only randomized controlled trials (RCTs) were eligible for this study. The participants were adults who had undergone primary unilateral TKA. The Review Manager Database (RevMan version 5.0, The Cochrane Collaboration 2008) was used to analyze the dates of the selected studies. RESULTS: Thirteen RCTs involving 859 patients were included in this analysis. The use of tourniquet could significantly reduce operation time (mean difference -5.01 min, P = 0.003), intraoperative blood loss (mean difference -201.85 ml, P < 0.00001) and total blood loss volumes (mean difference -125.03 ml, P = 0.61). But postoperative (mean difference 45.99 ml, P = 0.68) were slightly increased in that situation. With respect to surgical complications, a tendency of increasing risk ratio was observed for tourniquet group. CONCLUSIONS: Our results indicate that tourniquet application could reduce surgical time, intraoperative blood loss and total blood loss, but increases postoperative total blood loss. With respect to postoperative complications, DVT and surgical site infection rates are relatively augmented in the tourniquet group.

[Co-expression of BMP2 and Sox9 promotes chondrogenic differentiation of mesenchymal stem cells in vitro].

OBJECTIVE: To investigate the effect of co-expression of bone morphogenetic protein 2 (BMP2) and Sox9 on chondrogenic differentiation of mesenchymal stem cells (MSCs) in vitro and provide experimental evidence for tissue engineering of cartilage. METHODS: Mouse embryonic bone marrow MSC C3H10T1/2 cells were infected with recombinant adenovirus expressing BMP2, Sox9 and green fluorescent protein (GFP) for 3-14 days, with cells infected with the adenovirus carrying GFP gene as the control. The mRNA expression of the markers of chondrogenic differentiation, including collagen type II (Col2a1), aggrecan (ACAN), and collagen type X (Col10a1), were determined by real-time PCR. Alcian blue staining was used for quantitative analysis of sulfated glycosaminoglycan in the cellular matrix. The expression of Col2a1 protein was assayed by immunohistochemical staining and Western blot analysis. RESULTS: Adenovirus-mediated BMP2 expression induced chondrogenic differentiation of C3H10T1/2 cells. Overexpression of Sox9 effectively enhanced BMP2-induced expression of the chondrogenic markers Col2a1, aggrecan and Col10a1 mRNAs, and promoted the synthesis of sulfated glycosaminoglycan and Col2a1 protein in C3H10T1/2 cells. CONCLUSION: Co-expression of BMP2 and Sox9 can promote chondrogenic differentiation of MSCs in vitro, which provides a new strategy for tissue engineering of cartilage.

Sox9 potentiates BMP2-induced chondrogenic differentiation and inhibits BMP2-induced osteogenic differentiation.

Bone morphogenetic protein 2 (BMP2) is one of the key chondrogenic growth factors involved in the cartilage regeneration. However, it also exhibits osteogenic abilities and triggers endochondral ossification. Effective chondrogenesis and inhibition of BMP2-induced osteogenesis and endochondral ossification can be achieved by directing the mesenchymal stem cells (MSCs) towards chondrocyte lineage with chodrogenic factors, such as Sox9. Here we investigated the effects of Sox9 on BMP2-induced chondrogenic and osteogenic differentiation of MSCs. We found exogenous overexpression of Sox9 enhanced the BMP2-induced chondrogenic differentiation of MSCs in vitro. Also, it inhibited early and late osteogenic differentiation of MSCs in vitro. Subcutaneous stem cell implantation demonstrated Sox9 potentiated BMP2-induced cartilage formation and inhibited endochondral ossification. Mouse limb cultures indicated that BMP2 and Sox9 acted synergistically to stimulate chondrocytes proliferation, and Sox9 inhibited BMP2-induced chondrocytes hypertrophy and ossification. This study strongly suggests that Sox9 potentiates BMP2-induced MSCs chondrogenic differentiation and cartilage formation, and inhibits BMP2-induced MSCs osteogenic differentiation and endochondral ossification. Thus, exogenous overexpression of Sox9 in BMP2-induced mesenchymal stem cells differentiation may be a new strategy for cartilage tissue engineering.