Combined checkpoint blockade (e.g., PD1/PD-L1) with traditional clinical therapies can be hampered by side effects and low tumour-therapeutic outcome, hindering broad clinical translation. Here we report a combined tumour-therapeutic modality based on integrating nanosonosensitizers-augmented noninvasive sonodynamic therapy (SDT) with checkpoint-blockade immunotherapy. All components of the nanosonosensitizers (HMME/R837@Lip) are clinically approved, wherein liposomes act as carriers to co-encapsulate sonosensitizers (hematoporphyrin monomethyl ether (HMME)) and immune adjuvant (imiquimod (R837)). Using multiple tumour models, we demonstrate that combining nanosonosensitizers-augmented SDT with anti-PD-L1 induces an anti-tumour response, which not only arrests primary tumour progression, but also prevents lung metastasis. Furthermore, the combined treatment strategy offers a long-term immunological memory function, which can protect against tumour rechallenge after elimination of the initial tumours. Therefore, this work represents a proof-of-concept combinatorial tumour therapeutics based on noninvasive tumours-therapeutic modality with immunotherapy.

Clinical decision-making on endoscopic vs. surgical resection of early gastric cardiac carcinoma remains challenging because of uncertainty on risk of lymph node metastasis. The aim of this multicenter study was to investigate risk factors of lymph node metastasis in early gastric cardiac carcinoma. Guided with the World Health Organization diagnostic criteria, we studied 2101 radical resections of early gastric carcinoma for risk factors associated with lymph node metastasis, including tumor location, gross pattern, size, histology type, differentiation, invasion depth, lymphovascular, and perineural invasion. We found that the risk of lymph node metastasis was significantly lower in early gastric cardiac carcinomas (6.7%, 33/495), compared with early gastric non-cardiac carcinomas (17.1%, 275/1606) (p < 0.0001). In early gastric cardiac carcinoma, no lymph node metastasis was identified in intramucosal carcinoma (0/193) and uncommon types of carcinomas (0/24), irrespective of the gross pattern, size, histologic type, differentiation, and invasion depth. Ulceration, size > 3 cm, and submucosal invasion were not significant independent risk factors for lymph node metastasis. In 33 early gastric cardiac carcinomas with lymph node metastasis, either lymphovascular invasion or poor differentiation was present in 16 (48.5%) cases and together in six cases. By multivariate analysis, independent risk factors of lymph node metastasis in early gastric cardiac carcinoma included lymphovascular invasion (Odds Ratio (OR): 7.6, 95% Confidence Interval (CI): 2.8-20.2) (p < 0.0001) and poor differentiation (OR: 6.0, 95% CI: 1.4-25.9) (p < 0.05). In conclusion, lymph node metastasis was not identified in early gastric cardiac intramucosal carcinoma and uncommon types of carcinoma. The risk of lymph node metastasis was also significantly lower in tumors with submucosal invasion, especially for cases without lymphovascular invasion or poor differentiation. These results lend support to the role of endoscopic therapy in the treatment of patients with early gastric cardiac carcinoma.

Mesenchymal stem cells (MSCs) are immune privileged and a cell source for tissue repair. Previous studies showed that there is systemic mobilization of osteoblastic precursors to the fracture site. We hypothesized that both systemic and local administration of allogeneic MSCs may promote fracture healing. Bone marrow-derived MSCs and skin fibroblasts were isolated from GFP Sprague–Dawley rats, cultured, and characterized. Closed transverse femoral fracture with internal fixation was established in 48 adult male Sprague–Dawley rats, which were randomly assigned into four groups receiving PBS injection, MSC systemic injection, fibroblast systemic injection, and MSC fracture site injection; 2 × 106 cells were injected at 4 days after fracture. All animals were sacrificed at 5 weeks after fracture; examinations included weekly radiograph, micro-CT, mechanical testing, histology, immunohistochemistry, and double immunofluorescence. The callus size of MSC injection groups was significantly larger among all the groups. Radiographs and 3D reconstruction images showed that the fracture gaps united in the MSC injected groups, while gaps were still seen in the fibroblast and PBS injection groups. The mechanical properties were significantly higher in the MSC injection groups than those in the fibroblast and PBS groups, but no difference was found between the MSC local and systemic injection groups. Immunohistochemistry and double immunofluorescence demonstrated that GFP-positive MSCs were present in the callus in the MSC injection groups at 5 weeks after fracture, and some differentiated into osteoblasts. Quantitative analysis revealed the number of GFP-positive cells in the callus in the MSC systemic injection group was significantly lower than that of the MSC local injection group. The proportion of GFP osteoblasts in GFP-positive cells in the MSC systemic injection group was significantly lower than that of the MSC local injection group. These findings provide critical insight for developing MSC-based therapies, and systemic injection of allogeneic MSCs may be a novel treatment method for promoting fracture repair.