Bladder cancer (BC) is the second most common urologic malignancy and the ninth most common malignancy worldwide. Surgical resection is the mainstay of treatment for patients with early-stage disease, whereas therapeutic options are limited for patients with advanced-stage or residual BC. Programmed cell death ligand-1 (PD-L1) is an important target for immunotherapy. It is known that PD-L1 is overexpressed in BC; a clinical trial involving PD-L1 immune checkpoint inhibitors in advanced BC is ongoing. In the present study, we used Western blot and quantitative real-time PCR (qPCR) to define the expression level of PD-L1 after cisplatin treatment in BC-derived cell lines. The signal activation was also evaluated by Western blot in BC-derived cell lines. We found that chemotherapeutic drug cisplatin can induce PD-L1 but not PD-L2 expression in BC-derived cell lines. Furthermore, the expression level of PD-L1 was increased in a dose- and time-dependent manner after cisplatin treatment. The cisplatin-induced PD-L1 expression is mainly mediated by ERK1/2 but not Akt/mTOR signal pathway. Moreover, we found that cisplatin activates transcription factor activator protein-1 (AP-1) to regulate PD-L1 expression. The chemotherapy drug such as cisplatin may trigger resistance of BC through PD-L1 up-regulation. The present study suggests that PD-L1 antibody should be used concomitantly with chemotherapy in the setting of advanced and metastatic BC.

Osteosarcoma is an extremely common primary bone malignancy that is highly metastatic, with most deaths resulting from pulmonary metastases. The extracellular matrix protein thrombospondin‐2 (TSP‐2) is key to many biological processes, such as inflammation, wound repair and tissue remodelling. However, it is unclear as to what biological role TSP‐2 plays in human metastatic osteosarcoma. The immunochemistry analysis from osteosarcoma specimens identified marked up‐regulation of TSP‐2 in late‐stage osteosarcoma. Furthermore, we found that TSP‐2 increased the levels of matrix metallopeptidase 9 (MMP‐9) expression and thereby increased the migratory potential of human osteosarcoma cells. Osteosarcoma cells pre‐treated with an MMP‐9 monoclonal antibody (mAb), an MMP‐9 inhibitor, or transfected with MMP‐9 small interfering RNA (siRNA) reduced the capacity of TSP‐2 to potentiate cell migration. TSP‐2 treatment activated the PLCβ, PKCα, c‐Src and nuclear kappa factor B (NF‐κB) signalling pathways, while the specific siRNA, inhibitors and mutants of these cascades reduced TSP‐2‐induced stimulation of migration activity. Knockdown of TSP‐2 expression markedly reduced cell metastasis in cellular and animal experiments. It appears that an interaction between TSP‐2 and integrin αvβ3 activates the PLCβ, PKCα and c‐Src signalling pathways and subsequently activates NF‐κB signalling, increasing MMP‐9 expression and stimulating migratory activity amongst human osteosarcoma cells.

Bladder cancer (BC), a common urologic cancer, is the fifth most frequently diagnosed tumor worldwide. hsa‑miR‑34a displays antitumor activity in several types of cancer. However, the functional mechanisms underlying hsa‑miR‑34a in BC remains largely unknown. We observed that hsa‑mir‑34a levels were significantly and negatively associated with clinical disease stage as well as regional lymph node metastasis in human BC. In a series of in vitro investigations, overexpression of hsa‑miR‑34a inhibited cell migration and invasion in BC cell lines 5637 and UMUC3 as detected by Transwell assays. We further found that hsa‑miR‑34a inhibited cell migration and invasion by silencing matrix metalloproteinase‑2 (MMP‑2) expression and thus interrupting MMP‑2‑mediated cell motility. Our analysis of BC datasets from The Cancer Genome Atlas database revealed a negative correlation between hsa‑miR‑34a and MMP‑2. Moreover, higher MMP‑2 protein expression was observed in the BC tissues when compared with that noted in the normal tissue. MMP‑2 levels were also significantly associated with clinical disease stage and poor survival rate in human BC. These findings indicate that MMP‑2 plays a critical role in regulating BC progression. Therefore, hsa‑miR‑34a is a promising treatment to target MMP‑2 for the prevention and inhibition of cell migration and invasion in BC.

Bladder cancer (BC) is the second most common urological tumour in Western countries. Approximately, 80% of patients with BC will present with non‐muscle invasive bladder cancer (NMIBC), whereas a quarter will have muscle invasive disease (MIBC) at the time of BC diagnosis. However, patients with NMIBC are at risk of BC recurrence or progression into MIBC, and an MIBC prognosis is determined by the presence of progression and metastasis. Matrix metalloproteinase 2 (MMP2), a type of matrix metalloproteinase (MMP), plays a major role in tumour invasion and is well‐characterized in BC prognosis. In BC, the mechanisms regulating MMP2 expression, and, in turn, promote cancer invasion, have hardly been explored. Thrombospondin‐4 (THBS4/TSP4) is a matricellular glycoprotein that regulates multiple biological functions, including proliferation, angiogenesis, cell adhesion and extracellular matrix modelling. Based on the results of a meta‐analysis in the Gene Expression Profiling Interactive Analysis 2 database, we observed that TSP4 expression levels were consistent with overall survival (OS) rate and BC progression, with the highest expression levels observed in the advanced stages of BC and associated with poor OS rate. In our pilot experiments, incubation with recombinant TSP4 promoted the migration and invasion in BC cells. Furthermore, MMP2 expression levels increased after recombinant TSP4 incubation. TSP4‐induced‐MMP2 expression and cell motility were regulated via the AKT signalling pathway. Our findings facilitate further investigation into TSP4 silencing‐based therapeutic strategies for BC.

The CXC chemokine ligand‐13 (CXCL13) is a chemoattractant of B cells and has been implicated in the progression of many cancers. So far, CXCL13 and its related receptor CXCR5 have been proved to regulate cancer cell migration as well as tumour metastasis. However, the role of CXCL13‐CXCR5 axis in metastasis of lung cancer is still poorly understood. In this study, we found that CXCL13 and CXCR5 were commonly up‐regulated in lung cancer specimens compared with normal tissues among different cohorts. Our evidence showed that CXCL13 obviously promoted migration of lung cancer cells, and this effect was mediated by vascular cell adhesion molecule‐1 (VCAM‐1) expression. We also confirmed that CXCR5, the major receptor responsible for CXCL13 function, was required for CXCL13‐promoted cell migration. We also test the candidate components which are activated after CXCL13 treatment and found that phospholipase C‐β (PLCβ), protein kinase C‐α (PKCα) and c‐Src signalling pathways were involved in CXCL13‐promoted cell migration and VCAM‐1 expression in lung cancer cells. Finally, CXCL13 stimulated NF‐κB transcription factor in lung cancer cells, contributing to VCAM‐1 expression in translational level. These evidences propose a novel insight into lung cancer metastasis which is regulated by CXCL13.

Purpose: Nuclear factor (erythroid-derived 2)-like 2, also known as NFE2L2 or NRF2, a transcription factor capable of upregulating antioxidant response element (ARE)-mediated expression and cytoprotective proteins, plays critical roles in chemoprevention, inflammation and aging. NRF2 has recently been proposed as a novel target for cancer chemoprevention. The fungicide miconazole has shown promising antiproliferative effects in cancer cells. Materials and Methods: After miconazole treatment, the p62-KEAP1-NRF2 activation was analyzed by qPCR and Western blot. The nuclear translocation indicating NRF2 activation was further confirmed by immunofluorescence. Finally, the ROS production was detected by CM-H2DCFDA staining. Results: We demonstrate in this study that miconazole dramatically increases NRF2 activation in bladder cancer cells, in a dose- and time-dependent manner. Interestingly, levels of expression of p62, a noncanonical pathway that mediates NRF2 activation, appeared to increase in accordance with NRF2. We also investigated levels of the negative regulator kelch-like ECH-associated protein 1 (KEAP1), which is involved in NRF2 activation. As expected, a decrease in KEAP1 expression was found after miconazole exposure. Confirmation of NRF2 nuclear translocation was monitored by immunofluorescence. Miconazole-induced generation of reactive oxygen species (ROS) promoted NRF2 activation. Pretreatment of bladder cancer cells with ROS scavengers abolished NRF2 expression and nuclear translocation, indicating that miconazole activates the noncanonical p62-KEAP1-NRF2 pathway, which is regulated by ROS production. Conclusion: Our study elucidates the mechanisms through which miconazole stimulates NRF2 which may contribute to cancer chemopreventive effects.