Dual role of CD73 as a signaling molecule and adenosine-generating enzyme in colorectal cancer progression and immune evasion.

Metastasis and limited benefits of immune checkpoint blockade are two obstacles to the battle against colorectal cancer (CRC). CD73, encoded by the gene 5'-Nucleotidase Ecto (NT5E), is a major enzyme that generates extracellular adenosine. However, whether CD73 affects cancer progression and immune response in CRC remains unclear. Here, the clinical significance of CD73 was assessed in human CRC specimens using immunohistochemistry and bioinformatic analyses. We demonstrated that CD73 is elevated in CRC tissues, particularly in those with metastasis, and correlates with poor prognosis. Gain- and loss-of-function experiments demonstrate that tumor CD73 supports tumor progression and impairs the viability and effector functions of CD8+ T cells. Targeting CD73 on CRC cells reduces their malignant phenotypes and improves the anti-cancer response of CD8+ T cells in the tumor microenvironment (TME). Moreover, the combination of CD73 blockade and PD-1 inhibitors exhibited enhanced anti-cancer effects when compared to a single-agent treatment. Thus, CD73 may be a promising target in the treatment of CRC.

Preoperative administration of a biomimetic platelet nanodrug enhances postoperative drug delivery by bypassing thrombus.

The postoperative thrombus attached to the damaged blood vessels severely obstructs drugs from crossing the damaged blood-brain barrier (BBB) and targeting residual glioma cells around surgical margins, leading to glioblastoma (GBM) recurrence. A thrombus-bypassing, BBB-crossing, and surgical margin-targeted nanodrug is needed to address this phenomenon. Encouraged by the intrinsic damaged vascular endothelium chemotaxis of platelets, a platelet membrane-coated nanodrug (PM-HDOX) delivering doxorubicin (DOX) for postoperative GBM treatment is proposed and systematically investigated. Because surgery damages the vascular endothelium on the BBB around the surgical margin, the platelet membrane coating endows PM-HDOX with its inherent capacity to cross the broken BBB and target the surgical margin. Moreover, preoperative administration combined with fast-targeted PM-HDOX can realize the potential of bypassing thrombus. In GBM resection models, PM-HDOX with preoperative administration demonstrated significantly enhanced BBB-crossing and surgical margin-targeted efficacy. In particular, the PM-HDOX intensities around the surgical margins of the preoperative administration group were more than twice that of the postoperative administration group due to bypassing the thrombus formed in the broken BBB. In the antitumor experiment, the preoperative administration of PM-HDOX significantly inhibited the growth of postoperative residual tumors and prolonged the median survival time of mice. In conclusion, preoperative administration of a biomimetic platelet nanodrug can be an efficient and promising drug delivery strategy for residual GBM after surgery.

Calcium signaling in cancer progression and therapy.

The old Greek aphorism 'Panta Rhei' ('everything flows') is true for all living things in general. As a dynamic process, calcium signaling plays fundamental roles in cellular activities under both normal and pathological conditions, with recent researches uncovering its involvement in cell proliferation, migration, survival, gene expression, and more. The major question we address here is how calcium signaling affects cancer progression and whether it could be targeted to combine with classic chemotherapeutics or emerging immunotherapies to improve their efficacy.

Prrx1 promotes stemness and angiogenesis via activating TGF-ß/smad pathway and upregulating proangiogenic factors in glioma.

Glioma is one of the most lethal cancers with highly vascularized networks and growing evidences have identified glioma stem cells (GSCs) to account for excessive angiogenesis in glioma. Aberrant expression of paired-related homeobox1 (Prrx1) has been functionally associated with cancer stem cells including GSCs. In this study, Prrx1 was found to be markedly upregulated in glioma specimens and elevated Prrx1 expression was inversely correlated with prognosis of glioma patients. Prrx1 potentiated stemness acquisition in non-stem tumor cells (NSTCs) and stemness maintenance in GSCs, accompanied with increased expression of stemness markers such as SOX2. Prrx1 also promoted glioma angiogenesis by upregulating proangiogenic factors such as VEGF. Consistently, silencing Prrx1 markedly inhibited glioma proliferation, stemness, and angiogenesis in vivo. Using a combination of subcellular proteomics and in vitro analyses, we revealed that Prrx1 directly bound to the promoter regions of TGF-ß1 gene, upregulated TGF-ß1 expression, and ultimately activated the TGF-ß/smad pathway. Silencing TGF-ß1 mitigated the malignant behaviors induced by Prrx1. Activation of this pathway cooperates with Prrx1 to upregulate the expression of stemness-related genes and proangiogenic factors. In summary, our findings revealed that Prrx1/TGF-ß/smad signal axis exerted a critical role in glioma stemness and angiogeneis. Disrupting the function of this signal axis might represent a new therapeutic strategy in glioma patients.

Calcium Channel Blocker Nifedipine Suppresses Colorectal Cancer Progression and Immune Escape by Preventing NFAT2 Nuclear Translocation.

Abnormal activation of calcium channels has been shown to play crucial roles in tumor occurrence and development. However, the role of inhibitors targeting calcium channels in tumor progression and immune regulation remains unclear, and their clinical applications are still limited. We show that nifedipine (NIFE), a calcium channel blocker, inhibits calcium influx to impair nuclear factor of activated T cell 2 (NFAT2) dephosphorylation, activation, and nuclear translocation, thus preventing transcriptional activation of downstream signaling molecules to suppress colorectal cancer (CRC) proliferation and metastasis. In addition, NIFE decreases expression of programmed death-ligand 1 (PD-L1) on CRC cells and programmed death-1 (PD-1) on CD8+ T cells and reactivates tumor immune monitoring, which may stimulate or enhance PD-1-based antitumor immunotherapy. Our findings provide direct evidence that NIFE is a promising clinical therapy to treat patients with advanced CRC by affecting the tumor itself and tumor immunity. NIFE may be a promising therapeutic option to enhance effectiveness of immune checkpoint blockade therapy in CRC.

Clinical effectiveness and micro-perfusion alteration of Jingui external lotion in patients with knee osteoarthritis: study protocol for a randomized controlled trial.

BACKGROUND: Knee osteoarthritis is a major cause of disability in the aging population. Based on pathological, magnetic resonance imaging (MRI) and arthroscopy studies, progressive osteoarthritis involves all tissues of the joint and includes bone marrow lesions, synovial proliferation, fat pad inflammation, and high subchondral bone turnover. Recent research suggests that abnormal perfusion in bone marrow lesions, fat pads, and subchondral bone is associated with pain in knee osteoarthritis, and that dynamic contrast-enhanced MRI is a promising method for studying micro-perfusion alteration in knee osteoarthritis. Traditional Chinese Medicine approaches have been employed for thousands of years to relieve knee osteoarthritis pain. Among herbal medicines, the Jingui external lotion is the preferred and most commonly used method in China to reduce pain in patients with knee osteoarthritis; however, there is a lack of validated evidence for its effectiveness. The purpose of this study is to explore the effectiveness of Jingui external lotion for the management of painful knee osteoarthritis in a short-term study. In addition, we will assess micro-perfusion alteration in the patellar fat pad as well as the femur and tibia subchondral bone via dynamic contrast-enhanced MRI. METHODS/DESIGN: This trial is a randomized, controlled study. A total of 168 patients will be randomized into the following two groups: 1) the Jingui external lotion group (treatment group); and 2) the placebo lotion group (control group). In both groups, lotion fumigation and external washing of the patients' knees will be administered twice a day for 14 consecutive days. Follow-up will be at regular intervals during a 4-week period with a visual analog scale to assess pain, and additional characterization with the Western Ontario and McMaster Universities Index score; rescue medication will be recorded as the extent and time pattern. In addition, micro-perfusion alteration in the patellar fat pad, femur and tibia subchondral bone will be assessed via dynamic contrast-enhanced MRI. DISCUSSION: This study will provide clinical evidence of the efficacy of Jingui external lotion in treating knee osteoarthritis, and it will be the first randomized controlled trial to investigate micro-perfusion alteration of knee osteoarthritis with Traditional Chinese Medicine external lotion via dynamic contrast-enhanced MRI. TRIAL REGISTRATION: ClinicalTrials.gov identifier: ChiCTR-TRC-14004727 ; 31 May 2014.