Inhibition of Dipeptidyl Peptidase-4 Activates Autophagy to Promote Survival of Breast Cancer Cells via the mTOR/HIF-1α Pathway

DPP4, a potential tumor biomarker, and tumor therapeutic target: review

Dipeptidyl peptidase 4 (DPP4) is a serine protease widely distributed in membrane-bound and soluble forms in various tissues and organs throughout the body. DPP4 plays a role in inflammation, immune regulation, cell growth, migration and differentiation. The role of DPP4 in tumors has garnered increasing attention. Previous research has demonstrated that DPP4 contributes to the promotion of cancer in most cancers, and it may play a specific biological function through the variation in tumor cell types and expression forms. However, the expression of DDP4 in different tumor types and its specific mechanism remains unclear. In this review, we describe the structure of DPP4, summarize the recent research progress of its expression and potential mechanisms in common tumors, and discuss the development prospects of DPP4 inhibitors in tumor therapy. Although current research emphasizes the potential of DPP4 as a drug target, the incomplete understanding of its regulatory mechanisms impedes the discovery and development of new therapies against it. Further research on DPP4-related tumors is anticipated to promote its clinical application as a potential therapeutic target.

HIF-1α Mediated Regulation of Glioblastoma Malignant Phenotypes through CD47 Protein: Understanding Functions and Mechanisms

Glioblastoma (GBM) is a highly invasive and malignant primary intracranial tumor originating from glial cells, and it is associated with an extremely poor clinical prognosis. The hypoxic conditions within GBM promote various tumor cell processes such as angiogenesis, proliferation, migration, invasion, and drug resistance. A key aspect of tumor adaptation to the hypoxic environment and the promotion of malignant behaviors is the regulation of HIF-1α signaling pathways. However, the specific pathogenic mechanisms involving HIF-1α in GBM have not been thoroughly investigated. This study reveals significant overexpression of both HIF-1α and CD47 in GBM. Patients with high HIF-1α levels and CD47 expression had significantly reduced overall survival and disease-free survival times. Furthermore, a positive correlation was observed between the expression levels of HIF-1α and CD47 in GBM. Lentivirus-mediated knockdown of HIF-1α protein and plasmid-based overexpression of CD47 protein simultaneously enhanced cell proliferation, clonogenic potential and cell migration abilities in GBM, and HIF-1α was found to regulate key pathways, including the P-PI3K/P-AKT, SOX2/OCT4 and MMP2/MMP9 pathways, in GBM.

Cancer biology in diabetes update: Focusing on antidiabetic drugs

The association of type 2 diabetes with certain cancer risk has been of great interest for years. However, the effect of diabetic medications on cancer development is not fully understood. Prospective clinical trials have not elucidated the long-term influence of hypoglycemic drugs on cancer incidence and the safety for cancer-bearing patients with diabetes, whereas numerous preclinical studies have shown that antidiabetic drugs could have an impact on carcinogenesis processes beyond the glycemic control effect. Because there is no evidence of the safety profile of antidiabetic agents on cancer biology, careful consideration would be required when prescribing any medicines to patients with diabetes and existing tumor. In this review, we discuss the potential influence of each diabetes therapy in cancer 'initiation', 'promotion' and 'progression'.