Anticancer effect of the antirheumatic drug leflunomide on oral squamous cell carcinoma by the inhibition of tumor angiogenesis.

Objectives: Leflunomide (LEF) is a conventional synthetic disease-modifying antirheumatic drug and suppresses T-cell proliferation and activity by inhibiting pyrimidine synthesis using dihydroorotase dehydrogenase (DHODH); however, several studies have demonstrated that LEF possesses anticancer and antiangiogenic effects in some malignant tumors. Therefore, we investigated the anticancer and antiangiogenic effects of LEF on oral squamous cell carcinoma (OSCC).

Methods: To evaluate the inhibitory effect of LEF on OSCC, cell proliferation and wound-healing assays using human OSCC cell lines were performed.

Phosphorylation of Serine 536 of p65(RelA) Downregulates Inflammatory Responses.

Nuclear factor-κB (NF-κB) is a transcription factor that regulates the expression of various genes involved in inflammatory diseases and immune responses. Recently, a novel transcriptional regulatory mechanism of NF-κB involving the phosphorylation of serine 536 (534 in mice; S534) of its p65 subunit was reported; however, further research is required to elucidate the physiological role of S534 phosphorylation. Therefore, we generated S534A knock-in (KI) mice, in which the S534 of p65 was substituted with alanine.

Activation of NF-κB signaling regulates ovariectomy-induced bone loss and weight gain.

Postmenopausal women experience bone loss and weight gain. To date, crosstalk between estrogen receptor signals and nuclear factor-κB (NF-κB) has been reported, and estrogen depletion enhances bone resorption by osteoclasts via NF-κB activation. However, it is unclear when and in which tissues NF-κB is activated after menopause, and how NF-κB acts as a common signaling molecule for postmenopausal weight gain and bone loss.

Nuclear factor-κB p65 subunit determines the fate of aging epithelial cells.

Nuclear factor (NF)-κB signaling is not only important for the immune and inflammatory responses but also for the normal development of epithelial cells, such as those in the skin and tooth. Here, we generated epithelial cell-specific p65-deficient (p65) mice to analyze the roles of NF-κB signaling in epithelial cell developent. Notably, p65 mice exhibited no abnormalities in their appearance compared to the control (p65) littermates.

Wnt7b expressed by hypertrophic chondrocytes is a stimulatory factor for endochondral ossification that is regulated by Smad4 activity.

Endochondral ossification contributes to longitudinal skeletal growth. Osteoblasts, which are bone-forming cells, appear close to terminally differentiated hypertrophic chondrocytes during endochondral ossification. We established mice with conditional knockout (cKO) of Smad4, an essential co-activator for transforming growth factor β family signaling.