Forkhead box P1 (Foxp1) in osteoblasts regulates bone mass accrual and adipose tissue energy metabolism

The function of Foxp1 represses β-adrenergic receptor transcription in the occurrence and development of bladder cancer through STAT3 activity

Bladder cancer is a common malignant tumor. FOXP1 has been found to be abnormally expressed in tumors such as renal cell carcinoma and endometrial cancer. Here, this investigated the biological roles of Foxp1 in the occurrence and development of bladder cancer. Patients with bladder cancer were obtained from China-Japan Friendship Hospital. Bladder cancer cell lines (5637, UMUC3, J82, and T24 cell) were used in this experiment. Foxp1 mRNA and protein expression levels in patients with bladder cancer were increased, compared with paracancerous tissue (normal). OS and DFS of Foxp1 low expression in patients with bladder cancer were higher than those of Foxp1 high expression. Foxp1 promoted bladder cancer cell growth in vitro model. Foxp1 increased the Warburg effect of bladder cancer. Foxp1 suppressed β-adrenoceptor (β-AR) expression in vitro model. ChIP-seq showed that Foxp1 binding site (E1, TTATTTAT) was detected at -2,251 bp upstream of the β-AR promoter. β-AR Reduced the effects of Foxp1 on cell growth in vitro model. β-AR reduced the effects of Foxp1 on the Warburg effect in vitro model by STAT3 activity. Taken together, our findings reveal that Foxp1 promoted the occurrence and development of bladder cancer through the Warburg effect by the activation of STAT3 activity and repressing β-AR transcription, and which might serve as an important clue for its targeting and treatment of bladder cancer.

Molecular Identification of Spatially Distinct Anabolic Responses to Mechanical Loading in Murine Cortical Bone

Osteoporosis affects over 200 million women worldwide, one-third of whom are predicted to suffer from an osteoporotic fracture in their lifetime. The most promising anabolic drugs involve administration of expensive antibodies. Because mechanical loading stimulates bone formation, our current data, using a mouse model, replicates the anabolic effects of loading in humans and may identify novel pathways amenable to oral treatment. Murine tibial compression produces axially varying deformations along the cortical bone, inducing highest strains at the mid-diaphysis and lowest at the metaphyseal shell. To test the hypothesis that load-induced transcriptomic responses at different axial locations of cortical bone would vary as a function of strain magnitude, we loaded the left tibias of 10-week-old female C57Bl/6 mice in vivo in compression, with contralateral limbs as controls. Animals were euthanized at 1, 3, or 24 hours post-loading or loaded for 1 week (n = 4-5/group). Bone marrow and cancellous bone were removed, cortical bone was segmented into the metaphyseal shell, proximal diaphysis, and mid-diaphysis, and load-induced differential gene expression and enriched biological processes were examined for the three segments. At each time point, the mid-diaphysis (highest strain) had the greatest transcriptomic response. Similarly, biological processes regulating bone formation and turnover increased earlier and to the greatest extent at the mid-diaphysis. Higher strain induced greater levels of osteoblast and osteocyte genes, whereas expression was lower in osteoclasts. Among the top differentially expressed genes at 24-hours post-loading, 17 had known functions in bone biology, of which 12 were present only in osteoblasts, 3 exclusively in osteoclasts, and 2 were present in both cell types. Based on these results, we conclude that murine tibial loading induces spatially unique transcriptomic responses correlating with strain magnitude in cortical bone. © 2022 American Society for Bone and Mineral Research (ASBMR).