Increased CK5/CK8-Positive Intermediate Cells with Stromal Smooth Muscle Cell Atrophy in the Mice Lacking Prostate Epithelial Androgen Receptor

Results from tissue recombination experiments documented well that stromal androgen receptor (AR) plays essential roles in prostate development, but epithelial AR has little roles in prostate development. Using cell specific knockout AR strategy, we generated pes-ARKO mouse with knock out of AR only in the prostate epithelial cells and demonstrated that epithelial AR might also play important roles in the development of prostate gland. We found mice lacking the prostate epithelial AR have increased apoptosis in epithelial CK8-positive luminal cells and increased proliferation in epithelial CK5-positive basal cells. The consequences of these two contrasting results could then lead to the expansion of CK5/CK8-positive intermediate cells, accompanied by stromal atrophy and impaired ductal morphogenesis. Molecular mechanism dissection found AR target gene, TGF-β1, might play important roles in this epithelial AR-to-stromal morphogenesis modulation. Collectively, these results provided novel information relevant to epithelial AR functions in epithelial-stromal interactions during the development of normal prostate, and suggested AR could also function as suppressor in selective cells within prostate

Xenogeneic cell therapy provides a novel potential therapeutic option for cancers by restoring tissue function, repairing cancer wound and reviving anti-tumor immune responses

Abstract Conventional cancer treatments such as surgery, radiotherapy, chemotherapy and targeted therapy, not only destruct tumors, but also injure the normal tissues, resulting in limited efficacy. Recent advances in cancer therapy have aimed at changing the host milieu of cancer against its development and progression by targeting tumor microenvironment and host immune system to eradicate tumors. To the host body, tumors arise in tissues. They impair the normal healthy tissue physiological function, become chronically inflamed and develop non-healing or overhealing wounds as well as drive immuno-suppressive activity to escape immunity attack. Therefore, the rational therapeutic strategies for cancers should treat both the tumors and the host body for the best efficacy to turn the deadly malignant disease to a manageable one. Xenogeneic cell therapy (i.e. cellular xenotransplantation) using cells from non-human source animals such as pigs has shown promising results in animal studies and clinical xenotransplantation in restoring lost tissue physiological function and repairing the wound. However, the major hurdle of xenogeneic cell therapy is the host immunological barriers that are induced by transplanted xenogeneic cells to reject xenografts. Possibly, the immunological barriers of xenogeneic cells could be used as immunological boosters to activate the host immune system. Here, we hypothesized that because of the biological properties of xenogeneic cells to the recipient humans, the transplantation of xenogeneic cells (i.e. cellular xenotransplantation) into cancer patients’ organs of the same origin with developed tumors may restore the impaired function of organs, repair the wound, reduce chronic inflammation and revive the anti-tumor immunity to achieve beneficial outcome for patients

Immunotherapeutic Agents for Intratumoral Immunotherapy

Immunotherapy using systemic immune checkpoint inhibitors (ICI) and chimeric antigen receptor (CAR) T cells has revolutionized cancer treatment, but it only benefits a subset of patients. Systemic immunotherapies cause severe autoimmune toxicities and cytokine storms. Immune-related adverse events (irAEs) plus the immunosuppressive tumor microenvironment (TME) have been linked to the inefficacy of systemic immunotherapy. Intratumoral immunotherapy that increases immunotherapeutic agent bioavailability inside tumors could enhance the efficacy of immunotherapies and reduce systemic toxicities. In preclinical and clinical studies, intratumoral administration of immunostimulatory agents from small molecules to xenogeneic cells has demonstrated antitumor effects not only on the injected tumors but also against noninjected lesions. Herein, we review and discuss the results of these approaches in preclinical models and clinical trials to build the landscape of intratumoral immunotherapeutic agents and we describe how they stimulate the body’s immune system to trigger antitumor immunity as well as the challenges in clinical practice. Systemic and intratumoral combination immunotherapy would make the best use of the body’s immune system to treat cancers. Combining precision medicine and immunotherapy in cancer treatment would treat both the mutated targets in tumors and the weakened body’s immune system simultaneously, exerting maximum effects of the medical intervention

Spermatogenesis and Testis Development Are Normal in Mice Lacking Testicular Orphan Nuclear Receptor 2

Early in vitro cell culture studies suggested that testicular orphan nuclear receptor 2 (TR2), a member of the nuclear receptor superfamily, may play important roles in the control of several pathways including retinoic acids, vitamin D, thyroid hormones, and ciliary neurotrophic factor. Here we report the surprising results showing that mice lacking TR2 are viable and have no serious developmental defects. Male mice lacking TR2 have functional testes, including normal sperm number and motility, and both male and female mice lacking TR2 are fertile. In heterozygous TR2(+/−) male mice we found that β-galactosidase, the indicator of TR2 protein expression, was first detected at the age of 3 weeks and its expression pattern was restricted mainly in the spermatocytes and round spermatids. These protein expression patterns were further confirmed with Northern blot analysis of TR2 mRNA expression. Together, results from TR2-knockout mice suggest that TR2 may not play essential roles in spermatogenesis and normal testis development, function, and maintenance. Alternatively, the roles of TR2 may be redundant and could be played by other close members of the nuclear receptor superfamily such as testicular orphan receptor 4 (TR4) or unidentified orphan receptors that share many similar functions with TR2. Further studies with double knockouts of both orphan nuclear receptors, TR2 and TR4, may reveal their real physiological roles

Targeted Inactivation of Testicular Nuclear Orphan Receptor 4 Delays and Disrupts Late Meiotic Prophase and Subsequent Meiotic Divisions of Spermatogenesis

Testicular orphan nuclear receptor 4 (TR4) is specifically and stage-dependently expressed in late-stage pachytene spermatocytes and round spermatids. In the developing mouse testis, the highest expression of TR4 can be detected at postnatal days 16 to 21 when the first wave of spermatogenesis progresses to late meiotic prophase. Using a knockout strategy to delete TR4 in mice, we found that sperm production in TR4(−/−) mice is reduced. The comparison of testes from developing TR4(+/+) and TR4(−/−) mice shows that spermatogenesis in TR4(−/−) mice is delayed. Analysis of the first wave of spermatogenesis shows that the delay can be due to delay and disruption of spermatogenesis at the end of late meiotic prophase and subsequent meiotic divisions. Seminiferous tubule staging shows that stages X to XII, where late meiotic prophase and meiotic divisions take place, are delayed and disrupted in TR4(−/−) mice. Histological examination of testis sections from TR4(−/−) mice shows degenerated primary spermatocytes and some necrotic tubules. Testis-specific gene analyses show that the expression of sperm 1 and cyclin A1, which are genes expressed at the end of meiotic prophase, was delayed and decreased in TR4(−/−) mouse testes. Taken together, results from TR4(+/+) and TR4(−/−) mice indicate that TR4 is essential for normal spermatogenesis in mice

Altered TNSALP Expression and Phosphate Regulation Contribute to Reduced Mineralization in Mice Lacking Androgen Receptor▿ †

While androgen receptor (AR)-deficient mice developed osteopenia in endochondral bones due to the high bone turnover with increased bone resorption by osteoclasts, little is known about the mechanism of intramembranous bone loss contributed by AR in osteoblasts. Here, we discovered a dramatic decrease in the area of calcification, new bone, and the number of osteocytes in calvaria from AR-deficient mice related to a reduction in mineralization caused, in part, by the diminished activity of AR-deficient osteoblasts. Enforced AR expression in differentiated osteoblasts boosts mineralization while knockdown of AR expression prevents androgen-induced mineralization. We identified the tissue-nonspecific alkaline phosphatase (TNSALP) and several members of small integrin binding ligand N-linked glycoprotein (SIBLING) gene family as androgen target genes required for AR-mediated bone formation. We show that inorganic phosphate (Pi) levels and TNSALP activity increased in response to androgen/AR and Pi signals increase the expression and translocation of AR. The ectopic expression of TNSALP or Pi partially rescued the bone loss due to AR deficiency. Thus, androgen/AR signaling plays an essential role in bone formation by coordinating the expression of genes associated with phosphate regulation

Reduced osteoblast activity in the mice lacking TR4 nuclear receptor leads to osteoporosis

Abstract Background Early studies suggested that TR4 nuclear receptor might play important roles in the skeletal development, yet its detailed mechanism remains unclear. Methods We generated TR4 knockout mice and compared skeletal development with their wild type littermates. Primary bone marrow cells were cultured and we assayed bone differentiation by alkaline phosphatase and alizarin red staining. Primary calvaria were cultured and osteoblastic marker genes were detected by quantitative PCR. Luciferase reporter assays, chromatin immunoprecipitation (ChIP) assays, and electrophoretic mobility shift assays (EMSA) were performed to demonstrate TR4 can directly regulate bone differentiation marker osteocalcin. Results We first found mice lacking TR4 might develop osteoporosis. We then found that osteoblast progenitor cells isolated from bone marrow of TR4 knockout mice displayed reduced osteoblast differentiation capacity and calcification. Osteoblast primary cultures from TR4 knockout mice calvaria also showed higher proliferation rates indicating lower osteoblast differentiation ability in mice after loss of TR4. Mechanism dissection found the expression of osteoblast markers genes, such as ALP, type I collagen alpha 1, osteocalcin, PTH, and PTHR was dramatically reduced in osteoblasts from TR4 knockout mice as compared to those from TR4 wild type mice. In vitro cell line studies with luciferase reporter assay, ChIP assay, and EMSA further demonstrated TR4 could bind directly to the promoter region of osteocalcin gene and induce its gene expression at the transcriptional level in a dose dependent manner. Conclusions Together, these results demonstrate TR4 may function as a novel transcriptional factor to play pathophysiological roles in maintaining normal osteoblast activity during the bone development and remodeling, and disruption of TR4 function may result in multiple skeletal abnormalities.</p