Interferon-gamma regulates the levels of bone formation effectors in a stage-dependent manner.

BACKGROUND: Interferon-gamma (IFN-γ) is an immune-derived cytokines in the innate and adaptive immune responses, and functions as a major pro-inflammatory cytokine. IFNγ has previously been reported involving in the regulation of bone metabolism. However, contradictory results about the roles of IFN-γ in bone formation or bone resorption have been reported. It is possible that the functions of IFN-γ in bone formation is dose-dependent or time-dependent. In this study we examined the effect of IFN-γ on different stages of osteoblastogenesis and bone formation. MATERIALS AND METHODS: Cell proliferation, gene expression and protein levels of the critical effectors involving in different stages of differentiation were compared between differentiating preosteoblast MC3T3-E1 treated with or without IFN-γ at different stages. Cell proliferation were determined by MTT assay. Expression levels of osteoblast differentiation markers was performed by quantitative PCR assay. Also, western blot was conducted to investigate the protein levels in those effectors. CONCLUSION: IFN-γ regulates osteoblast and bone formation in a stage-dependent manner. IFN-γ did not alter and the expression of critical osteogenic transcription factors, such as Runx2 and Cbfb, suggesting that the differentiation was not disrupted by IFN-γ. The cell number and the levels of matrix proteins, including COL1A and BSP, at both early and late stage of osteoblastogenesis were downregulated by IFN-γ, indicating its negative regulating roles in early stages. In contrast, the mineralization protein ALP and OCN was upregulated at late stages. The results suggested that IFN-γ might act as a negative regulator in osteoblast differentiation and bone formation at early stages but switch into positive regulator at late stage. Our data revealed the complex features of the effects of IFN-γ on osteoblast differentiation. The detailed mechanisms of how IFN-γ influence on the bone formation and balance of bone remodeling will be further studied.

Human ribonuclease 1 serves as a secretory ligand of ephrin A4 receptor and induces breast tumor initiation.

Human ribonuclease 1 (hRNase 1) is critical to extracellular RNA clearance and innate immunity to achieve homeostasis and host defense; however, whether it plays a role in cancer remains elusive. Here, we demonstrate that hRNase 1, independently of its ribonucleolytic activity, enriches the stem-like cell population and enhances the tumor-initiating ability of breast cancer cells. Specifically, secretory hRNase 1 binds to and activates the tyrosine kinase receptor ephrin A4 (EphA4) signaling to promote breast tumor initiation in an autocrine/paracrine manner, which is distinct from the classical EphA4-ephrin juxtacrine signaling through contact-dependent cell-cell communication. In addition, analysis of human breast tumor tissue microarrays reveals a positive correlation between hRNase 1, EphA4 activation, and stem cell marker CD133. Notably, high hRNase 1 level in plasma samples is positively associated with EphA4 activation in tumor tissues from breast cancer patients, highlighting the pathological relevance of the hRNase 1-EphA4 axis in breast cancer. The discovery of hRNase 1 as a secretory ligand of EphA4 that enhances breast cancer stemness suggests a potential treatment strategy by inactivating the hRNase 1-EphA4 axis.

Suitability of boric acid as a boron drug for boron neutron capture therapy for hepatoma.

Hepatoma is the second leading cause of cancer death worldwide. Due to the poor outcomes of patients with late diagnosis, newer treatments for hepatoma are still needed. As an emerging therapy, boron neutron capture therapy (BNCT) may be an effective solution in hepatoma management. In this study, boric acid (BA) was used as the boron drug for in vivo analysis of action mechanism. The N1S1 single liver tumor-bearing rat and the VX2 multifocal liver tumor-bearing rabbit models were used to investigate the retention status of BA in the tumor regions during BNCT. The autoradiographic examination showed BA can localize specifically not only in the hepatoma cells but also in tumor blood vessels. Our findings indicate that superior hepatoma targeting could be achieved in BA-mediated BNCT, which supports BA to be a suitable boron drug for BNCT for hepatoma.

Therapeutic Efficacy and Radiobiological Effects of Boric Acid-mediated BNCT in a VX2 Multifocal Liver Tumor-bearing Rabbit Model.

BACKGROUND/AIM: Most patients with hepatocellular carcinoma (HCC) cannot be treated using traditional therapies. Boron neutron capture therapy (BNCT) may provide a new treatment for HCC. In this study, the therapeutic efficacy and radiobiological effects of boric acid (BA)-mediated BNCT in a VX2 multifocal liver tumor-bearing rabbit model are investigated. MATERIALS AND METHODS: Rabbits were irradiated with neutrons at the Tsing Hua Open Pool Reactor 35 min following an intravenous injection of BA (50 mg 10B/kg BW). The tumor size following BNCT treatment was determined by ultrasonography. The radiobiological effects were identified by histopathological examination. RESULTS: A total of 92.85% of the tumors became undetectable in the rabbits after two fractions of BNCT treatment. The tumor cells were selectively eliminated and the tumor vasculature was collapsed and destroyed after two fractions of BA-mediated BNCT, and no injury to the hepatocytes or blood vessels was observed in the adjacent normal liver regions. CONCLUSION: Liver tumors can be cured by BA-mediated BNCT in the rabbit model of a VX2 multifocal liver tumor. BA-mediated BNCT may be a breakthrough therapy for hepatocellular carcinoma.

Rab5A is associated with axillary lymph node metastasis in breast cancer patients.

The expression of Rab proteins has been associated with cancer. However, few data are available on Rab5A expression in human breast cancer or its impact on disease progression. First, we examined the functional role of Rab5A in breast cancer cells. The expression of Rab5A in MDA-MB-231 cells can be stimulated by epidermal growth factor in a dose-dependent manner. The epidermal growth factor-induced increase of Rab5A expression correlated well with enhanced migration in wound healing migration assays in these cells. Furthermore, we evaluated the expression of Rab5A in breast cancer specimens using immunohistochemical staining, then analyzed the relationship between the expression of Rab5A and clinicopathological parameters. The increased expression of Rab5A protein in 123 breast cancer samples was associated with higher histological grade (P = 0.004), more lymphovascular invasion (P = 0.027), more axillary lymph node (LN) metastasis (P = 0.008), and a higher number of axillary LN metastases (P = 0.043). Among 218 axillary LNs of more than 10 breast cancer patients with node metastases, 167 metastatic LNs were found to have increased Rab5A expression. Rab5A is associated with axillary LN metastasis in breast cancer patients.

Treatment of massive retroperitoneal hemorrhage from adrenal metastasis of hepatoma.

Spontaneous rupture of metastatic adrenal tumor with massive retroperitoneal hemorrhage and shock is an uncommon clinical event. Herein, we report a case of hepatocellular carcinoma (HCC), where left hepatic lobectomy and right adrenalectomy for metastatic HCC were performed in April and August 2002, respectively. Subsequently, the patient presented to the emergency room with acute-onset severe left flank and back pain in March 2004, accompanied by a falling hemoglobin level. Computed tomography revealed a 7-cm left adrenal tumor mass with retroperitoneal hemorrhage. The ruptured adrenal tumor was further confirmed by selective angiography, which demonstrated that the bleeder was supplied by the left suprarenal artery. Transarterial embolization (TAE) to stop tumor bleeding was performed successfully. The patient then underwent tumor resection with left adrenalectomy 5 days after the embolization, with pathology subsequently revealing metastatic HCC. The recurrent intrahepatic HCC was controlled with TAE, and the patient underwent hormone replacement therapy with prednisolone 10 mg/day. Metastatic adrenal tumor bleeding should be suspected in hepatoma patients who suffer abrupt flank pain and shock. Hemodynamically unstable patients require supportive transfusions and urgent surgical exploration. Angiographic embolization, if deemed feasible, may be a valuable adjunct for achievement of hemostasis prior to definite surgery.