PPARγ2 functions as a tumor suppressor in a translational mouse model of human prostate cancer.

Peroxisome proliferator-activated receptors γ (PPARγ) is a master regulator that controls energy metabolism and cell fate. PPARγ2, a PPARγ isoform, is highly expressed in the normal prostate but expressed at lower levels in prostate cancer tissues. In the present study, PC3 and LNCaP cells were used to examine the benefits of restoring PPARγ2 activity. PPARγ2 was overexpressed in PC3 and LNCaP cells, and cell proliferation and migration were detected. Hematoxylin and eosin (H&E) staining was used to detect pathological changes. The genes regulated by PPARγ2 overexpression were detected by microarray analysis. The restoration of PPARγ2 in PC3 and LNCaP cells inhibited cell proliferation and migration. PC3-PPARγ2 tissue recombinants showed necrosis in cancerous regions and leukocyte infiltration in the surrounding stroma by H&E staining. We found higher mixed lineage kinase domain-like (MLKL) and lower microtubule-associated protein 1 light chain 3 (LC3) expression in cancer tissues compared to controls by immunohistochemistry (IHC) staining. Microarray analysis showed that PPARγ2 gain of function in PC3 cells resulted in the reprogramming of lipid- and energy metabolism-associated signaling pathways. These data indicate that PPARγ2 exerts a crucial tumor-suppressive effect by triggering necrosis and an inflammatory reaction in human prostate cancer.

Protection of seven dibenzocyclooctadiene lignans from Schisandra chinensis against serum and glucose deprivation injury in SH-SY5Y cells.

Dibenzocyclooctadiene lignans, the major active components of fruit of Schisandra chinensis (Turcz.) Baill., have been found to have activities that could prevent prostate and thyroid cancer, hepatotoxicity, oxidative stress-induced cerebral injury, etc. This study was conducted to evaluate the effects of seven dibenzocyclooctadiene lignans of Schisandra chinensis and explore the possible mechanisms in the human neuroblastoma SH-SY5Y cells exposed on serum and glucose deprivation (SGD) injury. The structure-activity relationships were also analyzed. Cell viability and lactate dehydrogenase (LDH) release were determined to evaluate cell injury. Inflammation and apoptosis-related protein levels were detected to elucidate the possible mechanisms. Schisantherin A, schizandrin C, and schizandrol B were found to have stronger protective effects than schizandrin A, schizandrin B, and schisanhenol in SH-SY5Y cells against SGD injury. Moreover, the protective effects of these lignans were possibly exhibited by regulating inflammation and apoptosis-related proteins in SH-SY5Y cells after SGD injury, supporting their beneficial effects for the prevention of cell injury in the pathogenesis of the central nervous system diseases, including ischemia stroke. The number and position of hydroxyl group and methylenedioxy in these lignans may be required for their effects.

The expression of beclin-1, an autophagic gene, in hepatocellular carcinoma associated with clinical pathological and prognostic significance.

BACKGROUND: A role for autophagy, a conserved cellular response to stress, has recently been demonstrated in human cancers. Aberrant expression of Beclin-1, an important autophagic gene, has been reported in various human cancers. In the present study, we investigated the significance and relationship between Beclin-1 expression and cell proliferation, apoptosis, microvessel density (MVD) and clinical pathological changes or prognosis in human hepatocellular carcinoma (HCC). METHODS: A total of 103 primary HCC patients were involved in the study. Expression of Beclin-1, PCNA, NET-1, Bcl-2, Bax, Survivin in cancer cells and CD34 in stromal microvessels were evaluated immunohistochemically in tissue microarrays comprising 103 cases of HCC and 57 matched adjacent nontumor liver tissues. Correlations between clinicopathological characteristics and survival of HCC patients were explored. RESULTS: The positive rate of Beclin-1 was significantly lower in HCC tissues than adjacent tissues (72.8 vs. 89.5%, χ2 = 6.085, P = 0.015). In HCC, Beclin-1 expression was negatively correlated with cirrhosis background (r = -0.216, P = 0.029), Edmondson grade (r = -0.249, P = 0.011), vascular invasion (r = -0.246, P = 0.012), PCNA (r = -0.242, P = 0.014), NET-1 (r = -0.245, P = 0.013), anti-apoptosis protein Bcl-2 (r = -0.245, P = 0.013) and MVD (r = -0.292, P = 0.003), and positively correlated with pro-apoptosis protein Bax (r = 0.242, P = 0.014).Significant differences in the 5-year survival rates were seen among patients with Beclin-1 strong positive (++) (59.1%, 13/22), moderate positive (+) (28.3%, 15/53) and weak negative expression (-) (14.6%, 7/28) (P = 0.043). Significant differences were detected between Beclin-1 (++) and either Beclin-1 (+) (P = 0.036) or Beclin-1 (-) groups (P = 0.008), but no significant difference between Beclin-1 (+) and Beclin-1 (-) groups (P = 0.281) was observed.Survival rates were positively related to high Beclin-1 co-expressed with low PCNA, NET-1, or Bcl-2, lower MVD, and high Bax. Univariate and multivariate Cox regression analysis revealed that Beclin-1 expression was an independent indicator for overall survival in HCC patients (P < 0.05). CONCLUSIONS: The pathogenesis and progression of HCC are associated with reduced autophagy. The expression of Beclin-1 and Bax in HCC tissues may provide a synergistic effect towards inhibiting HCC proliferation, infiltration, metastasis and angiogenesis. Beclin-1 expression may be a valuable prognostic marker of HCC.

Comparison of the expression of 5 heat shock proteins in benign and malignant salivary gland tumor tissues.

The objective of this study was to analyze the significance and potential value of heat shock proteins (HSPs) in salivary gland tumors. We found that expression of HSP60, HSP70, HSP86 and HSP84 were all upregulated in both salivary gland benign tumors and malignant tumors, and that the expression of HSP70, HSP86 and HSP84 was more greatly overexpressed in the malignant tumors (each P<0.01). For HSP27, expression was upregulated both in malignant and benign tumors, with less expression observed in malignant tumors (P<0.01). In malignant tumors, expression of HSP27 was negatively correlated with the age of the patients, size of the tumor tissue, occurrence of neural invasion and metastasis (each P<0.05). Additionally, in malignant tumors, HSP70 and HSP86 were both positively correlated with occurrence site, neural invasion and metastasis (each P<0.05), while HSP60 was only negatively correlated with the age of the patients (P<0.05). HSP86 was also positively correlated with malignant degree (P<0.01). In malignant tumors, the proliferation index (PI), which was marked by proliferating cell nuclear antigen (PCNA; PCNA-PI) was 49.95±14.569, which was significantly higher compared with that in benign tumors (P<0.001), which was in accordance with the upregulation of HSP70, HSP86 or HSP84; however, an adverse correlation was found between HSP27 expression and PCNA (each P<0.05). In conclusion, these results suggest that HSPs are involved in the occurrence and development of salivary gland tumors. HSP70, HSP86 and HSP84 retained the higher multiplication capability of the malignant tumor cells, however, HSP27 did not. Thus, the upregulation of HSP70, HSP86 and HSP84 and the downregulation of HSP27 may all be used as biomarkers of the occurrence and development of malignant salivary gland tumors. Moreover, the extremely high expression of HSP86 and HSP84 in benign tumors indicates the malignant transformation potential.

TLR3 dsRNA agonist inhibits growth and invasion of HepG2.2.15 HCC cells.

Toll-like receptor 3 (TLR3) is a pattern-recognizing receptor that is involved in immune signaling and plays a crucial role in survival by being able to recognize various viral components including double-stranded RNA (dsRNA). TLR3 expression and function in cancer cells are not well understood. In this study, we investigated whether TLR3 agonist dsRNA (BM-06) can inhibit proliferation and invasion, and promote apoptosis in HepG2.2.15 cells. HepG2.2.15 cells secreting hepatitis B virus (HBV) were treated with BM-06 and poly(I:C). Western blot analysis and PCR were employed to determine pharmacodynamic changes in biomarkers relevant to TLR3 signaling. Cell proliferation, invasion and apoptosis were analyzed by CCK-8 assay, transwell assay and flow cytometry. The expression of HBsAg, and HBcAg was observed by immunohistochemistry. Compared with untreated cells, pharmacological NF-κB activity of the TLR3 pathway by BM-06 (1.734-fold) or poly(I:C) (1.377-fold) was induced. By western blot analysis, we found that dsRNA induced TLR3-activated HepG2.2.15 cells which expressed NF-κB levels predominantly in the cytoplasmic fraction but fewer signals in the nucleus. BM-06 inhibited the proliferation, invasion and secretion of HBV, and induced apoptosis in HepG2.2.15 cells. In addition, the antitumor effects of BM-06 were superior to poly(I:C). Pharmacological activation of the TLR3 pathway by BM-06 can inhibit HepG2.2.15 cell growth.

Comparative proteomic analysis of rat hepatic stellate cell activation: a comprehensive view and suppressed immune response.

UNLABELLED: Elucidation of the molecular events underlying hepatic stellate cell (HSC) activation is an essential step toward understanding the biological properties of HSC and clarifying the potential roles of HSCs in liver fibrosis and other liver diseases, including hepatocellular carcinoma. High-throughput comparative proteomic analysis based on isobaric tags for relative and absolute quantitation (iTRAQ) labeling combined with online two-dimensional nanoscale liquid chromatography and tandem mass spectrometry (2D nano-LC-MS/MS) were performed on an in vitro HSC activation model to obtain a comprehensive view of the protein ensembles associated with HSC activation. In total, 2,417 proteins were confidently identified (false discovery rate <1%), of which 2,322 proteins were quantified. Compared with quiescent HSCs, 519 proteins showed significant differences in activated HSCs (≥ 3.0-fold). Bioinformatics analyses using Ingenuity Pathway Analysis revealed that the 319 up-regulated proteins represented multiple cellular functions closely associated with HSC activation, such as extracellular matrix synthesis and proliferation. In addition to the well-known markers for HSC activation, such as α-smooth muscle actin and collagen types 1 and 3, some novel proteins potentially associated with HSC activation were identified, while the 200 down-regulated proteins were primarily related to immune response and lipid metabolism. Most intriguingly, the top biological function, top network, and top canonical pathway of down-regulated proteins were all involved in immune responses. The expression and/or biological function of a set of proteins were properly validated, especially Bcl2-associated athanogene 2, BAG3, and B7H3. CONCLUSION: The present study provided the most comprehensive proteome profile of rat HSCs and some novel insights into HSC activation, especially the suppressed immune response.

[Expression of nuclear export factor CRM1 and p27 in glioma].

OBJECTIVE: To investigate the expression of nuclear export factor CRM1, Ser10-phosphorylated p27 and p27 in human gliomas. METHODS: The expression of CRM1, Ser10-phosphorylated p27 and p27 were investigated in 70 cases of human gliomas and 10 specimens of the normal brain tissue by immunohistochemical technique and Western blot. RESULTS: There were significant differences on the expression levels of CRM1, Ser10-phosphorylated p27 and p27 among normal brain tissue, gliomas of grades II and gliomas of grades III plus IV (P < 0.01). The expression of CRM1 in gliomas was inversely correlated with the expression of p27 (r(s) = -0.727, P < 0.01) and positively correlated with the expression of Ser10-phosphorylated p27 (r(s) = 0.954, P < 0.01) and Ki-67 (r(s) = 0.799, P < 0.01). Moreover, the expression of Ser10-phosphorylated p27 was inversely correlated with p27 (r(s) = -0.744, P < 0.01) and positively correlated with Ki-67 (r(s) = 0.785, P < 0.01). CONCLUSIONS: CRM1, through recognizing and binding with Ser10-phosphorylated p27, may promote moving of p27CRM1 from its original locating sites; act as a critical signaling component in the proliferative process of glioma cells and then, plays an important role in the development of gliomas.