OBJECTIVETo study the expression and clinical significance of ribosomal S6 kinase-4 (RSK-4) in breast cancer and explore the role of RSK-4 in the genesis and development of breast cancer.

METHODThe expression levels of RSK-4 mRNA and protein were detected in 56 cases of breast cancer and the normal breast tissues, as well as in 20 cases of breast benign lesions, by reverse transcriptase polymerase chain reaction (RT-PCR) and immunohistochemistry.

RESULTSThe expression rates of RSK-4 mRNA in breast cancer, the normal breast tissues and breast benign lesions were 48.2%, 76.8% and 75.0%, respectively. The expression level of RSK-4 mRNA in breast cancer was significantly lower than those in normal breast tissues and breast benign lesions tissues (P < 0.05). The expression level of RSK-4 significantly correlated with tumor size and clinical stage (P < 0.05).The expression rate of RSK-4 protein was 39.3% in breast cancer tissues, which was significantly lower than that of normal breast tissues (71.4%) and breast benign lesions (75.0%, P < 0.01). The expression level of RSK-4 protein was lower in breast cancer with large tumor, high clinical stage and lymph node metastasis. In 56 cases of breast cancer samples, the consistency rate of RSK-4 mRNA and protein was 73.2%. A significant correlation was found between RSK-4 mRNA and protein (χ² = 10.254, P < 0.05).

CONCLUSIONThe down-regulation of RSK-4 expression in breast caner suggests that it is a breast cancer suppressor gene, and the lack or down-regulation of RSK-4 expression is involved in the genesis and progression of breast cancer.

Adult ; Aged ; Breast ; metabolism ; Breast Neoplasms ; metabolism ; pathology ; Carcinoma, Ductal, Breast ; metabolism ; pathology ; Down-Regulation ; Female ; Fibroadenoma ; metabolism ; pathology ; Humans ; Lymphatic Metastasis ; Middle Aged ; Neoplasm Staging ; RNA, Messenger ; metabolism ; Ribosomal Protein S6 Kinases, 90-kDa ; genetics ; metabolism ; Tumor Burden ; Young Adult

Objective:To explore the effect of natural decay of exogenously added fibrous roots on the growth and development of Paris polyphylla var. yunnanensis and its medicinal quality. Method:The effects of natural decay of fibrous roots at different amounts on mycorrhizal infection rate， physiological and biochemical indexes， and saponin contents of P. polyphylla var. yunnanensis were studied in pot culture experiments at room temperature. Result:The results showed that the infection rate of arbuscular mycorrhizal （AM） fungi in the root of P. polyphylla var. yunnanensis was not significantly affected by different fibrous root treatments， but there were significant differences in infection intensity. The photosynthetic pigment content in the leaves declined significantly with the increase in fibrous root amount， and the total chlorophyll was decreased by 78.7% at most. The contents of soluble protein， soluble sugar and malondialdehyde in the leaves of P. polyphylla var. yunnanensis showed an overall upward trend. The activities of the three protective enzymes varied. The peroxidase and malondialdehyde were reduced by 181.6% and 200.0% at most. In the root system of P. polyphylla var. yunnanensis， the contents of the above-mentioned six components decreased to varying degrees， with the largest reductions of peroxidase and malondialdehyde reaching 44.6% and 69.7%. Different fibrous root treatments resulted in a decrease in active component content of P. polyphylla var. yunnanensis. The total content of the four saponins was decreased by 58.9% at most， and the total saponin content by 46.9%. Conclusion:The natural decay of fibrous roots affects the soil microbial environment of root system， reduces the photosynthetic pigment content in leaves， and destroys the stability of cells， thus interfering with the growth and development of P. polyphylla var. yunnanensis， reducing its medicinal components， and causing continuous cropping obstacles.

OBJECTIVETo evaluate whether mono (2-ethylhexyl) phthalate (MEHP) affects genomic DNA methylation and the methylation status of some specific genes such as patched gene (PTCH) and smoothened gene (SMO) in LNCaP cells.

METHODSLNCaP cells were treated with MEHP (0, 1, 5, 10, and 25 μmol/L) for 3 days. An ELISA assay was preformed to detect genomic methylation, including 5-methylcytosine (5-mC) and 5-hydroxymethylcytosine (5-hmC) content. A pyrosequencing assay was applied to assess DNA methylation in PTCH and SMO gene promoters. The correlation between DNA methylation and gene expression was assessed.

RESULTSThe proportion of cytosines with 5-mC methylation in LNCaP cells was significantly decreased by MEHP (1, 5, 10, and 25 μmol/L) in a dose-dependent manner (P < 0.01). For genes in the Hedgehog pathway, there was no significant MEHP concentration-dependent difference in the DNA methylation of PTCH and SMO.

CONCLUSIONMEHP might affect the progression of prostate cancer through its effect on global DNA methylation.

Antineoplastic Agents ; chemistry ; pharmacology ; Cell Line, Tumor ; DNA Methylation ; Humans ; Male ; Phthalic Acids ; chemistry ; Prostatic Neoplasms ; metabolism