AbstractThe prognosis of advanced colorectal cancer (CRC) is currently still very poor, which suggests that the biological mechanisms of CRC oncogenesis are not fully understood. This study was conducted to explore the regulatory effect of SOX‐17 on the expression of microRNA (miR)‐302b‐3p, and the involvement of SOX‐17 in the invasion and apoptosis of CRC cells. The expression of SOX‐17 and miR‐302a,b,c,d‐3p in colorectal cancer and normal colon epithelial cell lines was measured by real‐time polymerase chain reaction and/or western blot. The regulatory effects of SOX‐17 on miR‐302b‐3p gene in HT29 and LoVo cells were tested using the ChiP assay. The biological activities of SOX‐17 and miR‐302b‐3p were evaluated by invasion and apoptosis assay. Results showed that transfection of SOX‐17 small interfering RNA (siSOX‐17) significantly increased, whereas transfection of SOX‐17 overexpression vector (oeSOX‐17) significantly decreased, miR‐302b expression in HT29 and LoVo cells. Cotransfection of oeSOX‐17 and miR‐302b‐3p inhibitor (INmiR‐302b) significantly blocked the effects of SOX‐17 in HT29 and LoVo cells. ChIP experiments showed that SOX‐17 bonded to the miR‐302b‐3p promoter in HT29 and LoVo cells. Transfection of oeSOX‐17 and miR‐302b‐3p mimics (MImiR‐302b) significantly decreased, whereas transfection of siSOX‐17 and INmiR‐302b significantly increased, the invasion of HT29 and LoVo cells. In contrast, transfection of oeSOX‐17 and MImiR‐302b significantly increased, while transfection of siSOX‐17 and INmiR‐302b significantly decreased, apoptosis in HT29 and LoVo cells. Cotransfection of oeSOX‐17 and INmiR‐302b significantly blocked the effects of oeSOX‐17 on cell invasion and apoptosis in HT29 and LoVo cells. These results suggested that SOX‐17 can bind to the promoter of miR‐302b‐3p gene to regulate its expression, while both SOX‐17 and miR‐302b regulate the invasion and apoptosis in colorectal cancer cells.

1990-05-01·European Journal of Immunology3区 · 医学

Antigen‐induced inhibition of autoimmune response to rat male accessory glands: distinct role of I‐A and I‐E‐positive peritoneal cells

3区 · 医学

Article

作者: Clelia M. Riera ; Maria Elena Ferro ; Marta Romero‐piffiguer

AbstractThe present report describes the structural and functional characteristics of the population of peritoneal cells (PC) from rats injected intraperitoneally (i.p.) 2 h or 24 h previously with a suppressor dose of a purified fraction (FI) of rat male accessory glands (RAG; FI‐PC2h and FI‐PC24h, respectively). Both populations of PC showed the presence of the autoantigens of RAG on their membrane. The study of cell surface marker showed increase of OX17 (I‐E) in FI‐PC2h and OX6 (I‐A) in FI‐PC24h. I.p. injection of FI‐PC2h 10 and 3 days prior to immunization with chemically modified (diazotized arsanilic and sulfanilic acid) RAG (MRAG) in complete Freund's adjuvant induced suppression of the delayed‐type hypersensitivity (DTH) response to MRAG, whereas the i.p. injection of FI‐PC24h induced potentiation of DTH responseto MRAG when compared with controls (animals injected 10 and 3 days prior to immunizationwith PC from rats injected i.p. with an unrelated antigen). The treatment of FI‐PC2h with OX17 and FI‐PC24h with OX6 prior to the transfer blocked the suppression and potentiation described above. These findings show that the i.p. injection of an FI of RAG at a suppressor dose induces PC with immunologically opposite characteristics, depending on the time of obtention.

1986-07-01·Cellular Immunology3区 · 医学

Antibodies against I-A and I-E determinants inhibit the activation and function of encephalitogenic T-lymphocyte lines

3区 · 医学

Article

作者: Arthur A. Vandenbark ; Steven W. Brostoff ; Halina Offner

Two monoclonal antibodies, OX-6 and OX-17, were used to evaluate respectively the roles of I-A and I-E major histocompatibility complex Class II gene products in the in vitro activation and subsequent function in recipient rats of encephalitogenic T-cell lines. Activation of the T-cell lines with guinea pig myelin basic protein (GP-BP) presented by accessory cells (APC) resulted in an increase in the number of blast cells in culture and was reflected by increased uptake of [3H]thymidine [( 3H]Tdy). The number of blasts recovered and [3H]Tdy uptake during activation was reduced drastically in the presence of OX-6, but to a much lesser extent in the presence of OX-17. OX-6 but not OX-17 appeared to block T-cell activation primarily by inhibiting APC function, since preincubation of APC but not T cells with OX-6 before stimulation resulted in complete inhibition of the cultures. After activation, the BP-1 T-cell line or D-9 clone transferred severe paralysis to normal recipient rats. Recipients of OX-6-treated BP-1 or D-9 T cells exhibited very mild or no signs, whereas recipients of OX-17-treated cells developed only slightly less severe experimental autoimmune encephalomyelitis (EAE) than recipients of untreated encephalitogenic control cultures. In contrast, treatment with OX-17 but not OX-6 reduced the ability of BP-reactive T cells to transfer delayed-type hypersensitivity reactions. Dermal testing with GP-BP in the ears of recipient rats just prior to onset of clinical signs decreased significantly the clinical intensity of EAE induced by activated BP-reactive T cells, but increased the clinical scores in rats which received unstimulated or OX-6-treated T cells. This potentiating effect of GP-BP was due most likely to the presentation of processed antigen to circulating BP-reactive T cells by APC in the ear. These results suggest that both the I-A and I-E gene products may contribute to the activation and subsequent function of encephalitogenic T cells, perhaps through separate mechanisms.

100 项与法莫替丁/奥美拉唑相关的药物交易

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