Background and purpose:Spleen Tyrosine Kinase(Syk) may play a significant role in tumor signal transduction.Some studies showed that Syk was an anti-oncogene against oncogene Her-2.We investigated the impact of Syk expression on metastasis and apoptosis of gastric cancer cells in order to explore the new target therapy for the treatment of gastric carcinoma.Methods:Expression of Syk was evaluated by RT-PCR in 44 human gastric cancer tissues and adjacent normal gastric tissue samples,and apoptosis index in gastric carcinoma was detected by flow cytometry.The relationship between apoptosis index in gastric carcinoma and Syk expression was analyzed.Results:All normal gastric tissues demonstrated expression of the Syk gene,while 34 out of 44 gastric cancer tissues did not show any detectable Syk mRNA expression,there was a significant difference between the two groups(?2=9.14,P

Objective:To investigate the effect of CCN1 on the chemosensitivity of colon cancer cells to 5-FU .Methods:Colon cancer and adjacent tissues, colon cancer cells and normal colon epithelial cells, HCT-116 and HCT-116/5/FU cells were collected, and the SCD1 mRNA expression levels were detected by RT-qPCR; HCT-116 cells were cultured and transfected with pcDNA3.1 and CCN1 expression vectors, or infected with shNC and shCCN1 lentivirus, CCK-8 assay was used to detect cell sensitivity to 5-FU, Western blot and RT-qPCR were used to detect SCD1 mRNA expression, and oil red O staining was used to detect the lipid content. Western blot was used to detect the distribution of transcription factor FoxO1 in the nucleus and cytoplasm. The effect of CCN1 and FoxO1 on the transcriptional activity of SCD1 promoter was detected by luciferase assay.Results:Compared with control group, the expression of SCD1 was up-regulated in colon cancer tissues, cell lines and HCT-116/5-FU cells (all P<0.05); overexpression of CCN1 reduced the sensitivity to 5-FU, increased intracellular lipid deposition, and up-regulated the expression of SCD1 ( P<0.05); Knockdown of CCN1 increased the sensitivity to 5-FU, reduced intracellular lipid content and down-regulate the expression level of SCD1 ( P<0.05); CCN1 can promote FoxO1 nuclear distribution, activation or inhibition of FoxO1 activity can promote or up-regulate SCD1 expression level and promoter activity ( P<0.05). Conclusion:CCN1 may up-regulate the expression of SCD1 by activating FoxO1 activity and inhibit the sensitivity of colon cancer cells to 5-FU.

Objective To explore the sensitivity of HER-2-positive BT474 breast cancer cells to trastuzumab after knockdown or overexpression of RNA binding protein 38 ( RNPC1 ) .Methods The expressions of RNPC1 and HER-2 mRNA were detected by qRT-PCR, and the expressions of RNPC1, HER-2 and PI3K/AKT proteins were detected by Western blot after transfected with RNPC1 lentiviral vector, respectively.The experimental groups were treated with different concentration of trastuzumab, and cell apoptosis rate was analyzed by 7-AAD/APC double staining flow cytometry, and cell growth inhibition rate was tested by cell counting kit 8 ( CCK-8) .The expression of apoptosis-related proteins was detected by Western blot assay.Results The results of qRT-PCR showed that overexpression of RNPC1 increased the expressions of RNPC1 and HER-2 mRNA, and the expressions of RNPC1 and HER-2 were decreased after RNPC1 knockdown.The knockdown of RNPC1 decreased the expressions of RNPC1 and HER-2.Moreover, overexpression of RNPC1 decreased and knockdown of RNPC1 increased the levels of p-PI3K and p-AKT while the total protein expressions of both were marginally changed.The results of analysis using a cell counting CCK-8 kit showed that the RNPC1 overexpressed group had a higher growth inhibition rate [(20.33± 1.25)%,(35.38±2.05)%,(50.43±2.12)%,(65 .35±2.08)%and(76.00±2.16)%, respectively] than that of the control group [(13.67±1.24)%,(27.86±2.05)%,( 39.72±1.69)%,(53.33±1.70)%and(62.68± 2.07)%] when treated with different concentrations of trastuzumab (5, 10, 15, 20 and 25 μg/ml).The cell apoptosis rates in the RNPC1-overexpressed group [ ( 19.46 ±1.06 )%, ( 30.87 ±0.98 )%, ( 50.45 ± 1.1)3%, respectively] were also increased compared with that in the control group [(14.38±0 .64)%,(21.65± 1.24)%,(38.03±0.85)%] when treated with different concentrations of trastuzumab (0, 10, 20 and 30μg/ml) ( P<0.05 for all).Reverse results were observed in the RNPC1 knockdown experiments [ experimental groups:(9.67±1.18)%, ( 21.67 ±1.23)%, ( 30.33 ±1.25)%, ( 40.33 ±1.69)%, and ( 53.00 ± 1.63)%] compared with those of control groups:[(14.00±0.82)%, (27.67±1.25)%, (39.67±1.79)%, (53.67±1.50)%, and (63.33±1.52)%];and experimental groups:[(11.64±0.68)%, (16.60±1.01)%, and (25.14±3.12)%] compared with those of the control groups: [(14.71±0.61)%, (22.65±0.96)%, and (39.03±0.85)%].The overexpression of RNPC1 increased the expression levels of Bim and Bad and decreased the level of Bcl-xl, and reverse result was observed after knockdown of RNPC1.Conclusion RNPC1 may promote the sensitivity of breast cancer cells to trastuzumab through the increased expression of HER-2 in the BT474 breast cancer cells.

Objective To investigate the regulatory mechanism of RNA binding motif protein 38 (RNPC1) on the expression of progesterone receptor (PR) in breast cancer cell line ZR?75?1. Methods Lentiviral vector was used to induce overexpression of RNPC1 in ZR?75?1 cells. qRT?PCR and Western blot were used to assess the regulatory effect of RNPC1 on PR expression. Actinomycin was used to detect the regulatory mechanism involved. Immunohistochemical ( IHC) staining was used to determine the protein expression of RNPC1 and PR in 80 breast cancer tissues. Results IHC staining showed that the expression of RNPC1 was significantly higher in the PR positive breast cancer tissues than that in the PR negative breast cancer tissues ( P<0.05) . The qRT?PCR results showed that overexpression of RNPC1 in ZR?75?1 cells significantly upregulated the mRNA level of PR (1.764±0.028 vs. 1.001±0.037, P<0.01), whereas knockdown of RNPC1 did the opposite (0.579± 0.007 vs. 1.000±0.002, P<0.01).The Western blot results also showed that overexpression of RNPC1 up?regulated PR levels, while knockdown of RNPC1 resulted in down?regulation of PR levels in the ZR?75?1 cells. The actinomycin assay showed that overexpression of RNPC1 increased the mRNA stability of PR. The half?life of PR mRNA was increased from 4. 0 h to 6. 5 h. Knockdown of RNPC1 decreased the mRNA stability of PR and the half?life of PR transcript was decreased from 4.1 h to 3.0 h. Conclusion RNPC1 plays a crucial role in regulating the expression of PR in breast cancer ZR?75?1 cells.

Objective To explore the sensitivity of HER-2-positive BT474 breast cancer cells to trastuzumab after knockdown or overexpression of RNA binding protein 38 ( RNPC1 ) .Methods The expressions of RNPC1 and HER-2 mRNA were detected by qRT-PCR, and the expressions of RNPC1, HER-2 and PI3K/AKT proteins were detected by Western blot after transfected with RNPC1 lentiviral vector, respectively.The experimental groups were treated with different concentration of trastuzumab, and cell apoptosis rate was analyzed by 7-AAD/APC double staining flow cytometry, and cell growth inhibition rate was tested by cell counting kit 8 ( CCK-8) .The expression of apoptosis-related proteins was detected by Western blot assay.Results The results of qRT-PCR showed that overexpression of RNPC1 increased the expressions of RNPC1 and HER-2 mRNA, and the expressions of RNPC1 and HER-2 were decreased after RNPC1 knockdown.The knockdown of RNPC1 decreased the expressions of RNPC1 and HER-2.Moreover, overexpression of RNPC1 decreased and knockdown of RNPC1 increased the levels of p-PI3K and p-AKT while the total protein expressions of both were marginally changed.The results of analysis using a cell counting CCK-8 kit showed that the RNPC1 overexpressed group had a higher growth inhibition rate [(20.33± 1.25)%,(35.38±2.05)%,(50.43±2.12)%,(65 .35±2.08)%and(76.00±2.16)%, respectively] than that of the control group [(13.67±1.24)%,(27.86±2.05)%,( 39.72±1.69)%,(53.33±1.70)%and(62.68± 2.07)%] when treated with different concentrations of trastuzumab (5, 10, 15, 20 and 25 μg/ml).The cell apoptosis rates in the RNPC1-overexpressed group [ ( 19.46 ±1.06 )%, ( 30.87 ±0.98 )%, ( 50.45 ± 1.1)3%, respectively] were also increased compared with that in the control group [(14.38±0 .64)%,(21.65± 1.24)%,(38.03±0.85)%] when treated with different concentrations of trastuzumab (0, 10, 20 and 30μg/ml) ( P<0.05 for all).Reverse results were observed in the RNPC1 knockdown experiments [ experimental groups:(9.67±1.18)%, ( 21.67 ±1.23)%, ( 30.33 ±1.25)%, ( 40.33 ±1.69)%, and ( 53.00 ± 1.63)%] compared with those of control groups:[(14.00±0.82)%, (27.67±1.25)%, (39.67±1.79)%, (53.67±1.50)%, and (63.33±1.52)%];and experimental groups:[(11.64±0.68)%, (16.60±1.01)%, and (25.14±3.12)%] compared with those of the control groups: [(14.71±0.61)%, (22.65±0.96)%, and (39.03±0.85)%].The overexpression of RNPC1 increased the expression levels of Bim and Bad and decreased the level of Bcl-xl, and reverse result was observed after knockdown of RNPC1.Conclusion RNPC1 may promote the sensitivity of breast cancer cells to trastuzumab through the increased expression of HER-2 in the BT474 breast cancer cells.

Objective To investigate the regulatory mechanism of RNA binding motif protein 38 (RNPC1) on the expression of progesterone receptor (PR) in breast cancer cell line ZR?75?1. Methods Lentiviral vector was used to induce overexpression of RNPC1 in ZR?75?1 cells. qRT?PCR and Western blot were used to assess the regulatory effect of RNPC1 on PR expression. Actinomycin was used to detect the regulatory mechanism involved. Immunohistochemical ( IHC) staining was used to determine the protein expression of RNPC1 and PR in 80 breast cancer tissues. Results IHC staining showed that the expression of RNPC1 was significantly higher in the PR positive breast cancer tissues than that in the PR negative breast cancer tissues ( P<0.05) . The qRT?PCR results showed that overexpression of RNPC1 in ZR?75?1 cells significantly upregulated the mRNA level of PR (1.764±0.028 vs. 1.001±0.037, P<0.01), whereas knockdown of RNPC1 did the opposite (0.579± 0.007 vs. 1.000±0.002, P<0.01).The Western blot results also showed that overexpression of RNPC1 up?regulated PR levels, while knockdown of RNPC1 resulted in down?regulation of PR levels in the ZR?75?1 cells. The actinomycin assay showed that overexpression of RNPC1 increased the mRNA stability of PR. The half?life of PR mRNA was increased from 4. 0 h to 6. 5 h. Knockdown of RNPC1 decreased the mRNA stability of PR and the half?life of PR transcript was decreased from 4.1 h to 3.0 h. Conclusion RNPC1 plays a crucial role in regulating the expression of PR in breast cancer ZR?75?1 cells.