Effects Of Receptor Interacting Protein Research Articles

Expression of receptor interacting protein 2 in colorectal cancer and its relationship with invasion and metastasis of tumors

Objective To explore the effect of receptor interacting protein 2 (RIP2) in invasion and migration of colorectal cancer (CRC), expression of RIP2 in CRC was tested, and variety was observed after RIP2 was inhibited in CRC cell line. Methods Sixty-eight cases of CRC paraffin-embedded specimens and 50 cases of tumor-adjacent tissues were collected, and the expression of RIP2, matrix metalloproteinase (MMP)-2 and MMP-9 was detected by immunohistochemistry (IHC), then clinicopathological parameters of patients were also recorded. The relationship among 3 proteins was also evaluated. RNA interference (RNAi) technology was employed to inhibit the RIP2 in HT29 cells, and variety of invasion and migration was tested in HT29 cells. Results It was showed that positive expressions of RIP2 (67.65%) was higher in CRC tumors than in tumor-adjacent tissues (28.00%) (χ2=4.819, P<0.01). Expression of RIP2 was correlated with tumor invasion depth, lymph node metastasis (χ2=4.390, P<0.05; χ2=5.569, P<0.05). There was positive relationship between RIP2 and MMP-2, RIP2 and MMP-9 (r=0.326, P<0.01; r=0.439, P<0.01). After RIP2 inhibition, migration ability of HT29 cells weakened (F=36.471, P<0.01), and expressions of MMP-2, MMP-9 decreased simultaneously (F=9.090, P<0.05; F=5.732, P<0.05). Conclusion RIP2 was up-regulated in CRC tissues, and RIP2 may promote invasion and metastasis of CRC by regulating MMP-2, MMP-9. Key words: Colorectal cancer; Receptor interacting protein 2; Gene interference; Invasion; Metastasis

Effect of interleukin-17 on receptor-interacting protein 4 expression and keratinocyte proliferation.

The aim of the present study was to investigate the effect of receptor-interacting protein 4 (RIP4) on keratinocyte proliferation and its role in the pathogenesis of psoriasis vulgaris. The expression of RIP4 and Ki-67 in fixed sections from 30 patients with psoriasis vulgaris and 30 gender- and age-matched healthy controls was detected by two-step immunohistochemistry, prior to the correlation being examined with Pearson's analysis. Reverse transcription-semi-quantitative polymerase chain reaction and western blot analyses were carried out to detect the mRNA and protein expression of RIP4 in an immortalized human keratinocyte line, HaCaT, stimulated by different concentrations of interleukin-17 (IL-17), in order to analyze the change in RIP4 expression following IL-17 stimulation. The cell proliferation rate was measured using the cell counting kit-8 assay simultaneously. RIP4 was mainly present in the cytoplasm of the keratinocytes. Compared with its expression in the healthy control skin, RIP4 exhibited a significant upregulation in the psoriatic lesions (P<0.05). Pearson's correlation analysis revealed a positive correlation between the expression level of RIP4 and the proliferation index. Both RIP4 mRNA and protein levels were significantly increased following IL-17 stimulation. Exposure to IL-17 additionally increased the proliferation rate of the HaCaT cells. In conclusion, RIP4 may play a role in the pathogenesis of psoriasis vulgaris as a potential target of IL-17.

The effects of Receptor Interacting Protein 3 on necroptosis in RGC‐5 following elevated hydrostatic pressure

ObjectiveRIP3 has been found to induce necroptosis. Previous study have demonstrate necroptosis is an important neuronal death mode in retinal ischemia, and RIP3 may relate to necrosis in our observation. The lack of RIP3 inhibitor limited our study in vivo, so we first identify necroptosis in RGC‐5 following EHP, and then detect the protein level of RIP3, the percentage of necrosis using the pressure chamber via rip3 RNAi. Finally, we try to elaborate the mechanism of necroptosis.MethodsAfter 6 hr, 12 hr, 24 hr of recovery, we execute PI‐staining with different pressure values insults, then detected the level of RIP3 expression and the number of necrosis cells using western‐blotting, fluorescence‐staining. We analyzed the percentage of necrosis in 24 hr to identify the existence of necroptosis within necrostatin‐1. Finally rip3‐RNAi were carried out to get the converse evidence on necroptosis.ResultsPI‐staining in different pressure levels showed there was little necrosis cell under 60 mmHg and the percentage of cell necrosis increased following the pressure elevation. As pressure level elevated, the number of necrosis cells increased too. RIP3 expression was up‐regulated and there exist double‐labeling of some RIP3 enhance‐labeled and PI‐positives after 6 hr. The results of flow cytometry indicated the ratio of necrosis cells were decreased from 13% to 5% within necrostatin‐1, the percentage of necrosis cells decreased to nearly 7% using rip3‐RNAi.ConclusionRIP3 may participate in necroptosis following EHP.This work was supported by National Natural Science Foundation of China (81371011),Wu Jie‐Ping Medical Foundation of the Minister of Health of China (320.6750.14118), Natural Science Foundation of Hunan Province (2015JJ2187)

Effects of receptor-interacting protein 140 gene over-expression on the migration and proliferation of neuroblastoma cells

To explore the effects of receptor interacting protein (RIP)140 gene over-expression upon the migration and proliferation of neuroblastoma cells in vitro. The N2a RIP140 over-expression model (N2a-rip140) was constructed by lipofection and validated by real-time polymerase chain reaction (PCR) and Western blot. The migration and proliferation capabilities were compared between N2a-rip140 and its parents by Transwell chamber and CCK-8. The N2a RIP140 over-expression model (N2a-rip140) was successfully constructed. Compared to N2a group, the RIP140 mRNA and protein expression levels of N2a-rip140 were remarkably up-regulated. Transwell assay showed that the over-expression of RIP140 inhibited N2a cell migration ((70 ± 20) vs (5 ± 4) cells, P < 0.05). CCK-8 assay showed that the proliferation rates of N2a group at 24, 48, 72 h were 1.567 ± 0.107, 3.018 ± 0.212 and 4.112 ± 0.221 respectively. And those of N2a-rip140 group were 1.561 ± 0.281, 2.232 ± 0.235 and 4.025 ± 0.217 respectively. No significant difference existed in proliferation rates at different timepoints among N2a, N2a-M and N2a-rip140 groups (all P > 0.05). RIP140 over-expression effectively inhibits N2a cell migration. However it has no significant effect on the proliferation of N2a cells.

Effects of receptor interacting protein 140 on the biological activity of glia cells

To explore the effects of receptor interacting protein (RIP) 140 gene overexpression upon the in vitro proliferation, apoptosis, invasion and migration of microglioma cells. The BV-2 RIP140 overexpression model (BV-2-1) was constructed by Lipofection and G418 selection, then validated by real-time PCR and Western blotting. The proliferation, apoptosis, invasion and migration potencies were compared between BV-2-1 and its parents by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium (MTT) assay, flow cytometry and Transwell chamber. The BV-2-1 model was successfully constructed. Compared to those of the BV-2 group, the RIP140 mRNA and protein expression levels of BV-2-1 were markedly higher than those of the BV-2 group (t = 49.794, P < 0.01). MTT assay showed that the absorbance values in the BV-2 group were 1.157 ± 0.013, 1.679 ± 0.005 and 2.609 ± 0.008 at 24, 48, and 72 hours respectively. And those were 0.929 ± 0.013, 1.188 ± 0.008 and 1.528 ± 0.012 in the BV-2-1 group respectively. The proliferation at the time points of 48 and 72 hours of the BV-2-1 group were significantly lower than that of the BV-2 group (t = 6.058 and 9.245, both P < 0.01). Annexin-V staining showed that there were significant differences in the apoptosis rates between the BV-2 and BV-2-1 cells [(5.35 ± 0.23)% vs (3.46 ± 0.45)%, t = 6.619, P = 0.003)]. Transwell assay showed that the invaded cell number of the BV-2-1 group was 166 ± 43. And it was obviously higher than that of the BV-2 group (93 ± 32, t = 3.403, P = 0.007). Transwell assay also showed that the migrated cell number of BV-2 cells was 101 ± 25. And the migration potency of the BV-2-1 group (202 ± 50) was significantly stronger than that of the BV-2 group (t = 4.104, P = 0.002). RIP140 effectively inhibits the proliferation and facilitates the apoptosis of microglioma cells. And it may effectively facilitate the in vitro invasion and migration of microglioma cells.