KISS-1 knockdown inhibits cell growth, migration, and invasion in HTR-8/SVneo cells by regulating the GRP54-mediated PI3K/AKT signaling pathway

Recurrent spontaneous abortions (RSA) affect reproductive health and increase the risk of subsequent abortions. To investigate the role of KISS-1/GPR-54 signaling in RSA progression. Villus tissue was collected from RSA patients, and human trophoblastic HTR-8/SVneo cells were used. KISS-1 and GRP54 levels were detected using RT-qPCR and immunohistochemistry. Western blotting was performed to analyze ZO-1 and ZEB1 levels. Cell proliferation was determined via CCK-8 and cell clone formation assays. Transwell assays were performed to assess cell migration and invasion abilities. KISS-1 was down-regulated in the villus tissues of RSA patients. KISS-1 overexpression dramatically inhibited trophoblast proliferation, migration, and invasion. Mechanistically, ZEB1 expression was down-regulated, whereas ZO-1 expression was up-regulated, after KISS-1 overexpression. GPR54 silencing neutralized the effect of KISS-1 in HTR-8/SVneo cells. Additionally, KISS-1 overexpression inactivated the PI3K/AKT signaling pathway through GRP54. The KISS-1/GPR-54 signaling axis regulates RSA progression by regulating the PI3K/AKT signaling pathway.

KISS-1, Mediated by Promoter Methylation, Suppresses Esophageal Squamous Cell Carcinoma Metastasis via MMP2/9/MAPK Axis

BACKGROUND AND AIMS

KISS-1 is an established tumor suppressor that inhibits metastases in various malignancies. However, little is known regarding its role in esophageal squamous cell carcinoma (ESCC). The aim of the present study was to identify the possible mechanisms of KISS-1 in ESCC metastasis.

METHODS

The expression levels of KISS-1 mRNA and protein in ESCC samples and cell lines were analyzed by qRT-PCR, IHC, and western blotting. Bisulfite sequencing PCR (BSP) and methylation-specific PCR (MSP) were used to analyze the methylation pattern of KISS-1 promoter in ESCC cells with or without 5-Aza-dC treatment. The role of KISS-1 in the progression and metastasis of ESCC was analyzed through in vitro functional assays.

RESULTS

KISS-1 mRNA and protein were markedly downregulated in ESCC tissues and cell lines compared to the respective controls. Hypermethylation of KISS-1 promoter correlated to its lower expression levels in ESCC, and KISS-1 demethylation inhibited tumor progression. Ectopic KISS-1 overexpression inhibited tumor cell metastasis in vitro. In addition, KISS-1 overexpression downregulated the matrix metalloproteinase 2 and 9 (MMP2 and 9) and inhibited epithelial-mesenchymal transition (EMT). Finally, KISS-1 downregulated phosphorylated extracellular regulated protein kinase 1/2 (ERK1/2) and phosphorylated p38 mitogen-activated protein kinase (MAPK) without affecting their total expression levels in the ESCC cells. MAPK/ERK and p38 MAPK agonists reversed the suppressive effects of KISS-1.

CONCLUSIONS

The hypermethylation of KISS-1 promoter partly contributed to its downregulation in ESCC. KISS-1 inhibits the metastasis of ESCC cells by targeting the MMP2/9/ERK/p38 MAPK axis.

[Expressions of MACC1, Snail, and KISS-1 Proteins in Infiltrating Breast Carcinoma and Its Clinicopathological Features]

OBJECTIVES

To investigate the protein expressions of metastasis-associated in colon cancer 1 (MACC1), KISS-1 (a cancer ruppressor gene) and Snail (the marker of epithelial-mesenchymal transition) in infiltrating breast carcinoma (IBC) and explore the role of them in invasion, metastasis and prognosis in IBC.

METHODS

Expressions of MACC1, Snail and KISS-1 were examined by immunohistochemistry in 250 specimens of IBC and 80 specimens of normal breast tissues. Their clinicopathological features were analyzed, and their influence on patients' survival was identified.

RESULTS

The positive rate of MACC1, Snail and KISS-1 in normal breast tissues and IBC tissues was 7.5%, 5.0%, 87.5% and 63.6%, 58.8%, 38.0%, respectively. And there was a significant difference between the IBC group and control group ( P<0.05). The positive expressions of MACC1, Snail and KISS-1 were significantly different in different TNM stages, lymph node metastasis, types and grades of tumor ( P<0.05). The survival time of positive KISS-1 group was significantly longer than that of negative group ( P<0.001); the survival time was significantly shorter in positive MACC1 group or Snail group than that of negative groups (both P<0.001). Cox regression analysis indicated that the positive expressions of MACC1, Snail and negative expression of KISS-1 were independent risk factors of IBC (P<0.05).

CONCLUSIONS

Abnormal expression of MACC1, Snail and KISS-1 should be involved in the invasion and metastasis of IBC. The combined detection in the expressions of MACC1, Snail and KISS-1 at the early stage may play an important role in predicting the progression and prognosis of IBC.

KISS-1 inhibits the proliferation and invasion of gastric carcinoma cells

AIM: To investigate the function of the KISS-1 gene in gastric carcinoma cells and to explore its potential mechanism.

METHODS: A KISS-1 eukaryotic expression vector was constructed and transfected into BGC-823 cells. Resistant clones were obtained through G418 selection. reverse transcription-polymerase chain reaction and western blotting were used to detect KISS-1 and matrix metalloproteinase-9 (MMP-9) expression in transfected cells. The growth of transfected cells was investigated by 3-(4, 5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) proliferation assays, and the cells’ invasive potential was analyzed by basement membrane (Matrigel) invasion assays. The anti-tumor effects of KISS-1 were tested in vivo using allografts in nude mice.

RESULTS: The expression level of KISS-1 mRNA and protein in BGC-823/KISS-1 transfected cells were significantly higher than in BGC-823/pcDNA3.1 transfected cells (P < 0.05) or the parental BGC-823 cell line (P < 0.05). The expression level of MMP-9 mRNA and protein in BGC-823/KISS-1 were significantly less than in BGC-823/pcDNA3.1 (P < 0.05) or BGC-823 cells (P < 0.05). MTT growth assays show the proliferation of BGC-823/KISS-1 cells at 48 h (0.642 ± 0.130) and 72 h (0.530 ± 0.164) were significantly reduced compared to BGC-823/pcDNA3.1 (0.750 ± 0.163, 0.645 ± 0.140) (P < 0.05) and BGC-823 cells (0.782 ± 0.137, 0.685 ± 0.111) (P < 0.05). Invasion assays indicate the invasive potential of BGC-823/KISS-1 cells (16.50 ± 14.88) is significantly reduced compared to BGC-823/pcDNA3.1 (20.22 ± 14.87) (P < 0.05) and BGC-823 cells after 24 h (22.12 ± 16.12) (P < 0.05). In vivo studies demonstrate the rate of pcDNA3.1-KISS-1 tumor growth is significantly slower than pcDNA3.1 and control cell tumor growth in nude mice. Furthermore, tumor volume of pcDNA3.1-KISS-1 tumors (939.38 ± 82.08 mm³) was significantly less than pcDNA3.1 (1250.46 ± 44.36 mm³) and control tumors (1284.36 ± 55.26 mm³) (P < 0.05). Moreover, the tumor mass of pcDNA3.1-KISS-1 tumors (0.494 ± 0.84 g) was significantly less than pcDNA3.1 (0.668 ± 0.55 g) and control tumors (0.682 ± 0.38 g) (P < 0.05).

CONCLUSION: KISS-1 may inhibit the proliferation and invasion of gastric carcinoma cells in vitro and in vivo through the downregulation of MMP-9.