ABSTRACT
BACKGROUND AND AIM: To compare blood and salivary levels of lipofuscin in healthy adults and to analyze the relationship between the lipofuscin level and the healthy adults' age. METHODS: One hundred and twenty-two healthy volunteers were recruited and divided into three groups according to their age: young (n = 42, 20-44 years old), middle-aged (n = 51, 45-59 years old), and elderly (n = 29, 60-74 years old). One ml saliva and 5 ml whole blood were collected from each person. An ELISA kit was used to measure both the plasma and salivary lipofuscin levels. The differences between the groups were compared with independent-sample t test, and the relationship between the salivary lipofuscin level and the age was assessed with linear regression analysis. RESULTS: The mean ± SD of the lipofuscin level in the saliva and plasma of 122 subjects was 68.93 ± 1.32 and 78.05 ± 1.75 µmol/l, respectively. No gender-dependent differences were observed in either the salivary or the plasma lipofuscin level (saliva: p = 0.443, plasma: p = 0.459). The salivary and plasma lipofuscin levels of the elderly subjects were significantly higher than those of the young (saliva: 80.72 ± 13.53 mmol/l versus 59.12 ± 1.92 mmol/l, p = 0.0003; plasma: 93.31 ± 3.14 mmol/l versus 67.43 ± 2.54 mmol/l, p = 0.0002) and middle-aged (saliva: 80.72 ± 13.53 mmol/l versus 70.31 ± 11.17 mmol/l, p = 0.0004; plasma: 93.31 ± 3.14 mmol/l versus 78.12 ± 2.40 mmol/l, p = 0.0002) subjects. Similarly, the salivary and plasma lipofuscin levels of the middle-aged subjects were significantly higher than those of the young subjects (saliva: 70.31 ± 11.17 mmol/l versus 59.12 ± 1.92 mmol/l, p < 0.0001; plasma: 78.12 ± 2.40 mmol/l versus 67.43 ± 2.54 mmol/l, p = 0.0019). The lipofuscin levels in the saliva and plasma were significantly positively correlated with the subject age (r = 0.551, p = 0.0001; r = 0.528, p < 0.0001). Furthermore, the salivary lipofuscin level and plasma lipofuscin level also were found to have a positive correlation (r = 0.621, p < 0.0001). CONCLUSION: No gender-dependent differences were observed in either the salivary or plasma lipofuscin levels. The salivary and plasma lipofuscin levels were positively correlated, and the age is positively correlated with lipofuscin content in saliva.
Subject(s)
Aging/metabolism , Lipofuscin , Saliva/metabolism , Adult , Aged , Female , Healthy Volunteers , Humans , Linear Models , Lipofuscin/blood , Lipofuscin/metabolism , Male , Middle Aged , Sex Factors , Statistics as TopicABSTRACT
The Fork head box C1 (FOXC1) gene is overexpressed in multiple malignant tumors and is functionally correlated with tumor progression. However, its' role in oral squamous cell carcinoma (OSCC) is still unclear. Recent studies have revealed that many long non-coding RNA (lncRNAs) cooperate with adjacent coding genes and form a functional "lncRNA-mRNA pair". In this study, we report a new lncRNA FOXC1 upstream transcript (FOXCUT) that was remarkably overexpressed in 23 OSCC patients, as was the adjacent FOXC1 gene. The expressions of FOXC1 and FOXCUT were positively correlated. When the expression of FOXCUT was down-regulated by small interfering RNA (siRNA), the expression of FOXC1 was also decreased. Moreover, in OSCC cells Tca8113 and SCC-9, down-regulation of either FOXC1 or FOXCUT by siRNA could inhibit cell proliferation and cell migration in vitro and was accompanied with a reduction of MMP2, MMP7, MMP9, and VEGF-A. In conclusion, FOXC1 may be co-amplified with FOXCUT in OSCC, and both of them may be functionally involved in the tumor progression of OSCC. This provides evidence that both FOXC1 and FOXCUT may serve as novel biomarkers and therapeutic targets in OSCC patients who overexpress this "lncRNA-mRNA pair".
