Downregulation of SLC5A8 inhibits hepatocellular carcinoma progression through regulation of Wnt/β-catenin signaling

Role of hypermethylated SLC5A8 in follicular thyroid cancer diagnosis and prognosis prediction

OBJECTIVE

Thyroid cancer is one of the most frequently reported endocrine system malignancies. It is difficult to distinguish follicular thyroid cancer (FTC) from follicular thyroid adenoma (FTA) during pathological diagnosis in patients without lymph nodes or distant metastases. Therefore, we conducted a retrospective study to investigate the significance of SLC5A8 methylation and expression in the diagnosis and prognosis of FTC.

METHODS

We used 165 tissue samples, including FTC (n = 58), thyroid tumors of uncertain malignant potential (TT-UMP, n = 40), and FTA (n = 67), to explore the differences in SLC5A8 methylation and mRNA transcription in different pathological types. Survival analysis was conducted to evaluate the recurrence rate at a 5-year follow-up.

RESULTS

The SLC5A8 methylation positive rate was higher in patients with thyroglobulin ≥ 40 μg/l and Chol ≥ 5.17 mmol/l, and it was higher in patients with FTC (n = 42, 72.4%) than those with FTA (n = 27, 40.3%) and TT-UMP (n = 23, 57.5%). The relative concentration of SLC5A8 mRNA was lower in patients with FTC than in those with FTA (p < 0.05). At 5-year follow-ups, patients who were SLC5A8 methylation-positive had a higher recurrence rate than those who were methylation-negative.

CONCLUSIONS

Our current study indicates that SLC5A8 gene methylation occurs more commonly in patients with FTC than in those with FTA. The differences in SLC5A8 methylation and expression among FTA, FTC, and TT-UMP provide an important basis for further exploration of epigenetic changes in the occurrence, development, and prognosis of thyroid cancer. Our findings need to be further validated in larger populations with long-term follow-up in the future.

Lactobacillus plantarum-derived metabolites sensitize the tumor-suppressive effects of butyrate by regulating the functional expression of SMCT1 in 5-FU-resistant colorectal cancer cells

A critical obstacle to the successful treatment of colorectal cancer (CRC) is chemoresistance. Chemoresistant CRC cells contribute to treatment failure by providing a mechanism of drug lethargy and modifying chemoresistance-associated molecules. The gut microbiota provide prophylactic and therapeutic effects by targeting CRC through anticancer mechanisms. Among them, Lactobacillus plantarum contributes to the health of the host and is clinically effective in treating CRC. This study confirmed that 5-fluorouracil (5-FU)-resistant CRC HCT116 (HCT116/5FUR) cells acquired butyrate-insensitive properties. To date, the relationship between 5-FU-resistant CRC and butyrate resistance has not been elucidated. Here, we demonstrated that the acquisition of butyrate resistance in HCT116/5FUR cells was strongly correlated with the inhibition of the expression and function of SMCT1, a major transporter of butyrate in colonocytes. L. plantarum-cultured cell-free supernatant (LP) restored the functional expression of SMCT1 in HCT116/5FUR cells, leading to butyrate-induced antiproliferative effect and apoptosis. These results suggest that LP has a synergistic effect on the SMCT1/butyrate-mediated tumor suppressor function and is a potential chemosensitizer to overcome dual 5-FU and butyrate resistance in HCT116 cells.

Holliday junction-recognizing protein promotes cell proliferation and correlates with unfavorable clinical outcome of hepatocellular carcinoma

AIM

To investigate the expression and clinical significance of Holliday junction-recognizing protein (HJURP) in hepatocellular carcinoma (HCC).

METHODS

In this study, we detected the expression of HJURP protein in samples of 164 patients with HCC, and based on this, we divided the patients into two cohorts: high expression of HJURP and low expression of HJURP. We analyzed the correlation between HJURP expression and the clinicopathological factors using chi-square test. Survival significance of HJURP was defined by Kaplan-Meier method and log-rank test, and the independent prognostic factors were identified by Cox regression model. Using function assays of HCC cell lines, we investigated the influence of HJURP on the proliferation of HCC cells.

RESULTS

In our study, the proportion of patients with high HJURP expression was 25.6%, which was significantly associated with the tumor size and Barcelona clinic liver cancer stage. Univariate analysis confirmed that high HJURP expression was remarkably associated with poorer overall survival rates (P=0.003), as well as tumor number (P=0.016), tumor differentiation (P=0.047), TNM stage (P=0.005), and Barcelona clinic liver cancer stage (P=0.004). Multivariate analysis confirmed that high HJURP expression (P<0.001) acted as an independent prognostic risk factor of unfavorable prognosis. Real-time polymerase chain reaction analysis revealed that the expression of HJURP was significantly higher in HCC tissues than that in the corresponding normal liver tissues. Moreover, we demonstrated that HJURP overexpression could accelerate HCC cell line proliferation, whereas HJURP knockdown could attenuate the proliferation.

CONCLUSION

High HJURP expression was an independent prognostic biomarker of HCC, predicting poorer prognosis. HJURP also played an important role in HCC cell proliferation.