International and subnational variation thyroid cancer incidence and mortality over 2008–2012

miR-144-3p Contributes to the Development of Thyroid Tumors Through the PTEN/PI3K/AKT Pathway

Purpose

To explore the expression and related mechanism of miR-144-3p and PTEN in thyroid cancer (TC).

Patients and Methods

From February 2018 to November 2019, 62 patients with TC who received treatment in Chengwu Hospital Affiliated to Shandong First Medical University were collected. TC cells and human normal thyroid HTori-3 cells were purchased. The miR-144-3p-inhibitor, miR-144-3p-mimics, empty vector plasmid (miRNA-NC), si-PTEN and sh-PTEN were transfected into B-CPAP and HTh-7 cells. The expressions of miR-144-3p and PTEN in the specimens were tested by qRT-PCR (qP). WB was used to detect the expression of Bcl-2, APR3, N-cadherin, Slug and Bax proteins in the cells. The cell proliferation was detected by MTT, and the cell invasion was tested by Transwell. The apoptosis was detected by flow cytometry (FC).

Results

miR-144-3p was highly expressed and PTEN was weakly expressed in the patients’ tissues. The AUC of miR-144-3p and PTEN was >0.8. miR-144-3p and PTEN were related to TNM stage, lymph node metastasis and differentiation degree of TC patients. The B-CPAP and HTh-7 with the greatest expression differences were selected for transfection. The expression of miR-144-3p in miR-144-3p-inhibitor group was significantly lower than that in NC group (P<0.01), and that in miR-144-3p-mimics group was significantly higher than that in NC group (p < 0.01). The expression of PTEN in si-PTEN group was significantly lower than that in NC group (P<0.01), while that in sh-PTEN group was significantly higher than that in NC group (P<0.01). Silencing miR-144-3p and overexpressing PTEN could inhibit cell proliferation, invasion and promote apoptosis. WB detection uncovered that silencing the miR-144-3p expression and overexpressing PTEN could inhibit the PI3K, Akt, p-AKT, Bcl-2, APR3 and cyclinD1 proteins and promote the up-regulation of Bax expression. Rescue experiments revealed that the cell proliferation, invasion and apoptosis were not different from NC after co-transfection of miR-144-3p-mimics+sh-PTEN and miR-144-3p-inhibitor+si-PTEN into B-CPAP and HTh-7.

Conclusion

Inhibition of miR-144-3p expression can up-regulate PTEN and affect cell proliferation, invasion and apoptosis, which may be a potential therapeutic target for TC.

Geographic influences in the global rise of thyroid cancer

The incidence of thyroid cancer is on the rise, and this disease is projected to become the fourth leading type of cancer across the globe. From 1990 to 2013, the global age-standardized incidence rate of thyroid cancer increased by 20%. This global rise in incidence has been attributed to several factors, including increased detection of early tumours, the elevated prevalence of modifiable individual risk factors (for example, obesity) and increased exposure to environmental risk factors (for example, iodine levels). In this Review, we explore proven and novel hypotheses for how modifiable risk factors and environmental exposures might be driving the worldwide increase in the incidence of thyroid cancer. Although overscreening and the increased diagnosis of possibly clinically insignificant disease might have a role in certain parts of the world, other areas could be experiencing a true increase in incidence due to elevated exposure risks. In the current era of personalized medicine, national and international registry data should be applied to identify populations who are at increased risk for the development of thyroid cancer.