Expression of Circulating MicroRNA-141 in Epithelial Ovarian Cancer

BACKGROUND

Epithelial ovarian cancer (EOC) is a lethal disease due to late diagnosis and lack of effective screening methods. MicroRNA (miR/miRNA) plays an important role in ovarian carcinogenesis and may serve as a non-invasive biomarker for EOC. This study aimed to assess miR-141 expression in the blood plasma of patients with EOC and healthy subjects and determine its association with the clinical stage of EOC.

METHODS

This cross-sectional study used blood plasma from 30 newly diagnosed untreated patients with EOC and 25 healthy subjects. The mean age was 47.73 (SD = 10.29) years for EOC and 44.48 (SD = 16.14) years for healthy subject. The total RNA was isolated from blood plasma and reversed transcribed to obtain cDNA. The expression of miR-141 was measured by real-time quantitative polymerase chain reaction (qRT-PCR), and calculated using 2-ΔΔCt methods. The data were analysed using Mann-Whitney test.

RESULTS

The expression of miR-141 was upregulated 8.41 fold in the blood plasma of EOC patients compared to healthy controls (P < 0.001). Expression of miR-141 in the advanced stage was upregulated 4.2 fold compared to the early stage (P < 0.001).

CONCLUSION

The miR-141 was upregulated in the blood plasma of EOC and associated with an advanced stage of disease, suggesting it has potential as a biomarker for EOC detection.

Dynamic Changes of Circulating Mir-155 Expression and the Potential Application as a Non-Invasive Biomarker in Breast Cancer

Background:

Breast cancer incidence rates have been continuously increasing in majority nations with significant higher portion of cancer-related mortality in low- and middle-income countries. Developing new biomarker is an emerging field in the breast cancer research. Application of a promising minimally invasive biomarker, circulating microRNA, for additional improvement of diagnosis, prognosis, and therapeutic monitoring in breast cancer is not well corroborated.

Materials and Methods:

To uncover the potential use of circulating miR-155 expression as a clinical biomarker in breast cancer, we analyzed 102 breast cancer patients at diagnosis and after treatment as well as 15 healthy women. Total RNA was isolated from patient’s plasma and expression of circulating miR-155 was measured with quantitative reverse transcription polymerase chain reaction (qRT-PCR). The expression levels of circulating miR-155 were compared according to the effect of treatment, clinicopathological variables, and progression-free survival.

Results:

In comparison to the healthy women, expression of circulating miR-155 levels were significantly higher (medians were 18.49±19 and 1.28±0.18, respectively; p<0.0001). The expression levels of miR-155 were significantly diminished after patients completed surgery and chemotherapy (medians were 18.49±19 at diagnosis and 1.32±0.22 after treatment, respectively; p<0.0001). Patients older than 40 years old expressed higher circulating miR-155 than those younger than 40 years-old (medians were 28.92±22 and 4.19±2.49, respectively; p<0.0001). Circulating miR-155 was significantly higher in patients with tumors larger than 5 cm (44.27±2.6 vs 9.17±6.9, p=0.03). MiR-155 expression levels were not significantly different according to various tumor grades, subtypes, and clinical stages. Although longer follow-up is required, progression-free survivals of patients with upregulation of circulating miR-155 were significantly longer (mean survivals were 77 and 65 weeks, Log-rank (Mantel-Cox) test p=0.038).

Conclusion:

Expression of circulating miR-155 expression was significantly elevated in breast cancer patients and was decreased after treatment. Therefore, circulating miR-155 is potentially applicable as diagnostic therapeutic monitoring marker in breast cancer.

Upregulation of Circulating MiR-21 Expression as a Potential Biomarker for Therapeutic Monitoring and Clinical Outcome in Breast Cancer

Background: Aberrant patterns of microRNA expression have been highlighted as a potential clinical biomarker in breast cancer as the most frequent cancer among women that contributes nearly a quarter of total cancer incidence in 2018. Upregulation of microRNA-21 (miR-21) is associated with adverse clinical outcomes in breast cancer. However, the use of circulating free miR-21 as a non-invasive biomarker for diagnosis and therapeutic monitoring in breast cancer is not well established. We quantified the levels of circulating miR-21 expression and analyzed their correlation with clinicopathological variables and progression-free survival. Materials and Methods: This initial study included a cohort of 102 breast cancer patients of different subtypes and clinicat stages. We also included 15 unrelated healthy women. Venous blood from patients was collected at diagnosis and after treatment of surgery and chemotherapy. MiR-21 expression was quantified from total RNA fraction isolated from patient’s plasma. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to analyzed miR-21 expression. Results: Expression of circulating miR-21 was significantly elevated in breast cancer patients compared to healthy women (median miR-21 expression levels were 7.67±2.2 and 1.28±0.16, respectively; p<0.0001). Significant reduction of miR-21 expression was observed in breast cancer patients after completion of surgery and chemotherapy (median miR-21 expression levels were 7.67±2.2 at diagnosis and 2.16±1.28 after treatment, respectively; p<0.0001). MiR-21 expression was higher in breast cancer patients younger than 40-year-old but was not significantly different according to different histopathological grades and clinical stages at diagnosis. Patients with upregulation of circulating miR-21 were associated with poor progression-free survival (median survival 72 vs 86 weeks, respectively; log-rank (Mantel-Cox) test, p=0.049). Conclusion: MiR-21 expression was upregulated in breast cancer patients and might serve as a therapeutic monitoring marker.