A simple procedure for routine RNA extraction and miRNA array analyses from a single thyroidin vivofine needle aspirate

Added value of circulating miRNA expression profiling to sonographic TI-RADS classification in the diagnosis of thyroid nodules

Potential use of sonographic TI-RADS classification combined with circulating miRNA expression profiling in the diagnosis of thyroid nodules was explored. Retrospective analysis was performed on clinical data of 121 patients with thyroid nodules. The biopsy specimens of patients obtained through ultrasound-guided aspiration and blood specimens were evaluated in Zhengzhou Central Hospital Affiliated to Zhengzhou University from June 2018 to June 2019. In addition, the blood specimen test results of 121 healthy volunteers (control group) who underwent physical examination were retrospectively analyzed. Results of sonographic TI-RADS classification and circulating miRNA expression profiling were compared with the pathological results. Of the 212 nodules, 2 fell into TI-RADS category 2 and were diagnosed as benign. Malignant nodules accounted for 4.35, 37.14, 84.78, 93.33 and 96.77% of those nodules that fell into TI-RADS categories 3, 4a, 4b, 4c and 5, respectively. Of the 121 patients, 92.55% had with nodular goiter, 3.31% had inflammatory nodules, 2.48% toxic nodular goiter, 0.83% thyroid cysts and 0.83% thyroid tumors. A nodule that fell into a higher TI-RADS classification category had a higher risk of malignancy. The expression levels of miRNA146b, miRNA187, miRNA375, miRNA-222-3p and miRNA-151a-5p were higher, while the level of miRNA138 was lower, in patients with either benign or malignant thyroid nodules compaed to those in the control group. The expression levels of miRNA146b, miRNA187, miRNA375, miRNA-222-3p and miRNA-151a-5p were higher, while the level of miRNA138 was lower, in patients with malignant thyroid nodules than those in patients with benign thyroid nodule (P<0.05). The AUC of the combined diagnostic method was 0.973, which was significantly different from the AUCs of the individual diagnostic method (P<0.05). In conclusion, sonographic TI-RADS classification combined with circulating miRNA expression profiling can improve the diagnosis of thyroid nodules.

[Clinical importance of thyroid gland cytology]

The cytological evaluation of fine needle biopsies (FNB) of the thyroid gland crucially depends on a close cooperation between clinicians and cytopathologists. Scintigraphy, sonography as well as clinical data and patient history are necessary for a correct interpretation of the indications for FNB; moreover, these data are of outstanding importance for cytopathologists for the correct interpretation of the cytomorphological findings. This overview describes the present standards in the acquisition, technical workup and cytopathological interpretation of thyroid gland tissue obtained by FNB, particularly focusing on the rapidly growing relevance of additional molecular pathological investigations to increase the diagnostic accuracy of thyroid FNB.

microRNA expression in autonomous thyroid adenomas: Correlation with mRNA regulation

The objective of the study was to identify the deregulated miRNA in autonomous adenoma and to correlate the data with mRNA regulation. Seven autonomous adenoma with adjacent healthy thyroid tissues were investigated. Twelve miRNAs were downregulated and one was upregulated in the tumors. Combining bioinformatic mRNA target prediction and microarray data on mRNA regulations allowed to identify mRNA targets of our deregulated miRNAs. A large enrichment in mRNA encoding proteins involved in extracellular matrix organization and different phosphodiesterases were identified among these putative targets. The direct interaction between miR-101-3p and miR-144-3p and PDE4D mRNA was experimentally validated. The global miRNA profiles were not greatly modified, confirming the definition of these tumors as minimal deviation tumors. These results support a role for miRNA in the regulation of extracellular matrix proteins and tissue remodeling occurring during tumor development, and in the important negative feedback of the cAMP pathway, which limits the consequences of its constitutive activation in these tumors.

Differentiating benign from malignant thyroid nodules using micro ribonucleic acid amplification in residual cells obtained by fine needle aspiration biopsy

BACKGROUND

Fine needle aspiration biopsy (FNAB) is the most commonly used diagnostic tool to differentiate benign from malignant thyroid nodules. Nevertheless, some FNAB cytology results are not definite. In such cases diagnostic thyroid lobectomy is performed with malignancy rate on final histopathology ranging at 15%-75%. The aim of this study was to improve on the accuracy of FNAB-based cytology by amplification of microRNAs (micro ribonucleic acids [miRs]) from the residual cells left in the FNAB needle after submission for cytology.

METHODS

Residual cells were collected from the needle cup after FNAB cytology of 77 consecutive patients with thyroid nodules. miR-enriched RNA was extracted for all patients with cytology showing either follicular lesion or suspicion for malignancy (n=11). The expression of miR-21, -31, -146b, -187, -221, and -222 was determined using real-time polymerase chain reaction. Results were compared with final surgical histopathology.

RESULTS

RNA was successfully extracted from all FNAB specimens. Five patients had FNAB cytology suspicious for malignancy. The miR panel was positive in all five (100%). Six patients had follicular lesions on FNAB. The miR panel was positive in three of four patients (75%) with confirmed malignancy and was negative in two of two (0%) patients with benign pathology results. This corresponded to a specificity of 100%, sensitivity of 88%, and accuracy of 90%.

CONCLUSIONS

RNA extraction from FNAB residual cells is feasible, and a miR panel amplified from the extracted RNA seems like a promising diagnostic tool in this limited number of patients.

Construction of Plasmid Insulin Gene Vector Containing Metallothionein IIA (pcDNAMTChIns) and Carbohydrate Response Element (ChoRE), and Its Expression in NIH3T3 Cell Line

BACKGROUND

Type 1 diabetes mellitus is one of the metabolic diseases that cause insulin-producing pancreatic ß cells be destroyed by immune system self-reactive T cells. Recent-ly, new treatment methods have been developed including use of the stem cells, ß islet cells transplantation and gene therapy by viral and non-viral gene constructs.

OBJECTIVES

The aim of this project was preparing the non-viral vector containing the glucose inducible insulin gene and using it in the NIH3T3 cell line.

MATERIALS AND METHODS

Cloning was carried out by standard methods. Total RNA was extracted from pancreatic tissue, RNA was converted to cDNA using RT-PCR reaction and preproinsulin gene was amplified using specific primers. PNMTCH plasmid was extract-ed and digested by NotI, HindIII, and MTIIA and ChoRE genes were purified and cloned into pcDNA3.1 (-) plasmid and named pcDNAMTCh. Finally, the preproinsulin genes were cloned into pcDNA3.1 (-) plasmid and pcDNAMTChIns was built.

RESULTS

The cloned gene constructs were evaluated by restriction enzyme digestion and RT-PCR. The NIH3T3 cells were transfected by plasmid naked DNA containing preproinsu-lin gene and expression was confirmed by Reverse Transcriptase PCR and Western Blot-ting Techniques.

CONCLUSIONS

Gel electrophoresis of PCR products confirmed that cloning was per-formed correctly. The expression of preproinsulin gene in recombinant plasmid in NI-H3T3 cell line was observed for the first time. The findings in this study can be the basis of further research on diabetes mellitus type 1 gene therapy on animals.