MicroRNAs in thyroid cancer with focus on medullary thyroid carcinoma:potential therapeutic targets and diagnostic/prognostic markers and web based tools

This review aimed to describe the inculpation of microRNAs(miRNAs)in thyroid cancer(TC)and its subtypes,mainly medullary thyroid carcinoma(MTC),and to outline web-based tools and databases for bioinformatics analysis of miRNAs in TC.Additionally,the capacity of miRNAs to serve as therapeutic targets and biomarkers in TC management will be discussed.This review is based on a literature search of relevant articles on the role of miRNAs in TC and its subtypes,mainly MTC.Additionally,web-based tools and databases for bioinformatics analysis of miRNAs in TC were identified and described.MiRNAs can perform as oncomiRs or antioncoges,relying on the target mRNAs they regulate.MiRNA replacement therapy using miRNA mimics or antimiRs that aim to suppress the function of certain miRNAs can be applied to correct miRNAs aberrantly expressed in diseases,particularly in cancer.MiRNAs are involved in the modulation of fundamental pathways related to cancer,resembling cell cycle checkpoints and DNA repair pathways.MiRNAs are also rather stable and can reliably be detected in different types of biological materials,rendering them favorable diagnosis and prognosis biomarkers as well.MiRNAs have emerged as promising tools for evaluating medical outcomes in TC and as possible therapeutic targets.The contribution of miRNAs in thyroid cancer,particularly MTC,is an active area of research,and the utility of web applications and databases for the biological data analysis of miRNAs in TC is becoming increasingly important.

Comparison between the Medullary Indexes of Hairs from Apodemus orestes and A.draco,with Discussion about the Taxonomic Status of A.orestes

The taxonomic status of long-tailed field mouse (Apodemus orestes) is still uncertain up to now.Some scholars regarded it as a subspecies or a synonym of dragon field mouse (A.draco),while other scholars considered it a valid species.In the study,five specimens of adult long-tailed field mouse,dragon field mouse and Chevrier's field mouse (A.chevrieri) (as a contrast) were chosen respectively.After treated,with the eyepiece micrometer in the inverted microscope,we made measurements of the widths of hairs and medullas and then calculated the medullary indexes of straight guard hairs from around the mouth,head,back,abdomen and forelimb of each species.The results indicate that,viewing at each of the five parts and the mixture of the five parts,there are no significant differences between A.orestes and A.draco,Significant differences can be found between A.orestes & A.chevrieri and A.draco & A.chevrieri though.The standpoint that A.orestes was listed as a valid species is not supported by this study.

THE MORPHOLOGICAL MEASURE OF THE TIBIAL MEDULLARY CAVITY AND ITS SIGNIFICANCE

Objective To provide morphological reference for the designing of the intramedullary nail fixation which suitable for Chinese by investigating the morphological characteristics of tibial medullary cavity. Methods The morphological parameters of the 113 normal adult tibiale were measured on the X-ray photographs with the image analysis software. Results The total lengths of tibial medullary cavities were 299.49±11.03 mm(male) and 274.60± 6.77 mm(female), and the lengths of the narrow part were 66.36±3.90 mm(male) and 51.57±3.92mm(female). The end-points of narrow part were about 29.9 mm(male) and 26.09 mm(female)below the midpoints of medullary cavities. The radians of the longitudinal axes of medullary cavities were 2.53±1.27°(male) and 2.57±1.16°(female). The proximal opening K were 9.47±2.71(male) and 8.59±2.46(female). The distal opening K were 8.21± 2.93(male)and 7.65±2.87(female). Conclusion The morphology of tibial medullary cavity, the characteristic variety of radian and the opening K were very important references for designing the Chinese intramedullary nail fixation.

Neurotoxicity of prenatal alcohol exposure on medullary pre-B?tzinger complex neurons in neonatal rats

Prenatal alcohol exposure disrupts the development of normal fetal respiratory function, but whether it perturbs respiratory rhythmical discharge activity is unclear. Furthermore, it is unknown whether the 5-hydroxytryptamine 2A receptor（5-HT2AR） is involved in the effects of prenatal alcohol exposure. In the present study, pregnant female rats received drinking water containing alcohol at concentrations of 0%, 1%, 2%, 4%, 8% or 10%（v/v） throughout the gestation period. Slices of the medulla from 2-day-old neonatal rats were obtained to record respiratory rhythmical discharge activity. 5-HT2 AR protein and m RNA levels in the pre-B？tzinger complex of the respiratory center were measured by western blot analysis and quantitative RT-PCR, respectively. Compared with the 0% alcohol group, respiratory rhythmical discharge activity in medullary slices in the 4%, 8% and 10% alcohol groups was decreased, and the reduction was greatest in the 8% alcohol group. Respiratory rhythmical discharge activity in the 10% alcohol group was irregular. Thus, 8% was the most effective alcohol concentration at attenuating respiratory rhythmical discharge activity. These findings suggest that prenatal alcohol exposure attenuates respiratory rhythmical discharge activity in neonatal rats by downregulating 5-HT2 AR protein and m RNA levels.

Investigation of Calcitonin and Calcitonin Gene-related Peptide in 88 Cases of Medullary Thyroid Carcinoma

Objective： To investigate the changes of calcitonin （CT） and calcitonin gene-related peptide （CGRP） in patients with medullary thyroid carcinoma （MTC）. Methods： Fifty-eight cases of MTC were selected and the relationship between the CT levels and metastasis was investigated. The immunohistochemical method was used to detect the expression of CT and CGRP in the 58 samples of MTC tissues. The CT and CGRP in 30 newly diagnosed MTC inpatients were measured before operation and in the first few days after operation using a radioimmunoassy. Results： （1） The rate of residual tumor had a significant difference between the normal serum CT group one month after operation and the elevated group at the same period （P〈0.01）. （2） Immunohistochemical study revealed the positive rate of CT was about 98%, and that of the CGRP was 87.8%. （3） Part of the patients had an elevated CGRP levels while CT levels was normal. （4） The serum CT levels were decreased to a stable range one week after operation. Conclusion： CT is a useful index to evaluate the efficacy of surgical treatment. The measurement of serum CGRP is helpful in the diagnosis of MTC, especially for those whose preoperative CT levels are normal.

Acute coronary syndrome: a rare case of multiple endocrine neoplasia syndromes with pheochromocytoma and medullary thyroid carcinoma

Pheochromocytoma is a tumor arising from neuroectodermal chromaffin tissues in the adrenal gland or extra-adrenal paraganglia(paragangliomas). The prevalence of the tumor is 0.1%-0.6% in the hypertensive population, of which 10%-20% are malignant. Pheochromocytoma produces, stores, and secretes catecholamines, as well as leads to hypertensive crisis, arrhythmia, angina, and acute myocardial infarction without coronary artery diseases. We report a case of acute coronary syndrome(ACS) with a final diagnosis of multiple endocrine neoplasia with pheochromocytoma and medullary thyroid carcinoma(MTC).

Is new American Thyroid Association risk classification for hereditary medullary thyroid carcinoma applicable to Chinese patients? A single-center study

Objective: The American Thyroid Association (ATA) proposed a new risk classification for hereditary medullary thyroid carcinoma (MTC) in 2015. This study aimed to assess whether the new guidelines are suitable for the Chinese population, and reported our experience on prophylactic thyroidectomy. Methods: A total of 73 patients from 22 families were screened as rearranged during transfection (RET) mutation carriers from 2010 to 2016 in Cancer Hospital, Chinese Academy of Medical Science; the medical history for each patient was collected. Based on the initial treatment, we identified the risk factors for poor prognosis by univariate and multivariate logistic regression. Then, 4 RET mutation carriers were enrolled for prophylactic thyroidectomy, and their pathological data and follow-up outcomes were recorded. Results: In univariate and multivariate logistic regression analyses, age at initial surgery and risk classification were significant risk factors for stage III/IV hereditary MTC at initial diagnosis. The likelihood was increased by 11.6% per year of age at initial surgery [95% confidence interval (95% CI), 1.040-1.198; P=0.002). It was 7.888 times more likely to have III/IV stage disease for ATA highest risk patients, compared to ATA moderate risk individuals (95% CI, 1.607-38.717; P=0.003). Postoperative pathological results showed all 4 multiple endocrine neoplasia type 2A (MEN2A) patients had C-cell hyperplasia (CCH); multifocal malignancies were detected in 3 of them. All 4 patients were cured biochemically, and none developed permanent hypoparathyroidism. Conclusions: In Chinese individuals, hereditary MTC aggressiveness is in line with the new ATA risk classification. Germline RET gene mutation carriers should undergo prophylactic thyroidectomy according to basal serum calcitonin levels.

Clinical and functional comparison of endoprosthetic replacement with intramedullary nailing for treating proximal femur metastasis

Objective： To evaluate the clinical and functional outcomes of modular endoprosthetic replacement （EPR） compared to proximal femur intramedullary nailing （IMN） for the treatment of proximal femur metastases. Methods： We retrospectively studied the records of patients with proximal femur metastatic lesions treated with surgical stabilization between January 2007 and December 2014 in terms of operation time, blood loss, postoperative score, soreness, Karnofsky performance score （KPS） and survival time. Results： There were 34 patients treated with surgical stabilization. The mean follow-up period was 12.1~8.6 months （range： 10-47 months）. Thirteen were treated with EPR and 21 were stabilized with IMN （20 males, 14 females; mean age： 68.7 years）. The median survival time was 11.0 months for both groups （P=0.147）. The operation time, blood loss and Harris score of IMN group were lower than those of EPR group （P=0.001, P=0.001, P=0.002, respectively）. Conclusions： Both EPR and IMN for treating proximal femur metastasis achieved effective clinical outcomes. Therefore, the suitable surgical methods depended on the general conditions and medical requirements of patients, as well as the technical advantages of the doctor.

Recurrent medullary thyroid carcinoma treated with percutaneous ultrasound-guided radiofrequency ablation:A case report

BACKGROUND Treatment for neck lymph node metastases after adequate initial surgery in medullary thyroid carcinoma(MTC)has been controversial.Ultrasound(US)-guided radiofrequency ablation(RFA)has been widely used in recurrent welldifferentiated thyroid carcinoma.Here,we report for the first time the use of RFA in a patient with recurrent MTC.CASE SUMMARY We report the case of a 56-year-old woman with cervical lymph node metastases of MTC.Four years previously,she had undergone a total thyroidectomy and neck lymph node dissection.A neck US revealed many enlarged nodes during the follow-up period.Moreover,the serum calcitonin jumped to 198.17 pg/mL,which strongly indicated the recurrence of MTC.Subsequently,two metastatic lymph nodes were confirmed by US-guided fine-needle aspiration-cytology and fineneedle aspiration-calcitonin,and then the patient was treated with RFA.Four months later,the neck US and a contrast-enhanced US showed obvious shrinkage in the ablation zones,and the serum calcitonin dropped to 11.80 pg/mL.CONCLUSION This case suggests that RFA may be an effective and safe treatment for local recurrent MTC.

Do medullary thyroid carcinoma patients with high calcitonin require bilateral neck lymph node clearance?A case report

BACKGROUND In clinical work,85%-90%of malignant thyroid diseases are papillary thyroid cancer(PTC);thus,clinicians neglect other types of thyroid cancer,such as medullary thyroid carcinoma(MTC).CASE SUMMARY We report a 53-year-old female patient with a preoperative calcitonin level of 345 pg/mL.There was no definitive diagnosis of MTC by preoperative fine-needle aspiration cytology or intraoperative frozen pathology,but the presence of PTC and MTC was confirmed by postoperative paraffin pathology.The patient underwent total thyroidectomy and bilateral central lymph node dissection.Close follow-up at 1.5 years after surgery revealed no signs of recurrence or metastasis.CONCLUSION The issue in clinical work-up regarding types of thyroid cancer provides a novel and challenging idea for the surgical treatment of MTC.In the absence of central lymph node metastasis,it is worth addressing whether patients with high calcitonin can undergo total thyroidectomy and bilateral central lymph node dissection without bilateral lateral neck lymph node dissection.

Effect of parathyroid hormone on apoptosis of human medullary thyroid carcinoma cells

Objective The aim of the study was to investigate the effect of parathyroid hormone(PTH) on the apoptosis of human medullary thyroid carcinoma(MTC) cells.Methods In vitro cultured medullary thyroid carcinoma cell lines were treated with parathyroid hormone and parathyroid hormone receptor-monoclonal antibody,and the apoptosis of cells was detected by flow cytometry.Results The cell morphology changed significantly after treatment based on the observation using the inverted phase-contrast microscope.Various concentrations of parathyroid hormone and parathyroid hormone receptor-monoclonal antibody effectively induced apoptosis in a time-and concentrationdependent manner.When the concentration of parathyroid hormone was 2.0 μmol/L and that of parathyroid hormone receptor-monoclonal antibody was 1.0 μmol/L,the apoptotic rate was 13.24% and 20.78%,respectively,representing a statistically significant difference from that of the control cells(P < 0.05).Conclusion PTH plays a role in inducing apoptosis of human MTC cells.

Inhibition effects of parathyroid hormone on human medullary thyroid carcinoma cells

Objective： The purpose of the study was to investigate the effects of parathyroid hormone and parathyroid hormone receptor monoclonal antibody on in vitro growth and proliferation of human medullary thyroid carcinoma cell lines. Methods： The medullary thyroid carcinoma cell line was cultured in vitro, with parathyroid hormone and parathyroid hormone receptor monoclonal antibody treatment intervention, the growth of the cells was observed under an inverted contrast micro scope, the MTT assay was used to detect the cell growth inhibition rate. Results： Under the inverted contrast microscope, the cells changed significantly, the parathyroid hormone and parathyroid hormone receptor monoclonal antibodies can effectively inhibit the proliferation of medullary thyroid cancer cells in a time and dose dependent. When parathyroid hormone concentra tion reached a concentration of 2.0 IJmol/L, the parathyroid hormone receptor monoclonal antibody reached a concentration of 1.0 μmol/L, the cell growth was most significantly inhibited （P 〈 0.05）. Conclusion： Parathyroid hormone and parathyroid hormone receptor monoclonal antibody were able to inhibit the proliferation of medullary thyroid carcinoma cells and signifi cantly reduce the proliferation index.

Effects of rearranged during transfection mutation on calcitonin and procalcitonin expression in sporadic medullary thyroid carcinoma

Objective The aim of this study was to investigate the effects of rearranged during transfection(RET)mutation on the expressions of calcitonin(CTn)and procalcitonin(PCT)in sporadic medullary thyroid carcinoma(SMTC).Methods RET mutation was detected by polymerase chain reaction direct sequencing in 64 cases of SMTC,and the expression levels of CTn and PCT in SMTC tissues were detected using the immunohistochemical streptavidin-perosidase(SP)method.The effect of RET mutations on the expression of CTn and PCT along with its relationship with clinicopathological parameters were analyzed.Results The expression rates of CTn and PCT in SMTC tissues were 90.6%(58/64)and 67.2%(43/64),respectively.CTn and PCT expression were found to be associated with tumor size and lymph node metastasis(P<0.05)but not with gender,age,or tumor capsule invasion(P>0.05).There was a significant correlation between CTn and PCT expression(r=0.269,P=0.041),and the intensity of positive CTn expression was positively correlated with RET mutation(r=0.507,P=0.000).However,PCT expression was not associated with RET mutation(r=0.188,P=0.136).Conclusion High expression of CTn and PCT was associated with the progression of medullary carcinoma,and the intensity of CTn expression was associated with RET mutation.PCT may provide valuable information for the diagnosis and prognosis of SMTC.

Gingival enlargement induced by cyclosporine in Medullary aplasia:A case report

BACKGROUND Cyclosporine is an immunosuppressive agent used effectively for treatment of a rare haematological disorder known as medullary aplasia.This drug prevents several side effects,including gingival enlargement(GE)which compromises aesthetics,phonetics and chewing,and also predisposes patients to periodontitis.CASE SUMMARY This clinical case reports a 41-year-old woman who presented with cyclosporineinduced GE with underlying periodontitis and medullary aplasia.The management of the disease was approached through multidisciplinary strategy which allowed for accurate diagnosis and a strategic treatment based on the systemic condition and severity of oral pathology.The diagnosis was confirmed through histopathological analysis.The treatment was carried out in phases:Initial(oral hygiene motivation,mechanical supragingival plaque control,and non-surgical therapy);systemic treatment,corrective treatment,and maintenance.CONCLUSION Multidisciplinary management of cyclosporine-induced GE and medullary aplasia allows for correct diagnosis and effective treatment of this pathological expression through a phased therapeutic approach.

Connections between 5-HT-containing terminals and 5-HT_(2A) recep tor and γ-aminobutyric acid or glycine co-existed neurons in the rat medullary dorsal horn

Objective: To investigatetheconnectionsbetweenserotonin(5-HT)-containingterminalsand5-HT 2A receptor(5-HT 2A R)/γ-aminobutyricacid(GABA)or5-HT 2A R/glycineco-existedneuronsin theratmedullarydorsalhorn(MDH).Meth ods:Immunofluorescencehistochemicaltriple-stainingfor5-HT,5-HT 2A R,GABAor glycine.Results:5-HT-im-munoreactivefibersandterminalswerechieflylocatedinthesuperficiallaminae(laminaeⅠandⅡ)of theMDH.Neurons exhibiting5-HT 2A R-,GABA-or glycine-immunoreactivitiesweremainlyobservedin the superficiallaminae.Some5-HT 2A R-immunopositiveneuronsalsoexhibitedGABA-or glycine-immunoreactivities.5-HT-containingterminalsmade closecontactswith5-HT 2A R/GABAor5-HT 2A R/glycineco-existedneurons.Conclusion:5-HT 2A R/GABAor5-HT 2A R/glycineco-existinsomeof theneuronsinthesuperficiallaminaeof theMDH.5-HT-immunoreactiveterminalsformclose connectionswith5-HT 2A R/GABAor5-HT 2A R/glycineco-existedneurons.

Effects of Hyperosmolality on Expression of Urea Transporter A2 and Aquaporin 2 in Mouse Medullary Collecting Duct Cells

In this study,the effects of hyperosmolality on the expression of urea transporter A2 (UTA2) and aquaporin 2 (AQP2) were investigated in transfected immortalized mouse medullary collecting duct (mIMCD3) cell line.AQP2-GFP-pCMV6 and UTA2-GFP-pCMV6 plasmids were stably transfected into mIMCD3 cells respectively.Transfected mIMCD3 and control cells were cultured in different hy-pertonic media,which were made by NaCl alone,urea alone,or an equiosmolar mixture of NaCl and urea.The mRNA and protein expression of AQP2 was elevated by the stimulation of NaCl alone,urea alone and NaCl plus urea in AQP2-mIMCD3 cells;whereas NaCl alone and NaCl plus urea rather than urea alone increased the mRNA and protein expression of UTA2 in UTA2-mIMCD3 cells,and all the expression presented an osmolality-dependent manner.Moreover,the mRNA and protein expression of UTA2 rather than AQP2 was found to be synergistically up-regulated by a combination of NaCl and urea in mIMCD3 cells.It is concluded that NaCl and urea synergistically induce the expression of UTA2 rather than AQP2 in mIMCD3 cells,and hyperosmolality probably mediates the expression of AQP2 and UTA2 through different mechanisms.

Incidental diagnosis of medullary thyroid carcinoma due to persistently elevated procalcitonin in a patient with COVID-19 pneumonia:A case report

BACKGROUND Procalcitonin(Pct)is a common biomarker in clinical practice,especially in the era of coronavirus disease 2019(COVID-19)infection.Although it is frequently used for the diagnosis and prognostication of bacterial infections or sepsis,it is also elevated in a few other conditions,including medullary thyroid carcinoma(MTC).CASE SUMMARY A 43-year-old female presented with moderately severe COVID-19 pneumonia in April 2021.She gradually recovered clinically;however,despite normalization of other inflammatory markers,Pct levels remained persistently elevated.Further workup identified the cause as left lobe MTC with locoregional metastasis.Calcitonin levels were high,and carcinoembryonic antigen levels were normal.The patient underwent total thyroidectomy and neck dissection,which was followed by another radical neck dissection due to residual disease.Currently,she is doing well,nearly having completed her course of external beam radiotherapy with no recurrence.Pct is well documented as a screening tool for MTC,especially because of its stable nature compared to calcitonin in the community settings.It is important to keep in mind the differential diagnosis of MTC in patients with persistently elevated Pct levels despite normal levels of other acute phase reactants.To the best of our knowledge,this is the first report from Asia of such an incidental diagnosis of MTC due to persistently elevated Pct levels in a patient with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection.CONCLUSION Persistently elevated Pct levels can occur in any pro-inflammatory state including infections,sepsis,or acute respiratory distress syndrome.In the current setting,SARS-CoV-2 infection is one such clinical scenario,and in rare situations of persistent elevation,MTC may need to be ruled out.

Distribution of several neural active substances in medullary visceralzone in cat

objective: The distribution of catecholamine (tyrosine hydroxylase as marker), serotonin and neuropeptides (substance P, neuropeptide Y and Met-enkephaline) immunoreactive positive structures (nerve cell bodies, nerve fibers and terminals ) were investigated in medullary visceral zone (MVZ) of the cat. Meth ods: Immunohistochemical ABC method was used. Results: The above-mentioned immunoreactive positive structures are relatively densely distributed in the MVZ of the cat, which is an arc zone from the dorsomedial region to the ventrolateral region in the coronal section of the middle and caudal medulla oblongata. Conclu sion: lt is suggested that the MVZ of the cat is a relatively independent functional structural area.

Fos expression in the medullary visceral zone following transient decrease of blood pressure in rats under simulated weightlessness

Objective: To observe Fos expression after transient decrease of blood pressure in catecholaminergic neurons of the medullary visceral zone(MVZ) in simulated weightlessness rats. Methods: Simulated weightlessness was abtained by tail suspension for 4 weeks, and transient decrease of blood pressure was induced by intravenous injection of sodium nitroprusside. Fos expression in catechlaminergic neurons of MVZ were visualized by an immunohistochemical double-labeling technique with anti-Fos and anti-tyrosine hydroxylase (TH) antibodies. Results: The decrease of blood pressure in the simulated weightlessness rats resulted in Fos expression in many neurons of the medulla oblongata, and they were primarily localized in the MVZ. In the MVZ, Fos-positive neurons were concentrated in the nucleus of the solitary tract (NTS) and ventrolateral region of the medulla (VLM). On the other hand, the numbers of Fos-positive neurons in MVZ were smaller than that of control rats (treated with tail suspension or intravenous injection of sodium nitroprusside only). Although some TH-positive neurons were found to be Fos-positive, the proportion of TH/Fos double-labeled neurons was much lower than that of the control rats; intensity of TH-like immunoreactivity was also reduced. Conclusion: The decrease of Fos-positive neurons and proportion of catechlaminergic neurons expressing Fos protein may result from decrease of parasympathetic activity in the simulated weightlessness rats.

Ambiguous clear cell carcinoma in medullary sponge kidney:A case report

Medullary sponge kidney(MSK)is a characteristic renal malformation,with a relatively low incidence.Radiologically,identification of MSK is sometimes ambiguous when compared to a renal mass.Here,we report a novel renal clear cell carcinoma in MSK,and discuss our approach to treatment.We recommended that a preoperative biopsy should be performed,followed by a comprehensive discussion regarding the appropriate perioperative preparations and careful surgical techniques that should be performed for this complex disease.