Hyeon-Gun Jee

Comprehensive Analysis of the Transcriptional and Mutational Landscape of Follicular and Papillary Thyroid Cancers.

Follicular thyroid carcinoma (FTC) and benign follicular adenoma (FA) are indistinguishable by preoperative diagnosis due to their similar histological features. Here we report the first RNA sequencing study of these tumors, with data for 30 minimally invasive FTCs (miFTCs) and 25 FAs. We also compared 77 classical papillary thyroid carcinomas (cPTCs) and 48 follicular variant of PTCs (FVPTCs) to observe the differences in their molecular properties. Mutations in H/K/NRAS, DICER1, EIF1AX, IDH1, PTEN, SOS1, and SPOP were identified in miFTC or FA. We identified a low frequency of fusion genes in miFTC (only one, PAX8–PPARG), but a high frequency of that in PTC (17.60%). The frequencies of BRAFV600E and H/K/NRAS mutations were substantially different in miFTC and cPTC, and those of FVPTC were intermediate between miFTC and cPTC. Gene expression analysis demonstrated three molecular subtypes regardless of their histological features, including Non–BRAF–Non–RAS (NBNR), as well as BRAF–like and RAS–like. The novel molecular subtype, NBNR, was associated with DICER1, EIF1AX, IDH1, PTEN, SOS1, SPOP, and PAX8–PPARG. The transcriptome of miFTC or encapsulated FVPTC was indistinguishable from that of FA, providing a molecular explanation for the similarly indolent behavior of these tumors. We identified upregulation of genes that are related to mitochondrial biogenesis including ESRRA and PPARGC1A in oncocytic follicular thyroid neoplasm. Arm-level copy number variations were correlated to histological and molecular characteristics. These results expanded the current molecular understanding of thyroid cancer and may lead to new diagnostic and therapeutic approaches to the disease.

Berberine Inhibited the Growth of Thyroid Cancer Cell Lines 8505C and TPC1

Purpose Thyroid cancer is the most common malignancy in Korean females and can be treated with good prognosis. However, drugs to treat aggressive types of thyroid cancer such as poorly differentiated or anaplastic thyroid cancer have not yet been established. To that end, we analyzed the effects of berberine on human thyroid cancer cell lines to determine whether this compound is useful in the treatment of aggressive thyroid cancer. Materials and Methods The two thyroid cancer cell lines 8505C and TPC1, under adherent culture conditions, were treated with berberine and analyzed for changes in cell growth, cell cycle duration, and degree of apoptosis. Results Following berberine treatment, both cell lines showed a dose-dependent reduction in growth rate. 8505C cells showed significantly increased levels of apoptosis following berberine treatment, whereas TPC1 cells showed cell cycle arrest at the G0/G1 phase. Immunobloting of p-27 expression following berberine treatment showed that berberine induced a little up-regulation of p-27 in 8505c cells but relatively high up-regulation of p-27 in TPC1 cells. Conclusion These results suggest that berberine treatment of thyroid cancer can inhibit proliferation through apoptosis and/or cell cycle arrest. Thus, berberine may be a novel anticancer drug for the treatment of poorly differentiated or anaplastic thyroid cancer.

Sulforaphane Inhibits Oral Carcinoma Cell Migration and Invasion In Vitro

Sulforaphane is a predominant isothiocyanate in Brassica oleracea, a family of cruciferous vegetables, and is known to be inversely related to the risk of various types of human carcinomas. Studies using oral carcinoma cell lines are scarce, however, and the role of sulforaphane on oral carcinoma cell metastasis is yet to be determined. In this study, the growth inhibition of oral carcinoma cell lines by sulforaphane was determined using aqueous soluble tetrazolium salts, and the growth of various oral cancer cell lines was attenuated. The migration and invasion activities of the cells also decreased, as observed in monolayer scratch assays and transwell invasion experiments. The molecular change behind the impairment of the migration and invasion was investigated via secreted metalloprotease level detection using Multiplex protein analysis kits. At the molecular level, the secreted forms of MMP‐1 and MMP‐2 were down‐regulated. The expressions of MMP‐1 and MMP‐2 did not change when a conventional tumoricidal agent paclitaxel was used. These findings indicate that sulforaphane may have therapeutic potential as an inhibitor of metastasis in oral carcinoma patients. Copyright

CD24 cross-linking induces apoptosis in, and inhibits migration of, MCF-7 breast cancer cells

BackgroundThe biological effects of CD24 (FL-80) cross-linking on breast cancer cells have not yet been established. We examined the impact of CD24 cross-linking on human breast cancer cell line MCF-7.MethodsMCF-7 and MDA-MB-231 cells were treated with anti-rabbit polyclonal IgG or anti-human CD24 rabbit polyclonal antibodies to induce cross-linking, and then growth was studied. Changes in cell characteristics such as cell cycle modulation, cell death, survival in three-dimensional cultures, adhesion, and migration ability were assayed after CD24 cross-linking in MCF-7.ResultsExpression of CD24 was analyzed by flow cytometry in MDA-MB-231 and MCF-7 cells where 2% and 66% expression frequencies were observed, respectively. CD24 cross-linking resulted in time-dependent proliferation reduction in MCF-7 cells, but no reduction in MDA-MB-231 cells. MCF-7 cell survival was reduced by 15% in three-dimensional culture after CD24 cross-linking. Increased MCF-7 cell apoptosis was observed after CD24 cross-linking, but no cell cycle arrest was observed in that condition. The migration capacity of MCF-7 cells was diminished by 30% after CD24 cross-linking.ConclusionOur results showed that CD24 cross-linking induced apoptosis and inhibited migration in MCF-7 breast cancer cells. We conclude that CD24 may be considered as a novel therapeutic target for breast cancer.

Development of a canine model for recurrent laryngeal injury by harmonic scalpel

Various energy devices had been used in thyroid surgery. Aim of study is to develop canine model for recurrent laryngeal nerve injury by harmonic scalpel and to evaluate feasibility of using this model for evaluating the safety use of harmonic scalpel during thyroid surgery. Nine dogs were divided into 3 groups according to distance between harmonic scalpel application and recurrent laryngeal nerve; group 1 (1 mm), 2 (2 mm), and 3 (3 mm). Vocal cord function was assessed pre- and postoperatively using video laryngoscopy. Harmonic scalpel was applied adjacent to left recurrent laryngeal nerve and, two weeks later, right recurrent laryngeal nerve at assigned distances. Recurrent laryngeal nerves were evaluated for subacute and acute morphologic changes. Laryngoscopy demonstrated 3 abnormal vocal cords in group 1, 1 in group 2, and no in group 3 (P=0.020). Subacute histologic changes were observed in nerves with abnormal function. Acute histologic changes were observed 5/8 (62.5%) in group 1, 1/7 (14.3%) in group 2, and not in group 3. We developed canine model for recurrent laryngeal injury. The functional outcomes matched with the histologic changes. These warrant further study to determine the safety margin for energy device in vicinity of recurrent laryngeal nerve.

Combined effect of Hashimoto's thyroiditis and BRAFV600E mutation status on aggressiveness in papillary thyroid cancer

The purpose of this study was to evaluate the association between Hashimotos thyroiditis and BRAFV600E mutation status in patients with papillary thyroid cancer (PTC) and to determine their combined association with tumor aggressiveness in PTC.

Is There a Treatment Advantage When Paclitaxel and Lovastatin Are Combined to Dose Anaplastic Thyroid Carcinoma Cell Lines

BACKGROUND Anaplastic thyroid carcinoma (ATC) is the most aggressive type of thyroid carcinoma. The purpose of this study was to evaluate the combined cytotoxic effects of paclitaxel and lovastatin in ATC cell lines. METHODS ATC cells were treated with paclitaxel and lovastatin, separately or together, and the cytotoxicity of the compounds was determined by quantifying cell viability and apoptosis. We conducted an isobologram analysis to investigate the combined effect of the two drugs. RESULTS In 8505C cells, cellular viability was inhibited by lovastatin and paclitaxel in a concentration-dependent manner (p = 0.002 and p = 0.020, respectively). The IC(50) of lovastatin was 3.53 μM and that of paclitaxel was 5.98 nM. In BHT-101 cells, cellular viability was also inhibited in a concentration-dependent manner by lovastatin and paclitaxel (p = 0.020 and p = 0.032, respectively). The IC(50) of lovastatin was 17.13 μM and that of paclitaxel was 35.26 nM. In 8505C cells, paclitaxel and lovastatin alone induced apoptosis in a concentration-dependent manner. However, both an isobologram analysis on inhibition of viability and an analysis of apoptosis demonstrated antagonism between paclitaxel and lovastatin. In BHT-101 cells, however, neither drug had an apoptotic effect when used individually. There was a variable effect when used in combination, depending on the drug concentrations. CONCLUSIONS Paclitaxel and lovastatin were cytotoxic in two ATC cell lines and increased apoptosis in 8505C cells. However, in these cells, the combination of drugs resulted in antagonism that affected both the cytotoxicity of the compounds and the apoptosis of 8505C cells. The combination of paclitaxel and lovastatin did not enhance the treatment effect in ATC cell lines.

Natural Head Postures of Patients With Facial Asymmetry in Frontal View Are Corrected After Orthognathic Surgeries

PURPOSE Although orthognathic surgeries focus on adjustment of facial asymmetry (FA), many clinicians know by experience that the natural head posture (NHP) also is corrected after the surgery. The authors examined whether this was indeed the case by the measuring the NHP during the course of orthognathic treatment. Factors associated with NHP correction also were evaluated. PATIENTS AND METHODS In this retrospective study, clinical features, including the NHP, of patients with FA and those with facial symmetry (FS) were compared. They were outpatients of a private orthodontic dental clinic from December 2008 to March 2012. The degree of NHP tilt was evaluated using an interpupillary (IP) horizontal angle. The NHP of patients with FA were analyzed further before presurgical orthodontic treatment, after presurgical orthodontic treatment, after orthognathic surgery and postsurgical orthodontic treatment, and 1 year after completion of postsurgical orthodontic treatment. The NHP difference at each time point was analyzed using 1-way analysis of variance. An analysis of factors that influence NHP tilt correction was performed by linear regression. RESULTS Thirty-one patients with FA and 27 with FS were evaluated. The NHP tilt was more profound in the FA group compared with the FS group. There were more patients with skeletal Class III in the FA group. The degree of NHP tilt in the FA group was decreased after orthognathic surgery and postsurgical orthodontic treatment and remained when measured 1 year later. Women were less prone than men to NHP tilt correction by orthognathic surgery. CONCLUSION Patients with FA have a tilted NHP compared with those with FS. Orthognathic surgery for FA might correct a tilted NHP to a lesser degree in women.

Side population in LX2 cells decreased by transforming growth factor-β

Side population (SP) cells are known to be enriched in stem/progenitor‐like cells. Transforming growth factor (TGF)‐β signaling is associated with extracellular matrix (ECM) production in hepatic stellate cells. We hypothesized that the SP fraction in LX2 cells is associated with ECM deposition, which is regulated through TGF‐β signaling.

JNK signaling in hepatocarcinoma cells is associated with the side population upon treatment with anticancer drugs

Liver cancer is one of the most drug-resistant cancer types, and cancer stem cells are related to drug resistance. c-Jun-N-terminal kinase (JNK) signaling is involved in drug resistance, and the side population of cells (SP cells) can be used as a model to study liver cancer stem cells. We sought to evaluate the relationship between SP cells and JNK signaling in hepatocarcinoma cells. For this purpose, we examined cell proliferation and the SP cell ratio following treatment of Huh7 cells with the anticancer drugs 5-fluorouracil (5-FU) and paclitaxel. The expression of phospho-stress-activated protein kinase (SAPK)/JNK in the treated cells was evaluated using immunoblotting. 5-FU and paclitaxel treatment increased the number of SP cells and JNK phosphorylation, and decreased cell survival. Huh7 and HepG2 cells were also treated with SP600125, a JNK inhibitor, to study the relationship between SP cells and JNK signaling. The increase in the number of SP cells and the SAPK/JNK and c-Jun phosphorylation was reverted by SP600125 treatment in these cells. We also used immunohistochemistry and showed that SAPK/JNK and c-Jun phosphorylation are increased in hepatocarcinoma tissues. In conclusion, our results demonstrate that the number of SP cells and SAPK/JNK phosphorylation are increased upon treatment with anticancer drugs, and that this increase is blocked by inhibition of JNK signaling. These findings suggest that drug resistance in liver cancer may involve an increase in the number of SP cells following JNK activation.