Failure pattern and suggestions for target volume delineation of carcinoma showing thymus-like differentiation treated with intensity-modulated radiotherapy.

BACKGROUND: To review our long-term clinical experience, analyze the failure patterns, and give suggestions for target volume delineation of carcinoma showing thymus-like differentiation (CASTLE) treated with intensity-modulated radiotherapy (IMRT). METHODS: From April 2008 to May 2019, 30 patients with CASTLE treated by postoperative or radical IMRT in our center were retrospectively reviewed. A total dose of 56-60 Gy in 28-30 fractions was prescribed to patients without residual disease and 66 Gy in 33 fractions for patients with residual or unresectable disease. Survival rates were calculated using the Kaplan-Meier method. Treatment-related toxicities were graded by National Cancer Institute Common Toxicity Criteria (NCI-CTC) version 4.0. RESULTS: Among the 30 patients, 12 (40%) received partial resection or biopsy. Lateral lymph node metastasis was observed in 7 (23.3%) patients. During follow-up, regional lymph node recurrence occurred in 2 patients and distant metastasis in 5 patients. With a median follow-up time of 63.5 months, the 5-year local recurrence-free survival (LRFS), regional recurrence-free survival (RRFS), distant metastasis-free survival (DMFS), overall survival (OS) and progression-free survival (PFS) rates were 100, 88.9, 78.9, 93.1 and 78.9%, respectively. For patients with no lateral neck node metastasis, prophylactic radiotherapy for lateral neck nodal regions failed to improve RRFS (p = 0.381) and OS (p = 0.153). CONCLUSION: Distant metastasis was the major failure pattern for CASTLE after surgery and IMRT. For patients with no lateral neck node metastasis, the omission of irradiation for lateral neck nodal regions seems to be safe and feasible.

Chloramine-T-Enabled Mass Spectrometric Analysis of C═C Isomers of Unsaturated Fatty Acids and Phosphatidylcholines in Human Thyroids.

Specific locations of carbon-carbon double bonds (C═C) in lipids often play an essential role in biological processes, and there has been a booming development in C═C composition analysis by mass spectrometry. However, a universal derivatization and fragmentation pattern for the annotation of C═C positions in lipids is still challenging and attractive. To expand this field in lipidomics, a flexible and convenient N-tosylaziridination method was developed, with high derivatization efficiency, sensitivity, and specificity. The derivatization was very fast (15 s), and C═C numbers as well as locations could be pinpointed specifically in tandem mass spectra. By qualitative and quantitative studies of paratumor and tumor thyroid tissues of human beings, the total content of unsaturated fatty acids was suggested to be increased in tumor tissues, and good correlations in and between lysophosphatidylcholines and phosphatidylcholines were revealed by Spearman analysis. Further studies of C═C isomers showed that n-6/n-3 ratios were closely associated with human thyroid tumorigenesis, and high ratios of n-6/n-3 isomers seemed to suffer a high risk of carcinogenesis. Other isomers were not very representative; however, C═C in n-9/n-7 could also be significant for oncology research. Generally, it is supposed that both total amounts and C═C isomer ratios were related to cancer, and N-tosylaziridine derivatization could provide an alternative strategy for the C═C isomer study of disease models.

Derivatization Strategy for Simultaneous Molecular Imaging of Phospholipids and Low-Abundance Free Fatty Acids in Thyroid Cancer Tissue Sections.

Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) has been applied in many fields for detecting and imaging a variety of metabolites. In cancer research, this fast-growing imaging method also helps to elucidate the connection between the changes of metabolites in the microenvironment and the proliferation and survival of cancer cells. Free fatty acids (FFAs) are a vital building block of phospholipids (PLs) that can serve as a second cellular messenger and provide nutrients in the cancer microenvironment. The metabolism process of FFAs and PLs is highly relevant to the initiation and progression of different cancers. To better understand the metabolism process in cancer tissues, simultaneously detecting and imaging FFAs and PLs is essential. Despite the crucial developments that have been performed in the field of lipids imaging, FFAs and PLs have rarely been detected and imaged simultaneously in positive ion mode with good detection sensitivity. In this work, an on-tissue derivatization method was used to add a permanently quaternary amine onto FFAs; then, the FFAs and PLs were simultaneously imaged in positive ion mode. The derivatized FFAs are suitable for detection in positive ion mode. In comparison with the traditional matrix and the previous derivatization method, our derivatization reagent has a higher sensitivity for imaging FFAs. In addition, for simultaneous imaging analysis of FFAs and PLs, the number of imaged FFAs and PLs is greater than that with the previous on-tissue derivatization method. This high-sensitivity on-tissue derivatization method was applied to detect and image PLs and fatty acids in thyroid cancer tissues. In the MSI experiment, FFA derivatives and PLs were imaged while molecular localization and tissue integrity were maintained. Meanwhile, the correlation between PLs and FFAs was also studied, and the results showed that the correlations between saturated FFAs of C16:0 and C18:0 and PLs are better than the correlations of unsaturated FFAs with PLs.

High-throughput screening and quantitation of guanidino and ureido compounds using liquid chromatography-drift tube ion mobility spectrometry-mass spectrometry.

The present work focused on the high-throughput screening and quantitation of guanidino compounds (GCs) and ureido compounds (UCs) in human thyroid tissues. The strategy employed benzylic rearrangement stable isotope labeling (BRSIL) for the sample preparation and then detection using liquid chromatography-drift tube ion mobility spectrometry-quadrupole time of flight mass spectrometry (LC-DTIMS-QTOF MS). A short reversed-phase LC realized an on-line desalting and a measurement cycle of 5.0 min. DTIMS separation enhanced the better specificity and selectivity for the benzil labeled GCs and UCs. The elevated mass resolution of QTOF MS enabled measure of the characteristic ions at accurate mass in MS and tandem MS spectra. Collision cross section (CCS) from DTIMS and accurate mass from QTOF MS were used as two qualifiers for the profiling and identification of GCs and UCs. In addition, an integral abundance arising from 3-D ion features (retention time, drift time, m/z) was applied to quantify the GCs and UCs in human thyroid tissues. The quantitative validation indicated good linearity (coefficient values ≥ 0.9981), good precision (1.0%-12.3% for intra-day and 0.9%-7.8% for inter-day) and good accuracy (91%-109%). The results demonstrated that the developed BRSIL coupled with LC-DTIMS-QTOF MS can be a powerful analysis platform to investigate GCs and UCs in human thyroid tissues.

Benzylic rearrangement stable isotope labeling for quantitation of guanidino and ureido compounds in thyroid tissues by liquid chromatography-electrospray ionization mass spectrometry.

Benzylic rearrangement stable isotope labeling (BRSIL) was explored to quantify the guanidino and ureido compounds (GCs and UCs). This method employed a common reagent, benzil, to label the guanidino and ureido groups through nucleophilic attacking then benzylic migrating. The use of BRSIL was investigated in the analysis of five GCs (creatine, l-arginine, homoarginine, 4-guanidinobutyric acid, and methylguanidine) and two UCs (urea and citrulline). The labeling was found simple and specific. The introduction of bi-phenyl group and the generation of nitrogen heterocyclic ring in the benzil-d0/d5 labeled GCs and UCs improved the retention behaviors in liquid chromatography (LC) and increased the sensitivity of electrospray ionization mass spectrometry (ESI MS) detection. The fragment ion pairs of m/z 182/187 and m/z 210/215 from the benzil-d0/d5 tags facilitated the discovery of potential GCs and UCs candidates residing in biological matrices. The use of BRSIL combined with LC-ESI MS was applied for simultaneously quantitation of GCs and UCs in thyroid tissues. It was demonstrated that nine GCs and UCs were detected, six of which were further quantified based on corresponding standards. It was concluded that five GCs and UCs (l-arginine, homoarginine, 4-guanidinobutyric acid, methylguanidine, and citrulline) were statistically significantly different (p < 0.05) between the para-carcinoma and carcinoma thyroid tissue samples.

miR-584 Suppresses Invasion and Cell Migration of Thyroid Carcinoma by Regulating the Target Oncogene ROCK1.

BACKGROUND: Uncovering the target gene of miR-584 to control thyroid carcinoma (TC) invasion and migration is of central importance in the diagnosis, treatment, and prognosis of TC. To validate whether miR-584 has a tumor-suppressive role in thyroid cancer cells by targeting ROCK1, a series of experiments were conducted to figure out the mechanism of action of miR-584. MATERIAL AND METHODS: Migration analyses and cell proliferation assays were performed using miR-584-transfected cells. The expression levels of miR-584 in TC were detected by using real-time polymerase chain reaction (PCR). Western blot analyses were conducted to find out the relationship between the tumor suppressor miR-584 and the target oncogene ROCK1 protein expression levels. Wound healing experiments were used to examine the relationships between miR-584 and the migration of thyroid cancer K1 cells and the effects of ROCK1 knockdown on K1 cell motility. RESULTS: Our results demonstrate that altering the miR-584 levels affects human thyroid cancer cell migration, but has no effect on cell proliferation. The relative ROCK-1 expression levels were 1 and 0.54 in the scrambled-sequence control group and the miR-584 group, respectively. K1 cells transfected with siRNA-ROCK-1 showed weaker cell migration than cells transfected with siRNA-NC (negative control); the cell motility ratios were 18% and 27%, respectively. CONCLUSION: These results indicate that miR-584 could inhibit the expression of ROCK1, and ROCK1 knockdown would further affect the migration ability of K1 cells.

Characteristics and prognosis of primary thyroid non-Hodgkin's lymphoma in Chinese patients.

BACKGROUND AND OBJECTIVES: There exists no universally accepted treatment for primary thyroid non-Hodgkin's lymphoma (TNHL) due to the rarity of this entity. The aim of this study is to assess the role of surgery and to explore prognostic factors in Chinese TNHL patients. METHODS: Patient presentations, pathologies, surgical interventions, multidisciplinary treatment, prognostic factors and the value of fine needle aspiration were analyzed. RESULTS: Between 1991 and 2007, 40 patients of TNHL were diagnosed. Thirty-eight patients underwent an initial surgical procedure. Further treatments consisted of radiotherapy or chemotherapy alone, and the majority of patients were treated with combined chemo-radiation. After a median follow-up of 95 months, the 5-year overall survival (OS) and relapse-free survival (RFS) was 82% and 74%, respectively. Survival curves showed no significant difference between therapeutic operations when compared with diagnostic operations. A univariate analysis showed both International Prognostic Index (IPI) and staging significantly influenced OS and RFS. In multivariate analysis, IPI was found to be the only prognostic factor. CONCLUSIONS: Combined chemotherapy and radiotherapy may offer better outcome without the need for extensive resection, and surgery should be reserved to providing tissue for diagnosis. The patients with low-intermediate risk (IPI = 2) or stage IIE need be treated more aggressively.

[Clinical and pathological analysis of central compartment dissection in patients with papillary thyroid cancer with negative clinical lymph node metastasis].

OBJECTIVE: To assess the significance of central compartment dissection in papillary thyroid cancer with negative clinical lymph node metastasis. METHODS: Clinical and pathological data of 641 papillary thyroid cancer patients with negative clinical lymph node metastasis who were treated from January 1998 to April 2006 were collected. The positive rate of the lymph nodes metastasis was analyzed. The relations between the central compartment lymph nodes and the patients' gender, age, tumor size and number were concerned. Among the 641 cases, 114 case who received operation more than five years were followed up for the relations between the pathological status of central compartment lymph nodes and ipsilateral neck metastasis or contra thyroid lobe recurrence. RESULTS: The median number of the central compartment lymph nodes was 4 each case and 53.0% (340/641) cases of papillary thyroid cancer patients with negative clinical lymph node metastasis had positive central compartment lymph nodes metastasis. Large tumor size and multiple origins were related to central compartment lymph nodes involvement, but the patients' gender or age was not. In the 114 follow-up cases, ipsilateral neck metastasis occurred in 12 cases, among which 11 cases had high positive central compartment lymph nodes metastasis. Contra thyroid lobe recurrence occurred in 5 cases, whose statuses of central compartment lymph nodes were different. CONCLUSIONS: Papillary thyroid cancer patients with negative clinical lymph node metastasis deserve formal central compartment dissection. The pathological status of central compartment lymph nodes relates to the tumor size and number. High positive rate of central compartment lymph nodes may lead to possible ipsilateral neck metastasis.

[Somatic mutations of mitochondrial DNA in thyroid papillary carcinoma].

OBJECTIVE: To analyze the somatic mutations in the D-loop of mtDNA and further evaluate the possibility of mitochondrial genetic instability in thyroid papillary carcinoma. METHODS: Hypervariable regions ( HVR-I and HVR-II) in the D-loop of mtDNA from the specimen of 35 thyroid papillary cancers and matched lymphocytes were amplified by PCR, and then were sequenced. RESULTS: Comparing the sequences of tumors to those of matched lymphocytes and normal thyroid tissues, 5 somatic mutations in 2 patients (5.7%) were found. Two mutations were insertions of C in a poly-cytidine (nt303) microsatellite, and 3 at positions 73, 152 and 194 in HVR-II. In addition, of the 294 genetic variants detected, 292 were previously recorded polymorphisms, whereas 2 were new polymorphisms (nt324:C-->G, nt16092:T-->A). CONCLUSIONS: Mutations in the D-loop of mtDNA were found in thyroid papillary cancers, this mutation rate was lower than the reported rate of alteration in tumors of epithelial origin, and further work is required to elucidate the relationship between this mutations and the development of thyroid papillary carcinoma.