Modifying impact of RET gene haplotypes on medullary thyroid carcinoma clinical course.

The clinical course of medullary thyroid carcinoma (MTC) associated with the MEN2A syndrome as well as of sporadic MTC shows considerable heterogeneity. The disease picture varies not only between the same RET proto-oncogene mutation carriers but also among sporadic MTC patients with no RET germinal mutations, which suggests the involvement of additional modulators of the disease. However, genetic factors responsible for this heterogeneity of the MTC clinical course still remain unknown. The aim of this study was to determine if polymorphic variants or specific haplotypes of the RET gene may modify the MTC clinical course. We genotyped the following loci: c.73+9277T>C, c.135G>A, c.1296A>G, c.2071G>A, c.2307T>C, c.2508C>T and c.2712C>G in 142 MTC patients and controls. We demonstrated considerable differences in the genotypes distribution within c.73+9277T>C, c.135G>A and c.2307T>C loci Our results show that the c.73+9277T variant associated with a decreased activity of the MCS+9.7 RET enhancer is rare in hereditary MTC patients with primary hyperparathyroidism, and thus, may influence the MTC clinical picture. The decreased activity of the RET promoter enhancer reduces RET expression level and may counterbalance the activating mutation in this gene. Frequent co-occurrence of the c.73+9277T allele with p.E768D, p.Y791F, p.V804M or p.R844Q RET mutations may be associated with their attenuation and milder clinical picture of the disease. Haplotypes analysis showed that C-G-A-G-T-(C)-C (c.73+9277T>C - c.135G>A - c.1296A>G - c.2071G>A - c.2307T>G - (c.2508C>T) - c.2712C>G) alleles combination predisposes to pheochromocytomas and primary hyperparathyroidism. We consider that RET haplotypes defining may become an auxiliary diagnostic tool in MTC patients.

Pituitary Microsomal Autoantibodies in Patients with Childhood-Onset Combined Pituitary Hormone Deficiency: an Antigen Identification Attempt.

The role of autoimmunization in the pathogenesis of pituitary disorders is poorly understood. The presence of pituitary autoantibodies (APA) has been detected in various pituitary disorders. Their role, however, remains elusive. Childhood-onset combined pituitary hormone deficiency (CPHD) may be caused by environmental or genetic factors. In some of patients, causes of the disease remain unclear and contributions of autoimmune processes have been postulated. The aim of this study was to identify the microsomes-derived pituitary antigens (MPA) as potential immunogenic autoantigens in patients with hypopituitarism, therefore 62 CPHD patients, 100 healthy controls and five autoimmune polyglandular syndrome type II (APS II) patients were included in the study. The clinical evaluation included hormonal tests and magnetic resonance imaging of the pituitary. The sources of MPA were pituitary glands taken from autopsies. Isolated MPA were then separated on SDS-PAGE gel and incubated with sera obtained from patients and controls. Microsomal APA were detected using Western blot and radioimmunological method. In all CPHD and APS II patients and in 9 % individuals from control group marked immunoreactivity was detected against MPA. Antibodies showed high affinity to 67, 60, 50 and 36 kDa MPAs. Since the identified autoantigens were of unknown nature, an in silico exploration of UniProt database was applied and indicated their possible relationship with chaperones, golgins and already known autoantigens like GAD67. Reactivity against MPA indicates that these proteins certainly play a role in the processes undergoing within pituitary of CPHD patients. The identification and further detailed studies on their role in the pathogenesis of CPHD should be continued.

Diagnosis, treatment, and prognosis in patients with liver metastases from follicular thyroid carcinoma (FTC).

Follicular thyroid carcinoma (FTC) is the second most common type of thyroid cancer (TC) and accounts for approximately 10% of all TC cases. Liver metastases are a rare presentation in 0.5-1% of follicular thyroid cancers, usually occurring in the setting of widely disseminated FTC disease, and their presence is associated with poor prognosis. Until now, there have been only 30 cases of FTC liver metastases described in the literature. Herein, we review publications and describe diagnostic tools that may be used in the diagnosis and follow-up of FTC metastases to the liver, including biopsy and imaging techniques like US, CT, MRI, SPECT, PET, and radioiodine scintigraphy. We also present and discuss current methods of treatment, e.g. TSH suppressive therapy with levothyroxine, surgery, radiofrequency ablation (RFA), transarterial embolisation (TAE), liver transarterial chemoembolisation (TACE), chemotherapy with cisplatin and doxorubicin, treatment with Indium- 111-octreotide (or its analogues), and tyrosine kinase inhibitors (sorafenib, sunitinib). At the end we describe the course, results of diagnostics, and treatment in a patient with large multiple FTC metastases to the liver. (Endokrynol Pol 2016; 67 (3): 332-347).

The c.470 T > C CHEK2 missense variant increases the risk of differentiated thyroid carcinoma in the Great Poland population.

BACKGROUND: Differentiated thyroid carcinoma (DTC) originates from thyroid follicular epithelial cells and belongs to a group of slowly progressing tumors with a relatively good prognosis. However, recurrences and metastases are a serious problem in advanced stages. Furthermore, progression from a well differentiated thyroid carcinoma to an aggressive anaplastic one is possible. The majority of differentiated thyroid carcinomas are sporadic but a few alleles increasing the cancer risk are known. One of them is the c.470 T > C (p.I157T, rs17879961) missense substitution in the CHEK2 gene. AIM OF THE STUDY: The aim of this study was to investigate whether this specific CHEK2 alteration, c.470 T > C, predisposes the Great Poland (Wielkopolska) population to thyroid cancer. METHODS: 602 differentiated thyroid carcinoma patients and 829 controls randomly selected from population were genotyped for the presence of the c.470C allele using pyrosequencing. Hardy-Weinberg Equilibrium (HWE) was tested for both groups by chi-square distribution and Fisher's exact test. The odds ratios (ORs), 95% confidence intervals (CIs), and p-values were calculated using the R software. RESULTS: The results of genotyping showed the presence of the c.470C allele in 51 patients with a frequency of 4.49%, while in a controls in 42 patients with a frequency of 2.53%. We demonstrated that in the Great Poland population the c.470C CHEK2 variant increases the risk of developing differentiated thyroid cancer almost twice (OR = 1.81, p = 0.004). The risk of papillary thyroid carcinoma in female patients homozygous for the c.470C allele was shown to increase almost 13-fold (OR = 12.81, p = 0.019). CONCLUSIONS: Identification of c.470C CHEK2 gene variant ought to be taken into account by healthcare policymakers. Future well-designed and larger population studies are of great value in confirming these findings. Moreover, a combination of genetic factors together with environmental exposures should also be considered.

CCND1 gene polymorphic variants in patients with differentiated thyroid carcinoma.

Alterations in the CCND1 gene affect the cell cycle and are frequently observed in a variety of cancers. While the most frequent mutations that occur in thyroid tumor tissue have been characterized, the genetic factors that predispose individuals to differentiated thyroid cancer (DTC) remain to be elucidated. The present study examined whether the CCND1 c.723G>A (rs9344; p.Pro241=) and c.669C>T (rs3862792; p.Phe223=) variants have an impact on DTC susceptibility. A cohort consisting of 652 patients diagnosed with DTC were analyzed and comapred with a reference group of 799 subjects from the general population. Pyrosequencing was used as the genotyping technique. In order to determine the statistical significance of differences observed in the genotypic and allelic frequencies between the compared groups, GraphPad Prism 4 was used. At the rs9344 locus in the DTC patients, a higher frequency of allele A [P=0.032; odds ratio (OR), 1.18; 95% confidence interval (CI), 1.014-1.361] and the AA homozygous genotype (P=0.028; OR, 1.41; 95% CI, 1.059-1.989) was observed compared with the control population group. The differences were stronger for papillary carcinomas (OR 1.45; 95% CI, 1.059-1.989), but were not significant in follicular tumors. No statistically significant differences were noted in the frequency of genotypes or alleles at the rs3862792 locus in the examined groups. The present findings indicate that the c.723A variant of the CCDN1 gene may be a susceptibility low penetrance allele in the development of papillary thyroid cancer in the population studied, however it does not impact on multifocality, metastatic ability or age at diagnosis. A cumulative effect of the analyzed CCND1 gene variants was also excluded.