Linkage analysis has identified four familial non-medullary thyroid carcinoma (FNMTC) susceptibility loci: fPTC/PRN (1p13.2-1q22), NMTC1 (2q21), MNG1 (14q32) and TCO (19p13.2). To date, there is no evidence for the involvement of genes from the RAS/RAF signalling pathway in FNMTC. The aim of our study was to evaluate the role of the four susceptibility loci, and RAS/RAF signalling pathway genes, in FNMTC. In total, 8 FNMTC families, and 27 thyroid lesions from family members (22 papillary thyroid carcinomas (PTCs): 11 classic, 10 of the follicular variant and 1 of the mixed variant; 4 follicular thyroid adenomas (FTAs) and 1 nodular goitre (NG)), were evaluated for the involvement of the four susceptibility regions, using linkage and loss of heterozygosity (LOH) analyses. BRAF and H-, N- and K-RAS mutations were also screened in the 27 lesions and patients. Linkage analysis in seven informative families showed no evidence for the involvement of any of the four candidate regions, supporting a genetic heterogeneity for FNMTC. Twenty tumours (74%), of which 18 were PTCs, showed no LOH at the four susceptibility loci. The remaining seven tumours (four PTCs, two FTAs and one NG) showed variable patterns of LOH. Fourteen tumours (52%) had somatic mutations: BRAF-V600E mutation was observed in 9 out of the 22 PTCs (41%); and H-RAS and N-RAS mutations were detected in 5 out of the 22 PTCs (23%). Our data suggest that the four candidate regions are not frequently involved in FNMTC and that the somatic activation of BRAF and RAS plays a role in FNMTC tumourigenesis.
Branca M Cavaco, Pedro F Batista, Carmo Martins, Ana Banito, Francisco do Rosário, Edward Limbert, Luís G Sobrinho, and Valeriano Leite
Stefan Karger, Carl Weidinger, Kerstin Krause, Sien-Yi Sheu, Thomas Aigner, Oliver Gimm, Kurt-Werner Schmid, Henning Dralle, and Dagmar Fuhrer
The forkhead box transcription factor FOXO3a has recently been identified as central mediator of the cellular response to oxidative stress inducing cell cycle arrest or apoptosis. The aim of our study was to investigate the regulation of FOXO3a in the thyroid and to determine whether alterations in FOXO3a activity occur in thyroid carcinogenesis. In vitro, we demonstrate that FOXO3a activity is negatively regulated by the PI3K/Akt cascade promoting increased phosphorylation and cytoplasmatic accumulation of FOXO3a with decreased transcription of the target genes p27kip (CDKN1B) and Bim (BCL2L11), but increased expression of GADD45A. By contrast, we show that H2O2 exposure activates FOXO3a in thyrocytes with JNK (MAPK8)-mediated nuclear accumulation of FOXO3a and increased expression of the cell cycle arrest genes p27kip and GADD45A. In vivo, we observed a marked cytoplasmatic accumulation of FOXO3a in differentiated thyroid cancers versus an exclusive nuclear accumulation in follicular adenoma and normal thyroid tissue. Moreover, this cytosolic accumulation of FOXO3a correlated with an increased phospho-Akt expression in thyroid malignancies and was accompanied by decreased expression of the FOXO targets p27kip and Bim and an increase in GADD45A mRNA expression in the thyroid cancers. Our data suggest FOXO3a as a novel player of cellular stress response in the thyroid, mediating the thyrocyte's fate either to survive or to undergo apoptosis. Furthermore, PI3K-dependent FOXO3a inactivation may be a novel pathomechanism for the escape from apoptosis in thyroid cancer cells, in particular in follicular thyroid carcinoma.
Federica Panebianco, Alyaksandr V Nikitski, Marina N Nikiforova, Cihan Kaya, Linwah Yip, Vincenzo Condello, Abigail I Wald, Yuri E Nikiforov, and Simion I Chiosea
ALK fusions are found in various tumors, including thyroid cancer, and serve as a diagnostic marker and therapeutic target. Spectrum and outcomes of ALK fusions found in thyroid nodules and cancer are not fully characterized. We report a series of 44 ALK-translocated thyroid neoplasms, including 31 identified preoperatively in thyroid fine-needle aspirates (FNA). The average patients’ age was 43 years (range, 8–76 years); only one with radiation history. All 19 resected thyroid nodules with ALK fusion identified preoperatively were malignant. Among nodules with known surgical pathology (n = 32), 84% were papillary thyroid carcinomas (PTCs) and 16% poorly differentiated thyroid carcinomas (PDTCs). PTCs showed infiltrative growth with follicular architecture seen exclusively (30%) or in combination with papillary and/or solid growth (37%). Tumor multifocality was seen in 10 (31%) PTC cases. Most PDTC had a well-differentiated PTC component. Lymph node metastases were identified in 10/18 (56%) patients with neck dissection. The most common ALK fusion partners were STRN (n = 22) and EML4 (n = 17). In five cases, novel ALK fusion partners were discovered. All five PDTCs carried STRN-ALK fusion. On follow-up, ten patients were free of disease at 2–108 months, whereas two patients with PDTC died of disease. In summary, ALK fusion-positive thyroid carcinomas are typically infiltrative PTC with common follicular growth, which may show tumor dedifferentiation associated with increased mortality. Compared to EML4-ALK, STRN-ALK may be more common in PDTC, and ~10% of ALK fusions occur to rare gene partners. When ALK fusion is detected preoperatively in FNA samples, malignancy should be expected.
J M Gómez, N Gómez, M Sahún, A Rafecas, C Villabona, and J Soler
Despite the usual excellent prognosis of differentiated thyroid carcinoma, some patients die because of disease. It has been speculated that lethal disease may have a better prognosis if patients are treated with extensive surgery plus 131I ablative treatment. We have analyzed a group of 223 patients with differentiated thyroid carcinoma treated under a uniform therapeutic protocol of surgery and followed for 3 to 17.7 years, in order to differentiate patients with a high and a low risk of mortality and the influence of therapy on survival rate.
The therapeutic protocol was as follows. If the diagnosis was papillary carcinoma, subtotal thyroidectomy was performed and cervical nodes were removed if they were suspicious for cancer. If the diagnosis was follicular carcinoma, a total thyroidectomy was performed. 131I was given in cases of patients who were more than 60 years old or who had extrathyroid disease or metastases in papillary carcinomas and in macroangioinvasive follicular carcinomas. In survival analysis, the event used as the end-point was death due to thyroid carcinoma and summarized by the Kaplan-Meier curve and the Mantel-Cox method.
We found three independent prognostic factors which determined mortality: over 60 years of age, tumor size larger than 6 cm and metastases. On the basis of these factors we identified two risk groups: a low-risk group (A), who had no risk factors, composed of 153 patients whose survival rate at 205 months was 100% and a high-risk group (B), who had one or more risk factors, composed of 55 patients whose survival rate at 213 months was 39.6%. Seventeen patients in this second group died from thyroid carcinoma. We therefore analyzed the effect of treatment in group B. Patients who had more extensive surgery had a similar survival rate to those who had less extensive surgery and 131I administration did not modify the survival rate.
These data support the idea that the identification of low-risk groups may facilitate a more rational approach to treatment of differentiated thyroid carcinoma, avoiding aggressive therapy in cases with a good prognosis.
Endocrine-Related Cancer (1997) 4 459-464
Xiaoli Liu, Justin Bishop, Yuan Shan, Sara Pai, Dingxie Liu, Avaniyapuram Kannan Murugan, Hui Sun, Adel K El-Naggar, and Mingzhao Xing
Mutations 1 295 228 C>T and 1 295 250 C>T (termed C228T and C250T respectively), corresponding to −124 C>T and −146 C>T from the translation start site in the promoter of the telomerase reverse transcriptase (TERT) gene, have recently been reported in human cancers, but not in thyroid cancers yet. We explored these mutations in thyroid cancers by genomic sequencing of a large number of primary tumor samples. We found the C228T mutation in 0 of 85 (0.0%) benign thyroid tumors, 30 of 257 (11.7%) papillary thyroid cancers (PTC), 9 of 79 (11.4%) follicular thyroid cancers (FTC), 3 of 8 (37.5%) poorly differentiated thyroid cancers (PDTC), 23 of 54 (42.6%) anaplastic thyroid cancers (ATC), and 8 of 12 (66.7%) thyroid cancer cell lines. The C250T mutation was uncommon, but mutually exclusive with the C228T mutation, and the two mutations were collectively found in 11 of 79 (13.9%) FTC, 25 of 54 (46.3%) ATC, and 11 of 12 (91.7%) thyroid cancer cell lines. Among PTC variants, the C228T mutation was found in 4 of 13 (30.8%) tall-cell PTC (TCPTC), 23 of 187 (12.3%) conventional PTC, and 2 of 56 (3.6%) follicular variant PTC samples. No TERT mutation was found in 16 medullary thyroid cancer samples. The C228T mutation was associated with the BRAF V600E mutation in PTC, being present in 19 of 104 (18.3%) BRAF mutation-positive PTC vs 11 of 153 (7.2%) the BRAF mutation-negative PTC samples (P=0.0094). Conversely, BRAF mutation was found in 19 of 30 (63.3%) C228T mutation-positive PTC vs 85 of 227 (37.4%) C228T mutation-negative PTC samples (P=0.0094). We thus for the first time, to our knowledge, demonstrate TERT promoter mutations in thyroid cancers, that are particularly prevalent in the aggressive thyroid cancers TCPTC, PDTC, ATC and BRAF mutation-positive PTC, revealing a novel genetic background for thyroid cancers.
Aruna V Krishnan and David Feldman
Calcitriol, the hormonally active form of vitamin D, exerts multiple anti-proliferative and pro-differentiating actions including cell cycle arrest and induction of apoptosis in many malignant cells, and the hormone is currently being evaluated in clinical trials as an anti-cancer agent. Recent research reveals that calcitriol also exhibits multiple anti-inflammatory effects. First, calcitriol inhibits the synthesis and biological actions of pro-inflammatory prostaglandins (PGs) by three mechanisms: i) suppression of the expression of cyclooxygenase-2, the enzyme that synthesizes PGs; ii) up-regulation of the expression of 15-hydroxyprostaglandin dehydrogenase, the enzyme that inactivates PGs; and iii) down-regulation of the expression of PG receptors that are essential for PG signaling. The combination of calcitriol and nonsteroidal anti-inflammatory drugs results in a synergistic inhibition of the growth of prostate cancer (PCa) cells and offers a potential therapeutic strategy for PCa. Second, calcitriol increases the expression of mitogen-activated protein kinase phosphatase 5 in prostate cells resulting in the subsequent inhibition of p38 stress kinase signaling and the attenuation of the production of pro-inflammatory cytokines. Third, calcitriol also exerts anti-inflammatory activity in PCa through the inhibition of nuclear factor-κB signaling that results in potent anti-inflammatory and anti-angiogenic effects. Other important direct effects of calcitriol as well as the consequences of its anti-inflammatory effects include the inhibition of tumor angiogenesis, invasion, and metastasis. We hypothesize that these anti-inflammatory actions, in addition to the other known anti-cancer effects of calcitriol, play an important role in its potential use as a therapeutic agent for PCa. Calcitriol or its analogs may have utility as chemopreventive agents and should be evaluated in clinical trials in PCa patients with early or precancerous disease.
G Riesco-Eizaguirre, P Gutiérrez-Martínez, M A García-Cabezas, M Nistal, and P Santisteban
The oncogene BRAFV600E is the most frequent genetic event in papillary thyroid carcinoma (PTC) but its prognostic impact still remains to be elucidated. We evaluated a representative series of 67 individuals with PTC who underwent total thyroidectomy. BRAF-positive tumours correlated with early recurrences (32% vs 7.6%; P=0.02) during a median postoperative follow-up period of 3 years. Interestingly, within the recurrences, a significant majority had negative radioiodine (131I) total body scans, predicting a poorer outcome as treatment with 131I is not effective. This last observation led us to investigate the role of BRAFV600E and the MEK-ERK pathway in thyroid dedifferentiation, particularly in Na+/I− symporter (NIS) impairment, as this thyroid-specific plasma membrane glycoprotein mediates active transport of I− into the thyroid follicular cells. A subset of 60 PTC samples was evaluated for NIS immunoreactivity and, accordingly, we confirmed a significant low NIS expression and impaired targeting to membranes in BRAF-positive samples (3.5% vs 30%; P=0.005). Furthermore, experiments with differentiated PCCl3 thyroid cells demonstrated that transient expression of BRAFV600E sharply impaired both NIS expression and targeting to membrane and, surprisingly, this impairment was not totally dependent on the MEK-ERK pathway. We have concluded that BRAFV600E is a new prognostic factor in PTC that correlates with a high risk of recurrences and less differentiated tumours due to the loss of NIS-mediated 131I uptake.
Claudia Bozza, Fabio Puglisi, Matteo Lambertini, Etin-Osa Osa, Massimo Manno, and Lucia Del Mastro
Breast cancer is the most common invasive cancer in women of reproductive age. In young women, chemotherapy may induce amenorrhea: it is still uncertain how to assess menopausal status in these patients despite the importance of its definition for choosing appropriate endocrine treatment. In the development of sensitive biomarkers for fertility and ovarian reserve, anti-Müllerian hormone (AMH) is considered a promising marker of ovarian reserve. The clearest data regarding a clinical use of AMH are related to the measurement of the ovarian pool in women who undergo IVF: the available data, also in breast cancer patients, seem to suggest that AMH measurement, before gonadotropin administration, can be a useful marker for the prediction of women at risk for poor-response or no response to ovarian stimulation. The utility of AMH as a potential marker of chemotherapy-induced ovarian follicular depletion and an early plasma marker of chemotherapy-induced gonadal damage has been evaluated both in young women after treatment for cancer in childhood and in young survivors of hematological malignancies and solid tumors. Several studies have demonstrated a potential utility of AMH, inhibin, or follicle-stimulating factor as biomarkers predicting infertility risk in breast cancer patients, but the studies conducted so far are not conclusive. Further studies are needed in order to define the regimen-specific action of chemotherapy on AMH levels, the percentage of post-treatment recovery of plasma levels of the hormone, and the relationship between menopausal status and AMH.
Brian Hung-Hin Lang, Chung-Yau Lo, Wai-Fan Chan, King-Yin Lam, and Koon-Yat Wan
A number of risk-group stratification or staging systems have been found useful at stratifying patients with differentiated thyroid carcinoma into risk groups. Those identified as high risk could be subjected to more aggressive treatment, while those at low risk could be spared of such treatment. However, the best stratification system in patients with follicular thyroid carcinoma (FTC) remains unclear. Through a comprehensive MEDLINE search from 1965 to 2005, a total of 18 different staging systems were identified in the literature and 14 of them were applicable to 171 patients, with FTC managed at our institution from 1961 to 2001. Cancer-specific survivals (CSS) were calculated by Kaplan–Meier method and were compared by log-rank test. Using Cox proportional hazards analysis, the relative importance of each staging system in determining CSS was calculated by the proportion of variation in survival time explained (PVE). CSS were predicted by 13 out of the 14 staging systems significantly (P < 0.001). The three highest ranked staging systems by PVE were the new American Joint Commitee on Cancer/Union Internationale Centre le Cancer 6th edition, tumour, node, metastases (TNM; 22.4), followed by the Clinical Class (21.2) and the metastases, age, completeness of resection, invasion, size (MACIS; 20.4). In conclusion, 13 out of the 14 presently available staging systems predicted CSS significantly in FTC. When predictability was measured by PVE, the TNM system was found to have the best predictability and thus, should be the stratification system of choice for FTC in the future.
Giuseppe Palladino, Tiziana Notarangelo, Giuseppe Pannone, Annamaria Piscazzi, Olga Lamacchia, Lorenza Sisinni, Girolamo Spagnoletti, Paolo Toti, Angela Santoro, Giovanni Storto, Pantaleo Bufo, Mauro Cignarelli, Franca Esposito, and Matteo Landriscina
Tumor necrosis factor receptor-associated protein 1 (TRAP1) is a heat shock protein 90 (HSP90) molecular chaperone upregulated in several human malignancies and involved in protection from apoptosis and drug resistance, cell cycle progression, cell metabolism and quality control of specific client proteins. TRAP1 role in thyroid carcinoma (TC), still unaddressed at present, was investigated by analyzing its expression in a cohort of 86 human TCs and evaluating its involvement in cancer cell survival and proliferation in vitro. Indeed, TRAP1 levels progressively increased from normal peritumoral thyroid gland, to papillary TCs (PTCs), follicular variants of PTCs (FV-PTCs) and poorly differentiated TCs (PDTCs). By contrast, anaplastic thyroid tumors exhibited a dual pattern, the majority being characterized by high TRAP1 levels, while a small subgroup completely negative. Consistently with a potential involvement of TRAP1 in thyroid carcinogenesis, TRAP1 silencing resulted in increased sensitivity to paclitaxel-induced apoptosis, inhibition of cell cycle progression and attenuation of ERK signaling. Noteworthy, the inhibition of TRAP1 ATPase activity by pharmacological agents resulted in attenuation of cell proliferation, inhibition of ERK signaling and reversion of drug resistance. These data suggest that TRAP1 inhibition may be regarded as potential strategy to target specific features of human TCs, i.e., cell proliferation and resistance to apoptosis.