Accumulation of p27(kip1) is associated with cyclin D3 overexpression in the oxyphilic (Hurthle cell) variant of follicular thyroid carcinoma.

BACKGROUND: The down regulation of protein p27(kip1) (p27) in most cases of thyroid cancer has relevant diagnostic and prognostic implications. However, the oxyphilic (Hurthle cell) variant of follicular thyroid carcinoma expresses more p27 than benign oxyphilic lesions do. AIM: To evaluate the mechanism underlying this difference in expression of p27. METHODS: Because high levels of cyclin D3 lead to p27 accumulation in cell lines and clinical samples of thyroid cancer, the immunocytochemical pattern of cyclin D3 in oxyphilic (n = 47) and non-oxyphilic (n = 70) thyroid neoplasms was investigated. RESULTS: In the whole study sample, there was a significant correlation between p27 and cyclin D3 expression (Spearman's r: 0.64; p<0.001). The expression of cyclin D3 and p27 was significantly higher in the oxyphilic variant of follicular carcinomas than in non-oxyphilic carcinomas (p<0.001). In the former, cyclin D3 overexpression and p27 accumulation were observed in a median of 75% and 55% of cells, respectively. In co-immunoprecipitation experiments, the level of p27-bound cyclin D3 was much higher in oxyphilic neoplasias than in normal thyroids and other thyroid tumours. CONCLUSION: These results show that increased p27 expression in the oxyphilic (Hurthle cell) variant of follicular thyroid carcinoma results from cyclin D3 overexpression.

Myocardial contractility and total arterial stiffness in patients with overt hyperthyroidism: acute effects of beta1-adrenergic blockade.

OBJECTIVES: To ascertain whether myocardial contractility and total arterial stiffness are significantly altered in human thyrotoxicosis, and to what extent they are affected by acute beta(1)-adrenergic blockade. METHODS: Doppler-echocardiography was used to assess left ventricular (LV) structure and function, hemodynamics and total arterial stiffness in untreated overt hyperthyroid patients before and 2 h after 5 mg bisoprolol given orally compared with age- and sex-matched healthy euthyroid controls. RESULTS: Compared with controls, untreated patients (n=20) had a higher heart rate (HR) and LV stroke index (SI), which were associated with higher pulse pressure (PP), larger LV end-diastolic volume index (EDVI, an index of preload,+11%, P<0.05), marginally increased stress-corrected LV midwall fractional shortening (MWS, an index of myocardial contractility,+5%; P=0.066), and shorter isovolumic relaxation time (IVRT). These changes resulted in a higher cardiac index (CI) and a lower systemic vascular resistance (SVR), which were associated with fairly normal mean blood pressure (BP) but higher PP/stroke volume (an index of total arterial stiffness,+29%; P<0.01). After bisoprolol, compared with controls, the randomly treated patients (n=10) had comparable HR but additionally increased SI; PP remained enhanced, EDVI was further enlarged (+26%, P<0.001), stress-corrected MWS was substantially unchanged, and IVRT remained shorter. Overall, these effects attenuated the high-output state, which was associated with normalization of PP/stroke volume without changes of mean BP. CONCLUSIONS: In human overt hyperthyroidism, myocardial contractility does not play a major role in increasing LV performance, which is instead predominantly sustained by increased preload with enhanced LV diastolic function. In addition, human thyrotoxicosis is associated with increased total arterial stiffness despite fairly normal mean BP. In this scenario, acute beta(1)-adrenergic blockade blunts the cardiovascular hyperkinesia predominantly by slowing HR - a process that is associated with normalization of total arterial stiffness.

Long-term efficacy of doxazosin plus atenolol in the management of severe and sustained arterial hypertension and reversibility of the cardiac damage induced by chronic cathecolamine excess. A case report in a young girl with recurrent, functioning paraganglioma.

Herein we report on a young girl with recurrent, functioning paraganglioma of the organ of Zuckerkandl and severe and sustained arterial hypertension (systolic pressure >200, diastolic pressure >120 mmHg); with evidence of cardiac damage induced by chronic cathecolamine excess. She promptly and steadily improved after the institution of doxazosin (6 mg/day) plus atenolol (50 mg bid) treatment. This case demonstrates that a correct therapeutic strategy in the long-term management of patients with inoperable catecholamine-producing neuroendocrine tumors (pheochromocytomas and paragangliomas) can maintain arterial pressure in the normal range and reverse the cardiac damage induced by chronic cathecolamine excess.

Quantitative assessment of oxyphilic cell lesions of the thyroid gland on fine needle aspiration samples.

OBJECTIVE: To assess the possible contribution by a multiparametric quantitative approach to the cytologic diagnosis of oxyphilic cell (OC) thyroid lesions. STUDY DESIGN: Ten cases of chronic lymphocytic (Hashimoto) thyroiditis and 10 nodular goiters containing oxyphilic cells plus 20 cases of tumors subsequently classified as oxyphilic cell adenomas (10 cases) or oxyphilic cell well-differentiated carcinomas (10 cases) were evaluated. The study was performed on May-Grünwald-Giemsa-stained smears for planimetric measurements. The same smears were destained and Feulgen restained for densitometric measurements. The latter were performed using static cytometry equipment measuring 100 and 20-30 lymphocytes per case for the determination of integrated optical density (IOD). The following parameters were considered: nuclear area, perimeter, maximum diameter, form ELL, form PE, IOD, 5c exceeding rate (5cER) and visual classification of histograms as euploid, polyploid and aneuploid. RESULTS: Mean nuclear area of carcinomas was smaller than that of adenomas, goiter and thyroiditis. Nuclear area was larger in adenomas than in other benign lesions and carcinomas. All the other planimetric parameters were similar in the lesions examined. Four carcinomas and three adenomas were aneuploid, and all the rest were euploid. All the cases of thyroiditis and goiter were euploid or polyploid; four thyroiditis cases showed polyploid histograms and 5cER values > 1. CONCLUSION: Morphometric and densitometric procedures have a limited role in the discrimination of OC lesions, but small nuclear area values may be useful in distinguishing OC carcinoma from other lesions. The role of densitometry seems even more limited because aneuploid histograms may be found among adenomas and carcinomas. Further studies are needed to explain polyploidy and 5cER > 1 in Hashimoto thyroiditis.

Cardiovascular effects of short-term growth hormone hypersecretion.

Many studies have shown that acromegaly has relevant effects on cardiovascular system, but few data are available regarding the effects of short-term acromegaly on heart morphology and function. These data would help to clarify the natural history of acromegalic disease and could provide new insight into the mechanisms of GH action on the human heart. Therefore, we studied by Doppler echocardiography a group of 10 young subjects strictly selected as having short-term (<5 yr) uncomplicated acromegaly. The results of this study have shown that shortterm acromegaly is characterized by significantly increased left ventricular mass (P<0.005), with normal relative wall thickness, associated with Doppler indices of diastolic function in the normal range. Furthermore, stroke index and cardiac index were significantly enhanced in the patient group (P<0.01 and P<0.001, respectively), whereas systemic vascular resistance was significantly reduced (P<0.001). In conclusion, our study shows that short-term acromegaly significantly affects the heart, but, at variance with long-term disease, it is characterized by increased left ventricular mass, with eccentric remodeling and normal diastolic function. Moreover, short-term acromegaly induces a high cardiac output state with reduction of systemic vascular resistance.

Endogenous subclinical hyperthyroidism affects quality of life and cardiac morphology and function in young and middle-aged patients.

To determine the clinical impact of endogenous subclinical hyperthyroidism, specific symptoms and signs of thyroid hormone excess and quality of life were assessed in 23 patients (3 males and 20 females; mean age, 43 +/- 9 yr) and 23 age-, sex-, and lifestyle-matched normal subjects by using the Symptoms Rating Scale and the Short Form 36 Health Survey questionnaires. Because the heart is one of the main target organs of the thyroid hormone, cardiac morphology and function were also investigated by means of standard 12-lead electrocardiogram (ECG), 24-h Holter ECG, and complete Doppler echocardiography. Stable endogenous subclinical hyperthyroidism had been diagnosed in all patients at least 6 months before the study (TSH, 0.15 +/- 0.1 mU/L; free T(3), 6.9 +/- 1.1, pmol/L; free T(4), 17.2 +/- 2.3, pmol/L). Fifteen patients were affected by multinodular goiter, and eight patients by autonomously functioning thyroid nodule. The mean Symptoms Rating Scale score (9. 8 +/- 5.5 vs. 4.3 +/- 2.2, P: < 0.001) and both the mental (36.1 +/- 9.5 vs. 50.0 +/- 8.5, P: < 0.001) and physical (42.6 +/- 8.0 vs. 55. 6 +/- 4.1, P: < 0.001) component scores of Short Form 36 Health Survey documented a significant prevalence of specific symptoms and signs of thyroid hormone excess and notable impairment of quality of life in patients. Holter ECG showed a higher prevalence of atrial premature beats in endogenous subclinical hyperthyroid patients than in the controls, but the difference was not statistically significant, although the average heart rate was significantly increased in the patients (P: < 0.001). An increase of left ventricular mass (162 +/- 24 vs. 132 +/- 22 g, P: < 0.001) due to the increase of septal (P: = 0.025) and posterior wall (P: = 0.004) thickness was observed in patients. Systolic function was enhanced in patients as shown by the significant increase of both fractional shortening (P: = 0.005) and mean velocity of heart rate-adjusted circumferential fiber shortening (P: = 0.036). The Doppler parameters of diastolic function were significantly impaired in the patients as documented by the reduced early to late ratio of the transmitral flow velocities (P: < 0.001) and the prolonged isovolumic relaxation time (P: = 0.006). These data indicate that endogenous subclinical hyperthyroidism has a relevant clinical impact and that it affects cardiac morphology and function. Moreover, they suggest that treatment of persistent endogenous subclinical hyperthyroidism should be considered also in young and middle-aged patients to attenuate specific symptoms and signs of thyroid hormone excess, ameliorate the quality of life, and avoid the consequences to the heart of long exposure to a mild excess of thyroid hormone.

[Effects of chronic subclinical hyperthyroidism from levothyroxine on cardiac morphology and function]. / Effetti dell'ipertiroidismo subclinico cronico da terapia con levotiroxina su morfologia e funzione cardiaca.

BACKGROUND: Thyroid hormones greatly affect the cardiovascular system. Although the effects of overt hyperthyroidism on the cardiovascular system have been diffusely studied, only in the last years the effects of subclinical hyperthyroidism on the heart have been investigated. Subclinical hyperthyroidism is a symptomatic or asymptomatic condition with an absent response of thyrotropin (TSH) to thyrotropin-releasing hormone in the presence of normal serum levels of thyroid hormones for the general population, though supraoptimal for the individual. The more frequent causes of endogenous subclinical hyperthyroidism are multinodular goiter, toxic, adenoma and Graves's disease, whereas the exogenous causes are induced by levothyroxine (LT4) therapy used to suppress TSH in patients with nontoxic goiter and differentiated thyroid cancer. This paper reports our experience derived from the study of 60 patients with subclinical hyperthyroidism due to TSH-suppressive therapy with LT4 compared to normal subjects. METHODS: Patients (9 males and 51 females, mean age 39 +/- 10 years) were studied by complete Doppler echocardiography, standard and 24 hour ECG Holter monitoring, exercise test with cycloergometer, and radionuclide ventriculography at rest and during fixed workload (75 W). RESULTS: Holter monitoring showed a significant increase in mean 24 hour heart rate (80 +/- 10 vs 70 +/- 9 b/min, p < 0.001) and supraventricular arrhythmias (42 vs 12 patients, p < 0.003). Echocardiography showed an increase in left ventricular mass index (94 +/- 13 vs 80 +/- 18 g/m2, p < 0.001) due to increased septal and posterior wall thickness. At rest, echocardiographic indices of systolic function (fractional shortening and mean corrected velocity of circumferential fiber shortening) were higher in patients than in controls (fractional shortening 40 +/- 6 vs 34 +/- 4%, p < 0.001; mean corrected velocity of circumferential fiber shortening 1.23 +/- 0.17 vs 1.05 +/- 0.14 circ/s, p < 0.001), while the Doppler indices of diastolic function were significantly impaired as documented by the reduced E/A ratio (1.18 +/- 0.3 vs 1.8 +/- 0.5, p < 0.001) and the prolonged isovolumic relaxation time (94 +/- 13 vs 78 +/- 12 ms, p < 0.001). Exercise tolerance was also significantly impaired in patients with subclinical hyperthyroidism: maximal exercise time (6.4 +/- 0.7 vs 9.4 +/- 1.4 min, p < 0.001) and peak workload (81 +/- 11 vs 121 +/- 17 W, p < 0.001) were significantly reduced and radionuclide ventriculography showed a decrease in ejection fraction during exercise (from 62 +/- 7 to 53 +/- 8%, p < 0.002). CONCLUSIONS: Persistent subclinical hyperthyroidism by TSH-suppressive doses of LT4 significantly affects heart morphology and function. Thus, we suggest that a complete suppression of TSH must be recommended only in patients with differentiated thyroid cancer, while in patients with begin thyroid disease it could be sufficient to maintain subnormal TSH levels.

Left ventricular diastolic dysfunction in patients with subclinical hypothyroidism.

Although subclinical hypothyroidism is frequently diagnosed, the decision to institute a substitutive therapy with L-T4 remains controversial. Because the cardiovascular system is considered a main target for the action of thyroid hormone, we investigated whether subclinical hypothyroidism induces cardiovascular abnormalities. Twenty-six patients (mean age, 36 +/- 12 yr) were evaluated by Doppler-echocardiography, whereas a subgroup of 10 patients, randomly selected, were reevaluated after 6 months of L-T4 substitutive therapy (mean dose, 68 microg daily). Thirty subjects (matched for age, sex, and body surface area) served as controls. Mean plasma TSH was significantly higher in patients (P < 0.001), whereas mean serum free T4 and free T3 concentrations, although in the normal range, were significantly lower (P < 0.001 and P < 0.005, respectively). Blood pressure and heart rate did not differ from control values. Echocardiogram examination showed no abnormalities of the left ventricular morphology and a slight, but not significant, reduction in the systolic function in the patient group. In contrast, Doppler-derived indices of diastolic function showed significant prolongation of the isovolumic relaxation time (94 +/- 13 vs. 84 +/- 8 msec; P < 0.001), increased A wave (55 +/- 13 vs. 48 +/- 9 cm/sec; P < 0.05), and reduced early diastolic mitral flow velocity/late diastolic mitral flow velocity ratio (1.4 +/- 0.3 vs. 1.7 +/- 0.3; P < 0.001). In the subgroup of 10 patients, thyroid hormone profile was normalized by 6 months of L-T4 substitutive therapy, whereas no changes were observed in the left ventricular morphology. Systolic function was significantly enhanced, as compared with pretreatment values (P < 0.01) but did not differ from control values. Also, systemic vascular resistance was significantly decreased by L-T4 replacement therapy. Assessment of diastolic function showed significant shortening of isovolumic relaxation time (77 +/- 15 vs. 91 +/- 8; P < 0.05), reduction of A wave (51 +/- 13 vs. 60 +/- 12; P < 0.01), and increase of early diastolic mitral flow velocity/late diastolic mitral flow velocity ratio (1.7 +/- 0.4 vs. 1.3 +/- 0.3; P < 0.001). These indices, however, were comparable with those of control subjects. These findings indicate that subclinical hypothyroidism affects diastolic function and that this abnormality may be reversed by L-T4 substitutive therapy.

Doxorubicin-induced cardiomyopathy treated with carvedilol.

Even today, heart failure due to doxorubicin-induced dilated cardiomyopathy seems to have a poor prognosis, as it is often irreversible and relatively unresponsive to standard medical treatment. This paper describes the first case of a patient complaining of severe symptoms of congestive heart failure due to doxorubicin-induced dilated cardiomyopathy unresponsive to standard medical treatment (digoxin, diuretics, and angiotensin-converting enzyme inhibitor), who showed complete clinical recovery and significant improvement of left ventricular dysfunction after carvedilol treatment. It also illustrates the possibility that carvedilol may be a first-choice drug for the treatment of this disease.