Insulin receptor isoform A, a newly recognized, high-affinity insulin-like growth factor II receptor in fetal and cancer cells

Insulin-like growth factor II (IGF-II) is a peptide growth factor that is homologous to both insulin-like growth factor I (IGF-I) and insulin and plays an important role in embryonic development and carcinogenesis. IGF-II is believed to mediate its cellular signaling via the transmembrane tyrosine kinase type 1 insulin-like growth factor receptor (IGF-I-R), which is also the receptor for IGF-I. Earlier studies with both cultured cells and transgenic mice, however, have suggested that in the embryo the insulin receptor (IR) may also be a receptor for IGF-II. In most cells and tissues, IR binds IGF-II with relatively low affinity. The IR is expressed in two isoforms (IR-A and IR-B) differing by 12 amino acids due to the alternative splicing of exon 11. In the present study we found that IR-A but not IR-B bound IGF-II with an affinity close to that of insulin. Moreover, IGF-II bound to IR-A with an affinity equal to that of IGF-II binding to the IGF-I-R. Activation of IR-A by insulin led primarily to metabolic effects, whereas activation of IR-A by IGF-II led primarily to mitogenic effects. These differences in the biological effects of IR-A when activated by either IGF-II or insulin were associated with differential recruitment and activation of intracellular substrates. IR-A was preferentially expressed in fetal cells such as fetal fibroblasts, muscle, liver and kidney and had a relatively increased proportion of isoform A. IR-A expression was also increased in several tumors including those of the breast and colon. These data indicate, therefore, that there are two receptors for IGF-II, both IGF-I-R and IR-A. Further, they suggest that interaction of IGF-II with IR-A may play a role both in fetal growth and cancer biology.

Insulin receptor activation by IGF-II in breast cancers: evidence for a new autocrine/paracrine mechanism

IGF-II, produced by breast cancer epithelial and stromal cells, enhances tumor growth by activating the IGF-I receptor (IGF-I-R) via autocrine and paracrine mechanisms. Previously we found that the insulin receptor (IR), which is related to the IGF-I-R, is overexpressed in breast cancer cells. Herein, we find that, in breast cancer the IR is activated by IGF-II. In eight human breast cancer cell lines studied there was high affinity IGF-II binding to the IR, with subsequent IR activation. In these lines, IGF-II had a potency up to 63% that of insulin. In contrast, in non malignant human breast cells, IGF-II was less than 1% potent as insulin. Via activation of the IR tyrosine kinase IGF-II stimulated breast cancer cell growth. Moreover, IGF-II also activated the IR in breast cancer tissue specimens; IGF-II was 10-100% as potent as insulin. The IR occurs in two isoforms generated by alternative splicing of exon 11; these isoforms are IR-A (Ex11-) and IR-B (Ex11+). IR-A was predominantly expressed in breast cancer cells and specimens and the potency of IGF-II was correlated to the expression of this isoform (P<0.0001). These data indicate, therefore, that the IR-A, which binds IGF-II with high affinity, is predominantly expressed in breast cancer cells and represents a new autocrine/paracrine loop involved in tumor biology.

BRAF(V600E) mutation and the biology of papillary thyroid cancer

BRAF((V600E)) mutation is the most frequent genetic alteration in papillary thyroid carcinomas (PTCs) that are 80-90% of all thyroid cancers. We evaluated the relationship between BRAF((V600E)) and tumor, host, and environmental factors in PTCs from all geographical areas of Sicily. By PCR, BRAF((V600E)) was investigated in a series of 323 PTCs diagnosed in 2002-2005. The correlation between clinicopathological tumor, host, and environmental characteristics and the presence of BRAF((V600E)) were evaluated by both univariate and multivariate analyses. BRAF((V600E)) was found in 38.6% PTCs, with a 52% frequency in the classical PTCs and 26.4% in the tall cell variant. Univariate analysis indicated that BRAF((V600E)) was associated with greater tumor size (P=0.0048), extra-thyroid invasion (P<0.0001), and cervical lymph nodal metastases (P=0.0001). Multivariate logistic regression analysis confirmed that BRAF((V600E)) was an independent predictor of extra-thyroid invasion (P=0.0001) and cervical lymph nodal metastasis (P=0.0005). The association between BRAF((V600E)) and extra-thyroid invasion was also found in micro-PTCs (P=0.006). In 60 classical PTCs, BRAF((V600E)) was positively correlated with matrix metalloproteinase-9 expression (P=0.0047), suggesting a possible mechanism for BRAF((V600E)) effect on PTC invasiveness. No association was found between BRAF((V600E)) and patient age, gender, or iodine intake. In contrast, a strong association was found with residency in Eastern Sicily (P<0.0001 compared with Western Sicily). These results indicate that BRAF((V600E)) mutation is a marker of aggressive disease in both micro- and macro-PTCs. Moreover, for the first time, a possible link between BRAF((V600E)) mutation and environmental carcinogens is suggested.

Clinical and molecular mechanisms favoring cancer initiation and progression in diabetic patients

Cancer incidence and mortality are higher among diabetic patients. This review examines the mechanisms, both general and site-specific, for this increase. Hyperglycemia and hyperinsulinemia, which are the major abnormalities that characterize diabetes, can promote cancer via both independent and synergic mechanisms. Insulin is both a metabolic hormone and a growth factor that promotes cell proliferation. When insulin levels are increased due to either insulin resistance or insulin treatment, their mitogenic effect is more marked in malignant cells that frequently overexpress the insulin receptor and, more specifically, its A isoform that has predominant mitogenic activity. Hyperglycemia provides energy for malignant cell proliferation and, via the peculiar energy utilization of cancer cells, favors cancer growth and neoangiogenesis. Additionally, diabetes-associated obesity has cancer-promoting effects due to mechanisms that are specific to excess fat cells (such as increased peripheral estrogens, increased pro-mitogen cytokines and growth factors). Also fat-associated chronic inflammation can favor cancer via the cell damage caused by reactive oxygen species (ROS) and via the production of inflammatory cytokines and transcription factors that stimulate cancer growth and invasiveness. Finally, the multiple drugs involved in the treatment of diabetes can also play a role. Diabetes-associated comorbidities, tissue-specific inflammation, and organ-specific dysfunctions can explain why the risk of cancer can differ by tissue type among diabetic patients. The increased risk of cancer-related mortality is moderate among individual patients with diabetes (RR = 1.25), but the pandemic nature of the disease means that a considerable number of lives could be spared through a better understanding of the factors associating diabetes and cancer.

p53 family proteins in thyroid cancer

At variance with other human malignancies, p53 mutations are not frequent in thyroid cancer and are believed to be responsible mainly for cancer progression to poorly differentiated and aggressive phenotype. p63 and p73, two proteins with a high degree of homology with p53, are overexpressed in thyroid cancer, but their role in cancer initiation or progression is controversial. Regulation of p53 family protein function depends on: (1) the balance between the expression of transcriptionally active (p53, TAp63, and TAp73) and inactive isoforms (DeltaNp63 and DeltaNp73); (2) their interaction and competition at DNA-responsive elements; (3) their interaction with regulatory proteins, either inhibitory or activating. In thyroid cancer, therefore, although mutations of the p53 oncosuppressor protein family are rare, other mechanisms are present, including aberrant expression of p53 family dominant negative isoforms, up-regulation of inhibitory proteins, and functional inhibition of activating proteins. The overall result is a defective oncosuppressor activity. These inactivating mechanisms may be present in the early stages of thyroid cancer and in different cancer histotypes. A better understanding of this complex network may not only ameliorate our comprehension of cancer biology, but also open the possibility of innovative diagnostic procedures and the development of targeted therapies.

Tyrosine kinase inhibitor STI571 enhances thyroid cancer cell motile response to Hepatocyte Growth Factor

The Hepatocyte Growth Factor (HGF) and its receptor Met are physiological regulators of cell migration. HGF and Met have also been implicated in tumor progression and metastasis. We show here that the tyrosine kinase inhibitor STI571 has a stimulatory effect on HGF-induced migration and branching morphogenesis in thyroid cancer but not in primary or immortalized thyroid epithelial cells. These stimulatory effects of STI571 are observed at a concentration that is clinically relevant. The STI571-enhanced motile response can be correlated with an increase in the Met receptor tyrosine phosphorylation as well as ERK and Akt activation by HGF. Interestingly, one of the targets of STI571, namely the c-Abl tyrosine kinase, is activated by HGF and is recruited at the migrating edge of thyroid cancer cells. These data suggests that c-Abl and/or STI571-inhibited tyrosine kinases can negatively regulate the Met receptor to restrain the motile response in thyroid cancer cells.

Relationship between betacoronaviruses and the endocrine system: a new key to understand the COVID-19 pandemic-A comprehensive review

BACKGROUND

A new harmful respiratory disease, called COVID-19 emerged in China in December 2019 due to the infection of a novel coronavirus, called SARS-Coronavirus 2 (SARS-CoV-2), which belongs to the betacoronavirus genus, including SARS-CoV-1 and MERS-CoV. SARS-CoV-2 shares almost 80% of the genome with SARS-CoV-1 and 50% with MERS-CoV. Moreover, SARS-CoV-2 proteins share a high degree of homology (approximately 95%) with SARS-CoV-1 proteins. Hence, the mechanisms of SARS-Cov-1 and SARS-Cov-2 infection are similar and occur via binding to ACE2 protein, which is widely distributed in the human body, with a predominant expression in endocrine tissues including testis, thyroid, adrenal and pituitary.

PURPOSE

On the basis of expression pattern of the ACE2 protein among different tissues, similarity between SARS-Cov-1 and SARS-Cov-2 and the pathophysiology of COVID-19 disease, we aimed at discussing, after almost one-year pandemic, about the relationships between COVID-19 infection and the endocrine system. First, we discussed the potential effect of hormones on the susceptibility to COVID-19 infection; second, we examined the evidences regarding the effect of COVID-19 on the endocrine system. When data were available, a comparative discussion between SARS and COVID-19 effects was also performed.

METHODS

A comprehensive literature search within Pubmed was performed. This review has been conducted according to the PRISMA statements.

RESULTS

Among 450, 100 articles were selected. Tissue and vascular damages have been shown on thyroid, adrenal, testis and pituitary glands, with multiple alterations of endocrine function.

CONCLUSION

Hormones may affect patient susceptibility to COVID-19 infection but evidences regarding therapeutic implication of these findings are still missing. SARS and COVID-19 may affect endocrine glands and their dense vascularization, impairing endocrine system function. A possible damage of endocrine system in COVID-19 patients should be investigated in both COVID-19 acute phase and recovery to identify both early and late endocrine complications that may be important for patient's prognosis and well-being after COVID-19 infection.

Insulin-stimulated cell growth in insulin receptor substrate-1-deficient ZR-75-1 cells is mediated by a phosphatidylinositol-3-kinase-independent pathway

In many human breast cancers and cultured cell lines, insulin receptor expression is elevated, and insulin, via its own insulin receptor, can stimulate cell growth. It has recently been demonstrated that the enzyme phosphatidylinositol-3-kinase (PI3-K) mediates various aspects of insulin receptor signaling including cell growth. In order to understand the mechanisms for insulin-stimulated cell growth in human breast cancer, we measured insulin-stimulable PI3-K activity in a non-transformed breast epithelial cell line, MCF-10A, and in two malignantly transformed cell lines, ZR-75-1 and MDA-MB157. All three cell lines express comparable amounts of insulin receptors whose tyrosine autophosphorylation is increased by insulin, and in these cell lines insulin stimulates growth. In MDA-MB157 and MCF-10A cells, insulin stimulated PI3-K activity three- to fourfold. In ZR-75-1 cells, however, insulin did not stimulate PI3-K activity. In ZR-75-1 cells PI3-K protein was present, and its activity was stimulated by epidermal growth factor, suggesting that there might be a defect in insulin receptor signaling upstream of PI3-K and downstream of the insulin receptor. Next, we studied insulin receptor substrate-1 (IRS-1), a major endogenous substrate for the insulin receptor which, when tyrosine is phosphorylated by the insulin receptor, interacts with and activates PI3-K. In ZR-75-1 cells, there were reduced levels of protein for IRS-1. In these cells, both Shc tyrosine phosphorylation and mitogen-activated protein kinase (MAP-K) activity were increased by the insulin receptor (indicating that the p21ras pathway may account for insulin-stimulated cell growth in ZR-75-1 cells). The PI3-K inhibitor LY294002 (50 microM) reduced insulin-stimulated growth in MCF-10A and MDA-MB157 cell lines, whereas it did not modify insulin effect on ZR-75-1 cell growth. The MAP-K/Erk (MEK) inhibitor PD98059 (50 microM) consistently reduced insulin-dependent growth in all three cell lines. Taken together, these data suggest that in breast cancer cells insulin may stimulate cell growth via PI3-K-dependent or-independent pathways.

Genetic diversity and its impact on disease severity in respiratory syncytial virus subtype-A and -B bronchiolitis before and after pandemic restrictions in Rome

OBJECTIVES

To scrutinize whether the high circulation of respiratory syncytial virus (RSV) observed in 2021-2022 and 2022-2023 was due to viral diversity, we characterized RSV-A and -B strains causing bronchiolitis in Rome, before and after the COVID-19 pandemic.

METHODS

RSV-positive samples, prospectively collected from infants hospitalized for bronchiolitis from 2017-2018 to 2022-2023, were sequenced in the G gene; phylogenetic results and amino acid substitutions were analyzed. Subtype-specific data were compared among seasons.

RESULTS

Predominance of RSV-A and -B alternated in the pre-pandemic seasons; RSV-A dominated in 2021-2022 whereas RSV-B was predominant in 2022-2023. RSV-A sequences were ON1 genotype but quite distant from the ancestor; two divergent clades included sequences from pre- and post-pandemic seasons. Nearly all RSV-B were BA10 genotype; a divergent clade included only strains from 2021-2022 to 2022-2023. RSV-A cases had lower need of O2 therapy and of intensive care during 2021-2022 with respect to all other seasons. RSV-B infected infants were more frequently admitted to intensive care units and needed O2 in 2022-2023.

CONCLUSIONS

The intense RSV peak in 2021-2022, driven by RSV-A phylogenetically related to pre-pandemic strains is attributable to the immune debt created by pandemic restrictions. The RSV-B genetic divergence observed in post-pandemic strains may have increased the RSV-B specific immune debt, being a possible contributor to bronchiolitis severity in 2022-2023.

Overexpression of membrane glycoprotein PC-1 in MDA-MB231 breast cancer cells is associated with inhibition of insulin receptor tyrosine kinase activity

MDA-MB231 human breast cancer cells are unresponsive to insulin and contain a glycoprotein inhibitor of insulin-stimulated insulin receptor (IR) tyrosine kinase activity. Prior studies in both fibroblasts from insulin- resistant non-insulin-dependent diabetes mellitus patients and transfected cells indicate that overexpression of membrane glycoprotein PC-1 reduces IR tyrosine kinase activity. In the present study, we measured PC-1 content and activity in MDA-MB231 and four other human breast cancer cell lines. We observed that PC-1 expression was 3- to 30-fold higher in MDA-MB231 cells when compared with the other breast cell lines. Wheat germ agglutinin extracts of MDA-MB231 cells inhibited IR tyrosine kinase activity. Treatment of these extracts with an antibody to PC-1 significantly reduced their ability to inhibit insulin-stimulated IR tyrosine kinase activity. In addition, when cell clones with different PC-1 activity were selected from MDA-MB231 cells, we found an inverse correlation (r = -0.741, P = 0.006) between the PC-1 activity and the insulin-stimulated IR autophosphorylation. A similar inverse correlation was observed in cell clones derived from the insulin-responsive breast cancer cell line MCF-7. By both immunoprecipitation and cross-linking studies we found PC-1 to be associated with IR. These studies indicate, therefore, that overexpression of PC-1 in MDA-MB231 cells may account, at least in part, for the reduced IR tyrosine kinase activity and suggest that PC-1 is a specific modulator of the IR activity in breast cancer cells.

The tall cell variant of papillary thyroid carcinoma: clinical and pathological features and outcomes

BACKGROUND

The tall cell variant (TCV) is a relatively rare variant of papillary thyroid cancer. Since a controversy exists whether or not the TCV has a worse outcome, the aim of our study was to retrospectively compare the clinicopathological features and outcomes in a group of TCV patients and a larger group of patients with classical papillary thyroid carcinoma (cPTC).

SUBJECTS AND METHODS

Data from 30 TCV and 293 cPTC patients were analyzed. Among the 293 cPTC, we also selected a "high-risk" cPTC group (no.=103) that was treated with the same protocol used for the TCV patients. All data were managed by Cox analysis.

RESULTS

Compared to all cPTC patients, TCV subjects displayed only a significantly higher rate of extrathyroid extension. At multivariate analysis, TCV was not an independent variable for the prediction of a high risk of persistent/recurrent disease. At the last follow-up observation, there was no difference in the disease status between the TCV and all cPTC patients. Moreover, "high-risk" cPTC patients had a significant increase in persistent/recurrent disease.

CONCLUSIONS

In our study, although the TCV histotype is associated with a higher prevalence of extrathyroid extension, it is characterized by an outcome that is not significantly different from that of all cPTC patients and is more favorable than that of "high-risk" cPTC patients. Only those TCV patients classified as "high risk" based on specific pathological and clinical features, according to current guidelines, should be treated aggressively, such as with a total thyroidectomy, neck lymph node dissection or ablative radioiodine treatment.

Interleukin-1 blocks insulin and insulin-like growth factor-stimulated growth in MCF-7 human breast cancer cells by inhibiting receptor tyrosine kinase activity

Interleukins-1 (IL-1s) are known to inhibit the growth of cultured breast cancer cells. We examined the effects of IL-1 alpha and IL-1 beta on insulin and insulin-like growth factor I (IGF-I) stimulation of cell growth and found that both IL-1s inhibited anchorage-dependent and independent growth of MCF-7 breast cancer cells. In cells incubated with IL-1 beta (100 U/ml), insulin receptor (IR) protein and messenger RNA were increased by 100%, while IGF-I receptor protein and transcript were not significantly changed. These data were confirmed by binding studies. Incubation of MCF-7 cells with IL-1s led, however, to a significant inhibition of IR and IGF-I receptor autophosphorylation (-55%) and phosphotransferase activity (-65%). Also, in 3T3/ HIR rat fibroblasts, transfected with and overexpressing IR, IL-1s decreased insulin-stimulated cell growth in soft agar and IR tyrosine kinase activity. The present findings suggest that IL-1s antagonize the insulin and IGF-I mitogenic effects in MCF-7 cells by blocking the receptor tyrosine kinase activity that is crucial for the mitogenic effect of these factors.

Assessment of indoor climate of Mogiła Abbey in Kraków (Poland) and the application of the analogues method to predict microclimate indoor conditions

The microclimatic monitoring of the historic church of Mogiła Abbey (Kraków, Poland) was carried out to study the impact of the environmental parameters on the organic and hygroscopic artworks. Specific indexes were proposed to objectively assess the quality of time series of temperature (T), relative humidity (RH), and carbon dioxide (CO₂) before applying the exploratory data analysis. The series were used to define the historic environmental conditions as stated in the European Standard EN 15757:2010 and with the use of the climate evaluation chart (CEC). It was found that the percentage of time in which T and RH values are within the allowable limits of the ASHRAE (2011) Class B is more than 85 %. This means that, for about 15 % of the time, there is a high risk of mechanical damage to highly vulnerable objects mainly due to the RH variability. The environment at the chancel resulted moister than that at the cornice, and the fungal growth is possible. In addition, the time-weighted preservation index (TWPI) is computed to evaluate the life expectancy of the objects, taking into account the environmental conditions of the site under study. The method of analogues, developed to predict the evolution of a system given observations of the past and without the knowledge of any equation among variables, was proposed and applied to the time series of temperature, relative humidity, and carbon dioxide with a 1-h sampling time to avoid the influence of the autocorrelation.

Expression of neurotrophins, GDNF, and their receptors in rat thyroid tissue

Levels of mRNA for neurotrophins (brain-derived neurotrophic factor, BDNF; neurotrophin 3, NT-3; neurotrophin 4, NT-4) and their receptors (trkA, trkB, trkC) and for glial cell line-derived neurotrophic factor (GDNF) and its receptors (ret, GDNFR-alpha) were measured in rat thyroid tissue by ribonuclease protection assays. In thyroid tissue the NT-3 mRNA level was threefold lower and the NT-4 mRNA level sixfold higher than those detected in adult rat hippocampus, while BDNF mRNA was undetectable. Very low levels of mRNA for truncated trkB and trkC receptors and no catalytic trkA, trkB or trkC were found. In conclusion NT-3 and NT-4, but not the corresponding functional receptors, are expressed in the thyroid tissue. Therefore, it is unlikely that these factors serve a direct local autocrine or paracrine function in thyroid cell types, and a target-derived mode of action on neurons innervating the thyroid tissue is suggested. An opposite result has been found for the neurotrophic factor GDNF: thyroid tissue showed a high level of transcripts for the GDNF receptor subunits (GDNFR-alpha and Ret), while GDNF mRNA was undetectable. The in situ hybridization analysis of GDNFR-alpha and ret mRNA revealed an interesting difference in the cell distribution of these transcripts: ret mRNA is selectively expressed in a subpopulation of cells scattered in the follicular epithelium and in the interfollicular spaces, while GDNFR-alpha expression is more homogeneous and widespread, including the more abundant cell type of the thyroid gland: the follicular cell. Double-labeling in situ hybridization/immunocytochemistry experiments, with a specific marker (calcitonin), showed that parafollicular cells express ret but not GDNFR-alpha. This differential distribution of the GDNF receptor components (GDNFR-alpha and ret) may reflect a peculiar biological role in intercellular communication in the thyroid gland.

Abnormal 1-hour post-load glycemia during pregnancy impairs post-partum metabolic status: a single-center experience

PURPOSE

Recent evidence indicates that people with normal glucose tolerance (NGT) but 1-h post-load plasma glucose (1-h OGTT) ≥ 155 mg/dl have an increased risk for developing Type 2 diabetes mellitus (T2DM), determining a new risk category with deeper metabolic impairment. The aim of this study was to identify, among women with gestational diabetes (GDM), which alterations at OGTT during pregnancy are more frequently associated with 1-h OGTT ≥ 155 mg/dl at post-partum examination.

METHODS

Among 297 women affected by GDM, we retrospectively evaluated 244 resulted NGT after delivery. Based on post-partum glucose levels at 1-h OGTT, these people were divided into 188 cases (77.0%) with 1-h OGTT < 155 mg/dl (L-NGT) and 56 (23.0%) with 1-h OGTT ≥ 155 mg/dl (H-NGT).

RESULTS

Abnormal glucose levels at 1-h OGTT during pregnancy (≥ 180 mg/dl) were more frequent in H-NGT than in L-NGT (39.3 vs. 24.6%, odds ratio 3.7 [95% CI 1.4-9.6]; p = 0.016). Moreover, H-NGT showed more frequently the simultaneous alteration of all three OGTT plasma glucose values during pregnancy (10.7 vs. 2.1%, odds ratio 4.5 [95% CI 1.5-20.3]; p = 0.038) and less frequently the alteration of fasting plasma glucose alone (14.3 vs. 30.8%, odds ratio 0.4 [95% CI 0.1-0.7]; p = 0.028).

CONCLUSIONS

Abnormal 1-h OGTT during pregnancy predicts an increased risk for post-partum 1-h OGTT ≥ 155 mg/dl in women with previous GDM. Even if NGT after delivery, these women may require a closer long-term post-partum follow-up, being at higher risk to develop future glucose intolerance.

Insulin-stimulated cell growth in insulin receptor substrate-1-deficient ZR-75-1 cells is mediated by a phosphatidylinositol-3-kinase-independent pathway

In many human breast cancers and cultured cell lines, insulin receptor expression is elevated, and insulin, via its own insulin receptor, can stimulate cell growth. It has recently been demonstrated that the enzyme phosphatidylinositol-3-kinase (PI3-K) mediates various aspects of insulin receptor signaling including cell growth. In order to understand the mechanisms for insulin-stimulated cell growth in human breast cancer, we measured insulin-stimulable PI3-K activity in a non-transformed breast epithelial cell line, MCF-10A, and in two malignantly transformed cell lines, ZR-75-1 and MDA-MB157. All three cell lines express comparable amounts of insulin receptors whose tyrosine autophosphorylation is increased by insulin, and in these cell lines insulin stimulates growth. In MDA-MB157 and MCF-10A cells, insulin stimulated PI3-K activity three- to fourfold. In ZR-75-1 cells, however, insulin did not stimulate PI3-K activity. In ZR-75-1 cells PI3-K protein was present, and its activity was stimulated by epidermal growth factor, suggesting that there might be a defect in insulin receptor signaling upstream of PI3-K and downstream of the insulin receptor. Next, we studied insulin receptor substrate-1 (IRS-1), a major endogenous substrate for the insulin receptor which, when tyrosine is phosphorylated by the insulin receptor, interacts with and activates PI3-K. In ZR-75-1 cells, there were reduced levels of protein for IRS-1. In these cells, both Shc tyrosine phosphorylation and mitogen-activated protein kinase (MAP-K) activity were increased by the insulin receptor (indicating that the p21ras pathway may account for insulin-stimulated cell growth in ZR-75-1 cells). The PI3-K inhibitor LY294002 (50 microM) reduced insulin-stimulated growth in MCF-10A and MDA-MB157 cell lines, whereas it did not modify insulin effect on ZR-75-1 cell growth. The MAP-K/Erk (MEK) inhibitor PD98059 (50 microM) consistently reduced insulin-dependent growth in all three cell lines. Taken together, these data suggest that in breast cancer cells insulin may stimulate cell growth via PI3-K-dependent or-independent pathways.

[Metachronous tumors of the breast. Mammographic findings]

In breast carcinoma patients the risk to develop a second lesion in the contralateral breast is two to six times higher than in control subjects. The second lesion is called metachronous and classified among bilateral breast cancers. This kind of lesion affects the patients who were mastectomized for breast carcinoma; it may be a primary lesion, when the histologic type is different from that of the first breast cancer or secondary, when the histologic type is the same as that of the first tumor and the second lesion is therefore a metastasis. This study was made to assess the incidence of metachronous lesions and the average time between the first and the second tumor and to investigate the value of mammographic followup. We selected 375 patients who had undergone mastectomy for different histologic types of breast carcinoma and examined the contralateral breast with mammography 6 months after surgery and then every 12 months, January 1990 through January 1992. Mammography showed metachronous lesions in 23 cases: 15 infiltrating ductal carcinomas, 6 infiltrating lobular carcinomas and 2 in situ carcinomas, the latter with histologic confirmation in the patients operated on for benign breast lesions. The incidence of metachronous tumors was 6%, including both the primary and the metastatic lesions; the average time between the first and the second tumors was 20 months. Mammography allowed metachronous lesions to be diagnosed in a very early stage, much earlier than in other studies not including mammography. Prognosis is definitely improved by the early diagnosis of primary breast cancer, when no metastatic spread is present, and also in case of primary metachronous lesions, which are very uncommon.

Surveillance of patients with differentiated thyroid cancer and indeterminate response: a longitudinal study on basal thyroglobulin trend

PURPOSE

This is a longitudinal study of retrospective data aimed at verifying whether repeated measurements of serum non-stimulated thyroglobulin (Tg) allow the prediction of persistent disease in patients with differentiated thyroid cancer (DTC) and indeterminate response.

METHODS

We examined 145 DTC patients with indeterminate response to therapy followed up for a median time of 68 months. Tg measurements and neck ultrasound (US) were performed every 6-12 months. The changes over time of repeated measurements of basal Tg were analyzed through the multilevel linear regression.

RESULTS

Seventy (48.3%) out of 145 patients spontaneously achieved an excellent response, while persistent indeterminate response was observed in 62 (42.7%) patients. The remaining 13 (9.0%) patients had progression: 3/13 with biochemical disease and 10/13 with structural disease. Tg steadily increased in patients with progressive disease (mean percentage change + 27.1% at each follow-up visit), while Tg decreased in patients without any evidence of progression (mean percentage change - 8.8%). This different trend between the two groups was not related to either different values of median TSH at baseline (0.32 vs 0.28 mIU/l, respectively) or to different trend of TSH during follow-up (p = 0.76). Basal Tg values did not increase in three out of ten patients with structural disease that was identified by neck US.

CONCLUSIONS

The importance of the study is that, in DTC patients with indeterminate response, rising values of unstimulated Tg, independently from the basal levels, may be useful to identify patients with progressive disease. These results are also useful to avoid unnecessary TSH stimulation.

Rebound effect of hypothalamic-pituitary thyreotropic activity: a new model to better understand hypothyroidism

PURPOSE

Hypothalamic-pituitary thyrotropic activity (HPta) is crucial since TSH is the mainstay for evaluating primary hypothyroidism (hT) and replacement therapy in clinical practice. Despite TSH values, some patients experience symptoms and metabolic alterations, raising several issues about hT. The aim of the study was to investigate factors influencing the TSH values achieved after a period of hT induced in a standardized and controlled manner (TSH_time1).

METHODS

Our institutional database was searched to extract records of differentiated thyroid cancer (DTC) patients undergoing a LT4 withdrawal protocol prior to radioiodine (RAI) administration. We collected clinical and biochemical parameters before LT4 discontinuation and after one month of induced hT. We performed Mann-Whitney U-test and linear regression analyses.

RESULTS

We included 102 patients, with a median age of 44 years. In univariate analyses, TSH_time1 was correlated with age (p 0.005) and the dose pro Kg/die of LT4 assumed until the discontinuation of LT4 (LT4_dose) (p 0.023). The higher the age, the lower the TSH_time1 level. The higher the LT4_dose, the higher the TSH_time1 level. After multivariate analysis, the fittest model included age, BMI, LT4_dose, and systemic inflammation response index with an adjusted R2 of 0.4.

CONCLUSION

The study highlights new mechanisms that influence HPta. HPta progressively reduces with age, and this must be considered when evaluating TSH values in the elderly. Furthermore, we report for the first time a rebound effect of HPta, determined by the dose pro Kg/die of LT4 taken prior to its discontinuation. Inflammation and metabolic status also affect these phenomena.

A dataset of criteria on the use of thermal insulation solutions in building facades located in Norway, Portugal and Italy

The building sector is responsible for a significant percentage of the energy consumption in Europe. The level of thermal insulation of the building envelope leads to decrease energy consumption, thus contributing towards a sustainable and efficient built environment. As a result, the choice of the most suitable thermal insulation solution to be applied both in new construction and in retrofitting of building facades is fundamental for a satisfactory thermal performance of the building. Nevertheless, the thermal insulation solution should not be chosen considering only the thermal performance, but rather based on a set of performance parameters (i.e., water resistance, fire performance, impact on the environment and human health, among others) and climate-related requirements. This data article includes a dataset on criteria adopted in three European countries (namely Norway, Portugal, and Italy) considering a PESTE analysis (i.e., criteria related to Political, Economic, Social, Technological, and Environmental questions). The main objective was to evaluate the knowledge and perception of people living and/or working in these countries about the use and the performance of thermal insulation solutions in building facades. To this aim a questionnaire was developed within the scope of the EEA Granted EFFICACY research project (November 2022 - February 2023), whose overall objective is to create a database that serves as a reference for the choice of thermal insulation solutions to be applied in building facades for thermal and energy performances optimization. This database contributes to systemize criteria and can be extended by other researchers or professionals in the area, as well as in other countries.

Temporal trends in the clinical presentation of Graves' orbitopathy: a single-center retrospective study

PURPOSE

Graves' ophthalmopathy (GO) is an autoimmune disease that affects orbital soft tissues and represents the most common extrathyroidal manifestation of Graves' disease (GD). The European Group of Graves' Ophthalmopathy (EUGOGO) has attempted to shed light on the European epidemiological picture of GO, suggesting that GO in newly diagnosed patients in recent years has a trend towards a less severe clinical presentation. There are no studies that focus this issue on the population of our area; we aimed to evaluate the trend of GO clinical presentation in our outpatient clinic through an observation period of 10 years.

METHODS

We compared 55 consecutive patients, 11 males (F) and 44 females (M), who came to our observation from January 2005 to December 2006 [Group 1 (G1)], with 56 patients, 15 males, and 41 females, who were referred to us from 2015 to 2016 [Group 2 (G2)]. We studied the following putative predictors of GO presentation and severity: thyroid function, smoking, diabetes, hypercholesterolemia, time from GO diagnosis to referral to our thyroid centre (TGOD), sex and age.

RESULTS

GO severity was significantly reduced in G2 vs. G1 (p = 0.04). TGOD ≥ 3 months was related to clinical characteristics of GO (severity and Clinical Activity Score ≥ 4) and was an independent predictor of GO severity (p = 0.01). The other variables evaluated had no independent effects.

CONCLUSIONS

We found that GO severity at presentation was significantly reduced over a ten-year observation period (2005-2006 vs. 2015-2016) in GO patients referred to our tertiary thyroid centre. TGOD ≥ 3 months was an independent predictor of GO severity.

Insulin and insulin-like growth factor-I (IGF-I) receptor overexpression in breast cancers leads to insulin/IGF-I hybrid receptor overexpression: evidence for a second mechanism of IGF-I signaling

The insulin receptor (IR) form hybrids with the closely related insulin-like growth factor-I (IGF-I) receptor (IGF-I-R). Because most human breast carcinomas overexpress both the IR and the IGF-I-R, we evaluated whether the insulin/IGF-I hybrid receptor (Hybrid-R) is also overexpressed in these tumors and what role it plays in breast cancer biology. Using specific ELISAs and Western blots, we measured Hybrid-R content and function in 8 human cultured breast cancer cell lines and 39 human breast cancer specimens. Hybrid-R content and function were also compared to the content and function of the IR and the IGF-I-R. Hybrid-R content exceeded the IGF-I-R content in >75% of breast cancer specimens and was directly related to the molar ratio of both the IR and IGF-I-R content, suggesting that Hybrid-R formation occurred by random assembly of IR and IGF-I-R half-receptors. Hybrid-Rs became tyrosine autophosphorylated when breast cancer cells were exposed to IGF-I but not when they were exposed to insulin. In cells with an elevated Hybrid-R content, Hybrid-R autophosphorylation in response to IGF-I exceeded IGF-I-R autophosphorylation, suggesting that most of the IGF-I effect occurred via the Hybrid-R. Furthermore, Hybrid-Rs mediated growth in response to IGF-I, as indicated by experiments with blocking antibodies to the IGF-I-R. These data indicated therefore that: (a) Hybrid-Rs are present and play a major role in mediating the IGF-I signal in breast cancer; (b) their expression is directly related to IR overexpression; and (c) potential therapies designed to block IGF-I actions in breast cancer must take into account the role of these Hybrid-Rs.