Cure Alveolar Soft Part Sarcoma International (iCureASPS)

Sarcoma and thyroid disorders: a common etiology?


Abstract

We have recently observed that many of our sarcoma patients presented also with thyroid disorders. Literature data are almost unavailable on this topic. The relationship between the sarcoma and thyroid disorders is examined. Retrospective analysis of files of patients with sarcoma and clinically overt thyroid disorders was carried out. Of the 375 patients with soft tissue sarcomas (STS) and 235 with bone sarcoma (BS) including small blue round cell tumors (SBRC), 28 patients (4.6%) had an associated significant thyroid disorder. The types of sarcoma were mainly liposarcoma followed by malignant fibrous histiocytoma, leiomyosarcoma and bone sarcoma. The primary sites were mainly limb and trunk. The interval between the diagnosis of the thyroid disorder and the sarcoma varied between -14 years (thyroid first) and +16.5 years (thyroid later) with a median of -0.2 years. Thyroid disorders included goiter, thyroiditis and carcinoma. There are both basic-science and clinical evidence to a possible common pathway that leads to the association between overt thyroid disorders and sarcomas of bone or soft tissues. Oncogene erbA activity is related to thyroid receptors to T3 and to development of sarcoma. Cross talk of the sarcoma oncogene and the erbA might contribute to the development of sarcoma. The thyroid hormone receptor and the highly related viral oncoprotein v-erbA are found exclusively in the nucleus as stable constituents of chromatin. It has been shown that v-erbA can block the spontaneous differentiation in erythroid cells transformed by various retroviral oncogenes. V-erbA can alter the spectrum of neoplasia induced by the v-src oncogene, which causes predominantly sarcomas and erythroblastosis in chicks. The erbA can cooperate with other oncogenes such as v-erbB or with v-fms, v-ras, and c-kit. Cooperation with v-myc may play a role in the development of rhabdomyosarcoma especially in thyroid hormone deficiency state. The possible clinical implications are the need to screen patients with sarcoma to thyroid disorders, and patients with thyroid disorders for malignant diseases.



https://pubmed.ncbi.nlm.nih.gov/12066223/

The thyroid hormone receptor functions as a ligand-operated developmental switch between proliferation and differentiation of erythroid progenitors

Abstract

The avian erythroblastosis virus (AEV) oncoprotein v-ErbA represents a mutated, oncogenic thyroid hormone receptor alpha (c-ErbA/ TRalpha). v-ErbA cooperates with the stem cell factor-activated, endogenous receptor tyrosine kinase c-Kit to induce self-renewal and to arrest differentiation of primary avian erythroblasts, the AEV transformation target cells. In this cooperation, v-ErbA substitutes for endogenous steroid hormone receptor function required for sustained proliferation of non-transformed erythroid progenitors. In this paper, we propose a novel concept of how v-ErbA transforms erythroblasts. Using culture media strictly depleted from thyroid hormone (T3) and retinoids, the ligands for c-ErbA/TRalpha and its co-receptor RXR, we show that overexpressed, unliganded c-ErbA/ TRalpha closely resembles v-ErbA in its activity on primary erythroblasts. In cooperation with ligand-activated c-Kit, c-ErbA/ TRalpha causes steroid-independent, long-term proliferation and tightly blocks differentiation. Activation of c-ErbA/ TRalpha by physiological T3 levels causes the loss of self-renewal capacity and induces synchronous, terminal differentiation under otherwise identical conditions. This T3-induced switch in erythroid progenitor development is correlated with a decrease of c-ErbA-associated histone deacetylase activity. Our results suggest that the crucial role of the mutations activating v-erbA as an oncogene is to 'freeze' c-ErbA/ TRalpha in its non-liganded, repressive conformation and to facilitate its overexpression.

https://pubmed.ncbi.nlm.nih.gov/9687498/

Ligand Operated Channels

Last Updated on Sat, 19 Dec 2020
This is the most direct mechanism by which chemically regulated gates can be opened. In this case, the ion channel runs through the receptor itself. The ion channel is opened by the binding of the receptor to the neurotransmitter ligand.

Thyroid hormone and breast carcinoma
Primary hypothyroidism is associated with a reduced incidence of primary breast carcinoma

Abstract
BACKGROUND

To investigate the role of primary hypothyroidism (HYPT) on breast carcinogenesis, the authors evaluated 1) the association between HYPT and a diagnosis of invasive breast carcinoma and 2) the clinicopathologic characteristics of breast carcinoma in patients with HYPT.


CONCLUSIONS

Primary HYPT was associated with a reduced risk for PBC and a more indolent invasive disease. These data suggest a possible biologic role for thyroid hormone in the etiology of breast carcinoma and indicate areas of research for the prevention and treatment of breast carcinoma. Cancer 2005. © 2005 American Cancer Society.


https://acsjournals.onlinelibrary.wiley ... cncr.20881