Current Topics in Experimental Endocrinology

Volume 3

L Martini, V. H. T. James

• Publisher: Academic Press
• Year: 2013
• Print ISBN: 9780121532031
• eBook ISBN: 9781483217352
• Topic: Medicine
• Subtopic: Diseases & Allergies

Current Topics in Experimental Endocrinology, Volume 3 covers the relationship between the endocrine system and some types of tumors. The book discusses the perspectives, pitfalls, and potentials of tissue culture in endocrine research; the tumor types associated with ectopic adrenocorticotropin hormone secretion, particularly nonendocrine tumors; and the hormonal control of breast cancer growth in women and rats. The text also describes the status of steroid receptors in breast tumors; the physiopathological aspects of prolactin secretion in patients with pituitary tumors; and the biochemical endocrinology of prostatic tumors. The ectopic production of human chorionic gonadotropin and its alpha- and beta-subunits is also considered. Endocrinologists, oncologists, chemists, gynecologists, and students taking related courses will find the book invaluable.

Tissue Culture in Endocrine Research: Perspectives, Pitfalls, and Potentials

Michael J. O’Hare, Morag L. Ellison and A. Munro Neville, Unit of Human Cancer Biology, Ludwig Institute for Cancer Research, In Conjunction With Royal Marsden Hospital, Sutton, Surrey, England

Publisher Summary

This chapter discusses tissue culture’s role in some selected chemical, pathological, and fundamental aspects of the endocrinology of both steroid and peptide hormone-secreting tissues. Tissue culture has many forms; none is easy and many are both time-consuming and laborious. In some respects, they still represent art forms with a complexity that defies simple analysis. The chapter describes some of the reasons why this has occurred. If, however, tissue culture is to achieve preeminence in experimental studies, its days as an art rather than a science must be numbered. Certain basic problems of methodology, however, still remain to be solved by systematic experimentation, leading ultimately to the preservation of complete structural and functional integrity of purified endocrine cells in culture under completely defined conditions. Further progress in the use of tissue culture to study functional activity and growth may be considerably hampered until these requirements are fulfilled. It would be foolhardy to suppose, however, that there exists one all-encompassing ideal medium or system of culture, and conditions may have to be optimized for each individual cell type or tissue, particularly for human material. Failure to contend with these and similar problems may serve to further perpetuate the myth of culture being inevitably associated with radical changes in the behavior of cells and tissues. A further goal must also be dispensing with the use of serum to sustain cultured cells, as many of the complications that beset endocrine cultures in particular stem from its use. Although efforts in this direction are being made, much remains to be discovered about the precise role played by serum in cultures and the way by which it can be replaced by defined constituents.

I Introduction

II Options in Tissue Culture

A Culture Media

B Culture Systems

III Regulation of Functional Activity and Growth in Endocrine Cells in Culture

A Steroid-Secreting Cells in Culture

B Calcitonin-Secreting Cells in Culture

IV Secondary Applications of Endocrine Cultures

A Hormone Production

B Biological Assay Systems

V Discussion

References

I Introduction

During the last few years there has been a considerable increase in the use of tissue culture in endocrinology as in all fields of biomedical investigation, both as a means of exploring basic endocrine phenomena, and for studying endocrine aspects of cancer. This renewed interest has been largely due to the development of ultrasensitive analytical methods, exemplified by the radioimmunoassay, by which levels of hormones synthesized by individual cultures can now be readily measured. In addition, recent years have seen an increasing availability of a wide range of culture requisites such as defined media, sera, and culture vessels. These factors have greatly increased the practical feasibility of tissue culture, which now provides numerous models for investigating the functional activity of normal and neoplastic endocrine and paraendocrine tissues (Ellison and Neville, 1973).

In its ultimate form, a capability of tissue culture to sustain all tissue-specific functions and responses in vitro for an indefinite period of time under completely defined conditions would allow it to supersede a variety of other methods. At the present time, however, it is clear that there is still some way to go before this goal is achieved. Few, if any, of the tissue culture models of endocrine function currently in use provide a complete facsimile of endocrine cells and tissues in vivo. Nevertheless, the capability to dissect endocrine relationships in vitro affords a powerful tool for their analysis that cannot be ignored. Although problems remain in defining the precise conditions of culture appropriate to specific tissues and functions, it has proved possible by judicious selection of techniques to reproduce certain essential features of endocrine behavior for extended periods of time in vitro. Even when changes in functional activity occur as a result of culture, they can indirectly illuminate the factors that regulate hormone secretion in vivo. A notable example of this was the demonstration of the enhanced secretion of prolactin by cultured hypophyses freed from the inhibitory influence of the hypothalamus (Meites et al., 1961; Pasteels, 1961).

On the whole, however, the early years of endocrine tissue culture were not particularly encouraging. Following the pioneering experiments of Carrel and Burrows (1910), only intermittent attempts were made to culture endocrine glands until the advent of reliable methods of culture with the use of antibiotics to control microbial contamination. Even then its impact was not great because of the relative insen-sitivity of the then current methods of hormone analysis although human chorionic gonadotropin (HCG) secretion in vitro was demonstrated by Gey et al. in 1938. Many cultures, however, failed to produce measurable levels of hormones in spite of the fact that evidence of continued activity could sometimes be inferred from morphological changes seen in co-cultured responsive tissues (for review of early work, see Gaillard and Schaberg, 1965). Nonetheless, tissue culture made some outstanding, if isolated, contributions during this period. These included the identification of somatomedin (sulfation factor) using cultures of cartilage (Salmon and Daughaday, 1957) and later of hypothalamic-releasing factors using pituitary cultures (see Burgus et al., 1976).

At this time, however, the general failure to demonstrate specialized functions in cultures of adult cells led to the widely disseminated assumption that such cells “dedifferentiated” in culture. A belief therefore grew that tissue culture methods as a whole were implicitly unsuited to a study of endocrine functions, a view that is still held by some today (Schulster et al., 1976). The misapprehension that all adult cells inevitably “dedifferentiate” in culture has now been dispelled to a large extent by a body of definitive evidence to the contrary (for general reviews, see Green and Todaro, 1967; Wigley, 1975). It has now become clear that most of the unsuccessful early attempts failed for essentially technical reasons such as the overgrowth of cultures by adventitious cell types present in the original tissues, including fibroblast-like cells (Sato et al., 1960) and vascular endothelial cells or pericytes (Franks and Wilson, 1970).

Interest in tissue culture in endocrinology has now revived from the almost universal skepticism of a decade ago to the extent that numerous attempts are now being made to derive significant information from almost all conceivable hormone-producing cells and tissues. It is the purpose of this chapter to outline various modes of tissue culture currently available and applicable to endocrine tissues, illustrated by selected examples drawn from our own experience as well as that of other workers. Pitfalls and problems in the use of tissue culture in endocrinology undoubtedly exist, and by discussing and illustrating some of them we hope to place current progress in this field in a critical perspective. No attempt at a comprehensive review of endocrine cultures will be made, since this would be rapidly outdated at the current rate of progress. Furthermore, in some instances cultures of specific endocrine glands have been recently reviewed in this manner (for the anterior pituitary, see Tixier-Vidal, 1975).

The examples illustrated here will be drawn in the main from cases where tissue culture has afforded the most suitable, and in many cases the only method whereby certain ...

Table of contents

• Cover image
• Title page
• Table of Contents
• Contributors
• Editorial Board
• Copyright page
• List of Contributors
• Preface
• Chapter 1: Tissue Culture in Endocrine Research: Perspectives, Pitfalls, and Potentials
• Chapter 2: Adrenocorticotropin and Related Peptides in Nonendocrine Tumors
• Chapter 3: Hormonal Control of Breast Cancer Growth in Women and Rats*
• Chapter 4: Steroid Receptors in Breast Tumors—Current Status
• Chapter 5: Prolactin and Pituitary Tumors*
• Chapter 6: Biochemical Endocrinology of Prostatic Tumors
• Chapter 7: Ectopic Production of Human Chorionic Gonadotropin and Its α- and β-Subunits*
• Subject Index