No molecule is an island, entire of itself; each molecule is a piece of the continent, a part of the main. If a cell be washed away by the sea, the body is less. Any cell's defect diminishes the whole, because it is involved in the whole.
Life requires the effective interactions of tens of thousands of different molecules for reproduction, growth, movement, and adhesion. Adhesion occurs between cells of the organism, between cells and extracellular molecules within the organism, and between the organism and the external environment. Adhesion can be permanent, or relatively permanent, and at times must be a more transient phenomenon. The passage of epidermal cells through the epidermis during differentiation illustrates the importance of the control of adhesion in normally functioning skin. Blistering and hyperkeratotic diseases are examples of the importance of adhesion in dermatologic diseases. Adhesion of cells to the extra-cellular molecules in the dermis
Goldsmith LA. Apologies to John Donne. Arch Dermatol. 1987;123(4):535-536. doi:10.1001/archderm.1987.01660280139041