The subcellular basis of damage to the human urinary bladder induced by irradiation

Abstract

The effects of x-irradiation on the subcellular structure of the human urinary bladder were investigated by electron microscopic examination of biopsies taken during check cystoscopies from 25 patients between 1 month and 22 years after completion of a course of therapeutic radiation. All tissues of the bladder wall were damaged to some extent by the treatment. In the urothelium this was reflected by the development of more than the usual numbers of lysosomes and autophagic vacuoles in all cell layers. In the bladder wall, large often binucleate or multinucleate fibroblasts were prominent and persistent in all specimens and were associated with the development of progressive fibrosis. The vasculature and the muscle coats of the bladder wall were also damaged. In the blood vessels many endothelial cells were oedematous or necrotic and some intravascular coagulation was also observed. Smooth muscle cells became oedematous soon after irradiation, and after longer time intervals there was focal death and loss of individual muscle cells. The observed degeneration and extensive necrosis of the bladder wall, which involved severe destruction and disorganization of the muscular layers, is sufficient to explain the clinical sequelae of bladder irradiation, namely loss of elasticity, reduced capacity and incomplete micturition with residual urine.

Bone Marrow-Derived Cells Implanted into Radiation-Injured Urinary Bladders Reconstruct Functional Bladder Tissues in Rats

“…26,27 The second phase is the infiltration of inflammatory cells. [26][27][28] The third phase is chronic and is associated with collagen deposition and developing fibrosis. 26,27,29 Some studies reported that animal urinary bladder damage induced by a single dose of radiation had pathological changes that included epithelial denudation and focal hyperplasia with ulceration, 26 changes in axon profiles and mast cell density, 27 and increased formation of superoxide free radicals.…”

Neosis: A Novel Type of Cell Division in Cancer

“…Consistent with this, MN/PGs and small cells with high N/C ratios have been reported in residual tumor tissues during recurrent growth of tumors. 71,72 Neosis as the Mechanism of Self-Renewal in Tumor Cells. The process of self renewal in cancer cells occurs through a low frequency of tumor initiating cells the precursors of which are thought to be constantly maintained as cancer stem cells in the tumor cell population.…”

Manganese superoxide dismutase gene therapy protects against irradiation-induced cystitis

“…Rats irradiated with 20 Gy all exhibited small and contracted bladders 6 mo after treatment (19,40). In human bladders, subepithelial fibrosis became more extensive with time after irradiation (1). The loss of bladder muscle and damage to vascular endothelial cells and bladder neurons was also evident (39).…”