Late Changes in the Extracellular Matrix of the Bladder after Radiation Therapy for Pelvic Tumors
Olga Streltsova,
Elena Kiseleva,
Varvara Dudenkova,
Ekaterina Sergeeva,
Ekaterina Tararova,
Marina Kochueva,
Svetlana Kotova,
Victoriya Timofeeva,
Katerina Yunusova,
Anna Bavrina,
Peter Timashev,
Anna Solovieva,
Anna Maslennikova
Affiliations
Olga Streltsova
E.V. Shakhov Department of Urology, Privolzhsky Research Medical University, 10/1 Minin and Pozharsky Sq., 603950 Nizhny Novgorod, Russia
Elena Kiseleva
Institute of Experimental Oncology and Biomedical Technologies, Privolzhsky Research Medical University, 10/1 Minin and Pozharsky Sq., 603950 Nizhny Novgorod, Russia
Varvara Dudenkova
Institute of Experimental Oncology and Biomedical Technologies, Privolzhsky Research Medical University, 10/1 Minin and Pozharsky Sq., 603950 Nizhny Novgorod, Russia
Ekaterina Sergeeva
Institute of Applied Physics of the RAS, 46 Ulyanova St., 603950 Nizhny Novgorod, Russia
Institute of Experimental Oncology and Biomedical Technologies, Privolzhsky Research Medical University, 10/1 Minin and Pozharsky Sq., 603950 Nizhny Novgorod, Russia
Svetlana Kotova
Department of Polymers and Composites, N.N. Semenov Federal Research Center for Chemical Physics, 4 Kosygin St., 119991 Moscow, Russia
Victoriya Timofeeva
Department of Polymers and Composites, N.N. Semenov Federal Research Center for Chemical Physics, 4 Kosygin St., 119991 Moscow, Russia
Katerina Yunusova
The Department of Anatomical Pathology, Privolzhsky Research Medical University, 10/1 Minin and Pozharsky Sq., 603950 Nizhny Novgorod, Russia
Anna Bavrina
Department of Medical Physics and Informatics, Privolzhsky Research Medical University, 10/1 Minin and Pozharsky Sq., 603950 Nizhny Novgorod, Russia
Peter Timashev
Department of Polymers and Composites, N.N. Semenov Federal Research Center for Chemical Physics, 4 Kosygin St., 119991 Moscow, Russia
Anna Solovieva
Department of Polymers and Composites, N.N. Semenov Federal Research Center for Chemical Physics, 4 Kosygin St., 119991 Moscow, Russia
Anna Maslennikova
Department of Oncology, Radiation Therapy and Radiological Diagnostics, Privolzhsky Research Medical University, 10/1 Minin and Pozharsky Sq., 603950 Nizhny Novgorod, Russia
Radiation therapy is one of the cardinal approaches in the treatment of malignant tumors of the pelvis. It leads to the development of radiation-induced complications in the normal tissues. Thus, the evaluation of radiation-induced changes in the extracellular matrix of the normal tissue is deemed urgent, since connective tissue stroma degradation plays a crucial role in the development of Grade 3–4 adverse effects (hemorrhage, necrosis, and fistula). Such adverse effects not only drastically reduce the patients’ quality of life but can also become life-threatening. The aim of this study is to quantitatively analyze the bladder collagen state in patients who underwent radiation therapy for cervical and endometrial cancer and in patients with chronic bacterial cystitis and compare them to the normal bladder extracellular matrix. Materials and methods: One hundred and five patients with Grade 2–4 of radiation cystitis, 67 patients with bacterial chronic cystitis, and 20 volunteers without bladder pathology were enrolled. Collagen changes were evaluated depending on its hierarchical level: fibrils and fibers level by atomic force microscopy; fibers and bundles level by two-photon microscopy in the second harmonic generation (SHG) mode; general collagen architectonics by cross-polarization optical coherence tomography (CP OCT). Results: The main sign of the radiation-induced damage of collagen fibrils and fibers was the loss of the ordered “basket-weave” packing and a significant increase in the total area of ruptures deeper than 1 µm compared to the intact sample. The numerical analysis of SHG images detected that a decrease in the SHG signal intensity of collagen is correlated with the increase in the grade of radiation cystitis. The OCT signal brightness in cross-polarization images demonstrated a gradual decrease compared to the intact bladder depending on the grade of the adverse event. Conclusions: The observed correspondence between the extracellular matrix changes at the microscopic level and at the level of the general organ architectonics allows for the consideration of CP OCT as a method of “optical biopsy” in the grading of radiation-induced collagen damage.
