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Introduction to Cancer, Conventional Therapies, and Bionano-Based Advanced Anticancer Strategies
Published in D. Sakthi Kumar, Aswathy Ravindran Girija, Bionanotechnology in Cancer, 2023
Under normal conditions, growth factors are the signals received by cells from their surroundings to determine their fate. Although an alteration in homeostasis and the initiation of the tumor are instigated by mutations rather than by the involvement of growth factors, the latter significantly regulates all subsequent phases of tumor progression, such as clonal expansion, invasion, angiogenesis, and colonization [100]. The essential role of growth hormones for clonal expansion allows for the fixation of oncogenic mutations and the increase in the number of initiated cells that are susceptive to additional mutations. Several tumor cells acquire the capacity to synthesize growth factors to which these cells are responsive [101]. In addition, various mechanisms may result in a consecutive activation pathway in cancer. At the receptor level, this overexpression may lead tumor cells to become hyper-responsive to growth hormones [102]. Tumor progression takes place merely when the basement membrane secretory ducts are dissolved. Growth factors play an essential role in the disruption of the basement membrane, as well as the penetration by tumor cells [103].
Ageing
Published in Henry J. Woodford, Essential Geriatrics, 2022
Renal mass peaks in the fourth decade of life and then progressively declines. Most of the loss is from the cortex, not the medulla. Ageing is associated with a progressive decline in renal function, although the degree of this varies between individuals. The basement membrane becomes thickened. There is focal glomerulosclerosis scattered across the cortex, which eventually results in nephron loss. Renal blood flow declines by around 10% per decade from the fourth decade onwards (from around 600 ml/min down to 300 ml/min). Renal arterial resistance progressively increases. Similarly, the glomerular filtration rate (GFR) declines by around 10% per decade from the fourth decade onwards. This is mainly due to nephron loss and reduced blood flow.49 It is estimated that 40–50% of people aged over 75 have a GFR below 60 ml/min/1.73m2 (i.e. classified as ‘chronic kidney disease stage 3') despite many not having a diagnosable renal disease.50 This has unclear significance. There is only a negligible difference in life expectancy for estimated GFR 45–59 compared to 60 or above for people aged over 75. The risk of progressing to end-stage renal disease is extremely low in this group. Such classifications may be contributing to the medicalisation of old age (see also osteoporosis page 330) without any clear benefit.
Comparative Anatomy, Physiology, and Biochemistry of Mammalian Skin
Published in David W. Hobson, Dermal and Ocular Toxicology, 2020
The epidermal-dermal junction is characterized by the presence of the basement membrane. Several functions have been attributed to the basement membrane. One is that it can act as a selective barrier between the epidermis and dermis, restricting some molecules and permitting the passage of others. It also provides support for the epidermis.
COL28 promotes proliferation, migration, and EMT of renal tubular epithelial cells
Published in Renal Failure, 2023
Linlin Li, Hong Ye, Qiaoling Chen, Lixin Wei
EMT is an important pathologic pathway involved in renal interstitial fibrosis [35]. The first and most critical step in EMT is reducing E-cadherin expression. Once E-cadherin is reduced, cell-to-cell adhesion decreases, the cells lose their tight intercellular junctions, and finally lose epithelial cell polarity; after EMT, the cells also show increased α-SMA expression, suggesting that the cells acquired a myofibroblast-like phenotype, enhancing their proliferation and invasive potentials [35,36]. At last, basement membrane degradation is also a feature of kidney EMT [37]. ZO-1 is one of the important proteins belonging to tight junctions (TJs) [38,39]. ZO-1 is important to maintain the polarity of epithelial cells and is also involved in forming the cytoskeleton, cell proliferation, and differentiation [40,41]. During EMT, the decrease of ZO-1 is accompanied by a decrease of Claudin, occludin expression, and the cleavage of E-cadherin on the plasma membrane [42–44]. COL28 overexpression could inhibit the expression of ZO-1 and E-cadherin in HK-2 cells, and promote the expression of α-SMA, suggesting that COL28 can affect the integrity of tight junctions of epithelial cells, destroy the adhesion between cells, inhibit the formation of renal tubular epithelial cells polarity, and promote EMT [43], thus aggravating kidney injury.
Spatial composition and turnover of the main molecules in the adult glomerular basement membrane
Published in Tissue Barriers, 2023
David W. Smith, Azin Azadi, Chang-Joon Lee, Bruce S. Gardiner
The fiber network across the GBM appears to be non-uniformly distributed, as can be identified by transmission electron microscopy (TEM) (for example, Figure 2 in [25] or Figure 8a in [26]). Traversing the GBM from the endothelial side to the epithelial side, three distinct regions are usually identified: (i) the lamina rara interna (LRI), (ii) the lamina densa (LD), and (iii) the lamina rara externa (LRE).25 Note that there are several naming conventions for basement membrane that have arisen. We intend to use LRI, LD, and LRE here when referring to the GBM, as this provides a convenient reference to locations within the GBM. Further, lamina densa is sometimes used synonymously with basement membrane (e.g. Mouse Genome Informatics, Gene Ontology Browser27) or a name given based on optical appearance, rather than location.
Enhanced antitumour efficacy of functionalized doxorubicin plus schisandrin B co-delivery liposomes via inhibiting epithelial-mesenchymal transition
Published in Journal of Liposome Research, 2021
Fu-Yi Cai, Xue-Min Yao, Ming Jing, Liang Kong, Jing-Jing Liu, Min Fu, Xin-Ze Liu, Lu Zhang, Si-Yu He, Xue-Tao Li, Rui-Jun Ju
The basement membrane is the barrier in the process of invasion and metastasis of human tumours. If tumours want to metastasize to other parts, it not only need to reduce the adhesion between cells, but also have the ability to dissolve and break away from the basement membrane, so that it can enter the blood or lymphatic circulation to play the role of metastasis. Therefore, in order to measure the anti-metastasis ability of various formulations, it is necessary to carry out the invasive test of cancer cells. Using matrigel to simulate the structure of basement membrane, only a few of the A549 cells treated by PFV modified DOX plus schisandrin B liposomes reached the basement room through the matrigel. The inhibitory effects of schisandrin B liposomes was stronger than that of DOX liposomes and PFV modified DOX liposomes, which were not ideal (Figure 5(A,C)). Tumour tissue decomposes the basement membrane by secreting proteolytic enzymes such as matrix metalloproteinase (MMP) and aspartic proteinase (caspase), so the expression of intracellular proteolytic enzymes can also reflect the invasive ability of tumour cells. The expression of MMP-9 in cells was determined by ELISA kit. It was found that the results were the same as those aforementioned (Figure 8(B)). The nano-targeting liposomes we prepared has a certain inhibitory effect compared with other groups.