VEGF-C inhibition reverses resistance of bladder cancer cells to cisplatin via upregulating maspin

Mini-Review: Current Bladder Cancer Treatment-The Need for Improvement

Bladder cancer is the tenth most common cancer and is a significant burden on health care services worldwide, as it is one of the most costly cancers to treat per patient. This expense is due to the extensive treatment and follow-ups that occur with costly and invasive procedures. Improvement in both treatment options and the quality of life these interventions offer has not progressed at the rates of other cancers, and new alternatives are desperately needed to ease the burden. A more modern approach needs to be taken, with urinary biomarkers being a positive step in making treatments more patient-friendly, but there is still a long way to go to make these widely available and of a comparable standard to the current treatment options. New targets to hit the major signalling pathways that are upregulated in bladder cancer, such as the PI3K/AkT/mTOR pathway, are urgently needed, with only one drug approved so far, Erdafitinib. Immune checkpoint inhibitors also hold promise, with both PD-1 and CDLA-4 antibody therapies approved for use. They effectively block ligand/receptor binding to block the immune checkpoint used by tumour cells. Other avenues must be explored, including drug repurposing and novel biomarkers, which have revolutionised this area in other cancers.

Mitigative potential of rhoifolin against cisplatin prompted testicular toxicity: biochemical, spermatogenic and histological based analysis

Rhoifolin (ROF) is a naturally occurring flavonoid compound with diverse pharmacological and therapeutic benefits. The current investigation was designed to evaluate the curative potential of Rhoifolin (ROF) against Cisplatin (CP) induced testicular damage. Mature male albino rats (n = 48) were randomly distributed into 4 equal groups: control, CP (10 mg/kg), CP + ROF (10 mg/kg + 20 mg/kg) and ROF (20 mg/kg) supplemented group. Following 56 days of the trial, biochemical, inflammatory markers, spermatogenic, steroidogenic, hormonal, apoptotic, anti-apoptotic, and histopathological parameters were evaluated. The exposure to CP markedly (p < 0.05) lowered the activities of anti-oxidant enzymes, glutathione reductase (GSR), catalase (CAT), and glutathione peroxidase (GPx) as well as superoxide dismutase (SOD) in testicular tissues of male albino rats. Besides the levels of reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS) were considerably augmented in CP exposed rats. The administration of CP also increased the level of inflammatory cytokines i.e. IL-6, TNF-α, 1L-1β and NF-κβ as well as COX-2 activity. Additionally, a notable (p < 0.05) upsurge was observed in dead sperms count, abnormality in the tail, midpiece as well as head of sperms along with a notable decline in sperm motility in CP treated rats. Moreover, the expressions of steroidogenic enzymes were also lowered in CP administered group. The levels of follicle stimulating hormone (FSH) and plasma testosterone as well as luteinizing hormone (LH) were decreased in CP treated group. Moreover, the expression of Bax as well as Caspase-3 (apoptotic markers) were increased. On the other hand, Bcl-2 expression (anti-apoptotic marker) was reduced. Furthermore, the histopathological analysis showed that CP considerably (p < 0.05) damaged the testicular tissues. However, the administration of ROF significantly reduced the damaging effects of CP in testicular tissues. The results of our study suggested that ROF can potentially alleviate CP-induced testicular damages due to its androgenic, anti-oxidant and anti-inflammatory as well as anti-apoptotic nature.

Inhibition of VEGF binding to neuropilin-2 enhances chemosensitivity and inhibits metastasis in triple-negative breast cancer

Although blocking the binding of vascular endothelial growth factor (VEGF) to neuropilin-2 (NRP2) on tumor cells is a potential strategy to treat aggressive carcinomas, a lack of effective reagents that can be used clinically has hampered this potential therapy. Here, we describe the generation of a fully humanized, high-affinity monoclonal antibody (aNRP2-10) that specifically inhibits the binding of VEGF to NRP2, conferring antitumor activity without causing toxicity. Using triple-negative breast cancer as a model, we demonstrated that aNRP2-10 could be used to isolate cancer stem cells (CSCs) from heterogeneous tumor populations and inhibit CSC function and epithelial-to-mesenchymal transition. aNRP2-10 sensitized cell lines, organoids, and xenografts to chemotherapy and inhibited metastasis by promoting the differentiation of CSCs to a state that is more responsive to chemotherapy and less prone to metastasis. These data provide justification for the initiation of clinical trials designed to improve the response of patients with aggressive tumors to chemotherapy using this monoclonal antibody.

Emerging Biomarkers for Predicting Bladder Cancer Lymph Node Metastasis

Bladder cancer is one of the leading causes of cancer deaths worldwide. Early detection of lymph node metastasis of bladder cancer is essential to improve patients' prognosis and overall survival. Current diagnostic methods are limited, so there is an urgent need for new specific biomarkers. Non-coding RNA and m6A have recently been reported to be abnormally expressed in bladder cancer related to lymph node metastasis. In this review, we tried to summarize the latest knowledge about biomarkers, which predict lymph node metastasis in bladder cancer and their mechanisms. In particular, we paid attention to the impact of non-coding RNA on lymphatic metastasis of bladder cancer and its specific molecular mechanisms, as well as some prediction models based on imaging, pathology, and biomolecules, in an effort to find more accurate diagnostic methods for future clinical application.

lncRNA and Mechanisms of Drug Resistance in Cancers of the Genitourinary System

Available systemic treatment options for cancers of the genitourinary system have experienced great progress in the last decade. However, a large proportion of patients eventually develop resistance to treatment, resulting in disease progression and shorter overall survival. Biomarkers indicating the increasing resistance to cancer therapies are yet to enter clinical routine. Long non-coding RNAs (lncRNA) are non-protein coding RNA transcripts longer than 200 nucleotides that exert multiple types of regulatory functions of all known cellular processes. Increasing evidence supports the role of lncRNAs in cancer development and progression. Additionally, their involvement in the development of drug resistance across various cancer entities, including genitourinary malignancies, are starting to be discovered. Consequently, lncRNAs have been suggested as factors in novel therapeutic strategies to overcome drug resistance in cancer. In this review, the existing evidences on lncRNAs and their involvement in mechanisms of drug resistance in cancers of the genitourinary system, including renal cell carcinoma, bladder cancer, prostate cancer, and testicular cancer, will be highlighted and discussed to facilitate and encourage further research in this field. We summarize a significant number of lncRNAs with proposed pathways in drug resistance and available reported studies.

Subcellular expression of maspin – from normal tissue to tumor cells

Maspin or SerpinB5, a member of the serine protease inhibitor family, was shown to function as a tumor suppressor, especially in carcinomas. It seems to inhibit invasion, tumor cells motility and angiogenesis, and promotes apoptosis. Maspin can also induce epigenetic changes such as cytosine methylation, de-acetylation, chromatin condensation, and histone modulation. In this review, a comprehensive synthesis of the literature was done to present maspin function from normal tissues to pathologic conditions. Data was sourced from MEDLINE and PubMed. Study eligibility criteria included: Published in English, between 1994 and 2019, specific to humans, and with full-text availability. Most of the 118 studies included in the present review focused on maspin immunostaining and mRNA levels. It was shown that maspin function is organ-related and depends on its subcellular localization. In malignant tumors, it might be downregulated or negative (e.g., carcinoma of prostate, stomach, and breast) or upregulated (e.g., colorectal and pancreatic tumors). Its subcellular localization (nuclear vs cytoplasm), which can be proved using immunohistochemical methods, was shown to influence both tumor behavior and response to chemotherapy. Although the number of maspin-related papers increased, the exact role of this protein remains unknown, and its interpretation should be done with extremely high caution.

Apocynin alleviates cisplatin-induced testicular cytotoxicity by regulating oxidative stress and apoptosis in rats

The aim of this study was to investigate possible protective effects of apocynin (APO), an NADPH oxidase (NOX2) inhibitor, on cisplatin (CIS)-induced testicular damage. Four groups of Sprague Dawley rats were used: control, APO, CIS and CIS+APO. Following a single intraperitoneal dose of CIS (7 mg/kg), either dimethyl sulfoxide or APO (25 mg/kg) was administered orally for 5 days. Testis samples were evaluated microscopically for general histopathology and ultrastructure, proliferating and apoptotic cells, and NOX2 localization. Sperm parameters were evaluated. Malondialdehyde (MDA) and glutathione (GSH) levels and superoxide dismutase (SOD), myeloperoxidase (MPO) and 8-hydroxy-2-deoxyguanosine (8-OHdG) activities were analysed biochemically. The CIS group had a greater number of abnormal spermatozoa, atrophic seminiferous tubules, apoptotic and NOX2-immunoreactive cells; numerous large vacuole formations in the cytoplasm of germinal epithelial cells; degenerated intercellular tight junctions; higher MDA, 8-OHdG and MPO levels; decreased numbers of spermatozoa; and lower proliferative index and GSH and SOD levels. All these histologic and biochemical results were better in the CIS+APO group. CIS causes testicular damage by decreasing spermatogenic cell lines and increasing NOX2 activity and apoptosis through oxidative stress. APO prevents testicular damage, possibly by its antioxidant effects.

Knockdown of HMGN5 increases the chemosensitivity of human urothelial bladder cancer cells to cisplatin by targeting PI3K/Akt signaling

High-mobility group nucleosome-binding domain 5 (HMGN5) is the latest member of the HMGN family of proteins. Numerous studies have confirmed the carcinogenic role of HMGN5 in cancer, but its function in the regulation of chemosensitivity is largely unknown and controversial. A previous study by the authors of the present study demonstrated that HMGN5 contributes to the progression of urothelial bladder cancer (UBC) through regulating the expression of E-cadherin and vascular endothelial growth factor (VEGF)-C, which are associated with the sensitivity of tumor cells to cisplatin. Therefore, the present study aimed to elucidate the mechanisms underlying the regulation of HMGN5 and investigate the involvement of HMGN5 in cisplatin treatment. The results of the present study revealed that HMGN5 is able to positively regulate the expression of phosphorylated (p-)Akt in UBC cells. In addition, HMGN5 expression was negatively associated with the response of UBC cells to cisplatin. The findings indicated that HMGN5 may be a potential therapeutic target of cisplatin treatment, since cisplatin treatment reduced HMGN5 expression in a dose-dependent manner. It was also confirmed that the knockdown of HMGN5 decreased the viability, colony formation and invasion of 5637 cells but increased apoptosis under cisplatin treatment. The changes caused by HMGN5 knockdown in 5637 cells were able to be reversed by treatment with insulin-like growth factor-1 (IGF-1), which is a phosphoinositide 3-kinase (PI3K)/Akt signaling activator. Additionally, with the decreased expression of HMGN5, the expression of p-Akt, slug, E-cadherin and VEGF-C was subsequently inhibited. By contrast, the expression of cytochrome c, cleaved-caspase-3 and cleaved-poly ADP ribose polymerase was increased following HMGN5 knockdown. Consistently, these changes in protein expression were able to be reversed by IGF-1 treatment. In conclusion, findings from the in vitro experiments indicate that HMGN5 may a target of cisplatin treatment and that the inhibition of HMGN5 increases the chemosensitivity of UBC cells by inhibiting PI3K/Akt signaling.