Benzyl isothiocyanate promotes miR-99a expression through ERK/AP-1-dependent pathway in bladder cancer cells

Mechanistic insights of lenvatinib: enhancing cisplatin sensitivity, inducing apoptosis, and suppressing metastasis in bladder cancer cells through EGFR/ERK/P38/NF-κB signaling inactivation

BACKGROUND

The persistent activation of the epidermal growth factor receptor (EGFR) leads to the activation of downstream oncogenic kinases and transcription factors, resulting in tumor progression and an increased resistance to cisplatin in bladder cancer (BC) cells. Lenvatinib, an oral multikinase inhibitor, has the potential to offer therapeutic benefits as an adjuvant treatment for BC patients. The investigation into its application in bladder cancer treatment is a valuable endeavor. The primary goal of this study is to confirm the effectiveness and mechanism of lenvatinib in inhibiting the progression of BC and enhancing the anticancer efficacy of cisplatin.

MATERIALS

Three BC cell lines, namely, TSGH-8301, T24, and MB49, along with an MB49-bearing animal model, were utilized in this study.

RESULTS

In vitro experiments utilizing MTT assays demonstrated that lenvatinib sensitized BC cells to cisplatin, exhibiting a synergistic effect. Flow cytometry indicated apoptotic events and signaling, presenting that lenvatinib effectively induced apoptosis and triggered extrinsic/intrinsic apoptotic pathways. In vivo studies using a mouse model of BC confirmed the antitumor efficacy of lenvatinib, demonstrating significant tumor growth suppression without inducing toxicity in normal tissues. Western blotting analysis and immunohistochemistry stain revealed EGF-phosphorylated EGFR and EGFR-mediated ERK/P38/NF-κB signaling were suppressed by treatment with lenvatinib. In addition, lenvatinib also suppressed anti-apoptotic (MCL1, c-FLIP, and XIAP) and metastasis-related factors (Twist, Snail-1, ZEB-1, ZEB-2, and MMP9) and promoted epithelial markers (E-cadherin) while reducing mesenchymal markers (N-cadherin).

CONCLUSION

In conclusion, the induction of apoptosis and the inhibition of EGFR/ERK/P38/NF-κB signaling are correlated with lenvatinib's ability to hinder tumor progression and enhance the cytotoxic effects of cisplatin in bladder cancer. These findings underscore the potential of lenvatinib as a therapeutic option for bladder cancer, either as a standalone treatment or in combination with cisplatin.

Establishment of a prognostic model to predict chemotherapy response and identification of RAC3 as a chemotherapeutic target in bladder cancer

Cisplatin-based chemotherapy is considered the primary treatment option for patients with advanced bladder cancer (BCa). However, the objective response rate to chemotherapy is often unsatisfactory, leading to a poor 5-year survival rate. Furthermore, current strategies for evaluating chemotherapy response and prognosis are limited and inefficient. In this study, we aimed to address these challenges by establishing a chemotherapy response type gene (CRTG) signature consisting of 9 genes and verified the prognostic value of this signature using TCGA and GEO BCa cohorts. The risk scores based on the CRTG signature were found to be associated with advanced clinicopathological status and demonstrated favorable predictive power for chemotherapy response in the TCGA cohort. Meanwhile, tumors with high risk scores exhibited a tendency toward a "cold tumor" phenotype. These tumors showed a low abundance of T cells, CD8+ T cells and cytotoxic lymphocytes, along with a high abundance of cancer-associated fibroblasts. Moreover, they displayed higher mRNA levels of these immune checkpoints: CD200, CD276, CD44, NRP1, PDCD1LG2 (PD-L2), and TNFSF9. Furthermore, we developed a nomogram that integrated the CRTG signature with clinicopathologic risk factors. This nomogram proved to be a more effective tool for predicting the prognosis of BCa patients. Additionally, we identified Rac family small GTPase 3 (RAC3) as a biomarker in our model. RAC3 was found to be overexpressed in chemoresistant BCa tissues and enhance the chemotherapeutic resistance of BCa cells in vitro and in vivo by regulating the PAK1-ERK1/2 pathway. In conclusion, our study presents a novel CRTG model for predicting chemotherapy response and prognosis in BCa. We also highlight the potential of combining chemotherapy with immunotherapy as a promising strategy for chemoresistant BCa and that RAC3 might be a latent target for therapeutic intervention.

Unveiling nature's potential weapon: Magnolol's role in combating bladder cancer by upregulating the miR-124 and inactivating PKC-δ/ERK axis

BACKGROUND

Bladder cancer (BC) is a challenging disease to manage. Researchers have been investigating the potential of magnolol, a compound derived from Magnolia officinalis, as an anti-cancer agent. However, the exact regulatory mechanism of magnolol and its impact on the NF-κB signaling pathway in BC remain unclear.

MATERIALS

To comprehensively evaluate its therapeutic potential, the researchers conducted a series of experiments using BC cell lines (TSGH8301, T24, and MB49) and in vivo animal models.

RESULTS

The results of the study demonstrated that magnolol exhibits cytotoxic effects on BC cells by activating both the extrinsic and intrinsic apoptosis signaling pathways. Additionally, the expression of anti-apoptotic genes was downregulated by magnolol treatment. The researchers also uncovered the regulatory role of PKCδ/ERK and miR-124-3p in the NF-κB pathway, which may be influenced by magnolol. Treatment with magnolol led to the inactivation of PKCδ/ERK and an increase in miR-124-3p expression, effectively inhibiting NF-κB-mediated progression of BC. Importantly, the administration of magnolol did not result in significant toxicity in normal tissues, highlighting its potential as a safe adjunctive therapy with minimal adverse effects.

CONCLUSION

These findings position magnolol as a promising therapeutic agent for the treatment of BC. By activating apoptosis signaling pathways and inhibiting NF-κB pathway through the upregulation of miR-124-3p and downregulation of PKCδ/ERK activation, magnolol holds promise for suppressing tumor progression and improving patient outcomes in BC. Further research and clinical trials are warranted to explore the full potential of magnolol in the future.

Fluoxetine inactivates STAT3/NF-κB signaling and promotes sensitivity to cisplatin in bladder cancer

Bladder cancer is known as one of the top ten most common cancer types worldwide and can be majorly divided into muscles invasive bladder cancer (MIBC) and non-muscles invasive type (NMIBC). However, the prognosis of BC remains poor under standard treatment including radical cystectomy or concurrent chemoradiotherapy. Numerous studies have reported that the prognosis of BC is associated with the activation of signal transducer and activator of transcription (STAT3) and nuclear factor kappa-B (NF-κB). Fluoxetine, a well-known anti-depressant, has been reported to against various type of cancers. However, it is unclear whether fluoxetine has the capacity to inhibit BC progression by targeting STAT3 and NF-κB-mediated signaling. Here, we used cell viability, apoptosis assay, wound healing assay, invasion/migration assay, Western blotting assay, immunofluorescence staining, as well as animal experiments, to elucidate the efficacy of fluoxetine on in vitro and in vivo BC models. We found that fluoxetine may induce cytotoxicity and intrinsic/extrinsic apoptosis in BC and enhance the potential of cisplatin. Fluoxetine promoted both caspase-dependent and caspase-independent apoptosis signaling by activating caspase-3, 8, 9, apoptosis-inducing factor (AIF), and EndG. Furthermore, fluoxetine suppressed invasion and migration ability and the expression of metastasis-associated genes. Fluoxetine was also found to inactivate the phosphorylation of STAT3 (Tyr705) and NF-κB (Ser536) and suppress the nuclear translocation of NF-κB. In MB49-bearing mice, fluoxetine effectively delayed the progression of BC without inducing general toxicity. In summary, the induction of apoptosis and the inhibition of invasion triggered by fluoxetine are associated with the inactivation of STAT3 and NF-κB.

Natural Products as New Approaches for Treating Bladder Cancer: From Traditional Medicine to Novel Drug Discovery

Bladder cancer (BC) is a heterogeneous disease that a tumor develops in the bladder lining and in some cases, the bladder muscle. Chemotherapy and immunotherapy are commonly used to treat bladder cancer. However, chemotherapy can cause burning and irritation in the bladder while BCG immunotherapy, which is the main type of intravesical immunotherapy for bladder cancer, can also cause burning in the bladder and flu-like symptoms. Thus, drugs originating from natural products have attracted much attention due to the reports that they have anti-cancer properties with low adverse effects. In this study, eighty-seven papers that dealt with natural products preventing or treating bladder cancer were reviewed. The studies were classified into the following mechanism: 71 papers on cell death, 5 papers on anti-metastasis, 3 papers on anti-angiogenesis, 1 paper on anti-resistance, and 7 papers on clinical trials. Most of the natural products that induced apoptosis up-regulated proteins such as caspase-3 and caspase-9. Regarding anti-metastasis, MMP-2 and MMP-9 are regulated frequently. Regarding anti-angiogenesis, HIF-1α and VEGF-A are down-regulated frequently. Nevertheless, the number of papers regarding anti-resistance and clinical trial are too few, so more studies are needed. In conclusion, this database will be useful for future in vivo studies of the anti-bladder cancer effect of natural products, in the process of selecting materials used for the experiment.

Tropaeolum majus L. and low dose gamma radiation suppress liver carcinoma development via EGFR-HER2 signaling pathway

Hepatocellular carcinoma (HCC) is one of the most fatal cancers around the world and remain asymptomatic in early stage. An alcoholic extract prepared from leaves of Tropaeolum majus L. (Tropaeolaceae) was assessed for its potential activity against diethylnitrosamine-induced liver carcinoma in vivo. Oral administration of the extract significantly decreased the inflammatory marker translation NF-kB and supressed HCC progression in combination with 0.5 Gy gamma radiation via EGF-HER-2 pathway. Histopathological and immunohistopathological features also showed the recovery of a hepatic architecture. Immunohistochemical study showed the T. majus and LDR enhancement effect on proapoptotic markers (caspase-3 and Bax) and inhibition of anti-apoptotic factor (BCl2). HPLC-DAD-MSⁿ analysis of the extract revealed the annotation of twelve compounds. T. majus could mediate a defensive influence against diethylnitrosamine-induced hepatocarcinogenesis and serve as a respectable option in amelioration of the hepatocellular carcinoma development in combination with low dose of gamma radiation.

Prospective Epigenetic Actions of Organo-Sulfur Compounds against Cancer: Perspectives and Molecular Mechanisms

Major epigenetic alterations, such as chromatin modifications, DNA methylation, and miRNA regulation, have gained greater attention and play significant roles in oncogenesis, representing a new paradigm in our understanding of cancer susceptibility. These epigenetic changes, particularly aberrant promoter hypermethylation, abnormal histone acetylation, and miRNA dysregulation, represent a set of epigenetic patterns that contribute to inappropriate gene silencing at every stage of cancer progression. Notably, the cancer epigenome possesses various HDACs and DNMTs, which participate in the histone modifications and DNA methylation. As a result, there is an unmet need for developing the epigenetic inhibitors against HDACs and DNMTs for cancer therapy. To date, several epigenetically active synthetic inhibitors of DNA methyltransferases and histone deacetylases have been developed. However, a growing body of research reports that most of these synthetic inhibitors have significant side effects and a narrow window of specificity for cancer cells. Targeting tumor epigenetics with phytocompounds that have the capacity to modulate abnormal DNA methylation, histone acetylation, and miRNAs expression is one of the evolving strategies for cancer prevention. Encouragingly, there are many bioactive phytochemicals, including organo-sulfur compounds that have been shown to alter the expression of key tumor suppressor genes, oncogenes, and oncogenic miRNAs through modulation of DNA methylation and histones in cancer. In addition to vitamins and microelements, dietary phytochemicals such as sulforaphane, PEITC, BITC, DADS, and allicin are among a growing list of naturally occurring anticancer agents that have been studied as an alternative strategy for cancer treatment and prevention. Moreover, these bioactive organo-sulfur compounds, either alone or in combination with other standard cancer drugs or phytochemicals, showed promising results against many cancers. Here, we particularly summarize and focus on the impact of specific organo-sulfur compounds on DNA methylation and histone modifications through targeting the expression of different DNMTs and HDACs that are of particular interest in cancer therapy and prevention.

Dietary consumption of cruciferous vegetables and bladder cancer risk: A systematic review and meta-analysis

Objective

Previous studies on the association of cruciferous vegetables intake with bladder cancer risk have reported inconsistent results. We performed the present meta-analysis to summarize evidence on this association and to quantify the potential dose-response relation based on all available cohort studies.

Methods

A comprehensive literature search of relevant articles up to March 2022 was performed in PubMed and EMBASE. The summary risk estimates with 95% confidence intervals for the highest vs. the lowest intake of cruciferous vegetables were calculated. Dose-response meta-analysis was also performed for studies reporting categorical risk estimates for at least three quantitative levels of cruciferous vegetables intake.

Results

We found that the highest cruciferous vegetables intake was not significantly associated with a lower risk of bladder cancer, compared with the lowest cruciferous vegetables intake category (RR = 0.92, 95% CI 0.80–1.06). Linear dose-response meta-analysis indicated that the pooled RRs for 10 g/day or 1 servings/week increment of cruciferous vegetables intake was not significantly associated with a reduced risk of bladder cancer (P = 0.106 and P = 0.147, respectively). There was no evidence of significant publication bias either with Begg’s test (P = 0.386) or Egger’s test (P = 0.253).

Conclusion

The results of this study did not support the hypothesis that dietary cruciferous vegetables intake was associated with a lower risk of bladder cancer. Further large prospective cohort studies are warranted to confirm our preliminary findings.

Hydrogen Sulfide Biology and Its Role in Cancer

Hydrogen sulfide (H2S) is an endogenous biologically active gas produced in mammalian tissues. It plays a very critical role in many pathophysiological processes in the body. It can be endogenously produced through many enzymes analogous to the cysteine family, while the exogenous source may involve inorganic sulfide salts. H2S has recently been well investigated with regard to the onset of various carcinogenic diseases such as lung, breast, ovaries, colon cancer, and neurodegenerative disorders. H2S is considered an oncogenic gas, and a potential therapeutic target for treating and diagnosing cancers, due to its role in mediating the development of tumorigenesis. Here in this review, an in-detail up-to-date explanation of the potential role of H2S in different malignancies has been reported. The study summarizes the synthesis of H2S, its roles, signaling routes, expressions, and H2S release in various malignancies. Considering the critical importance of this active biological molecule, we believe this review in this esteemed journal will highlight the oncogenic role of H2S in the scientific community.

Hsa-miR-30a-3p overcomes the acquired protective autophagy of bladder cancer in chemotherapy and suppresses tumor growth and muscle invasion

Bladder cancer (BC) is the second most common urologic cancer in western countries. New strategies for managing high-grade muscle-invasive bladder cancer (MIBC) are urgently required because MIBC has a high risk of recurrence and poor survival. A growing body of evidence indicates that microRNA has potent antitumorigenic properties in various cancers, and thus, therapeutic strategies based on microRNA may show promising results in cancer therapy. Analysis of The Cancer Genome Atlas (TCGA) database indicated that hsa-miR-30a-3p is downregulated in human BC. Our in vitro investigation demonstrated that hsa-miR-30a-3p suppresses the expression of matrix metalloproteinase-2 (MMP-2) and MMP-9 and reduces the cell invasive potential of BC cells. Furthermore, hsa-miR-30a-3p directly targets ATG5, ATG12, and Beclin 1; this in turn improves the chemosensitivity of BC cells to cisplatin through the repression of protective autophagy. In a tumor-xenograft mice model, hsa-miR-30a-3p suppressed muscle invasion. Cotreatment with hsa-miR-30a-3p enhanced the antitumor effect of cisplatin in reducing tumor growth in BC. The current study provides a novel strategy of using hsa-miR-30a-3p as an adjuvant or replacement therapy in future BC treatment.

Targeting of EIF4EBP1 by miR-99a-3p affects the functions of B lymphocytes via autophagy and aggravates SLE disease progression

Excessive activation of immune cells plays a key role in the pathogenesis of systemic lupus erythematosus (SLE). The regulation of immune cells by miRNAs is a research hotspot. In this study, second-generation high-throughput sequencing revealed a reduction in miR-99a-3p expression in patients with SLE; however, the specific mechanism underlying this phenomenon remains unclear. After transfection with an miR-99a-3p agomir, the proliferation of Ball-1 cells decreased and the levels of their apoptosis increased. The opposite effects were observed in cells transfected with the miR-99a-3p antagomir. Luciferase reporter assay indicated that miR-99a-3p directly targeted EIF4EBP1. Rescue experiments confirmed the proposed interaction between miR-99a-3p and EIF4EBP1. In vitro, in vivo and clinical investigations further confirmed that the miR-99a-3p agomir reduced the expression of EIF4EBP1, LC3B and LAMP-2A. In the in vivo experiments, serum levels of anti-nuclear antibodies, double-stranded DNA, IgE, IgM, IL-6, IL-10 and B lymphocyte stimulator were higher in mice from the antagomir group than those in mice from the MRL/lpr group. Furthermore, the protein and mRNA levels of EIF4EBP1, LC3B and LAMP-2A, the intensity of immunohistochemical staining of EIF4EBP1, LC3B and LAMP-2A, the urinary protein levels, and the C3 immunofluorescence deposition increased in mice from the antagomir group. The upregulation of miR-99a-3p expression protected B cells from EIF4EBP1-mediated autophagy, whilst the downregulation of miR-99a-3p expression induced autophagy via the EIF4EBP1-mediated regulation of the autophagy signalling pathway in B cells isolated from individuals with SLE. Based on these results, miR-99a-3p and EIF4EBP1 may be considered potential targets for SLE treatment.

Targeting miRNA by Natural Products: A Novel Therapeutic Approach for Nonalcoholic Fatty Liver

The increasing prevalence of nonalcoholic fatty liver disease (NAFLD) as multifactorial chronic liver disease and the lack of a specific treatment have begun a new era in its treatment using gene expression changes and microRNAs. This study aimed to investigate the potential therapeutic effects of natural compounds in NAFLD by regulating miRNA expression. MicroRNAs play essential roles in regulating the cell's biological processes, such as apoptosis, migration, lipid metabolism, insulin resistance, and adipocyte differentiation, by controlling the posttranscriptional gene expression level. The impact of current NAFLD pharmacological management, including drug and biological therapies, is uncertain. In this context, various dietary fruits or medicinal herbal sources have received worldwide attention versus NAFLD development. Natural ingredients such as berberine, lychee pulp, grape seed, and rosemary possess protective and therapeutic effects against NAFLD by modifying the gene's expression and noncoding RNAs, especially miRNAs.

Circ_0030586 inhibits cell proliferation and stemness in bladder cancer by inactivating the ERK signaling via miR-665/NR4A3 axis

Increasing evidence reveals that circular RNAs (circRNAs) serve as oncogenes or tumor suppressors in the development of various tumors including bladder cancer (BCa). In this study, we explored the function and mechanism of circ_0030586 (also named circABCC4, ATP binding cassette subfamily C member 4) in BCa. The expression of circ_0030586 was significantly decreased in BCa tissues and cells, as suggested by RT-qPCR. The circular characteristics of circ_0030586 were verified by agarose gel electrophoresis and RNase R treatment. Colony formation, 5-Ethynyl-2'-deoxyuridine and sphere formation assays revealed that overexpression of circ_0030586 suppressed BCa cell proliferation and stemness in vitro. According to xenograft experiment, circ_0030586 overexpression suppressed tumor growth in vivo. Mechanistically, RNA pulldown and luciferase reporter assays were carried out to explore the interaction between genes. Circ_0030586 served as a competing endogenous RNA (ceRNA) for hsa-miR-665 to upregulate the expression of nuclear receptor subfamily 4 group A member 3 (NR4A3) which is a downstream target gene of miR-665 in BCa. MiR-665 exhibited high expression in BCa tissues and cells while NR4A3 expression was downregulated in BCa. MiR-665 overexpression or NR4A3 silencing reversed the suppressive effect of circ_0030586 overexpression on BCa cell proliferation and stemness. Moreover, western blot analysis revealed that circ_0030586 inactivated the extracellular signal-regulated kinase (ERK) pathway by upregulating NR4A3 expression. In conclusion, circ_0030586 inhibits BCa cell proliferation and stemness by serving as a ceRNA for miR-665 to upregulate NR4A3 expression and thus inactivate the ERK signaling.

Thrombospondin-4 promotes bladder cancer cell migration and invasion via MMP2 production

Bladder cancer (BC) is the second most common urological tumour in Western countries. Approximately, 80% of patients with BC will present with non-muscle invasive bladder cancer (NMIBC), whereas a quarter will have muscle invasive disease (MIBC) at the time of BC diagnosis. However, patients with NMIBC are at risk of BC recurrence or progression into MIBC, and an MIBC prognosis is determined by the presence of progression and metastasis. Matrix metalloproteinase 2 (MMP2), a type of matrix metalloproteinase (MMP), plays a major role in tumour invasion and is well-characterized in BC prognosis. In BC, the mechanisms regulating MMP2 expression, and, in turn, promote cancer invasion, have hardly been explored. Thrombospondin-4 (THBS4/TSP4) is a matricellular glycoprotein that regulates multiple biological functions, including proliferation, angiogenesis, cell adhesion and extracellular matrix modelling. Based on the results of a meta-analysis in the Gene Expression Profiling Interactive Analysis 2 database, we observed that TSP4 expression levels were consistent with overall survival (OS) rate and BC progression, with the highest expression levels observed in the advanced stages of BC and associated with poor OS rate. In our pilot experiments, incubation with recombinant TSP4 promoted the migration and invasion in BC cells. Furthermore, MMP2 expression levels increased after recombinant TSP4 incubation. TSP4-induced-MMP2 expression and cell motility were regulated via the AKT signalling pathway. Our findings facilitate further investigation into TSP4 silencing-based therapeutic strategies for BC.

Dietary isothiocyanates inhibit cancer progression by modulation of epigenome

Cell cycle, growth, survival and metabolism are tightly regulated together and failure in cellular regulation leads to carcinogenesis. Several signaling pathways like the PI3K, WNT, MAPK and NFKb pathway exhibit aberrations in cancer and help achieve hallmark capabilities. Clinical research and in vitro studies have highlighted the role of epigenetic alterations in cancer onset and development. Altered gene expression patterns enabled by changes in DNA methylation, histone modifications and RNA processing have proven roles in cancer hallmark acquisition. The reversible nature of epigenetic processes offers robust therapeutic targets. Dietary bioactive compounds offer a vast compendium of effective therapeutic moieties. Isothiocyanates (ITCs) sourced from cruciferous vegetables demonstrate anti-proliferative, pro-apoptotic, anti-inflammatory, anti-migratory and anti-angiogenic effect against several cancers. ITCs also modulate the redox environment, modulate signaling pathways including PI3K, MAPK, WNT, and NFkB. They also modulate the epigenetic machinery by regulating the expression and activity of DNA methyltransferases, histone modifiers and miRNA. This further enhances their transcriptional modulation of key cellular regulators. In this review, we comprehensively assess the impact of ITCs such as sulforaphane, phenethyl isothiocyanate, benzyl isothiocyanate and allyl isothiocyanate on cancer and document their effect on various molecular targets. Overall, this will facilitate consolidation of the current understanding of the anti-cancer and epigenetic modulatory potential of these compounds and recognize the gaps in literature. Further, we discuss avenues of future research to develop these compounds as potential therapeutic entities.

Effects of triclosan on the RedoximiRs/Sirtuin/Nrf2/ARE signaling pathway in mosquitofish (Gambusia affinis)

Triclosan (TCS) has been widely used in daily life for its broad-spectrum antibacterial property and subsequently detected frequently in aquatic waterborne. Environmental relevant concentrations of TCS in water (ng-μg/L) may pose potential unexpected impact on non-target aquatic organisms. In the present work, we investigated the transcriptional responses of Nrf2 as well as its downstream genes, sirtuins and redox-sensitive microRNAs (RedoximiRs) in livers of the small freshwater fish mosquitofish (Gambusia affinis) which were exposed to environmental relevant concentrations of TCS (0.05 μg/L, 0.5 μg/L and 5 μg/L for 24 h and 168 h). Results showed there were similar up-regulations in Nrf2 and its target genes (e. g. NQO1, CAT and SOD) at transcriptional, enzymatic and protein levels, reflecting oxidative stress of TCS to mosquitofish. Meanwhile, up-regulations of Sirt1, Sirt2 and down-regulations of miR-34b, miR-200b-5p and miR-21 could modulate antioxidant system via the Nrf2/ARE signaling pathway by the post-transcriptional regulations. Some oxidative stress-related biomarkers displayed in concentration-dependent manners (e. g. NQO1 mRNA, CAT mRNA) and/or time-dependent manners (e. g. GSH contents). This study indicated that the RedoximiRs/Sirtuin/Nrf2/ARE signaling pathway played a crucial role in mosquitofish exposed to TCS, and there might be potentially profound effects for TCS on the aquatic ecological safety.

Molecular Mechanisms of the Anti-Cancer Effects of Isothiocyanates from Cruciferous Vegetables in Bladder Cancer

Bladder cancer (BC) is a representative of urological cancer with a high recurrence and metastasis potential. Currently, cisplatin-based chemotherapy and immune checkpoint inhibitors are used as standard therapy in patients with advanced/metastatic BC. However, these therapies often show severe adverse events, and prolongation of survival is unsatisfactory. Therefore, a treatment strategy using natural compounds is of great interest. In this review, we focused on the anti-cancer effects of isothiocyanates (ITCs) derived from cruciferous vegetables, which are widely cultivated and consumed in many regions worldwide. Specifically, we discuss the anti-cancer effects of four ITC compounds—allyl isothiocyanate, benzyl isothiocyanate, sulforaphane, and phenethyl isothiocyanate—in BC; the molecular mechanisms underlying their anti-cancer effects; current trends and future direction of ITC-based treatment strategies; and the carcinogenic potential of ITCs. We also discuss the advantages and limitations of each ITC in BC treatment, furthering the consideration of ITCs in treatment strategies and for improving the prognosis of patients with BC.