Therapeutic Effects of Curcumin against Bladder Cancer: A Review of Possible Molecular Pathways

Obesity and main urologic cancers: Current systematic evidence, novel biological mechanisms, perspectives and challenges

Urologic cancers (UC) account for 13.1% of all new cancer cases and 7.9% of all cancer-related deaths. A growing body of evidence has indicated a potential causal link between obesity and UC. The aim of the present review is to appraise in a critical and integrative manner evidence from meta-analyses and mechanistic studies on the role of obesity in four prevalent UC (kidney-KC, prostate-PC, urinary bladder-UBC, and testicular cancer-TC). Special emphasis is given on Mendelian Randomization Studies (MRS) corroborating a genetic causal association between obesity and UC, as well as on the role of classical and novel adipocytokines. Furthermore, the molecular pathways that link obesity to the development and progression of these cancers are reviewed. Available evidence indicates that obesity confers increased risk for KC, UBC, and advanced PC (20-82%, 10-19%, and 6-14%, respectively), whereas for TC adult height (5-cm increase) may increase the risk by 13%. Obese females tend to be more susceptible to UBC and KC than obese males. MRS have shown that a higher genetic-predicted BMI may be causally linked to KC and UBC but not PC and TC. Biological mechanisms that are involved in the association between excess body weight and UC include the Insulin-like Growth Factor axis, altered availability of sex hormones, chronic inflammation and oxidative stress, abnormal secretion of adipocytokines, ectopic fat deposition, dysbiosis of the gastrointestinal and urinary tract microbiomes and circadian rhythm dysregulation. Anti-hyperglycemic and non-steroidal anti-inflammatory drugs, statins, and adipokine receptor agonists/antagonists show potential as adjuvant cancer therapies. Identifying obesity as a modifiable risk factor for UC may have significant public health implications, allowing clinicians to tailor individualized prevention strategies for patients with excess body weight.

Curcumin in the treatment of urological cancers: Therapeutic targets, challenges and prospects

Urological cancers include bladder, prostate and renal cancers that can cause death in males and females. Patients with urological cancers are mainly diagnosed at an advanced disease stage when they also develop resistance to therapy or poor response. The use of natural products in the treatment of urological cancers has shown a significant increase. Curcumin has been widely used in cancer treatment due to its ability to trigger cell death and suppress metastasis. The beneficial effects of curcumin in the treatment of urological cancers is the focus of current review. Curcumin can induce apoptosis in the three types of urological cancers limiting their proliferative potential. Furthermore, curcumin can suppress invasion of urological cancers through EMT inhibition. Notably, curcumin decreases the expression of MMPs, therefore interfering with urological cancer metastasis. When used in combination with chemotherapy agents, curcumin displays synergistic effects in suppressing cancer progression. It can also be used as a chemosensitizer. Based on pre-clinical studies, curcumin administration is beneficial in the treatment of urological cancers and future clinical applications might be considered upon solving problems related to the poor bioavailability of the compound. To improve the bioavailability of curcumin and increase its therapeutic index in urological cancer suppression, nanostructures have been developed to favor targeted delivery.

Chitosan-based nanoscale systems for doxorubicin delivery: Exploring biomedical application in cancer therapy

Green chemistry has been a growing multidisciplinary field in recent years showing great promise in biomedical applications, especially for cancer therapy. Chitosan (CS) is an abundant biopolymer derived from chitin and is present in insects and fungi. This polysaccharide has favorable characteristics, including biocompatibility, biodegradability, and ease of modification by enzymes and chemicals. CS-based nanoparticles (CS-NPs) have shown potential in the treatment of cancer and other diseases, affording targeted delivery and overcoming drug resistance. The current review emphasizes on the application of CS-NPs for the delivery of a chemotherapeutic agent, doxorubicin (DOX), in cancer therapy as they promote internalization of DOX in cancer cells and prevent the activity of P-glycoprotein (P-gp) to reverse drug resistance. These nanoarchitectures can provide co-delivery of DOX with antitumor agents such as curcumin and cisplatin to induce synergistic cancer therapy. Furthermore, co-loading of DOX with siRNA, shRNA, and miRNA can suppress tumor progression and provide chemosensitivity. Various nanostructures, including lipid-, carbon-, polymeric- and metal-based nanoparticles, are modifiable with CS for DOX delivery, while functionalization of CS-NPs with ligands such as hyaluronic acid promotes selectivity toward tumor cells and prevents DOX resistance. The CS-NPs demonstrate high encapsulation efficiency and due to protonation of amine groups of CS, pH-sensitive release of DOX can occur. Furthermore, redox- and light-responsive CS-NPs have been prepared for DOX delivery in cancer treatment. Leveraging these characteristics and in view of the biocompatibility of CS-NPs, we expect to soon see significant progress towards clinical translation.

KLF16 Downregulates the Expression of Tumor Suppressor Gene TGFBR3 to Promote Bladder Cancer Proliferation and Migration

Introduction

Krüppel-like factors (KLFs), which comprise 17 family members, exert important functions during the development of cancer. The role of KLF16 seems controversial in carcinogenesis because both tumor suppressive and promoting effects have been reported.

Methods

The expression level of KLF16 was analyzed based on public data sets from The Cancer Genome Atlas (TCGA) and evaluated by immunohistochemical (IHC) staining. CCK8 assay, colony formation analysis, transwell assays and the PI/Annexin V-APC assay kit were performed to detect cell growth, colony formation, cell migration and apoptosis of BC cells. Xenograft tumorigenesis assay was performed to detect the KLF16 expression on BC growth in vivo. Dual-luciferase reporter assay and chromatin immunoprecipitation (ChIP)-qPCR assay were performed to analyze the interaction between KLF16 and its target.

Results

In this study, we explored the role of KLF16 in bladder cancer (BC). We demonstrated that KLF16 was overexpressed in human BC tissues. The high expression of KLF16 was a potential predictor of a poor prognosis in patients with BC. Interference with KLF16 expression in 563 cells, having relatively higher levels of KLF16, repressed cell proliferation and migration. In contrast, upregulation of KLF16 in T24 cells enhanced cellular function, including cell growth and migration. KLF16 also suppressed the apoptosis of BC cells. Additionally, KLF16 inhibited the expression of the TGF-type III receptor (TGFBR3) by binding to its promoter sequence and reducing transcriptional activity. There was a negative correlation between KLF16 and TGFBR3 in human BC tissues. Furthermore, TGFBR3 was revealed to be a negative regulator of BC cell proliferation and migration. KLF16 also supported BC tumorigenesis by downregulating TGFBR3 expression in vivo.

Discussion

These results suggested that KLF16 acts as an oncogene in BC through transcriptional inactivation of TGFBR3. This study provides evidence that targeting the KLF16/TGFBR3 axis may be beneficial for BC patients.

Curcumin biosynthesis from ferulic acid by engineered Saccharomyces cerevisiae

BACKGROUND AND GOAL

Curcumin is a polyphenolic compound found in Curcuma longa. This bioactive molecule has several reported health-benefit effects, being the anticarcinogenic activity among the most promising ones. However, curcumin extraction from natural sources is hampered by impure products obtained from harsh chemicals and limited by plant seasonality and high prices. Therefore, curcumin heterologous production emerged as an interesting alternative. Escherichia coli has been explored as chassis but the implementation of the pathway in Saccharomyces cerevisiae can have several advantages, including its generally regarded as safe status. Hence, S. cerevisiae was engineered for the first time to produce curcumin from its precursor ferulic acid.

METHODS AND RESULTS

The enzymes 4-coumarate-CoA ligase (4CL1) from Arabidopsis thaliana or feruloyl-CoA synthetase (FerA) from Pseudomonas paucimobilis and type III polyketide synthases (PKSs) from Oryza sativa or C. longa were expressed in BY4741 strain. To avoid ferulic acid deviation, the gene FDC1 coding a ferulic acid decarboxylase was deleted. The maximum curcumin titer was obtained with FerA combined with C. longa PKSs (2.7 mg L^-1 ).

CONCLUSIONS AND IMPLICATIONS

Up to our knowledge, this is the first work reporting the expression of a feruloyl-CoA synthase and also curcuminoid biosynthetic enzymes in S. cerevisiae, and consequently, curcumin production.

Sinomenine Inhibits the Progression of Bladder Cancer Cells by Downregulating LncRNA-HEIH Expression

Background

Sinomenine has been reported to effectively repress the progression of lung cancer and breast cancer. However, the effects of sinomenine in bladder cancer are not well understood. The purpose of this study was to evaluate the effects of sinomenine in bladder cancer.

Methods

The mRNA expression of HEIH in bladder cancer cells was measured by RT-qPCR. T24 and SW780 cells were treated with sinomenine for 24 hours. Cell viability was detected by the MTT assay. Cell migration and invasion were detected by the transwell assay. Western blotting assay was performed to assess the protein expression of Bcl-2, Bax, and caspase-3.

Results

Sinomenine significantly suppressed cell viability in T24 and SW780 cells. Moreover, cell migration and invasion were significantly inhibited by sinomenine. Sinomenine accelerated the expression of Bax and caspase-3 but decreased the expression of Bcl-2. HEIH was upregulated in bladder cancer cells compared with normal bladder epithelial cells. Besides this, we noticed that HEIH knockdown blocked cell proliferation, migration, and invasion but facilitated cell apoptosis in bladder cancer cells. Additionally, HEIH reversed the suppression of the progression induced by sinomenine.

Conclusion

Sinomenine was observed to suppress cell progression of bladder cancer cells by inhibiting HEIH expression. Our findings suggested that the use of sinomenine might be an effective treatment for bladder cancer.

Curcumin and its derivatives in cancer therapy: Potentiating antitumor activity of cisplatin and reducing side effects

Curcumin is a phytochemical isolated from Curcuma longa with potent tumor-suppressor activity, which has shown significant efficacy in pre-clinical and clinical studies. Curcumin stimulates cell death, triggers cycle arrest, and suppresses oncogenic pathways, thereby suppressing cancer progression. Cisplatin (CP) stimulates DNA damage and apoptosis in cancer chemotherapy. However, CP has adverse effects on several organs of the body, and drug resistance is frequently observed. The purpose of the present review is to show the function of curcumin in decreasing CP's adverse impacts and improving its antitumor activity. Curcumin administration reduces ROS levels to prevent apoptosis in normal cells. Furthermore, curcumin can inhibit inflammation via down-regulation of NF-κB to maintain the normal function of organs. Curcumin and its nanoformulations can reduce the hepatoxicity, neurotoxicity, renal toxicity, ototoxicity, and cardiotoxicity caused by CP. Notably, curcumin potentiates CP cytotoxicity via mediating cell death and cycle arrest. Besides, curcumin suppresses the STAT3 and NF-ĸB as tumor-promoting pathways, to enhance CP sensitivity and prevent drug resistance. The targeted delivery of curcumin and CP to tumor cells can be mediated nanostructures. In addition, curcumin derivatives are also able to reduce CP-mediated side effects, and increase CP cytotoxicity against various cancer types.

Comparation of Anti-Inflammatory and Antioxidantactivities of Curcumin, Tetrahydrocurcuminand Octahydrocurcuminin LPS-Stimulated RAW264.7 Macrophages

Curcumin (CUR) possesses pronounced anti-inflammatory and antioxidant activities. Generally, the clinical application of CUR is restricted due to its apparent unstability and poor absorption, and the biological activities of CUR may be closely associated with its metabolites. Tetrahydrocurcumin (THC) and octahydrocurcumin (OHC) are two major hydrogenated metabolites of CUR with appreciable biological potentials. Here, we comparatively explored the anti-inflammatory and antioxidant activities of CUR, THC, and OHC in lipopolysaccharide- (LPS-) induced RAW264.7 macrophages. The results revealed that CUR, THC, and OHC dose-dependently inhibited the generation of NO and MCP-1 as well as the gene expression of MCP-1 and iNOS. Additionally, CUR, THC, and OHC significantly inhibited NF-κB activation and p38MAPK and ERK phosphorylation, while substantially upregulated the Nrf2 target gene expression (HO-1, NQO-1, GCLC, and GCLM). Nevertheless, zinc protoporphyrin (ZnPP), a typical HO-1 inhibitor, significantly reversed the alleviative effect of CUR, THC, and OHC on LPS-stimulated ROS generation. These results demonstrated that CUR, THC, and OHC exerted beneficial effect on LPS-stimulated inflammatory and oxidative responses, at least partially, through inhibiting the NF-κB and MAPKs pathways and activating Nrf2-regulated antioxidant gene expression. Particularly, THC and OHC might exert superior antioxidant and anti-inflammatory activities to CUR in LPS-stimulated RAW264.7 cells, which can be further explored to be a promising novel effective agent for inflammatory treatment.

Inhibitory Effects of Apigenin on Tumor Carcinogenesis by Altering the Gut Microbiota

The flavonoid apigenin is common to many plants. Although the responsible mechanisms have yet to be elucidated, apigenin demonstrates tumor suppression in vitro and in vivo. This study uses an azoxymethane (AOM)/dextran sodium sulfate- (DSS-) induced colon cancer mouse model to investigate apigenin's potential mechanism of action exerted through its effects upon gut microbiota. The size and quantity of tumors were reduced significantly in the apigenin treatment group. Using 16S rRNA high-throughput sequencing of fecal samples, the composition of gut microbiota was significantly affected by apigenin. Further experiments in which gut microbiota were reduced and feces were transplanted provided further evidence of apigenin-modulated gut microbiota exerting antitumor effects. Apigenin was unable to reduce the number or size of tumors when gut microbiota were depleted. Moreover, tumor inhibition effects were initiated following the transplant of feces from mice treated with apigenin. Our findings suggest that the effect of apigenin on the composition of gut microbiota can suppress tumors.