Nonthermal and reversible control of neuronal signaling and behavior by midinfrared stimulation.

Various neuromodulation approaches have been employed to alter neuronal spiking activity and thus regulate brain functions and alleviate neurological disorders. Infrared neural stimulation (INS) could be a potential approach for neuromodulation because it requires no tissue contact and possesses a high spatial resolution. However, the risk of overheating and an unclear mechanism hamper its application. Here we show that midinfrared stimulation (MIRS) with a specific wavelength exerts nonthermal, long-distance, and reversible modulatory effects on ion channel activity, neuronal signaling, and sensorimotor behavior. Patch-clamp recording from mouse neocortical pyramidal cells revealed that MIRS readily provides gain control over spiking activities, inhibiting spiking responses to weak inputs but enhancing those to strong inputs. MIRS also shortens action potential (AP) waveforms by accelerating its repolarization, through an increase in voltage-gated K+ (but not Na+) currents. Molecular dynamics simulations further revealed that MIRS-induced resonance vibration of -C=O bonds at the K+ channel ion selectivity filter contributes to the K+ current increase. Importantly, these effects are readily reversible and independent of temperature increase. At the behavioral level in larval zebrafish, MIRS modulates startle responses by sharply increasing the slope of the sensorimotor input-output curve. Therefore, MIRS represents a promising neuromodulation approach suitable for clinical application.

450-nm blue diode laser: a novel medical apparatus for upper tract urothelial lesions.

OBJECTIVE: To explore the feasibility, safety and effectiveness of the 450-nm blue diode laser (BL), novel blue laser in the treatment of upper tract urothelial carcinomas (UTUCs) and other lesions in a porcine model. MATERIAL AND METHODS: For in vitro experiment, the ureter tissue was vaporised and coagulated with BL, green-light laser (GL) and Ho:YAG laser (Ho). The efficiency, width and depth of vaporisation, and depth of coagulation were recorded and compared. For in vivo experiments, four swines weighing 70 kg were used. In the acute group, different modes of operations were performed to evaluate the thermal damage, perforation and bleeding. In the chronic group, the overall appearance of the ureter and laser wound healing were observed by the naked eyes and H&E staining 3 weeks after surgery. RESULTS: In in vitro study, the BL showed a higher efficiency of tissue vaporisation and less tissue coagulation for fresh ureter compared to GL and Ho. In the in vivo study, the power of BL set at 7 W was better, and the thickness of thermal damage varied with different surgery types in the range of 74-306 µm. After 3 weeks, the wound healed well static in vaporisation (SV), moving vaporisation (MV) and H&E staining indicated mucosal healing rather than scar healing. CONCLUSION: 5-10W blue diode laser achieved a higher efficiency of tissue vaporisation and less tissue coagulation in a porcine model, indicating its potential application in the endoscopic surgery of UTUC as an optional device with high performance and safety.

Driving DNA Origami Assembly with a Terahertz Wave.

Terahertz (THz) waves show nontrivial interactions with living systems, but the underlying molecular mechanisms have yet to be explored. Here, we employ DNA origami as a model system to study the interactions between THz waves and DNA structures. We find that a 3-min THz illumination (35.2 THz) can drive the unwinding of DNA duplexes at ∼10 °C below their melting point. Computational study reveals that the THz wave can resonate with the vibration of DNA bases, provoking the hydrogen bond breaking. The cooperation of thermal and nonthermal effects allows the unfolding of undesired secondary structures and the THz illumination can generate diverse DNA origami assemblies with the yield (>80%) ∼ 4-fold higher than that by the contact heating at similar temperatures. We also demonstrate the in situ assembly of DNA origami in cell lysate. This method enables remotely controllable assembly of intact biomacromolecules, providing new insight into the bioeffects of THz waves.

High-power 450 nm blue diode laser for endoscopic mucosal resection/endoscopic submucosal dissection in the stomach: Preliminary results on a porcine model with a modified flexible endoscope.

BACKGROUND: Due to the precise vaporization of the novel 450 nm blue diode laser in soft tissues (i.e., bladder and colon) in our previous studies, porcine stomach tissues were applied here to certify its efficacy in endoscopic mucosal resection (ESR)/endoscopic submucosal dissection (ESD) for hypothetical lesions ex vivo and in vivo. MATERIALS AND METHODS: In an ex vivo study of ESR, 20 pieces of tissues (8 cm × 6 cm) from 7 fresh stomachs after spraying saline were vaporized with a three-dimensional scanning system using the blue diode laser at a maximum of 30 W, a different treatment speed and working distance (WD). In ex vivo ESD, 18 pieces of tissues from 6 fresh stomachs were used and the same laser parameters were used to perform the procedure. The depth, width, and coagulation of the laser vaporization were measured. Furthermore, the large scales (2.0 cm × 1.5 cm) for 18 hypothetical lesions of the gastric mucosa and submucosa of the 6 fresh stomachs were also resected with a modified flexible endoscope. In vivo, six hypothetical lesions of six porcine were vaporized by the novel blue laser, and the resultant lesions at the acute and chronic stages were assessed by the naked eye and hematoxylin and eosin staining. RESULTS: In the contact mode, more tissue was vaporized, and the thickness of the coagulation was stable when the WD was 0-2 mm, whose value varied from 0.33 to 1.73 mm. In the gastroscopy model, the mean thickness of coagulation from the mucosa was 0.67 mm, and a significant carbonization zone was not observed. In vivo, the laser beam could accurately act on the hypothetical target. No bleeding and clear vision were present in the procedure. After 3 weeks, tissue healing was well recovered after laser coagulation, resection, and submucosal dissection. CONCLUSIONS: In the present study, the novel 450 nm blue diode laser exhibited ideal vaporization and thinner coagulation thickness in the porcine stomach, which indicated that it could be alternately used as a new device for stomach lesions.

Use of Circulating Tumor DNA for the Clinical Management of Metastatic Castration-Resistant Prostate Cancer: A Multicenter, Real-World Study.

BACKGROUND: This study aimed to describe the aberrations of DNA damage repair genes and other important driving genes in Chinese patients with metastatic castration-resistant prostate cancer (mCRPC) using circulating tumor (ctDNA) sequencing and to evaluate the associations between the clinical outcomes of multiple therapies and key genomic alterations in mCRPC, especially DNA damage repair genes. PATIENTS AND METHODS: A total of 292 Chinese patients with mCRPC enrolled from 8 centers. Multigene targeted sequencing was performed on 306 ctDNA samples and 23 matched tumor biopsies. The frequency of genomic alterations were compared with the Stand Up to Cancer-Prostate Cancer Foundation (SU2C-PCF) cohort. The Kaplan-Meier method was used to evaluate progression-free survival (PFS) following standard systemic treatments for mCRPC. Cox regression analyses were performed to determine prognostic factors associated with PFS resulting from treatments for mCRPC. RESULTS: In total, 33 of 36 (91.7%) mutations were found consistently between ctDNA and paired biopsy samples. The most common recurrent genomic alterations were found in AR (34.6%), TP53 (19.5%), CDK12 (15.4%), BRCA2 (13%), and RB1 (5.8%). The frequency of CDK12 alterations (15.4%) in our cohort was significantly higher than that in Western populations (5%-7%). AR amplification and TP53 and/or RB1 alterations were associated with resistance to abiraterone or docetaxel. Patients with a CDK12 defect showed rapid disease progression after abiraterone treatment. However, the clinical outcome after docetaxel treatment was similar between patients with and without CDK12 defects. In multivariate Cox regression analysis, a CDK12 defect was significantly associated with inferior PFS after abiraterone treatment. Patients with a BRCA2 defect showed marked response to both PARP inhibitors and platinum-based chemotherapy. CONCLUSIONS: Our study explored the genomic landscape of Chinese patients with mCRPC at different treatment stages using minimally invasive methods and evaluated the clinical implications of the driver genomic alterations on patients' response to the most widely used therapies for mCRPC. We observed a significantly higher alteration frequency of CDK12 in our cohort compared with the SU2C-PCF cohort.

Management of highly recurrent bladder neck contractures via transurethral resection combined with intra- and post-operative triamcinolone acetonide injections.

PURPOSE: To present our preliminary experience in managing patients with highly recurrent bladder neck contractures (BNCs) after transurethral resection of the prostate (TURP). METHODS: Between February 2015 and March 2018, 28 patients with highly recurrent BNCs who had failed multiple prior to endoscopic treatments were managed with transurethral resection and intra- and post-operative triamcinolone acetonide injections. The scar tissue was resected to the circular fiber at the bladder neck, and triamcinolone acetonide (2 mL, 40 mg/mL) was injected at the incision sites (8 points) using a cystoscopic injection needle. The cystoscopy-guided injections were repeated every four weeks for total three times after surgery. The patients were followed up at 3, 6, 12 months after surgery, and in July-August 2019. RESULTS: The recurrent interval before the treatments was 2.2 ± 1.2 months, without any BNC recurrence in the first 12 weeks after transurethral resection. The urinary flow rate increased significantly and was maintained during the follow-up period. Adequate voiding function was reported in 25 of 28 patients at a median follow-up of 2.8 (1.7, 3.9) years. One of the three patients with decreased urinary flow rate had underactive detrusor and no BNC recurrence. The complications were mild and tolerable. CONCLUSION: Transurethral resection of the scar tissue combined with intra- and post-operative triamcinolone acetonide injections resulted in a success rate of 92.9% in patients with highly recurrent BNC following TURP. It is a simple, safe, and effective treatment for highly recurrent BNCs.

PSA nadir and time to PSA nadir during initial androgen deprivation therapy as prognostic factors in metastatic castration-resistance prostate cancer patients treated with docetaxel.

Prostate-specific antigen nadir (nPSA) and time to nPSA (TTN) have been proved to be associated with the prognosis of prostate cancer. In this study, we explored the prognosis effect of nPSA and TTN during initial androgen deprivation therapy (ADT) in patients with metastatic castration-resistant prostate cancer (mCRPC) after treatment with docetaxel-based chemotherapy. The data of 153 mCRPC patients received docetaxel followed by ADT were retrospectively reviewed. Multivariate Cox regression analysis demonstrated that TTN (overall survival (OS): Hazard ratio [HR] 0.096, 95% confidence interval [CI] 0.045-0.206, p < .001; progression-free survival (PFS): HR 0.128, 95% CI 0.078-0.211, p < .001) and nPSA (OS: HR 2.849, 95% CI 1.318-6.157, p = .008; PFS: HR 1.573, 95% CI 1.008-2.454, p = .046) acted as independent predictors of chemotherapy prognosis. Kaplan-Meier analysis showed that patients with nPSA ≥ 0.2 ng/ml or TTN < 6.5 months had shorter OS and PFS. These results suggest that TTN and nPSA during ADT can affect the prognosis of docetaxel-based chemotherapy prognosis post-castration resistance in patients with mCRPC, and higher nPSA and shorter TTN lead to poor chemotherapy prognosis. What is more, TTN has a greater impact during ADT on the prognosis of chemotherapy than nPSA.

Green-light laser en bloc resection versus conventional transurethral resection for initial non-muscle-invasive bladder cancer: A randomized controlled trial.

OBJECTIVE: To compare the safety and outcomes between green-light laser en bloc resection and transurethral resection of bladder tumor. METHODS: A single-center, randomized controlled trial was carried out from August 2014 to September 2018. Patients with initial non-muscle-invasive bladder cancer were randomized to green-light laser en bloc resection or transurethral resection of bladder tumor. The primary outcomes were pathological findings and perioperative events. The secondary outcome was tumor recurrence. RESULTS: A total of 233 patients were randomized to the transurethral resection of bladder tumor group (117 patients) and the green-light laser en bloc resection group (116 patients). The resection time was longer in the green-light laser en bloc resection group (P = 0.022); however, no differences were identified in overall operative time (P = 0.255). Nine patients (7.7%) had an obturator nerve reflex during transurethral resection of bladder tumor. The estimated volume of blood loss was significantly lower in the green-light laser en bloc resection group (P = 0.012). The green-light laser en bloc resection group had a higher rate of T1 bladder cancer (P = 0.031). A total of 104 patients (89.7%) treated with green-light laser en bloc resection had detrusor muscle presence in the specimen, whereas 37 (31.9%) patients had the presence of muscularis mucosae, which was significantly higher than the corresponding number of transurethral resection of bladder tumor patients (P = 0.005 and 0.002, respectively). After a median follow-up period of 48 months, just five patients had tumor recurrence (three in the transurethral resection of bladder tumor group and two in the green-light laser en bloc resection group), and there was no difference between these two groups. CONCLUSIONS: Compared with transurethral resection of bladder tumor, green-light laser en bloc resection is more effective due to less obturator nerve reflex and the same recurrence rate. Most importantly, green-light laser en bloc resection can provide better tumor specimens for pathological examinations.

The AKR1C3/AR-V7 complex maintains CRPC tumour growth by repressing B4GALT1 expression.

Multiple mechanisms contribute to the survival and growth of metastatic castration-resistant prostate cancer (mCRPC) cells without androgen, including androgen receptor splice variants (AR-V) and de novo intratumoral androgen synthesis. AKR1C3 is a critical androgenic enzyme that plays different roles in mCRPC, such as an EMT driver or AR coactivator. However, the relationship and regulatory mechanisms between AKR1C3 and AR-V remain largely unknown. In this study, we observed a positive correlation between AKR1C3 and AR-V7 staining in tissues from prostate rebiopsy at mCRPC. Mechanistically, AKR1C3 interacts with AR-V7 protein in CRPC cells, which can reciprocally inhibit AR-V7 and AKR1C3 protein degradation. Biologically, this complex is essential for in vitro and in vivo tumour growth of CRPC cells after androgen deprivation as it represses B4GALT1, a unique tumour suppressor gene in PCa. Together, this study reveals AKR1C3/AR-V7 complex as a potential therapeutic target in mCRPC.

p62 promotes bladder cancer cell growth by activating KEAP1/NRF2-dependent antioxidative response.

p62 is associated with 2 major cellular defense mechanisms against metabolic and oxidative stress, autophagy and the Kelch-like ECH-associated protein 1 (KEAP1)-nuclear factor-E2-related factor 2 (NRF2) system. Recent studies indicate that the p62-KEAP1-NRF2 pathway promotes tumorigenesis and tumor growth mediated by NRF2-dependent antioxidative response. However, whether p62 is involved in bladder cancer (BCa) development remains unknown. Here, we found that p62 is overexpressed in BCa tissue and several BCa cell lines. The knockdown of p62 inhibits BCa cell growth both in vitro and in vivo, with increased intracellular reactive oxygen species level. Mechanically, p62 activates NRF2 signaling by sequestrating KEAP1, which leads to the upregulation of antioxidant genes (Gclc, Gstm5, and Gpx2), thus protecting BCa cells from oxidative stress. Our findings indicate that p62 might be involved in the development of BCa and serve as a potential therapeutic target.

Activation of type 4 metabotropic glutamate receptor promotes cell apoptosis and inhibits proliferation in bladder cancer.

Bladder cancer, the second most common genitourinary malignancy, severely endangers the human health. Rising evidence suggests that metabotropic glutamate receptors (mGluRs) are involve in tumor progression. In this study, we observed that metabotropic glutamate receptor 4 (mGluR4) was functionally expressed in normal and cancerous bladder cells and its expression was positively correlated with high bladder cancer grading. We further confirmed that the activation of mGluR4 by VU0155041, an mGluR4-specific agonist, decreased cyclic adenosine monophosphate (cAMP) concentration and cell viability, promoted apoptosis and inhibited proliferation in bladder cancer cells, whereas MSOP (group III mGluR antagonist) or mGluR4 knockdown eliminated the effects of mGluR4 activity. Western blotting revealed the decreased cyclin D1 expression, increased procaspase-8/9/3 cleavage, and unbalanced Bcl-2/Bax expression in bladder cancer cell lines after mGluR4 activation, and likewise MSOP and mGluR4 knockdown abrogated the actions of mGluR4 activity. In vivo study showed that mGluR4 activation significantly inhibited tumor growth of bladder cancer via suppressing proliferation and promoting apoptosis. Furthermore, upregulation of phosphatase and tensin homolog (PTEN) and inhibition of Akt phosphorylation were also observed after mGluR4 activation. Similar with VU0155041, the Akt-specific inhibitor markedly promoted apoptosis and inhibited proliferation. Nevertheless, the PTEN-specific inhibitor significantly abolished the mGluR4 activation-induced cell apoptosis and proliferative inhibition in bladder cancer cell lines. These results indicate that mGluR4 can regulate the switch between survival and death via the cAMP/PTEN/AKT signaling pathway in bladder cancer cells. Our findings suggest that mGluR4 has diagnostic and prognostic potential for bladder cancer, and the development of mGluR4 agonist may be a promising strategy for bladder cancer treatment.

En bloc resection improves the identification of muscularis mucosae in non-muscle invasive bladder cancer.

PURPOSE: The T1 substage, according to the relationship between muscularis mucosae (MM) and tumors, is a promising prognostic factor for T1 bladder cancer. However, the identification rate of MM is low in specimens, and it is, therefore, not widely used in clinical practice. In this study, we investigated whether en bloc resection of non-muscle invasive bladder cancer (NMIBC) could improve the identification of muscularis mucosae (MM), which may further accurate identification of the T1 substage. PATIENTS AND METHODS: Specimens from 158 patients with primary NMIBC were retrospectively reviewed by two independent pathologists to assess the presence of MM and stratify the T1 substage. Of 158 specimens, 70 specimens were obtained via TURBt with a plasma kinetic loop and 88 were obtained via front-firing potassium-titanyl-phosphate (KTP) green-light laser en bloc resection. Univariable and multivariable logistic regression models were used to analyze the relationship between the clinical characteristics and the presence of MM. RESULTS: The mean age was 58.22 years (range 18-85 years). Multivariable logistic regression analysis showed that the KTP laser resection method was associated with the presence of MM in specimens (P = 0.008). In addition, tumors with smaller sizes, which could also be en bloc resected with TURBt (e.g., ≤1 cm), had a higher presence of MM (P = 0.047). CONCLUSIONS: En bloc resection improves the identification rate of MM, which may enhance the accurate identification of the T1 substage.

Green-laser assisted laparoscopic partial cystectomy for selective muscle-invasive bladder cancer: technique and initial outcome.

PURPOSE: To describe a green-laser marking technique to assist partial cystectomy, which allows accurate identification of tumour margins, and provide our initial experience with ten patients. METHODS: Between January 2014 and February 2018, ten patients suspected with muscle-invasive bladder cancer and request of bladder-preserving treatment were selected. In each case, bilateral pelvic lymphadenectomy was performed before green-laser assisted laparoscopic partial cystectomy. Under the direct view of cystoscope, the front-firing green-laser incision was performed 0.5-1 cm away from the exterior margin of lesion with adequate depth into the fat tissue. Tumours were then en bloc removed via laparoscope under the tracing of laser beam. RESULTS: The location of 12 tumours in 10 patients was superior wall in 7 cases, lateral wall in 3 cases, anterior wall in 1 case, and posterior wall in 1 case. All procedures were completed without serious complications. The median operating time was 270 (210-360) min with a median haemoglobin decrease of 11 (3-38) g/L. Nine patients were high-grade transitional cell carcinoma and one patient was urachal carcinoma, and the clinical stage was pT1 in 1 case, pT2 in 4 cases, and pT3 in 5 cases. The pathological evaluation of tumour margins was negative in 10 patients. During the follow-up, no recurrence or metastasis were detected in 8 patients, but 2 patients presented regional recurrence. CONCLUSION: The use of green-laser marking technique during laparoscopic partial cystectomy is a feasible manoeuvre in assisting the accurate incision and minimizing injury to the remaining bladder.

A novel 450-nm blue laser system for surgical applications: efficacy of specific laser-tissue interactions in bladder soft tissue.

Low-power blue laser allows clean cutting with little bleeding and no undesired coagulations in adjacent tissues; however, studies on high-power blue laser soft tissue ablation properties, including vaporization and coagulation, have not been reported yet. The purpose of this study is to evaluate and analyze the ablation efficacy and coagulation properties of bladder epithelium tissues with a 30-W 450-nm wavelength blue laser. Well-designed ex vivo experiments compared blue laser and 532-nm LBO green laser, both with laser power up to 30 W, for porcine bladder tissue vaporization and coagulation at different experimental parameter settings. At working distance of 1 mm and sweeping speed of 1.5 mm/s, the vaporization efficiency of blue laser and green laser was 5.14mm3/s and 1.20mm3/s, while the depth of coagulation layer was 460 ± 70 µm and 470 ± 80 µm, respectively. We found both blue laser and green laser have excellent efficacy of tissue vaporization and similar tissue coagulation properties. Moreover, in a set of in vivo experiments simulated laser transurethral resection (TUR) surgery on dogs, we found both blue laser and green laser exhibited similar and satisfactory vaporization and coagulation outcomes. Taken together, our results demonstrate that a 450-nm wavelength high-power diode blue laser, like 532-nm wavelength green laser, is capable to produce high efficient tissue vaporization, low-laser tissue penetration, good tissue coagulation, and has low thermal damage to adjacent tissues. Therefore, a 30-W blue diode laser could be a new and safe alternative for surgeries of superficial bladder diseases.

Developing new targeting strategy for androgen receptor variants in castration resistant prostate cancer.

The presence of androgen receptor variant 7 (AR-V7) variants becomes a significant hallmark of castration-resistant prostate cancer (CRPC) relapsed from hormonal therapy and is associated with poor survival of CRPC patients because of lacking a ligand-binding domain. Currently, it still lacks an effective agent to target AR-V7 or AR-Vs in general. Here, we showed that a novel class of agents (thailanstatins, TSTs and spliceostatin A analogs) can significantly suppress the expression of AR-V7 mRNA and protein but in a less extent on the full-length AR expression. Mechanistically, TST-D is able to inhibit AR-V7 gene splicing by interfering the interaction between U2AF65 and SAP155 and preventing them from binding to polypyrimidine tract located between the branch point and the 3' splice site. In vivo, TST-D exhibits a potent tumor inhibitory effect on human CRPC xenografts leading to cell apoptosis. The machinery associated with AR gene splicing in CRPC is a potential target for drugs. Based on their potency in the suppression of AR-V7 responsible for the growth/survival of CRPC, TSTs representing a new class of anti-AR-V agents warrant further development into clinical application.

FGF2-mediated reciprocal tumor cell-endothelial cell interplay contributes to the growth of chemoresistant cells: a potential mechanism for superficial bladder cancer recurrence.

Patients with superficial bladder cancer can be definitively cured by one single transurethral resection (TUR) with additional intravesical chemotherapy; however, up to 75 % of cases display frequent and multiple recurrences. One of the major causes of recurrence is that chemotherapeutic drugs used in intravesical regimens may induce chemoresistance. However, the mechanisms by which these chemoresistant cells develop into recurrent tumors remain unclear. Recent clinical evidence revealed that the expression of pro-angiogenic factor FGF2 was associated with early local relapse in patients with superficial bladder cancer. In this study, we conducted a preliminary investigation of the mechanisms of chemoresistant cells mediated bladder cancer recurrence, focusing on FGF2-initiated tumor cell-endothelial cell interaction on chemoresistant cancer cell growth. We found that the expression of FGF2 was increased in chemoresistant bladder cell lines and in bladder tissues after intravesical chemotherapy. Although chemoresistant bladder cells grow slower than parental cells, chemoresistant bladder cancer cells had stronger ability than parental cells to stimulate endothelial cell migration, growth, and tube formation by producing FGF2. Inversely, endothelial cells significantly promoted chemoresistant bladder cancer growth in vitro and in vivo. Thus, targeting chemotherapy-induced FGF2 upregulation may provide a promising approach to manage the recurrence of superficial bladder cancer.

Genetically Modified Food Labeling in China: In Pursuit of a Rational Path.

Facing a tension between the increasing use of genetically engineered or modified food and consumer concerns over the risks associated with GMOs, China has established a GM food labeling regime through regulations-known as Agro-GMO regulations-to protect consumers' right to know. However, the design and enforcement of this GM food labeling regime is problematic. As a result, the labeling regime is ineffective and inconsistent, leaving consumers' rights unprotected. As the recently amended Food Safety Law in China requires GM food labeling for the first time, this article argues that China should replace the current Agro-GMO food labeling scheme with a special regulatory scheme. A comparative analysis of the GM food labeling systems in the European Union and United States, coupled with a rigorous examination of the problems and barriers of GM food labeling in China, sets a solid foundation by which to propose changes to incorporate into a special regulatory scheme. To this end, this article engages in such an analysis and recommends practical steps to guide the enactment of a special regulatory scheme. The recommendations comport with China's unique legal and political culture, but also could be used by other national regulatory regimes who permit use of GM food while also being committed to improving consumers' right to know.

[Regulatory effect of Skp2 on the expression and transactivation of the androgen receptor in the progression of castration-resistant prostate cancer].

OBJECTIVE: To determine the expression of Skp2 in different prostate cancer (PCa) cell lines and tissues, and explore its influence on the androgen receptor (AR) signaling pathway and development of castration-resistant prostate cancer (CRPC). METHODS: The expression levels of Skp2 and AR in different PCa cell lines were detected by Western blot. After knockdown of Skp2 in the C4-2 and 22RV1 cells transfected with shRNA, the expressions of AR and P27 were determined and the activity of ARR3-Luc measured by dual-luciferase reporter gene assay following treatment with dihydrotestosterone (DHT). The expressions of AR and Skp2 in human naïve PCa or CRPC specimens were detected by immunohistochemical staining followed by analysis of their differences and correlation. RESULTS: The Skp2 protein expression level was significantly higher in the C4-2 or 22RV1 cells than in the LNCaP cells. DHT treatment increased the expression of Skp2 in the C4-2 cells, but knock-down of Skp2 significantly up-regulated the expression of the well-known downstream protein P27 and down-regulated that of AR. Consistently, DHT treatment increased the activity of ARR3-Luc, while knockdown of Skp2 remarkably decreased it in the C4-2 and 22RV1 cells (P < 0.05). In addition, significantly higher expressions of Skp2 and AR were observed in the CRPC than in the naïve specimens (P < 0.05), with a positive correlation between the two proteins (r = 0.658 1, P < 0.05). CONCLUSION: Skp2 can enhance the expression and transcription activity of the AR protein in CRPC cells or tissues and is promising to be a critical molecular therapeutic target.

Autophagy induction by silibinin positively contributes to its anti-metastatic capacity via AMPK/mTOR pathway in renal cell carcinoma.

Silibinin, a dietary cancer chemopreventive flavonoid from the seeds of milk thistle, has been reported to exhibit anti-metastatic effects on renal cell carcinoma (RCC), but the mechanism underlying this phenomenon is not fully understood. The present study aimed at examining the potential role of autophagy in regulating silibinin-induced anti-metastatic effects on RCC cells. Using RCC ACHN and 786-O cells as a model system in vitro, we found that silibinin treatment increased the expression of LC3-II, resulted in the formation of autophagolysosome vacuoles, and caused a punctate fluorescence pattern with the monomeric red fluorescence protein-enhanced green fluorescence protein-LC3 (mRFP-EGFP-LC3) protein, which all are markers for cellular autophagy. Autophagy flux was induced by silibinin in RCC cells, as determined by LC3 turnover assay. Mechanically, the adenosine 5'-monophosphate activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) pathway was identified as involved in regulation of silibinin-induced autophagy. Furthermore, autophagy induction was demonstrated to positively contribute to silibinin-induced anti-metastatic effects on RCC cells in vitro. Activation of autophagy enhanced silibinin-induced inhibition of migration and invasion of RCC cells, while inhibition of autophagy attenuated it. These findings thus provide new information about the potential link between autophagy and metastasis inhibition induced by silibinin, and the induction of autophagy may shed some light into future treatment strategies for metastatic RCC.

Curcumin promotes KLF5 proteasome degradation through downregulating YAP/TAZ in bladder cancer cells.

KLF5 (Krüppel-like factor 5) plays critical roles in normal and cancer cell proliferation through modulating cell cycle progression. In this study, we demonstrated that curcumin targeted KLF5 by promoting its proteasome degradation, but not by inhibiting its transcription in bladder cancer cells. We also demonstrated that lentivirus-based knockdown of KLF5 inhibited cancer cell growth, while over-expression of a Flag-tagged KLF5 could partially reverse the effects of curcumin on cell growth and cyclin D1 expression. Furthermore, we found that curcumin could down-regulate the expression of Hippo pathway effectors, YAP and TAZ, which have been reported to protect KLF5 protein from degradation. Indeed, knockdown of YAP by small interfering RNA caused the attenuation of KLF5 protein, but not KLF5 mRNA, which was reversed by co-incubation with proteasome inhibitor. A xenograft assay in nude mice finally proved the potent inhibitory effects of curcumin on tumor growth and the pro-proliferative YAP/TAZ/KLF5/cyclin D1 axis. Thus, our data indicates that curcumin promotes KLF5 proteasome-dependent degradation through targeting YAP/TAZ in bladder cancer cells and also suggests the therapeutic potential of curcumin in the treatment of bladder cancer.