Gold-caged copolymer nanoparticles as multimodal synergistic photodynamic/photothermal/chemotherapy platform against lethality androgen-resistant prostate cancer.

Given that there is no effective treatment method for lethality androgen-resistant prostate cancers (ARPC), herein we report a multifunctional gold-caged nanoparticle (PTX-PP@Au NPs) against ARPC through integrating functional organic/inorganic materials to exploit the superiors of gold particles such as photothermal effects (PTT), generating reactive oxygen species (photodynamic effects, PDT), carrying chemotherapeutic agents (chemotherapy effects, CT), and inhibiting ion channel. This synergistic PTT/PDT/CT platform consists of three components: i) the Pluronic-polyethylenimine assembling into micelles to encapsulate drugs and providing reduction sites for gold cage formation through a "green" method, ii) the gold cage with surface plasmon resonance peak at near-infrared (NIR) region in a broad window qualifying the PTT/PDT potentiality, iii) a chemotherapeutic agent paclitaxel (PTX) arresting the tumor cell cycle. As demonstrated, the system has remarkable performance on controlling drug release, blocking TRPV6 cation channel, enhancing cell cycle arrest, elevating temperature and generating ROS, thus improving cellular toxicity along with apoptosis, enhancing tumor targeting, and achieving the therapy to ARPC with low toxicity on liver function and minimal side effects to normal organs. Notably, both PTT and PDT effect are generated under single irradiation situation because of the broad absorbance window, along with limited skin damages. As a specific synergistic platform creatively integrating multiple treatment protocols with negative toxicity, PTX-PP@Au NPs provide a facile, effective, and broadly applicable strategy to deadly ARPC.

In vitro design of mesenchymal to epithelial transition of prostate cancer metastasis using 3D nanoclay bone-mimetic scaffolds.

Nanocomposite scaffolds show extensive applications in regenerative medicine and have shown promise as in vitro analogues of human tissue that can be used for the study of diseases. The complex nature of cancer metastasis is recently investigated using several 3D scaffold models. Herein, we report a polymer-nanoclay-based in vitro tumour model that recapitulates early stage of prostate cancer (PCa) colonization during skeletal metastasis on bone mimetic scaffolds. A unique cell culture system termed as "sequential culture (SC)" has been applied to create a bone-mimetic niche for colonization of PCa cells. Human mesenchymal stem cells (MSCs) were seeded on the bone-mimetic scaffolds, where they differentiated into bone cells and then formed mineralized bone matrix without osteogenic supplements. Further, PCa was seeded on MSCs-seeded scaffolds. Sequentially cultured PCa cells with MSCs formed self-organized multicellular tumoroids with distinct tight cellular junctions and hypoxic core regions. Extensive quantitative reverse transcription-polymerase chain reaction experiments were performed to evaluate the expressions of genes related to osteotropic bone metastasis of PCa. On the nanoclay scaffolds, the MSCs differentiated to mature osteoblasts and epithelial to mesenchymal transition was inhibited whereas mesenchymal to epithelial transition was enhanced, as also the hypoxia increased angiogenesis, and finally, PCa cells initiated osteoblastic lesion. Further, the SC technique has significant effects on expression of key metastasis-related genes. Therefore, the SC-based tumour model can be applied to recapitulate more consistent osteotropic cancer cell behavior in understanding tumour biology. This model also can be implemented for drug screening to target colonization stage of PCa cells in the bone microenvironment.

PSA-PSMA profiles and their impact on sera PSA levels and angiogenic activity in hyperplasia and human prostate cancer.

AIM: The relevance of prostate specific antigen (PSA)-prostate specific membrane antigen (PSMA) profiles in pathologic prostate (hyperplasia and cancer) has not been fully understood. The aim of this study is to investigate the impact of PSA-PSMA profiles on sera PSA levels and angiogenic activity in benign prostate hyperplasia (BPH) and prostate carcinoma (PC). PATIENTS AND METHODS: The study has been carried out in 6 normal prostate (NP), 29 BPH and 33 PC with dominant Gleason grade>8. Immunohistochemical analysis has been performed. Monoclonal antibodies 3E6 and ER-PR8 have been used to assess PSMA and PSA expression respectively. The evaluation of angiogenesis has been made by CD34 immune marker. Serum levels of PSA have been assayed by Immulite autoanalyser. RESULTS: The study of each protein separately among sera PSA levels showed that PSMA expression and angiogenic activity have the highest intensity in PC patients with serum PSA levels>20 ng/mL. Nevertheless, the lowest tissue PSA expression was found in PC patients with this latter sera PSA group. The most relevant results showed that in PC patients (PSA+, PSMA+) and (PSA-, PSMA+) profile were found to be inversely related to sera PSA levels. In PC patients, a high immunoexpression of (PSA+, PSMA+) profile has detected in the sera PSA group>20 ng/mL; whereas a high immunoexpression of (PSA-, PSMA+) profile was detected in the sera PSA group between 0 and 4 ng/mL. The highest angiogenic activity was found in PC patients with (PSA+, PSMA+) profile. CONCLUSIONS: Our findings clearly have supported the feasibility of PSA-PSMA profiles to improve in vivo diagnostic and therapeutic approaches in prostate cancer patients.

Identification of ML-9 as a lysosomotropic agent targeting autophagy and cell death.

The growing number of studies suggested that inhibition of autophagy enhances the efficacy of Akt kinase inhibitors in cancer therapy. Here, we provide evidence that ML-9, a widely used inhibitor of Akt kinase, myosin light-chain kinase (MLCK) and stromal interaction molecule 1 (STIM1), represents the 'two-in-one' compound that stimulates autophagosome formation (by downregulating Akt/mammalian target of rapamycin (mTOR) pathway) and inhibits their degradation (by acting like a lysosomotropic agent and increasing lysosomal pH). We show that ML-9 as a monotherapy effectively induces prostate cancer cell death associated with the accumulation of autophagic vacuoles. Further, ML-9 enhances the anticancer activity of docetaxel, suggesting its potential application as an adjuvant to existing anticancer chemotherapy. Altogether, our results revealed the complex effect of ML-9 on autophagy and indentified ML-9 as an attractive tool for targeting autophagy in cancer therapy through dual inhibition of both the Akt pathway and the autophagy.

Chronic administration of green tea extract to TRAMP mice induces the collapse of Golgi apparatus in prostate secretory cells and results in alterations of protein post-translational processing.

Considering its long latency, prostate cancer (PCa) represents an ideal target for chemoprevention strategies. Green tea extract (GTE) has been proved to be one of the most promising natural substances capable of inhibiting PCa progression in animal models (transgenic adenocarcinoma of mouse prostate), as well as in humans. However, the cellular targets of the GTE action are mostly unknown. The main objective of this work was to investigate whether the endoplasmic reticulum (ER) and the Golgi apparatus (GA), known to be actively involved in sensing stress stimuli and initiating and propagating cell death signalling, may represent the subcellular targets of GTE action. To this end, 42 TRAMP mice were divided into four experimental groups: groups II and IV, received GTE in tap water (0.3 g/100 ml solution) starting at 8 weeks of age and up to the time of sacrifice. Groups I and III were respective age-matched water-fed controls. The animals were sacrificed after 4 weeks (groups I and II) or 40 weeks of treatment (groups II and IV). We also treated TRAMP-C2 cells with GTE (20 µg/ml for 7 days) to check the expression profile of clusterin (CLU), a protein involved in prostate tumourigenesis, extensively processed through ER-GA before being secreted through the plasma membrane. In vivo we found that chronic administration of GTE in TRAMP mice results in collapse of ER and GA in prostate epithelial cells. Consistently, in vitro we found that the mature, fully processed form of CLU, sCLU, is strongly reduced by GTE treatment in TRAMP-C2 cells. Taking into account the sCLU biogenesis dependence on the ER-GA integrity and the proposed anti-apoptotic role of sCLU, the possibility for GTE to counteract PCa progression by interfering with sCLU biogenesis is suggested.

Licorice and licochalcone-A induce autophagy in LNCaP prostate cancer cells by suppression of Bcl-2 expression and the mTOR pathway.

Licorice is a common Chinese medicinal herb with antitumor activity. Some components in licorice root have been shown to induce cell cycle arrest or apoptosis in cancer cells. This paper demonstrates for the first time that licorice Glycyrrhiza glabra and its component licochalcone-A (LA) can induce autophagy in addition to apoptosis in human LNCaP prostate cancer cells. Exposure of cells to licorice or LA resulted in several confirmed characteristics of autophagy, including the appearance of autophagic vacuoles revealed by monodansylcadaverine (MDC) staining, formation of acidic vesicular organelles (AVOs), and autophagosome membrane association of microtubule-associated protein 1 light chain 3 (LC3) characterized by cleavage of LC3 and its punctuate redistribution, as well as ultrastructural observation of autophagic vacuoles by transmission electron microscopy. Autophagy induction was accompanied by down-regulation of Bcl-2 and inhibition of the mammalian target of rapamycin (mTOR) pathway. In summary, licorice can induce caspase-dependent and autophagy-related cell death in LNCaP cells.

[Artesunate induces prostate cancer cell line PC-3 differentiation and cell cycle arrest].

OBJECTIVE: To explore the effect of artesunate (ART) on cell differentiation and cell cycle distribution of the prostate cancer cell line PC-3 in vitro. METHODS: PC-3 cells were cultivated with ART from logarithmic growth phase. After 48-hour treatment, the cell cycles were detected by flow cytometry (FCM), and enzyme linked immunosorbent assay was used to detect the level of prostate specific antigen (PSA) in cell culture supernatant. The change of cellular morphology was observed under a transmission electron microscope (TEM). RESULTS: In comparison with the blank control group, the rate of G(0)/G(1) plus S stages of PC-3 cells was significantly decreased in the high-dose ART group. The PC-3 cell was arrested in G(2)/M by ART. The rates of G(2)/M of the high-dose ART group and the medium-dose ART group were obviously higher than those of the blank control group and the cisplatin group (P<0.05). The levels of PSA in the three ART groups were significantly lower than that of the normal control group (P<0.05, P<0.01). In the ART groups, TEM showed that some vacuoles appeared in endochylema, cell polarity was enhanced, cell nucleus leaned to one side of the cell, and microvilli increased on the other side of the cell. CONCLUSION: ART can induce PC-3 cell cycle arrest and differentiation in vitro.

Utilidad de la expresión de Ki67 en las biopsias preoperatorias para predecir la recidiva bioquímica del cáncer de próstata después de la prostatectomía radical / The usefulness of Ki67 expression in the biopsy specimens, to predict the biochemical progresion of the prostate cancer after radical prostatectomy

OBJETIVO: Evaluar la utilidad de la expresión de Ki67 de las biopsias diagnósticas preoperatorias, para predecir la recidiva bioquímica del cáncer de próstata después de la prostatectomía radical. MATERIAL Y MÉTODOS: Analizamos la expresión de Ki67 en las biopsias ecodirigidas de 103 pacientes a los que se les practicó prostatectomía radical. El tiempo medio de seguimiento es de 3,4 años (1,3-8,8 años). Correlacionamos la recidiva bioquímica con los factores pronósticos clásicos como el PSA (>10/=7/3%/3%/3%/10/=7/<7) y clasificación pT (pT3/pT0-2), para predecir la progresión bioquímica del cáncer de próstata después de la prostatectomía radical

OBJETIVE: To evaluate the usefulness of Ki67 expression in the biopsy specimens, to predict the biochemical progression of the prostate cancer after radical prostatectomy. MATERIAL AND METHODS: We analyse the Ki67 expression in the biopsy specimens of 103 patients treated with radical prostatectomy. The mean follow up is 3.4 years (1.3-8.8 years). We correlate the biochemical progression with traditional prognostic factors as the PSA (>10/=7/3%/3%/3%/10/=7/<7) and pT ification (pT3/pT0-2), to predict the biochemical progression of the prostate cancer after radical prostatectomy

Differential effects of prolactin on rat dorsolateral prostate and R3327 prostatic tumor sublines.

Many investigators have reported effects of the pituitary hormone, prolactin, on the physiology and biochemistry of the rat prostate gland, particularly the lateral or dorsolateral lobe. The Dunning R3327H is a transplantable rat prostatic adenocarcinoma derived from a spontaneous tumor of the Copenhagen rat dorsolateral prostate. This study describes and compares morphological and physiological effects of prolactin on rat dorsolateral prostate and two sublines of the Dunning tumor. Ectopic pituitary grafts were used to induce chronic hyperprolactinemia in castrated rats receiving androgen supplement to provide a relatively controlled hormonal environment in which the effects of prolactin were maximally and consistently observed. Gravimetric and biochemical analyses, as well as ultrastructural study, provided evidence of prolactin's stimulatory effect on dorsolateral prostate growth and secretory activity. Hyperprolactinemia stimulated the growth of the well-differentiated, androgen-dependent R3327/3219 tumor subline with an increase in weight, volume and the total content of DNA, protein and zinc. There were no changes in tumor morphology. In contrast, the anaplastic androgen-independent R3327/150 tumor subline did not respond to graft-induced hyperprolactinemia. This differential response of the two R3327 tumor sublines attests to the complexity of prolactin's effects on prostatic tissue and to the extent of the deterioration of endocrine control that often accompanies tumor progression. Prolactin binding in the R3327 sublines was studied using immunohistochemical staining and radioligand assay, but produced complex results which raise questions about the discrepancy between hormone binding and biological action of prolactin in prostatic tissues.