Focal therapy in prostate cancer: the current situation

Liposomal curcumin and its application in cancer

Curcumin (CUR) is a yellow polyphenolic compound derived from the plant turmeric. It is widely used to treat many types of diseases, including cancers such as those of lung, cervices, prostate, breast, bone and liver. However, its effectiveness has been limited due to poor aqueous solubility, low bioavailability and rapid metabolism and systemic elimination. To solve these problems, researchers have tried to explore novel drug delivery systems such as liposomes, solid dispersion, microemulsion, micelles, nanogels and dendrimers. Among these, liposomes have been the most extensively studied. Liposomal CUR formulation has greater growth inhibitory and pro-apoptotic effects on cancer cells. This review mainly focuses on the preparation of liposomes containing CUR and its use in cancer therapy.

Targeting of NHERF1 through RNA interference inhibits the proliferation and migration of metastatic prostate cancer cells

The present study aimed to investigate the effects of Na+/H+ exchanger regulatory factor 1 (NHERF1) gene knockdown, using short-hairpin RNA (shRNA), on the malignant behaviors of prostate cancer cells. A pSuper.puro NHERF1 shRNA vector was transfected into PC-3M prostate cancer cells using Lipofectamine 2000. Stable cell lines were obtained and NHERF1 knockdown was verified through western blot analysis. MTT assays were then used to measure PC-3M cell proliferation; in addition, cell migration was assessed using a wound healing assay. Flow cytometry was employed in order to determine the effects of NHERF1 knockdown on apoptosis. Expression levels of apoptotic pathway proteins B cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein were then determined by western blot analysis. The results demonstrated that shRNA knockdown of NHERF1 significantly suppressed the proliferation of PC-3M cells by >50%. In addition, knockdown of NHERF1 significantly inhibited the migration of PC-3M cells. PC-3M cells harboring NHERF1 shRNA exhibited significantly increased apoptosis, with an ~4-fold increase compared with that of the parental PC-3M cells and cells transfected with an empty vector. Furthermore, the results revealed that knockdown of NHERF1 reduced the protein expression of Bcl-2, although the expression of Bax was unaltered. In conclusion, NHERF1 knockdown using shRNA inhibited the proliferation and migration of PC-3M cells and promoted apoptosis, highlighting the role of NHERF1 in prostate cancer progression.

Upregulation of ULK1 expression in PC-3 cells following tumor protein P53 transfection by sonoporation

The aim of the present study was to investigate whether ultrasound combined with microbubbles was able to enhance liposome-mediated transfection of genes into human prostate cancer cells, and to examine the association between autophagy and tumor protein P53 (P53). An MTT assay was used to evaluate cell viability, while flow cytometry and fluorescence microscopy were used to measure gene transfection efficiency. Autophagy was observed using transmission electron microscopy. Reverse transcription-polymerase chain reaction (RT-PCR) and western blot analysis were used to assess the expression of autophagy-associated genes. The results of the present study revealed that cell viability was significantly reduced following successfully enhanced transfection of P53 by ultrasound combined with microbubbles. In addition, serine/threonine-protein kinase ULK1 levels were simultaneously upregulated. Castration-resistant prostate cancer is difficult to treat and is investigated in the present study. P53 has a significant role in a number of key biological functions, including DNA repair, apoptosis, cell cycle, autophagy, senescence and angiogenesis. Prior to the present study, to the best of our knowledge, increased transfection efficiency and reduced side effects have been difficult to achieve. Ultrasound is considered to be a 'gentle' technique that may be able to achieve increased transfection efficiency and reduced side effects. The results of the present study highlight a potential novel therapeutic strategy for the treatment of prostate cancer.

Upregulation of Beclin-1 expression in DU-145 cells following low-frequency ultrasound irradiation combined with microbubbles

Castration-resistant prostate cancer (PCa) is difficult to treat. Autophagy, which is an evolutionarily conserved mechanism, plays an important role in cancer development. The balance between cell death and survival in different stages varies in cancer development. The role of autophagy in PCa development has not yet been fully elucidated. Ultrasound may be of value in the treatment of PCa. The aim of the present study was to investigate the association between autophagy and ultrasound combined with microbubbles. The MTT assay was used to evaluate cell viability. Autophagy was observed by transmission electron microscopy. Reverse transcription-polymerase chain reaction and western blot analysis were used to assess the expression of autophagy-related genes. The results revealed that cell viability was significantly reduced by ultrasound combined with microbubbles in DU145 PCa cells. The present study demonstrated that ultrasound combined with microbubbles induced autophagy and autophagy-related DU-145 cell death. Notably, these findings highlighted additional mechanisms that suggest the potential of ultrasound-modulated autophagy as a novel therapeutic strategy for PCa.