Rho-Associated Protein Kinase (ROCK) Promotes Proliferation and Migration of PC-3 and DU145 Prostate Cancer Cells by Targeting LIM Kinase 1 (LIMK1) and Matrix Metalloproteinase-2 (MMP-2)

Promoting Polarization and Differentiation of Primary Human Salivary Gland Stem/Progenitor Cells in Protease-Degradable Hydrogels via ROCK Inhibition

Toward the goal of in vitro engineering of functional salivary gland tissues, we cultured primary human salivary stem/progenitor cells (hS/PCs) in hyaluronic acid-based matrices with varying percentages of proteolytically degradable crosslinks in the presence of Rho kinase (ROCK) inhibitor. Single cells encapsulated in the hydrogel grew into organized multicellular structures by day 15, and over 60% of the structures developed in the nondegradable and 50% degradable hydrogels contained a central lumen. Importantly, ROCK inhibition led to the establishment of multicellular structures that were correctly polarized, as evidenced by apical localization of a Golgi marker GM130, apical/lateral localization of tight junction protein zonula occludens-1 (ZO-1), and basal localization of integrin β1 and basement membrane proteins laminin α1 and collagen IV. Cultures maintained in 50% degradable gels with ROCK inhibition exhibited an increased expression of acinar markers aquaporin 5 (AQP5, AQP5) and sodium-potassium-chloride cotransporter 1 (SLC12A2, NKCC1) at the transcript and the protein levels, respectively, as compared to those without ROCK inhibition. Upon stimulation with isoproterenol, α-amylase secretion into the lumen was observed. Particle-tracking microrheology was employed to analyze the stiffness of cells using mitochondria as the passive tracer particles. Our results indicated that cells grown in 100% degradable gels were stiffer than those maintained in nondegradable gels, and cells cultured with the ROCK inhibitor were softer than those maintained without the inhibitor. We conclude that reducing cellular contractility via ROCK inhibition while retaining some degree of matrix confinement promotes the establishment of multicellular structures containing pro-acinar cells with correct apicobasal polarization.

Identification of LIMK1 as a biomarker in clear cell renal cell carcinoma: from data mining to validation

PURPOSE

Clear cell renal cell carcinoma (ccRCC) is one of the most common types of renal cancer. LIM kinase 1 (LIMK1) reportedly plays an important role in tumorigenesis. However, the involvement of LIMK1 in the progression of ccRCC remains ambiguous.

METHODS

Based on the TCGA and CPTAC databases, the expression of LIMK1 in ccRCC was evaluated. In the TCGA-ccRCC cohort, the relationships between LIMK1 and immune cell infiltration as well as immune checkpoints were assessed. The high expression of LIMK1 in ccRCC was verified by qRT-PCR in four RCC cell lines. Immunohistochemistry was used to evaluate the expression of LIMK1 in clinical samples. The association between LIMK1 expression and survival prognosis was explored via Kaplan-Meier survival curve in the TCGA-ccRCC and local cohorts. The effects of LIMK1 knockdown on the proliferation, migration, and invasion abilities of RCC cells were evaluated via colony, CCK-8, wound healing, and Transwell assays.

RESULTS

Elevated expression level of LIMK1 was found in the TCGA-ccRCC cohort and was confirmed in RCC cell lines and clinical samples. Up-regulation of LIMK1 was found to be correlated with poor prognosis in TCGA-ccRCC and external cohorts. In addition, high-LIMK1 was associated with clinicopathological stage, immune cell infiltration and immune checkpoint in ccRCC. Importantly, knockdown of LIMK1 diminished the capability of proliferation, migration, and invasion in RCC cells.

CONCLUSION

LIMK1 may serve as a promising diagnostic and prognostic biomarker of ccRCC.

Promoting Polarization and Differentiation of Primary Human Salivary Gland Stem/Progenitor Cells in Protease-Degradable Hydrogels via ROCK Inhibition

Towards the goal of in vitro engineering of functional salivary gland tissues, we cultured primary human salivary stem/progenitor cells (hS/PCs) in hyaluronic acid-based matrices with varying percentages of proteolytically degradable crosslinks in the presence of Rho kinase (ROCK) inhibitor. Single cells encapsulated in the hydrogel grew into organized multicellular structures by day 15, and over 60% of the structures developed in the non-degradable and 50% degradable hydrogels contained a central lumen. Importantly, ROCK inhibition led to the establishment of multicellular structures that were correctly polarized, as evidenced by apical localization of a Golgi marker GM130, apical/lateral localization of tight junction protein zonula occludens-1 (ZO-1), and basal localization of integrin β1 and basement membrane proteins laminin α1 and collagen IV. Cultures maintained in 50% degradable gels with ROCK inhibition exhibited an increased expression of acinar markers AQP5 and SLC12A2 (at the transcript level) and AQP5 and NKCC1 (at the protein level) as compared to those without ROCK inhibition. Upon stimulation with isoproterenol, α-amylase secretion into the lumen was observed. Particle-tracking microrheology was employed to analyze the stiffness of cells using mitochondria as the passive tracer particles. Our results indicated that cells grown in 100% degradable gels were stiffer than those maintained in non-degradable gels, and cells cultured with the ROCK inhibitor were softer than those maintained without the inhibitor. We conclude that reducing cellular contractility via ROCK inhibition while retaining some degree of matrix confinement promotes the establishment of multicellular structures containing pro-acinar cells with correct apicobasal polarization.

Y-27632 targeting ROCK1&2 modulates cell growth, fibrosis and epithelial-mesenchymal transition in hyperplastic prostate by inhibiting β-catenin pathway

Benign prostatic hyperplasia (BPH) is a prevalent condition affecting the male urinary system, with its molecular mechanisms of pathogenesis remaining unclear. Y-27632, a non-isoform-selective Rho kinase inhibitor, has shown therapeutic potential in various diseases but its effects on static factors and fibrosis in BPH remain unexplored. This study investigated human prostate tissues, human prostate cell lines, and BPH rat model using immunofluorescence, flow cytometry, quantitative reverse transcription polymerase chain reaction, western blotting, and cell counting kit-8. ROCK1 and ROCK2 were significantly up-regulated in BPH tissues, correlating with clinical parameters. Y-27632 targeted the inhibition of ROCK1 & ROCK2 expression and inhibited cell proliferation, fibrosis, epithelial-mesenchymal transition (EMT), while induced cell apoptosis in a dose-dependent manner. Moreover, knockdown of either ROCK isoform inhibited fibrosis and EMT, induced apoptosis, while ROCK overexpression had the opposite effects. ROCK downregulation inhibited the β-catenin signaling pathway (such as C-MYC, Snail and Survivin) and decreased β-catenin protein stability, while inhibiting TGF-β/Smad2/3 signaling. At the in vivo level, Y-27632 reversed prostatic hyperplasia and fibrosis in BPH model rats to some extent. Our study sheds light on the therapeutic potential of Y-27632 in regulating prostate cell growth, fibrosis and EMT, and demonstrates for the first time the regulatory effect of ROCK isoforms on prostate cells, providing the basis for future research of ROCK isoform-selective inhibitors.

Role of miRNA‑122 in cancer (Review)

MicroRNAs (miRNAs) are small non‑coding RNAs that serve key roles in cell proliferation, migration, invasion and apoptosis by regulating gene expression. In malignant tumors, miRNA‑122 serves either as a tumor suppressor or oncogene, influencing tumor progression via downstream gene targeting. However, the precise role of miRNA‑122 in cancer remains unclear. miRNA‑122 is a potential biomarker and modulator of radiotherapy and chemotherapy. The present review aimed to summarize the roles of miRNA‑122 in cancer, its potential as a biomarker for diagnosis and prognosis and its implications in cancer therapy, including radiotherapy and chemotherapy, alongside strategies for systemic delivery.

Decoding the tumour-modulatory roles of LIMK2

LIM domains kinase 2 (LIMK2) is a 72 kDa protein that regulates actin and cytoskeleton reorganization. Once phosphorylated by its upstream activator (ROCK1), LIMK2 can phosphorylate cofilin to inactivate it. This relieves the levering stress on actin and allows polymerization to occur. Actin rearrangement is essential in regulating cell cycle progression, apoptosis, and migration. Dysregulation of the ROCK1/LIMK2/cofilin pathway has been reported to link to the development of various solid cancers such as breast, lung, and prostate cancer and liquid cancer like leukemia. This review aims to assess the findings from multiple reported in vitro, in vivo, and clinical studies on the potential tumour-regulatory role of LIMK2 in different human cancers. The findings of the selected literature unraveled that activated AKT, EGF, and TGF-β pathways can upregulate the activities of the ROCK1/LIMK2/cofilin pathway. Besides cofilin, LIMK2 can modulate the cellular levels of other proteins, such as TPPP1, to promote microtubule polymerization. The tumour suppressor protein p53 can transactivate LIMK2b, a splice variant of LIMK2, to induce cell cycle arrest and allow DNA repair to occur before the cell enters the next phase of the cell cycle. Additionally, several non-coding RNAs, such as miR-135a and miR-939-5p, could also epigenetically regulate the expression of LIMK2. Since the expression of LIMK2 is dysregulated in several human cancers, measuring the tissue expression of LIMK2 could potentially help diagnose cancer and predict patient prognosis. As LIMK2 could play tumour-promoting and tumour-inhibiting roles in cancer development, more investigation should be conducted to carefully evaluate whether introducing a LIMK2 inhibitor in cancer patients could slow cancer progression without posing clinical harms.

Dasabuvir suppresses esophageal squamous cell carcinoma growth in vitro and in vivo through targeting ROCK1

Esophageal squamous cell carcinoma (ESCC) is an upper gastrointestinal cancer with high morbidity and mortality. New strategies are urgently needed to prolong patients' survival. Through screening FDA-approved drugs, we found dasabuvir, a drug approved for hepatitis C virus (HCV) treatment, suppressed ESCC proliferation. Dasabuvir could inhibit the growth of ESCC cells in a time and dose-dependent manner and arrested cell cycle at the G0/G1 phase. The antitumor activity was further validated in vivo using patient-derived xenograft tumor models. In terms of mechanism, we unveil that dasabuvir is a Rho-associated protein kinase 1 (ROCK1) inhibitor. Dasabuvir can bind to ROCK1 and suppress its kinase activity, thus downregulating the phosphorylation of ERK1/2 by ROCK1 and the expression of cyclin-dependent kinase 4 (CDK4) and cyclin D1. These results provide evidence that dasabuvir suppresses ESCC growth in vivo and in vitro through blocking ROCK1/ERK signaling pathway.

Activity of ROCKII not ROCKI promotes pulmonary metastasis of melanoma cells via modulating Smad2/3-MMP9 and FAK-Src-VEGF signalling

Rho-associated coiled-coil kinase (ROCK) inhibition decreases tumourogenic growth, proliferation and angiogenesis. Multifaceted evidences are there about the role of ROCK in cancer progression, but isoform specific analysis in secondary pulmonary melanoma is still unaddressed. This study explored the operating function of ROCK in the metastasis of B16F10 mice melanoma cell line. Inhibition by KD-025 indicated dual wielding role of ROCKII as it is associated with the regulation of MMP9 activity responsible for extra-cellular matrix (ECM) degradation as well as angiogenic invasion as an effect of Src-FAK-STAT3 interaction dependent VEGF switching. We found the assisting role of ROCKII, not ROCKI in nuclear localization of Smads that effectively increased MMP9 expression and activity (p < 0.01). This cleaved the protein components of ECM thereby played a crucial role in tissue remodeling at secondary site during establishment of metastatic tumour. ROCKII phosphorylation at Ser¹³⁶⁶ as an activation of the same was imprinted essential for oncogenic molecular bagatelle leading to histo-architectural change of pulmonary tissue with extracellular matrix degradation as a consequence of invasion. Direct correlation of pROCKIISer¹³⁶⁶ with MMP9 as well as VEGF expression in vivo studies cue to demonstrate the importance of pROCKIISer¹³⁶⁶ inhibition in the context of angiogenesis, and metastasis suggesting ROCKII signaling as a possible target for the treatment of secondary lung cancer specially in metastatic melanoma.

The redox modulatory effects of SP/NK1R system: Implications for oxidative stress-associated disorders

Oxidative stress which refers to redox imbalance with increased generation of reactive oxygen species (ROS) has been associated with the pathophysiology of diverse disease conditions. Recently, a close, yet not fully understood, relation between oxidative stress and neuropeptides, in particular, substance P (SP), has been reported in certain conditions. SP has been shown to affect the cellular redox environment through activation of neurokinin-1receptor (NK1R). It seems that SP/NK1R system and oxidative stress can act either synergistically or antagonistically in a context-dependent manner, thereby, influencing the pathology of various clinical disorders either destructively or protectively. Importantly, the interactions between oxidative stress and SP/NK1R system can be pharmacologically targeted. Therefore, a better understanding of the redox modulatory properties of SP/NK1R signaling will pave the way for identifying new therapeutic possibilities for attenuating oxidative stress-mediated damage. Towards this end, we performed a comprehensive search through PubMed/Medline and Scopus databases and discussed all related existing literature regarding the interplay between oxidative stress and SP/NK1R system as well as their implication in various clinical disorders, to provide a clear view and hence better management of oxidative damage.

The Role of LIM Kinase in the Male Urogenital System

The LIM kinases (LIMK1 and LIMK2), known as downstream effectors, and the Rho-associated protein kinase (ROCK), a regulator of actin dynamics, have effects on a diverse set of cellular functions. The LIM kinases are involved in the function of the male urogenital system by smooth muscle contraction via phosphorylation of cofilin and subsequent actin cytoskeleton reorganization. Although LIMK1 and LIMK2 share sequence similarities as serine protein kinases, different tissue distribution patterns and distinct localization during cell cycle progression suggest other biological functions for each kinase. During meiosis and mitosis, the LIMK1/2–cofilin signaling facilitates the orchestrated chromatin remodeling between gametogenesis and the actin cytoskeleton. A splicing variant of the LIMK2 transcript was expressed only in the testis. Moreover, positive signals with LIMK2-specific antibodies were detected mainly in the nucleus of the differentiated stages of germ cells, such as spermatocytes and early round spermatids. LIMK2 plays a vital role in proper spermatogenesis, such as meiotic processes of spermatogenesis after puberty. On the other hand, the literature evidence revealed that a reduction in LIMK1 expression enhanced the inhibitory effects of a ROCK inhibitor on the smooth muscle contraction of the human prostate. LIMK1 may have a role in urethral obstruction and bladder outlet obstruction in men with benign prostatic hyperplasia. Moreover, LIMK1 expression was reduced in urethral stricture. The reduced LIMK1 expression caused the impaired proliferation and migration of urethral fibroblasts. In addition, the activated LIMK2–cofilin pathway contributes to cavernosal fibrosis after cavernosal nerve injury. Recent evidence demonstrated that short-term inhibition of LIMK2 from the immediate post-injury period prevented cavernosal fibrosis and improved erectile function in a rat model of cavernosal nerve injury. Furthermore, chronic inhibition of the LIMK2–cofilin pathway significantly restrained the cavernosal veno-occlusive dysfunction, the primary pathophysiologic mechanism of post-prostatectomy erectile dysfunction through suppressing fibrosis in the corpus cavernosum. In conclusion, the LIM kinases–cofilin pathway appears to play a role in the function of the male urogenital system through actin cytoskeleton reorganization and contributes to the pathogenesis of several urogenital diseases. Therefore, LIM kinases may be a potential treatment target in urogenital disorder.

MYO1B enhances colorectal cancer metastasis by promoting the F-actin rearrangement and focal adhesion assembly via RhoA/ROCK/FAK signaling

Background

Colorectal cancer (CRC) has a high worldwide incidence and mortality. Tumor metastasis is one of the primary reasons for the poor prognosis of CRC patients. However, the mechanism underlying CRC metastasis is still unclear. Myosin 1B (MYO1B) is important for cell migration and motility and is part of the myosin superfamily that contains various myosins. Studies of prostate, cervical, and head and neck cancer have revealed preliminary findings concerning the effect of MYO1B on tumor metastasis. However, the role of MYO1B in CRC metastasis, as well as its underlying mechanism, remains unknown.

Methods

Quantitative real-time PCR and immunohistochemical staining methods were used to analyze the expression of MYO1B in human CRC and normal mucosa tissues. Lentivirus vector-based MYO1B oligonucleotides and short hairpin RNA (shRNA) were used to examine the functional relevance of MYO1B in CRC cells. Co-immunoprecipitation, western blotting, and immunofluorescence assays were used to investigate the underlying mechanism of MYO1B-mediated cell migration.

Results

The expression of MYO1B was increased in most CRC tissues and was positively associated with a greater risk of tumor metastasis and poor prognosis for patients. MYO1B was significantly associated with the migration and invasion properties of CRC cells in vitro and in vivo. MYO1B promoted F-actin rearrangement through the ROCK2/LIMK/Cofilin axis by enhancing the activation of RhoA. MYO1B also promoted the assembly of focal adhesions by targeting RhoA.

Conclusions

MYO1B plays a vital role in CRC metastasis by promoting the activation of RhoA. MYO1B may not only be a valid biomarker for predicting the risk of metastasis and poor prognosis in CRC but may also be a potential therapeutic target for patients with a high risk of tumor metastasis.

AS1 expression in prostate cancer and its effects on proliferation and invasion of prostate cancer cells

This paper aimed at investigating AS1 expression in prostate cancer (PCa) and its effects on the proliferation and invasion of prostate cancer cells (PCCs). The prostate tissues and the matched adjacent normal prostate tissues excised and preserved during radical prostatectomy in our hospital were collected. The LncRNA NCK1-AS1 expression was detected. PCa patients were followed up for three years to analyze their prognosis. The correlation of LncRNA NCK1-AS1 expression with clinicopathological features was analyzed. Human normal prostate cells and human PCCs were selected, in which LncRNA NCK1-AS1 expression was tested to screen and then transfect the cells. Cell proliferation, invasion and migration were detected. Cell cycles and apoptosis were analyzed. Compared with the adjacent normal tissues, LncRNA NCK1-AS1 was highly expressed in the prostate cancer tissues. Its expression was remarkably different in those with different stages of TNM and with lymphatic metastasis or not. The prognosis of patients with high LncRNA NCK1-AS1 expression was remarkably poorer than that of those with low expression. Compared with the human normal prostate cells, LncRNA NCK1-AS1 expression in the human PCCs remarkably rose, with the greatest difference in 22Rv1 cells. Compared with the Blank group, cell proliferation and the number of plate cloned cells remarkably reduced in the sh-NCK1-AS1 group. Additionally, in this group, the number of invasive and migratory cells remarkably reduced; the expression of invasion-related protein E-cadherin remarkably rose but that of MMP-2 remarkably reduced; cell cycles were arrested and the expression of cycle-related proteins (CDK4, CDK6, cyclin D1) remarkably reduced; the apoptotic rate and the expression of apoptosis-related protein Bax remarkably rose. LncRNA NCK1-AS1 is highly expressed in PCa, so its down-regulation can inhibit PCCs from proliferating and reduce the number of invasive cells.

FOXD3‑AS1/miR‑128‑3p/LIMK1 axis regulates cervical cancer progression

Long non‑coding RNA forkhead box D3 antisense RNA 1 (FOXD3‑AS1) functions as an oncogenic regulator in several types of cancer, including breast cancer, glioma and cervical cancer. However, the effects and mechanisms underlying FOXD3‑AS1 in cervical cancer (CC) are not completely understood. The present study aimed to investigate the biological functions and potential molecular mechanisms underlying FOXD3‑AS1 in CC progression. Reverse transcription‑quantitative PCR was performed to detect FOXD3‑AS1, microRNA (miR)‑128‑3p and LIM domain kinase 1 (LIMK1) expression levels in CC tissues and cells. Immunohistochemical staining and western blotting were conducted to assess LIMK1 protein expression levels in CC tissues and cells, respectively. Cell Counting Kit‑8 and BrdU assays were used to determine the role of FOXD3‑AS1 in regulating cell proliferation. CC cell migration and invasion were assessed by performing Transwell assays. Dual‑luciferase reporter assays were conducted to verify the binding between miR‑128‑3p and FOXD3‑AS1. FOXD3‑AS1 expression was significantly increased in CC tissues and cell lines compared with adjacent healthy tissues and normal cervical epithelial cells, respectively. High FOXD3‑AS1 expression was significantly associated with poor differentiation of tumor tissues, increased tumor size and positive lymph node metastasis. FOXD3‑AS1 overexpression significantly increased CC cell proliferation, migration and invasion compared with the negative control (NC) group, whereas FOXD3‑AS1 knockdown resulted in the opposite effects compared with the small interfering RNA‑NC group. Moreover, the results demonstrated that FOXD3‑AS1 targeted and negatively regulated miR‑128‑3p, which indirectly upregulated LIMK1 expression. Therefore, the present study demonstrated that FOXD3‑AS1 upregulated LIMK1 expression via competitively sponging miR‑128‑3p in CC cells, promoting CC progression.

The miR-136-5p/ROCK1 axis suppresses invasion and migration, and enhances cisplatin sensitivity in head and neck cancer cells

Laryngeal squamous cell carcinoma (LSCC) and hypopharyngeal squamous cell carcinoma (HPSCC) are two types of head and neck cancers with high incidence rates and relatively poor prognoses. The aim of the present study was to determine the effects of microRNA (miR/miRNA)-136-5p and its downstream target, Rho-associated coiled-coil containing protein kinase 1 (ROCK1), on LSCC and HPSCC progression and cisplatin sensitivity. The miRNA and protein expression levels in head and neck cancer cell lines were evaluated using reverse transcription-quantitative PCR and western blotting, respectively. MTT, wound healing assays, transwell assays and flow cytometry analysis were performed to measure cell properties. The binding between miR-136-5p and ROCK1 was detected using a dual-luciferase reporter assay. Autophagy double-labeled adenoviral infection assays were used to assess cell autophagy. The results showed that miR-136-5p was expressed in LSCC and HPSCC cells. Functional experiments showed that the expression of miR-136-5p in LSCC and HPSCC cells was negatively correlated with cell viability, invasion and migration. Additionally, miR-136-5p overexpression inhibited epithelial-mesenchymal transition, whereas miR-136-5p knockdown had the opposite effect. Dual-luciferase reporter assays confirmed the targeting relationship between miR-136-5p and ROCK1. miR-136-5p overexpression increased the cisplatin sensitivity of LSCC and HPSCC cells by reducing cell viability, as well as promoting cell apoptosis and autophagy. miR-136-5p overexpression decreased the expression levels of its downstream target ROCK1 and attenuated activity of the Akt/mTOR signaling pathway in cisplatin-treated LSCC and HPSCC cells. Conversely, miR-136-5p knockdown increased ROCK1 levels and decreased cisplatin sensitivity of the LSCC and HPSCC cells by increasing cell viability and inhibiting cell apoptosis, which was reversed by ROCK1 inhibition using the ROCK1 inhibitor, Y27632. Taken together, the results showed that the miR-136-5p/ROCK1 axis inhibits cell invasion and migration, and increases the sensitivity of LSCC and HPSCC cells to cisplatin.

Advances in Targeting Cancer-Associated Genes by Designed siRNA in Prostate Cancer

Short interfering RNAs (siRNAs) have provided novel insights into the field of cancer treatment in light of their ability to specifically target and silence cancer-associated genes. In recent years, numerous studies focus on determining genes that actively participate in tumor formation, invasion, and metastasis in order to establish new targets for cancer treatment. In spite of great advances in designing various siRNAs with diverse targets, efficient delivery of siRNAs to cancer cells is still the main challenge in siRNA-mediated cancer treatment. Recent advancements in the field of nanotechnology and nanomedicine hold great promise to meet this challenge. This review focuses on recent findings in cancer-associated genes and the application of siRNAs to successfully silence them in prostate cancer, as well as recent progress for effectual delivery of siRNAs to cancer cells.

Phosphoinositide-dependent Kinase-1 (PDPK1) regulates serum/glucocorticoid-regulated Kinase 3 (SGK3) for prostate cancer cell survival

Prostate cancer (PCa) is the most common malignancy and is the second leading cause of cancer among men globally. Using a kinome-wide lentiviral small-hairpin RNA (shRNA) library screen, we identified phosphoinositide-dependent kinase-1 (PDPK1) as a potential mediator of cell survival in PCa cells. We showed that knock-down of endogenous human PDPK1 induced significant tumour-specific cell death in PCa cells (DU145 and PC3) but not in the normal prostate epithelial cells (RWPE-1). Further analyses revealed that PDPK1 mediates cancer cell survival predominantly via activation of serum/glucocorticoid-regulated kinase 3 (SGK3). Knock-down of endogenous PDPK1 in DU145 and PC3 cells significantly reduced SGK3 phosphorylation while ectopic expression of a constitutively active SGK3 completely abrogated the apoptosis induced by PDPK1. In contrast, no such effect was observed in SGK1 and AKT phosphorylation following PDPK1 knock-down. Importantly, PDPK1 inhibitors (GSK2334470 and BX-795) significantly reduced tumour-specific cell growth and synergized docetaxel sensitivity in PCa cells. In summary, our results demonstrated that PDPK1 mediates PCa cells' survival through SGK3 signalling and suggest that inactivation of this PDPK1-SGK3 axis may potentially serve as a novel therapeutic intervention for future treatment of PCa.

The Impact of Ang-(1-9) and Ang-(3-7) on the Biological Properties of Prostate Cancer Cells by Modulation of Inflammatory and Steroidogenesis Pathway Genes

The local renin–angiotensin system (RAS) plays an important role in the pathophysiology of the prostate, including cancer development and progression. The Ang-(1-9) and Ang-(3-7) are the less known active peptides of RAS. This study examines the influence of these two peptide hormones on the metabolic activity, proliferation and migration of prostate cancer cells. Significant changes in MTT dye reduction were observed depending on the type of angiotensin and its concentration as well as time of incubation. Ang-(1-9) did not regulate the 2D cell division of either prostate cancer lines however, it reduced the size of LNCaP colonies formed in soft agar, maybe through down-regulation of the HIF1a gene. Ang-(3-7) increased the number of PC3 cells in the S phase and improved anchorage-independent growth as well as mobility. In this case, a significant increase in MKI67, BIRC5, and CDH-1 gene expression was also observed as well as all members of the NF-kB family. Furthermore, we speculate that this peptide can repress the proliferation of LNCaP cells by NOS3-mediated G2/M cell cycle arrest. No changes in expression of BIRC5 and BCL2/BAX ratio were observed but a decrease mRNA proapoptotic BAD gene was seen. In the both lines, Ang-(3-7) improved ROCK1 gene expression however, increased VEGF and NOS3 mRNA was only seen in the PC3 or LNCaP cells, respectively. Interestingly, it appears that Ang-(1-9) and Ang-(3-7) can modulate the level of steroidogenic enzymes responsible for converting cholesterol to testosterone in both prostate cancer lines. Furthermore, in PC3 cells, Ang-(1-9) upregulated AR expression while Ang-(3-7) upregulated the expression of both estrogen receptor genes. Ang-(1-9) and Ang-(3-7) can impact on biological properties of prostate cancer cells by modulating inflammatory and steroidogenesis pathway genes, among others.

Progress in Delivery of siRNA-Based Therapeutics Employing Nano-Vehicles for Treatment of Prostate Cancer

Prostate cancer (PCa) accounts for a high number of deaths in males with no available curative treatments. Patients with PCa are commonly diagnosed in advanced stages due to the lack of symptoms in the early stages. Recently, the research focus was directed toward gene editing in cancer therapy. Small interfering RNA (siRNA) intervention is considered as a powerful tool for gene silencing (knockdown), enabling the suppression of oncogene factors in cancer. This strategy is applied to the treatment of various cancers including PCa. The siRNA can inhibit proliferation and invasion of PCa cells and is able to promote the anti-tumor activity of chemotherapeutic agents. However, the off-target effects of siRNA therapy remarkably reduce its efficacy in PCa therapy. To date, various carriers were designed to improve the delivery of siRNA and, among them, nanoparticles are of importance. Nanoparticles enable the targeted delivery of siRNAs and enhance their potential in the downregulation of target genes of interest. Additionally, nanoparticles can provide a platform for the co-delivery of siRNAs and anti-tumor drugs, resulting in decreased growth and migration of PCa cells. The efficacy, specificity, and delivery of siRNAs are comprehensively discussed in this review to direct further studies toward using siRNAs and their nanoscale-delivery systems in PCa therapy and perhaps other cancer types.

Should we keep rocking? Portraits from targeting Rho kinases in cancer

Cancer targeted therapy, either alone or in combination with conventional chemotherapy, could allow the survival of patients with neoplasms currently considered incurable. In recent years, the dysregulation of the Rho-associated coiled-coil kinases (ROCK1 and ROCK2) has been associated with increased metastasis and poorer patient survival in several tumor types, and due to their essential roles in regulating the cytoskeleton, have gained popularity and progressively been researched as targets for the development of novel anti-cancer drugs. Nevertheless, in a pediatric scenario, the influence of both isoforms on prognosis remains a controversial issue. In this review, we summarize the functions of ROCKs, compile their roles in human cancer and their value as prognostic factors in both, adult and pediatric cancer. Moreover, we provide the up-to-date advances on their pharmacological inhibition in pre-clinical models and clinical trials. Alternatively, we highlight and discuss detrimental effects of ROCK inhibition provoked not only by the action on off-targets, but most importantly, by pro-survival effects on cancer stem cells, dormant cells, and circulating tumor cells, along with cell-context or microenvironment-dependent contradictory responses. Together these drawbacks represent a risk for cancer cell dissemination and metastasis after anti-ROCK intervention, a caveat that should concern scientists and clinicians.

Extracellular Histone Promotes Prostate Cancer Migration and Epithelial-Mesenchymal Transition through NF-κB-Mediated Inflammatory Responses

INTRODUCTION

This study aims to explore the relationship betweenextracellular histone and prostate cancer and its mechanism.

METHODS

Migration of prostate cancer cells was detected by Transwell. Inflammatory factor expression was investigated by ELISA. Epithelial-mesenchymal transition and expression of NF-κB pathway-related proteins were investigated using Western blotting.

RESULTS

Under the induction of extracellular histones, the migration rate of prostate cancer cells and the levels of IL-1β, TNF-α, and IL-6 were notably enhanced. Then, expression of E-cadherin was significantly down-regulated, while levels of N-cadherin, vimentin, β-catenin, Snail, p-p65 and p-IκBα were significantly up-regulated, which was reversed by PDTC (pyrrolidine dithiocarbamate).

CONCLUSION

Extracellular histone significantly promotes the progression of prostate cancer cells via NF-κB pathway-mediated inflammatory responses, which may serve as a novel target for treating prostate cancer.

[SRC kinase inhibitor PP2 inhibits invasion and metastasis of lung cancer A549 cells by upregulating connexin43 expression]

OBJECTIVE

To investigate the effect of SRC kinase inhibitor PP2 on the invasion and metastasis of lung cancer A549 cells and explore its molecular mechanism.

METHODS

MTT assay was used to evaluate the inhibitory effect of PP2 on the proliferation of A549 cells. Cell scratch and Transwell assays were performed to assess the invasion and metastatic capacity of A549 cells after treatment with 1, 2, 4, 8, and 16 μmol/L PP2 for 24 h. Western blotting was used to detect the expressions of connexin43 (Cx43) and MMP-2 in the cells after small interfering RNA (siRNA)-mediated silencing or overexpression of Cx43; the changes in the cell invasion and metastasis in response to PP2 treatment after Cx43 silencing or overexpression were investigated.

RESULTS

MTT assay showed that treatment with PP2 at 2, 4, 8, 16, and 32 μmol/L significantly inhibited the proliferation of A549 cells in a concentration-dependent manner. Treatments with PP2 at 1, 2, 4, 8, and 16 μmol/L for 24 h also concentration-dependently lowered the invasion and metastatic abilities of the cells (P < 0.05). At 4 and 8 μmol/L, PP2 significantly increased the expression level of Cx43 protein and decreased the expression level of MMP-2 protein. Overexpression of Cx43 significantly enhanced the inhibitory effect of PP2 on the cell invasion and metastasis, and Cx43 silencing significantly attenuated the inhibitory effect of PP2 (P < 0.05).

CONCLUSIONS

PP2 treatment can suppress the invasion and metastasis of A549 cells in vitro possibly by modulating the expression of Cx43.