pH low insertion peptide mediated cell division cycle-associated protein 1 -siRNA transportation for prostatic cancer therapy targeted to the tumor microenvironment

Prognostic value of cell division cycle-associated protein-3 in prostate cancer

BACKGROUND

The study was aimed to explore cell division cycle-associated protein-3 (CDCA3) expression and its correlation with clinicopathological characteristics, and identification of co-expressed genes of CDCA3 in prostate cancer (PCa).

METHODS

Data for CDCA3 mRNA expression in PCa were obtained from The Cancer Genome Atlas database. Furtherly, CDCA3 protein expression was examined by immunohistochemistry in 80 cases, including 20 normal prostate samples and 60 PCa samples. Then we used "survival" package to obtain the differentially expressed CDCA3 mRNA associated with prognosis of PCa patients. "pROC" package was used to analyze receiver operating characteristic of CDCA3. We used chi-square test, Kruskal-Wallis test and Wilcoxon rank sum test to identify clinicopathological parameters that correlated with CDCA3 expression. In order to determine the effects of CDCA3 expression and clinicopathological parameters on survival, univariate cox regression analysis was performed. Finally, the co-expressed genes of CDCA3 in PCa were explored by search tool for the retrieval of interacting genes, Kyoto encyclopedia of genes and genomes enrichment analysis and Spearman correlation analysis.

RESULTS

In this study, we found that CDCA3 expression was increased in PCa. PCa patients with higher CDCA3 expression had poor outcomes. In terms of receiver operating characteristic, CDCA3 had an area under the curve of 0.857. High CDCA3 expression was positively correlated with advanced T stage, N stage, Gleason score, and served as an independent predictor of progress free interval in PCa patients. Then 20 proteins closely related to CDCA3 were screened through STRING website. Functional enrichment analysis revealed that, Kyoto encyclopedia of genes and genomes pathway was mainly enriched in cell cycle, including 6 genes, BUB1, CCNA2, CDK1, CDC20, TTK, and CCNB2.

CONCLUSION

CDCA3 is significantly associated with the prognosis of PCa, which may be an indicator of the diagnosis and prognosis of PCa and a new therapeutic target.

Regulators CDCA8 as potential targets and biomarkers for the prognosis of human skin cutaneous melanoma

Cutaneous melanoma (CM) is considered as the most malignant skin tumor with high distant metastasis and poor prognosis. Cell division cycle-associated protein (CDCA) family has a role in regulating cell proliferation and modulating immune cell and tumor cell proliferation in the tumor microenvironment to regulate tumor oncogenesis, development and affect patient outcomes. However, the differential expression pattern and prognostic value of CDCA factors (CDCAs) have not been clarified. In this study, the role of CDCAs in CM was analyzed by using bioinformatics and found that the transcriptional expressions of CDCA1/2/3/5/6/8 were upregulating in CM samples than in normal compares. CM patients with downregulated of CDCA1/3/4/5/6/8 and high transcriptional levels of CDCA7 suggest a significantly better prognosis. Furthermore, the significant correlations among the expression of CDCAs and the infiltration of immune cells. In terms of the protein level, we found CDCA8 was upregulated in CM patients. In conclusion, CDCA8 is a powerful prognostic biomarker for CM and can be a novel target for immunotherapy.

Ca2+ -dependent interactions between lipids and the tumor-targeting peptide pHLIP

Cancerous tissues undergo extensive changes to their cellular environments that differentiate them from healthy tissues. These changes include changes in extracellular pH and Ca2+ concentrations, and the exposure of phosphatidylserine (PS) to the extracellular environment, which can modulate the interaction of peptides and proteins with the plasma membrane. Deciphering the molecular mechanisms of such interactions is critical for advancing the knowledge-based design of cancer-targeting molecular tools, such as pH-low insertion peptide (pHLIP). Here, we explore the effects of PS, Ca2+ , and peptide protonation state on the interactions of pHLIP with lipid membranes. Cellular studies demonstrate that exposed PS on the plasma membrane promotes pHLIP targeting. The magnitude of this effect is dependent on extracellular Ca2+ concentration, indicating that divalent cations play an important role in pHLIP targeting in vivo. The targeting mechanism is further explored with a combination of fluorescence and circular dichroism experiments in model membranes and microsecond-timescale all-atom molecular dynamics simulations. Our results demonstrate that Ca2+ is engaged in coupling peptide-lipid interactions in the unprotonated transmembrane conformation of pHLIP. The simulations reveal that while the pH-induced insertion leads to a strong depletion of PS around pHLIP, the Ca2+ -induced insertion has the opposite effect. Thus, extracellular levels of Ca2+ are crucial to linking cellular changes in membrane lipid composition with the selective targeting and insertion of pHLIP. The characterized Ca2+ -dependent coupling between pHLIP sidechains and PS provides atomistic insights into the general mechanism for lipid-coupled regulation of protein-membrane insertion by divalent cations.

Bioinformatics analysis of the clinical relevance of CDCA gene family in prostate cancer

BACKGROUND

Prostate cancer (PCa) is the second most frequent cancer in men worldwide, and its mortality rate is increasing every year. The cell division cycle-associated (CDCA) gene family plays vital roles in the cell cycle process, but an analysis of these proteins in PCa is still lacking.

METHODS

UALCAN and GEPIA were used to examine the transcriptional data and survival of the CDCA gene family in PCa patients. CDCA genetic alterations, prognostic value of genetic alterations, and correlations of CDCAs with each other in PCa were downloaded from cBioPortal. The functional enrichment data of CDCA-related genes were analyzed using DAVID.

RESULTS

Six CDCA genes were upregulated in PCa tissues relative to those in normal tissues (P < .001), including NUF2, CDCA2, CDCA3, CDCA5, CBX2, and CDCA8. The expression levels of the 6 CDCAs were related to the tumor Gleason score (P < .05). In addition, survival analysis using GEPIA suggested that PCa patients with increased NUF2, CBX2, and CDCA2/3/5/8 expression levels had poor relapse-free survival (P < .05). Distinct patterns of genetic alterations of the 6 CDCAs were observed in PCa, and pairwise comparison of the mRNA expression of the 6 CDCAs displayed a close relationship. The biological functions of CDCA-related genes are principally associated with the activation of the following pathways: cell cycle, Fanconi anemia pathway, microRNAs in cancer, oocyte meiosis, and homologous recombination.

CONCLUSIONS

Upregulated CDCA (NUF2, CBX2, and CDCA2/3/5/8) expression in PCa tissues may play a crucial role in the occurrence of PCa. These CDCAs can predict relapse-free survival prognosis and the Gleason score of patients with PCa. Moreover, CDCAs probably exert their functions in tumorigenesis through the cell cycle and miRNAs in the cancer pathway.

Roles of key residues and lipid dynamics reveal pHLIP-membrane interactions at intermediate pH

The pH-low insertion peptide (pHLIP) and its analogs sense the microenvironmental pH variations in tumorous cells and serve as useful anticancer drug deliveries. The pHLIP binds peripherally to membranes and adopts random coil conformation at the physiological pH. The peptide switches from random coil to α-helical conformation and inserts unidirectionally into membrane bilayers when pH drops below a critical transition value that has been routinely determined by the Trp fluorescence spectroscopy. Recent high-resolution studies using solid-state NMR spectroscopy revealed the presence of thermodynamically stable intermediate states of membrane-associated pHLIP around the fluorescence-based transition pH-value. However, the molecular structural features and their mechanistic roles of these intermediate states in the pH-driven membrane insertion process of pHLIP remain largely unknown. This work utilizes solid-state NMR spectroscopy to explore 1) the mechanistic roles of key proline and arginine residues within the pHLIP sequence at intermediate pH-values, and 2) the changes in lipid dynamics at intermediate pH-values in multiple types of model bilayers with anionic phospholipid and/or cholesterol. Our results demonstrate several molecular structural and dynamics changes at around the transition pH-values, including the isomerization of proline-threonine backbone configuration, breaking of arginine-aspartic acid salt bridge and the formation of arginine-lipid interactions, and a universal decreasing of dynamics in lipid headgroups and alkyl chains. Overall, the outcomes provide important insights on the molecular interactions between pHLIP and membrane bilayers at intermediate pH-values and, therefore, prompt the understanding of pH-driven membrane insertion process of this anticancer drug-delivering peptide.

CDCA1/2/3/5/7/8 as novel prognostic biomarkers and CDCA4/6 as potential targets for gastric cancer

Background

Increasing evidence had suggested that cell division cycle-associated (CDCA) family proteins play prominent roles in multiple types of cancer. However, the expression pattern and prognostic value of CDCAs in gastric cancer were still poorly understood.

Methods

In this study, bioinformatics was used for the first time to comprehensively discuss the expression changes of the CDCA protein family in gastric cancer. We studied the transcription and survival data of CDCAs in patients with gastric cancer in Oncomine, GEPIA, DAVID, cBioportal, and other databases.

Results

We identified that the CDCA 1/2/3/4/5/6/7/8 were overexpressed gastric cancer than in normal tissues. There was no significant difference in CDCAs expression among different gastric cancer stages. High expression of CDCA4/6 in patients with gastric cancer was closely related to low overall survival (OS), first progression survival (FPS), and post-progression survival (PPS). In contrast, high CDCA1/2/3/5/7/8 expression predicted a better prognosis. The genetic mutation rate of CDCA2 and CDCA4 was 4%, ranking first. The main biological process of CDCAs protein family enrichment was cell division, the main cell component involved was centromeres of chromosomes, and the main molecular function involved was protein binding.

Conclusions

The study suggested that CDCA1/2/3/5/7/8 were expected to be new prognostic markers for gastric cancer, and CDCA4/6 might be potential targets for the treatment of gastric cancer.

The roles of the cell division cycle-associated gene family in hepatocellular carcinoma

Background

The members of the cell division cycle-associated (CDCA) gene family are significant regulators of cell proliferation known to play key roles in various cancers. However, the function of CDCA genes in hepatocellular carcinoma (HCC) is unclear. The aim of this research was to clarify the roles of CDCA family members in HCC using bioinformatics analysis tools.

Methods

We studied data on the mRNA and protein expression of CDCA genes and survival in patients with HCC using the Oncomine, UALCAN, HPA, CCLE, LinkedOmics, cBioPortal, and Metascape databases.

Results

Significant overexpression of all CDCA members was found in HCC tissues. The expression levels of CDCAs were related to the tumor stage, and high expression levels were correlated with a low survival rate in patients with HCC. Also, we observed a high mutation rate (45%) of CDCAs in the HCC samples, which manifested as deep deletion, amplification, or increased mRNA expression. In the correlation analysis, we found that any 2 CDCA members were significantly positively correlated with each other. Cycle-related genes including AHCTF1, AKT1, BIRC5, CENPF, CENPL, and CENPQ were closely associated with CDCA gene alterations.

Conclusions

The findings of this study indicate that CDCAs may be potential therapeutic targets and prognostic indicators for patients with HCC.

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.

Targeting Acidic Diseased Tissues by pH-Triggered Membrane-Associated Peptide Folding

The advantages of targeted therapy have motivated many efforts to find distinguishing features between the molecular cell surface landscapes of diseased and normal cells. Typically, the features have been proteins, lipids or carbohydrates, but other approaches are emerging. In this discussion, we examine the use of cell surface acidity as a feature that can be exploited by using pH-sensitive peptide folding to target agents to diseased cell surfaces or cytoplasms.

Magnetically-stimulated transformations in nanostructure of lipid mesophases: Effect of structure of iron oxide nanoparticles

Nanostructured lipid-based liquid crystalline (LLC) systems can display different drug release rates and also be stimuli-responsive, rendering them the potential to serve as 'on-demand' drug delivery systems. In this study, a magnetically-responsive cubic phase nanocomposite was engineered by doping iron oxide nanoparticles (IONPs) into a phytantriol (PHYT)-based lipid that exhibits transformation in nanostructure under external alternating magnetic field (AMF). The effects of IONP surface hydrophilicity/hydrophobicity, size and concentration were determined in dispersed systems, and the effect of hydration state of the system was also assessed. Time-resolved small angle X-ray scattering (SAXS) was used to probe the impact of these variables on the transformation of nanostructure with and without the application of AMF. The inclusion of both hydrophobic and hydrophilic IONPs reduced the temperature of the phase transition from the inverted bicontinuous cubic (V₂) phase to inverted hexagonal (H₂) phase and imparted magnetic-responsiveness to the systems. The size of the IONPs played an important role in governing the phase reversibility of the dispersed systems, while the concentration of the IONPs had more impact on the phase behaviour of the bulk systems. These successfully demonstrated a completely reversible magneto-responsive phase transition in the nanostructured LLC systems through optimising the selection of IONPs.