Advances in plant-derived C-glycosides: Phytochemistry, bioactivities, and biotechnological production.

C-glycosides represent a large group of natural products with a C-C bond between the aglycone and the sugar moiety. They exhibit great structural diversity, wide natural distribution, and significant biological activities. By the end of 2021, at least 754 C-glycosides and their derivatives have been isolated and characterized from plants. Thus far, 66 functional C-glycosyltransferases (CGTs) have been discovered from plants, and provide green and efficient approaches to synthesize C-glycosides. Herein, advances in plant-derived C-glycosides are comprehensively summarized from aspects of structural diversity and identification, bioactivities, and biotechnological production. New strategies to discover novel C-glycosides and CGTs, as well as the applications of biotechnological methods to produce C-glycosides in the future are also discussed.

GuRhaGT, a highly specific saponin 2''-O-rhamnosyltransferase from Glycyrrhiza uralensis.

A highly regio- and donor-specific 2''-O-rhamnosyltransferase GuRhaGT was characterised from the medicinal plant Glycyrrhiza uralensis. GuRhaGT could efficiently catalyse rhamnosylation at 2''-OH of the C-3 glycosyl moiety of triterpenoid saponins.

A highly selective 2''-O-glycosyltransferase from Ziziphus jujuba and De novo biosynthesis of isovitexin 2''-O-glucoside.

A novel and efficient 2''-O-glycosyltransferase ZjOGT38 was identified from Ziziphus jujuba. It could regio-selectively glycosylate 2-hydroxyflavanone C-glycosides. ZjOGT38 allowed de novo biosynthesis of isovitexin 2''-O-glucoside in E. coli.

Cognitive magnetic resonance imaging-ultrasound fusion transperineal targeted biopsy combined with randomized biopsy in detection of prostate cancer.

BACKGROUND: Prostate cancer (PCa) is one of the most common cancers among men. Various strategies for targeted biopsy based on multiparametric magnetic resonance imaging (mp-MRI) have emerged, which may improve the accuracy of detecting clinically significant PCa in recent years. AIM: To investigate the diagnostic efficiency of a template for cognitive MRI-ultrasound fusion transperineal targeted plus randomized biopsy in detecting PCa. METHODS: Data from patients with an increasing prostate-specific antigen (PSA) level but less than 20 ng/mL and at least one lesion suspicious for PCa on MRI from December 2015 to June 2018 were retrospectively analyzed. All patients underwent cognitive fusion transperineal template-guided targeted biopsy followed by randomized biopsy outside the targeted area. A total of 127 patients with complete data were included in the final analysis. A multivariable logistic regression analysis was conducted, and a two-sided P < 0.05 was considered statistically significant. RESULTS: PCa was detected in 66 of 127 patients, and 56 cases presented clinically significant PCa. Cognitive fusion targeted biopsy alone detected 59/127 cases of PCa, specifically 52/59 cases with clinically significant PCa and 7/59 cases with clinically insignificant PCa. A randomized biopsy detected seven cases of PCa negative on targeted biopsy, and four cases had clinically significant PCa. PSA density (OR: 1.008, 95%CI: 1.003-1.012, P = 0.001; OR: 1.006, 95%CI: 1.002-1.010, P = 0.004) and Prostate Imaging-Reporting and Data System (PI-RADS) scores (both P < 0.001) were independently associated with the results of cognitive fusion targeted biopsy combined with randomized biopsy and targeted biopsy alone. CONCLUSION: This single-centered study proposed a feasible template for cognitive MRI-ultrasound fusion transperineal targeted plus randomized biopsy. Patients with higher PSAD and PI-RADS scores were more likely to be diagnosed with PCa.

Dissection of the general two-step di-C-glycosylation pathway for the biosynthesis of (iso)schaftosides in higher plants.

Schaftoside and isoschaftoside are bioactive natural products widely distributed in higher plants including cereal crops and medicinal herbs. Their biosynthesis may be related with plant defense. However, little is known on the glycosylation biosynthetic pathway of these flavonoid di-C-glycosides with different sugar residues. Herein, we report that the biosynthesis of (iso)schaftosides is sequentially catalyzed by two C-glycosyltransferases (CGTs), i.e., CGTa for C-glucosylation of the 2-hydroxyflavanone aglycone and CGTb for C-arabinosylation of the mono-C-glucoside. The two enzymes of the same plant exhibit high homology but remarkably different sugar acceptor and donor selectivities. A total of 14 CGTa and CGTb enzymes were cloned and characterized from seven dicot and monocot plants, including Scutellaria baicalensis, Glycyrrhiza uralensis, Oryza sativa ssp. japonica, and Zea mays, and the in vivo functions for three enzymes were verified by RNA interference and overexpression. Through transcriptome analysis, we found homologous genes in 119 other plants, indicating this pathway is general for the biosynthesis of (iso)schaftosides. Furthermore, we resolved the crystal structures of five CGTs and realized the functional switch of SbCGTb to SbCGTa by structural analysis and mutagenesis of key amino acids. The CGT enzymes discovered in this paper allow efficient synthesis of (iso)schaftosides, and the general glycosylation pathway presents a platform to study the chemical defense mechanisms of higher plants.

Neuroendocrine cells of prostate cancer: biologic functions and molecular mechanisms.

Prostate cancer (PCa) is a major health risk for older men worldwide. Existing systemic therapies mostly target androgen receptor (AR). Although treatments are initially effective, the disease always recurs. A potential mechanism for the treatment failure is that PCa contains, in addition to the AR-positive luminal type tumor cells, a small component of neuroendocrine (NE) cells. The function of NE cells in PCa remains poorly understood, and one important characteristic of these cells is their lack of expression of AR and resistance to hormonal therapy. In addition, many patients develop the more aggressive small-cell neuroendocrine carcinoma (SCNC) after hormonal therapy. Although this clinical phenomenon of disease transformation from adenocarcinoma to SCNC is well established, the cell of origin for SCNC remains unclear. Recently, loss of function of Rb and TP53 and amplification and overexpression of MYCN and Aurora A kinase have been identified as important biomarkers and potential disease drivers. In this article, we systematically review the histology of normal prostate and prostate cancer including the main histologic types: adenocarcinoma and SCNC. We also review the findings from many studies using cellular and animal models as well as human specimens that attempt to understand the molecular mechanisms of treatment failure, disease progression, and tumor transformation from adenocarcinoma to SCNC.

Evaluation of the Prostate Imaging Reporting and Data System for Magnetic Resonance Imaging Diagnosis of Prostate Cancer in Patients with Prostate-specific Antigen <20 ng/ml.

BACKGROUND: The European Society of Urogenital Radiology has built the Prostate Imaging Reporting and Data System (PI-RADS) for standardizing the diagnosis of prostate cancer (PCa). This study evaluated the PI-RADS diagnosis method in patients with prostate-specific antigen (PSA) <20 ng/ml. METHODS: A total of 133 patients with PSA <20 ng/ml were prospectively recruited. T2-weighted (T2WI) and diffusion-weighted (DWI) magnetic resonance images of the prostate were acquired before a 12-core transrectal prostate biopsy. Each patient's peripheral zone was divided into six regions on the images; each region corresponded to two of the 12 biopsy cores. T2WI, DWI, and T2WI + DWI scores were computed according to PI-RADS. The diagnostic accuracy of the PI-RADS score was evaluated using histopathology of prostate biopsies as the reference standard. RESULTS: PCa was histologically diagnosed in 169 (21.2%) regions. Increased PI-RADS score correlated positively with increased cancer detection rate. The cancer detection rate for scores 1 to 5 was 2.8%, 15.0%, 34.6%, 52.6%, and 88.9%, respectively, using T2WI and 12.0%, 20.2%, 48.0%, 85.7%, and 93.3%, respectively, using DWI. For T2WI + DWI, the cancer detection rate was 1.5% (score 2), 13.5% (scores 3-4), 41.3% (scores 5-6), 75.9% (scores 7-8), and 92.3% (scores 9-10). The area under the curve for cancer detection was 0.700 (T2WI), 0.735 (DWI) and 0.749 (T2WI + DWI). The sensitivity and specificity were 53.8% and 89.2%, respectively, when using scores 5-6 as the cutoff value for T2WI + DWI. CONCLUSIONS: The PI-RADS score correlates with the PCa detection rate in patients with PSA <20 ng/ml. The summed score of T2WI + DWI has the highest accuracy in detection of PCa. However, the sensitivity should be further improved.

A new antimicrobial peptide SCY2 identified in Scylla Paramamosain exerting a potential role of reproductive immunity.

A new antimicrobial peptide named SCY2 with 65.08% identity in amino acid sequence to the known scygonadin (SCY1) was first characterized in Scylla paramamosain based on its cloned full-length cDNA and genomic DNA sequences. The SCY2 gene was dominantly expressed in the ejaculatory duct of male crabs and its mRNA transcripts were discerned mainly in the glandular epithelium of the inner wall and the secretion inside the ejaculatory duct. Although the SCY2 gene could not be induced with the challenge of the bacteria and fungi tested, its induction reached the highest level at the peak period of mating in mature male crabs either in June or November, suggesting its induction was likely related to seasonal reproduction changes. Moreover, it was interesting to note that, from analysis of its transcripts and protein, SCY2 was significantly expressed only in the ejaculatory duct of pre-copulatory males before mating, however it was clearly detected in the spermatheca of post-copulatory females after mating accompanied by the decreased level of SCY2 expression in the ejaculatory duct. These results suggested that the SCY2 was probably transferred from the male during mating action with the female for the purpose of protecting fertilization. The recombinant SCY2 was more active against the Gram-positive than the Gram-negative bacteria tested. It was further observed that the SCY2 transcripts were significantly increased with addition of exogenous progesterone in tissue cultures whereas the several other hormones tested had no any effect on SCY2 expression, indicating that there might be a relationship between the SCY2 expression and the induction of hormones in vivo. In summary, this study demonstrated that one role of SCY2 was likely to be involved in crab reproduction and it exerted its reproductive immune function through the mating action and the maintenance of inner sterility in the spermatheca of the female, thus leading to successful fertilization of S. paramamosain.

A novel innexin2 forming membrane hemichannel exhibits immune responses and cell apoptosis in Scylla paramamosain.

Innexins are a class of transmembrane proteins that are important for embryonic development, morphogenesis and electrical synapse formation. In the present study, a novel innexin2 gene from Scylla paramamosain was named Sp-inx2 and characterized. The complete cDNA and genomic DNA sequences of Sp-inx2 were revealed. Sp-inx2 mRNA transcripts were distributed in various tissues of S. paramamosain and were most abundant in the hemocytes. The Sp-inx2 was significantly upregulated in hemocyte, gill and hepatopancreas tissues with the challenge of either Vibrio alginolyticus, Vibrio parahaemolyticus or lipopolysaccharides (LPSs) when analyzed at 3 and 6 h using quantitative real-time PCR, suggesting that it could activate an immune response against the challenge of LPSs or Vibrio species. Using the chemical inhibitors carbenoxolone and probenecid, the absorption of the fluorescent dye Lucifer yellow decreased in the primary cultured hemocytes of crabs, thus confirming that hemichannels composed of Sp-inx2 existed in the crab hemocytes. With LPS stimulation, the level of mRNA transcripts and protein expression of Sp-inx2 in the same cultured hemocytes gradually increased from 6 to 48 h, while the activity of hemichannels was down-regulated at 6 and 12 h, demonstrating that LPSs could modulate the absorption activity of hemichannels in addition to its upregulation of Sp-inx2 gene expression. Furthermore, the dye uptake rate in HeLa cells in which Sp-inx2 was ectopically expressed increased dramatically but the increase was significantly down-regulated with the addition of 50 µg mL(-1) LPS, suggesting that the LPS stimulation could effectively reduce the activity of hemichannels. Interestingly, with the ectopic expression of Sp-inx2 in HeLa and EPC cells, apoptosis spontaneously occurred in both cultured cell lines when detected using TUNEL assay. In summary, a new Sp-inx2 gene was first characterized in a marine animal S. paramamosain and it had a function associated with immune response and cell apoptosis.

Prognostic significance of C-reactive protein in urological cancers: a systematic review and meta-analysis.

BACKGROUND: C-reactive protein (CRP), considered as a prototypical inflammatory cytokine, has been proposed to be involved in tumor progression through inflammation. Recent studies have indicated CRP as a progostic predictor for urological cancers, but the results remain controversial. MATERIALS AND METHODS: A systematic search of Medline, Scopus and the Cochrane Library was performed to identify eligible studies published between Jan 1, 2001 and Sep 1, 2013. Outcomes of interest were collected from studies comparing overall survival (OS), cancer-specific survival (CSS) and relapse-free survival (RFS) in patients with elevated CRP levels and those having lower levels. Studies were pooled, and combined hazard ratio (HR) of CRP with its 95% confidence interval (CI) for survival were used for the effect size estimate. RESULTS: A total of 43 studies (7,490 patients) were included in this meta-analysis (25 for RCC, 10 for UC, and 8 for PC). Our pooled results showed that elevated serum CRP level was associated with poor OS (HR: 1.26, 95%CI: 1.22-1.30) and RFS (HR: 1.38 95%CI: 1.29-1.47), respectively. For CSS the pooled HR (HR: 1.33, 95%CI: 1.28-1.39) for higher CRP expression could strongly predict poorer survival in urological cancers. Simultaneously, elevated serum CRP was also significantly associated with poor prognosis in the subgroup analysis. CONCLUSIONS: Our pooled results demonstrate that a high serum level of CRP as an inflammation biomarker denotes a poor prognosis of patients with urological cancers. Further large prospective studies should be performed to confirm whether CRP, as a biomarker of inflammation, has a prognostic role in urological cancer progression.

Laparoendoscopic single-site radical prostatectomy: technique and initial outcomes.

BACKGROUND: Laparoendoscopic single-site surgery radical prostatectomy (LESS-RP) is a challenging urological procedure and needs to be further evaluated. This study was undertaken to illustrate the safety and initial results of pure LESS-RP with conventional available instruments. METHODS: A prospective clinical database was established in September 2010 to assess the outcome following the introduction of LESS-RP at our institution. By June 2012, six procedures had been performed. The mean patient age was 74.7 (74.0 - 76.0) years. The mean body mass index (BMI) was 23.8 (19.5 - 32.2) kg/m(2). The LESS-RP was preformed through an extra-peritoneal approach using single port access with QudaPort, 0° lens 5 mm flexible tip video-laparoscope and available conventional laparoscopic instruments. Parameters assessed were operative time, estimated blood loss, intra-operative complications, drainage time, postoperative pain score (visual analogue pain scale (VAPS), 0 - 10), pathological results, and postoperative prostate specific antigen (PSA) levels. RESULTS: LESS-RP was completed for all six cases without additional trocar placement or conversion to standard laparoscopic or open radical prostatectomy. The mean operative times were 252.5 (190.0 - 305.0) minutes, estimated blood loss was 300 (100 - 500 ml). There was no documentable intraoperative complication. The mean wound-drainage time was 5.2 (2.0 - 7.0) days, and the first postoperative day VAPS was 0.8 (0 - 3.0). Final pathological staging was pT2aN0M0 in four cases and pT2cN0M0 in two cases. Surgical margins were negative for all cases. The one-month post-operative PSA was less than 0.02 ng/ml in each case. All patients were continent without pad usage at 1 year postoperatively. CONCLUSION: The technique of pure LESS-RP is feasible and early outcomes are acceptable.

[Comparison of natural orifice transumbilical endoscopic surgery versus conventional laparoscopic surgery in renal cyst deroofing].

OBJECTIVE: To compare the safety and feasibility of natural orifice transumbilical endoscopic surgery (NOTES) versus conventional laparoscopic surgery in renal cyst deroofing. METHODS: From May 2010 to August 2011, 8 cases of renal cysts underwent cyst deroofing by the technique of NOTES (Triport) (group A) and 14 cases by conventional laparoscopic surgery (Group B) respectively. The data of patient age, cyst size, operative duration, estimated blood loss, intra-operative complications, drainage duration, post-operative pain score (VAPS) and post-operative hospital stay were recorded and analyzed. RESULTS: The average cyst sizes of groups A and B were 6.6 ± 2.4 and 7.0 ± 2.5 cm. There was no conversion to open surgery in neither groups and no conversion to standard laparoscopic surgery in group A. The operative duration, estimated blood volume, VAPS and post-operative hospital stay of both groups were 49 vs 35 min, 12 vs 10 ml, 0 vs 1 and 4 vs 5 days respectively. The drainage duration was 1 day for both groups. No severe complication, secondary hemorrhage or wound infection occurred in neither groups. As judged by both surgeons and patients, the post-operative cosmetic appearances of group A were better than those of group B. CONCLUSION: The cyst deroofing by NOTES is a safe and feasible option for the treatment of renal cysts. As compared with conventional laparoscopic surgery, NOTES may achieve better cosmetic effects with smaller wounds.

[Role of dietary factors in prostate cancer development].

Diet has long been recognized as a strong factor in prostate carcinogenesis, with nutrients participating in either the development or the prevention of cancer. In this review, we concentrate on the role of dietary factors in prostate cancer development. The most significant dietary factors in prostate carcinogenesis are energy, total fat, animal fat, milk, calcium and red meat. However; evidence from case-control, epidemiological and laboratory studies does not support the causative role of any single nutritional component in prostate cancer development, and many questions remain to be further studied about the association of dietary factors with prostate cancer.