Using rDNA ITS2 barcoding to identify kratom (Mitragyna speciosa) from the genus Mitragyna and Neolamarckia cadamba.

This study collected 80 samples of suspected kratom plant powder. A polymerase chain reaction sequence analysis was conducted using two sets of DNA barcode primers for plant ribosomal (r)DNA internal transcribed spacers (ITSs), namely, ITS3/ITS4 and ITS-p3/ITS-u4. Among the 80 samples, 40 were analyzed using the ITS3/ITS4 primer pair, and then DNA sequences were subjected to a National Center for Biotechnology Information-Basic Local Alignment Search Tool (NCBI-BLAST) comparison. Results showed that 29 samples had a 100% match (364/364) with Mitragyna speciosa (kratom), and 6 samples had a 99.73% match (363/364) with M. speciosa, whereas 5 samples had disordered and unreadable sequences. The 5 unreadable samples and an additional 40 suspected kratom samples were then analyzed using the ITS-p3/ITS-u4 primer pair, followed by an NCBI-BLAST comparison. Among these, 32 samples had a 100% match (404/404) with M. speciosa, and 11 samples had a 99.75% match (403/404) with M. speciosa. Among the samples with sequences matching M. speciosa, three distinct types were observed (no variance/404, 287M/404, and 287A/404). One sample had a 99.51% match (404/406) with Neolamarckia cadamba, and another sample had a sequencing length of 305 bp, with 25 positions showing mixed base pairs, indicating a mixture of different species. Analysis of the mixed base pair pattern suggested a possible mixture of M. speciosa and N. cadamba. Actually, M. speciosa and N. cadamba have very similar external morphologies. This indicates that the ITS-p3/ITS-u4 primer pair is effective in distinguishing mixtures of M. speciosa and N. cadamba and is thus more suitable than ITS3/ITS4 for identifying and analyzing samples of suspected kratom plant powder.

Development and technical application of SSR-based individual identification system for Chamaecyparis taiwanensis against illegal logging convictions.

Chamaecyparis taiwanensis is an endemic plant suffering illegal logging in Taiwan for its high economic value. Lack of direct evidence to correlate stump and timber remains a hurdle for law enforcement. In this report, 23 polymorphic Genomic Simple Sequence Repeat (gSSR) and 12 Expressed Sequence Tag (EST)-SSR markers were developed and their transferability was assessed. The individual identification system built from selected non-linkage 30 SSR markers has a combined probability of identity as 5.596 × 10-12 equivalents to identifying an individual in a population of up to 18 million C. taiwanensis with 99.99% confidence level. We also applied the system in an actual criminal case by selecting 19 of these markers to correlate illegally felled timbers and victim trees. Our data demonstrate that molecular signals from three timbers hit with three victim trees with confidence level more than 99.99%. This is the first example of successfully applying SSR in C. taiwanensis as a court evidence for law enforcement. The identification system adapted advanced molecular technology and exhibits its great potential for natural resource management on C. taiwanensis.

Ketamine Increases Permeability and Alters Epithelial Phenotype of Renal Distal Tubular Cells via a GSK-3ß-Dependent Mechanism.

Ketamine, a dissociative anesthetic, is misused and abused worldwide as an illegal recreational drug. In addition to its neuropathic toxicity, ketamine abuse has numerous effects, including renal failure; however, the underlying mechanism is poorly understood. The process called epithelial phenotypic changes (EPCs) causes the loss of cell-cell adhesion and cell polarity in renal diseases, as well as the acquisition of migratory and invasive properties. Madin-Darby canine kidney cells, an in vitro cell model, were subjected to experimental manipulation to investigate whether ketamine could promote EPCs. Our data showed that ketamine dramatically decreased transepithelial electrical resistance and increased paracellular permeability and junction disruption, which were coupled to decreased levels of apical junctional proteins (ZO-1, occludin, and E-cadherin). Consistent with the downregulation of epithelial markers, the mesenchymal markers N-cadherin, fibronectin, and vimentin were markedly upregulated following ketamine stimulation. Of the E-cadherin repressor complexes tested, the mRNA levels of Snail, Slug, Twist, and ZEB1 were elevated. Moreover, ketamine significantly enhanced migration and invasion. Ketamine-mediated changes were at least partly caused by the inhibition of GSK-3ß activity through Ser-9 phosphorylation by the PI3K/Akt pathway. Inhibiting PI3K/Akt with LY294002 reactivated GSK-3ß and suppressed ketamine-enhanced permeability, EPCs, and motility. These findings were recapitulated by the inactivation of GSK-3ß using the inhibitor 3F8. Taken together, these results provide evidence that ketamine induces renal distal tubular EPCs through the downregulation of several junction proteins, the upregulation of mesenchymal markers, the activation of Akt, and the inactivation of GSK-3ß.

Androgen-Induced TMPRSS2 Activates Matriptase and Promotes Extracellular Matrix Degradation, Prostate Cancer Cell Invasion, Tumor Growth, and Metastasis.

Dysregulation of androgen signaling and pericellular proteolysis is necessary for prostate cancer progression, but the links between them are still obscure. In this study, we show how the membrane-anchored serine protease TMPRSS2 stimulates a proteolytic cascade that mediates androgen-induced prostate cancer cell invasion, tumor growth, and metastasis. We found that matriptase serves as a substrate for TMPRSS2 in mediating this proinvasive action of androgens in prostate cancer. Further, we determined that higher levels of TMPRSS2 expression correlate with higher levels of matriptase activation in prostate cancer tissues. Lastly, we found that the ability of TMPRSS2 to promote prostate cancer tumor growth and metastasis was associated with increased matriptase activation and enhanced degradation of extracellular matrix nidogen-1 and laminin ß1 in tumor xenografts. In summary, our results establish that TMPRSS2 promotes the growth, invasion, and metastasis of prostate cancer cells via matriptase activation and extracellular matrix disruption, with implications to target these two proteases as a strategy to treat prostate cancer.

Involvement of calcium-mediated reactive oxygen species in inductive GRP78 expression by geldanamycin in 9L rat brain tumor cells.

Treatment with geldanamycin (GA) leads to an increase in [Ca2+]c and the production of reactive oxygen species (ROS) in rat brain tumor 9L RBT cells. GA-exerted calcium signaling was blocked by BAPTA/AM and EGTA. The effect of GA on [Ca2+]c was significantly reduced in the presence of thapsigargin (TG) and ruthenium red (RR). GA-induced GRP78 expression is significantly decreased in the presence of BAPTA/AM, EGTA and RR, suggesting that the calcium influx from the extracellular space and intracellular calcium store oscillations are contributed to by the calcium mobilization and GRP78 expression induced by GA. The induced GRP78 expression is sensitive to added U73122 and Ro-31-8425, pinpointing the involvement of phospholipase C (PLC) and protein kinase C (PKC) in GA-induced endoplasmic reticulum (ER) stress. The antioxidants N-acetylcysteine (NAC), BAPTA/AM, EGTA and H7 also have significant inhibitory effects on ROS generation. Finally, neither H7 nor NAC was able to affect the calcium response elicited by GA. Our results suggest that the causal signaling cascade during GA-inducted GRP78 expression occurs via a pathway that connects PLC to cytoplasmic calcium increase, PKC activation and, then, finally, ROS generation. Our data provides new insights into the influence of GA on ER stress response in 9L RBT cells.

Curcumin-targeting pericellular serine protease matriptase role in suppression of prostate cancer cell invasion, tumor growth, and metastasis.

Curcumin has been shown to possess potent chemopreventive and antitumor effects on prostate cancer. However, the molecular mechanism involved in curcumin's ability to suppress prostate cancer cell invasion, tumor growth, and metastasis is not yet well understood. In this study, we have shown that curcumin can suppress epidermal growth factor (EGF)- stimulated and heregulin-stimulated PC-3 cell invasion, as well as androgen-induced LNCaP cell invasion. Curcumin treatment significantly resulted in reduced matrix metalloproteinase 9 activity and downregulation of cellular matriptase, a membrane-anchored serine protease with oncogenic roles in tumor formation and invasion. Our data further show that curcumin is able to inhibit the induction effects of androgens and EGF on matriptase activation, as well as to reduce the activated levels of matriptase after its overexpression, thus suggesting that curcumin may interrupt diverse signal pathways to block the protease. Furthermore, the reduction of activated matriptase in cells by curcumin was also partly due to curcumin's effect on promoting the shedding of matriptase into an extracellular environment, but not via altering matriptase gene expression. In addition, curcumin significantly suppressed the invasive ability of prostate cancer cells induced by matriptase overexpression. In xenograft model, curcumin not only inhibits prostate cancer tumor growth and metastasis but also downregulates matriptase activity in vivo. Overall, the data indicate that curcumin exhibits a suppressive effect on prostate cancer cell invasion, tumor growth, and metastasis, at least in part via downregulating matriptase function.

Matriptase is involved in ErbB-2-induced prostate cancer cell invasion.

Deregulation of both ErbB-2 signaling and matriptase activity has been associated with human prostate cancer (PCa) progression. In this communication, we investigated the roles of both ErbB-2 signaling in matriptase zymogen activation and matriptase in ErbB-2-induced PCa malignancy. In a human PCa cell progression model, we observed that advanced PCa C-81 LNCaP cells exhibited an aggressive phenotype with increased cell migration and invasion capacity; these cells concurrently showed both enhanced ErbB-2 phosphorylation and increased matriptase zymogen activation compared with parental C-33 LNCaP cells. Moreover, ErbB2 activation, both ligand-dependent (eg, epidermal growth factor treatment) and ligand-independent (eg, overexpression), was able to induce matriptase zymogen activation in this cell line. Inhibition of ErbB-2 activity by either the specific inhibitor, AG825, in epidermal growth factor-treated C-33 LNCaP cells or ErbB-2 knockdown in C-81 LNCaP cells, reduced matriptase activation. These observations were confirmed by similar studies using both DU145 and PC3 cells. Together, these data suggest that ErbB-2 signaling plays an important role in matriptase zymogen activation. ErbB-2-enhanced matriptase activation was suppressed by a phosphatidylinositol 3-kinase inhibitor (ie, LY294002) but not by a MEK inhibitor (ie, PD98059). Suppression of matriptase expression by small hairpin RNA knockdown in ErbB-2-overexpressing LNCaP cells dramatically suppressed cancer cell invasion. In summary, our data indicate that ErbB-2 signaling via the phosphatidylinositol 3-kinase pathway results in up-regulated matriptase zymogen activity, which contributes to PCa cell invasion.