The prognosis for pancreatic ductal adenocarcinoma (PDAC) remains poor despite decades of effort. The abundant extracellular matrix (ECM) in PDAC comprises a major fraction of the tumor mass and plays various roles in promoting resistance to therapies. However, nonselective depletion of ECM has led to poor patient outcomes. Consistent with that observation, we previously showed that individual matrisome proteins derived from stromal cells correlate with either long or short patient survival. In marked contrast, those derived from cancer cells correlate strongly with poor survival. Here, we studied three cancer cell-derived matrisome proteins that are significantly overrepresented during PDAC progression, AGRN (agrin), SER-PINB5 (serine protease inhibitor B5), and CSTB (cystatin B). Using both overexpression and knockdown experiments, we demonstrate that all three are promoters of PDAC metastasis. Furthermore, these proteins operate at different metastatic steps. AGRN promoted epithelial-to-mesenchymal transition in primary tumors, whereas SERPINB5 and CSTB enhanced late steps in the metastatic cascade by elevating invadopodia formation and in vivo extravasation. All three genes were associated with a poor prognosis in human patients and high levels of SERPINB5, secreted by cancer cells and deposited in the ECM, correlated with poor patient prognosis. This study provides strong evidence that cancer cell-derived matrisome proteins can be causal in promoting tumorigenesis and metastasis and lead to poor patient survival. Therefore, compared with the bulk matrix, mostly made by stromal cells, precise interventions targeting cancer cell-derived matrisome proteins, such as AGRN, SERPINB5, and CSTB, may represent preferred potential therapeutic targets.Significance: This study provides insights into the biological roles of cancer cell-derived matrisome proteins in PDAC and supports the notion that these proteins are protumorigenic and better therapeutic targets.

No abstract

Synthetic biomarkers, bioengineered sensors that generate molecular reporters in diseased microenvironments, represent an emerging paradigm in precision diagnostics. Despite the utility of DNA barcodes as a multiplexing tool, their susceptibility to nucleases in vivo has limited their utility. Here we exploit chemically stabilized nucleic acids to multiplex synthetic biomarkers and produce diagnostic signals in biofluids that can be ‘read out’ via CRISPR nucleases. The strategy relies on microenvironmental endopeptidase to trigger the release of nucleic acid barcodes and polymerase-amplification-free, CRISPR-Cas-mediated barcode detection in unprocessed urine. Our data suggest that DNA-encoded nanosensors can non-invasively detect and differentiate disease states in transplanted and autochthonous murine cancer models. We also demonstrate that CRISPR-Cas amplification can be harnessed to convert the readout to a point-of-care paper diagnostic tool. Finally, we employ a microfluidic platform for densely multiplexed, CRISPR-mediated DNA barcode readout that can potentially evaluate complex human diseases rapidly and guide therapeutic decisions.

Synthetic biomarkers, exogenous probes that generate molecular reporters, represent an emerging paradigm in precision diagnostics with applications across infectious and noncommunicable diseases. In order to achieve their promise, these methods reply on multiplexing strategies to provide tools that are both sensitive and specific. However, the field of synthetic biomarkers has not benefited from molecular strategies such as DNA-barcoding due to the susceptibility of nucleic acids in vivo. Herein, we exploit chemically-stabilized DNAs to tag synthetic biomarkers and produce diagnostic signals via CRISPR nucleases. Our strategy capitalizes on disease-associated, protease-activated release of nucleic acid barcodes and polymerase-amplification-free, CRISPR-Cas-mediated barcode detection in unprocessed biofluids. In murine cancer models, we show that the DNA-encoded urine biomarkers can noninvasively detect and monitor disease progression, and demonstrate that nuclease amplification can be harnessed to convert the readout to a point-of-care tool. This technique combines specificity with ease of use to offer a new platform to study human disease and guide therapeutic decisions.

Objectives Undergraduate ultrasound education is becoming increasingly important, but its expansion is limited by time, space and the availability of trained faculty. In order to validate an alternative and more accessible teaching model, our aim was to assess whether combining teleguidance and peer‐assisted learning to teach ultrasound is as effective as traditional in‐person methods. Methods Peer instructors taught 47 second‐year medical students ocular ultrasound via either teleguidance or traditional in‐person methods. Proficiency was assessed using a multiple‐choice knowledge test and objective structured clinical examination (OSCE). Confidence, overall experience, and experience with a peer instructor were measured using a 5‐point Likert scale. Two one‐sided t‐tests were used to measure equivalency between the two groups. The null hypothesis that the two groups were not different was rejected when P < 0.05. Results The teleguidance group performed as well as the traditional in‐person group in terms of knowledge change, confidence change, OSCE time and OSCE score (p = 0.011, p = 0.006, p = 0.005 and  = 0.004, respectively, indicating the two groups are statistically equivalent). The teleguidance group rated the experience highly overall (4.06/5), but less than the traditional group (4.47/5; P = 0.448, indicating statistical difference). Peer instruction was rated 4.35/5 overall. Conclusion Peer‐instructed teleguidance was equivalent to in‐person instruction with respect to knowledge change, confidence gain and OSCE performance in basic ocular ultrasound.

While the majority of sports medicine literature discusses the incidence and rehabilitation of sports injuries, there is a paucity regarding an athlete’s perception of pain during these injuries. This study describes the relationship between the perception of pain from injuries in a Taekwondo collegiate conference and injury characteristics such as injury type, location, mechanism, time loss, and the athlete’s competitive experience. In our study, we obtained reports from 62 Taekwondo athletes who were injured during the 2008–2009 Pacific West Taekwondo Conference collegiate season. Pain was recorded using the Numeric Rating Scale for Pain during athletes’ acute injury and at two weeks, six weeks, and subsequent monthly follow-ups. Pain scores were highest for sprain/strains (mean 5.4, standard error 0.47) and injuries to the lower body (mean 5.6, standard error 0.36). By mechanism, falls (mean 5.8, standard error 0.67) reported the highest levels of pain. There was a significant positive association between pain and time loss, where an increase in pain score of 1 point was associated with about 0.85 days (standard error 0.37) of time lost from training (p=0.0284). Notably, head injuries, although potentially more devastating and attracting widespread concern, were considered less painful.

Synthetic biomarkers, exogenous probes that generate molecular reporters, represent an emerging paradigm in precision diagnostics with applications across infectious and noncommunicable diseases. These methods use multiplexing strategies to provide tools that are both sensitive and specific. However, the field of synthetic biomarkers has not benefited from molecular strategies such as DNA-barcoding due to the susceptibility of nucleic acids in vivo. Herein, we exploit chemically-stabilized DNAs to tag synthetic biomarkers and produce diagnostic signals via CRISPR nucleases. Our strategy capitalizes on disease-associated, protease-activated release of nucleic acid barcodes and polymerase-amplification-free, CRISPR-Cas-mediated barcode detection in unprocessed biofluids. In murine cancer models, we show that these DNA-encoded nanosensors can noninvasively detect and monitor disease progression, and demonstrate that nuclease amplification can be harnessed to convert the readout to a point-of-care tool. This technique combines specificity with ease of use to offer a new platform to study human disease and guide therapeutic decisions.

<p>Example images for lungs after tail-vein injection and cells with TKS5 immunofluorescence staining.</p>