A Protease-Activated Fluorescent Probe Allows Rapid Visualization of Keratinocyte Carcinoma during Excision

Walker, Ethan; Liu, Yiqiao; Kim, In Young; Biro, Mark; Iyer, Sukanya Raj; Ezaldein, Harib H.; Scott, Jeffrey F.; Merati, Miesha; Mistur, Rachel L.; Zhou, Bo; Straight, Brian; Yim, Joshua J.; Bogyo, Matthew; Mann, Margaret; Wilson, David L.; Basilion, James P.; Popkin, Daniel L.

doi:10.1158/0008-5472.can-19-3067

Cited by 16 publications

(11 citation statements)

References 67 publications

(73 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Testing of gel#30 using a human lumpectomy sample showed a strong, robust, and specific ICG signal at the area of BCa ( Figure 6 ). This single application of AKRO-QC-ICG imaging gel in its current formulation fully corroborates our previous clinical studies [ 30 , 31 , 49 ] and builds a strong case to support the clinical merit of topical application of imaging probes as an approach to optically visualize cancer tissue both ex vivo and in vivo. Most recently, de Jongh et al [ 56 ] reported on the discrepancy between true negative margins and those obtained after using IV-administered FIGS.…”

Section: Discussionsupporting

confidence: 86%

“…In addition, fluorescent SBPs can be rendered optically silent by the addition of a quenching moiety that is lost upon reaction with the protease target of interest, ensuring that the probes only produce a signal in tumor tissue when acted upon by an enzyme activity associated with a tumor or its surrounding margins [ 47 ]. In our more recent work, we have developed a method for topical application of imaging probes to tissues using topical application of both quenched activity-based probes [ 28 , 29 , 48 ] and a third generation quenched SBP [ 31 , 49 ]. Topical application into the surgical cavity to identify remaining or “missed” cancer following lumpectomy has the potential to reduce positive surgical margins and integrates well into the surgical workflow.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Formulation of a Thermosensitive Imaging Hydrogel for Topical Application and Rapid Visualization of Tumor Margins in the Surgical Cavity

Walker

Linders

Abenojar

et al. 2022

Cancers

Self Cite

View full text Add to dashboard Cite

Background: Tumor-positive surgical margins during primary breast cancer (BCa) surgery are associated with a two-fold increase in the risk of local recurrence when compared with tumor-negative margins. Pathological microscopic evaluation of the samples only assesses about 1/10 of 1% of the entire volume of the removed BCa specimens, leading to margin under-sampling and potential local recurrence in patients with pathologically clean margins, i.e., false negative margins. In the case of tumor-positive margins, patients need to undergo re-excision and/or radiation therapy, resulting in increases in complications, morbidity, and healthcare costs. Development of a simple real-time imaging technique to identify residual BCa in the surgical cavity rapidly and precisely could significantly improve the quality of care. Methods: A small-molecule, fluorescently quenched protease-substrate probe, AKRO-QC-ICG, was tested as part of a thermosensitive imaging gel formulated for topical application and imaging of the BCa surgical cavity. Results: More than forty formulations of gel mixtures were investigated to enable easy fluid application and subsequent solidification once applied, preventing dripping and pooling in the surgical cavity. The final formulation was tested using human BCa orthotopic implants in nude and NSG patient-derived xenografts (PDX) mice. This formulation of Pluronic F-127/DMSO/AKRO-QC-ICG imaging gel was found to be a good solvent for the probe, with a desirable thermo-reversible solid–gel transition and mechanical strength for distribution of AKRO-QC-ICG on the surfaces of tissue. It demonstrated excellent ability to detect BCa tissue after 10 min exposure, with a high signal-to-noise ratio both in mouse xenografts and freshly excised human lumpectomy tissue. The in vivo efficacy of the AKRO-QC-ICG imaging gel to detect BCa revealed the levels of sensitivity/specificity = 0.92/1 in 12 nude mice, which was corroborated with the sensitivity/specificity = 0.94/1 in 10 PDX mice. Conclusions: Utilization of Pluronic F-127/DMSO/AKRO-QC-ICG imaging gel for topical application to detect BCa in the surgical cavity during surgery has the potential to reduce re-excisions, with consequent savings in healthcare costs and enhancement in patient quality of life.

show abstract

Section: Discussionsupporting

confidence: 86%

Section: Introductionmentioning

confidence: 99%

Formulation of a Thermosensitive Imaging Hydrogel for Topical Application and Rapid Visualization of Tumor Margins in the Surgical Cavity

Walker

Linders

Abenojar

et al. 2022

Cancers

Self Cite

View full text Add to dashboard Cite

show abstract

“…Given this degree of posttranslational regulation, quantifying protease activity, rather than transcriptomic or proteomic analyses, is often required to understand the biological roles of proteases 5 . This has motivated the development of activity-based sensorsprobes that quantify protease activitywhich are used for early detection of disease [6][7][8][9][10][11] , biological imaging [12][13][14] , and drug screening 15,16 . The two primary compositions of activity-based sensors are (1) substrates that produce a signal upon proteolysis and (2) probes that bind active proteases 17 .…”

Section: Introductionmentioning

confidence: 99%

Embracing enzyme promiscuity with activity-based compressed biosensing

Holt

Lim

et al. 2022

Preprint

View full text Add to dashboard Cite

Genome-scale activity-based profiling of proteases requires identifying substrates that are specific to each individual protease. However, this process becomes increasingly difficult as the number of target proteases increases because most substrates are promiscuously cleaved by multiple proteases. We introduce a method - Substrate Libraries for Compressed sensing of Enzymes (SLICE) - for selecting complementary sets of promiscuous substrates to compile libraries that classify complex protease samples (1) without requiring deconvolution of the compressed signals and (2) without the use of highly specific substrates. SLICE ranks substrate libraries according to two features: substrate orthogonality and protease coverage. To quantify these features, we design a compression score that was predictive of classification accuracy across 140 in silico libraries (Pearson r = 0.71) and 55 in vitro libraries (Pearson r = 0.55) of protease substrates. We demonstrate that a library comprising only two protease substrates selected with SLICE can accurately classify twenty complex mixtures of 11 enzymes with perfect accuracy. We envision that SLICE will enable the selection of peptide libraries that capture information from hundreds of enzymes while using fewer substrates for applications such as the design of activity-based sensors for imaging and diagnostics.

show abstract

“…The main disadvantage of the technique is due to the preliminary sample processing that may not be fully reproducible. Many methods using fluorescent dyes injected into the patient or incubated with the tissue specimen are under development [13][14][15][16][17][18], showing high sensitivity and specificity but restricted to surface imaging with low tissue penetration and requiring a long process for the identification and authorisation of the proper candidate for a given tumour. Quantitative micro-elastography (QME) is an emerging technique that produces images of tissue microscale elasticity and has also been recently proposed for margin assessment in cancers that are known to exhibit altered mechanical properties [19], but the difficult interpretation of the images obtained remains the main drawback for this technology.…”

Section: Introductionmentioning

confidence: 99%

Low-Field NMR Relaxometry for Intraoperative Tumour Margin Assessment in Breast-Conserving Surgery

Bitonto

Ruggiero

Pittaro

et al. 2021

Cancers

View full text Add to dashboard Cite

As conserving surgery is routinely applied for the treatment of early-stage breast cancer, the need for new technology to improve intraoperative margin assessment has become increasingly important. In this study, the potential of fast field-cycling 1H-NMR relaxometry as a new diagnostic tool was evaluated. The technique allows the determination of the tissue proton relaxation rates (R1), as a function of the applied magnetic field, which are affected by the changes in the composition of the mammary gland tissue occurring during the development of neoplasia. The study involved 104 small tissue samples obtained from surgical specimens destined for histopathology. It was found that a good accuracy in margin assessment, i.e., a sensitivity of 92% and a specificity of 85%, can be achieved by using two quantifiers, namely (i) the slope of the line joining the R1 values measured at 0.02 and 1 MHz and (ii) the sum of the R1 values measured at 0.39 and 1 MHz. The method is fast, and it does not rely on the expertise of a pathologist or cytologist. The obtained results suggest that a simplified, low-cost, automated instrument might compete well with the currently available tools in margin assessment.

show abstract

A Protease-Activated Fluorescent Probe Allows Rapid Visualization of Keratinocyte Carcinoma during Excision

Abstract: are co-founders, and Brian Straight is the CEO of Akrotome Imaging, Inc. Daniel Popkin is a scientific advisory board member for Akrotome Imaging, Inc. No potential conflicts of interest are disclosed by the other authors.

Cited by 16 publications

References 67 publications

Formulation of a Thermosensitive Imaging Hydrogel for Topical Application and Rapid Visualization of Tumor Margins in the Surgical Cavity

Formulation of a Thermosensitive Imaging Hydrogel for Topical Application and Rapid Visualization of Tumor Margins in the Surgical Cavity

Embracing enzyme promiscuity with activity-based compressed biosensing

Low-Field NMR Relaxometry for Intraoperative Tumour Margin Assessment in Breast-Conserving Surgery

Contact Info

Product

Resources

About