Search

Supplementary Information (5 sections): Study design; Review of prior studies to validate the technical robustness of REMI; Selection of cell-surface biomarkers for REMI of breast tumors; Spectral demultiplexing to quantify SERS NPs; Cell culture and flow cytometry for the validation of conjugated NPs Supplementary Figures (10 figures): Supplementary Figure S1. Linearity and limit-of-detection of spectral measurements. Supplementary Figure S2. REMI of normal tissue (EGFR-negative) and tumor xenograſts (SkBr3, U251, and A431) that express various levels of EGFR. Supplementary Figure S3. Structure and spectra of SERS NPs. Supplementary Figure S4. Flow-cytometry based validation of the binding of targeted NPs to cell-surface receptors on cultured cells. Supplementary Figure S5. REMI enables the detection of double-positive breast tumor (ER+ and HER2+). Supplementary Figure S6. REMI enables the detection of EGFR in a triple-negative breast tumor. Supplementary Figure S7. REMI of fibroadenoma (benign lesion). Supplementary Figure S8. An illustration of a key difference between staining histological tissue sections and fresh tissue surfaces. Supplementary Figure S9. Comparison of traditional single-targeted-agent imaging vs. ratiometric imaging, in which an untargeted agent is used to normalize for the nonspecific accumulation that occurs for all agents. Supplementary Figure S10. Comparison of ROC curves for identification of biomarker expression using (A) a ratiometric imaging strategy (same as Fig. 5B) and (B) a traditional single-targeted-agent strategy. Supplementary Table S1. Benign lesions. Supplementary Table S2. Molecular profile of patients.

Intraoperative identification of carcinoma at lumpectomy margins would enable reduced re-excision rates, which are currently as high as 20% to 50%. Although imaging of disease-associated biomarkers can identify malignancies with high specificity, multiplexed imaging of such biomarkers is necessary to detect molecularly heterogeneous carcinomas with high sensitivity. We have developed a Raman-encoded molecular imaging (REMI) technique in which targeted nanoparticles are topically applied on excised tissues to enable rapid visualization of a multiplexed panel of cell surface biomarkers at surgical margin surfaces. A first-ever clinical study was performed in which 57 fresh specimens were imaged with REMI to simultaneously quantify the expression of four biomarkers HER2, ER, EGFR, and CD44. Combined detection of these biomarkers enabled REMI to achieve 89.3% sensitivity and 92.1% specificity for the detection of breast carcinoma. These results highlight the sensitivity and specificity of REMI to detect biomarkers in freshly resected tissue, which has the potential to reduce the rate of re-excision procedures in cancer patients. Cancer Res; 77(16); 4506–16. ©2017 AACR.

Freshwater in both natural and man-made stores is critical for socioeconomic development. Globally, cumulative reduction in terrestrial water storage from 1971 to 2020 is estimated to be of the order of 27,079 Bm3. Although insignificant in comparison to the total volume stored, the decrease in ‘operational’ water stored (i.e., the proportion of water storage that is sustainably utilizable by people) is estimated to be of the order of 3% to 5% since 1971. In many places, both natural and man-made water storage are declining simultaneously, exacerbating water stress. Conjunctive use of different water stores is a prerequisite for water security and it is vital that natural water stores are fully integrated, alongside man-made water infrastructure, in future water resources planning and management.

Intraoperative identification of carcinoma at lumpectomy margins would enable reduced re-excision rates, which are currently as high as 20% to 50%. Although imaging of disease-associated biomarkers can identify malignancies with high specificity, multiplexed imaging of such biomarkers is necessary to detect molecularly heterogeneous carcinomas with high sensitivity. We have developed a Raman-encoded molecular imaging (REMI) technique in which targeted nanoparticles are topically applied on excised tissues to enable rapid visualization of a multiplexed panel of cell surface biomarkers at surgical margin surfaces. A first-ever clinical study was performed in which 57 fresh specimens were imaged with REMI to simultaneously quantify the expression of four biomarkers HER2, ER, EGFR, and CD44. Combined detection of these biomarkers enabled REMI to achieve 89.3% sensitivity and 92.1% specificity for the detection of breast carcinoma. These results highlight the sensitivity and specificity of REMI to detect biomarkers in freshly resected tissue, which has the potential to reduce the rate of re-excision procedures in cancer patients. Cancer Res; 77(16); 4506–16. ©2017 AACR.

Surface-enhanced Raman scattering (SERS) nanoparticles (NPs) are increasingly being engineered for a variety of disease-detection and treatment applications. For example, we have previously developed a fiber-optic Raman-encoded molecular imaging (REMI) system for spectral imaging of biomarker-targeted SERS NPs topically applied on tissue surfaces to identify residual tumors at surgical margins. Although accurate tumor detection was achieved, the commercial SERS NPs used in our previous studies lacked the signal strength to enable high-speed imaging with high pixel counts (large fields of view and/or high spatial resolution), which limits their use for certain time-constrained clinical applications. As a solution, we explored the use of surface-enhanced resonant Raman scattering (SERRS) NPs to enhance imaging speeds. The SERRS NPs were synthesized de novo, and then conjugated to HER2 antibodies to achieve high binding affinity, as validated by flow cytometry. Under identical tissue-staining and imaging conditions, the targeted SERRS NPs enabled reliable identification of HER2-overexpressed tumor xenografts with 50-fold-enhanced imaging speed compared with our standard targeted SERS NPs. This enables our REMI system to image tissue surfaces at a rate of [Formula: see text] per minute at a spatial resolution of 0.5 mm.

We demonstrate that topical staining and spectral imaging of fresh tissues with a mixture of biomarker-targeted SERS nanoparticles allows for rapid (~15 min) detection of tumors in rat esophagi or at the surgical margin surfaces.