Fluorescence-guided molecular imaging may improve colorectal cancer (CRC) patient outcomes by enabling early detection and better surgical treatment, relying on developing targeted fluorescent tracers to highlight tumours. This study investigates visualising primary colon tumours by topically applying EMI-137, a targeted fluorescent tracer designed to bind to c-Met receptor. We introduce a novel viscous formulation to enhance the tracer's performance, aiming for a clear, robust fluorescent signal by improving contact with mucosal surface of ex vivo colon specimens. We evaluated fluorescence properties of EMI-137 in phosphate-buffered saline (PBS) and in methylcellulose (m-cellulose) and determined emission spectrum of the tracer in both formulations. Flow cytometry was used to determine EMI-137's specificity for c-Met receptor and its optimal concentration. Live-cell imaging visually confirmed EMI-137's fluorescence signal for the c-Met receptor, highlighting its distinctive characteristics across various solvents. In a prospective cohort study, freshly excised colon cancer specimens were incubated with EMI-137 in PBS or m-cellulose. Specimens underwent a meticulous washing process. Near-infrared fluorescence imaging was performed and compared with histopathological analysis to validate detection accuracy. Fluorospectrometry showed that m-cellulose enhanced EMI-137's fluorescence intensity compared to PBS. Flow cytometry showed dose-dependent binding of EMI-137 in HT-29 cells, with an optimum at 500 nM. Microscopy confirmed targeting of c-Met receptors. Topical EMI-137 dissolved in m-cellulose visualised colon tumours effectively, resulting in a high tumour-to-background ratio. Histopathological analysis confirmed c-Met expression in these colon tumours. EMI-137 in a novel viscous vehicle effectively imaged c-Met expressing colon tumors, potentially facilitating fluorescent-guided tumor imaging.

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with a 5-year survival rate of approximately 5-7%, and complete surgical resection remains the only curative treatment but is often unfeasible. Fluorescence-guided surgery (FGS) using tumor-targeted probes may improve tumor visualization and facilitate complete resection. This study aimed to identify and validate tumor targets for FGS during PDAC resection procedures. RNA expression data from over 4000 cell surface genes, obtained from public genomic databases, were analyzed to identify genes encoding PDAC-associated proteins. Eleven potential tumor targets were identified, including CEACAM5, TMPRSS4, COL17A1, CLDN18, and AQP5. Protein expression was evaluated by immunohistochemistry (IHC) in tissues from 44 PDAC and 7 chronic pancreatitis (CP) patients. All targets, except COL17A1, showed significantly higher expression in PDAC tissue compared to healthy pancreatic, CP, and duodenal tissue (p < 0.001), as well as in tumor-positive versus tumor-negative lymph nodes. Especially CEACAM5, TMPRSS4, and AQP5 were identified as the most promising targets for distinguishing PDAC from healthy tissues and detecting lymph node metastasis during FGS. The development of probes targeting multiple markers, such as AQP5 with CEACAM5 and/or TMPRSS4, may help overcome interpatient variability and enhance detection across patients.

Background: Rectal cancer (RC) patients with a clinical complete response (cCR) after neoadjuvant chemoradiotherapy (nCRT) may qualify for a watch-and-wait (W&W) approach. However, a 20–30% local tumor regrowth rate highlights challenges in identifying true responders. This study explores markers for future near-infrared fluorescence tumor imaging by endoscopy to differentiate responders and the effect of nCRT on their expression. Methods: RC samples (n = 51) were collected from both pre-treatment biopsies and corresponding post-treatment surgical specimens. Samples were categorized by treatment response and determined using tumor regression grade (TRG) scoring. Immunohistochemistry assessed the expression of CEA, EpCAM, EGFR, and c-MET in tumors and adjacent normal tissues. Expression levels were quantified using H-scores (0–3), combining the percentage and intensity of stained cells. Pre- and post-treatment H-scores were compared to evaluate the impact of nCRT. Results: CEA, EpCAM, and c-MET were overexpressed in tumor tissue as compared to adjacent healthy mucosa in 100% (51/51), 98.4% (50/51), and 92% (47/51) of tumor biopsies, respectively, while EGFR showed no overexpression. A tumor-to-normal (T/N) ratio ≥ 2 was considered sufficient for differentiation in molecular fluorescence imaging. In pre-treatment biopsy samples, c-MET showed the highest T/N expression ratio (53% of the samples ≥ 2), followed by CEA (26.3%) and EpCAM (16%). Following nCRT treatment, CEA and c-MET maintained a ≥ 2 differential expression in 45% of all samples, whereas EpCAM exhibited this difference in only 9.2% of cases. Neoadjuvant therapy even significantly improved the T/N expression ratio for CEA and c-MET (p < 0.01) and EpCAM (p < 0.05), while EGFR expression remained lower than adjacent normal tissue. Significant increases in all marker expressions were observed in minimal responders (TRG4/5, p < 0.01–0.001), while near-complete responders (TRG2) exhibited non-significant changes in CEA, c-MET, and EGFR expression. Conclusions: c-MET and CEA emerged as optimal tumor imaging targets, showing sustained differential expression after nCRT. In vivo fluorescence-guided endoscopy using probes against these markers could play a role in future clinical decision-making.

Near-infrared fluorescence (NIRF) imaging assists surgeons intraoperatively to achieve radical resection of malignant tissue with one centimeter depth and can be supplemented with photoacoustic imaging to increase depth-of-view. Tumor-associated carbohydrate antigens are promising targets for tumor imaging with potential advantages over protein targeting. This study preclinically evaluates the anti-glycan tracers CH88.2-800CW (anti-Lea/c/x) and CH129-800CW (anti-sdi-Lea) for bimodal NIRF/PA imaging of gastrointestinal cancers. Using immunohistochemistry, we found that Lea/c/x and sdi-Lea were highly expressed in gastric and colorectal cancer tissue, with limited expression in healthy surrounding tissue, except for strong Lea/c/x expression in healthy colorectal epithelium. Bimodal NIRF/PA imaging using CH88.2-800CW and CH129-800CW was performed on subcutaneous and orthotopic HT-29_luc2 (colon cancer) and BxPC-3_luc2 (pancreatic cancer) tumor-bearing mice, using rituximab-800CW as a negative control tracer. At 96 h post-injection, all orthotopic tumors were delineated using the clinical Artemis NIRF imager with mean CH88.2-800CW and CH129-800CW tumor-to-background ratios of 4.8 ± 1.4 and 4.9 ± 0.5 for the HT-29_luc2 model, and 2.5 ± 0.3 and 2.9 ± 0.4 for the BxPC-3_luc2 model, respectively. Similarly specific photoacoustic signal was observed within all tumors for both CH88.2-800CW and CH129-800CW. Biodistribution analyses showed high tumor fluorescence with minimal signal in healthy organs, including the liver and kidneys. Bimodal NIRF/PA imaging employing CH88.2-800CW and CH129-800CW facilitates real-time, high-contrast gastrointestinal tumor visualization. Given their strong and mostly tumor-specific expression, both tracers hold promise as effective imaging agents for gastrointestinal cancers, and are compelling candidates for further clinical evaluation.

Near-infrared fluorescence imaging using intravenously administered indocyanine green (ICG) improves colorectal liver metastases (CRLM) surgery by enhancing lesion detection and real-time tumor margin assessment. However, ICG accumulates in hepatocytes around CRLM with high variance between patients. This study evaluates the effects of tumor and patient characteristics on ICG accumulation using a standardized imaging and analysis workflow. This single-center study included patients with CRLM who received 10 mg of ICG intravenously 24 h before surgery. Resected lesions were sliced in 5–10-mm-thick sections and immediately imaged for standardized fluorescence analysis. Fluorescence parameters were compared based on chemotherapy treatment, tumor response, tumor size and superficiality, and degree of steatosis. Associations between the patient and tumor characteristics and fluorescence parameters were determined while correcting for confounders. Thirty-two lesions from 32 patients were analyzed. Lesions from chemotherapy-pretreated patients exhibited a lower mean signal fluorescence intensity (MSFI, 0.23 vs. 0.65 a.u.; p = 0.002) and signal-to-background ratio (SBR, 2.28 vs. 6.08; p < 0.001) than lesions from patients without pretreatment. Tumor size correlated positively with MSFI (p = 0.003), SBR (p = 0.02), and maximum intensity (p < 0.001). After correcting for the other characteristics, chemotherapy showed statistically significant association with the fluorescence parameters. The tumor superficiality, degree of steatosis, and response to chemotherapy had no statistically significant associations with the fluorescence parameters. Neoadjuvant chemotherapy significantly lowers ICG accumulation around CRLM resulting in suboptimal contrast. To optimize fluorescence-guided surgery protocols for chemotherapy-pretreated patients, future research should focus on adjusting ICG dose and timing and exploring specific fluorescence tumor-targeting imaging agents.

BackgroundColon cancer is a heterogeneous disease and consists of various molecular subtypes. Despite advances in high-throughput expression profiling, limitations remain in predicting clinical outcome and assigning specific treatment to individual cases. Tumor-immune interactions play a critical role, with tumors that activate the immune system having better outcome for the patient. The localization of T cells within tumor epithelium, to enable direct contact, is essential for antitumor function, but bulk DNA/RNA sequencing data lacks spatial distribution information. In this study, we provide spatial T cell tumor distribution and connect these data with previously determined genomic data in the AC-ICAM colon cancer patient cohort.MethodsColon cancer patients (n=90) with transcriptome data available were selected. We used a custom multiplex immunofluorescence assay on colon tumor tissue sections for quantifying T cell subsets spatial distribution in the tumor microenvironment, in terms of cell number, location, mutual distance, and distance to tumor cells. Statistical analyses included the previously determined Immunologic Constant of Rejection (ICR) transcriptome correlation and patient survival, revealing potential prognostic value in T cell spatial distribution.ResultsT cell phenotypes were characterized and CD3+CD8-FoxP3- T cells were found to be the predominant tumor-infiltrating subtype while CD3+FoxP3+ T cells and CD3+CD8+ T cells showed similar densities. Spatial distribution analysis elucidated that proliferative T cells, characterized by Ki67 expression, and Granzyme B-expressing T cells were predominantly located within the tumor epithelium. We demonstrated an increase in immune cell density and a decrease in the distance of CD3+CD8+ T cells to the nearest tumor cell, in the immune active, ICR High, immune subtypes. Higher densities of stromal CD3+FoxP3+ T cells showed enhanced survival outcomes, and patients exhibited superior clinical benefits when greater spatial distances were observed between CD3+CD8-FoxP3- or CD3+CD8+ T cells and CD3+FoxP3+ T cells.ConclusionOur study’s in-depth analysis of the spatial distribution and densities of major T cell subtypes within the tumor microenvironment has provided valuable information that paves the way for further research into the intricate relationships between immune cells and colon cancer development.

Oral and laryngeal squamous cell carcinoma (OSCC and LSCC) and papillary thyroid carcinoma (PTC) are common head and neck cancers (HNCs) typically treated surgically. Challenges in tumour delineation often lead to inadequate resection margins in OSCC and LSCC, and missed multifocality in PTC. Fluorescence imaging (FLI) using near-infrared tumour-targeting tracers may improve intraoperative identification of malignancy, facilitating precise excision. This study evaluates six potential FLI targets in OSCC, LSCC and PTC. Immunohistochemical staining was performed on OSCC (n = 20), LSCC (n = 10) and PTC (n = 10), assessing CEA, c-Met, EpCAM, EGFR, integrin αvβ6 and VEGF-α. Expression was scored (0–12) using the total immunostaining score (TIS) system, and categorized into absent (TIS 0), low (TIS 1–5), moderate (TIS 6–8) or high (TIS 9–12). Integrin αvβ6 showed significant overexpression in OSCC (TIS: 12; p < 0.001) and LSCC (TIS: 8; p = 0.002), with 80

Surgical intervention for endometriosis is an important treatment modality, yet incomplete resection resulting from poor visibility of affected tissue and consequently recurrence of disease remains a prevalent challenge. Intra-operative visualization of endometriosis, enabling fluorescence-guided surgery (FGS), could help to optimize surgical treatment. A biomarker, upregulated in endometriosis compared to adjacent tissue, is required to use as a target for FGS. Immunohistochemistry was used to evaluate protein expression of a selection of previously identified potential biomarkers. Ten biomarkers were stained in a large cohort of 84 tissues, both deep and peritoneal endometriosis and tissue without endometriosis, all from patients with confirmed endometriosis. MMP11 and VCAN showed the largest upregulation in endometriosis compared to adjacent tissue and showed a membranous or extracellular staining pattern. MMP11 is a promising target for glandular and stromal visualization, VCAN for stromal visualization only. For both biomarkers, upregulation was high in both peritoneal and deep endometriosis and for patients with and without hormonal medication. Other stained biomarkers showed non-beneficial characteristics based on staining pattern or upregulation. Analysis of all endometriosis samples showed that combined glandular and stromal targeting is expected to result in optimal visualization of endometriosis. Further research is needed to determine whether targeting one biomarker is sufficient for this goal, or if dual targeting is necessary. Development of clinical tracers for VCAN and MMP11 is necessary.

Tumor-targeted positron emission tomography (PET) and fluorescence-guided surgery (FGS) could address current challenges in pre- and intraoperative imaging of gastric cancer. Adequate selection of molecular imaging targets remains crucial for successful tumor visualization. This study evaluated the potential of integrin αvβ6, carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5), epidermal growth factor receptor (EGFR), epithelial cell adhesion molecule (EpCAM) and human epidermal growth factor receptor-2 (HER2) for molecular imaging of primary gastric cancer, as well as lymph node and distant metastases. Expression of αvβ6, CEACAM5, EGFR, EpCAM and HER2 was determined using immunohistochemistry in human tissue specimens of primary gastric adenocarcinoma, healthy surrounding stomach, esophageal and duodenal tissue, tumor-positive and tumor-negative lymph nodes, and distant metastases, followed by quantification using the total immunostaining score (TIS). Positive biomarker expression in primary gastric tumors was observed in 86

Despite advances in treatment strategies, colorectal cancer (CRC) continues to cause significant morbidity and mortality, with mounting evidence a close link between immune system dysfunctions issued. Interleukin-2 receptor gamma (IL-2RG) plays a pivotal role as a common subunit receptor in the IL-2 family cytokines and activates the JAK-STAT pathway. This study delves into the role of Interleukin-2 receptor gamma (IL-2RG) within the tumor microenvironment and investigates potential microRNAs (miRNAs) that directly inhibit IL-2RG, aiming to discern their impact on CRC clinical outcomes. Bioinformatics analysis revealed a significant upregulation of IL-2RG mRNA in TCGA-COAD samples and showed strong correlations with the infiltration of various lymphocytes. Single-cell analysis corroborated these findings, highlighting IL-2RG expression in critical immune cell subsets. To explore miRNA involvement in IL-2RG dysregulation, mRNA was isolated from the tumor tissues and lymphocytes of 258 CRC patients and 30 healthy controls, and IL-2RG was cloned into the pcDNA3.1/CT-GFP-TOPO vector. Human embryonic kidney cell lines (HEK-293T) were transfected with this construct. Our research involved a comprehensive analysis of miRPathDB, miRWalk, and Targetscan databases to identify the miRNAs associated with the 3 ' UTR of human IL-2RG. The human microRNA (miRNA) molecules, hsa-miR-7-5p and hsa-miR-26b-5p, have been identified as potent suppressors of IL-2RG expression in CRC patients. Specifically, the downregulation of hsa-miR-7-5p and hsa-miR-26b-5p has been shown to result in the upregulation of IL-2RG mRNA expression in these patients. Prognostic evaluation of IL-2RG, hsa-miR-7-5p, and hsa-miR-26b-5p, using TCGA-COAD data and patient samples, established that higher IL-2RG expression and lower expression of both miRNAs were associated with poorer outcomes. Additionally, this study identified several long non-coding RNAs (LncRNAs), such as ZFAS1, SOX21-AS1, SNHG11, SNHG16, SNHG1, DLX6-AS1, GAS5, SNHG6, and MALAT1, which may act as competing endogenous RNA molecules for IL2RG by sequestering shared hsa-miR-7-5p and hsa-miR-26b-5p. In summary, this investigation underscores the potential utility of IL-2RG, hsa-miR-7-5p, and hsa-miR-26b-5p as serum and tissue biomarkers for predicting CRC patient prognosis while also offering promise as targets for immunotherapy in CRC management.

Significance:Near-infrared fluorescence imaging still lacks a standardized, objective method to evaluate fluorescent dye efficacy in oncological surgical applications. This results in difficulties in translation between preclinical to clinical studies with fluorescent dyes and in the reproduction of results between studies, which in turn hampers further clinical translation of novel fluorescent dyes. Aim:Our aim is to develop and evaluate a semi-automatic standardized method to objectively assess fluorescent signals in resected tissue. Approach:A standardized imaging procedure was designed and quantitative analysis methods were developed to evaluate non-targeted and tumor-targeted fluorescent dyes. The developed analysis methods included manual selection of region of interest (ROI) on white light images, automated fluorescence signal ROI selection, and automatic quantitative image analysis. The proposed analysis method was then compared with a conventional analysis method, where fluorescence signal ROIs were manually selected on fluorescence images. Dice similarity coefficients and intraclass correlation coefficients were calculated to determine the inter- and intraobserver variabilities of the ROI selections and the determined signal- and tumor-to-background ratios. Results:The proposed non-targeted fluorescent dyes analysis method showed statistically significantly improved variabilities after application on indocyanine green specimens. For specimens with the targeted dye SGM-101, the variability of the background ROI selection was statistically significantly improved by implementing the proposed method. Conclusion:Semi-automatic methods for standardized quantitative analysis of fluorescence images were successfully developed and showed promising results to further improve the reproducibility and standardization of clinical studies evaluating fluorescent dyes.

Up to 40 % of breast cancer patients have a tumor-positive resection margin (TPRM) - defined as cancer cells at the surface of the resected specimen - after breast-conserving surgery (BCS), necessitating re-resection or boost radiation. To prevent these additional treatments, intraoperative near-infrared (NIR) fluorescence imaging with the topically applied, cathepsin-activatable imaging agent AKRO-6qcICG might be used to detect TPRMs and guide additional resection. Here, to validate its performance, the agent is topically applied to all surfaces of freshly resected breast cancer specimens (n =11 patients) and to 3-5 mm thick tissue slices of the specimens (n = 26 patients). NIR fluorescence images of the resection surfaces and tissue slices are acquired and correlated to final histopathology. AKRO-6qcICG detects TPRMs with a sensitivity, specificity, PVV, and NPV of 100%, 67%, 10%, and 100%, respectively. On the tissue slices, the fluorescence signal has a median tumor-to-background ratio of 1.8. These findings indicate that topically applied AKRO-6qcICG can visualize TPRMs ex vivo with a high sensitivity and NPV, with sufficient contrast to adjacent healthy breast tissue.

Cysteine cathepsins are proteases that play a role in normal cellular physiology and neoplastic transformation. Elevated expression and enzymatic activity of cathepsins in breast cancer (BCa) indicates their potential as a target for tumor imaging. In particular cathepsin B (CTSB), L (CTSL), and S (CTSS) are used as targets for near-infrared (NIR) fluorescence imaging (FI), a technique that allows real-time intraoperative tumor visualization and resection margin assessment. Therefore, this immunohistochemical study explores CTSB, CTSL, and CTSS expression levels in a large breast cancer patient cohort, to investigate in which BCa patients the use of cathepsin-targeted NIR FI may have added value. Protein expression was analyzed in tumor tissue microarrays (TMA) of BCa patients using immunohistochemistry and quantified as a total immunostaining score (TIS), ranging from 0–12. In total, the tissues of 557 BCa patients were included in the TMA. CTSB, CTSL, and CTSS were successfully scored in respectively 340, 373 and 252 tumors. All tumors showed CTSB, CTSL, and/or CTSS expression to some extent (TIS > 0). CTSB, CTSL, and CTSS expression was scored as high (TIS > 6) in respectively 28

Oesophaegal cancer patients with a clinical complete response (CR) after neoadjuvant chemoradiotherapy (nCRT) are candidates for an active surveillance strategy. Regrowth rates of 40

Supplementary File S4. Reference miRNAs

Fig. S1. Patient selection and omission

Fig. S4. Pathologist scoring of TMAs

The lack of multi-omics cancer datasets with extensive follow-up information hinders the identification of accurate biomarkers of clinical outcome. In this cohort study, we performed comprehensive genomic analyses on fresh-frozen samples from 348 patients affected by primary colon cancer, encompassing RNA, whole-exome, deep T cell receptor and 16S bacterial rRNA gene sequencing on tumor and matched healthy colon tissue, complemented with tumor whole-genome sequencing for further microbiome characterization. A type 1 helper T cell, cytotoxic, gene expression signature, called Immunologic Constant of Rejection, captured the presence of clonally expanded, tumor-enriched T cell clones and outperformed conventional prognostic molecular biomarkers, such as the consensus molecular subtype and the microsatellite instability classifications. Quantification of genetic immunoediting, defined as a lower number of neoantigens than expected, further refined its prognostic value. We identified a microbiome signature, driven by Ruminococcus bromii , associated with a favorable outcome. By combining microbiome signature and Immunologic Constant of Rejection, we developed and validated a composite score (mICRoScore), which identifies a group of patients with excellent survival probability. The publicly available multi-omics dataset provides a resource for better understanding colon cancer biology that could facilitate the discovery of personalized therapeutic approaches.

Contains code to reproduce the image analysis pipeline and the results in the study

Background Hormone receptor (HR)-positive, HER2/neu-negative breast cancers have a sustained risk of recurrence up to 20 years from diagnosis. TEAM (Tamoxifen, Exemestane Adjuvant Multinational) is a large, multi-country, phase III trial that randomized 9776 women for the use of hormonal therapy. Of these 2754 were Dutch patients. The current study aims for the first time to correlate the ten-year clinical outcomes with predictions by CanAssist Breast (CAB)—a prognostic test developed in South East Asia, on a Dutch sub-cohort that participated in the TEAM. The total Dutch TEAM cohort and the current Dutch sub-cohort were almost similar with respect to patient age and tumor anatomical features. Methods Of the 2754 patients from the Netherlands, which are part of the original TEAM trial, 592 patients’ samples were available with Leiden University Medical Center (LUMC). The risk stratification of CAB was correlated with outcomes of patients using logistic regression approaches entailing Kaplan–Meier survival curves, univariate and multivariate cox-regression hazards model. We used hazard ratios (HRs), the cumulative incidence of distant metastasis/death due to breast cancer (DM), and distant recurrence-free interval (DRFi) for assessment. Results Out of 433 patients finally included, the majority, 68.4% had lymph node-positive disease, while only a minority received chemotherapy (20.8%) in addition to endocrine therapy. CAB stratified 67.5% of the total cohort as low-risk [DM = 11.5% (95% CI, 7.6–15.2)] and 32.5% as high-risk [DM = 30.2% (95% CI, 21.9–37.6)] with an HR of 2.90 (95% CI, 1.75–4.80; P < 0.001) at ten years. CAB risk score was an independent prognostic factor in the consideration of clinical parameters in multivariate analysis. At ten years, CAB high-risk had the worst DRFi of 69.8%, CAB low-risk in the exemestane monotherapy arm had the best DRFi of 92.7% [ vs CAB high-risk, HR, 0.21 (95% CI, 0.11–0.43), P < 0.001], and CAB low-risk in the sequential arm had a DRFi of 84.2% [ vs CAB high-risk, HR, 0.48 (95% CI, 0.28–0.82), P = 0.009]. Conclusions Cost-effective CAB is a statistically robust prognostic and predictive tool for ten-year DM for postmenopausal women with HR+/HER2−, early breast cancer. CAB low-risk patients who received exemestane monotherapy had an excellent ten-year DRFi.