Colorectal Cancer Liver Metastases Research Articles

Abstract LB441: An intravenous compatible oncolytic vaccinia virus treated hepatic metastasis of colon cancer through extensive cancer cell killing and activation of cytotoxic effector differentiation

Abstract Colorectal cancer (CRC) is the third most common cancer worldwide and nearly 50% of CRC patients develop liver metastasis during the course of their disease. Treatment of colorectal cancer liver metastasis (CRLM) has been particularly challenging due to tolerogenic nature of liver immune microenvironment as well as an eventual development of therapy resistance to standard chemotherapy regimen. One promising area of cancer immunotherapy is oncolytic virotherapy that can selectively destroy tumor cells and stimulate anti-tumor immune response. In this study, we systemically administered mSJ-650, an intravenous compatible oncolytic Wyeth strain vaccinia virus that expresses human complement regulatory protein CD55 and murine GM-CSF in place of viral thymidine kinase gene and has a deletion of the viral K2L gene, and evaluated its anti-tumor efficacy in CRLM. Mouse CRLM was induced by intrasplenic injection of 5×105 MC38-OVA cancer cells. Following tumor nodules formation in the liver, low dose (1×106 pfu) or high dose (3×106 pfu) of mSJ-650 was administered multiple times via tail vein and liver was harvested for evaluation of anti-tumor efficacy. Flow cytometry analysis was performed to investigate changes in hepatic and tumor immune microenvironment upon mSJ-650 treatment. Liver and tumor tissue were stained for immunofluorescence imaging of viral replication within the tumor cells and subsequent oncolysis by the virus. Systemic administration of mSJ-650 showed potent anti-tumor efficacy and led to significant reduction in metastatic nodule formation in liver even at low dose. The anti-tumor efficacy was mediated by tumor cell-specific viral distribution and replication, followed by lytic egress of mSJ-650 from infected tumor cells. Anti-tumor efficacy of mSJ-650 also accompanied a dramatic shift in immunologically tolerant hepatic microenvironment to immune-stimulatory one by decreasing proportion of myeloid-derived suppressor cells, Kupffer cells, and monocyte-derived macrophages (MDMs) in the liver while increasing CD8+ T cell infiltration by 2~3 folds. Moreover, mSJ-650 treatment was associated with phenotypic change in hepatic immune cells, as evidenced by Kupffer cell and MDM polarization to M1 phenotype and elevated expression of activation markers and cytotoxic molecules in CD8+ T cells. Changes in hepatic immune microenvironment were also observed in tumor nodules, especially in those completely surrounded by adjacent liver tissue, suggesting that anti-tumor immune response in tumor bed is potentiated by reprogramming of tumor-adjacent hepatic immune microenvironment. Systemic administration of mSJ-650 demonstrated superior anti-tumor efficacy in CRLM which was mediated by direct tumor cell killing and tumor-adjacent hepatic immune microenvironment reprogramming by the virus. Citation Format: Eunhye Kim, Yeonsoo Yang, Solchan Won, Namhee Lee, Songyi Lee, Mi-Ju Park, Byung-Jin Jung, Yun-Kyoung Hong, Hang-Rae Kim, Dong-Sup Lee, Keunhee Oh. An intravenous compatible oncolytic vaccinia virus treated hepatic metastasis of colon cancer through extensive cancer cell killing and activation of cytotoxic effector differentiation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB441.

Enhanced Therapeutic Efficacy of the Nanoscale Fluoropyrimidine Polymer CF10 in a Rat Colorectal Cancer Liver Metastasis Model.

Combination chemotherapy regimens that include fluoropyrimidine (FP) drugs, e.g., 5-fluorouracil (5-FU), are central to the treatment of colorectal cancer liver metastases (CRLMs), a major cause of cancer mortality. We tested a second-generation FP polymer, CF10, in a CC531/WAGRij syngeneic orthotopic rat model of liver metastasis to determine if CF10 improved response relative to 5-FU. CF10 displayed increased potency relative to 5-FU in CC531 rat colorectal cancer cells based on clonogenic assay results and caused increased apoptosis, as shown using a live/dead assay. The increased potency of CF10 to CC531 cells was associated with increased replication stress, as assessed by Western blot for biomarkers of ATR/Chk1 and ATM/Chk2 pathway activation. CF10 dosed to deliver equivalent FP content as an established dose of 5-FU in rats (50 mg/kg) did not cause weight loss in WAGRij rats even when combined with ethynyl uracil (EU), an inhibitor of dihydropyrimidine dehydrogenase, the enzyme primarily responsible for 5-FU degradation in the liver. In contrast, 5-FU caused significant weight loss that was exacerbated in combination with EU. Importantly, CF10 was significantly more effective than 5-FU at inhibiting tumor progression (~90% reduction) in the CC531/WAG/Rij CRLM model. Our results reveal strong potential for CF10 to be used for CRLM treatment.

Prognostic factors for overall survival and safety of trans-arterial chemoembolization (TACE) with irinotecan-loaded drug-eluting beads (DEBIRI) in patients with colorectal liver metastases.

Transarterial chemoembolisation with irinotecan-loaded drug-eluting beads (DEBIRI TACE) can be considered in patients with unresectable colorectal cancer liver metastases (CRLM) who progress after all approved standard therapies or in patients unsuitable for systemic therapy. Between September 2010 and March 2020, thirty patients (22 men and 8 women; mean age 66.8 ± 13.2) were included in this retrospective study. DEBIRI TACE was conducted in 43% of patients unsuitable for systemic therapy as a first-line treatment and 57% as salvage therapy after the progression of systemic therapy. All the patients had liver-limited disease. In the case of unilobar disease, two treatments were performed at four-week intervals, and in the case of bilobar disease, four treatments were performed at two-week intervals. All patients were premedicated and monitored after the procedure. Adverse events were graded according to the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) classification system for complications. The median overall survival (OS) from the beginning of DEBIRI TACE in the salvage group was 17.4 months; in the group without prior systemic therapy, it was 21.6 months. The median overall survival of all patients was 17.4 months (95% confidence interval [CI]: 10.0-24.7 months), and progression-free survival (PFS) was 4.2 months (95% CI: 0.9-7.4 months). The one-year survival rate after the procedure was 61%, and the two-year rate was 25%. Univariate analysis showed better survival of patients with four or fewer liver metastases (p = 0.002). There were no treatment-related deaths or grade 4 and 5 adverse events. Nonserious adverse events (Grades 1 and 2) were present in 53% of patients, and Grade 3 adverse events were present in 6% of the patients. DEBIRI TACE is a well-tolerated treatment option for patients with liver metastases of colorectal cancer. Patients with four or fewer liver metastases correlated with better survival.

Fusobacteria alterations are associated with colorectal cancer liver metastasis and a poor prognosis.

Liver metastasis is a major cause of mortality in patients with advanced stages of colorectal cancer (CRC). The gut microbiota has been demonstrated to influence the progression of liver diseases, potentially providing novel perspectives for diagnosis, treatment and research. However, the gut microbial characteristics in CRC with liver metastasis (LM) and with no liver metastasis (NLM) have not yet been fully established. In the present study, high-throughput 16S RNA sequencing technology was employed, in order to examine the gut microbial richness and composition in patients with CRC with LM or NLM. A discovery cohort (cohort 2; LM=18; NLM=36) and a validation cohort (cohort 3; LM=13; NLM=41) were established using fresh feces. In addition, primary carcinoma tissue samples were also analyzed (LM=8 and NLM=10) as a supplementary discovery cohort (cohort 1). The findings of the present study indicated that the intestinal microbiota richness and diversity were increased in the LM group as compared to the NLM group. A significant difference was observed in species composition between the LM and NLM group. In the two discovery cohorts with two different samples, the dominant phyla were consistent, but varied at lower taxonomic levels. Phylum Fusobacteria presented consistent and significant enrichment in LM group in both discovery cohorts. Furthermore, with the application of a random forest model and receiver operator characteristic curve analysis, Fusobacteria was identified as a potential biomarker for LM. Moreover, Fusobacteria was also a poor prognosis factor for survival. Importantly, the findings were reconfirmed in the validation cohort. On the whole, the findings of the present study demonstrated that CRC with LM and NLM exhibit distinct gut microbiota characteristics. Fusobacteria detection thus has potential for use in predicting LM and a poor prognosis of patients with CRC.

Extracellular volume fraction can predict the treatment response and survival outcome of colorectal cancer liver metastases

ObjectiveTo assess the prognostic value of pre- and post-therapeutic changes in extracellular volume (ECV) fraction of liver metastases (LMs) for treatment response (TR) and survival outcomes in colorectal cancer liver metastases (CRLM). Methods186 LMs were confirmed by pathology or follow-up (Training: 130; Test: 56). We analyzed the changes in ECV fraction of LMs before and after 2 cycles of chemotherapy combined with bevacizumab. After 12 cycles, we evaluated the TR on LMs based on the RECIST v1.1. Relative changes in ECV fraction and Hounsfield Units (HU), defined as ΔECV and ΔHU, were associated with progression-free survival (PFS), overall survival (OS), and TR. We identified TR predictors with multivariate logistic regression and PFS, OS risk factors with COX analysis. Results186 LMs were classified as TR lesions (TR+: 84) and non-TR lesions (TR-:102). ΔECV, ΔHUA-E, and texture could distinguish the TR of LMs in training and test set (P < 0.05). ΔECV [Odds ratio (OR): 1.03; 95% Confidence interval (CI): 1.02–1.05, P < 0.01] was an independent predictor of TR-. Area under the curve (AUC), sensitivity and specificity of TR model in training and test set were 0.87, 0.84, 90.14%, 90.32%, 72.88%, 64.00%, respectively. High CRD_score indicates that patients have shorter PFS [Hazard ratio (HR): 2.01; 95%CI: 1.02–3.98, P = 0.045)] and OS (HR: 1.89, 95%CI: 1.04–3.42, P = 0.038). ConclusionΔECV can be used as an independent predictor of TR of CRLM chemotherapy combined with bevacizumab.

Abstract 5520: β2 adrenergic receptor signaling promotes colorectal cancer liver metastasis

Abstract Liver is the most common site for cancer metastases, which may be attributed to the hepatic immunosuppressive microenvironment. Recent studies have highlighted the immunomodulatory and tumor-supportive roles of neurotransmitter-receptor signals in various cancers. Given that various neurotransmitter receptors are expressed in the liver, we aimed to investigate their possible involvement in the metastatic-prone liver microenvironment. Single-cell RNA sequencing analysis identified ADRB2, which encodes β2-adrenergic receptor (β2-AR), as the top-upregulated neurotransmitter receptor gene in colorectal cancer (CRC) and liver metastasis in patients with CRC liver metastasis (CRLM). Co-immunofluorescence (co-IF) staining confirmed the colocalization of β2-AR with myeloid cell marker CD11b instead of T cell marker CD3 and NK cell marker CD56 in patients with CRLM. Consistently, we observed the upregulation of CD11b/β2-AR double-positive cells in the liver tissues from mice bearing CRC or CRLM compared to naïve mice through co-IF staining. High-dimensional flow cytometry analysis further revealed that β2-AR was mainly expressed in macrophages and myeloid-derived suppressor cells (MDSCs). Treatment of CRC-tumor bearing mice with pan β-AR inhibitor propranolol and β2-AR specific inhibitor showed a potential to reduce liver metastatic incidence without suppressing primary CRC. Mechanistically, β2-AR activation may upregulate the expression of S100a8/9 to enhance the immunosuppressive activity of macrophages and MDSCs, thereby promoting CRC liver metastasis. Taken together, our findings reveal the potential of targeting β2-AR signaling for the prevention and treatment of liver metastasis. This project is supported by the Hong Kong University Grants Committee through the General Research Fund (14104820, 14107622, 24110323) and the Strategic Seed Funding for Collaborative Research Scheme (SSFCRS) from the Chinese University of Hong Kong. Conflict of interest: The authors declare no conflict of interest. Citation Format: Yixuan Zhang, Jintian Chen, Thomas Ting Hei Chan, Huanyu Wang, Jiahuan Lu, Jingqing Li, Jingying Zhou. β2 adrenergic receptor signaling promotes colorectal cancer liver metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5520.

Abstract 3082: The liver microenvironment promotes glycolysis in metastatic colorectal cancer by activating her3

Abstract Background: Liver metastasis occurs in ~80% of all metastatic colorectal cancer (mCRC) and the liver has a unique endothelial cell (EC)-rich microenvironment that promotes cancer cell survival. We previously reported that liver ECs secrete soluble factors to promote CRC growth via activating CRC-associated the HER3 signaling pathway. The present study reports that ECs promote mCRC growth by shifting cancer metabolism towards glycolysis and elucidates the involved signaling pathway. Methods: We performed mass spectrometry to profile the metabolic changes in mCRC treated with/without HER3 inhibition in a syngeneic, orthotopic mCRC model. We also performed Seahorse and lactate ELISA assays to determine the effect of liver EC-secreted factors on CRC metabolism. To further determine the role of HER3 in promoting glycolysis and CRC growth in the liver, we used siRNA silencing of HER3 and pharmacological inhibition of HER3 downstream signaling proteins to identify the key mediator(s) of HER3-induced metabolic shift in CRC. Results: We determined that HER3 inhibition leads to increased oxidative phosphorylation metabolites (OXPHOS) and decreased glycolysis metabolites in CRC liver metastases. Conditioned medium containing EC-secreted factors decreased oxygen consumption (determined by Seahorse, a readout of OXPHOS) and increased lactate secretion (determined by ELISA, a readout of glycolysis) in CRC. As HER3 inhibition reversed the metabolic shift and increased OXPHOS as an alternative survival strategy, we found that simultaneous inhibition of HER3 and OXPHOS synergistically blocked CRC cell and tumor growth. Lastly, we found that PFK2 is activated by HER3 signaling, determined by phosphorylation, and determined that the HER3-AKT-PFK2 signaling axis is the key mediator of EC-induced metabolic shifts. Conclusions: We identified that the liver microenvironment activates HER3 and the downstream AKT-PFK2 signaling to promote glycolysis and growth in CRC liver metastases by activating AKT-PFK2-dependent glycolysis. Our findings highlighted the potential of combining HER3 and OXPHOS inhibitions as a potential strategy for treating patients with mCRC. Citation Format: Moeez Ghani Rathore, Kimberly Curry, Christina Boutros, Zhenghe Wang, Jordan Winter, Rui Wang. The liver microenvironment promotes glycolysis in metastatic colorectal cancer by activating her3 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3082.

Abstract 906: Large-scale surface protein abundance prediction from single-cell transcriptomes with a zero-shot model and its applications to cancer research

Abstract We develop SPIDER, a zero-shot model which can predict the abundance for a large scale (&amp;gt;2,000) of surface proteins from single-cell transcriptomes in various contexts. This is to overcome the challenges in current single-cell protein abundance quantification tools (e.g., flow cytometry, CITE-seq) and computational models (e.g., totalVI, Seurat, cTPnet), where routinely only &amp;lt;300 surface proteins can be quantified or predicted. Comprehensive benchmarking on four external validation sets shows that the prediction accuracy of SPIDER outperforms other state-of-the-art methods including Seurat, totalVI, and cTPnet, with a prediction accuracy elevated as much as 42.5% in new contexts. We further conduct case studies in cancers by applying SPIDER to predict the abundance of &amp;gt;2,500 surface proteins on scRNA-seq datasets of hepatocellular carcinoma (HCC) and colorectal cancer liver metastasis (RCRLM), where the predicted surface protein abundance data is analyzed to demonstrate the broad downstream applications of SPIDER including facilitating cell type annotation, disease biomarker/target identification, and cell-cell interaction (CCI) inference. For instance, in these datasets we find that SPIDER can reveal (novel) disease biomarkers that are overlooked by solely observing transcript expression, such as CD44/PIK3IP1 in hepatocytes/γδ2 T cells as a positive/negative HCC biomarker, demonstrating the capability of SPIDER to compensate for the limitations in the RNA modality. In conclusion, we propose the SPIDER model which can provide valuable information on the abundance of a large scale of surfaceomes in single cells, and can be further used to gain new insights into cancers via promoting cell type annotation, disease biomarker/target identification, and CCI inference. Citation Format: Ruoqiao Chen, Bin Chen, Jiayu Zhou. Large-scale surface protein abundance prediction from single-cell transcriptomes with a zero-shot model and its applications to cancer research [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 906.

Abstract 2961: Investigating the role of aging and treatment-induced senescence in the metastatic liver cancer tumor microenvironment

Abstract Liver senescence, marked by the progressive decline in hepatic cell function and regenerative capacity, plays a vital role in the context of aging, chronic liver diseases, and cancer progression, particularly when influenced by anti-cancer therapies. This study is designed to extensively characterize liver senescence under two specific conditions: replicative aging and therapy-induced changes. We examined liver samples from 20 individuals, covering a wide age range (young, &amp;lt;40 years; old, &amp;gt;60 years), and 16 cases of colorectal cancer (CRC) liver metastasis (ages 37-66). Our integrative approach melds single-nucleus RNA-sequencing (snRNA-seq) and ATAC-sequencing (snATAC-seq) to investigate the transcriptomic and epigenetic landscapes across a spectrum of liver cell types, including hepatocytes, cholangiocytes, stellate cells, liver sinusoidal endothelial cells, and diverse immune cells. Key findings include an upregulation of senescence markers such as CDKN1A, CDKN2A, and HMGB1, particularly in specific hepatocytes from older individuals and various cell types in the CRC liver metastasis group. Furthermore, we noted a distinctive senescence-associated secretory phenotype (SASP) across multiple immune cell types in our treated CRC liver metastasis group and upregulation of treatment-induced senescence gene signatures, such as SenCan. Moreover, hepatic stellate cells from older subjects exhibited augmented senescence-related gene signatures (SenSig) and transcription factors (SenMayo), with myofibroblast-like and FAP+ stellate cells showing a marked senescence phenotype, evidenced by elevated SASP molecule expression (CCL2, SERPINE1, GLB1, IGFBP7, IGFBP3).Incorporating advanced high-resolution imaging techniques, our study delves into the detailed morphological characteristics and spatial distribution of senescence markers within the liver in the setting of replicative aging and treatment-induced senescence. This study sheds light on the heterogeneity and intricacies of senescence-associated gene expression within liver cell populations. By combining comprehensive multiomic data with advanced high-resolution spatial profiling, we aim to decipher unique senescence phenotypes in the context of both replicative and treatment-induced senescence. Our work highlights the significance of cellular senescence in liver pathologies and cancer progression, suggesting new directions for therapeutic interventions that target these complex dynamics. Citation Format: Kelsey Gallant, Alla Karpova, Xiang Li, Michael Iglesia, Andrew Houston, Daniel Rapp, Chien-Wei Peng, Clara Liu, John Herdon, Feng Chen, Ryan Fields, Li Ding. Investigating the role of aging and treatment-induced senescence in the metastatic liver cancer tumor microenvironment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2961.

Abstract 7635: Orion™: 14-plex clinical sample imaging of liver cancer modalities using one-step staining and imaging

Abstract Background To better understand the complexities of the tumor microenvironment (TME), high-resolution imaging at a sub-cellular resolution and high-plex is needed. These serve as a basis for biomarker quantification and more downstream, may provide the ability to predict patient outcome. Here, we investigate three whole slide liver sections: fetal liver, hepatocellular carcinoma (HCC), and colorectal cancer (CRC) liver metastasis. Methods 5-micron sections were cut and mounted on Superfrost Plus slides prior to de-paraffinization and antigen retrieval using the BioGenex EZ-Retriever system. Autofluorescence was quenched using UV and white light and blocked with Image-iT™ FX Signal Enhancer. Whole slides were stained with the 14-plex antibody panel, coverslip mounted with ArgoFluor™ Mounting Medium and cured overnight. Whole slides were imaged at 20X using the Orion™ spatial biology platform. Coverslips were removed in aqueous solution prior to H&amp;E staining and scanning. Results Sample specific differences were observed, likely stemming from the different tissue sources. Data revealed a distinction between hepatocytes highlighted in the autofluorescence channel, sinusoids filled with proliferating progenitor cell and macrophages, and epithelial cells lining the border of the fetal liver forming the ductal plate surrounding the portal vein. Whereas in HCC, imaging revealed autofluorescent hepatocytes obliterating the sinusoids with some hepatocytes dividing, an extensive capillary network, and red bloods cells also highlighted in the auto fluorescent channel. T cells and macrophages showed clustering within the capillary networks and as expected, hepatocytes expressed high levels of Albumin. In the CRC liver metastasis sample, hepatocytes were shown to be surrounded by T cells, neoplastic glands (PanCK), and CD163+FOLR2+ macrophages. Furthermore, the majority of the metastatic epithelial cancer cells were observed to be proliferating. Conclusions We were able to observe precise differences in the tissue architecture of liver samples from three divergent sources. Specifically, the ability to identify distinct cell subtypes and their spatial co-localization may provide mechanistic insights into the spatial immune landscape and its role in disease progression and treatment outcome. This exemplifies the need for dissecting the spatial heterogeneity of the TME using a technology that offers a high-resolution subcellular snapshot in time; exhibiting the potential for Orion to bridge the gap from bench-to-bedside. Citation Format: Selena Larkin, Jennifer Currenti, Rhea Pai, Soumi Chatterjee, Archita Mishra, Jacob George, Brady Gardner, Ankur Sharma. Orion™: 14-plex clinical sample imaging of liver cancer modalities using one-step staining and imaging [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7635.

Abstract 7417: SpatialCS: A tool to effectively integrate histological annotations and spatial transcriptomics analysis

Abstract Spatial transcriptomics is revolutionizing our understanding of tumor ecosystems, providing insights into the spatial dimensions of cell locations, their organization, and interactions within tissues. A key challenge in this field is integrating histological annotations with spatial domains identified through unsupervised clustering methods like SpaGCN. This integration is crucial for accurate spatial domain identification and further analyses. However, clustering results often vary based on parameters such as resolution, leading to inconsistencies with histological annotations. This variation necessitates optimized parameter selection to achieve the best clustering outcomes. We here introduce SpatialCS, a novel tool specifically designed to both visualize and quantify the alignment between histological annotations and the clustering results obtained from spatial transcriptomics data. SpatialCS employs a new index based on the asymmetric Wallace indices. This index penalizes spot pairs that are clustered together but do not share the same histology annotation type, with penalties scaled according to their transcriptional similarity. Additionally, we propose a purity index, derived by calculating the average transcriptional entropy of all clusters. This index serves as a measure of the homogeneity within each cluster. Furthermore, SpatialCS includes a unique visualization function. This function projects histological annotations onto the clustering results as outlines, making it easier to assess the consistency between histology annotations and clustering outcomes. We have applied SpatialCS to Visium spatial transcriptomics data generated on four colorectal cancer liver metastases, each accompanied by comprehensive spot-level histological annotations in both tumor and normal compartments. The histologic annotations include but not limited to are tumor cells, tumor cell cluster subtypes, tumor stroma, tumor in the vessels, portal tract, individual bile ducts, portal vein and liver cell plates and non-neoplastic stroma. The application of SpatialCS has proven its effectiveness in identifying the most consistent clustering results, which were further confirmed by experienced pathologists. Notably, the output of SpatialCS offers helpful guidance for improving histological annotations. Together, SpatialCS not only provides a quantitative approach to evaluate the consistency between histological annotations and unsupervised clustering analysis but also showcases its potential to significantly enhance histological annotations. Citation Format: Yanshuo Chu, Kyung Serk Cho, Isha Khanduri, Tieling Zhou, Jiahui Jiang, Yunhe Liu, Xinmiao Yan, Guangsheng Pei, Yibo Dai, Yang Liu, Ruiping Wang, Akshaya S Jadhav, Sharia Hernandez, Humam Kadara, Luisa Maren Solis Soto, Scott Kopetz, Dipen Maheshbhai Maru, Linghua Wang. SpatialCS: A tool to effectively integrate histological annotations and spatial transcriptomics analysis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7417.

Abstract 1385: Crosstalk between hepatocyte and myeloid-specific IL17 signaling in colorectal cancer metastasis

Abstract Advanced colorectal cancer (CRC) is resistant to current immunotherapies and prone to metastasis. Chronic inflammation mediated by cytokines such as interleukin (IL)17 activates the oncogenic pathways in cancer cells, promoting sporadic and inflammation-associated CRC. Increased levels of IL17A in early stages of CRC portends poor prognosis indicating its potential involvement into metastasis. We and others previously showed that IL17A signaling is required for early CRC tumorigenicity in a variety of models and that in early CRC, its ability to signal to epithelial cells is essential. What remains unknown is whether IL17 signaling to other cell types within the tumor microenvironment (TME) is essential to control tumor progression and metastasis. Using a model of colitis-associated cancer (CAC) we found that “late” IL17A neutralization decreases tumor burden, possibly acting through regulation of myeloid cells and chemokine network essential for the control of immunosuppressive TME. Next, using models of colorectal cancer liver metastasis (CRLM) including intraportal cell injection and cecum transplantation of organoids with distinct set of oncogenic mutation we found that IL17 neutralization reduces metastasis. FACS analysis revealed that IL17A promotes the recruitment of tumor-associated macrophages and other key myeloid subsets into the metastatic liver environment. Interestingly, ablation of IL17RC (receptor) in myeloid cells only (using Il17rcf/f -LysMCre mice) led to reduction in metastasis and reshaping of metastatic myeloid cell compartments. Meanwhile, IL17 signaling in hepatocytes was required for early metastasis and pre-metastatic niche formation, as the ablation of IL17RC in hepatocytes (using Il17rcf/f -AlbCre mice) led to a reduction of metastatic numbers but not growth. This coincided with reduced neutrophil recruitment and enhanced activation of cytotoxic innate lymphoid cells and CD8 T lymphocytes, indicating the role of hepatocyte specific IL17 signaling in blunting anti-tumor immunity. Our findings illuminate the role of inflammatory cytokine IL17 into CRC progression and metastasis and imply its distinct cell type specific role within the metastatic liver TME. Citation Format: Katarzyna Chojnacka, Dan Kamen, Katrina M. Reyes, Hana Tomizawa, Sergei I. Grivennikov. Crosstalk between hepatocyte and myeloid-specific IL17 signaling in colorectal cancer metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1385.

Abstract 770: The innate immune system response to malignancy- under the radar

Abstract It has become clear that many cancers evade detection by, for example, silencing of immune checkpoints. Re-activation of the immune armamentarium by checkpoint inhibitors has improved survival in many types of cancer. However, we still are unable to gauge the response of the innate immune system (InImS) to incipient malignancy. The InImS is likely both a sentient early warning system and an immediately deployed cancer combatant. We describe a potential marker that quantifies the innate immune system response to multiple deadly tumors. Methods: We obtained a database of patients at high risk of colorectal neoplasia and prospectively noted those who contracted cancer on follow up. We contrasted the historic, premorbid biomarker response from the time of enrolment, primarily using the FERAD ratio. This was obtained by dividing the ferritin blood concentration by the denominator of fecal shedding of a Paneth cell marker, p87. We also compared the FERAD response to the absolute neutrophil:lymphocyte ratio (NLR), a known prognostic biomarker, and also the available, known PDL-1 response for each group of cancers. Results: We found that certain groups of cancers historically had very low FERAD ratios while others were high. Using FERAD ratios for lung, gastric, non-Hodgkin’s lymphoma, melanoma, thyroid, renal, and head and neck cancers, there is a significant inverse correlation between survival and FERAD (r=-0.8;p&amp;lt;0.025) which is similar to that of NLR (r=-0.7;p&amp;lt;0.035). For prostate cancer, breast, colorectal cancer (CRC), leukemia/MDS, there is a direct correlation between survival and FERAD (r=0.99;p&amp;lt;0.002). There is also an inverse relationship between NLR and PDL-1 response rates (r=-0.8;p&amp;lt;0.04). An observed mild positive trend for FERAD PDL-1 response rates may bode well for melanoma, lung, head and neck and renal cancers. Conclusions: Since p87 could be manipulated by dietary means to affect the FERAD ratio favorably, this could be incorporated into more effective chemotherapy regimens and result in better cancer treatment outcomes. Hepatocellular cancer (HCC) and CRC-liver metastasis appear to be immunological outliers. This will need an additional unique approach such as TIGIT intervention therapy (Zheng et al.. Immune checkpoint targeting TIGIT in HCC. Am J Transl Res. 2020). This may allow modulation of the immune response based on FERAD, NLR ratios, and other considerations of mutational burden and genetic mutations, in patients with selected cancers. Citation Format: Martin Tobi, Harvinder Talwar, Benita McVicker. The innate immune system response to malignancy- under the radar [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 770.

Abstract 3994: N glycosylation inhibition hinders immunosuppressive tumor microenvironment cells improving CAR T cell efficacy

Abstract Adoptive transfer of CAR T cells demonstrated impressive results against B-cell malignancies, but still limited efficacy against solid tumors. In this context, multiple challenges need to be overcome, including poor tumor recognition and strong immunosuppression within the tumor microenvironment (TME). Our Unit has recently reported that pharmacological inhibition of N-glycan synthesis in cancer cells increases CAR T cell efficacy by improving tumor recognition and preventing T cell exhaustion. In this project, we investigated the role of N-glycosylation blockade on TME cells in the context of colorectal cancer (CRC) and pancreatic adenocarcinoma (PDAC)-derived liver metastases, exploiting CEA-specific CAR T cell therapy. To understand the effect of N-glycosylation blockade on TME cells (both M2-like macrophages, M2-M and Hepatic stellate cells, HepSCs), we analyzed the phenotypic and transcriptional profile and we performed in vitro functional assays, such as tripartite co-cultures, suppressive assays and released-cytokines analysis. In vitro studies revealed that N-glycosylation inhibition abolishes the ability of both TME cells to restrain T cell proliferation and increases the elimination of cancer cell lines and patient-derived tumor organoids (PDOs from CRC-liver metastases). Interestingly, these effects were associated with profound phenotypic and transcriptional changes in M2-M and HepSCs. In particular, the treatment was able to inhibit M2-polarization in terms of surface markers expression, IL-10 secretion and gene expression profile, and was shown to hinder the activation of HepSCs. Moreover, to evaluate the effect of N-glycosylation inhibition on TME cells in vivo, we exploited immunodeficient mice reconstituted with a human immune system (huSGM3), engrafted intra-liver with tumor cells and treated with CEA CAR T cells. Interestingly, in this in vivo model, the presence of human immune cells supports CAR T cell responses and helps recreate an immune TME more representative of the human disease. Importantly, using these mice we observed that N-glycosylation inhibition improves CEA CAR T cells fitness, enhancing their antitumor activity in terms of survival. This effect is associated with a modulation of human immune TME populations and in particular with the downregulation of immunosuppressive genes in tumor-infiltrating human immune cells (from scRNAseq and Nanostring analysis). Overall, these data suggest that blocking N-glycosylation can help overcome multiple barriers that currently limit CAR T cell efficacy in solid tumors, acting not only on tumor cells, but also on immunosuppressive tumor microenvironment cells. Citation Format: Camilla Sirini, Beatrice Greco, Chiara Balestrieri, Barbara Camisa, Laura Falcone, Rita El Khoury, Oronzina Botrugno, Giulio Giovannoni, Giovanni Tonon, Emanuela Brunetto, Maria Giulia Cangi, Federica Pedica, Alice Bergamini, Fabio Ciceri, Chiara Bonini, Monica Casucci. N glycosylation inhibition hinders immunosuppressive tumor microenvironment cells improving CAR T cell efficacy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3994.

Abstract 925: Continuing anti-EGFR treatment prolonged survival in mCRC patients receiving conversion liver resection

Abstract Introduction: Anti-EGFR monoclonal antibody plus doublet chemotherapy is the mainstay of first-line treatment of RAS/BRAF wild-type metastatic colorectal cancer (mCRC) patients. Some of these patients might undergo secondary resection. However, there is no standardized suggestion on whether colorectal cancer liver metastasis patients should keep target therapy after secondary resection. NCCN guidelines suggest chemotherapy only in patients receiving primary liver resection. Whether we could spare the use of target therapy after secondary resection is the main aim of our study. Methods: Using Taiwan's National Health Insurance Research Database, we established a cohort of KRAS wild-type mCRC patients treated with first-line anti-EGFR therapy plus doublet chemotherapy between 2013 and 2018. Secondary surgery was defined as either resection of liver metastases or radiofrequency ablation. Results: 5694 stage IV mCRC patients received anti-EGFR MAb plus doublet chemotherapy as a first-line treatment between 2013 and 2018. 174 patients were enrolled in the final analysis, with 153 continuing anti-EGFR MAb after secondary resection and 21 patients without anti-EGFR MAb. Compared with those who without anti-EGFR therapy after secondary resection, patients who continued anti-EGFR MAb exhibited significantly longer overall survival (OS; median, 43.8 vs. 31.9 months, p = 0.031) but not in time to treatment failure (TTF; median, 22.2 vs. 26.6 months, p = 0.841). The OS benefits of continuing anti-EGFR MAb remained regardless of left-sided or right-sided primary tumors (40.9 vs. 43.0 months, p = 0.980). The patient cohort from 2016 to 2018 showed more prolonged survival than from 2012 to 2015 (not reached vs. 40.450, p = 0.0305). TTF has no statistical difference when considering patient cohort or primary tumor location. In multivariate analyses, continuing first-line anti-EGFR MAb therapy after secondary resection remained an independent predictor of longer OS. Conclusion: For mCRC patients who received secondary resection after first-line anti-EGFR and doublet chemotherapy, continuing anti-EGFR MAb after resection was associated with significantly longer OS regardless of primary tumor sidedness. Citation Format: Yao-Yu Hsieh, Chin-Wen Tsai, T-CARE Group, Yi-Hsieh Liang. Continuing anti-EGFR treatment prolonged survival in mCRC patients receiving conversion liver resection [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 925.

Abstract 1160: Investigating spatial gene expression profiling in colorectal cancer: Tumor and stroma comparison between primary lesions and matched liver metastases

Abstract The nanoString GeoMx® Digital Spatial Profiling (DSP) enables the investigation of spatial assessment of tumors through high-plex profiling at the RNA and protein levels. Recent genomic analyses have revealed the intertumor heterogeneity between primary and metastatic lesions in colorectal cancer (CRC) patients. In CRC with liver metastases, current treatment strategies are mainly based on the parameters of primary tumors, and metastatic heterogeneity is a challenge since molecular heterogeneity contributes to therapeutic resistance. Furthermore, spatial intratumor heterogeneity exists within a single tumor between cancer cells (tumor) and their microenvironment (stroma) in human cancers. However, whether there are distinct spatial gene expression patterns of tumor and stroma between primary lesions and liver metastases remains unclear in CRCs. We examined 24 formalin-fixed paraffin-embedded tissue samples, including primary lesions and matched liver metastases from 12 patients (6 with synchronous and 6 with metachronous metastases) using NanoString GeoMx® DSP. The best regions of interest (ROI) with the invasive front boundary of the tumor were selected by pathologists. The ROI was segmented into PanCK-positive (tumor) and PanCK-negative (stroma), followed by a collection of indexed oligonucleotides and sequencing on Illumina instrument. Differential expression and pathways enrichment analyses were performed using R BioConductor package standR, limma, and GSEABase. Statistical significances were based on |Log2 fold change| &amp;gt; 1 and Benjamini-Hochberg-corrected P &amp;lt; 0.05. Immune cell abundance was estimated using the SpatialDecon package. In 12 metastatic patients (mean age, 61 years ± 7 [standard deviation]), liver metastatic stroma was associated with 68 upregulated and 93 downregulated genes compared to the primary stroma, with enrichment of 'Immune response' terms in gene set enrichment analysis (GSEA). A higher proportion of CD4 T memory cells and increased expression of cytotoxic genes (IL7R [2.02-fold], CD3E [1.75-fold], KLRB1 [1.68-fold], and GZMK [1.54-fold]) were observed in liver stroma compared to primary stroma. Conversely, liver metastatic tumors were associated only with 23 upregulated and 6 downregulated genes compared to primary tumors, with 'humoral response' terms enriched in GSEA. Similar patterns were observed in stratified analyses with synchronous and metachronous metastases, although a more prominent ‘immune response’ was observed in synchronous metastatic stroma compared to the primary stroma. We revealed that higher immune cell proportion and cytotoxic activity were observed in liver metastatic stroma compared to CRC stroma, providing novel insights into a unique etiology and may yield clinical implications for developing targeted treatment modalities for liver metastatic CRC patients. Citation Format: Jongwon Lee, Yeseul Kim, Hyo Seon Ryu, Jongmin Sim, Chungyeul Kim, Jong Min Park, Ah-Reum Lim, Jung Sun Kim, Hwa Jung Sung, Xingyi Guo, Jungmin Choi, Jungyoon Choi. Investigating spatial gene expression profiling in colorectal cancer: Tumor and stroma comparison between primary lesions and matched liver metastases [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1160.

Reduced chemokine C-C motif ligand 1 expression may negatively regulate colorectal cancer progression at liver metastatic sites.

Colorectal cancer (CRC) liver metastasis, albeit a stage-IV disease, is completely curable by surgical resection in selected patients. In addressing the molecular basics of this phenomenon, differentially expressed genes at primary and liver metastatic sites were screened by RNA sequencing with the use of paraffin-embedded surgical specimens. Chemokine C-C motif ligand 1 (CCL1), a chemotactic factor for a ligand of the chemokine C-C motif receptor 8 (CCR8), was isolated as one of the differentially expressed genes. Histological analysis revealed that the number of CCL1-positive cells, mainly tumour associated macrophages (TAMs) located in the stroma of CRC, decreased significantly at liver metastatic sites, while the expression level of CCR8 on CRC remained unchanged. To explore the biological significance of the CCL1-CCR8 axis in CRC, CCR8-positive CRC cell line Colo320DM was used to assess the effect of the CCL1-CCR8 axis on major signalling pathways, epithelial mesenchymal transition induction and cell motility. Upon stimulation of recombinant CCL1 (rCCL1), phosphorylation of AKT was observed in Colo320DM cells; on the other hand, the corresponding significant increase in MMP-2 levels demonstrated by RT-qPCR was nullified by siRNA (siCCR8). In the scratch test, rCCL1 treatment significantly increased the motility of Colo320DM cells, which was similarly nullified by siCCR8. Thus, the activation of the CCL1-CCR8 axis is a positive regulator of CRC tumour progression. Reduced CCL1 expression of TAMs at liver metastatic sites may partly explain the unique slow tumour progression of CRC, thus providing for a grace period for radical resection of metastatic lesions.

Non-Alcoholic Fatty Liver Disease May Be a Risk Factor for Liver Metastasis After Radical Surgery for Colorectal Cancer: A Retrospective Study.

Distant metastasis develops in approximately one-third of patients with colorectal cancer (CRC) who undergo radical surgery, and colorectal liver metastasis (CRLM) is the most common form of distant metastasis in CRC. Hepatectomy is the only potentially curative treatment for CRLM, but few patients with metastatic CRC meet the criteria for this radical resection, and the 5-year survival rate is poor. Identifying risk factors for CRLM is critical. Non-alcoholic fatty liver disease (NAFLD) is an independent risk factor for CRC. However, the effect of NAFLD on CRC liver metastasis after radical surgery remains unclear. Therefore, we examined the impact of NAFLD-associated hepatic fibrosis on liver metastasis after radical surgery for CRC. We retrospectively analyzed data from 388 patients who underwent curative surgery for CRC at our hospital between April 2008 and March 2015. The patients' clinical results, surgical procedures, postoperative course, and pathological and survival data were collected from the hospital records. The NAFLD fibrosis score was calculated and used to divide the patients into two groups (NAFLD and non-NAFLD). Recurrence was observed in 83/388 (21.4%) patients after a mean follow-up of 65.6 ± 15.1months. Twenty-five patients had liver metastasis: 8 in the NAFLD group (8/45; 17.8%) and 17 in the non-NALFD group (17/343; 5.0%) (p = 0.004). Liver metastasis-free survival was significantly worse in the NAFLD than non-NAFLD group (p < 0.001). NAFLD and cancer stage were independent risk factors for liver metastasis recurrence. NAFLD may be a risk factor for liver metastasis in patients with CRC who undergo curative surgery.

Use of tryptic peptide MALDI mass spectrometry imaging to identify the spatial proteomic landscape of colorectal cancer liver metastases.

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths worldwide. CRC liver metastases (CRLM) are often resistant to conventional treatments, with high rates of recurrence. Therefore, it is crucial to identify biomarkers for CRLM patients that predict cancer progression. This study utilised matrix-assisted laser desorption/ionisation mass spectrometry imaging (MALDI-MSI) in combination with liquid chromatography-tandem mass spectrometry (LC-MS/MS) to spatially map the CRLM tumour proteome. CRLM tissue microarrays (TMAs) of 84 patients were analysed using tryptic peptide MALDI-MSI to spatially monitor peptide abundances across CRLM tissues. Abundance of peptides was compared between tumour vs stroma, male vs female and across three groups of patients based on overall survival (0-3 years, 4-6 years, and 7+ years). Peptides were then characterised and matched using LC-MS/MS. A total of 471 potential peptides were identified by MALDI-MSI. Our results show that two unidentified m/z values (1589.876 and 1092.727) had significantly higher intensities in tumours compared to stroma. Ten m/z values were identified to have correlation with biological sex. Survival analysis identified three peptides (Histone H4, Haemoglobin subunit alpha, and Inosine-5’-monophosphate dehydrogenase 2) and two unidentified m/z values (1305.840 and 1661.060) that were significantly higher in patients with shorter survival (0-3 years relative to 4-6 years and 7+ years). This is the first study using MALDI-MSI, combined with LC-MS/MS, on a large cohort of CRLM patients to identify the spatial proteome in this malignancy. Further, we identify several protein candidates that may be suitable for drug targeting or for future prognostic biomarker development.

Expanding MELD exceptions for colorectal liver metastasis: data and policy.

While liver transplant for unresectable colorectal cancer liver metastases (CRLM) has been demonstrated to be a promising treatment in selected patients, the typically low MELD score of these patients and lack of exception points may lead to challenges in receiving a deceased donor liver for transplant. Several studies have shown improved outcomes in select patients with CRLM who undergo liver transplant, and several trials are ongoing and will conclude in the next several years. MELD exception points have recently been proposed in qualifying patients with CRLM to help this group obtain more timely quality allografts. Under the current proposal, patients with CRLM would receive a score of the median MELD at transplant (MMaT) for their center minus 20 with a minimum score of 15 in cases where MMaT minus 20 would be less than 15. This would allow them to receive transplants faster without competing unnecessarily with those with greater medical need. Giving MELD exception points to patients with colorectal cancer liver metastases in need of transplant may decrease time on the waitlist and improve outcomes for these patients.