Activated leukocyte cell adhesion molecule regulates the interaction between pancreatic cancer cells and stellate cells

Galectin-8 Immunohistochemical Profile in Pancreatic Ductal Adenocarcinoma: Emerging Evidence for Its Prognostic Role

Pancreatic ductal adenocarcinoma (PDAC) represents the most frequent pancreatic malignancy, with stromal and epithelial heterogeneity reflected in outcome variability. Therefore, a molecular classification is promoted based on the validation of new diagnostic and prognostic markers. Galectin-8 (Gal8) has been pointed out as a prognostic factor for survival in several types of tumors. Due to limited existing data on PDAC, our study aimed to evaluate the Gal8 profile in PDAC alongside its prognostic status. A total of 87 cases of PDAC were immunohistochemically investigated, and Gal8 immunoexpression was qualitatively and semi-quantitatively assessed and correlated with classical clinicopathological parameters and survival. Gal8 immunoexpression was identified to be mostly nuclear and cytoplasmic, followed by exclusively cytoplasmic and exclusively nuclear. A statistical analysis between Gal8 profiles defined by negative, low, or high scores and clinicopathological characteristics showed significant differences in tumor size, pN stage, and lympho-vascular invasion. Although a Cox regression analysis did not support the prognostic status of Gal8, and we did not confirm its relationship with OS, our results show that exclusively nuclear labeling was associated with an increased mean OS compared with cytoplasmic and nuclear labeling (29.37 vs. 17.93 months). To the best of our knowledge, this is the first study to report a detailed pattern of Gal8 immunostaining in PDAC and to correlate this pattern with clinicopathological characteristics and survival. Our results show that Gal8 immunoexpression is associated with a more aggressive phenotype, thus opening perspectives for larger studies to validate Gal8 as a prognostic factor.

Characterization of CD166 from Nile tilapia (Oreochromis niloticus) displays a broad pathogen recognition spectrum and involved the immune response to microbial aggression

CD166 is a member of the immunoglobulin superfamily of cell adhesion molecules, and its mediated adhesion plays a crucial role in different physiological and pathological phenomena, especially related to leukocyte extravasation, immune synapse stability, T cell activation and proliferation. In this study, CD166 was identified from Nile tilapia (Oreochromis niloticus, OnCD166). OnCD166 contains an open reading frame of 1671 bp that encodes a peptide of 556 amino acids, and contains five consecutive extracellular immunoglobulin domains. It's tissue distribution and expression patterns after S. agalactiae challenge were also investigated. OnCD166 is widely distributed in various tissues of healthy tilapia. After Streptococcus agalactiae challenge, OnCD166 expressions were significantly up-regulated in all tested immune tissues. Meanwhile, the recombinant OnCD166 (rOnCD166E) protein showed strong agglutinating activities against both Gram-negative bacteria and Gram-positive bacteria. Moreover, rOnCD166E could promote phagocytosis of macrophages. Taken together, our results illustrated that OnCD166 might as a receptor involved in the immune recognition and phagocytosis against invading pathogen, which play important roles in the immune responses of Nile tilapia against bacterial pathogens.

ALCAM: A Novel Surface Marker on EpCAMlow Circulating Tumor Cells

Background: Current strategies in circulating tumor cell (CTC) isolation in pancreatic cancer heavily rely on the EpCAM and cytokeratin cell status. EpCAM is generally not considered a good marker given its transitory change during Epithelial to Mesenchymal Transition (EMT) or reverse EMT. There is a need to identify other surface markers to capture the complete repertoire of PDAC CTCs. The primary objective of the study is to characterize alternate surface biomarkers to EpCAM on CTCs that express low or negligible levels of surface EpCAM in pancreatic cancer patients. Methods: Flow cytometry and surface mass spectrometry were used to identify proteins expressed on the surface of PDAC CTCs in culture. CTCs were grown under conditions of attachment and in co-culture with naïve neutrophils. Putative biomarkers were then validated in GEMMs and patient samples. Results: Surface proteomic profiling of CTCs identified several novel protein biomarkers. ALCAM was identified as a novel robust marker in GEMM models and in patient samples. Conclusions: We identified several novel surface biomarkers on CTCs expressed under differing conditions of culture. ALCAM was validated and identified as a novel alternate surface marker on EpCAMlow CTCs.

Activated leukocyte cell adhesion molecule (ALCAM)/CD166 in pancreatic cancer, a pivotal link to clinical outcome and vascular embolism

Activated leukocyte cell adhesion molecule (ALCAM, or CD166) is a cell adhesion molecule and one of potential tumour metastasis 'soil' receptors that via homotypic and heterotypic interactions, mediates cancer cell adhesion. The present study investigated clinical, pathological and prognostic values of ALCAM in patients with pancreatic cancer. Human pancreatic cancer (PANC-1 and Mia PaCa-2) and human vascular endothelial cell lines were used to construct cell models differentially expressing levels of ALCAM. Tumour-endothelial interaction and tumour migration were assessed by a DiI-based method and electric cell-substrate impedance sensing (ECIS) assay. Pancreatic cancer tissues (n=223), collected immediately after surgery, were analysed for levels of the ALCAM transcripts, which were also analysed against clinical, pathological and clinical outcomes of the patients. ALCAM protein was assessed by immunohistochemistry on a tissue array. Our study demonstrate that pancreatic cancer tissues had significantly higher levels of ALCAM transcripts than normal tissues (P<0.00001). There were no significant differences with staging, differentiation and tumour locations. Tumours from patients who died of pancreatic cancer had significantly high levels of ALCAM compared with those who lived (P=0.018), and this finding was further supported by ROC analysis (P=0.016). Multivariant analysis showed that ALCAM is an independent prognosis factor for overall survival (HR=5.485), with both nodal status and TNM staging contributing to the model (HR=2.578 and 3.02, respectively). A surprising finding was the relationship between ALCAM expression and microvessel embolism of tumour cells (P=0.021, with vs without tumour embolism). Levels of ALCAM were found to be a determinant factor to adherence of the pancreatic cancer cells to vascular endothelial cells, as demonstrated by pancreatic cancer cell models genetically engineered to express differential levels of ALCAM. The tumour-endothelial interaction mediated by ALCAM was readily blocked by addition of soluble ALCAM. Our data supports the conclusion that ALCAM expression is aberrant in pancreatic cancer and its raised expression is an independent prognostic factor for the survival of the patients and the microvascular embolism by cancer cells. Our results suggest that ALCAM plays a key role in mediating tumour-endothelial cell interactions and enhancing tumour embolism in pancreatic cancer, and targeting ALCAM represents a potential therapeutic strategy for treating human pancreatic cancer.

The Clinical and Theranostic Values of Activated Leukocyte Cell Adhesion Molecule (ALCAM)/CD166 in Human Solid Cancers

Simple Summary

ALCAM (activated leukocyte cell adhesion molecule) is an important regulator in human cancers, particularly solid tumours. Its expression in cancer tissues has prognostic values depending on cancer types and is also linked to distant metastases. A truncated form, soluble form of ALCAM (sALCAM) in circulation has been suggested to be a prognostic indicator and a potential therapeutic tool. This article summarises recent findings and progress in ALCAM and its involvement in cancer, with a primary focus on its clinical connections and therapeutic values.

Abstract

Activated leukocyte cell adhesion molecule (ALCAM), also known as CD166, is a cell adhesion protein that is found in multiple cell types. ALCAM has multiple and diverse roles in various physiological and pathological conditions, including inflammation and cancer. There has been compelling evidence of ALCAM’s prognostic value in solid cancers, indicating that it is a potential therapeutic target. The present article overviews the recent findings and progress in ALCAM and its involvement in cancer, with a primary focus on its clinical connections in cancer and therapeutic values.

Meta-analysis indicating that high ALCAM expression predicts poor prognosis in colorectal cancer

Activated leukocyte cell adhesion molecule (ALCAM) has been linked to the development and progress of colorectal cancer (CRC). In this meta-analysis, we examined whether ALCAM expression is predictive of survival outcomes in CRC patients. We included 7 studies with 2048 patients in our meta-analysis after searching the PubMed, Cochrane Library, EMBASE, OVID and Web of Science databases. High ALCAM expression was associated with poor overall survival among CRC patients (HR = 1.94, 95%CI = 1.05–3.58, P = 0.03). High ALCAM expression was also associated with aggressive clinicopathological features such as tumor stage (T3,T4/T1,T2; HR = 2.66, 95%CI = 2.01–3.51, P < 0.00001), nodal status (Positive/Negative, HR = 2.12, 95%CI = 1.61–2.82, P < 0.00001), distant metastasis (M1/M0, HR = 3.30, 95%CI = 2,21–4.91, P < 0.00001), tumor grade (grade3/grade1,2, HR = 1,28, 95% CI = 1.00–1.62, P = 0.05), and patient age (> 60/< 60, HR = 1.29, 95%CI = 1.01–1.66, P = 0.05). These findings indicate that high ALCAM expression is associated with poor prognosis and advanced clinicopathological characteristics in CRC patients.