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Kapelanski-Lamoureux, A.

Publications and source records attributed to Kapelanski-Lamoureux, A..

3 recordsLinked to original sources

Disruption of integrin alpha-5/beta-1-dependent transforming growth factor beta-1signaling pathway attenuates vessel co-option in colorectal cancer liver metastases

Colorectal cancer liver metastases (CRCLM) have two major histopathological growth patterns (HGPs) including angiogenic desmoplastic HGP (DHGP) and non-angiogenic replacement HGP (RHGP). The RHGP lesions obtain their blood supply through vessel co-option, where the cancer cells hijack the pre-existing blood vessels of the surrounding liver tissue. Consequently, anti-angiogenic therapies are less efficacious in CRCLM patients with RHGP lesions. Recently, we identified a positive correlation between the expression of Angiopoietin1 (Ang1) and the development of vessel co-opted CRCLM lesions in vivo. However, the mechanisms underlying Ang1 upregulation in vessel co-opting CRCLM lesions are unclear. Herein, we demonstrated that transforming growth factor {beta}1 (TGF{beta}1) modulates the expression of Ang1 in hepatocytes in vitro. Significantly, pharmaceutical inhibition of integrin alpha-5/beta-1 (ITG5{beta}1) through ATN-161 impaired TGF{beta}1-dependent Ang1 expression in vitro and in vivo. Moreover, blocking ITG5{beta}1 attenuated the formation of vessel co-opting lesions. Furthermore, treatment with ATN-161 significantly improved survival in tumour-bearing mice. Taken together, our results suggest the molecular mechanism of Ang1 upregulation in vessel co-opting CRCLM and targeting this pathway may serve as promising therapeutic strategy to overcome the development of vessel co-option in CRCLM.

cancer biology↗

Cancer cells induce hepatocytes apoptosis in co-opted colorectal cancer liver metastatic lesions

Vessel co-option in colorectal cancer liver metastases (CRCLM) has been recognized as one of the mechanistic pathways that contribute to resistance against anti-angiogenic therapy. In vessel co-opted CRCLM lesions, the cancer cells are highly motile that move toward and along the pre-existing sinusoidal vessels and hijack them to gain access to nutrient. The movement of cancer cells is accompanied by replacement of the hepatocytes. However, the molecular mechanisms by which this replacement occurs are unclear yet. To examine the involvement of apoptosis in hepatocytes replacement by cancer cells in co-opted lesions, we conducted immunohistochemical staining for chemonaive CRCLM specimens using pro-apoptotic markers antibody, such as cleaved caspase-3 and cleaved poly (ADP-ribose) polymerase-1 (PARP-1). The results suggested overexpression of pro-apoptotic markers in liver parenchyma of co-opted lesions compared to angiogenic lesions, specifically the hepatocytes that are in close proximity to the cancer cells. Importantly, co-culturing hepatocytes with colorectal cancer cells induced overexpression of pro-apoptotic markers in the hepatocytes. Altogether, these results propose that cancer cells could exploit apoptosis to replace the hepatocytes and establish vessel co-option in CRCLM.

cancer biology↗

Ectopic FVIII expression and misfolding in hepatocytes as a potential cause of human hepatocellular carcinoma

Hemophilia A gene therapy targets hepatocytes to express B domain deleted-(BDD) clotting factor VIII (FVIII) to permit viral encapsidation. Since BDD is prone to misfolding in the endoplasmic reticulum (ER) and ER protein misfolding in hepatocytes followed by high fat diet (HFD) can cause hepatocellular carcinoma (HCC), we studied how FVIII misfolding impacts HCC development using hepatocyte DNA delivery to express three proteins from the same parental vector: 1) well-folded cytosolic dihydrofolate reductase (DHFR); 2) BDD-FVIII, which is prone to misfolding in the ER; and 3) N6-FVIII which folds more efficiently than BDD-FVIII. One week after DNA delivery, when FVIII expression was undetectable, mice were fed HFD for 65 weeks. Remarkably, all mice that received BDD-FVIII vector developed liver tumors, whereas only 58% of mice that received N6 and no mice that received DHFR vector developed liver tumors, suggesting that the degree of protein misfolding in the ER increases predisposition to HCC in the context of a HFD and in the absence of viral transduction. Our findings raise concerns of ectopic BDD-FVIII expression in hepatocytes in the clinic, which poses risks independent of viral vector integration. Limited expression per hepatocyte and/or use of proteins that avoid misfolding may enhance safety. Graphical abstract O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY

cancer biology↗