Liver cancer cells are sensitive to Lanatoside C induced cell death independent of their PTEN status

Abstract

a b s t r a c tBackground: Hepatocellular carcinoma is the second deadliest cancer with limited treatment options. Loss of PTEN causes the P13K/Akt pathway to be hyperactive which contributes to cell survival and resistance to therapeutics in various cancers, including the liver cancer. Hence molecules targeting this pathway present good therapeutic strategies for liver cancer. Hypothesis: It was previously reported that Cardiac glycosides possessed antitumor activity by inducing apoptosis of multiple cancer cells through oxidative stress. However, whether Cardiac glycoside Lanatoside C can induce oxidative stress in liver cancer cells and induce cell death both in vitro and in vivo remains unknown. Methods: Cell viability was measured by SRB assay. Cell death analysis was investigated by propidium iodide staining with flow cytometry and PARP cleavage. DCFH-DA staining and cytometry were used for intracellular ROS measurement. Protein levels were analyzed by western blot analysis. Antitumor activity was investigated on mice xenografts in vivo. Results: In this study, we found that Cardiac glycosides, particularly Lanatoside C from Digitalis ferruginea could significantly inhibit PTEN protein adequate Huh7 and PTEN deficient Mahlavu human liver cancer cell proliferation by the induction of apoptosis and G2/M arrest in the cells. Lanatoside C was further shown to induce oxidative stress and alter ERK and Akt pathways. Consequently, JNK1 activation resulted in extrinsic apoptotic pathway stimulation in both cells while JNK2 activation involved in the inhibition of cell survival only in PTEN deficient cells. Furthermore, nude mice xenografts followed by MRI showed that Lanatoside C caused a significant decrease in the tumor size. In this study apoptosis induction by Lanatoside C was characterized through ROS altered ERK and Akt pathways in both PTEN adequate epithelial and deficient mesenchymal liver cancer cells. Conclusion:The results indicated that Lanatoside C could be contemplated in liver cancer therapeutics, particularly in PTEN deficient tumors. This is due to Lanatoside C's stress inducing action on ERK and Akt pathways through differential activation of JNK1 and JNK2 by GSK3β.

Elimination of undifferentiated human embryonic stem cells by cardiac glycosides

“…Digoxin was found to inhibit several types of cancer cells, such as breast cancer, lymphoma, melanoma, myeloma, and small cell lung cancer 36–38 . Lanatoside C was also demonstrated to inhibit tumor growth, such as colorectal cancer and human hepatocellular carcinoma 39–41 . For synergistic cancer therapy, lanatoside C combined with TRAIL-secreted neural stem cells can target glioblastoma 42 .…”

Synthesis of new derivatives of boehmeriasin A and their biological evaluation in liver cancer

“…The effect of these compounds on cell cycle protein expression is more pronounced on Huh7 cells ( Figure 5B). Mahlavu cells are reported as more resistant to small molecule inhibitors due to PTEN deletion in PI3K/Akt signaling pathway [25]. The effect of the compounds can still be observed even in these cells.…”

Quinoides and VEGFR2 TKIs influence the fate of hepatocellular carcinoma and its cancer stem cells

“…Huh7 and Hep3B cells carry epithelial features, whereas Mahlavu and SNU-475 cells carry migratory mesenchymal-like properties. 6,7 Furthermore, Huh7 and Hep3B cells differ in their p53 gene status: Huh7 cells express p53IJY220S), but Hep3B cells are null for the TP53 gene. There-fore, the expression of mutant p53 causes differential activation of the β-catenin protein and its downstream mesenchymal proteins such as E-cadherin, vimentin, snail and slug.…”

“…It was shown that Mahlavu and SNU-475 cells have constitutively active Akt protein due to loss of the PTEN tumor suppressor. 7 Current studies and clinical trials focus on the anti-CSC compounds targeting extracellular mediators or cell surface molecules as well as molecules involved in EMT and metastasis. 8 Thus, it is crucial to define which marker is efficient to detect and analyse cancer stem cell markers in each cell line, which we studied by flow cytometry.…”