panobinostat and Uterine-Cervical-Neoplasms

The study aims to investigate the apoptotic effects of combining LBH589 and AM1241 (a selective CB2 receptor agonist) on cervical cancer cells and elucidating the mechanism of this combined therapy, which may provide innovative strategies for treating this disease.. The viability of the cervical cancer cells was measured by cell counting kit-8 (CCK-8) assay, and the synergistic effect was analyzed using SynergyFinder. Cell proliferation was tested by cell cloning. The apoptosis and reactive oxygen species (ROS) production in cervical cancer cells were analyzed by flow cytometry. Western blot and quantitative real-time PCR (qRT-PCR) were employed to determine changes in protein and gene levels of pathway-related factors.. By the results of cytotoxicity assay, SiHa cells were selected and treated with 0.1 μM LBH589 and 4 μM AM1241 for 24 h for subsequent experiments. The combination of both was synergistic as determined by bliss, ZIP, HSA and LOEWE synergy score. Plate cloning results showed that LBH589 combined with AM1241 inhibited the proliferation of cervical cancer cells compared to individual drug. Additionally, compared with LBH589 alone, the combination of LBH589 and AM1241 induced autophagy by increasing LC3II/LC3I and decreasing P62/GAPDH, leading to a significantly higher rate of apoptosis. Pharmacological inhibition of also inhibited apoptosis. Consistently, we found that the endoplasmic reticulum, DNA damage repair pathway were induced after co-administration. Furthermore, cellular ROS increased after co-administration, and apoptosis was inhibited by the addition of ROS scavenger.. LBH589 combined with AM1241 activated the endoplasmic reticulum emergency pathway, DNA damage repair signaling pathway, oxidative stress and autophagy pathway, ultimately promoting the apoptosis of cervical cancer cells. These findings suggest that the co-administration of LBH589 and AM1241 may be a new treatment plan for the treatment of cervical cancer.

Topics: Apoptosis; Autophagy; Female; Humans; Panobinostat; Reactive Oxygen Species; Uterine Cervical Neoplasms

Various combinations of drugs may be effective in the treatment of different types of cancer. Previously, we have shown that combinations of the histone deacetylase inhibitor panobinostat and the topoisomerase inhibitors topotecan or etoposide act synergistically, but the underlying mode of action has remained unknown. Here, we aimed at uncovering the mechanisms underlying this synergism.. The effects of (combinations of) panobinostat and topotecan or etoposide on cervical cancer-derived HeLa and SiHa cells were assessed using morphological evaluations, scratch wound healing assays, cell cycle analyses, AO/EB staining assays, Annexin V/PI staining assays, reactive oxygen species (ROS) and mitochondrial membrane potential measurements and Western blotting.. We found that combinations of panobinostat and the topoisomerase inhibitors topotecan or etoposide synergistically enhanced the induction of apoptosis in both HeLa and SiHa cells. This enhanced apoptosis induction was found to be mediated through increased ROS production and induction of the mitochondrial apoptotic pathway. We also found that the combination treatment resulted in inhibition of the PI3K/AKT and NF-κB pro-survival pathways and in activation of the ERK pathway, which is associated with intrinsic apoptosis.. From our data we conclude that combinations of panobinostat and the topoisomerase inhibitors topotecan or etoposide provoke strong cell death responses in cervical cancer-derived cells via induction of the intrinsic apoptotic pathway. Since this drug combination may potentially be effective in the treatment of cervical cancer, further preclinical investigations are warranted.

Topics: Antineoplastic Agents; Apoptosis; Cell Cycle; Cell Line, Tumor; Female; HeLa Cells; Humans; Hydroxamic Acids; Indoles; Membrane Potential, Mitochondrial; Panobinostat; Reactive Oxygen Species; Topoisomerase Inhibitors; Topotecan; Uterine Cervical Neoplasms; Wound Healing

Cervical cancer is the fourth major cause of cancer-related deaths in women worldwide and is the most common cancer in developing countries. Therefore, a search for novel treatment modalities is warranted. The present study is designed to investigate the effect of pan histone deacetylase inhibitor, 'panobinostat', on cervical cancer cells alone and in combination with topoisomerase inhibitors. We assessed the effect of panobinostat on two cervical cancer cell lines, HeLa and SiHa, for cell viability, apoptosis, oxidative stress and mitochondrial function using various assays. The results indicate that panobinostat reduces the viability of cervical cancer cells in a dose- and time-dependent manner; it arrests HeLa cells in G0/G1 and SiHa cells in G2/M phase of the cell cycle. Panobinostat induced apoptosis through an increase in the ROS production and the disruption of mitochondrial membrane potential. Concomitantly the expression of anti-apoptotic gene Bcl-xL was reduced, while levels of CDK inhibitor p21 and caspase-9 were increased. Panobinostat increased the acetylation of histone H3 indicating HDAC inhibition. In addition, panobinostat also showed synergistic effect with topoisomerase inhibitors mediated by increased activation of caspase-3/7 activity compared to that in cells treated with panobinostat alone. These results suggest a combination therapy using inhibitors of histone deacetylase and topoisomerase together could hold the promise for an effective targeted therapeutic strategy.

Topics: Antineoplastic Agents; Apoptosis; Cell Survival; Dose-Response Relationship, Drug; Drug Synergism; Female; HeLa Cells; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Indoles; Panobinostat; Reactive Oxygen Species; Topoisomerase Inhibitors; Uterine Cervical Neoplasms