The Crosstalk between HepG2 and HMC-III Cells: In Vitro Modulation of Gene Expression with Conditioned Media

Abstract

Epidemiological studies have postulated an inverse correlation between developing cancer and neurodegeneration. It is known that the secretome plays a vital role in cell–cell communication in health and disease; the microglia is the resident macrophage of the central nervous system which maintains neuronal integrity by adapting as the microenvironment changes. The present study aimed to identify, in a cell model, biomarkers that link neurodegenerative diseases to cancer or vice versa. Real-time PCR and western blot analysis were used to characterize the effects on gene and protein expression of human hepatoblastoma (HepG2) and human microglia (HMC-III) cells after exchanging part of their conditioned medium. Biomarkers of the endoplasmic reticulum, and mitophagy and inflammatory processes were evaluated. In both cell types, we observed the activation of cytoprotective mechanisms against any potential pro-oxidant or pro-inflammatory signals present in secretomes. In contrast, HepG2 but not HMC-III cells seem to trigger autophagic processes following treatment with conditioned medium of microglia, thus suggesting a cell-specific adaptive response.

Interplay between Cultured Human Osteoblastic and Skeletal Muscle Cells: Effects of Conditioned Media on Glucose and Fatty Acid Metabolism

“…In this study, we chose to compare metabolic responses of conditioned media-treated cells with non-conditioned cells. This approach has previously been used to explore changes in, e.g., lipolysis and gene expression induced by conditioned medium given to the acceptor cells [30,31]. Another approach would be to use transwell co-cultures [32], allowing indirect cell-to-cell contact; however, due to different culturing conditions for growth and differentiation of myotubes and osteoblastic cells, this approach was difficult to implement.…”

Tumor‐associated macrophages: The key player in hepatoblastoma microenvironment and the promising therapeutic target

“…19 Likewise, an Italian research group found that the culture media of central nervous system resident macrophages (HMC-III cells) induce an autophagic process triggering, as well as cytoprotective effects on the HB cell line (Hep G2) against various pro-inflammatory and pro-oxidant factors. 20 Recently, bioinformatics-based HB studies shed more light on the involvement of TAMs in immune cell invasion. A single-cell RNA-seq analysis of genetic data from 13 treatment-naïve HB patients showed aberrant accumulation of erythroblastic islands (EIs), which restrain anti-tumor immunity and inversely correlate with survival.…”

“…The aforementioned Italian research group also found that the culture media of Hep G2 cells induces the same cytoprotective effects on HMC-III cells. 20 Likewise, The HB cell secretome includes: HGFLP, 15 M-CSF, GM-CSF, 6 and IL-34, 13 known to chemoattract and stimulate TAMs. The secretome also includes: macrophage migration inhibitory factor (MIF), 23 OSM, 17 nitric oxide synthetase 2 (NOS2), 24 and IL-34, 13 found to induce protumor M2 macrophage polarization state.…”

“…15 In the same context, the culture media of both HB cells and TAMs exert cytoprotective effects on each other reciprocally, as mentioned. 20 Such vicious circuits consequently make the tumor more virulent and resistant to the routine therapeutics.…”

“…PSTI is not a mere trypsin inhibitor but also a serine protease inhibitor, known to be a poor prognostic factor in cancer, being involved in aggressive proliferation, vascular invasion, recurrence, and tumor metastasis 19 . Likewise, an Italian research group found that the culture media of central nervous system resident macrophages (HMC‐III cells) induce an autophagic process triggering, as well as cytoprotective effects on the HB cell line (Hep G2) against various pro‐inflammatory and pro‐oxidant factors 20 . Recently, bioinformatics‐based HB studies shed more light on the involvement of TAMs in immune cell invasion.…”