Mechanism of hydrogen on cervical cancer suppression revealed by high‑throughput RNA sequencing

Abstract

Cervical cancer is considered one of the diseases with the highest mortality among women and with limited treatment options. Hydrogen (H 2 ) inhalation has been reported to have a variety of tumor-suppressive effects, but the exact mechanism remains unclear. In the present study, HeLa cervical cancer cells and HaCaT keratinocytes treated with H 2 , and a HeLa xenograft mouse model subjected to H 2 inhalation were established. TUNEL, Cell Counting Kit-8 and Ki67 staining assays were used to detect cell apoptosis and proliferation. Oxidative stress was determined according to the levels of reactive oxygen species, malondialdehyde and superoxide dismutase. Tumor growth was recorded every 3 days, and the excised tumors were stained with hematoxylin and eosin. High-throughput RNA sequencing and subsequent Gene Ontology (GO) enrichment analysis were performed in HeLa-treated and un-treated HeLa cells. The expression of hypoxia-inducible factor (HIF)-1α and NF-κB p65 was verified by western blotting, immunohistochemistry and reverse transcription-quantitative PCR. The results revealed an increased apoptosis rate, and reduced cell proliferation and oxidative stress in H 2 -treated HeLa cells but not in HaCaT cells. Similarly, decreased tumor growth and cell proliferation, and enhanced cell apoptosis were observed in H 2 -treated HeLa tumors. RNA sequencing and GO analysis suggest that downregulated HIF1A (HIF-1α mRNA) and RelA (NF-κB p65) levels, and reduced NF-κB signaling were associated with the antitumor effect of H 2 . Finally, decreased HIF-1α and NF-κB p65 expression both at the transcriptional and translational levels were observed in H 2 -treated HeLa cells and in HeLa-derived tumors. In conclusion, the present study reveals a novel mechanism of H 2 against cervical cancer, which may serve as a potential therapeutic target in clinical practice.

A Systematic Review of Molecular Hydrogen Therapy in Cancer Management

“…In addition, Shang et al, (2018) displayed the therapeutic potential of hydrogen in ovarian cancer. The in vivo studies showed a similar result to Chu et al, (2021)'s study in which tumour growth was suppressed after 6 weeks of hydrogen inhalation. This can be explained through their in vitro studies in which hydrogen can inhibit cancer cell proliferation, invasion, and colony formation.…”

“…A study on cervical cancer demonstrates how H2 had a much lower ROS level compared to the control group (p < 0.01). This suggests the treatment's role in reducing the oxidative stress level even in animal studies (Chu et al, 2021). A common effect also seen in animal models is the suppression of tumour growth through various antitumor mechanisms.…”

“…Although no clinical trials have been included, there are enough studies that do showcase hydrogen's effect on reproductive cancer types. It was found that hydrogen has the ability to shrink tumour growth through minimal cell proliferation which in turns promote cell apoptosis in in vitro studies using HeLa cells (Chu et al, 2021). Yang et al, (2020) did an RNA sequencing analysis to reveal hydrogen can inducing apoptosis through TNF and NF-ϰB pathways in endometrial cancer cells.…”

The Therapeutic Potential of Oxyhydrogen Gas in Oncology: A Study on Epstein–Barr Virus-Immortalised B-Lymphoblastoid (TK6) Cells

“…To assess whether oxyhydrogen would affect the cell viability and proliferation of immortalised immune cells (TK6-B-lymphocytes), this novel enquiry focused on the effects of infusing oxyhydrogen gas into cell culture media in an attempt to simulate the most likely dispersal and retention patterns of the aforementioned gas in the blood or serous fluids. Although it is recognised that an increase in pH may have influenced some aspects of cellular activity, the results of further analysis are congruent with early [56,57] and contemporary research [44][45][46]. Interestingly, Figure 6 evinces a distinct increase in cells in the Sub G1 phase at 24 (Control: 9% vs. 46%) and 48 h (Control: 18% vs. 40%) after oxyhydrogen treatment, concomitant with marked decreases in growth phases 1 (24 h: Control: 39% vs. 25%; 48 h: Control: 37% vs. 31%) and 2 (24 h: Control: 28% vs. 10%; 48 h: Control: 19% vs. 10%).…”

“…To date, the pro-apoptotic, anti-tumor effects of hydrogen therapies on solid tissue cancers have been relatively well-studied [7,8,23,29,[40][41][42][43][44][45][46]. However, investigations into leukaemic and lymphoma cell lines remain largely unexplored.…”