<p>Colorectal cancer (CRC) recurrence and therapeutic resistance are largely attributed to cancer stem cells (CSCs), a subpopulation of tumor cells characterized by self-renewal and differentiation capacities. These cells exhibit enhanced antioxidant defenses that maintain redox homeostasis and contribute to resistance against conventional therapies. Cold atmospheric plasma (CAP), a partially ionized gas that generates reactive oxygen and nitrogen species (RONS), has emerged as a promising strategy to exploit redox vulnerabilities in cancer cells; however, its effects on colorectal CSCs remain poorly defined. In this study, CSC-enriched spheroids derived from HT-29 cells were exposed to a helium-based plasma jet for 30 to 240&#xa0;s. CAP-induced hydrogen peroxide (H₂O₂) generation was quantified, cell viability was assessed using the MTT assay, self-renewal capacity was evaluated via sphere-forming efficiency, and the expression of stemness-associated genes (<i>SOX2</i>, <i>OCT4</i>, and <i>NANOG</i>) was analyzed by qPCR. CAP treatment generated H₂O₂ in a time-dependent manner across all tested media, with DMEM/F12 supplemented with 10% FBS exhibiting the highest accumulation. Spheroid viability declined proportionally with increasing exposure duration. Notably, CAP markedly suppressed self-renewal capacity. Control spheroids reached a diameter of 247&#xa0;μm, whereas 240-second CAP exposure reduced the diameter to 87&#xa0;μm (p &lt; 0.0001), corresponding to a 65% reduction. At the molecular level, <i>OCT4</i> expression increased by twofold (<i>p</i> &lt; 0.01), while <i>SOX2</i> and <i>NANOG</i> expression levels remained unchanged. Overall, CAP limits regrowth of HT-29 CSC-enriched spheroids in a time-dependent manner, consistent with ROS-associated oxidative stress, as reflected by H₂O₂ accumulation. The stemness transcriptional response was not uniform with increased <i>OCT4</i> expression, but unchanged <i>SOX2</i> and <i>NANOG</i> levels. These findings warrant further translational investigation, including comprehensive reactive-species profiling. </p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Effects of helium cold atmospheric plasma (CAP) on HT-29 cancer stem cell spheroid

  • Glavizh Adibhesami,
  • Faezeh Vakhshiteh,
  • Roya Ghods,
  • Elmira Gheytanchi,
  • Seyedeh Masoumeh Amiri Lachgorabi,
  • Mahdiyeh Bakhtiyari-Ramezani,
  • Zahra Madjd

摘要

Colorectal cancer (CRC) recurrence and therapeutic resistance are largely attributed to cancer stem cells (CSCs), a subpopulation of tumor cells characterized by self-renewal and differentiation capacities. These cells exhibit enhanced antioxidant defenses that maintain redox homeostasis and contribute to resistance against conventional therapies. Cold atmospheric plasma (CAP), a partially ionized gas that generates reactive oxygen and nitrogen species (RONS), has emerged as a promising strategy to exploit redox vulnerabilities in cancer cells; however, its effects on colorectal CSCs remain poorly defined. In this study, CSC-enriched spheroids derived from HT-29 cells were exposed to a helium-based plasma jet for 30 to 240 s. CAP-induced hydrogen peroxide (H₂O₂) generation was quantified, cell viability was assessed using the MTT assay, self-renewal capacity was evaluated via sphere-forming efficiency, and the expression of stemness-associated genes (SOX2, OCT4, and NANOG) was analyzed by qPCR. CAP treatment generated H₂O₂ in a time-dependent manner across all tested media, with DMEM/F12 supplemented with 10% FBS exhibiting the highest accumulation. Spheroid viability declined proportionally with increasing exposure duration. Notably, CAP markedly suppressed self-renewal capacity. Control spheroids reached a diameter of 247 μm, whereas 240-second CAP exposure reduced the diameter to 87 μm (p < 0.0001), corresponding to a 65% reduction. At the molecular level, OCT4 expression increased by twofold (p < 0.01), while SOX2 and NANOG expression levels remained unchanged. Overall, CAP limits regrowth of HT-29 CSC-enriched spheroids in a time-dependent manner, consistent with ROS-associated oxidative stress, as reflected by H₂O₂ accumulation. The stemness transcriptional response was not uniform with increased OCT4 expression, but unchanged SOX2 and NANOG levels. These findings warrant further translational investigation, including comprehensive reactive-species profiling.