Hyperthermia exposure induces apoptosis and inhibits proliferation in HCT116 cells by upregulating miR-34a and causing transcriptional activation of p53

Photothermal Hyperthermia Suppresses Liver Tumor Growth Via Hippo Signaling Pathway-Dependent Inhibition of Cell Proliferation and Induction of Apoptosis

Hepatocellular carcinoma (HCC) ranks as the third most common malignant tumor globally. Although hyperthermia has shown promise as a non-invasive treatment for tumors, its specific mechanisms and impact on HCC remain underexplored. This study aims to investigate the effects of hyperthermia on HCC proliferation and apoptosis and to elucidate the role of the Hippo signaling pathway in these processes. Huh7 and HepG2 HCC cells were cultured at various temperatures (37 °C, 40 °C, 43 °C, and 46 °C), with 37 °C as the control. Cell proliferation, apoptosis, and cell cycle distribution were assessed via CCK-8 assays and flow cytometry. A subcutaneous xenograft model in nude mice, treated with indocyanine green (ICG) and near-infrared (NIR) irradiation to achieve local hyperthermia, was used to evaluate in vivo tumor growth. RNA-seq and KEGG pathway analyses identified differentially expressed genes, and Western blotting and immunofluorescence were used to confirm the involvement of the Hippo signaling pathway. Hyperthermia at 43 °C significantly inhibited Huh7 and HepG2 cell proliferation and induced apoptosis, accompanied by cell cycle arrest. In vivo, local hyperthermia reduced tumor volume and weight in the ICG + NIR-treated group. RNA-seq and KEGG analyses revealed that the Hippo signaling pathway was activated under hyperthermic conditions, with YAP expression and nuclear translocation markedly downregulated. Further experiments showed that YAP overexpression mitigated hyperthermia-induced effects on cell proliferation and apoptosis, underscoring the role of the Hippo pathway. These findings demonstrate that hyperthermia inhibits HCC growth by regulating the Hippo signaling pathway, reducing cell proliferation, and promoting apoptosis. This study highlights the potential of hyperthermia as an effective therapeutic approach for HCC, with implications for developing targeted hyperthermic therapies.

Preliminary Insights into the Acute Molecular Responses in C2C12 Myotubes to Hyperthermia and Insulin Treatment

This study investigates the differential gene expression in an immortalized cell line of mouse skeletal myoblasts (C2C12)-derived myotube cells subjected to hyperthermia (40°C) with and without insulin treatment to elucidate the impact of thermal stress on skeletal muscle physiology. Hyperthermia, which occurs during intense physical activity or environmental heat exposure, is known to challenge muscle homeostasis and influence metabolic function. mRNA sequencing revealed that hyperthermia robustly altered gene expression-upregulating key genes involved in glycolysis, oxidative phosphorylation, heat shock response, and apoptosis. These changes are suggestive of an elevated metabolic state and enhanced cellular stress; however, these results remain preliminary without complementary protein or metabolic assays. Notably, insulin treatment moderated many of the hyperthermia-induced transcriptional alterations, particularly affecting genes linked to glucose uptake and metabolism. Together, these findings provide hypothesis-generating insights into the interplay between thermal stress and insulin signaling in C2C12 myotubes, and they underscore potential targets for future mechanistic studies.

The potential of the South African plant Tulbaghia Violacea Harv for the treatment of triple negative breast cancer

Triple-negative breast cancer (TNBC) is difficult to treat and has a low five-year survival rate. In South Africa, a large percentage of the population still relies on traditional plant-based medicine. To establish the utility of both methanol and water-soluble extracts from the leaves of Tulbaghia violacea, cytotoxicity assays were carried out to establish the IC50 values against a TNBC cell line. Cell cycle and apoptosis assays were carried out using the extracts. To identify the molecular compounds, present in water-soluble leaf extracts, NMR spectroscopy was performed. Compounds of interest were then used in computational docking studies with the anti-apoptotic protein COX-2. The IC50 values for the water- and methanol-soluble extracts were determined to be 400 and 820 µg/mL, respectively. The water-soluble extract induced apoptosis in the TNBC cell line to a greater extent than in the normal cell line. RNAseq indicated that there was an increase in the transcription of pro-apoptotic genes in the TNBC cell line. The crude extract also caused these cells to stall in the S phase. Of the 61 compounds identified in this extract, five demonstrated a high binding affinity for COX-2. Based on these findings, the compounds within the extract show significant potential for further investigation as candidates for the development of cancer therapeutics, particularly for TNBC.

Targeted intra-tumoral hyperthermia using uniquely biocompatible gold nanorods induces strong immunogenic cell death in two immunogenically 'cold' tumor models

Introduction

Hyperthermia is an established adjunct in multimodal cancer treatments, with mechanisms including cell death, immune modulation, and vascular changes. Traditional hyperthermia applications are resource-intensive and often associated with patient morbidity, limiting their clinical accessibility. Gold nanorods (GNRs) offer a precise, minimally invasive alternative by leveraging near-infrared (NIR) light to deliver targeted hyperthermia therapy (THT). THT induces controlled tumor heating, promoting immunogenic cell death (ICD) and modulating the tumor microenvironment (TME) to enhance immune engagement. This study explores the synergistic potential of GNR-mediated THT with immunotherapies in immunogenically 'cold' tumors to achieve durable anti-tumor immunity.

Methods

GNRs from Sona Nanotech Inc.™ were intratumorally injected and activated using NIR light to induce mild hyperthermia (42-48°C) for 5 minutes. Tumor responses were analyzed for cell death pathways and immune modulation. The immunogenic effects of THT were assessed alone and in combination with intratumoral interleukin-2 (i.t. IL-2) or systemic PD-1 immune checkpoint blockade. Immune cell infiltration, gene expression changes, and tumor growth kinetics were evaluated.

Results

THT reduced tumor burden through cell death mechanisms, including upregulated ICD marked by calreticulin exposure within 48 hours. By 48 hours, CD45+ immune cell levels were increased, including increased levels of immunosuppressive M2 macrophages. While THT led to innate immune cell stimulations highlighted by gene expression upregulation in the STING cGAS pathway and enhanced M1 and dendritic cell levels, tumor regrowth was observed within six days post-treatment. To enhance THT's immunogenic effects, the therapy was combined with intratumoral interleukin-2 (i.t. IL-2) or systemic PD-1 immune checkpoint blockade. Sequential administration of i.t. IL-2 post-THT induced robust CD8+ T-cell infiltration and led to sustained tumor regression in both treated and distant tumors, accompanied by the emergence of memory T cells. However, IL-2-induced immunosuppressive T-reg populations were also sustained to tumor endpoint suggesting that therapy could be further enhanced. Additionally, PD-1 expression, which was upregulated in CD8+ T cells by THT, was targeted with systemic PD-1 inhibition, further augmenting immune engagement within the TME.

Discussion

These combinatory treatments demonstrated synergistic effects, promoting durable anti-tumor responses and immune memory. Collectively, GNR-mediated THT effectively reduces tumor burden and remodels the TME, potentiating systemic immunity and enhancing the impact of complementary immunotherapies.

Cordycepin enhances hyperthermia-induced apoptosis and cell cycle arrest by modulating the MAPK pathway in human lymphoma U937 cells

BACKGROUND

Hyperthermia induces cancer cell death. However, the cytotoxic effect of hyperthermia is not sufficient. Cordycepin can also induce apoptosis in cancer cells and enhance the antitumoral activity of irradiation. To examine cordycepin-mediated enhancement of hyperthermia-induced apoptosis, this study investigated the combined effects and apoptotic mechanisms of hyperthermia and cordycepin on human leukemia U937 cells.

METHODS

Cell viability and apoptosis were measured using MTT assays, Hoechst 33342 staining and Annexin V/PI double staining. The distribution of the cell cycle and sub-G1 phase, reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were examined by flow cytometry. The expression of related proteins was analyzed by western blotting.

RESULTS

Combined treatment with hyperthermia and cordycepin markedly augmented apoptosis by upregulating Bax and suppressing Bcl-2, Bid and activated caspase 3 and 8 expression, and apoptosis was decreased by Z-VAD-fmk (a pan caspase inhibitor). We also found that the MMP was significantly decreased and excessive ROS generation occurred. The combination treatment also induced arrest in the G2/M phase by downregulating cyclin dependent kinase 1 (CDK1) and cyclin B1 protein expression. Furthermore, it was observed that mitogen-activated protein kinase (MAPK) pathway including ERK, JNK and p38 signals was involved in the induction of apoptosis. The phosphorylated p38 and JNK were increased and ERK phosphorylation was decreased by the combined treatment. In addition, N-acetyl-L-cysteine (NAC) significantly protected the cells by restoring ROS levels and the activity of caspase-3, inactivating the MAPK pathway.

CONCLUSION

Cordycepin significantly enhanced hyperthermia-induced apoptosis and G2/M phase arrest in U937 cells. The combined treatment enhanced apoptosis through the MAPK pathway and mitochondrial dysfunction, and these effects could be rescued by NAC. We report for the first time that cordycepin can be used as a hyperthermia sensitizer to treat leukemia.

Crosstalk between Endoplasmic Reticulum Stress and Oxidative Stress in Heat Exposure-Induced Apoptosis Is Dependent on the ATF4-CHOP-CHAC1 Signal Pathway in IPEC-J2 Cells

The intestinal epithelium is susceptible to heat stress (HS), which leads to gut leakage and inflammation. However, the mechanisms underlying HS-induced intestine dysfunction have yet to be elucidated. We established an in vitro chronic heat exposure-induced intestinal injury of intestinal porcine epithelial cells (IPEC-J2) exposed to high temperatures (43 °C) for 12 h. The results revealed that HS increased reactive oxygen species (ROS) generation and decreased superoxide dismutase 2 (SOD2) expression, leading to oxidative stress. Western blotting analysis demonstrated that HS induced apoptosis as evidenced by increased cytochrome c (Cyt c) release in the cytoplasm and caspase 3 activation. Transcriptome sequencing analysis revealed that HS activated the endoplasmic reticulum stress (ERS) response/unfolded protein response (UPR) but inhibited glutathione metabolism. Specifically, HS triggered the pro-apoptotic activating transcription factor 4 (ATF4)/CEBP-homologous protein (CHOP) branch of the UPR. Interestingly, glutathione-specific gamma-glutamylcyclotransferase1 (CHAC1) involved in glutathione degradation was upregulated due to heat exposure and was proved to be downstream of the ATF4-CHOP signal pathway. Knockdown of CHAC1 attenuated the HS-induced decrease in glutathione level and cell apoptosis. These studies suggest that crosstalk between ERS and oxidative stress in HS-induced apoptosis might be dependent on the ATF4-CHOP-CHAC1 signal pathway in IPEC-J2 cells.

Preclinical In Vivo-Models to Investigate HIPEC; Current Methodologies and Challenges

Simple Summary

Efficacy of cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) depends on patient selection, tumor type, delivery technique, and treatment parameters such as temperature, carrier solution, type of drug, dosage, volume, and treatment duration. Preclinical research offers a powerful tool to investigate the impact of these parameters and to assists in designing potentially more effective treatment protocols and clinical trials. This study aims to review the objectives, methods, and clinical relevance of in vivo preclinical HIPEC studies found in the literature. In total, 60 articles were included in this study. The selected articles were screened on the HIPEC parameters. Recommendations are provided and possible pitfalls are discussed on the choice of type of animal and tumor model per stratified parameters and study goal. The guidelines presented in this paper can improve the clinical relevance and impact of future in vivo HIPEC experiments.

Abstract

Hyperthermic intraperitoneal chemotherapy (HIPEC) is a treatment modality for patients with peritoneal metastasis (PM) of various origins which aims for cure in combination with cytoreductive surgery (CRS). Efficacy of CRS-HIPEC depends on patient selection, tumor type, delivery technique, and treatment parameters such as temperature, carrier solution, type of drug, dosage, volume, and treatment duration. Preclinical research offers a powerful tool to investigate the impact of these parameters and to assist in designing potentially more effective treatment protocols and clinical trials. The different methodologies for peritoneal disease and HIPEC are variable. This study aims to review the objectives, methods, and clinical relevance of in vivo preclinical HIPEC studies found in the literature. In this review, recommendations are provided and possible pitfalls are discussed on the choice of type of animal and tumor model per stratified parameters and study goal. The guidelines presented in this paper can improve the clinical relevance and impact of future in vivo HIPEC experiments.

The Temperature-Dependent Effectiveness of Platinum-Based Drugs Mitomycin-C and 5-FU during Hyperthermic Intraperitoneal Chemotherapy (HIPEC) in Colorectal Cancer Cell Lines

Cytoreductive surgery (CRS) followed by hyperthermic intraperitoneal chemotherapy (HIPEC) is a treatment with curative intent for peritoneal metastasis of colorectal cancer (CRC). Currently, there is no standardized HIPEC protocol: choice of drug, perfusate temperature, and duration of treatment vary per institute. We investigated the temperature-dependent effectiveness of drugs often used in HIPEC.

METHODS

The effect of temperature on drug uptake, DNA damage, apoptosis, cell cycle distribution, and cell growth were assessed using the temperature-dependent IC50 and Thermal Enhancement Ratio (TER) values of the chemotherapeutic drugs cisplatin, oxaliplatin, carboplatin, mitomycin-C (MMC), and 5-fluorouracil (5-FU) on 2D and 3D CRC cell cultures at clinically relevant hyperthermic conditions (38-43 °C/60 min).

RESULTS

Hyperthermia alone decreased cell viability and clonogenicity of all cell lines. Treatment with platinum-based drugs and MMC resulted in G2-arrest. Platinum-based drugs display a temperature-dependent synergy with heat, with increased drug uptake, DNA damage, and apoptosis at elevated temperatures. Apoptotic levels increased after treatment with MMC or 5-FU, without a synergy with heat.

CONCLUSION

Our in vitro results demonstrate that a 60-min exposure of platinum-based drugs and MMC are effective in treating 2D and 3D CRC cell cultures, where platinum-based drugs require hyperthermia (>41 °C) to augment effectivity, suggesting that they are, in principle, suitable for HIPEC.

MiR-126 promotes esophageal squamous cell carcinoma via inhibition of apoptosis and autophagy

MiRNA-126 (miR-126) has been shown to be involved in various malignancies as well as other biological processes. However, currently, its role in esophageal squamous cell carcinoma (ESCC) is not well understood. The present study is focused on the mechanisms that underlie the effect of miR-126 on cell survival and death (apoptosis and autophagy) in ESCC cells. MiR-126 expression was found to be enhanced in ESCC cells and tissues. Downregulation of miR-126 suppressed cell survival, and TUNEL staining indicated that miR-126 inhibition promoted ESCC cell death. In addition, the production of LC3B and p62 proteins, two autophagy signals, was reduced following miR-126 inhibition. A dual luciferase reporter assay demonstrated that the STAT3 3’-UTR is a direct target of miR-126. Furthermore, STAT3 knock-down rescued the effects on autophagy and apoptosis caused by miR-126 inhibition in ESCC cells. The results of this study may provide some insight into the molecular and biological mechanisms underlying ESCC generation and contribute to the development of novel therapeutic approaches for ESCC.

MiR-34a affects dexmedetomidine-inhibited chronic inflammatory visceral pain by targeting to HDAC2

Background

Dexmedetomidine (DEX) has been used as an anesthetic for decades. The present investigation aimed to elucidate the analgesic impact of DEX on 2,4,6-Trinitrobenzenesulfonic acid (TNBS)-induced chronic inflammatory visceral pain (CIVP) in rats.

Methods

TNBS with or without DEX to Male Sprague-Dawley SD rats were randomly divided into four groups: normal, CIVP, DEX, and vehicle. Pain behaviors were assessed and the abdominal withdrawal reflex, mechanical withdrawal threshold, and thermal withdrawal latency were recorded. Quantitative polymerase chain reaction data showed increased expressions of pro-inflammatory cytokines (IL-6, IL-1β and TNF-α) in the spinal cord tissues of rats.

Results

RNA microarray and quantitative polymerase chain reaction results indicated that miR-34a was downregulated by TNBS induction, but it was upregulated by DEX administration. Further studies showed that transfection of adenovirus-miR-34a inhibitor reversed the effect of DEX on the pain behaviors and spinal-cord pro-inflammatory-cytokine generation in CIVP rats. Additionally, we found that miR-34a targeted the 3′-UTR of the HDAC2 gene, as evinced by the increased HDAC2 expression in the CIVP and DEX + miR-34a inhibitor groups, and decreased HDAC2 signaling in the DEX group. Moreover, knock-down of HDAC2 restored DEX-attenuated pain behaviors and reduced pro-inflammatory cytokine production.

Conclusions

DEX thus exhibited an analgesic effect on CIVP rats through the miR-34a-mediated HDAC2 pathway and suppressed visceral hypersensitivity.

microRNA-1225 inhibit apoptosis of pancreatic cancer cells via targeting JAK1

The microRNA miRNA-1225-5p (miR-1225) is known as an essential modulator of the development of multiple cancers and other biological reactions. However, the understanding of its contribution to pancreatic cancer (PC) is insufficient. The effects of miR-1225 on PC cell survival and tumorigenesis in vivo as well as on the modulation of cell apoptosis were investigated. The expression of miR-1225 was upregulated in 20 human LC samples from acute myeloid leukemia patients with adverse prognosis and poor responses to therapy as well as in several human PC cell lines, as compared to that in healthy tissues, normal tissues, and normal pancreatic cells. In contrast, Janus kinase 1 (JAK1) expression was downregulated in human-derived PC samples and PC cell lines. EdU staining demonstrated that the aberrant expression of miR-1225 impaired the proliferation and survival of these two PC cell lines. The depletion of miR-1225 expression increased the apoptosis of both PANC-1 and AsPC-1 cells, as revealed by the TdT-mediated dUTP nick end labeling (TUNEL) staining and flow cytometry results. The results of dual-luciferase reporter assay indicated that miR-1225 targeted the 3'-untranslated region of JAK1 for silencing. Silencing of JAK1 expression counteracted the suppressive influence of miR-1225 depletion in PC cells. Thus, these results offer an insight into the biological and molecular mechanisms underlying the development of PC and provide potential strategies for PC treatment.