α-Hederin Increases The Apoptosis Of Cisplatin-Resistant Gastric Cancer Cells By Activating Mitochondrial Pathway In Vivo And Vitro

Molecular mechanism of α-Hederin in tumor progression

α-Hederin is a monosaccharide pentacyclic triterpene saponin compound derived from the Chinese herb, Pulsatilla. It has garnered considerable attention for its anti-tumor, anti-inflammatory, and spasmolytic pharmacological activities. Given the rising incidence of cancer and the pronounced adverse reactions associated with chemotherapy drugs-which profoundly impact the quality of life for cancer patients-there is an immediate need for safe and effective antitumor agents. Traditional drugs and their anticancer effects have become a focal point of research in recent years. Studies indicate that α-Hederin can hinder tumor cell proliferation and impede the advancement of various cancers, including breast, lung, colorectal, and liver cancers. The principal mechanism behind its anti-tumor activity involves inhibiting tumor cell proliferation, facilitating tumor cell apoptosis, and arresting the cell cycle process. Current evidence suggests that α-Hederin can exert its anti-tumor properties through diverse mechanisms, positioning it as a promising agent in anti-tumor therapy. However, a comprehensive literature search revealed a gap in the comprehensive understanding of α-Hederin. This paper aims to review the available literature on the anti-tumor mechanisms of α-Hederin, hoping to provide valuable insights for the clinical treatment of malignant tumors and the innovation of novel anti-tumor medications.

Anticancer properties and mechanism insights of α-hederin

α-Hederin is a natural bioactive molecule very abundant in aromatic and medicinal plants (AMP). It was identified, characterized, and isolated using different extraction and characterization technologies, such as HPLC, LC-MS and NMR. Biological tests have revealed that this natural molecule possesses different biological properties, particularly anticancer activity. Indeed, this activity has been investigated against several cancers (e.g., esophageal, hepatic, breast, colon, colorectal, lung, ovarian, and gastric). The underlying mechanisms are varied and include induction of apoptosis and cell cycle arrest, reduction of ATP generation, as well as inhibition of autophagy, cell proliferation, invasion, and metastasis. In fact, these anticancer mechanisms are considered the most targeted for new chemotherapeutic agents' development. In the light of all these data, α-hederin could be a very interesting candidate as an anticancer drug for chemotherapy, as well as it could be used in combination with other molecules already validated or possibly investigated as an agent sensitizing tumor cells to chemotherapeutic treatments.

α‑hederin overcomes hypoxia‑mediated drug resistance in colorectal cancer by inhibiting the AKT/Bcl2 pathway

Currently, chemoresistance is a major challenge that directly affects the prognosis of patients with colorectal cancer (CRC). In addition, hypoxia is associated with poor prognosis and therapeutic resistance in patients with cancer. Accumulating evidence has shown that α‑hederin has significant antitumour effects and that α‑hederin can inhibit hypoxia‑mediated drug resistance in CRC; however, the underlying mechanism remains unclear. In the present study, viability and proliferation assays were used to evaluate the effect of α‑hederin on the drug resistance of CRC cells under hypoxia. Sequencing analysis and apoptosis assays were used to determine the effect of α‑hederin on apoptosis under hypoxia. Western blot analysis and reverse transcription‑quantitative PCR were used to measure apoptosis‑related protein and mRNA expression levels. Furthermore, different mouse models were established to study the effect of α‑hederin on hypoxia‑mediated CRC drug resistance in vivo. In the present study, the high expression of Bcl2 in hypoxic CRC cells was revealed to be a key factor in their drug resistance, whereas α‑hederin inhibited the expression of Bcl2 by reducing AKT phosphorylation in vitro and in vivo, and promoted the apoptosis of CRC cells under hypoxia. By contrast, overexpression of AKT reversed the effect of α‑hederin on CRC cell apoptosis under hypoxia. Taken together, these results suggested that α‑hederin may overcome hypoxia‑mediated drug resistance in CRC by inhibiting the AKT/Bcl2 pathway. In the future, α‑hederin may be used as a novel adjuvant for reversing drug resistance in CRC.

Effects and Mechanisms of Saikosaponin D Improving the Sensitivity of Human Gastric Cancer Cells to Cisplatin

Gastric cancer (GC) is the second leading cause of cancer deaths around the world. Chemoresistance is an important reason for poor prognosis of GC. Saikosaponin D (SSD) is a natural constituent from Radix Bupleuri and exhibits various activities including antitumors. This study investigated the effects and the mechanisms of SSD on cisplatin (cis-diamminedichloroplatinum, DDP) sensitivity of GC cells. Findings suggested that SSD could promote the inhibitory effect of DDP on proliferation and invasion and increase DDP-induced apoptosis in SGC-7901 and DDP-resistant cell line SGC-7901/DDP. We further identified that SSD increased levels of LC3 B and cleaved caspase 3 and decreased levels of p62, IKK β, p-IκB α, and NF-κB p65, suggesting that SSD might inhibit the IKK β/NF-κB pathway and induce both cell autophagy and apoptosis in SGC-7901 and SGC-7901/DDP. A further study indicated that SSD enhanced the effect of DDP-induced cleaved caspase 3 level rise and NF-κB pathway suppression, especially in SGC-7901/DDP cells. Conclusively, SSD enhanced DDP sensitivity of GC cells; the potential molecular mechanisms were that SSD-induced apoptosis and autophagy and inhibited the IKK β/NF-κB pathway in GC cells. These findings suggested that SSD might contribute to overcoming DDP resistance in GC treatment.

Elucidating Role of Reactive Oxygen Species (ROS) in Cisplatin Chemotherapy: A Focus on Molecular Pathways and Possible Therapeutic Strategies

The failure of chemotherapy is a major challenge nowadays, and in order to ensure effective treatment of cancer patients, it is of great importance to reveal the molecular pathways and mechanisms involved in chemoresistance. Cisplatin (CP) is a platinum-containing drug with anti-tumor activity against different cancers in both pre-clinical and clinical studies. However, drug resistance has restricted its potential in the treatment of cancer patients. CP can promote levels of free radicals, particularly reactive oxygen species (ROS) to induce cell death. Due to the double-edged sword role of ROS in cancer as a pro-survival or pro-death mechanism, ROS can result in CP resistance. In the present review, association of ROS with CP sensitivity/resistance is discussed, and in particular, how molecular pathways, both upstream and downstream targets, can affect the response of cancer cells to CP chemotherapy. Furthermore, anti-tumor compounds, such as curcumin, emodin, chloroquine that regulate ROS and related molecular pathways in increasing CP sensitivity are described. Nanoparticles can provide co-delivery of CP with anti-tumor agents and by mediating photodynamic therapy, and induce ROS overgeneration to trigger CP sensitivity. Genetic tools, such as small interfering RNA (siRNA) can down-regulate molecular pathways such as HIF-1α and Nrf2 to promote ROS levels, leading to CP sensitivity. Considering the relationship between ROS and CP chemotherapy, and translating these findings to clinic can pave the way for effective treatment of cancer patients.

LncRNA-SNHG7 interferes with miR-34a to de-sensitize gastric cancer cells to cisplatin

Gastric cancer (GC) remains poor prognosis and survival issues due to the resistance of chemotherapies, such as cisplatin. The long non-coding RNA small nucleolar RNA host gene 7 (lncRNA-SNHG7) is known as an oncogenic molecule in diverse cancers. Here, we demonstrate that SNHG7 was significantly upregulated in gastric cancer and positively correlated with cisplatin resistance of gastric cancer cells that SNHG7 was significantly upregulated in cisplatin resistant cells. Silencing SNHG7 dramatically sensitized cisplatin resistant cells. In contrast, a negative correlation between lncRNA-SNHG7 and miR-34a was found that miR-34a was downregulated in gastric cancer patient tissues and significantly sensitized cisplatin resistant gastric cancer cells. Intriguingly, bioinformatical analysis indicated miR-34a has putative biding site for SNHG7 and such negative association between SNHG7 and miR-34a was verified in gastric cancer tissues. The cisplatin resistant cells displayed increased glycolysis rate and SNHG7 promoted cellular glycolysis rate of gastric cancer cells. Luciferase assay illustrated LDHA, a glycolysis enzyme, was the direct target of miR-34a. Importantly, inhibiting SNHG7 successfully suppressed LDHA expressions and sensitized cisplatin resistant cells and such inhibitory effects could be recovered by further anti-miR-34a. These findings suggest an important regulator mechanism for the SNHG7-mediated cisplatin resistance via miR-34a/LDHA-glycolysis axis.

Piezo type mechanosensitive ion channel component 1 facilitates gastric cancer omentum metastasis

The peritoneum, especially the omentum, is a common site for gastric cancer (GC) metastasis. Our aim was to expound the role and mechanisms of Piezo1 on GC omentum metastasis. A series of functional assays were performed to examine cell proliferation, clone formation, apoptosis, Ca²⁺ influx, mitochondrial membrane potential (MMP) and migration after overexpression or knockdown of Piezo1. A GC peritoneal implantation and metastasis model was conducted. After infection by si‐Piezo1, the number and growth of tumours were observed in abdominal cavity. Fibre and angiogenesis were tested in metastatic tumour tissues. Piezo1 had higher expression in GC tissues with omentum metastasis and metastatic lymph node tissues than in GC tissues among 110 patients. High Piezo1 expression was associated with lymph metastasis, TNM and distant metastasis. Overexpressed Piezo1 facilitated cell proliferation and suppressed cell apoptosis in GC cells. Moreover, Ca²⁺ influx was elevated after up‐regulation of Piezo1. Piezo1 promoted cell migration and Calpain1/2 expression via up‐regulation of HIF‐1α in GC cells. In vivo, Piezo1 knockdown significantly inhibited peritoneal metastasis of GC cells and blocked EMT process and angiogenesis. Our findings suggested that Piezo1 is a key component during GC omentum metastasis, which could be related to up‐regulation of HIF‐1α.

Chemopreventive effect of α-hederin/carboplatin combination against experimental colon hyperplasia and impact on JNK signaling

Colon cancer is the commonest cancer worldwide. α-Hederin is a monodesmosidic triterpenoid saponin possessing diverse pharmacological activities. The running experiment was designed to test the chemopreventive activity of α-hederin when used as an adjuvant to carboplatin in an experimental model of mouse colon hyperplasia induced by 1,2-dimethylhydrazine (DMH). Fifty male Swiss albino mice were classified into five groups: group (I): saline group, group (II): DMH-induced colon hyperplasia control group, group (III): DMH + carboplatin (5 mg/kg) group, group (IV): DMH + α-hederin (80 mg/kg) group, and group (V): DMH + carboplatin (5 mg/kg)+α-hederin (80 mg/kg) group. Analyzing of colonic tissue indicated that the disease control group showed higher colon levels of phospho-PI3K to total-PI3K, phospho-AKT to total-AKT and cyclin D1 concurrent with lower phospho-JNK/total JNK ratio and caspase 3. However, treatment with α-hederin, in combination with carboplatin, favorably ameliorated phosphorylation of PI3K/AKT/JNK proteins, increased colon caspase 3 and downregulated cyclin D1. Microscopically, α-hederin, in combination with carboplatin, produced the most reduction in the histologic hyperplasia score, enhanced the goblet cell survival in periodic acid Schiff staining and reduced proliferation (Ki-67 immunostaining) in the current colon hyperplasia model. Collectively, the current study highlighted for the first time that using α-hederin as an adjuvant to carboplatin enhanced its chemopreventive activity, improved JNK signaling and increased apoptosis. Hence, further studies are warranted to test α-hederin as a promising candidate with chemotherapeutic agents in treating colon cancer.