The inhibitory effect and mechanism of Yi-qi-hua-yu-jie-du decoction on the drug resistance of gastric cancer stem cells based on ABC transporters

Cinobufacini enhances the therapeutic response of 5-Fluorouracil against gastric cancer by targeting cancer stem cells via AKT/GSK-3β/β-catenin signaling axis

BACKGROUND

Gastric cancer stem cells (GCSCs) play crucial role in the development, recurrence, and resistance of gastric cancer (GC). Cinobufacini, a traditional Chinese medicine, offers significant advantages in improving tumor therapy. However, pre-clinical investigation into the antitumor effect and mechanism of Cinobufacini on GC is still lacking. Additionally, it has not been reported whether Cinobufacini is related to cancer stem cells (CSCs).

METHODS

The CCK-8, clone formation, EdU staining, transwell and wound healing experiments were performed to assess the cell toxicity of Cinobufacini and demonstrate the preventive effects of Cinobufacini on proliferation, invasion, and migration of GC cells. Elucidating the underlying mechanism of Cinobufacini in GC based on the transcriptome sequencing. Flow cytometry assays, sphere formation assays, subcutaneous xenograft model in nude mice, and immunofluorescent staining have been used to investigate whether the anti-GC effect of Cinobufacini is associated with GCSCs and enhancing therapeutic response to 5-Fluorouracil (5-FU).

RESULTS

Cinobufacini exerts minimal impact on normal human gastric epithelium cell GES-1, while significantly suppressing the proliferation, invasion, and migration of GC cell lines. Additionally, Cinobufacini attenuates the stemness of GCSCs by disrupting the AKT/GSK-3β/β-catenin signaling cascade. Moreover, Cinobufacin enhances the anti-tumor effects of 5-FU against GCSCs by reducing in vitro sphere formation and inhibiting subcutaneous graft tumor growth in vivo.

CONCLUSIONS

Cinobufacini enhances the therapeutic response of 5-FU against GC by targeting CSCs via AKT/GSK-3β/β-catenin signaling axis. Our findings offer a crucial insight into the molecular mechanism of Cinobufacini's anticancer activity in GC.

1,7-diphenyl-4-hepten-3-one mitigates Alzheimer's-like pathology by inhibiting pyroptosis via activating the Nrf2 pathway

Pyroptosis-mediated neuron death plays a crucial role in neurodegenerative diseases, such as Alzheimer's disease (AD). However, the effect of 1,7-diphenyl-4-hepten-3-one (C1), a natural diarylheptanoid, on AD is unclear. Herein, we investigated the therapeutic effect of C1 on APP/PS1 mice and β-amyloid (Aβ)-induced HT22 cells. Our findings showed that C1 attenuated cognitive impairment and mitigated pathological damage in APP/PS1 mice. Furthermore, we found that C1 prevented oxidative stress damage and decreased the levels of pyroptosis-related proteins. In vitro experiments showed that C1 can improve the proliferation of Aβ-induced HT22 cells and decrease the levels of pyroptosis-related proteins in them. When Nrf2 was silenced, the positive effects of C1 in inhibiting pyroptosis were inhibited. Particularly, the production of pyroptosis-associated proteins, including NLRP3, GSDMD, and caspase-1, and the secretion of pro-inflammatory molecules, including IL-1 and IL-18, were increased. Altogether, these findings indicate that C1 can mitigate AD-like pathology via the inhibition of pyroptosis by activating the Nrf2 pathway. We believe that this study can provide alternative strategies for the prevention and treatment of AD.

Deciphering drug resistance in gastric cancer: Potential mechanisms and future perspectives

Gastric cancer (GC) is a malignant tumor that originates from the epithelium of the gastric mucosa. The latest global cancer statistics show that GC ranks fifth in incidence and fourth in mortality among all cancers, posing a serious threat to public health. While early-stage GC is primarily treated through surgery, chemotherapy is the frontline option for advanced cases. Currently, commonly used chemotherapy regimens include FOLFOX (oxaliplatin + leucovorin + 5-fluorouracil) and XELOX (oxaliplatin + capecitabine). However, with the widespread use of chemotherapy, an increasing number of cases of drug resistance have emerged. This article primarily explores the potential mechanisms of chemotherapy resistance in GC patients from five perspectives: cell death, tumor microenvironment, non-coding RNA, epigenetics, and epithelial-mesenchymal transition. Additionally, it proposes feasibility strategies to overcome drug resistance from four angles: cancer stem cells, tumor microenvironment, natural products, and combined therapy. The hope is that this article will provide guidance for researchers in the field and bring hope to more GC patients.

Inhibition of PI3K/Akt/mTOR Signaling Pathway Suppresses 5-Fluorouracil Resistance in Gastric Cancer

BACKGROUND

At present, 5-Fluorouracil (5-FU) is a crucial anti-cancer drug and is widely used for the treatment of various carcinomas, including gastric cancer (GC). The resistance of GC cells to 5-FU is still a matter of great concern.

OBJECTIVE

To illustrate the role of PI3K/Akt/mTOR signaling in regulating the cell cycle progression and migration of 5-FU-resistant GC cells.

MATERIAL AND METHODS

After the establishment of drug-resistant GC cell lines, the effects of 5-FU and/or BEZ235 (the dual inhibitor of PI3K and mTOR) on the activity of parental or drug-resistant GC cells were explored. The viability and localization of GC cells (MKN-45 and MKN-74) and their drug-resistant cells (MKN-45/R and MKN-74/R) were assessed using MTT assays and immunofluorescence staining. The impacts of 5-FU and/or BEZ235 on GC cell cycle progression and cell migration were assessed via flow cytometry analyses and wound healing assays, respectively. GC tissues were collected from patients with GC sensitive or refractory to 5-FU chemotherapy. RT-qPCR and western blot were conducted to measure PI3K, AKT, and mTOR levels in GC cells or tissues.

RESULTS

After 5-FU treatment, GC cells displayed 5-FU resistance and the viability of drug-resistant cells (MKN-45/R and MKN-74/R) was higher than that of parental cells (MKN-45 and MKN-74). The IC50 values for MKN-45 and MKN-45/R were 8.93 ug/ml and 140 ug/ml, and the values for MKN-74 and MKN-74/R were 3.93 ug/ml and 114.29 ug/ml. Additionally, the PI3K/Akt/mTOR signaling pathway was activated in drug-resistant GC cells and tumor tissues of patients refractory to 5-FU chemotherapy, as evidenced by high PI3K, Akt, and mTOR levels in MKN-45/R, MKN-74/R, and GC tissues resistant to 5-FU. BEZ235 promoted cell cycle arrest and suppressed the migration of GC cells. Moreover, the combination of BEZ235 and 5-FU led to more effective suppressive influence on cell cycle progression and cell migration relative to the single 5-FU or BEZ235 treatment.

CONCLUSIONS

Silencing of the PI3K/Akt/mTOR signaling pathway suppressed the 5-FU resistance of GC cells.

Pancreatic cancer stemness: dynamic status in malignant progression

Pancreatic cancer (PC) is one of the most aggressive malignancies worldwide. Increasing evidence suggests that the capacity for self-renewal, proliferation, and differentiation of pancreatic cancer stem cells (PCSCs) contribute to major challenges with current PC therapies, causing metastasis and therapeutic resistance, leading to recurrence and death in patients. The concept that PCSCs are characterized by their high plasticity and self-renewal capacities is central to this review. We focused specifically on the regulation of PCSCs, such as stemness-related signaling pathways, stimuli in tumor cells and the tumor microenvironment (TME), as well as the development of innovative stemness-targeted therapies. Understanding the biological behavior of PCSCs with plasticity and the molecular mechanisms regulating PC stemness will help to identify new treatment strategies to treat this horrible disease.

Anti-apoptotic effect of HeidihuangWan in renal tubular epithelial cells via PI3K/Akt/mTOR signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Heidihuang Wan (HDHW) is a classic Chinese herbal formula, which was first recorded in the "Suwen Bingji Qiyi Baoming Collection" written by Liu Wansu during the Jin Dynasty (1115-1234 AD). It is commonly used clinically for the treatment of kidney diseases and its curative effect is stable. Previous animal experiments have confirmed that HDHW can effectively improve renal fibrosis. However, the underlying pharmacological mechanism remains unclear.

AIMS OF THIS STUDY

Renal tubular epithelial cell (RTEC) apoptosis is one of the main pathological features of renal fibrosis. This study aimed to observe the effect and underlying mechanism of HDHW on the apoptosis of RTECs to further explore the pathological mechanism of HDHW against renal fibrosis.

MATERIALS AND METHODS

We examined the HDHW composition in rat serum. In vitro, we first screened out the optimal intervention concentration of HDHW on RTECs using the MTT assay. Hypoxia/reoxygenation was then used to induce apoptosis of RTECs (H/R-RTECs), which were divided into H/R-RTEC, astragaloside IV (positive control), HDHW, and RTECs groups. After 48 h of drug intervention, apoptosis of RTECs was detected using flow cytometry and protein expression was detected by western blotting. The 5/6 nephrectomy rat model was constructed and divided into the normal control, 5/6 nephrectomy, HDHW, and astragaloside IV groups. After 8 weeks of treatment, TUNEL staining was used to detect cell apoptosis, and western blotting was used to detect protein expression.

RESULTS

HDHW downregulated the expression of pro-apoptotic proteins Bax and Caspase3, up-regulated the expression of anti-apoptotic protein Bcl-2, activated the PI3K/Akt/mTOR signaling pathway, and reversed the early apoptosis of RTECs, thereby resisting the apoptosis of RTECs.

CONCLUSION

HDHW inhibits apoptosis of RTECs by modulating the PI3K/Akt/mTOR signaling pathway. This study provides experimental evidence for the anti-fibrotic effect of HDHW on the kidneys and partially elucidates its pharmacological mechanism of action.