The role of non-apoptotic cell death in the treatment and drug-resistance of digestive tumors

Multi-Pathway Study for Oxaliplatin Resistance Reduction

Chemotherapy for cancer frequently uses platinum-based medications, including oxaliplatin, carboplatin, and cisplatin; however, due to their high systemic toxicity, lack of selectivity, drug resistance, and other side effects, platinum-based medications have very limited clinical application. As a first-line medication in antitumor therapy, oxaliplatin must be administered to minimize side effects while achieving anticancer objectives. A new CDC7 inhibitor called XL413 has demonstrated promising antitumor therapeutic effects in a variety of malignant tumors and may have anticancer properties. This offers a fresh viewpoint on how to lessen oxaliplatin resistance and, specifically, increase the potency of already prescribed anticancer therapies. In this paper, the current developments in anticancer therapy are discussed, along with the many mechanisms of oxaliplatin's antitumor effects, clinical treatment challenges, and related approaches. We conducted more research on oxaliplatin resistance that arose during chemotherapy and searched for ways to lessen it in order to enhance its chemotherapeutic performance. Ultimately, we studied how distinct resistance routes relate to one another. Meanwhile, XL413, a novel CDC7 inhibitor, offers a perspective on the possibilities for developing treatment approaches for this innovation point. The search terms "Oxaliplatin, XL413, drug resistance, cancer treatment," etc., were applied in the X-MOL and PubMed databases for this review's literature search. Boolean logic was then employed to maximize the search approach. These databases can offer thorough research data and cover a broad range of biological publications. Excluded publications were works of low relevance, duplicates, or those with insufficient information. The mechanism of oxaliplatin's anticancer effect, oxaliplatin resistance and its amelioration, and the role of XL413 in oxaliplatin treatment were the main topics of the 140 publications that were ultimately included for analysis.

Cephaeline promotes ferroptosis by targeting NRF2 to exert anti-lung cancer efficacy

CONTEXT

Cephaeline is a natural product isolated from ipecac (Cephaelis ipecacuanha [Brot.] A. Rich. [Rubiaceae]). It exhibits promising anti-lung cancer activity and ferroptosis induction may be a key mechanism for its anti-lung cancer effect.

OBJECTIVES

This study investigates the anti-lung cancer activity and mechanisms of cephaeline both in vitro and in vivo.

MATERIALS AND METHODS

H460 and A549 lung cancer cells were used. The cephaeline inhibition rate on lung cancer cells was detected via a Cell Counting Kit-8 assay after treatment with cephaeline for 24 h. Subsequently, the concentrations of 25, 50 and 100 nM were used for in vitro experiments. In addition, the antitumour effects of cephaeline (5, 10 mg/kg) in vivo were evaluated after 12 d of cephaeline treatment.

RESULTS

Cephaeline showed significant inhibitory effects on lung cancer cells, and the IC50 of cephaeline on H460 and A549 at 24, 48 and 72 h were 88, 58 and 35 nM, respectively, for H460 cells and 89, 65 and 43 nM, respectively, for A549 cells. Meanwhile, we demonstrated that ferroptosis is the key mechanism of cephaeline against lung cancer. Finally, we found that cephaeline induced ferroptosis in lung cancer cells by targeting NRF2.

DISCUSSION AND CONCLUSION

We demonstrated for the first time that cephaeline inhibits NRF2, leading to ferroptosis in lung cancer cells. These findings may contribute to the development of innovative therapeutics for lung cancer.

Proton Sponge Nanocomposites for Synergistic Tumor Elimination via Autophagy Inhibition-Promoted Cell Apoptosis and Macrophage Repolarization-Enhanced Immune Response

Cytoprotective autophagy and an immunosuppressive tumor microenvironment (TME) are two positive promoters for tumor proliferation and metastasis that severely hinder therapeutic efficacy. Inhibiting autophagy and reconstructing TME toward macrophage activation simultaneously are of great promise for effective tumor elimination, yet are still a huge challenge. Herein, a kind of dendrimer-based proton sponge nanocomposites was designed and constructed for tumor chemo/chemodynamic/immunotherapy through autophagy inhibition-promoted cell apoptosis and macrophage repolarization-enhanced immune response. These obtained nanocomposites contain a proton sponge G5AcP dendrimer, a Fenton-like agent Cu(II), and chemical drug doxorubicin (DOX). When accumulated in tumor regions, G5AcP can act as an immunomodulator to realize deacidification-promoted macrophage repolarization toward antitumoral type, which then secretes inflammatory cytokines to activate T cells. They also regulate intracellular lysosomal pH to inhibit cytoprotective autophagy. The released Cu(II) and DOX can induce aggravated damage through a Fenton-like reaction and chemotherapeutic effect in this autophagy-inhibition condition. Tumor-associated antigens are released from these dying tumor cells to promote the maturity of dendritic cells, further activating T cells. Effective tumor elimination can be achieved by this dendrimer-based therapeutic strategy, providing significant guidance for the design of a promising antitumor nanomedicine.

The role of autophagy in hypoxia-induced radioresistance

Radiotherapy is a widely used treatment modality against cancer, and although survival rates are increasing, radioresistant properties of tumours remain a significant barrier for curative treatment. Tumour hypoxia is one of the main contributors to radioresistance and is common in most solid tumours. Hypoxia is responsible for many molecular changes within the cell which helps tumours to survive under such challenging conditions. These hypoxia-induced molecular changes are predominantly coordinated by the hypoxia inducible factor (HIF) and have been linked with the ability to confer resistance to radiation-induced cell death. To overcome this obstacle research has been directed towards autophagy, a cellular process involved in self degradation and recycling of macromolecules, as HIF plays a large role in its coordination under hypoxic conditions. The role that autophagy has following radiotherapy treatment is conflicted with evidence of both cytoprotective and cytotoxic effects. This literature review aims to explore the intricate relationship between radiotherapy, hypoxia, and autophagy in the context of cancer treatment. It provides valuable insights into the potential of targeting autophagy as a therapeutic strategy to improve the response of hypoxic tumours to radiotherapy.

Biological function and clinical application prospect of tsRNAs in digestive system biology and pathology

tsRNAs are small non-coding RNAs originating from tRNA that play important roles in a variety of physiological activities such as RNA silencing, ribosome biogenesis, retrotransposition, and epigenetic inheritance, as well as involvement in cellular differentiation, proliferation, and apoptosis. tsRNA-related abnormalities have a significant influence on the onset, development, and progression of numerous human diseases, including malignant tumors through affecting the cell cycle and specific signaling molecules. This review introduced origins together with tsRNAs classification, providing a summary for regulatory mechanism and physiological function while dysfunctional effect of tsRNAs in digestive system diseases, focusing on the clinical prospects of tsRNAs for diagnostic and prognostic biomarkers. Video Abstract.

Knockdown of BAP31 Overcomes Hepatocellular Carcinoma Doxorubicin Resistance through Downregulation of Survivin

The expression of B-cell receptor associated protein 31 (BAP31) is increased in many tumor types, and it is reported to participate in proliferation, migration, and apoptosis. However, the relationship between BAP31 and chemoresistance is uncertain. This study investigated the role of BAP31 in regulating the doxorubicin (Dox) resistance of hepatocellular carcinoma (HCC). The expression of proteins was assessed by Western blotting. The correlation between BAP31 expression and Dox resistance was examined by MTT and colony formation assays. Apoptosis was analyzed by flow cytometry and TdT-mediated dUTP nick end labeling assays. Western blot and immunofluorescence analyses were performed in the knockdown cell lines to explore the possible mechanisms. In this study, BAP31 was strongly expressed, and knockdown of BAP31 increased Dox chemosensitivity in cancer cells. Furthermore, the expression of BAP31 was higher in the Dox-resistant HCC cells than that in their parental cells; knockdown of BAP31 reduced the half maximal inhibitory concentration value and overcame Dox resistance in Dox-resistant HCC cells. In HCC cells, knockdown of BAP31 increased Dox-induced apoptosis and enhanced Dox chemosensitivity in vitro and in vivo. The potential mechanism by which BAP31 increased Dox-induced apoptosis is that BAP31 inhibited survivin expression by promoting FoxO1 nucleus-cytoplasm translocation. Knockdown of BAP31 and survivin had a synergistic effect on Dox chemosensitivity by enhancing the apoptosis of HCC cells. These findings reveal that BAP31 knockdown enhances Dox chemosensitivity through the downregulation of survivin, suggesting that BAP31 is a potential therapeutic target for improving the treatment response of HCC with resistance to Dox.

LINC00511, a future star for the diagnosis and therapy of digestive system malignant tumors

The digestive system malignant tumors (DSMTs), mainly consist of digestive tract and digestive gland tumors, become an inescapable culprit to hazard human health worldwide. Due to the huge hysteresis in the cognitive theories of DSMTs occurrence and progression, advances in medical technology have not improved the prognosis. Therefore, more studies on a variety of tumor-associated molecular biomarkers and more detailed disclosure on potential regulatory networks are urgently needed to facilitate the diagnostic and therapeutic strategies of DSMTs. With the development of cancer bioinformatics, a special type of endogenous RNA involved in multi-level cellular function regulation rather than encoding protein, is categorized as non-coding RNAs (ncRNAs) and becomes a hotspot issue in oncology. Among them, long non-coding RNAs (lncRNAs), transcription length > 200 nt, show obvious superiority in both research quantity and dimension compared to microRNAs (miRNAs) and circular RNAs (circRNAs). As a recently discovered lncRNA, LINC00511 has been confirmed to be closely associated with DSMTs and might be exploited as a novel biomarker. In the present review, the comprehensive studies of LINC00511 in DSMTs are summarized, as well as the underlying molecular regulatory networks. In addition, deficiencies in researches are point out and discussed. The Cumulative oncology studies provide a fully credible theoretical basis for identifying the regulatory role of LINC00511 in human DSMTs. LINC00511, proved to be an oncogene in DSMTs, might be defined as a potential biomarker for diagnosis and prognosis evaluation, as well as a rare therapeutic target.

Overcoming cancer chemotherapy resistance by the induction of ferroptosis

Development of resistance to chemotherapy in cancer continues to be a major challenge in cancer management. Ferroptosis, a unique type of cell death, is mechanistically and morphologically different from other forms of cell death. Ferroptosis plays a pivotal role in inhibiting tumour growth and has presented new opportunities for treatment of chemotherapy-insensitive tumours in recent years. Emerging studies have suggested that ferroptosis can regulate the therapeutic responses of tumours. Accumulating evidence supports ferroptosis as a potential target for chemotherapy resistance. Pharmacological induction of ferroptosis could reverse drug resistance in tumours. In this review article, we first discuss the key principles of chemotherapeutic resistance in cancer. We then provide a brief overview of the core mechanisms of ferroptosis in cancer chemotherapeutic drug resistance. Finally, we summarise the emerging data that supports the fact that chemotherapy resistance in different types of cancers could be subdued by pharmacologically inducing ferroptosis. This review article suggests that pharmacological induction of ferroptosis by bioactive compounds (ferroptosis inducers) could overcome chemotherapeutic drug resistance. This article also highlights some promising therapeutic avenues that could be used to overcome chemotherapeutic drug resistance in cancer.

Anoikis-related genes combined with single cell sequencing: Insights into model specification of lung adenocarcinoma and applicability for prognosis and therapy

Background: Anoikis has therapeutic potential against different malignancies including lung adenocarcinoma. This study used anoikis and bioinformatics to construct a prognostic model for lung adenocarcinoma and explore new therapeutic strategies. Methods: Several bioinformatic algorithms (co-expression analysis, univariate Cox analysis, multivariate Cox analysis, and cross-validation) were used to screen anoikis-related genes (ARGs) to construct a risk model. Lung adenocarcinoma patients were divided into training and testing groups at a ratio of 1:1. The prognostic model was validated by risk score comparison between high- and low-risk groups using receiver operating characteristic curve (ROC), nomograms, independent prognostic analysis and principal component analysis. In addition, two anoikis-related genes patterns were classified utilizing consensus clustering method and were compared with each other in survival time, immune microenvironment, and regulation in pathway. Single cell sequencing was applied to analyze anoikis-related genes constructed the model. Results: This study demonstrated the feasibility of the model based on seven anoikis-related genes, as well as identifying axitinib, nibtinib and sorafenib as potential therapeutic strategies for LUAD. Risk score based on this model had could be used as an independent prognostic factor for lung adenocarcinoma (HR > 1; p < 0.001) and had the highest accuracy to predict survival compared with the clinical characteristics. Single cell sequencing analysis discovered Keratin 14 (KRT14, one of the seven anoikis-related genes) was mainly expressed in malignant cells in various cancers. Conclusion: We identified seven anoikis-related genes and constructed an accurate risk model based on bioinformatics analysis that can be used for prognostic prediction and for the design of therapeutic strategies in clinical practice.

Pyroptosis: a novel signature to predict prognosis and immunotherapy response in gliomas

Gliomas are the most common primary brain tumors and are highly malignant with a poor prognosis. Pyroptosis, an inflammatory form of programmed cell death, promotes the inflammatory cell death of cancer. Studies have demonstrated that pyroptosis can promote the inflammatory cell death (ICD) of cancer, thus affecting the prognosis of cancer patients. Therefore, genes that control pyroptosis could be a promising candidate bio-indicator in tumor therapy. The function of pyroptosis-related genes (PRGs) in gliomas was investigated based on the Chinese Glioma Genome Atlas (CGGA), the Cancer Genome Atlas (TCGA) and the Repository of Molecular Brain Neoplasia Data (Rembrandt) databases. In this study, using the non-negative matrix factorization (NMF) clustering method, 26 PRGs from the RNA sequencing data were divided into two subgroups. The LASSO and Cox regression was used to develop a 4-gene (BAX, Caspase-4, Caspase-8, PLCG1) risk signature, and all glioma patients in the CGGA, TCGA and Rembrandt cohorts were divided into low- and high-risk groups. The results demonstrate that the gene risk signature related to clinical features can be used as an independent prognostic indicator in glioma patients. Moreover, the high-risk subtype had rich immune infiltration and high expression of immune checkpoint genes in the tumor immune microenvironment (TIME). The analysis of the Submap algorithm shows that patients in the high-risk group could benefit more from anti-PD1 treatment. The risk characteristics associated with pyroptosis proposed in this study play an essential role in TIME and can potentially predict the prognosis and immunotherapeutic response of glioma patients.

Synergistic chemo-photothermal and ferroptosis therapy of polydopamine nanoparticles for esophageal cancer

Aim: To develop synergistic chemo-photothermal and ferroptosis therapy nanoparticles to improve the efficacy of treatment for esophageal cancer. Materials & methods: Fe₃O₄@PDA-HCPT nanoparticles (NPs) were constructed and characterized. Their synergistic antitumor effects were evaluated in EC1 and EC109 esophageal cancer cells as well as in esophageal cancer-bearing mice. Results: In vitro and in vivo experiments showed that Fe₃O₄@PDA-HCPT NPs exhibited significant tumor inhibition and excellent diagnostic properties. The killing ability of tumor cells was significantly enhanced after irradiation. Conclusion: Synergistic application of the three therapies effectively inhibited tumor growth and exhibited potent antitumor effects, providing strong support for developing nanoparticles with synergistic antitumor effects of multiple therapies.

BI 2536 induces gasdermin E-dependent pyroptosis in ovarian cancer

Background

The frequent emergence of drug resistance to chemotherapy is a major obstacle for the treatment of ovarian cancer. There is a need for novel drugs to fulfill this challenge. Pyroptosis-inducing drugs can inhibit tumor growth. However, their roles in ovarian cancer have not been demonstrated.

Methods

We tested the effectiveness of a novel drug, BI 2536, which we found in colorectal cancer. Cell proliferation, cell cycle, and drug-induced apoptosis and pyroptosis were tested. In vivo treatments were performed using a cell-derived xenograft model.

Results

BI 2536 significantly inhibited the proliferation of ovarian cancer cells and induced cell cycle arrest at the G2/M phases. After BI 2536 treatment, DNA fragmentation and PS exposure on the outside of apoptotic cells were detected. Moreover, the pyroptotic phenotype of ovarian cancer cells along with the release of LDH and HMGB1 were observed, indicating the leakage of cells. Western blot analysis verified that BI 2536 induced GSDME-mediated pyroptosis. Pyroptosis was abolished after additional treatment with Z-DEVD-FMK, a caspase-3 inhibitor. Thus, BI 2536 induced pyroptosis in ovarian cancer through the caspase-3/GSDME pathway. In vivo experiments further demonstrated the antitumoral effect and ability of BI 2536 to accumulate CD8⁺ T cells in ovarian cancer.

Conclusion

In this study, we identified BI 2536 as an effective anti-ovarian cancer drug that inhibits proliferation, arrests the cell cycle, induces apoptosis and pyroptosis, and leads to the accumulation of CD8⁺ T cells in tumor sites. Drug-induced pyroptosis may have promising prospects for reducing side effects and activating immune responses.

Berberine as a Potential Anticancer Agent: A Comprehensive Review

Berberine (BBR), a potential bioactive agent, has remarkable health benefits. A substantial amount of research has been conducted to date to establish the anticancer potential of BBR. The present review consolidates salient information concerning the promising anticancer activity of this compound. The therapeutic efficacy of BBR has been reported in several studies regarding colon, breast, pancreatic, liver, oral, bone, cutaneous, prostate, intestine, and thyroid cancers. BBR prevents cancer cell proliferation by inducing apoptosis and controlling the cell cycle as well as autophagy. BBR also hinders tumor cell invasion and metastasis by down-regulating metastasis-related proteins. Moreover, BBR is also beneficial in the early stages of cancer development by lowering epithelial-mesenchymal transition protein expression. Despite its significance as a potentially promising drug candidate, there are currently no pure berberine preparations approved to treat specific ailments. Hence, this review highlights our current comprehensive knowledge of sources, extraction methods, pharmacokinetic, and pharmacodynamic profiles of berberine, as well as the proposed mechanisms of action associated with its anticancer potential. The information presented here will help provide a baseline for researchers, scientists, and drug developers regarding the use of berberine as a promising candidate in treating different types of cancers.

LINC00963/miR-4458 regulates the effect of oxaliplatin in gastric cancer by mediating autophagic flux through targeting of ATG16L1

Oxaliplatin resistance is the greatest obstacle to the management of local recurrence in gastric cancer patients after surgery. Accumulating evidence has suggested that inhibiting autophagy may be a novel approach for reversing resistance to oxaliplatin treatment. In this manuscript, we aimed to investigate the role of LINC00963 in regulating autophagy and oxaliplatin resistance. qRT-PCR, immunochemistry staining, and western blotting were used to detect gene expression. Plasmids were used to up- and downregulate the expression of LINC00963 and miR-4458. A caspase 3/7 activity kit and flow cytometry were used to detect the apoptosis rate. CCK8 and Transwell assays were used to test cell proliferation and migration, respectively. Transmission electron microscopy and a dual fluorescent lentivirus autophagy system were used to evaluate autophagic flux. Dual luciferase reporter gene assays and RNA pulldown assays were used to evaluate the potential crosstalk. LINC00963 was highly expressed in gastric cancer patients and cell lines. In addition, high LINC00963 expression was found to be associated with poor prognosis and local recurrence in gastric cancer patients, indicating that LINC00963 might be involved in oxaliplatin resistance. Moreover, we found that LINC00963 was aberrantly highly expressed in oxaliplatin-resistant SGC-7901 (SGC-7901-R) cells and promoted proliferation and migration and reduced the apoptosis rate in SGC-7901-R cells. Furthermore, among all potential target microRNAs, miR-4458 was found to be negatively regulated by LINC00963 both in vivo and in vitro. In addition, miR-4458 overexpression led to impaired proliferation and migration and enhanced cell apoptosis and G1 arrest in SGC-7901-R cells. Further RNA pulldown and dual luciferase reporter gene assays indicated the interaction between LINC00963 and miR-4458. Moreover, we found enhanced autophagic flux in SGC-7901-R cells compared with SGC-7901 cells; in addition, an inhibitor of autophagy induced apoptosis in SGC-7901-R cells. Then, we found that downregulation of LINC00963 expression and upregulation of miR-4458 expression significantly suppressed autophagic flux in SGC-7901-R cells. Based on starBase V3.0 and dual luciferase reporter gene assays, we predicted and confirmed that ATG16L1 might be the target of miR-4458 to regulate autophagy. In conclusion, LINC00963 and miR-4458 are potential biomarkers for predicting the overall survival of gastric cancer patients. Moreover, targeting LINC00963 to inhibit autophagic flux sensitizes gastric cancer cells to oxaliplatin treatment, suggesting that it is a potential novel therapeutic target for improving oxaliplatin sensitivity.