Targeting TAK1 to overcome cisplatin resistance in lung adenocarcinoma by rewiring the NF-κB and p53 signaling.

LAPTM4B promotes gefitinib resistance and tumor stemness in non-small cell lung cancer by stabilizing RPS3 through inhibiting its ubiquitination.

Gefitinib resistance remains a major obstacle to the effective treatment of non-small cell lung cancer (NSCLC), and the underlying molecular mechanisms have not yet been fully elucidated. Lysosomal-associated transmembrane protein 4B (LAPTM4B) has been shown to be involved in cancer progression, but its specific role in gefitinib resistance and the prognosis of NSCLC patients remains unclear. In this study, we conducted functional experiments including CCK-8, Transwell, and tumor sphere formation assays in LAPTM4B-overexpressing or knockdown HCC827 cells and gefitinib-resistant HCC827-R cells. In vivo validation was performed using a NSCLC xenograft model in nude mice. The results showed that LAPTM4B was upregulated in NSCLC, with a further increase in gefitinib-resistant NSCLC samples. Functional experiments demonstrated that knockdown or overexpression of LAPTM4B regulated gefitinib resistance, cell migration, and stemness in HCC827 cells. Furthermore, RPS3 was identified as a key interacting target of LAPTM4B, and LAPTM4B could enhance the stability of RPS3 protein by inhibiting its ubiquitination. In vivo xenograft experiments showed that knockdown of LAPTM4B significantly suppressed tumor growth and tumor stemness, and this inhibitory effect could be reversed by overexpression of RPS3. Collectively, our findings indicate that LAPTM4B promotes gefitinib resistance and NSCLC progression by stabilizing RPS3 protein through inhibiting its ubiquitination, and the LAPTM4B-RPS3 axis may serve as a potential therapeutic target for overcoming gefitinib resistance in NSCLC.

Activation of the NF-κB/ALDH1A1 signaling promotes non-mutational resistance to EGFR-TKIs in non-small cell lung cancer

Acquired resistance to tyrosine kinase inhibitors (TKIs) remains a major clinical challenge in the treatment of EGFR-mutant non-small cell lung cancer (NSCLC). This study established TKI-resistant variants by integrating cell lines, lung cancer organoids (LCOs), and in vivo models, revealing the pivotal role of the NF-κB/ALDH1A1 signaling in mediating non-mutational TKI resistance. Resistant cells exhibited elevated RELA phosphorylation, enhanced ALDH1A1 expression and enzymatic activity, and stem-like properties. Mechanistically, NF-κB activation occurred as an early response to TKI exposure and promoted ALDH1A1 transcription via RELA. In turn, ALDH1A1 contributed to the sustained activation of NF-κB signaling, forming a self-reinforcing positive feedback loop. Genetic ALDH1A1 or RELA silencing reversed the resistant phenotype. Pharmacologically, treatment with an EGFR-TKI and the ALDH1A1 inhibitor disulfiram or the NF-κB-targeting agent EGCG synergistically restored the antitumor efficacy of TKIs both in vitro and in vivo. These findings establish the NF-κB/ALDH1A1 signaling as a key non-genetic mechanism of acquired EGFR-TKI resistance and provide a rational combination strategy to overcome it. Catalysis-dependent NF-κB–ALDH1A1 feedback loop drives non-mutational EGFR-TKI resistance. EGFR-TKI treatment suppresses EGFR signaling but rapidly induces NF-κB activation as an early event under TKI stress in EGFR-mutant NSCLC cells. Activated NF-κB (p-RELA) drives ALDH1A1 transcription, while ALDH1A1 enzymatic activity reinforces NF-κB signaling via IKKβ phosphorylation, forming a catalysis-dependent positive feedback loop that sustains stemness and promotes non-mutational TKI resistance. Disruption of this axis by inhibiting ALDH1A1 (DSF) or NF-κB (EGCG) restores TKI sensitivity. Catalysis-dependent NF-κB–ALDH1A1 feedback loop drives non-mutational EGFR-TKI resistance. EGFR-TKI treatment suppresses EGFR signaling but rapidly induces NF-κB activation as an early event under TKI stress in EGFR-mutant NSCLC cells. Activated NF-κB (p-RELA) drives ALDH1A1 transcription, while ALDH1A1 enzymatic activity reinforces NF-κB signaling via IKKβ phosphorylation, forming a catalysis-dependent positive feedback loop that sustains stemness and promotes non-mutational TKI resistance. Disruption of this axis by inhibiting ALDH1A1 (DSF) or NF-κB (EGCG) restores TKI sensitivity.

NKD1 promotes the progression and 5-FU resistance of colorectal cancer via the Wnt/β-catenin signaling.

5-Fluorouracil (5-FU) resistance continues to pose a considerable barrier in the postoperative management of advanced colorectal cancer (CRC). This study identified Naked cuticle homolog 1 (NKD1) as a key factor associated with 5-FU resistance in CRC based on sequencing data from the GEO and TCGA databases. Elevated NKD1 expression correlated with adverse clinicopathological features and poor patient survival. Functional assays revealed that NKD1 overexpression elevated the IC50 of 5-FU, promoted tumor cell proliferation, and attenuated apoptosis in both drug-treated and untreated settings. Additionally, NKD1 promoted CRC cell migration and invasion, regulated tumor stem cell markers. Mechanistically, NKD1 stabilizes DVL protein, regulates APC and FZD7, and fosters nuclear accumulation of β-catenin, initiating transcriptional programs downstream of Wnt signaling. Silencing NKD1 synergized with 5-FU to improve therapeutic efficacy in patient-derived organoid and xenograft models. These results establish NKD1 as a key regulator of CRC malignancy and chemoresistance via Wnt/β-catenin pathway activation, supporting its potential as a dual biomarker and therapeutic target in combination regimens.

A three-gene signature correlated with MAPK/ERK activation characterizes acquired resistance to EGFR-tyrosine kinase inhibitors in non-small cell lung cancer

Epidermal growth factor receptor-targeted therapies such as afatinib provide clinical benefits to patients with advanced-stage non-small cell lung cancer (NSCLC); however, acquired resistance frequently develops, with the underlying mechanisms remaining undefined in 20–30% of cases. The present study established afatinib-resistant (AR) NSCLC cell lines and confirmed their resistance phenotype using Cell Counting Kit-8 (CCK-8) cell viability assays. Notably, these cells also exhibited cross-resistance to osimertinib. To elucidate the molecular basis of resistance acquisition, the time-resolved transcriptomic profiling of A549 cells was performed across three stages: Parental, afatinib-exposed (adaptive phase) and stable resistant cells. The analyzed results revealed the persistent upregulation of ABLIM3, HTR1D and HSPA1A, which was validated by reverse transcription-quantitative polymerase chain reaction. The meta-analysis of hazard ratios from The Cancer Genome Atlas demonstrated that the elevated expression level of the three-gene signature was significantly associated with tumor progression and an increased risk of disease recurrence. These transcriptional alterations were accompanied by the sustained activation of the MAPK/ERK signaling pathway, as evidenced by increased ERK1/2 phosphorylation detected using western blot analysis, which was positively associated with the expression level of the three-gene signature. Functional analyses further demonstrated that the pharmacological inhibition of MAPK/ERK signaling using selumetinib effectively re-sensitized AR cells to both afatinib and osimertinib, as demonstrated by restored drug sensitivity in CCK-8 assays. Collectively, these findings suggest that MAPK/ERK signaling contributes to the transition from adaptive tolerance to stable resistance to afatinib and highlight a tractable therapeutic vulnerability for overcoming resistance to tyrosine kinase inhibitors in NSCLC.

Luteolin reverses chemoresistance in colorectal cancer cells via TET1/TDG-dependent epigenetic repression of β-catenin.

Resistance to 5-fluorouracil (5-FU) and oxaliplatin (OXT) remains a major cause of treatment failure in colorectal cancer (CRC). Luteolin, a dietary flavonoid with anticancer properties, has shown therapeutic potential in various malignancies, but its effects on chemotherapy-resistant CRC remain poorly understood. In this study, we investigated whether luteolin restores chemosensitivity in 5-FU-resistant (SNUC5/5-FUR) and OXT-resistant (SNUC5/OXTR) CRC cells and explored the underlying molecular mechanisms. Luteolin reduced cell viability and induced apoptosis in both resistant cell lines. Mechanistically, luteolin suppressed β-catenin expression by downregulating ten-eleven translocation (TET) proteins, increasing DNA methyltransferase (DNMT) expression, enhancing CpG methylation, and reducing TET1 occupancy at the β-catenin promoter. Luteolin also decreased thymine DNA glycosylase (TDG) expression, disrupted the TET1/TDG interaction, and reduced TDG recruitment to the β-catenin promoter. Consistently, knockdown of either TET1 or TDG decreased β-catenin expression, while luteolin further enhanced apoptosis in siTET1- or siTDG-transfected resistant cells. Additionally, luteolin attenuated intracellular reactive oxygen species accumulation and potentiated the cytotoxic effects of 5-FU and OXT in resistant CRC cells. These findings demonstrate that luteolin reverses chemoresistance by suppressing the TET1/TDG-β-catenin axis through epigenetic regulation and modulation of intracellular redox homeostasis, supporting its potential as an adjuvant for CRC chemotherapy.

DHCR24+ tumor epithelial cells drive cisplatin resistance in bladder cancer by enhancing cholesterol metabolism to activate lipid raft-associated MAPK signaling.