Downregulation of ABCC3 activates MAPK signaling through accumulation of deoxycholic acid in colorectal cancer cells.

ABCC3 (also known as MRP3) is an ATP binding cassette transporter for bile acids, whose expression is downregulated in colorectal cancer through the Wnt/ß-catenin signaling pathway. However, it remained unclear how downregulation of ABCC3 expression contributes to colorectal carcinogenesis. We explored the role of ABCC3 in the progression of colorectal cancer-in particular, focusing on the regulation of bile acid export. Gene expression analysis of colorectal adenoma isolated from familial adenomatous polyposis patients revealed that genes related to bile acid secretion including ABCC3 were downregulated as early as at the stage of adenoma formation. Knockdown or overexpression of ABCC3 increased or decreased intracellular concentration of deoxycholic acid, a secondary bile acid, respectively, in colorectal cancer cells. Forced expression of ABCC3 suppressed deoxycholic acid-induced activation of MAPK signaling. Finally, we found that nonsteroidal anti-inflammatory drugs increased ABCC3 expression in colorectal cancer cells, suggesting that ABCC3 could be one of the targets for therapeutic intervention of familial adenomatous polyposis. Our data thus suggest that downregulation of ABCC3 expression contributes to colorectal carcinogenesis through the regulation of intracellular accumulation of bile acids and activity of MAPK signaling.

Detection of Extracellular Vesicle-Derived RNA as Potential Prostate Cancer Biomarkers: Role of Cancer-type SLCO1B3 and ABCC3.

Extracellular vesicles (EVs) provide a minimally invasive liquid biopsy source of tumor-specific markers for patients who have already undergone prostatectomies. Our laboratory has previously demonstrated enrichment of the cancer-type solute carrier organic anion transporter family 1B3 (ct-SLCO1B3) and the ATP Binding Cassette Subfamily Member C (ABCC3) in castration-resistant cell lines (CRPC). However, their expression in EVs has yet to be explored. Our study demonstrated that ct-SLCO1B3 and ABCC3 are highly detectable in CRPC cell line-derived EVs. We also showed that ct-SLCO1B3 and ABCC3 were detectable in a CRPC xenograft mouse model, both intratumorally and in plasma-derived EVs. Our results provide evidence for EV-contained ct-SLCO1B3 and ABCC3 as novel, EV-based tumor markers for prostate cancer progression.

Identification of ABCC3 and its isoforms as potential biomarker in hepatocellular carcinoma.

Liver diseases preceding the occurrence of hepatocellular carcinoma (HCC) play a crucial role in the progression and establishment of HCC, a malignancy ranked as the third deadliest cancer worldwide. Late diagnosis, alongside ineffective treatment, leads patients to a poor survival rate. This scenario argues for seeking novel alternatives for detecting liver alterations preceding the early occurrence of HCC. Experimental studies have reported that ABCC3 protein increases within HCC tumors but not in adjacent tissue. Therefore, we analyzed ABCC3 expression in public databases and investigated the presence of ABCC3 and its isoforms in plasma, urine and its release in extracellular vesicles (EVs) cargo from patients bearing cirrhosis and HCC. The UALCAN and GEPIA databases were used to analyze the expression of ABCC3 in HCC. The results were validated in a case-control study including 41 individuals bearing cirrhosis and HCC, and the levels of ABCC3 in plasma and urine samples, as well as EVs, were analyzed by ELISA and western blot. Our data showed that ABCC3 expression was higher in HCC tissues than in normal tissues and correlated with HCC grade and stage. ABCC3 protein levels were highly increased in both plasma and urine and correlated with liver disease progression and severity. The isoforms MRP3A and MRP3B of ABCC3 were significantly increased in both EVs and plasma/urine of patients bearing HCC. ABCC3 expression gradually increases in HCC tissues, and its protein levels are increased in both plasma and urine of patients with cirrhosis and HCC. MRP3A and MRP3B isoforms have the potential to be prognostic biomarkers of HCC.

Placing steroid hormones within the human ABCC3 transporter reveals a compatible amphiphilic substrate-binding pocket.

The human ABC transporter ABCC3 (also known as MRP3) transports a wide spectrum of substrates, including endogenous metabolites and exogenous drugs. Accordingly, it participates in multiple physiological processes and is involved in diverse human diseases such as intrahepatic cholestasis of pregnancy, which is caused by the intracellular accumulation of bile acids and estrogens. Here, we report three cryogenic electron microscopy structures of ABCC3: in the apo-form and in complexed forms bound to either the conjugated sex hormones ß-estradiol 17-(ß-D-glucuronide) and dehydroepiandrosterone sulfate. For both hormones, the steroid nuclei that superimpose against each other occupy the hydrophobic center of the transport cavity, whereas the two conjugation groups are separated and fixed by the hydrophilic patches in two transmembrane domains. Structural analysis combined with site-directed mutagenesis and ATPase activity assays revealed that ABCC3 possesses an amphiphilic substrate-binding pocket able to hold either conjugated hormone in an asymmetric pattern. These data build on consensus features of the substrate-binding pocket of MRPs and provide a structural platform for the rational design of inhibitors.

HOXC10 promotes carboplatin resistance of ovarian cancer by regulating ABCC3.

HOXC10 has been reported to be upregulated in ovarian cancer (OC) tissues, attributing to the metastasis of OC. However, the specific functions of HOXC10 in OC, especially its role in chemoresistance, remain to be determined. Therefore, in this study, we explored the function and the underlying mechanisms of HOXC10 in carboplatin resistance of OC. A variety of approaches were utilized to analyze the expression of HOXC10 and its related genes. The effect of HOXC10 in cell growth and chemoresistance was investigated in carboplatin-resistant OC subline TOV21G-R and the parental TOV21G-P cells. ROC curve and survival analysis were conducted to determine the predictive value of HOXC10 and ABCC3 combination in carboplatin resistance and the prognosis of OC. Luciferase reporter assay and Chromatin immunoprecipitation (ChIP) assay were used to explore the direct regulation of ß-catenin by HOXC10. Our results demonstrated that the expression of HOXC10 was upregulated both in the carboplatin-resistant OC tissues and TOV21G-R cells. Furthermore, the upregulation of HOXC10 could promote the expression of ABCC3 by transcriptionally upregulating ß-catenin. Moreover, overexpression of HOXC10 could decrease the sensitivity of cells to carboplatin, while knocking down HOXC10 had the opposite effect both in vitro and in vivo. Therefore, the expression of HOXC10/ABCC3 could be a novel biomarker for predicting the carboplatin resistance and the prognosis of OC patients.

SLCO4A1 expression is associated with activated inflammatory pathways in high-grade serous ovarian cancer.

Patients with high-grade serous ovarian cancer (HGSOC) have a very poor overall survival. Current therapeutic approaches do not bring benefit to all patients. Although genetic alterations and molecular mechanisms are well characterized, the molecular pathological conditions are poorly investigated. Solute carrier organic anion transporter family member 4A1 (SLCO4A1) encodes OATP4A1, which is an uptake membrane transporter of metabolic products. Its expression may influence various signaling pathways associated with the molecular pathophysiological conditions of HGSOC and consequently tumor progression. RNA sequencing of 33 patient-derived HGSOC cell lines showed that SLCO4A1 expression was diverse by individual tumors, which was further confirmed by RT-qPCR, Western blotting and immunohistochemistry. Gene Set Enrichment Analysis revealed that higher SLCO4A1 level was associated with inflammation-associated pathways including NOD-like receptor, adipocytokine, TALL1, CD40, NF-κB, and TNF-receptor 2 signaling cascades, while low SLCO4A1 expression was associated with the mitochondrial electron transport chain pathway. The overall gene expression pattern in all cell lines was specific to each patient and remained largely unchanged during tumor progression. In addition, genes encoding ABCC3 along with SLCO4A1-antisense RNA 1, were associated with higher expression of the SLCO4A1, indicating their possible involvement in inflammation-associated pathways that are downstream to the prostaglandin E2/cAMP axis. Taken together, increased SLCO4A1/OATP4A1 expression is associated with the upregulation of specific inflammatory pathways, while the decreased level is associated with mitochondrial dysfunction. These molecular pathophysiological conditions are tumor specific and should be taken into consideration by the development of therapies against HGSOC.

FAT1 downregulation enhances stemness and cisplatin resistance in esophageal squamous cell carcinoma.

Primary or acquired drug resistance accounts for the failure of chemotherapy and cancer recurrence in esophageal squamous cell carcinoma (ESCC). However, the aberrant mechanisms driving drug resistance are not fully understood in ESCC. In our previous study, FAT Atypical Cadherin 1 (FAT1) was found to inhibit the epithelial-mesenchymal transition (EMT) process in ESCC. EMT plays a critical role in the development of drug resistance in multiple cancer types. Besides, it equips cancer cells with cancer stem cell (CSC)-like characters that also are associated with chemotherapy resistance. Whether FAT1 regulates the stemness or drug resistance of ESCC cells is worth being explored. Here we found that FAT1 was downregulated in ESCC spheres and negatively correlated with stemness-associated markers including ALDH1A1 and KLF4. Knocking down FAT1 enhanced the sphere-forming ability, resistance to cisplatin and drug efflux of ESCC cells. Additionally, FAT1 knockdown upregulated the expression of drug resistance-related gene ABCC3. Furtherly, we found FAT1 knockdown induced the translocation of ß-catenin into nucleus and enhanced its transcriptional activity. The result of ChIP showed that ß-catenin was enriched in ABCC3 promoter. Furthermore, ß-catenin promoted expression of ABCC3. In conclusion, FAT1 knockdown might enhance the stemness and ABCC3-related cisplatin resistance of ESCC cells via Wnt/ß-catenin signaling pathway. FAT1 and its downstream gene ABCC3 might be potential targets for overcoming chemoresistance in ESCC.

Association Study of SLCO1B3 and ABCC3 Genetic Variants in Gallstone Disease.

There is growing evidence that gallstone formation may be genetically determined. Recent studies have shown that polymorphism of genes encoding proteins involved in bile acid transport may be associated with the risk of gallstone disease. The aim of this study was to investigate the association between SLCO1B3 (rs4149117:G>T, rs7311358:A>G) and ABCC3 (rs4793665:T>C, rs11568591:G>A) genetic variants and susceptibility to cholesterol gallstone disease, as well as gallstone composition. The study included 317 patients suffering from cholelithiasis who underwent cholecystostomy and 249 controls with no evidence of stones, confirmed by ultrasound examination. There were no statistically significant differences in the distribution of studied gene polymorphisms between patients with gallstone disease and healthy controls. No significant associations were observed between studied genotypes and the content of analyzed gallstone components: total cholesterol, bilirubin, CaCO3, nor the total bile acids. There was also no association between bile acid content in gallstones and the polymorphisms studied. The results of this study suggest that polymorphisms of SLCO1B3 and ABCC3 genes are not a valuable marker of gallstone disease susceptibility and do not influence gallstone composition.

Quercetin Regulates Key Components of the Cellular Microenvironment during Early Hepatocarcinogenesis.

Hepatocellular carcinoma (HCC) is a health problem worldwide due to its high mortality rate, and the tumor microenvironment (TME) plays a key role in the HCC progression. The current ineffective therapies to fight the disease still warrant the development of preventive strategies. Quercetin has been shown to have different antitumor activities; however, its effect on TME components in preneoplastic lesions has not been fully investigated yet. Here, we aimed to evaluate the effect of quercetin (10 mg/kg) on TME components during the early stages of HCC progression induced in the rat. Histopathological and immunohistochemical analyses showed that quercetin decreases the size of preneoplastic lesions, glycogen and collagen accumulation, the expression of cancer stem cells and myofibroblasts markers, and that of the transporter ATP binding cassette subfamily C member 3 (ABCC3), a marker of HCC progression and multi-drug resistance. Our results strongly suggest that quercetin has the capability to reduce key components of TME, as well as the expression of ABCC3. Thus, quercetin can be an alternative treatment for inhibiting the growth of early HCC tumors.

The implications of ABCC3 in cancer drug resistance: can we use it as a therapeutic target?

Drug resistance is one of the main causes of chemotherapy failure. Although several factors are involved in cancer drug resistant, the exporter pumps overexpression that mediates the drugs flow to outside the cells and reduces both the drugs intracellular concentration and effectiveness, has been one of the most important challenges. Overexpression of ABCC3, a member of the ABCC subfamily, has been strongly associated to the resistance to multiple drugs. ABCC3 has been found highly expressed in different types of cancers and is associated with poor prognosis and resistance to treatments. In this review, we summarize the molecular mechanisms involved in cancer drug resistance and discuss the current knowledge about the structure, function and role of ABCC3 in drug resistance, as well as, the expression status of ABCC3 in different types of cancer. We also provide evidences that place ABCC3 as a potential therapeutic target for improving the cancer treatment by focusing on the need of developing more effective cancer therapies to target ABCC3 in translational researches.

Loss of an ABC transporter in Arabidopsis thaliana confers hypersensitivity to the anti-cancer drug bleomycin.

Bleomycin (BLM) is used as an anti-cancer drug clinically. However, some cancer cells are resistant to BLM, which limits the usage of BLM in chemotherapy. But the underlying mechanism of such resistance is poorly understood. Here we show that the ATP binding cassette (ABC) transporter ABCC3 is required for the BLM-resistance in Arabidopsis. In a genetic screen for ddrm (DNA damage response mutants), we found that loss of ABCC3 confers the hypersensitivity to BLM. In contrast, overexpression of ABCC3 enhances the resistance to BLM. We further found that the expression of ABCC3 is induced by BLM, which is dependent on the protein kinase ATM and the transcription factor SOG1, two master regulators of DNA damage response. Our study revealed that the ABC transporter contributes to BLM-resistance, indicating that the combination of ABC transporter inhibitors and BLM may enhance the efficacy of BLM in cancer therapy.

ABCC3 and GSTM5 gene polymorphisms affect overall survival in Polish acute myeloid leukaemia patients.

Acute myeloid leukaemia (AML) is a very heterogeneous malignancy in which standard treatment is based on chemotherapy. Resistance to chemotherapeutic agents remains a big problem in AML, because negatively influences patient overall survival. Several resistance mechanisms have been described, the best of which is the process of drug removal from the cell and/or nucleus by membrane transport proteins. The aim of the study was to investigate the effect of polymorphism of genes coding ABCC3, GSTM5 involved in the transport and metabolism of drugs. For this purpose 95 newly diagnosed AML patients and 125 healthy controls were genotyped. We showed that ABCC3 rs4148405 and GSTM5 rs3754446, but not ABCC33 rs4793665, affected overall survival in Polish AML patients.

The Role of TRIP6, ABCC3 and CPS1 Expression in Resistance of Ovarian Cancer to Taxanes.

The main problem precluding successful therapy with conventional taxanes is de novo or acquired resistance to taxanes. Therefore, novel experimental taxane derivatives (Stony Brook taxanes; SB-Ts) are synthesized and tested as potential drugs against resistant solid tumors. Recently, we reported alterations in ABCC3, CPS1, and TRIP6 gene expression in a breast cancer cell line resistant to paclitaxel. The present study aimed to investigate gene expression changes of these three candidate molecules in the highly resistant ovarian carcinoma cells in vitro and corresponding in vivo models treated with paclitaxel and new experimental Stony Brook taxanes of the third generation (SB-T-121605 and SB-T-121606). We also addressed their prognostic meaning in ovarian carcinoma patients treated with taxanes. We estimated and observed changes in mRNA and protein profiles of ABCC3, CPS1, and TRIP6 in resistant and sensitive ovarian cancer cells and after the treatment of resistant ovarian cancer models with paclitaxel and Stony Brook taxanes in vitro and in vivo. Combining Stony Brook taxanes with paclitaxel caused downregulation of CPS1 in the paclitaxel-resistant mouse xenograft tumor model in vivo. Moreover, CPS1 overexpression seems to play a role of a prognostic biomarker of epithelial ovarian carcinoma patients' poor survival. ABCC3 was overexpressed in EOC tumors, but after the treatment with taxanes, its up-regulation disappeared. Based on our results, we can suggest ABCC3 and CPS1 for further investigations as potential therapeutic targets in human cancers.

Independent and Synergistic Effects of Knocking out Two ABC Transporter Genes on Resistance to Bacillus thuringiensis Toxins Cry1Ac and Cry1Fa in Diamondback Moth.

Insecticidal proteins from Bacillus thuringiensis (Bt) are used widely in sprays and transgenic crops to control insect pests. However, evolution of resistance by pests can reduce the efficacy of Bt toxins. Here we analyzed resistance to Bt toxins Cry1Ac and Cry1Fa in the diamondback moth (Plutella xylostella), one of the world's most destructive pests of vegetable crops. We used CRISPR/Cas9 gene editing to create strains with knockouts of the ATP-binding cassette (ABC) transporter genes PxABCC2, PxABCC3, or both. Bioassay results show that knocking out either gene alone caused at most 2.9-fold resistance but knocking out both caused >10,320-fold resistance to Cry1Ac and 380-fold resistance to Cry1Fa. Cry1Ac resistance in the double knockout strain was recessive and genetically linked with the PxABCC2/PxABCC3 loci. The results provide insight into the mechanism of cross-resistance to Cry1Fa in diamondback moth. They also confirm previous work with this pest showing that mutations disrupting both genes cause higher resistance to Cry1Ac than mutations affecting either PxABCC2 or PxABCC3 alone. Together with previous work, the results here highlight the value of using single and multiple gene knockouts to better understand the independent and synergistic effects of putative Bt toxin receptors on resistance to Bt toxins.

Prevalence of ABCC3-1767G/A polymorphism among patients with antiretroviral-associated hepatotoxicity.

BACKGROUND: Plasma concentrations of antiretrovirals (ARVs) regimens have considerably varied in individuals of human immunodeficiency virus (HIV) because of variations in the expression of drug-metabolizing and transporter genes. Transporter genes play an important role in the disposition of drugs. Polymorphism in transporter gene (ABCC3) affects the MRP3 expression and varies the treatment outcome. METHOD: We examined the polymorphism of ABCC3-1767G/A gene in a total of 165 HIV patients (out of 165 HIV patients, 34 were with and 131 were without hepatotoxicity) and 156 healthy individuals using the polymerase chain reaction-restriction fragment length polymorphism method. RESULTS: In univariate analysis, we found a decreased prevalence of ABCC3 1767GA, 1767GA+AA genotypes, and 1767A allele in patients with hepatotoxicity as compared to patients without hepatotoxicity (23.5% vs. 28.2% and 23.5% vs. 30.53%; 11.76% vs. 16.41%), while a higher prevalence of 1767AA genotype was observed in HIV patients in comparison with healthy controls (2.3% vs. 1.3%, odds ratio [OR] = 1.71, 95% confidence interval [CI]: 0.23-15.03, p = .89). The frequency of ABCC3-1767AA genotype was dispersed higher in individuals with early and advanced HIV disease stage in comparison with healthy controls (5.3% vs. 1.3%, OR = 4.73, p = .70; 8.9% vs. 1.3%, OR = 1.89, p = .91). A higher occurrence of ABCC3-1767AA genotype was found in tobacco using HIV patients without hepatotoxicity compared with nonusers (4.7% vs. 1.1%, OR = 4.28, p = .52). The distribution of ABCC3-1767GA genotype was higher in nevirapine receiving HIV patients irrespective of their hepatotoxicity status as compared to nonusers (30.4% vs. 9.1%, OR = 3.34, p = .22; 29.4% vs. 16.7%, OR = 1.69, p = .77). In multivariate analysis, HIV patients receiving nevirapine and with hepatotoxicity was found to have a significant risk for severity of hepatotoxicity (OR = 4.56, 95% CI: 1.60-12.99, p = .004). CONCLUSION: ABCC3 1767G/A polymorphism was not significantly associated with susceptibility to ARV-associated hepatotoxicity, although ABCC3 1767AA genotype designated a risk for acquisition of hepatotoxicity and advancement of the disease. Nevirapine usage emerged as an independent risk factor for hepatotoxicity severity.

Bioinformatics Analysis of the Expression of ATP Binding Cassette Subfamily C Member 3 (ABCC3) in Human Glioma.

OBJECTIVE: To investigate the expression of the ABCC3 gene in human glioma and its correlation with the patient's prognosis. METHODS: The cancer genome atlas (TCGA) database was used to analyze the differential expression of the ABCC3 gene in human glioma. The STRING database was used to construct the protein-protein interaction (PPI) network of the ABCC3 gene coding protein. The co-expression genes relevant to the ABCC3 gene were analyzed by the Pearson correlation test. A log-rank test was used to analyze the difference of overall survival (OS) and disease-free survival (DFS) between the high and low ABCC3 gene expression groups. RESULTS: The expression level of the ABCC3 gene in glioma tissues was lower than that of corresponding normal brain tissues. The PPI network contains 51 nodes with the average node degree of 13.3 and the local clustering coefficient of 0.72 which indicated that the PPI enrichment was significant (p<0.001). Ten hub genes (ABCC3,NR1I2,NR1H4,-CYP7A1,SLC10A1,CYP3A4,UGT1A1,UGT1A8,UGT1A6 and ALB) were identified by the cytoscape software. The KEGG analysis was enriched in drug metabolism - cytochrome P450 and PPAR signaling pathway. CFI gene expression level was positive correlated with the ABCC3 expression level (r=0.71, p<0.05). And the CNRIP1 gene expressed was negative correlated with ABCC3 expression (r=-0.43, p<0.05). The overall survival (HR=2.8, P<0.05) and disease-free survival rates (HR=2.0, P<0.05) of patients with ABCC3 low expression glioma were significantly higher than those of patients with high expression of ABCC3. Conclusion The expression level of the ABCC3 gene in glioma was decreased compared to normal brain tissue. The overall survival and disease-free survival of in the ABCC3 low-expression group was significant decreased.

Role of ATP-Binding Cassette Transporter Proteins in CNS Tumors: Resistance- Based Perspectives and Clinical Updates.

Despite gigantic advances in medical research and development, chemotherapeutic resistance remains a major challenge in complete remission of CNS tumors. The failure of complete eradication of CNS tumors has been correlated with the existence of several factors including overexpression of transporter proteins. To date, 49 ABC-transporter proteins (ABC-TPs) have been reported in humans, and the evidence of their strong association with chemotherapeutics' influx, dissemination, and efflux in CNS tumors, is growing. Research studies on CNS tumors are implicating ABC-TPs as diagnostic, prognostic and therapeutic biomarkers that may be utilised in preclinical and clinical studies. With the current advancements in cell biology, molecular analysis of genomic and transcriptomic interplay, and protein homology-based drug-transporters interaction, our research approaches are streamlining the roles of ABC-TPs in cancer and multidrug resistance. Potential inhibitors of ABC-TP for better clinical outcomes in CNS tumors have emerged. Elacridar has shown to enhance the chemo-sensitivity of Dasatanib and Imatinib in various glioma models. Tariquidar has improved the effectiveness of Temozolomide's in CNS tumors. Although these inhibitors have been effective in preclinical settings, their clinical outcomes have not been as significant in clinical trials. Thus, to have a better understanding of the molecular evaluations of ABC-TPs, as well as drug-interactions, further research is being pursued in research labs. Our lab aims to better comprehend the biological mechanisms involved in drug resistance and to explore novel strategies to increase the clinical effectiveness of anticancer chemotherapeutics, which will ultimately improve clinical outcomes.

Curcumol enhances the sensitivity of doxorubicin in triple-negative breast cancer via regulating the miR-181b-2-3p-ABCC3 axis.

Chemoresistance is a major cause of recurrence and poor prognosis in triple-negative breast cancer (TNBC) patients. The essential oil of Rhizoma Curcumae has been recently reported to enhance the chemosensitivity of cancer cells. However, few reports have systematically illuminated the mechanism. Curcumol is the major component of the essential oil of Rhizoma Curcumae. Therefore, we wondered whether curcumol combined with chemotherapy could increase the anticancer effects. In the present study, we evaluated the anticancer effects of doxorubicin and curcumol alone or in combination by a series of growth proliferation and apoptosis assays in TNBC cells. Our results showed that curcumol enhanced the sensitivity of MDA-MB-231 cells to doxorubicin in vitro and in vivo. Through miRNA-seq, we found that miR-181b-2-3p was involved in the curcumol-mediated promotion of doxorubicin-sensitivity in both parental and doxorubicin-resistant MDA-MB-231 (MDA-MB-231/ADR) cells. Further study showed that miR-181b-2-3p suppressed ABCC3 expression by targeting its 3'UTR. More importantly, we identified that overexpression of miR-181b-2-3p sensitized MDA-MB-231/ADR cells to doxorubicin by inhibiting the drug efflux transporter ABCC3. Furthermore, we found that NFAT1 could be activated by curcumol. In addition, ChIP assay results revealed that NFAT1 could directly bind to the promoter region of miR-181b-2-3p. Finally, using PDX models, we identified that curcumol could enhance sensitivity to doxorubicin to suppress tumor growth by the miR-181b-2-3p-ABCC3 axis in vivo. Taken together, our study provides novel mechanistic evidence for curcumol-mediated sensitization to doxorubicin in TNBC, and it highlights the potential therapeutic usefulness of curcumol as an adjunct drug in TNBC patients with doxorubicin-resistance.

MicroRNA-448 overexpression inhibits fibroblast proliferation and collagen synthesis and promotes cell apoptosis via targeting ABCC3 through the JNK signaling pathway.

Idiopathic pulmonary fibrosis (IPF) is a condition that results in the progressive deterioration of lung function with poor prognosis. The current study is aimed at exploring how microRNA-448 (miR-448) targeting ABCC3 affects fibroblast proliferation, apoptosis, and collagen synthesis of mice with IPF via the Jun N-terminal kinase (JNK) signaling pathway. Bioinformatics and dual-luciferase polymerase chain reaction were used to predict the relationship of miR-448 and ABCC3. The expression of miR-448 and ABCC3 was detected in IPF tissues. Using IPF mouse models, lung fibroblasts for the experiments were treated with miR-448 mimic, miR-448 inhibitor, si-ABCC3, or SP600125 (inhibitor of JNK) to evaluate the cell proliferation and apoptosis in response to miR-448. Reverse transcription quantitative polymerase chain reaction and western blot analysis were used to identify the expression of miR-448, ABCC3, and the activation of the JNK signaling pathway. ABCC3 was targeted and downregulated by miR-448 based on bioinformatics prediction and dual-luciferase reporter gene assay. Additionally, miR-448 was found to be highly expressed in IPF lung tissues with low expression levels of ABCC3. In response to the treatment of miR-448 mimic or si-ABCC3, lung fibroblasts exhibited decreased cell proliferation and increased apoptotic rates, whereas the miR-448 inhibitor reversed the conditions. Notably, we also found that miR-448 mimic inhibited the JNK signaling pathway. In conclusion, by using miR-448 to target and downregulate ABCC3 to block the JNK signaling pathway in mice with IPF, we found an increase in fibroblast apoptosis, inhibited cell proliferation, and decreased collagen synthesis of fibroblasts.

Suspension State Promotes Drug Resistance of Breast Tumor Cells by Inducing ABCC3 Overexpression.

Mechanical microenvironment plays a critical role in cancer drug resistance and this study supposed that suspension state might be involved in drug resistance of breast tumor cells. The viability of cell was detected by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. Cell cycle and apoptosis were detected by flow cytometry. Gene and protein were tested by RT-qPCR and Western blot, respectively. Drug resistance of MDA-MB-231 cells cultured for 72 h under suspension state was significantly increased. Suspension state was found to induce the overexpression of adenosine triphosphate-binding cassette subfamily C member 3 (ABCC3) in MDA-MB-231 cells. Silencing of ABCC3 significantly decreased drug resistance of suspension MDA-MB-231 cells. Moreover, suspension state was able to increase lamin A/C accumulation in MDA-MB-231 cells and lamin A/C regulated the expression of ABCC3. Moreover, lamin A/C knockdown also decreased drug resistance of suspension MDA-MB-231 cells, but the effect on drug resistance was less than that of ABCC3 knockdown. Suspension state plays a vital role in promoting drug resistance of MDA-MB-231 cells by inducing ABCC3 overexpression, and lamin A/C accumulation is associated with this process.