The expression levels of CYP3A4 and CYP3A5 serve as potential prognostic biomarkers in lung adenocarcinoma

Potential Association of Cytochrome P450 Copy Number Alteration in Tumour with Chemotherapy Resistance in Lung Adenocarcinoma Patients

Resistance to anticancer agents is a major obstacle to efficacious tumour therapy and responsible for high cancer-related mortality rates. Some resistance mechanisms are associated with pharmacokinetic variability in anticancer drug exposure due to genetic polymorphisms of drug-metabolizing cytochrome P450 (CYP) enzymes, whereas variations in tumoural metabolism as a consequence of CYP copy number alterations are assumed to contribute to the selection of resistant cells. A high-throughput quantitative polymerase chain reaction (qPCR)-based method was developed for detection of CYP copy number alterations in tumours, and a scoring system improved the identification of inappropriate reference genes that underwent deletion/multiplication in tumours. The copy numbers of both the target (CYP2C8, CYP3A4) and the reference genes (ALB, B2M, BCKDHA, F5, CD36, MPO, TBP, RPPH1) established in primary lung adenocarcinoma by the qPCR-based method were congruent with those determined by next-generation sequencing (for 10 genes, slope = 0.9498, r2 = 0.72). In treatment naïve adenocarcinoma samples, the copy number multiplication of paclitaxel-metabolizing CYP2C8 and/or CYP3A4 was more prevalent in non-responder patients with progressive disease/exit than in responders with complete remission. The high-throughput qPCR-based method can become an alternative approach to next-generation sequencing in routine clinical practice, and identification of altered CYP copy numbers may provide a promising biomarker for therapy-resistant tumours.

MiR-30a-3p Suppresses the Growth and Development of Lung Adenocarcinoma Cells Through Modulating GOLM1/JAK-STAT Signaling

A considerable amount of people succumbs to lung adenocarcinoma (LUAD) due to its high incidence and mortality. This study attempted to reveal the impacts of GOLM1 on LUAD. This work analyzed GOLM1 expression in LUAD and normal tissue and studied its prognostic value utilizing data from The Cancer Genome Atlas. RNA and protein levels were, respectively, determined utilizing qRT-PCR and western blot. Cell-aggressive behaviors were assessed employing Cell Counting Kit-8, scratch healing, and Transwell assays. The targetting relationship between GOLM1 and miR-30a-3p was assayed by dual-luciferase method. GOLM1 up-regulation in LUAD was found in TCGA and it was also a negative factor for survival in patients. GOLM1 overexpression promoted cell progression in LUAD. Down-regulated miR-30a-3p in LUAD was an upstream regulatory miRNA of GOLM1 in terms of molecular mechanism. Further, rescue assays illustrated that miR-30a-3p overexpression attenuated the GOLM1 facilitating impacts on LUAD progression. Finally, we proved that miR-30a-3p/GOLM1 regulated progression of LUAD cells via JAK-STAT pathway. Collectively, the inhibitory impacts of miR-30a-3p on LUAD growth may be mediated by GOLM1/JAK-STAT, which may contribute to the diagnosis of LUAD therapy and the development of therapeutic tools.

Expression of Cytochrome P450 Enzymes in Pediatric Non-Rhabdomyosarcoma Soft Tissue Sarcomas: Possible Role in Carcinogenesis and Treatment Response

The 5-year relative survival rate estimate of treated patients with non-rhabdomyosarcoma soft tissue sarcomas (NRSTS) is ∼50% since they generally present with tumor progression, relapse, metastasis, and/or chemoresistance. The expression of cytochrome P450 (CYP) enzymes in malignancies can affect the pharmacology of drugs commonly used in chemotherapy or confer susceptibility to development of chemical carcinogenesis; in addition, their specific tumor expression can be used as a therapeutic target. Using qPCR and Western blot assays, the expression of CYP1B1, CYP2E1, CYP3A4, and CYP3A5 were analyzed in a cohort of tumor tissue paired with non-malignant adjacent tissue of patients with NRSTS. The mRNA and protein expression of CYP1B1, CYP2E1, and CYP3A4 were significantly increased in tumor tissue. We propose that the expression of these isoforms is related to carcinogenesis and chemoresistance frequently observed in these neoplasms.

Variation in Expression of Cytochrome P450 3A Isoforms and Toxicological Effects: Endo- and Exogenous Substances as Regulatory Factors and Substrates

The CYP3A subfamily, which includes isoforms CYP3A4, CYP3A5, and CYP3A7 in humans, plays important roles in the metabolism of various endogenous and exogenous substances. Gene and protein expression of CYP3A4, CYP3A5, and CYP3A7 show large inter-individual differences, which are caused by many endogenous and exogenous factors. Inter-individual differences can cause negative outcomes, such as adverse drug events and disease development. Therefore, it is important to understand the variations in CYP3A expression caused by endo- and exogenous factors, as well as the variation in the metabolism and kinetics of endo- and exogenous substrates. In this review, we summarize the factors regulating CYP3A expression, such as bile acids, hormones, microRNA, inflammatory cytokines, drugs, environmental chemicals, and dietary factors. In addition, variations in CYP3A expression under pathological conditions, such as coronavirus disease 2019 and liver diseases, are described as examples of the physiological effects of endogenous factors. We also summarize endogenous and exogenous substrates metabolized by CYP3A isoforms, such as cholesterol, bile acids, hormones, arachidonic acid, vitamin D, and drugs. The relationship between the changes in the kinetics of these substrates and the toxicological effects in our bodies are discussed. The usefulness of these substrates and metabolites as endogenous biomarkers for CYP3A activity is also discussed. Notably, we focused on discrimination between CYP3A4, CYP3A5, and CYP3A7 to understand inter-individual differences in CYP3A expression and function.

Carboxypeptidase E mRNA: Overexpression predicts recurrence and death in lung adenocarcinoma cancer patients

BACKGROUND

Effective biomarkers for prediction of recurrence of lung adenocarcinoma cancer (LADC) patients are needed to determine treatment strategies post-surgery to improve outcome.

OBJECTIVE

This study evaluates the efficacy of carboxypeptidase E (CPE) mRNA including its splice isoforms, CPE-ΔN, as a biomarker for predicting recurrence in adenocarcinoma patients.

METHODS

RNA was extracted from resected tumors from 86 patients with different stages of non-small cell LADC. cDNA was synthesized and qRT-PCR carried out to determine the copy numbers of CPE/CPE-ΔN mRNA. Patients were followed for 7 years post-tumor resection to determine recurrence and death.

RESULTS

ROC curve analysis showed the overall AUC for CPE/CPE-ΔN copy number was 0.563 in predicting recurrence and 0.563 in predicting death. Kaplan-Meier survival analysis showed statistical difference (p= 0.018), indicating that patients with high CPE/CPE-ΔN copy numbers had a shorter time of disease-free survival and also shorter time to death (p= 0.035). Subgroup analyses showed that association of disease-free survival time with CPE/CPE-ΔN copy number was stronger among stage I and II LADC patients (p= 0.047).

CONCLUSIONS

CPE/CPE-ΔN mRNA is a potentially useful biomarker for predicting recurrence and death in LADC patients, especially in identifying patients at high risk of recurrence at early stages I and II.

CYP3A4 genetic variants are associated with susceptibility of non-small cell lung cancer in a Shaanxi Han population

PURPOSE

Lung cancer (LC) is one of the fastest-growing malignant tumors in the world in terms of morbidity and mortality. CYP3A4 plays a crucial role in the occurrence of LC. Little is known about the contribution of CYP3A4 polymorphisms for non-small cell lung cancer (NSCLC) risk. This study aimed to explore the correlation of CYP3A4 genetic variants (rs3735451, rs4646440, rs35564277, and rs4646437) with NSCLC risk.

METHODS

Four single nucleotide polymorphisms (SNPs) were genotyped by Agena MassARRAY in this case-control study (507 NSCLC patients and 505 controls) among a Shaanxi Han population. Hardy-Weinberg equilibrium (HWE) of each SNP in controls was evaluated by exact test. The association of CYP3A4 polymorphisms with NSCLC risk was explored by calculating odds ratios (OR) and 95% confidence intervals (CI) using logistic regression analysis with adjustment for age and gender.

RESULTS

Our research revealed that rs4646440 was significantly associated with an increased risk of NSCLC (OR 2.64, p = .005), while rs4646437 played a protective role in NSCLC risk (OR 0.48, p = 4.00 × 10^-7). Stratified analyses indicated that rs4646440 significantly enhanced the susceptibility of NSCLC in BMI > 24 kg/m², non-smokers and non-drinkers (OR 14.29, p = .012; OR 1.56, p = .023; OR 1.67, p = .031, respectively). Besides, we observed that rs3735451 exhibited an increased risk of NSCLC in BMI > 24 kg/m² (OR 2.47, p = .030), whereas rs4646437 had a reduced risk of NSCLC in BMI ≤ 24 kg/m² (OR 0.47, p = 5.17 × 10^-5). We also found that rs35564277 was considered as a protective factor of NSCLC in non-smokers (OR 0.50, p = .032).

CONCLUSION

Our study indicated that CYP3A4 genetic variants were associated with NSCLC susceptibility in a Shaanxi Han population.

Cytochrome P450 3A4, 3A5, and 2C8 expression in breast, prostate, lung, endometrial, and ovarian tumors: relevance for resistance to taxanes

Enzymes of the cytochrome P450 (CYP) subfamily 3A and 2C play a major role in the metabolism of taxane anticancer agents. While their function in hepatic metabolism of taxanes is well established, expression of these enzymes in solid tumors may play a role in the in situ metabolism of drugs as well, potentially affecting the intrinsic taxane susceptibility of these tumors. This article reviews the available literature on intratumoral expression of docetaxel- and paclitaxel-metabolizing enzymes in mammary, prostate, lung, endometrial, and ovarian tumors. Furthermore, the clinical implications of the intratumoral expression of these enzymes are reviewed and the potential of concomitant treatment with protease inhibitors (PIs) as a method to inhibit CYP3A4-mediated metabolism is discussed.

Hypoxia increases chemoresistance in human medulloblastoma DAOY cells via hypoxia‑inducible factor 1α‑mediated downregulation of the CYP2B6, CYP3A4 and CYP3A5 enzymes and inhibition of cell proliferation

Medulloblastomas are among the most frequently diagnosed pediatric solid tumors, and drug resistance remains as the principal cause of treatment failure. Hypoxia and the subsequent activation of hypoxia-inducible factor 1α (HIF-1α) are considered key factors in modulating drug antitumor effectiveness, but the underlying mechanisms in medulloblastomas have not yet been clearly understood. The aim of the present study was to determine whether hypoxia induces resistance to cyclophosphamide (CPA) and ifosfamide (IFA) in DAOY medulloblastoma cells, whether the mechanism is dependent on HIF-1α, and whether involves the modulation of the expression of cytochromes P450 (CYP)2B6, 3A4 and 3A5 and the control of cell proliferation. Monolayer cultures of DAOY medulloblastoma cells were exposed for 24 h to moderate (1% O₂) or severe (0.1% O₂) hypoxia, and protein expression was evaluated by immunoblotting. Cytotoxicity was studied with the MTT assay and by Annexin V/PI staining and flow cytometry. Cell proliferation was determined by the trypan-blue exclusion assay and cell cycle by propidium iodide staining and flow cytometry. Hypoxia decreased CPA and IFA cytotoxicity in medulloblastoma cells, which correlated with a reduction in the protein levels of CYP2B6, CYP3A4 and CYP3A5 and inhibition of cell proliferation. These responses were dependent on hypoxia-induced HIF-1α activation, as evidenced by chemical inhibition of its transcriptional activity with 2-methoxyestradiol (2-ME), which enhanced the cytotoxic activity of CPA and IFA and increased apoptosis. Our results indicate that by stimulating HIF-1α activity, hypoxia downregulates the expression of CYP2B6, CYP3A4 and CYP3A5, that in turn leads to decreased conversion of CPA and IFA into their active forms and thus to diminished cytotoxicity. These results support that the combination of HIF-1α inhibitors and canonical antineoplastic agents provides a potential therapeutic alternative against medulloblastoma.

Knockdown of LINC01614 inhibits lung adenocarcinoma cell progression by up-regulating miR-217 and down-regulating FOXP1

We tried to identify the function of LINC01614 in lung adenocarcinoma (LUAD) and reveal its underlying mechanisms. qRT‐PCR was applied to assess the expression of LINC016014 in LUAD tissues, noncancerous tissues and cells. Through colony formation assay, MTT assay and apoptosis analysis, we examined the variation of cell proliferation and apoptosis ability after silencing LINC01614. Moreover, the targeting interactions among LINC01614, miR‐217 and FOXP1 were validated via luciferase reporter assay, and then, we regulated the expression of miR‐217 and FOXP1 to ascertain their importance in cell proliferation and apoptosis. LINC01614 and FOXP1 were found to be up‐regulated in LUAD tumours and cells, whereas miR‐217 was down‐regulated. The experiment showed that target‐specific selectivity exists between LINC01614‐miR‐217 and miR‐217‐FOXP1 3′UTR. Furthermore, we disclosed that inhibition of LINC01614 could activate miR‐217, which subsequently restrained FOXP1. It was proved that LINC01614 promoted FOXP1 by inhibiting miR‐217, which ultimately stimulated the development of LUAD.

Microarray analyses reveal genes related to progression and prognosis of esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma is a high morbidity and mortality cancer in China. Here are few biomarkers and therapeutic targets. Our study was aimed to identify candidate genes correlated to ESCC. Oncomine, The Cancer Genome Atlas, Gene Expression Omnibus were retrieved for eligible ESCC data. Deregulated genes were identified by meta-analysis and validated by an independent dataset. Survival analyses and bioinformatics analyses were used to explore potential mechanisms. Copy number variant analyses identified upstream mechanisms of candidate genes. In our study, top 200 up/down-regulated genes were identified across two microarrays. A total of 139 different expression genes were validated in GSE53625. Survival analysis found that nine genes were closely related to prognosis. Furthermore, Gene Ontology analyses and Kyoto Encyclopedia of Genes and Genomes analyses showed that different expression genes were mainly enriched in cell division, cell cycle and cell-cell adhesion pathways. Copy number variant analyses indicated that overexpression of ECT2 and other five genes were correlated with copy number amplification. The current study demonstrated that ECT2 and other eight candidate genes were correlated to progression and prognosis of esophageal squamous cell carcinoma, which might provide novel insights to the mechanisms.