Potential clinical significance of ALDH3B1 in auxiliary diagnosis of gastric cancer.

Objective: This research aimed to explore a diagnostic method based on serum ALDH3B1 and to evaluate the clinical diagnostic efficacy in gastric cancer (GC) by comparing it with the traditional GC diagnostic method, the carcinoembryonic protein (CEA) assay. Methods: Serum samples were collected from 70 healthy volunteers and various patients (GC: 76, benign gastric lesions: 20, postoperative: 37, recurrence: 56). The diagnostic efficacy of serum ALDH3B1, CEA and the co-diagnosis were evaluated by receiver operating characteristic curve. ALDH3B1 protein levels were evaluated by western blot. Results: The co-diagnosis of ALDH3B1 and CEA had the highest diagnostic efficacy (area under the curve = 0.841). Conclusion: Serum ALDH3B1 may be used as an auxiliary diagnostic biomarker for GC, and its co-diagnosis with CEA can improve diagnostic efficacy.

ALDH3B1 protects interfollicular epidermal cells against lipid peroxidation via the NRF2 pathway.

Reactive oxygen species (ROS) production is critical for the initiation of wound repair; however, persistently high levels of ROS can lead to lipid peroxidation in cells and thus affect wound healing. Iron is a transition metal that is an essential component of almost all living cells and organisms. When present in excess in cells and tissues, iron disrupts redox homeostasis and catalyzes the generation of ROS, leading to increased lipid peroxidation. In this study, we found that after treating interfollicular epidermal (IFE) cells with different concentrations of holotransferrin (0 µg/ml, 1 µg/ml, 10 µg/ml, 100 µg/ml, and 1 mg/ml), the intracellular iron content increased, and cell viability and function did not differ significantly among the treatment groups of cells. In addition, the level of lipid peroxidation in IFE cells did not increase following holotransferrin treatment. We speculated that there is a protective mechanism within IFE cells that reduces the occurrence of intracellular lipid peroxidation. We also found that the elevated intracellular iron content of IFE cells was accompanied by elevated ALDH3B1 expression. We investigated the effect of ALDH3B1 on the level of lipid peroxidation in IFE cells and found that elevated ALDH3B1 expression decreased the damage to IFE cells induced by lipid peroxidation. In addition, the NRF2 pathway was found to affect the expression of ALDH3B1, which in turn affected lipid peroxidation in IFE cells. These findings suggest that in IFE cells, activation of the NRF2 pathway can increase the expression of ALDH3B1 and thus reduce the production of intracellular ROS and the occurrence of intracellular lipid peroxidation. Therefore, ALDH3B1 may be a potential target for the treatment of chronic wounds.

ALDH3B1 Is an Independent Prognostic Biomarker of Lung Adenocarcinoma.

BACKGROUND: Lung cancer is the leading cause of cancer-related death, and adenocarcinoma is the most common type of lung cancer. Although emerging evidence implicates the role of several aldehyde dehydrogenases in cancer progression, the expression and clinical significance of aldehyde dehydrogenase 3B1 in lung adenocarcinoma has never been studied. MATERIALS: In our study, the expression of aldehyde dehydrogenase 3B1 in 250 cases of lung adenocarcinoma was detected with immunohistochemistry, and the patients were further divided into subgroups with different aldehyde dehydrogenase 3B1 expression. Using real-time polymerase chain reaction, we investigated the aldehyde dehydrogenase 3B1 messenger RNA in 20 lung adenocarcinoma and paired normal lung tissues. With the χ2 test, we evaluated the clinical significance of aldehyde dehydrogenase 3B1 by analyzing its correlation with the clinicopathological factors. Propensity score matching was performed to balance the baseline of cohort. With univariate and multivariate analyses, we screened the prognostic factors of lung adenocarcinoma and identified the independent prognostic factors before and after the propensity score matching. RESULTS: Aldehyde dehydrogenase 3B1 expression was significantly associated with the sex and age of patients, tumor size, and histological grade. High expression of aldehyde dehydrogenase 3B1 predicted the poor prognosis (P = .003). Moreover, male patients (P = .020), large tumor size (P = .009), advanced T stage (P = .001), positive lymphatic invasion (P < .001), and advanced tumor-node-metastasis stage (P < .001) were all the prognostic factors for unfavorable outcome. Aldehyde dehydrogenase 3B1 was an independent prognostic biomarker of lung adenocarcinoma, indicating the poor prognosis. In addition, after balancing the baseline characteristics by propensity score matching, we also demonstrated that aldehyde dehydrogenase 3B1 was an independent prognostic biomarker of lung adenocarcinoma (P = .007). CONCLUSIONS: Aldehyde dehydrogenase 3B1 was an independent prognostic biomarker of lung adenocarcinoma, indicating the unfavorable prognosis. Postoperative detection of aldehyde dehydrogenase 3B1 would help stratify the high-risk patients with lung adenocarcinoma and guide individual treatment.

Pathways of retinoid synthesis in mouse macrophages and bone marrow cells.

In vivo pathways of natural retinoid metabolism and elimination have not been well characterized in primary myeloid cells, even though retinoids and retinoid receptors have been strongly implicated in regulating myeloid maturation. With the use of a upstream activation sequence-GFP reporter transgene and retrovirally expressed Gal4-retinoic acid receptor α in primary mouse bone marrow cells, we identified 2 distinct enzymatic pathways used by mouse myeloid cells ex vivo to synthesize retinoic acid receptor α ligands from free vitamin A metabolites (retinyl acetate, retinol, and retinal). Bulk Kit(+) bone marrow progenitor cells use diethylaminobenzaldehyde-sensitive enzymes, whereas bone marrow-derived macrophages use diethylaminobenzaldehyde-insensitive enzymes to synthesize natural retinoic acid receptor α-activating retinoids (all-trans retinoic acid). Bone marrow-derived macrophages do not express the diethylaminobenzaldehyde-sensitive enzymes Aldh1a1, Aldh1a2, or Aldh1a3 but instead, express Aldh3b1, which we found is capable of diethylaminobenzaldehyde-insensitive synthesis of all trans-retinoic acid. However, under steady-state and stimulated conditions in vivo, diverse bone marrow cells and peritoneal macrophages showed no evidence of intracellular retinoic acid receptor α-activating retinoids, despite expression of these enzymes and a vitamin A-sufficient diet, suggesting that the enzymatic conversion of retinal is not the rate-limiting step in the synthesis of intracellular retinoic acid receptor α-activating retinoids in myeloid bone marrow cells and that retinoic acid receptor α remains in an unliganded configuration during adult hematopoiesis.