E2F3/CDCA2 reduces radiosensitivity in gastric adenocarcinoma by activating PI3K/AKT pathway.

OBJECTIVES: Gastric adenocarcinoma is primarily responsible for tumor-associated deaths and its incidence is increasing global. CDCA2 is a nuclear protein binding to protein phosphatase one γ (PP1γ) and plays a pro-oncogenic role in tumors. This study aimed to elucidate the biological function of CDCA2 in gastric adenocarcinoma progression and radiosensitivity, as well as its potential mechanisms. METHODS: Differentially expressed mRNAs in gastric adenocarcinoma were obtained by bioinformatics and upstream regulatory factors were predicted. The correlation between their expressions was analyzed. The expressions of E2F3 and CDCA2 in cells were assayed by qRT-PCR and their regulatory relationship was validated by molecular experiments. Cell viability was tested via CCK-8. Cell proliferation and survival after radiotherapy were determined by colony formation assay. The expressions of PI3K/AKT pathway-related proteins were assessed through western blot. RESULTS: CDCA2 was significantly upregulated in gastric adenocarcinoma tissues and cells, promoted cell proliferation, and reduced radiosensitivity. The impact of CDCA2 on cell proliferation and radiosensitivity was reversed by the PI3K/AKT inhibitor. Furthermore, the upstream transcription factor of CDCA2 was found to be E2F3, which was highly expressed in gastric adenocarcinoma. The binding relationship between the two was validated by dual luciferase and ChIP experiments. The rescue experiment showed that E2F3 activated CDCA2 to drive cell proliferation and reduce radiosensitivity through PI3K/AKT pathway in gastric adenocarcinoma. CONCLUSION: In summary, this study found that E2F3 activated CDCA2 to drive cell proliferation and reduce radiosensitivity in gastric adenocarcinoma through the PI3K/AKT pathway, suggesting that E2F3/CDCA2 axis is a new therapeutic target for gastric adenocarcinoma. ADVANCES IN KNOWLEDGE: 1. CDCA2 reduced the radiosensitivity of gastric adenocarcinoma cells;2. CDCA2 reduced the radiosensitivity of gastric adenocarcinoma cells through the PI3K/AKT pathway;3. E2F3 activated CDCA2 to reduce the radiosensitivity of gastric adenocarcinoma cells through the PI3K/AKT pathway.

SPI1 involvement in malignant melanoma pathogenesis by regulation of HK2 through the AKT1/mTOR pathway.

Spi-1 proto-oncogene (SPI1) plays a vital role in carcinogenesis. Our work aimed to investigate the potential regulatory mechanism of SPI1 in melanoma. The mRNA and protein levels were measured via qRT-PCR and Western blotting. Cell viability was assessed by CCK-8 assay. The target relationship between SPI1 and hexokinase 2 (HK2) was determined using dual-luciferase reporter detection. ChIP was conducted to confirm the targeted relationship between SPI1 and the HK2 promoter. Immunohistochemistry analysis was conducted to measure the positive cell number of SPI1 and HK2 in melanoma tissues. The cell migration abilities were determined using a wound healing assay. Glucose consumption, pyruvate dehydrogenase activity, lactate production and ATP levels were measured to assess glycolysis. SPI1 transcription in melanoma cells and tissues was dramatically higher than that in adjacent normal tissues and epidermal melanocyte HEMa-LP, respectively. Knockdown of SPI1 restrained cell viability, metastasis and glycolysis in melanoma cells. SPI1 directly targeted HK2, and knockdown of SPI1 repressed HK2 expression. Overexpression of HK2 weakened the inhibitory effects of SPI1 knockdown on the viability, metastasis and glycolysis of melanoma cells. The serine-threonine kinase 1 (AKT1)/mammalian target of rapamycin (mTOR) axis is involved in melanoma progression. SPI1 knockdown restrained melanoma cell proliferation, metastasis and glycolysis by regulating the AKT1/mTOR pathway.

CREB1 regulates KPNA2 by inhibiting mir-495-3p transcription to control melanoma progression : The role of the CREB1/miR-495-3p/KPNA2 axis in melanoma progression.

BACKGROUND: Melanoma is a common type of skin cancer, and its incidence is increasing gradually. Exploring melanoma pathogenesis helps to find new treatments. OBJECTIVE: We aimed to explore the potential molecular mechanisms by which CREB1 regulates melanoma. METHODS: TransmiR and ALGGEN were used to predict targets of CREB1 in the promoter of miR-495-3p or miR-495-3p and KPNA2, and a dual-luciferase reporter assay was performed to detect binding of CREB1 to these promoters. In addition, binding of CREB1 to the miR-495-3p promoter was confirmed by a ChIP assay. qRT‒PCR was carried out to detect mRNA levels of miR-495-3p, CREB1 and KPNA2. An EdU assay was conducted to detect cell viability. Transwell assays and flow cytometry were performed to assess cell migration and invasion and apoptosis, respectively. Moreover, factors associated with overall survival were analysed by using the Cox proportional hazards model. RESULTS: Our results show miR-495-3p to be significantly decreased in melanoma. Additionally, miR-495-3p overexpression inhibited melanoma cell viability. CREB1 targeted miR-495-3p, and CREB1 overexpression enhanced melanoma cell viability by inhibiting miR-495-3p transcription. Moreover, miR-495-3p targeted KPNA2, and CREB1 regulated KPNA2 by inhibiting miR-495-3p transcription to enhance melanoma cell viability. CONCLUSION: CREB1 regulates KPNA2 by inhibiting miR-495-3p transcription to control melanoma progression. Our results indicate the molecular mechanism by which the CREB1/miR-495-3p/KPNA2 axis regulates melanoma progression.

Choroidal thickness in Chinese patients with non-arteritic anterior ischemic optic neuropathy.

BACKGROUND: Non-arteritic anterior ischemic optic neuropathy (NA-AION) is one of the most common types of ischemic optic neuropathy. Several recent studies suggested that abnormalities of choroidal thickness might be associated with NA-AION. The main objective of this case-control study was to evaluate whether choroidal thickness is an ocular risk factor for the development of NA-AION by evaluating the peripapillary and subfoveal choroidal thicknesses in affected Chinese patients. METHODS: Forty-four Chinese patients with unilateral NA-AION were recruited and compared with 60 eyes of 60 normal age and refractive-error matched control subjects. Peripapillary and subfoveal choroidal thicknesses were measured by enhanced depth imaging optical coherence tomography. Choroidal thicknesses of eyes with NA-AION and unaffected fellow eyes were compared with normal controls. Choroidal thicknesses of NA-AION eyes with or without optic disc edema were also compared. The correlation between choroidal thickness and retinal nerve fiber layer (RNFL) thickness, logMAR best-corrected visual acuity (BCVA), and the mean deviation (MD) of Humphrey static perimetry in NA-AION eyes were analyzed. RESULTS: The peripapillary choroidal thicknesses at the nasal, nasal inferior and temporal inferior segments in NA-AION eyes with optic disc edema were significantly thicker compared with that of normal subjects (P < 0.05). There was no significant difference in the choroidal thicknesses between the unaffected fellow eyes of NA-AION patients and normal eyes of healthy controls; or between the NA-AION eyes with resolved optic disc edema and normal eyes (all P > 0.05). No significant correlation between choroidal thickness and RNFL thickness, logMAR BCVA and perimetry MD was found in eyes affected by NA-AION (all P > 0.05). CONCLUSIONS: Increase in peripapillary choroid thickness in some segments was found in NA-ION eyes with optic disc edema. However, our findings do not support the hypothesis that choroidal thickness is abnormal in Chinese patients with NA-AION compared with normal subjects with similar age and refractive error status.