Estrogen inhibits colonic smooth muscle contractions by regulating BKß1 signaling.

The estrogen inhibits colonic smooth muscle contractions, which may lead to constipation. However, the mechanisms of inhibition are poorly understood. Therefore, the present study examined the effect of estrogen on rat colonic smooth muscle contractions and its potential association with the large-conductance Ca2+-activated K+ channels ß1 (BKß1) subunit. Twenty-four female Sprague Dawley rats were randomly assigned to 4 groups. After 2 weeks of intervention, the contraction activity of isolated colonic smooth muscle and the expression of BKß1 in colonic smooth muscle of rats were detected. Additionally, in order to investigate the effects of estrogen on BKß1 expression and calcium mobilization, in vitro experiments were conducted using rat and human colonic smooth muscle cells (SMCs). BKß1 shRNA was used to investigate whether calcium mobilization is affected by BKß1 in colonic SMCs. To explore the relationship between ERß and BKß1, serial deletions, site-directed mutagenesis, a dual-luciferase reporter assay, and chromatin immunoprecipitation assays were employed. In response to E2, colonic smooth muscle strips showed a decrease in tension, while IBTX exposure transiently increased tension. Furthermore, in these muscle tissues, BKß1 and α-SMA were found to be co-expressed. The E2 group showed significantly higher BKß1 expression. In cultured colonic SMCs, the expression of BKß1 was found to increase in the presence of E2 or DPN. E2 treatment reduced Ca2+ concentrations, while BKß1 shRNA treatment increased Ca2+ concentrations relative to the control. ERß-initiated BKß1 expression appears to occur via binding to the BKß1 promoter. These results indicated that E2 may upregulate BKß1 expression via ERß and inhibit colonic smooth muscle contraction through ERß by directly targeting BKß1.

Copper in cancer: from limiting nutrient to therapeutic target.

As an essential nutrient, copper's redox properties are both beneficial and toxic to cells. Therefore, leveraging the characteristics of copper-dependent diseases or using copper toxicity to treat copper-sensitive diseases may offer new strategies for specific disease treatments. In particular, copper concentration is typically higher in cancer cells, making copper a critical limiting nutrient for cancer cell growth and proliferation. Hence, intervening in copper metabolism specific to cancer cells may become a potential tumor treatment strategy, directly impacting tumor growth and metastasis. In this review, we discuss the metabolism of copper in the body and summarize research progress on the role of copper in promoting tumor cell growth or inducing programmed cell death in tumor cells. Additionally, we elucidate the role of copper-related drugs in cancer treatment, intending to provide new perspectives for cancer treatment.

miR-22 Suppresses EMT by Mediating Metabolic Reprogramming in Colorectal Cancer through Targeting MYC-Associated Factor X.

Colorectal cancer (CRC) is one of the most frequent gastrointestinal cancers. MicroRNAs (miRNAs) have been proved to be unusually expressed in CRC progression and thus alter multiple pathological processes in CRC cells. However, the specific roles and mechanisms of miR-22 in CRC have not been clearly reported. MicroRNA-22 (miR-22) and MYC-associated factor X (MAX) expressions were determined by RT-qPCR in CRC tissues and cells. The targeted regulatory effects of miR-22 and MAX were confirmed by luciferase reporter and coimmunoprecipitation assays. Also, gain- and loss-of-function and rescue experiments were used to elucidate the function and mechanism of miR-22 and MAX in CRC cells and the mouse xenograft model. We discovered that miR-22 was hypermethylated and downregulated, while MAX was upregulated in CRC. miR-22 markedly inhibited migration, invasion, glycolysis, and cancer stem cell transcription factors in CRC cells. In addition, it was found that miR-22 can directly target MAX. Additional functional experiments confirmed that MAX overexpression can rescue the effects of miR-22 on the behavior of CRC cells. This study suggested that miR-22, as a cancer suppressor, participates in CRC progression by targeting MAX, which might provide basic information for therapeutic targets for CRC.

Zinc finger protein 384 enhances colorectal cancer metastasis by upregulating MMP2.

Zinc finger proteins (ZNFs) serve key roles in tumor formation and progression; however, the functions and underlying mechanisms of dysregulated ZNF384 in colorectal cancer (CRC) are yet to be fully elucidated. Therefore, the present study initially aimed to investigate the expression levels of ZNF384 in CRC samples. Moreover, lentiviral ZNF384 overexpression and ZNF384 knockdown models were established in CRC cells. Transwell, wound healing and in vivo tail vein metastasis assays were carried out to evaluate the effects of ZNF384 on CRC cell metastasis. Furthermore, reverse transcription­quantitative PCR, western blotting, serial deletion, site­directed mutagenesis, dual­luciferase reporter and chromatin immunoprecipitation assays were conducted to investigate the potential underlying mechanisms. The results of the present study demonstrated that ZNF384 expression was markedly increased in CRC samples and this was associated with a poor prognosis. Notably, ZNF384 overexpression increased the levels of CRC cell invasion and migration, whereas ZNF384 knockdown inhibited CRC development. Moreover, the results of the present study demonstrated that ZNF384 mediated the expression of MMP2. MMP2 knockdown inhibited ZNF384­mediated CRC cell invasion and migration, whereas MMP2 overexpression ameliorated ZNF384 knockdown­induced inhibition of CRC progression. In addition, the results of the present study demonstrated that hypoxia­inducible factor 1α (HIF­1α) had the ability to bind to the ZNF384 promoter, thereby initiating ZNF384 expression. In human­derived CRC samples, the expression levels of ZNF384 were positively correlated with both MMP2 and HIF­1α expression. Collectively, these findings highlighted that ZNF384 may act as a prognostic marker and regulator of CRC metastasis.

MicroRNA-23b-3p targets non-SMC condensing I complex subunit G to promote proliferation and inhibit apoptosis of colorectal cancer cells via regulation of the PI3K/AKT signaling pathway.

Colorectal cancer (CRC) is one of the most common types of malignancy worldwide and has a poor prognosis. Non-SMC condensing I complex subunit G (NCAPG) has been reported to be upregulated in numerous types of malignant tumor. However, to the best of our knowledge, its clinicopathological and biological significance in CRC remain to be elucidated. The results of the present study revealed that NCAPG expression levels were upregulated in human CRC tissues and cell lines. The upregulated expression of NCAPG was positively associated with patient clinicopathological characteristics, such as differentiation and tumor size, and independently associated with poor survival. Consistent with the clinical observations, NCAPG was discovered to promote the proliferation and inhibit the apoptosis of CRC cells. Moreover, NCAPG-knockdown inhibited CRC cell proliferation by regulating the PI3K/AKT signaling pathway. Furthermore, NCAPG was identified as a potential target of microRNA (miR)-23b-3p, which was subsequently demonstrated to negatively regulate NCAPG expression. In conclusion, the findings of the current study indicated that the miR-23b-3p/NCAPG/PI3K/AKT signaling axis may play an important role in CRC carcinogenesis, and the status of the molecule may represent a promising prognostic marker for the disease.

Glutamate receptor, ionotropic, N­methyl D­aspartate­associated protein 1 promotes colorectal cancer cell proliferation and metastasis, and is negatively regulated by miR­296­3p.

N­methyl D­aspartate receptors (NMDARs) are closely associated with the development, growth and metastasis of cancer. Glutamate receptor, ionotropic, N­methyl D­aspartate­associated protein 1 (GRINA) is a member of the of the NMDAR family, and its aberrant expression is associated with gastric cancer. However, the role of GRINA in colorectal cancer (CRC) is not completely understood. In the present study, expression profiles of GRINA in several CRC databases were obtained and further verified using clinical CRC samples. The effects of GRINA overexpression on CRC progression both in vivo and in vitro were assessed. Briefly, cell proliferation was detected using MTT assay, and cell migration and invasion ability were evaluated by wound healing and Transwell assay. In addition, the molecular mechanism underlying the upregulated expression of GRINA in CRC was investigated. The regulatory association between GRINA and miR­296­3p was detected by luciferase assay, reverse transcription­quantitative PCR and western blotting. The results demonstrated that GRINA expression levels were significantly increased in tumor samples compared with those in healthy samples, and upregulated expression of GRINA was associated with a less favorable prognostic outcome in patients with CRC. GRINA overexpression significantly increased CRC cell proliferation, invasion and migration. Additionally, it was determined that GRINA was post­transcriptionally regulated by microRNA (miR)­296­3p. Together, the results of the present study suggested the potential importance of the miR­296­3p/GRINA axis and highlighted potential novel targets for the management of CRC.

Cytochrome C Oxidase Assembly Factor 1 Homolog Predicts Poor Prognosis and Promotes Cell Proliferation in Colorectal Cancer by Regulating PI3K/AKT Signaling.

PURPOSE: Colorectal cancer (CRC) is one of the most common malignancies in the world. The prognosis of advanced CRC is still poor. The purpose of this study was to identify a gene expression profile associated with CRC that may contribute to the early diagnosis of CRC and improve patient prognosis. PATIENTS AND METHODS: Five pairs of CRC tissues and paracancerous tissues were used to identify causative genes using microarray assays. The prognostic value of Cytochrome C Oxidase Assembly Factor 1 Homolog (COA1) in CRC was assessed in 90 CRC patients. Loss-of-function assays, cell proliferation assays using Celigo and MTT, colony formation assays, a subcutaneous xenograft mouse model, and apoptosis assays were used to define the effects of downregulation of COA1 in CRC cells in vitro and in vivo. The underlying molecular mechanisms of COA1 in CRC were also investigated. RESULTS: The causative gene COA1 was identified through microarray analysis. COA1 expression in CRC was notably associated with pathologic differentiation, tumor size, and tumor depth. COA1 expression may act as an independent prognostic factor for overall survival of CRC. Knockdown of COA1 inhibited the proliferation of CRC cells in vitro and the tumorigenicity of CRC cells in vivo. Decreased COA1 expression induced apoptosis of CRC cells. Based on the microarray assay results comparing HCT116 cells transfected with lentivirus encoding anti-COA1 shRNA or negative control shRNA, ingenuity pathway analysis (IPA) revealed that the PI3K/AKT signaling pathway was significantly enriched. Moreover, CCND1, mTOR, AKT1, and MDM2 were identified as the downstream genes of COA1. CONCLUSION: These findings demonstrate that COA1 promotes CRC cell proliferation and inhibits apoptosis by regulating the PI3K/AKT signaling pathway. Our results implicate COA1 as a potential oncogene involved in tumor growth and progression of CRC.