The long noncoding RNA (lncRNA) LUCAT1 was recently reported to be upregulated and to play an essential role in multiple cancer types, especially colorectal cancer (CRC), but the molecular mechanisms of LUCAT1 in CRC are mostly unreported. Here, a systematic analysis of LUACT1 expression is performed with data from TCGA database and clinic CRC samples. LUCAT1 is identified as a putative oncogene, which is significantly upregulated in CRC and is associated with poor prognosis. Loss of LUCAT1 restricts CRC proliferative capacities in vitro and in vivo. Mechanically, NCL is identified as the protein binding partner of LUCAT1 by using chromatin isolation by RNA purification coupled with mass spectrometry (ChIRP-MS) and RNA immunoprecipitation assays. We also show that NCL directly binds to LUCAT1 via its putative G-quadruplex-forming regions from nucleotides 717 to 746. The interaction between LUCAT1 and NCL interferes NCL-mediated inhibition of MYC and promote the expression of MYC. Cells lacking LUCAT1 show a decreased MYC expression, and NCL knockdown rescue LUCAT1 depletion-induced inhibition of CRC cell proliferation and MYC expression. Our results suggest that LUCAT1 plays a critical role in CRC cell proliferation by inhibiting the function of NCL via its G-quadruplex structure and may serve as a new prognostic biomarker and effective therapeutic target for CRC.

Background: Breast cancer has become one of the most common malignant tumors in women owing to its increasing incidence each year. Clinical studies have shown that Cinnamomum cassia (L.) J. Presl (cinnamon) has a positive influence on the prevention and treatment of breast cancer.Aim: We aimed to screen the potential targets of cinnamon in the treatment of breast cancer through network pharmacology and explore its potential therapeutic mechanism through cell experiments.Methods: We used the TCMSP, TCM Database @ Taiwan, and TCMID websites and established the active ingredient and target database of cinnamon. Thereafter, we used the GeneCards and OMIM databases to establish a breast cancer-related target database, which matched the cinnamon target database. Based on the matching results, the STRING database was used to analyze the interaction between the targets, and the biological information annotation database was used to analyze the biological process of the target (gene ontology) and the pathway enrichment of Kyoto Encyclopedia of Genes and Genomes (KEGG). After establishing the layout of the analysis, we used Cytoscape 3.6.0 software for network analysis. Finally, the cell experiment was used to verify the anti-breast cancer effect of cinnamaldehyde.Results: Our research showed that the main components of cinnamon, including cinnamaldehyde, can play a role in the treatment of breast cancer through 59 possible important targets. Subsequently, enrichment analysis by gene ontology and Kyoto Encyclopedia of Genes and Genomes showed that 83 cell biological processes and 37 pathways were associated with breast cancer (p < 0.05), including the peroxisome proliferator-activated receptor and PI3K-Akt pathway, which are closely related to tumor cell apoptosis. In vitro cell verification experiments showed that cinnamaldehyde can significantly inhibit cell proliferation, change cell morphology, inhibit cell migration and invasion ability, and promote cell apoptosis.Conclusion: Our results showed that cinnamaldehyde is a potential novel drug for the treatment and prevention of breast cancer.

Novel therapeutic strategies for breast cancer are urgently needed due to the sustained development of drug resistance and tumor recurrence. Trivalent arsenic derivative (arsenite, As III) has been reported to induce cytotoxicity in breast cancer cells. We recently demonstrated that As III plus tetrandrine (Tetra), a Chinese plant-derived alkaloid, exerted potent antitumor activity against human breast cancer cells, however, the underlying mechanisms for their action have not been well defined. In order to provide fundamental insights for understanding the action of As III plus Tetra, the effects of the combined regimen on two breast cancer cell lines T47D and MDA-MB-231 were evaluated. Compared to T47D cells, MDA-MB-231 cells were much more susceptible to the synergistic cytotoxic effects of As III and Tetra. Besides the induction of apoptotic/ necrotic cell death, S-phase arrest and autophagic cell death were also observed in MDA-MB-231 cells. Exposure of MDA-MB-231 cells to As III and Tetra caused the activation of MAPKs. Cytotoxicity of the combined regimen in MDA-MB-231 cell was significantly abrogated by SP600125, a potent c-Jun N-terminal kinase (JNK) inhibitor. However, similar abrogation was not caused by p38 and ERK inhibitors. The addition of either autophagy inhibitors (3-methyladenine or wortmannin) or SP600125 corrected the combined regimen-triggered S-phase arrest, whereas had little effect on the apoptosis/ necrosis induction in the cells. Surprisingly, SP600125NC, a negative control for SP600125, significantly strengthened S-phase arrest and the cytotoxicity induced by

Objective. To systematically evaluate the effect and safety of compound Kushen injection (CKI) as an add-on treatment on the treatment for breast cancer. Methods. We searched eight major electronic databases from their inception to November 1, 2021, for randomized clinical trials (RCTs) comparing CKI plus chemotherapy with chemotherapy alone. Primary outcomes included objective response rate (ORR) and disease control rate (DCR), health-related quality of life (HRQoL), progression-free survival (PFS), and overall survival (OS). Secondary outcomes included adverse drug reactions (ADRs) and tumor marker level. We used Cochrane’s RevMan 5.3 for data analysis. The GRADEpro was used to appraise the certainty of evidence. Trial sequential analysis (TSA) was applied to estimate the required sample size in a meta-analysis and test the robustness of the current results. Results. Thirty RCTs with 2556 participants were totally included. CKI plus chemotherapy showed significant effects in increasing ORR (RR 1.30, 95%CI [1.18, 1.43], I2 = 27%, n = 1694), increasing DCR (RR 1.21, 95%CI [1.15, 1.28], I2 = 16%, n = 1627), increasing HRQol as measured by Karnofsky Performance Scale (KPS) score improvement rate (RR 1.42, 95% CI [1.26, 1.61], I2 = 37%, n = 1172), increasing the PFS (MD 2.24 months, 95%CI [1.26, 3.22], n = 94) and the OS (MD 2.24 months, 95%CI [1.45, 3.43], n = 94), compared to chemotherapy alone. The results showed that CKI plus chemotherapy had a lower risk of ADRs than that of chemotherapy alone group. The certainty of evidence of the included trials was generally low to very low. TSA for ORR and KPS score improvement rate demonstrated that the current results reached a sufficient power regarding both numbers of trials and participants. Conclusions. Low certainty of evidence suggested that the combination of CKI and conventional chemotherapy appeared to improve ORR, DCR, and KPS score in breast cancer patients. Conclusions about PFS and OS could not be drawn due to lack of evidence. Additionally, CKI appeared to relieve the risk of ADRs in patients with breast cancer receiving chemotherapies. However, due to weak evidence, the findings should be further confirmed in large and rigorous trials.