KLF14/miR-1283/TFAP2C axis inhibits HER2-positive breast cancer progression via declining tumor cell proliferation.

MiR-1283 has been identified as a tumor suppressor in some malignancies. Whereas, the role of miR-1283 in HER2-positive (HER2+) breast cancer, particularly its role in regulating cell proliferation, one of the most significant features of tumor progression, is unclear. The related microRNA screened by the breast cancer sample GSE131599 dataset were detected in HER2+ breast cancer tissues and cell lines. Then, the obtained miR-1283 was overexpressed in SKBR3 and BT-474 cells followed by relevant functional assays concerning cell proliferation and apoptosis. The xenograft mouse model was induced and the effect of miR-1283 on tumor growth and cell proliferation was examined. The target of miR-1283 and the transcription factor regulating miR-1283 were predicted and identified. Finally, the influence of transcription factor KLF14 on cell proliferation and apoptosis was investigated. An integrated analysis confirmed that miR-1283 expression was significantly decreased in HER2+ breast cancer tissues. Also, by q-RT-PCR detection, miR-1283 expression was markedly reduced in HER2+ breast cancer tissues and cell lines. The miR-1283 overexpression prevented the proliferation and enhanced apoptosis of HER2+ breast cancer cells, as well as inhibited tumor growth. Mechanistically, miR-1283 inhibited TFAP2C expression by targeting the 3'-untranslated regions of TFAP2C messenger RNA, and the KLF14 enhanced miR-1283 level via binding to its promoter. The result subsequently confirmed the KLF14/miR-1283 signaling suppressed cell proliferation in HER2+ breast cancer. Our results suggested that the KLF14/miR-1283/TFAP2C axis inhibited HER2+ breast cancer progression, which might provide novel insight into mechanical exploration for this disease.

Circular RNA circ-ERBB2 promotes HER2-positive breast cancer progression and metastasis via sponging miR-136-5p and miR-198.

BACKGROUND: Circular RNAs (circRNAs) are pivotal regulators of various human cancers and circ-ERBB2 is abnormally expressed in breast cancer cells. However, the role and mechanism of circ-ERBB2 in HER2-positive breast cancer are still unknown. METHODS: The circ-ERBB2 expressions in the tumor tissues of HER2-positive breast cancer patients were tested using quantitative real-time PCR. The circ-ERBB2 function was investigated by cell counting kit 8 assay, Transwell, flow cytometry and Western blot. Mechanistically, fluorescence in situ hybridization, RNA immunoprecipitation, RNA pull-down and dual-luciferase reporter gene assays were conducted to confirm the interaction between circ-ERBB2 and miR-136-5p or miR-198 in HER2-positive breast cancer cells. RESULTS: Circ-ERBB2 was elevated in the tumor tissues of HER2-positive breast cancer patients. Functionally, the interference with circ-ERBB2 repressed HER2-positive breast cancer cell proliferation, migration, invasion and accelerated cell apoptosis. Furthermore, the mechanistic analysis corroborated that circ-ERBB2 acted as a competing endogenous RNA for miR-136-5p or miR-198 to relieve the repressive influence of miR-136-5p or miR-198 on its target transcription factor activator protein 2C (TFAP2C). Meanwhile, in vivo assays further corroborated the oncogenic function of circ-ERBB2 in HER2-positive breast cancer. CONCLUSIONS: Circ-ERBB2 accelerated HER2-positive breast cancer progression through the circ-ERBB2/miR-136-5p/TFAP2C axis or the circ-ERBB2/miR-198/TFAP2C axis.

Hsa_circ_0023990 Promotes Tumor Growth and Glycolysis in Dedifferentiated TC via Targeting miR-485-5p/FOXM1 Axis.

BACKGROUND: During the transformation to dedifferentiated thyroid cancer (TC) types, the ability of papillary thyroid carcinomas (PTCs) to concentrate radioactive iodine might be lost, raising difficulty for the current therapy. circRNAs were proved to be implicated in the progression of various cancers. In this study, we aimed to investigate the functional role and mechanism of hsa_circ_0023990 in dedifferentiated TC. METHODS: The expression pattern of genes were detected using quantitative PCR or western blot assays. Cell proliferation was determined by CCK8, colony formation, EdU, and cell-cycle assays. Glycolysis was assessed using glucose uptake and lactate production assays. Luciferase reporter assay was performed to examine the interactions between miR-485-5p and hsa_circ_0023990 or FOXM1. Xenograft assay was allowed for observation of tumor growth in vivo. RESULTS: Hsa_circ_0023990 and FOXM1 were upregulated in dedifferentiated TC tissues and cell lines. The higher level of hsa_circ_0023900 could stimulate the proliferation and glycolysis of dedifferentiated TC cells via positively regulating FOXM1. Mechanistically, miR-485-5p was demonstrated to interact with hsa_circ_0023990 and FOXM1 and involved in the regulation of has_circ_0023990 and FOXM1 in TC biological processes. CONCLUSION: Our results discovered the functional network of hsa_circ_0023990 in dedifferentiated TC development by facilitating cell proliferation and glycolysis via miR-485-5p/FOXM1 axis, implying that hsa_circ_0023990 might be a potential therapeutic target for the dedifferentiated TC treatment.

Lnc RNA SNHG20 participated in proliferation, invasion, and migration of breast cancer cells via miR-495.

To explore the mechanism of lnc SNHG20 in the regulation of proliferation, invasion, and migration of breast cancer cells. mRNA levels of SNHG20, miR-495, and HER2 were detected by qRT-PCR. Protein level of HER2 was measured by Western blot. Cell proliferation, invasion, and migration were detected by CCK-8 assay, Boyden chamber assay, and Transwell assay. The combination between SNHG20 and miR-495 was confirmed by RNA pull down assay. The combination between miR-495 and HER2 was confirmed by luciferase report assays. We also established breast cancer-bearing mice model and analyzed tumor volumes. Our data showed SNHG20 expression was significantly upregulated, miR-495 expression was significantly downregulated, and HER2 expression was significantly upregulated in breast cancer tissues and cell lines. Besides, SNHG20 promoted the proliferation, invasion, and migration of breast cancer cells. We also found SNHG20 negatively regulated miR-495, and miR-495 could negatively regulate HER2. Moreover, we discovered that SNHG20 regulated HER2 via miR-495. SNHG20 regulated proliferation, invasion, and migration of breast cancer cells via miR-495/HER2. Finally, we confirmed the mechanism of SNHG20 in the regulation of proliferation, invasion, and migration in breast cancer-bearing mice model. SNHG20 regulates HER2 via miR-495 to promote proliferation, invasion, and migration of breast cancer cells.

Preparation and Identification of HER2 Radioactive Ligands and Imaging Study of Breast Cancer-Bearing Nude Mice.

OBJECTIVE: A micro-molecule peptide TP1623 of 99mTc-human epithelial growth factor receptor 2 (HER2) was prepared and the feasibility of using it as a HER2-positive molecular imaging agent for breast cancer was evaluated. METHODS: TP1623 was chemically synthesized and labeled with 99mTc. The labeling ratio and stability were detected. HER2 expression levels of breast cancer cells (SKBR3 and MDA-MB-231) and cell binding activity were measured. Biodistribution of 99mTC-TP1623 in normal mice was detected. SKBR3/MDA-MB-231-bearing nude mice models with high/low expressions of HER2 were established. Tumor tissues were stained with hematoxylin-eosin (HE) and measured by immunohistochemistry to confirm the formation of tumors and HER2 expression. SPECT imaging was conducted for HER2-overexpressing SKBR3-bearing nude mice. The T/NT ratio was calculated and compared with that of MDA-MB-231-bearing nude mice with low HER2 expression. The competitive inhibition image was used to discuss the specific binding of 99mTc- TP1623 and the tumor. RESULTS: The labeling ratio of 99mTc-TP1623, specific activity, and radiochemical purity (RCP) after 6 h at room temperature were (97.39 ± 0.23)%, (24.61 ± 0.06) TBq/mmol, and (93.25 ± 0.06)%, respectively. HER2 of SKBR3 and MDA-MB-231 cells showed high and low expression levels by immunohistochemistry, respectively. The in vitro receptor assays indicated that specific binding of TP1623 and HER2 was retained. Radioactivity in the brain was always at the lowest level, while the clearance rate of blood and the excretion rate of the kidneys were fast. HE staining showed that tumor cells were observed in SKBR3- and MDA-MB-231-bearing nude mice, with significant heteromorphism and increased mitotic count. The imaging of mice showed that targeted images could be made of 99mTc-TP1623 in high HER2-expressing tumors, while no obvious development was shown in tumors in low HER2-expressing nude mice. No development was visible in tumors in competitive inhibition of imaging, which indicates the combination of 99mTc-TP1623 and tumor was mediated by HER2. CONCLUSION: High labeling ratio and specific activity of 99mTc-TP1623 is successfully prepared; it is a molecular imaging agent for HER2-positive tumors that has potential applicative value.

Mutations of C-reactive protein (CRP) -286 SNP, APC and p53 in colorectal cancer: implication for a CRP-Wnt crosstalk.

C-reactive protein (CRP) is an established marker of inflammation with pattern-recognition receptor-like activities. Despite the close association of the serum level of CRP with the risk and prognosis of several types of cancer, it remains elusive whether CRP contributes directly to tumorigenesis or just represents a bystander marker. We have recently identified recurrent mutations at the SNP position -286 (rs3091244) in the promoter of CRP gene in several tumor types, instead suggesting that locally produced CRP is a potential driver of tumorigenesis. However, it is unknown whether the -286 site is the sole SNP position of CRP gene targeted for mutation and whether there is any association between CRP SNP mutations and other frequently mutated genes in tumors. Herein, we have examined the genotypes of three common CRP non-coding SNPs (rs7553007, rs1205, rs3093077) in tumor/normal sample pairs of 5 cancer types (n = 141). No recurrent somatic mutations are found at these SNP positions, indicating that the -286 SNP mutations are preferentially selected during the development of cancer. Further analysis reveals that the -286 SNP mutations of CRP tend to co-occur with mutated APC particularly in rectal cancer (p = 0.04; n = 67). By contrast, mutations of CRP and p53 or K-ras appear to be unrelated. There results thus underscore the functional importance of the -286 mutation of CRP in tumorigenesis and imply an interaction between CRP and Wnt signaling pathway.

[Differentiation of rat bone marrow mesenchymal stem cells into adipocytes and blockage of the differentiation].

OBJECTIVE: To explore the pathogenesis of tumors by blocking the normal differentiation process of stem cells. METHODS: Bone marrow mesenchymal stem cells (BMSCs) from rats were isolated, cultured and purified by whole bone marrow adherence method. The rat BMSCs were induced to differentiate into adipocytes with dexamethasone, insulin and indomethacin. Blockage of the differentiation process was induced by 3-methylcholanthrene (3-MC). RESULTS: The differentiation experiment showed that at 30 days after the induction, oil red O staining-positive cells occurred with increased intracytolasmic lipid droplets, characteristic for adipocytes. The differentiation blockage experiment showed that at 30 days after induction, the deposits of oil red O staining-cytoplasmic lipid droplets was significantly reduced, indicating that the blocked cells were adipocytes, but not fully differentiated. Morphological identification showed that cell contact inhibition disappeared, abnormal cell nuclei, increased number of micronucleus aberration and karyotype abnormalities, indicating that malignant transformation of the stem cells occurred after the differentiation blockage. CONCLUSIONS: The results of this study show a blockage of the differentiation of that stem cells at the intermediate phase, and a tendency of malignant transformation of the stem cells. The results of our study provide new evidence that cancer stem cells may be originated by suppression of stem cell differentiation.

Early recurrence and death after esophagectomy in patients with esophageal squamous cell carcinoma.

BACKGROUND: The aim of this retrospective study is to analyze recurrence and death within 1 year after esophagectomy in patients with esophageal carcinoma. METHODS: The records of 533 consecutive patients with esophageal squamous cell carcinoma who underwent surgery from January 2002 to January 2005 were reviewed. Patients who died of recurrence within 1 year after operation (group A) were compared with patients who survived more than 5 years without any recurrence (group B). Their clinicopathologic characteristics were evaluated by univariate and multivariate analyses. RESULTS: The overall 1-year and 5-year survival rates for the entire cohort were 76.1% and 32.3%, respectively, with the follow-up rate of 93.4%. Of the 119 patients who died within 1 year after the esophagectomy, local recurrence or distant metastasis or both were documented in 62 patients (52.1%). The radicality of resection, size of tumor, radicality of resection, grade of differentiation, depth of invasion, status of lymph node metastasis, number of lymph node metastases, and marginal status were shown by univariate analysis to be the significant prognostic factors. By multivariate analysis, they were also the independent prognostic factors, except for the size of tumor and the radicality of resection. CONCLUSIONS: More than half of early death in esophageal squamous cell carcinoma patients after esophagectomy were still tumor recurrence related, especially hematogeneous spreading. The grade of differentiation, depth of invasion, lymph node metastasis, number of lymph node metastases, and marginal status are valuable prognostic factors in predicting early death.

[Clinical observation on effect of fuzheng yiliu granule on cell cycle and nuclear transcription factor-kappa B in tissue of esophageal-gastric carcinoma].

OBJECTIVE: To observe the effect of Fuzheng Yiliu Granule (FZYLG) on cell cycle and nuclear transcription factor-kappa B (NF-kappa B) in tissue of esophageal-gastric carcinoma. METHODS: Seventy-six patients with esophageal gastric carcinoma were randomly divided into two groups, the FZYLG group and the control group. FZYLG was given to the former for 15 days. The tumor tissue in both groups was resected and cell cycle and apoptosis rate as well as NF-kappa B were determined by flowcytometry. RESULTS: Level of NF-kappa B in the treated group was significantly higher than that in the control group (P < 0.05). In the treated group, the percentage of G0/G1 stage cells were significantly increased and that of S stage significantly decreased (both P < 0.05). At the same time, obvious cell apoptosis was found in the treated group, the apoptosis rate of which was significantly higher than that in the control group (P < 0.01). CONCLUSION: FZYLG can increase the NF-kappa B expression, block the proliferation to promote the apoptosis of tumor cells.