Curcuma zedoaria petroleum ether extract reverses the resistance of triple-negative breast cancer to docetaxel via pregnane X receptor.

BACKGROUND: Triple-negative breast cancer (TNBC) is characterized by its aggressiveness and poor prognosis. Docetaxel is the common chemotherapeutic drug used in the treatment of TNBC. However, resistance to docetaxel has limited the effectiveness of TNBC treatment. Petroleum ether extracts of Curcuma zedoaria (PECZ) can inhibit the proliferation of MDA-MB-231 cells. However, the effect of PECZ on docetaxel resistance is not clear. METHODS: A docetaxel-resistant MDA-MB-231 (MDA-MB-231/docetaxel) cell line was established, and Cell Counting Kit-8 (CCK-8), quantitative real-time PCR (qRT-PCR), and western blotting assays were used to evaluate the effect of docetaxel resistance in MDA-MB-231 cells. Next, CCK-8 was also performed to detect the effect of docetaxel or the combination treatment of docetaxel and PECZ on the proliferation of MDA-MB-231/docetaxel cells. Thereafter, MDA-MB-231/docetaxel cells were subcutaneously injected into nude mice to induce a TNBC xenograft model, and the mice were divided into a model group, docetaxel group, PECZ group, and combination of docetaxel and PECZ group. Subsequently, hematoxylin and eosin (HE) staining, immunohistochemical, qRT-PCR, and western blotting were used to estimate the effect of pre-treatment with PECZ on docetaxel tolerance reversal. RESULTS: PECZ significantly inhibited the expression of pregnane X receptor (PXR), multidrug resistance 1 (MDR1), breast cancer resistance protein (BCRP), and cytochrome P-450 (CYP3A4) in MDA-MB-231/docetaxel cells. Only higher concentrations of docetaxel could inhibit the viability of MDA-MB-231/docetaxel cells. When pre-treated with PECZ, lower concentrations of docetaxel could significantly inhibit cell viability. Meanwhile, combination treatment also reduced the tumor volume, ameliorated the pathological change of tumor tissues, and down-regulated the expressions of PXR, MDR1, BCRP, and CYP3A4 (according to HE staining, immunohistochemical, qRT-PCR and western blotting results in vivo). CONCLUSIONS: Our research showed that PECZ reversed docetaxel resistance in TNBC by PXR both in vitro and in vivo, which provides the basis for further investigations into the potential therapeutic impact of docetaxel resistance in TNBC.

Screening of miRNAs associated with lymph node metastasis in Her-2-positive breast cancer and their relationship with prognosis.

The aim of this study was to identify some biomarkers for predicting lymph node metastasis and prognosis of human epidermal growth factor receptor 2 (Her-2)-positive breast cancer (BC). We analyzed correlations between microRNAs (miRNAs) and the prognosis of patients with BC based on data collected from The Cancer Genome Atlas (TCGA) database. The expression levels of miR-455, miR-143, and miR-99a were measured in clinical samples of Her-2-positive BC patients with different degrees of lymph node metastasis. We investigated the impacts of overexpressed miR-455 on the proliferation and invasiveness of MDA-MB-453 cells and measured its effects on the expression of long non-coding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) by quantitative real-time polymerase chain reaction (qRT-PCR). The expression of miR-455 was significantly and positively correlated to the prognosis and overall survival (OS) of the BC (P=0.028), according to TCGA information. The expression level of miR-455 was positively correlated with OS and relapse-free survival (RFS) of patients with Her-2-positive BC, and was negatively correlated with the number of metastatic lymph nodes (P<0.05). Transwell assay suggested that MDA-MB-453 cells became much less invasive (P<0.01) after being transfected with miR-455 mimics. During the qRT-PCR, the expression level of MALAT1 declined significantly after transfection (P<0.01). Overexpressed miR-455 significantly inhibited the proliferation and migration of MDA-MB-453 cells and the expression of MALAT1. We conclude that miR-455 may be a useful potential biomarker for forecasting lymph node metastasis and the prognosis of Her-2-positive BC patients. miR-455 may play an important role in lymph node metastasis of BC by interacting with MALAT1.

Research Progresses in Cancer Stem Cells of Three Common Fertility-Related Female Malignancies.

With abilities to renew themselves and lead to heterogeneity of tumors, cancer stem cells (CSCs) are similar to stem cells. As three leading causes of death that endanger women's health, breast cancer, ovarian cancer and cervical cancer are characterized by high degree of malignancy, metastasis and recurrence. Associated with women's fertility, these three malignancies are common and representative among females. These years, research findings have suggested that CSCs are closely connected with many cancers (including aforementioned three malignancies) and several processes of tumors such as their genesis and development. CSCs have become great concerns for current cancer treatment and interventions. This paper does not only summarize roles of CSCs in genesis, development, drug resistance, metastasis and recurrence of breast cancer, ovarian cancer and cervical cancer, but also proposes potential methods of treatment and intervention, in hope of inspiring readers and researchers.

Effect of pregnane X receptor expression on drug resistance in breast cancer.

This study was conducted to investigate the effect of increased expression of the nuclear transcription factor receptor pregnane X receptor (PXR) on drug resistance of breast cancer cells. Western blotting was used to detect the expression of PXR in breast carcinoma cells. The PXR agonist SR12813 was used to upregulate the expression of PXR. Semi-quantitative polymerase chain reaction was used to detect PXR gene expression in normal and cancerous breast tissues, as well as the expression levels of the drug-resistant genes multidrug resistance protein 1 (MDR1) and breast cancer resistance protein (BCRP) in breast cancer cells. A Cell Counting Kit-8 assay was used to observe the sensitivity of the breast cancer cells to chemotherapeutic agents. Flow cytometry was used to investigate cell apoptosis. PXR expression was detected in normal and cancerous human breast tissues and in breast cancer cell lines. SR12813 treatment led to an increased expression of PXR protein and an increased expression of drug-resistant genes, MDR1 and BCRP, in MCF-7 and MDA-MB-231 cells. SR12813 pretreatment significantly increased the resistance of MDA-MB-231 cells to docetaxel. A marked increase in resistance to 4-hydroxytamoxifen was also observed in MCF-7 with SR12813 pretreatment. Additionally, we also found that pretreatment with SR12813 led to reduced apoptosis of the two cell strains induced by chemotherapeutic agents. In conclusion, PXR expression has an important effect on the sensitivity to chemotherapy of PXR-positive breast carcinoma. The inhibitory effect of PXR on cell apoptosis may contribute to the drug resistance of breast carcinoma.

Efficacy of combined axitinib with dacarbazine in a B16F1 melanoma xenograft model.

In this study, we evaluated the efficacy and intestinal side effects of the selective inhibitor of vascular endothelial growth factor (VEGF) receptors, axitinib and/or dacarbazine (DTIC), in a B16F1 melanoma xenograft model. C57BL/6 mice were subcutaneously inoculated with B16F1 melanoma cells. The study was randomized into four groups receiving either 0.5% carboxyl methylcellulose, DTIC, axitinib or a combination of DTIC and axitinib. When the experimental period was complete, the tumor tissues from each mouse were excised, photographed and weighed. The tumor and intestinal tissues were harvested with 4% paraformaldehyde, and paraffin-embedded sections were prepared for hematoxylin and eosin staining, immunohistochemical staining (with antibody specific to proliferating cell nuclear antibody) and terminal deoxynucleotidyl-transferase-mediated dUTP nick end labeling assays. The expression of the VEGF and matrix metalloproteinase 9 genes was analyzed using real-time polymerase chain reaction. No significant benefit to treatment with a combination of axitinib and DTIC, as opposed to axitinib alone, was observed; however, the combined treatment did not enhance the level of enteritis compared with that observed in the axitinb group. In addition, axitinib, as a single agent, demonstrated an improved treatment efficacy compared with DTIC. Therefore, axitinib represents a potential novel, efficient and safe anticancer agent, suggesting a possible use for this schedule in treating melanomas that are less sensitive to DTIC.

miR-342 is associated with estrogen receptor-α expression and response to tamoxifen in breast cancer.

Estrogen receptor-α (ERα) is essential for estrogen-dependent growth and its level of expression is a crucial determinant of response to endocrine therapy and prognosis in ERα-positive breast cancer. Breast cancer patients show a wide range of ERα expression levels which change in individual patients during disease progression and in response to systemic therapies. However, little is known concerning how the expression of ERα is regulated in human breast cancer. Recently, several microRNAs (miRNAs) have been identified to regulate ERα expression and to predict ER, progesterone receptor (PR) and human epidermal growth factor 2 (HER2) status. The expression levels of miR-342 and ERα mRNA were analyzed in human breast cancer samples and cell lines by quantitative reverse transcription (RT)-PCR analysis. The correlations between the expression levels of miR-342 and clinicopathological factors were analyzed. Statistically significant associations were observed between miR-342 and ER, HER2 and vascular endothelial growth factor (VEGF) status in the human breast cancer samples and the levels of miR-342 gradually increased as ERα mRNA expression increased. Moreover, ectopic overexpression of miR-342 upregulated the expression levels of the ERα mRNA and significantly sensitized the MCF-7 cells to tamoxifen-induced apoptosis and inhibition of cellular proliferation. These results suggested that miR-342 expression is positively correlated with ERα mRNA expression in human breast cancer and that it may be a significant marker for predicting tamoxifen sensitivity in ERα-positive breast cancer and a potential target for restoring ERα expression and responding to antiestrogen therapy.

Joint detection of multiple immunohistochemical indices and clinical significance in breast cancer.

Breast cancer is one of the most common malignancies in women. This study was conducted to analyze the association between the expressions of eight immunohistochemical (IHC) indices and clinicopathological characteristics in breast cancers (BCs) and investigate the clinical significance. IHC Envision ldpe-g-nvp was used to detect the expression of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor-2 (HER2), vascular endothelial growth factor (VEGF), epidermal growth factor receptor (EGFR), p53, type II topoisomerase (TOPO II) and Ki-67 in postoperative paraffin blocks of 286 cases of invasive BC and statistically analyzed their correlations with clinicopathological characteristics. The positive rates of ER, PR, HER2, VEGF, p53, EGFR, TOPO II and Ki-67 expression were 62.24, 41.96, 57.34, 53.85, 81.82, 46.85, 54.55 and 69.93%, respectively. ER expression was negatively correlated with age, tumor size and histological grade (P<0.05) and PR expression was negatively correlated with age and histological grade (P<0.05). Among the ER, PR and c-erbB-2 statuses, a significant correlation was observed between ER expression and PR status (P=0.0000), whereas the expression of ER and PR exhibited a negative correlation with HER2 status (P<0.05). We also demonstrated a significant correlation between EGFR expression and lymph node metastasis (P=0.0240), p53 expression and tumor size (P=0.0300), p53 and Ki-67 expression and histological grade (P<0.05) and the expressions of VEGF, EGFR, p53, TOPO II, Ki-67 and HER2 status (P<0.05). In addition, the Luminal B and HER2/neu subtypes exhibited a close correlation with age (P<0.01), while the HER2/neu and triple-negative subtypes were positively correlated with poor histological grade (P<0.05). In conclusion, there is a definite correlation between IHC indices and clinicopathological characteristics in BCs. Combined detection of these indices may be significant in the evaluation of biological behavior and prognosis of BC and thus in the diagnosis and comprehensive treatment of this disease.