Gonadotropin-releasing hormone agonists for ovarian protection during breast cancer chemotherapy: a systematic review and meta-analysis.

IMPORTANCE: The increasing trend of delaying childbirth means that more women are being diagnosed with breast cancer before having given birth to their desired number of children. Although chemotherapy can significantly improve the prognosis of this population, it also causes ovarian damage, including premature ovarian insufficiency and infertility. Gonadotropin-releasing hormone agonists (GnRHa) have shown promising fertility protective activity in premenopausal women, but their clinical usage remains controversial. OBJECTIVE: Here, we conducted a meta-analysis to assess the efficacy of GnRHa when administered concurrently with chemotherapy that included cyclophosphamide in the prevention of chemotherapy-induced ovarian damage in premenopausal women. EVIDENCE REVIEW: An extensive literature search was performed using the PubMed, Embase, and Cochrane databases. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were determined. FINDINGS: Eleven randomized controlled trials with a total of 1,219 participants were included in the analyses. A significantly higher number of women treated with GnRHa experienced the resumption of ovarian function after chemotherapy than those who did not receive this treatment (OR, 3.04; 95% CI, 1.87-4.94; P < 0.001). Regarding spontaneous pregnancy, a statistically significant difference was observed only in hormone receptor-negative participants (OR, 2.06; 95% CI, 1.03-4.11; P = 0.04). CONCLUSIONS AND RELEVANCE: When treating premenopausal women with breast cancer, the administration of GnRHa concurrently with chemotherapy appeared to improve the resumption rate of ovarian function; however, the spontaneous pregnancy rate only improved in hormone receptor-negative patients. Thus, the use of GnRHa during chemotherapy may represent a feasible strategy for preserving ovarian function in women with breast cancer.

Preparation, Biocompatibility and Antitumor Activity of Nanodelivery System Targeting Breast Cancer Base on a Silica Nanoparticle.

BACKGROUND: Breast cancer (BC) is the most common type of cancer among women worldwide, and about 30% of males will have recurrent disease. METHODS: In order to treat recurrent BC, we designed a type of silica nanodelivery system loaded with epirubicin and curcumin (composite nanoparticles, CNPs). To promote CNPs clinical application, the stability, the blood, immune and cell compatibility, skin stimulation experiments, anti-tumor activity in vivo and in vitro were studied. RESULTS: In our study, the CNPs had a particle size of 73.9 nm and a uniform size and morphology; moreover, they maintained physical and chemical stability in the blood protein environment. Additionally, results showed that nanoparticles had good blood and immune compatibility, and they did not affect intracellular superoxide dismutase (SOD) and intracellular catalase (CAT). Skin stimulation experiments showed that CNPs did not cause any obvious irritative damage to the intact skin of rabbits. In the cytotoxicity study, CNPs showed strongest antitumor activity. The results of cell cycle and apoptosis studies showed that CNPs could mainly induce apoptosis of S and G2/M phase cells. In vivo, CNPs showed strongest aggregation in the tumor after 6 h of tail vein administration, and a large amount of CNPs continued to accumulate in the blood after 12 h of administration, indicating that CNPs had long circulation ability. The in vivo antitumor activities showed that CNPs had the strongest antitumor activity and tumor targeting ability, and hematoxylin-eosin staining of internal organs showed no obvious difference between treatment groups and negative control. CONCLUSION: CNPs have an ideal biosafety and therapeutic effect for recurrent BC, and they have potential clinical application value.

Platinum-based neoadjuvant chemotherapy for triple-negative breast cancer: a systematic review and meta-analysis.

BACKGROUND: Triple-negative breast cancer (TNBC) is associated with higher aggressiveness and mortality than hormone-positive breast cancer because of the lack of approved therapeutic targets. Patients with TNBC who attain a pathological complete response (pCR) after neoadjuvant chemotherapy have improved survival. Platinum-based agents show promising activity in TNBC; however, their use remains controversial. We conducted a meta-analysis to assess the role of platinum-based agents in neoadjuvant chemotherapy in patients with TNBC. METHODS: We performed an extensive literature search of the Pubmed, Embase, and Cochrane databases. We calculated pooled odds ratios (OR) with 95% confidence intervals (CI) for the identified studies. RESULTS: Eight randomized controlled trials with 1345 patients were included in the analysis. The addition of platinum-based agents improved pCR compared with neoadjuvant therapy based on anthracyclines, cyclophosphamide, taxanes, and fluorouracil (49.1% vs. 35.9%; OR: 1.87, 95% CI: 1.23-2.86). Hematological adverse events were similar in both groups, except for more thrombocytopenia in the platinum-based group (OR: 7.96, 95% CI: 3.18-19.93). CONCLUSION: The addition of platinum-based agents to neoadjuvant chemotherapy improved pCR rates in patients with TNBC, with a slight increase in hematological toxicities. Platinum-based agents might thus be an accessible and economically viable option in patients with TNBC.

Knockdown of circDENND4C inhibits glycolysis, migration and invasion by up-regulating miR-200b/c in breast cancer under hypoxia.

BACKGROUND: Hypoxia is a key feature of breast cancer, which affects cancer development, metastasis and metabolism. Previous studies suggested that circular RNAs (circRNAs) could participate in cancer progression and hypoxia regulation. This study aimed to investigate the role of circRNA differentially expressed in normal cells and neoplasia domain containing 4C (circDENND4C) in breast cancer progression under hypoxia. METHODS: Forty-three patients with breast cancer were involved in this study. Breast cancer cell lines MDA-MB-453 and SK-BR-3 were cultured under hypoxia (1% O2) for experiments in vitro. The expression levels of circDENND4C, microRNA-200b (miR-200b) and miR-200c were measured by quantitative real-time polymerase chain reaction. Glycolysis was investigated by glucose consumption, lactate production and hexokinase II (HK2) protein level. Migration and invasion were evaluated via trans-well assay and protein levels of matrix metallopeptidase 9 (MMP9) and MMP2. The interaction between circDENND4C and miR-200b or miR-200c was explored by bioinformatics analysis, luciferase assay and RNA immunoprecipitation. Murine xenograft model was established to investigate the anti-cancer role of circDENND4C in vivo. RESULTS: circDENND4C highly expressed in breast cancer was up-regulated in response to hypoxia. Knockdown of circDENND4C decreased glycolysis, migration and invasion in breast cancer cells under hypoxia. circDENND4C was validated as a sponge of miR-200b and miR-200c. Deficiency of miR-200b or miR-200c reversed the suppressive effect of circDENND4C knockdown on breast cancer progression. Moreover, silence of circDENND4C reduced xenograft tumor growth by increasing miR-200b and miR-200c. CONCLUSION: circDENND4C silence suppresses glycolysis, migration and invasion in breast cancer cells under hypoxia by increasing miR-200b and miR-200c.

TGF-ß1-induced chondrogenesis of bone marrow mesenchymal stem cells is promoted by low-intensity pulsed ultrasound through the integrin-mTOR signaling pathway.

BACKGROUND: Low-intensity pulsed ultrasound (LIPUS) is a mechanical stimulus that plays a key role in regulating the differentiation of bone marrow mesenchymal stem cells (BMSCs). However, the way in which it affects the chondrogenic differentiation of BMSCs remains unknown. In this study, we aimed to investigate whether LIPUS is able to influence TGF-ß1-induced chondrogenesis of BMSCs through the integrin-mechanistic target of the Rapamycin (mTOR) signaling pathway. METHODS: BMSCs were isolated from rat bone marrow and cultured in either standard or TGF-ß1-treated culture medium. BMSCs were then subjected to LIPUS at a frequency of 3 MHz and a duty cycle of 20%, and integrin and mTOR inhibitors added in order to analyze their influence on cell differentiation. BMSCs were phenotypically analyzed by flow cytometry and the degree of chondrogenesis evaluated through toluidine blue staining, immunofluorescence, and immunocytochemistry. Furthermore, expression of COL2, aggrecan, SOX9, and COL1 was assessed by qRT-PCR and western blot analysis. RESULTS: We found that LIPUS promoted TGF-ß1-induced chondrogenesis of BMSCs, represented by increased expression of COL2, aggrecan and SOX9 genes, and decreased expression of COL1. Notably, these effects were prevented following addition of integrin and mTOR inhibitors. CONCLUSIONS: Taken together, these results indicate that mechanical stimulation combined with LIPUS promotes TGF-ß1-induced chondrogenesis of BMSCs through the integrin-mTOR signaling pathway.

Low-Intensity Pulsed Ultrasound Treatment at an Early Osteoarthritis Stage Protects Rabbit Cartilage From Damage via the Integrin/Focal Adhesion Kinase/Mitogen-Activated Protein Kinase Signaling Pathway.

OBJECTIVES: To investigate whether low-intensity pulsed ultrasound (US) has different protective effects on early and late rabbit osteoarthritis cartilage via the integrin/focal adhesion kinase (FAK)/mitogen-activated protein kinase (MAPK) signaling pathway. METHODS: Thirty-six New Zealand White rabbits were divided into early control, early osteoarthritis, early treatment, late control, late osteoarthritis, and late treatment groups. The early and late osteoarthritis and treatment groups underwent anterior cruciate ligament transection. The remaining groups underwent sham operations with knee joint exposure. The early and late treatment groups were exposed to low-intensity pulsed US 4 and 8 weeks after surgery. After 6 weeks of US exposure, pathologic changes on the articular surface of the femoral condyle were assessed by modified Mankin scores. Expression of type II collagen, matrix metalloproteinase, integrin ß1, phosphorylated FAK, and MAPKs (including extracellular signal-regulated kinase 1/2, MAPK 38, and c-Jun N-terminal kinase) was assessed by Western blot analysis. RESULTS: Cartilage damage was less severe in the early treatment group than the early osteoarthritis group. The Mankin score was significantly lower in the early treatment group than the early osteoarthritis group (P < .05). There was no significant difference in cartilage damage or Mankin score between the late treatment and late osteoarthritis groups. There was a significant increase in type II collagen expression but a significant decrease in matrix metalloproteinase 13 expression in the early treatment group compared to the early osteoarthritis group, whereas no significant difference was found between the late treatment and late osteoarthritis groups. Integrin ß1 and phosphorylated FAK expression was significantly higher, and phosphorylated extracellular signal-regulated kinase 1/2 and phosphorylated MAPK 38 expression was significantly lower in the early treatment group than the early osteoarthritis group. CONCLUSIONS: Our findings indicate that low-intensity pulsed US protects cartilage from damage in early-stage osteoarthritis via the integrin/FAK/MAPK pathway.

Low-Intensity Pulsed Ultrasound Affects Chondrocyte Extracellular Matrix Production via an Integrin-Mediated p38 MAPK Signaling Pathway.

Although low-intensity pulsed ultrasound (LIPUS) regulates p38 mitogen-activated protein kinase (MAPK) and promotes cartilage repair in osteoarthritis, the role of integrin-mediated p38 MAPK in the effect of LIPUS on extracellular matrix (ECM) production of normal and OA chondrocytes remains unknown. The aim of this study was to investigate whether LIPUS affects ECM production in normal and OA rabbit chondrocytes through an integrin-p38 signaling pathway. A rabbit model of OA was established by anterior cruciate ligament transection, and chondrocytes were isolated from normal or OA cartilage and cultured in vitro. Chondrocytes were treated with LIPUS and then pre-incubated with the integrin inhibitor GRGDSP or the p38 inhibitor SB203580. Expression of type II collagen, MMP-13, integrin ß1, p38 and phosphorylated p38 was assessed by Western blot analysis. We found that type II collagen and integrin ß1 were upregulated (p < 0.05), whereas MMP-13 was downregulated (p < 0.05) in normal and OA chondrocytes. Furthermore, phosphorylated p38 was upregulated (p < 0.05) in normal chondrocytes, but downregulated (p < 0.05) in OA chondrocytes after LIPUS stimulation. Pre-incubation of chondrocytes with the integrin inhibitor disrupted the effects of LIPUS on normal and OA chondrocytes. Pre-incubation of chrondocytes with the p38 inhibitor reduced the effects of LIPUS on normal chondrocytes, but had no impact on OA chondrocytes. Our findings suggest that the integrin-p38 MAPK signaling pathway plays an important role in LIPUS-mediated ECM production in chondrocytes.

Effects of low-intensity pulsed ultrasound on integrin-FAK-PI3K/Akt mechanochemical transduction in rabbit osteoarthritis chondrocytes.

The effect of low-intensity pulsed ultrasound (LIPUS) on extracellular matrix (ECM) production via modulation of the integrin/focal adhesion kinase (FAK)/phosphatidylinositol 3-kinase (PI3K)/Akt pathway has been investigated in previous studies in normal chondrocytes, but not in osteoarthritis (OA). Therefore, we investigated the LIPUS-induced integrin ß1/FAK/PI3K/Akt mechanochemical transduction pathway in a single study in rabbit OA chondrocytes. Normal and OA chondrocytes were exposed to LIPUS, and mRNA and protein expression of cartilage, metalloproteinases and integrin-FAK-PI3K/Akt signal pathway-related genes was determined by quantitative reverse transcription polymerase chain reaction and Western blotting, respectively. Compared with levels in normal chondrocytes, expression levels of ECM-related genes were significantly lower in OA chondrocytes and those of metalloproteinase-related genes were significantly higher. In addition, integrin ß1 gene expression and the phosphorylation of FAK, PI3K and Akt were significantly higher in OA chondrocytes. The expression of all tested genes was significantly increased except for that of metalloproteinase, which was significantly decreased in the LIPUS-treated OA group compared to the untreated OA group. LIPUS may affect the integrin-FAK-PI3K/Akt mechanochemical transduction pathway and alter ECM production by OA chondrocytes. Our findings will aid the future development of a treatment or even cure for OA.