• BMB Reports
• /
• 제52권3호
• /
• pp.214-219
• /
• 2019

The role of tumor-proximal factors in tumor plasticity during chemoresistance and metastasis following chemotherapy is well studied. However, the role of endothelial cell (EC) derived paracrine factors in tumor plasticity, their effect on chemotherapeutic outcome, and the mechanism by which these paracrine factors modulate the tumor microenvironment are not well understood. In this study, we report a novel mechanism by which endothelial miR-125a and let-7e-mediated regulation of interleukin-6 (IL-6) signaling can manipulate vasculogenic mimicry (VM) formation of MDA-MB-231 breast cancer cells. We found that endothelial IL-6 levels were significantly higher in response to cisplatin treatment, whereas levels of IL-6 upon cisplatin exposure remained unchanged in MDA-MB-231 breast cancer cells. We additionally found an inverse correlation between IL-6 and miR-125a/let-7e expression levels in cisplatin treated ECs. Interestingly, IL-6, IL-6 receptor (IL-6R), and signal transducer and activator of transcription 3 (STAT3) genes in the IL-6 pathway are closely regulated by miR-125a and let-7e, which directly target its 3' untranslated region. Functional analyses revealed that endothelial miR-125a and let-7e inhibit IL-6-induced adhesion of monocytes to ECs. Furthermore, conditioned medium from cisplatin treated ECs induced a significantly higher formation of VM in MDA-MB-231 breast cancer cells as compared to that from intact ECs; this effect of cisplatin treatment was abrogated by concurrent overexpression of miR-125a and let-7e. Overall, this study reveals a novel EC-tumor cell crosstalk mediated by the endothelial miR-125a/let-7e-IL-6 signaling axis, which might improve chemosensitivity and provide potential therapeutic targets for the treatment of cancer.

• 대한의생명과학회지
• /
• 제17권3호
• /
• pp.261-265
• /
• 2011

Parkin is a putative tumor suppressor protein and its expression is frequently reduced or absent in several types of tumors. In this study, we examined the role of Parkin in mRNA expression of monocyte chemotactic protein-1 (MCP-1) in the breast cancer cell line MCF7. Expression of MCP-1 mRNA increased after TNF-${\alpha}$ treatment. However, overexpression of Parkin induced a decrease in expression of MCP-1 mRNA in TNF-${\alpha}$-stimulated MCF7. This decrease in MCP-1 mRNA by Parkin overexpression occurred in a dose- and time-dependent manner. Using a wound scratch assay, we found that Parkin overexpression in MCF7 cells also resulted in a decrease in cell migration. These results suggest that Parkin down-regulates MCP-1 synthesis leading to decreased migration of tumor cells. We suggest that one possible mechanism by which Parkin acts as a tumor suppressor is by inhibiting migration or metastasis of cancer cells.

• IMMUNE NETWORK
• /
• 제21권3호
• /
• pp.21.1-21.22
• /
• 2021

Myeloid-derived suppressor cells (MDSCs) have strong immunosuppressive activity and are morphologically similar to conventional monocytes and granulocytes. The development and classification of these cells have, however, been controversial. The activation network of MDSCs is relatively complex, and their mechanism of action is poorly understood, creating an avenue for further research. In recent years, MDSCs have been found to play an important role in immune regulation and in effectively inhibiting the activity of effector lymphocytes. Under certain conditions, particularly in the case of tissue damage or inflammation, MDSCs play a leading role in the immune response of the central nervous system. In cancer, however, this can lead to tumor immune evasion and the development of related diseases. Under cancerous conditions, tumors often alter bone marrow formation, thus affecting progenitor cell differentiation, and ultimately, MDSC accumulation. MDSCs are important contributors to tumor progression and play a key role in promoting tumor growth and metastasis, and even reduce the efficacy of immunotherapy. Currently, a number of studies have demonstrated that MDSCs play a key regulatory role in many clinical diseases. In light of these studies, this review discusses the origin of MDSCs, the mechanisms underlying their activation, their role in a variety of clinical diseases, and their function in immune response regulation.

• Journal of Acupuncture Research
• /
• 제32권1호
• /
• pp.97-107
• /
• 2015

Objectives : The purpose of this study is to explore the antitumor mechanism and effects of tetrodotoxin through a literature review of experimental and clinical studies. Methods : Medical databases, including The Cochrane Library, Pubmed, NDSL, RISS4u and National Assembly Library, were searched for relevant articles published from January 1, 2000 to October 31, 2014 using the keywords 'tetrodotoxin', 'cancer' and 'tumor'. The results were classified into experimental studies(in vitro and in vivo) and clinical studies. Analysis of the results was conducted on several research areas including the mechanism, antitumor effect and adverse effects of tetrodotoxin(TTX). Results : A total of 34 experimental studies(32 in vitro and 2 in vivo) and 3 clinical studies were found in the search. Most of the experimental studies suggested blocking of voltage-gated sodium channels in metastasis of tumor cells as the main antitumor mechanism of TTX. The most common type of cancers mentioned in the experimental studies were prostate and breast cancer. All of the clinical studies were on the application of TTX on moderate to severe cancer-related pain. No adverse effects of TTX were reported in in vivo studies but mild to moderate adverse events were reported in clinical studies. Conclusions : The results show that tetrodotoxin, which is the main component of Tetraodontidae(commonly known as pufferfish) poison, could be clinically used for antitumor therapy. However, further studies should be conducted on its safety.

• 대한골관절종양학회지
• /
• 제9권2호
• /
• pp.169-177
• /
• 2003

목적: 골육종 환자에서 p21, p27 단백질의 발현과 국소 재발, 원격 전이 및 생존율과의 상관 관계에 대해 알아보고자 하였다. 대상 및 방법: 골육종 환자 40명의 종양학적 결과를 후향적으로 조사하였으며, 이들의 파라핀에 포매된 조직을 실험 재료로 사용하였다. 단백질 발현은 조직 배열법을 이용한 면역염색 화학법으로 측정하였다. 결과: 40례의 골육종에서 p21은 38례에서 발현되었고 p27은 14례에서 발현되었다. p21은 많이 발현될수록 화학요법에 대한 조직의 반응도가 나빴고(p=0.002), 원격 전이가 유의하게 많았다(p=0.024). p27 양성군에서는 음성군에 비해 원격 전이의 발생이 유의하게 적어(p=0.028), p27의 발현이 안될수록 예후가 좋지 않았다. 결론: p21, p27은 서로 상반된 결과를 보였으며, 환자의 예후와 밀접한 관계를 가짐을 알수 있었다. 하지만, 두 인자의 작용 기전은 명확하지 않아 지속적인 연구가 필요할 것으로 사료되었다.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권5호
• /
• pp.2061-2068
• /
• 2015

Background: Tumors are largely unable to metabolize ketone bodies for energy due to various deficiencies in one or both of the key mitochondrial enzymes, which may provide a rationale for therapeutic strategies that inhibit tumor growth by administration of a ketogenic diet with average protein but low in carbohydrates and high in fat. Materials and Methods: Thirty-six male BALB/C nude mice were injected subcutaneously with tumor cells of the colon cancer cell line HCT116. The animals were then randomly split into three feeding groups and fed either a ketogenic diet rich in omega-3 fatty acids and MCT (MKD group; n=12) or lard only (LKD group; n=12) or a standard diet (SD group; n=12) ad libitum. Experiments were ended upon attainment of the target tumor volume of $600mm^3$ to $700mm^3$. The three diets were compared for tumor growth and survival time (interval between tumor cell injection and attainment of target tumor volume). Results: The tumor growth in the MKD and LKD groups was significantly delayed compared to that in the SD group. Conclusions: Application of an unrestricted ketogenic diet delayed tumor growth in a mouse xenograft model. Further studies are needed to address the mechanism of this diet intervention and the impact on other tumor-relevant parameters such as invasion and metastasis.

• Asian Pacific Journal of Cancer Prevention
• /
• 제13권8호
• /
• pp.3751-3755
• /
• 2012

Aim: Tea polyphenols are known to play roles in critical steps of human lung carcinoma cell metastasis. For understanding the mechanisms whereby they inhibit tumor metastasis, the present study was conducted to investigate their effects on the adhesion of highly metastatic lung carcinoma cell lines (PG cells) to endothelial cells (EC cells) and adhesion molecule expression in vitro. Methods: The expression of CD44 or CD54 in the PG cells was detected by flow cytometry and adhesion of PG cells to EC cells was assessed by confocal microscopy double fluorescence staining. Results: The results showed that tea polyphenols: (1) inhibited the expression of CD44 and CD54, two important adhesion molecules in the PG cells in a dose-dependent manner; (2) significantly blocked the adhesion of PG cells to EC cells not only in a state of rest but also when active; and (3) influenced CD44 and CD54 expression during the adhesion process of PG cells to EC cells. Conclusions: The data indicated that the blocking role of tea polyphenols in the adhesion of PG cells to EC cells is related to CD44 and CD54. The mechanism of tea polyphenol prevention of human lung carcinoma metastasis might be through inhibiting adhesion molecule expression to block cancer cell adhesion.

• Molecules and Cells
• /
• 제42권4호
• /
• pp.321-332
• /
• 2019

The brain is the most common metastatic site of lung adenocarcinoma; however, the mechanism of this selective metastasis remains unclear. We aimed to verify the hypothesis that exposure of tumor cells to the brain microenvironment leads to changes in their gene expression, which promotes their oriented transfer to the brain. A549 and H1299 lung adenocarcinoma cells were exposed to human astrocyte-conditioned medium to simulate the brain microenvironment. Microarray analysis was used to identify differentially expressed genes, which were confirmed by quantitative real-time PCR and western blotting. Knockdown experiments using microRNAs and the overexpression of genes by cell transfection were performed in addition to migration and invasion assays. In vitro findings were confirmed in clinical specimens using immunohistochemistry. We found and confirmed a significant increase in insulin-like growth factor binding protein-3 (IGFBP3) levels. Our results also showed that the up-regulation of IGFBP3 promoted A549 cell epithelial-mesenchymal transition, migration, and invasion, while the knockdown of IGFBP3 resulted in decreased cell motility. We also found that Transforming growth factor-${\beta}$ (TGF-${\beta}$)/Mothers against decapentaplegic homolog 4 (Smad4)-induced epithelial-mesenchymal transition was likely IGFBP3-dependent in A549 cells. Finally, expression of IGFBP3 was significantly elevated in pulmonary cancer tissues and intracranial metastatic tissues. Our data indicate that up-regulation of IGFBP3 might mediate brain metastasis in lung adenocarcinoma, which makes it a potential therapeutic target.

• Journal of Microbiology and Biotechnology
• /
• 제31권6호
• /
• pp.775-783
• /
• 2021

Sea cucumber, Holothuria scabra, is a well-known traditional Asian medicine that has been used for suppressing inflammation, promoting wound healing, and improving immunity. Moreover, previous studies demonstrated that the extract from H. scabra contains many bioactive compounds with potent inhibitory effect on tumor cell survival and progression. However, the effect of the methanolic extract from the body wall of H. scabra (BWMT) on human prostate cancer cells has not yet been investigated. In this study, we aimed to investigate the effects and underlying mechanism of BWMT on prostate cancer cell viability and metastasis. BWMT was obtained by maceration with methanol. The effect of BWMT on cell viability was assessed by MTT and colony formation assays. The intracellular ROS accumulation was evaluated using a DCFH-DA fluorescence probe. Hoechst 33342 staining and Annexin V-FITC/PI staining were used to examine the apoptotic-inducing effect of the extract. A transwell migration assay was performed to determine the anti-metastasis effect. BWMT significantly reduced cell viability and triggered cellular apoptosis by accumulating intracellular ROS resulting in the upregulation of JNK and p38 signaling pathways. In addition, BWMT also inhibited the invasion of PC3 cells by downregulating MMP-2/-9 expression via the ERK pathway. Consequently, our study provides BWMT from H. scabra as a putative therapeutic agent that could be applicable against prostate cancer progression.

• 대한두경부종양학회지
• /
• 제20권1호
• /
• pp.13-18
• /
• 2004

Objectives: Cancer lethality is usually the result of local invasion and metastasis of neoplastic cell from the primary tumor. Because of their ability to degrade extracellular matrix components, matrix metalloproteinases (MMPs) and basic fibroblast growth factor (bFGF) have been implicated in the breakdown of basement membrane and underlying stroma, thereby facilitating tumor growth and invasion. It has been well established that MMPs and bFGF expression correlate with cervical lymph node metastasis, but studies on expression in the metastatic cervical lymph node itself are not enough. We have analyzed matrix metalloproteinases (MMPs) and basic fibroblast growth factor (bFGF) in squamous cell carcinoma of the head and neck and metastatic cervical lymph node, and evaluated their relationship and clinicophathologic significance. Material and Methods: 20 cases of squamous cell carcinoma of the head and neck were entered on the study of immunohistochemical stains for MMP-9 and bFGF in the obtained tissue from primary tumor and metastatic cervical lymph node. We analyzed the relationship between MMP-9, bFGF expression of the primary tumor and metastatic node with age, sex, T-stage, N-stage, histologic grade, pathologic stage and disease free survival. Results: Expression of MMP-9 and bFGF in cancer cell and metastatic lymph node was higher than that in normal cell and lymph node. According to histologic differentiation, expression of MMP-9 of the metastatic cervical lymph node was higher than primary tumor. Considering to other clinicopathologic factor, no statistical significance was seen in MMP-9 and bFGF. Conclusion: We found that expression of MMP-9 is higher in the metastatic lymph node than primary tumor in the poorly differentiated squamous cell carcinoma. But we don't find out the statistical significance in relation between bFGF and clinical factors. So we guess that some different mechanism of MMP-9 and bFGF in Head & Neck squamous cell carcinoma exist. Further studies will be necessary to establish their pathogenesis in the Head and Neck cancer.