Identifying miRNA biomarkers for breast cancer and ovarian cancer: a text mining perspective

Text phrase-mining in identifying and classifying maternal proteins and genes across preeclampsia and similar pathologies

This study aims to demonstrate that text phrase-mining and natural language processing (NLP) can annotate huge quantities of obstetrics textual data for the discovery and evaluation of maternal protein/gene (MPG)-disease interactions involved in the preeclampsia pathway. We employ a phrase-mining/NLP pipeline to evaluate unique MPGs involved in six cardiovascular derangements with overlapping presentations during pregnancy. The diseases were matched with Medical Subject Headings. A textual corpus was developed from abstracts matched to these terms through PubMed. Fourty-four MPGs were identified with respect to the diseases. Processing was performed, with unique scores for each MPG-disease pair. Components of the score were calculated and weighted for distinctness, integrity, and popularity. Statistical analyses were conducted for the examination of protein-disease relationships. Fourty-four MPGs with known associations to cardiovascular disease and preeclampsia pathways were identified among the 6 diseases. MPGs shared across the greatest number of disease states were implicated in: (1) angiogenesis and vasoconstriction, (2) hemodynamic regulation, (3) hormonal regulation of metabolism, and (4) inflammation. NLP and text phrase-mining are successfully applied to Obstetrics abstracts with accuracy and speed. This approach holds promise in synthesizing large volumes of data for presenting trends in the Obstetric literature and for the identification of promising biomarkers.

Exosomal miR-4516 derived from ovarian cancer stem cells enhanced cisplatin tolerance in ovarian cancer by inhibiting GAS7

Ovarian cancer (OC) is a devastating disease for women, with chemotherapy resistance taking the lead. Cisplatin has been the first-line therapy for OC for a long time. However, the resistance of OC to cisplatin is an important impediment to its efficacy. Mounting studies showed that ovarian cancer stem cells (OCSCs) affected chemotherapy resistance by secreting exosomes. MicroRNAs (miRNAs) play important roles in exosomes secreted by OCSCs. Here, through the analysis of GEO database (GSE107155) combined with RT-qPCR of OC-related cells/clinical tissues, it was found that hsa-miR-4516 (miR-4516) was significantly up-regulated in OCSCs. Then, OCSCs-derived exosomes were isolated and identified, and it was observed the influence of exosomes on the chemoresistance in SKOV3/cisplatin (SKOV3/DDP) cells. These results manifested that OCSCs-mediated exosomes facilitated the chemoresistance of SKOV3/DDP cells by delivering miR-4516 into them. Growth arrest-specific 7 (GAS7), a downstream target of miR-4516, was determined by bioinformatics prediction combined with molecular biological detection. Next, we up-regulated GAS7 expression and discovered that the promotion of chemoresistance in SKOV3/DDP cells by OCSCs-derived exosomes was significantly impaired. Finally, the mice tumor model of SKOV3/DDP cells was built to estimate the effect of GAS7 over-expression on OC growth. The results showed that GAS7 inhibited the chemoresistance of OC in vivo. In conclusion, our experiments suggested that OCSCs-derived exosomes enhanced OC cisplatin resistance by suppressing GAS7 through the delivery of miR-4516. This study provides a possible target for the treatment of OC DDP resistance.

Serum exosomal miR-200c is a potential diagnostic biomarker for breast cancer

BACKGROUND

Breast cancer (BC) is one of the most common malignancies in women. Exosomes are widely found in body fluids and carry microRNAs (miRNAs) that reflect the biological properties of the parental cells. Our study aimed to investigate the differential expression of miR-200c in BC serum exosomes and its diagnostic value.

METHODOLOGY

miRNA profiles in culture supernatant exosomes of normal mammary epithelial cells MCF-10A and BC cells (MCF-7, MDA-MB-231, MCF-7 Taxol) were examined by miRNA deep sequencing to screen for significantly differentially expressed miRNAs; Transmission electron microscopy (TEM), Nanoparticle tracking analysis (NTA), and Western blot were used to identify exosomes; qPCR was used to detect the expression level of miR-200c in cellular exosomes and serum exosomes; The efficacy of individual and combined tests of each indicator to diagnose BC was evaluated using receiver operating characteristic (ROC) curves.

RESULTS

We identified typical exosome features by TEM, NTA and Western blot, indicating successful exosome extraction. Then our miRNA sequencing results and qRT-PCR experiments showed that miR-200c was significantly down-regulated in BC cell exosomes. In addition, we divided the clinical serum samples into two cohorts according to region, and in independent cohort I, the serum exosomal miR-200c levels of BC patients were significantly lower than those of healthy controls. In cohort II, serum exosomal miR-200c expression was significantly lower in the BC group than in the control and benign breast disease (BBD) groups, whereas miR-200c expression in the BBD group was not statistically different from that in the control group. ROC analyses in both independent cohorts confirmed that serum exosomal miR-200c could differentiate between patients with and without BC disease and could be used as an early diagnostic marker for BC disease.

CONCLUSION

Serum exosome miR-200c can be used as a potential biomarker for the diagnosis of BC, and combined with conventional serum diagnostic markers AFP, CA125 and CA153 can help to improve diagnostic efficiency.

MicroRNA-21 (miR-21) in breast cancer: From apoptosis dysregulation to therapeutic opportunities

Breast cancer, a pervasive and complex disease, continues to pose significant challenges in the field of oncology. Its heterogeneous nature and diverse molecular profiles necessitate a nuanced understanding of the underlying mechanisms driving tumorigenesis and progression. MicroRNA-21 (miR-21) has emerged as a crucial player in breast cancer development and progression by modulating apoptosis, a programmed cell death mechanism that eliminates aberrant cells. MiR-21 overexpression is a hallmark of breast cancer, and it is associated with poor prognosis and resistance to conventional therapies. This miRNA exerts its oncogenic effects by targeting various pro-apoptotic genes, including Fas ligand (FasL), programmed cell death protein 4 (PDCD4), and phosphatase and tensin homolog (PTEN). By suppressing these genes, miR-21 promotes breast cancer cell survival, proliferation, invasion, and metastasis. The identification of miR-21 as a critical regulator of apoptosis in breast cancer has opened new avenues for therapeutic intervention. This review investigates the intricate mechanisms through which miR-21 influences apoptosis, offering insights into the molecular pathways and signaling cascades involved. The dysregulation of apoptosis is a hallmark of cancer, and understanding the role of miR-21 in this context holds immense therapeutic potential. Additionally, the review highlights the clinical significance of miR-21 as a diagnostic and prognostic biomarker in breast cancer, underscoring its potential as a therapeutic target.

Circulating biomarkers for diagnosis and response to therapies in cancer patients

Cancer presents a significant challenge to global health, driving worldwide concerted efforts to advance early detection, predict therapeutic response, and identify novel targeted therapies. Liquid biopsies emerge as promising avenues for discerning cancer biomarkers, offering less invasive approaches compared to conventional methods. Utilizing increasingly robust technologies, diverse bodily fluids can unveil genetic variants, epigenetic modifications, transcriptional alterations, and metabolomic signatures associated with cancer, thereby furnishing valuable insights for clinical management. This chapter intends to review the sources of cancer-related biomarkers found in circulation, prevalent techniques utilized for their identification, and the potential implications of different biomarker types on the management of cancer. Certain biomarkers currently used in clinical practice will be addressed, as well as potential biomarkers still in the study phase, and the inherent challenges in their practical implementation.

miR-125 in Breast Cancer Etiopathogenesis: An Emerging Role as a Biomarker in Differential Diagnosis, Regenerative Medicine, and the Challenges of Personalized Medicine

Breast Cancer (BC) is one of the most common cancer types worldwide, and it is characterized by a complex etiopathogenesis, resulting in an equally complex classification of subtypes. MicroRNA (miRNA or miR) are small non-coding RNA molecules that have an essential role in gene expression and are significantly linked to tumor development and angiogenesis in different types of cancer. Recently, complex interactions among coding and non-coding RNA have been elucidated, further shedding light on the complexity of the roles these molecules fulfill in cancer formation. In this context, knowledge about the role of miR in BC has significantly improved, highlighting the deregulation of these molecules as additional factors influencing BC occurrence, development and classification. A considerable number of papers has been published over the past few years regarding the role of miR-125 in human pathology in general and in several types of cancer formation in particular. Interestingly, miR-125 family members have been recently linked to BC formation as well, and complex interactions (competing endogenous RNA networks, or ceRNET) between this molecule and target mRNA have been described. In this review, we summarize the state-of-the-art about research on this topic.

The Epigenetic Landscape of Breast Cancer, Metabolism, and Obesity

Obesity is a risk factor for developing breast cancer, and significantly increases mortality rates in patients diagnosed with this disease. Drivers of this unfortunate relationships are multifactorial, with obesity-induced changes in the epigenetic state of breast cancer cells being identified as a critical mechanism that impact survival, metastasis, and therapeutic responses. Recent studies have investigated the epigenetic landscape of breast cancer to elucidate the molecular interplay between the breast tissue epigenome and its cellular microenvironment. This chapter highlights studies that demonstrates the impact of obesity on the epigenome and metabolome of breast cancer cells. Furthermore, we discuss how obesity impacts the efficacy of chemotherapy and epigenetic targeting drugs, including the emergence of drug-resistance clonal populations. Delineating the relationships between the obesity and epigenetic changes in breast cancer cells will help identify therapeutic strategies which could improve survival outcomes in the rapidly growing number of patients with obesity and cancer.