Diagnostic performance of Midkine ratios in fine-needle aspirates for evaluation of Cytologically indeterminate thyroid nodules

Midkine promotes thyroid cancer cell migration and invasion by activating the phosphatidylinositol 3 kinase/protein kinase B/mammalian target of rapamycin pathway

Objective

Thyroid cancer (TC) therapy, which is routinely used at present, can improve patients' survival rates. However, lymph node metastasis results in a higher degree of TC malignancy in patients who experience recurrence and/or death. The elucidation of new mechanisms of TC metastasis can help identify new therapeutic targets. Midkine (MDK) is expressed aberrantly in various cancers. However, the regulatory mechanisms of MDK in TC remain largely unknown. Hence, this study mainly explores the effect and molecular function of MDK in TC.

Material and Methods

MDK gene expression and protein levels were analyzed using the Gene Expression Profiling Interactive Analysis and the Human Protein Atlas online databases. MDK messenger RNA (mRNA) in TC was analyzed by quantitative real-time polymerase chain reaction. MDK, phosphatidylinositol 3 kinase (PI3K), phosphorylated AKT (p-AKT), and phosphorylated mammalian target of rapamycin (p-mTOR) protein in TC were analyzed by Western blotting. Transwell and wound healing assays were performed to evaluate TC cell metastasis.

Results

MDK mRNA was significantly highly expressed in most patients with TC (P < 0.05). Moreover, MDK gene expression levels correlated with different TC stages. MDK protein was negative in normal tissues and positive in TC tissues. MDK mRNA and protein were significantly highly expressed in TC cells (P < 0.01). Compared with metastasis in the control group, that in the MDK group is significantly suppressed by MDK knockdown (P < 0.001). MDK knockdown also significantly inhibited PI3K, p-AKT, and p-mTOR protein expression in TPC-1 and K1 cells (P < 0.001). The activation of PAmT-P significantly enhanced the PI3K, p-AKT, and p-mTOR protein expression in TPC-1 and K1 cells (P < 0.001) and promoted metastasis (P < 0.001), thereby disrupting the inhibitory effect of the MDK knockdown.

Conclusion

Our findings confirmed that MDK promotes TC migration and invasion by activating PAmT-P. MDK is a novel molecular target for the treatment of patients with metastatic TC.

NF1 mutation-driven neuronal hyperexcitability sets a threshold for tumorigenesis and therapeutic targeting of murine optic glioma

BACKGROUND

With the recognition that noncancerous cells function as critical regulators of brain tumor growth, we recently demonstrated that neurons drive low-grade glioma initiation and progression. Using mouse models of neurofibromatosis type 1 (NF1)-associated optic pathway glioma (OPG), we showed that Nf1 mutation induces neuronal hyperexcitability and midkine expression, which activates an immune axis to support tumor growth, such that high-dose lamotrigine treatment reduces Nf1-OPG proliferation. Herein, we execute a series of complementary experiments to address several key knowledge gaps relevant to future clinical translation.

METHODS

We leverage a collection of Nf1-mutant mice that spontaneously develop OPGs to alter both germline and retinal neuron-specific midkine expression. Nf1-mutant mice harboring several different NF1 patient-derived germline mutations were employed to evaluate neuronal excitability and midkine expression. Two distinct Nf1-OPG preclinical mouse models were used to assess lamotrigine effects on tumor progression and growth in vivo.

RESULTS

We establish that neuronal midkine is both necessary and sufficient for Nf1-OPG growth, demonstrating an obligate relationship between germline Nf1 mutation, neuronal excitability, midkine production, and Nf1-OPG proliferation. We show anti-epileptic drug (lamotrigine) specificity in suppressing neuronal midkine production. Relevant to clinical translation, lamotrigine prevents Nf1-OPG progression and suppresses the growth of existing tumors for months following drug cessation. Importantly, lamotrigine abrogates tumor growth in two Nf1-OPG strains using pediatric epilepsy clinical dosing.

CONCLUSIONS

Together, these findings establish midkine and neuronal hyperexcitability as targetable drivers of Nf1-OPG growth and support the use of lamotrigine as a potential chemoprevention or chemotherapy agent for children with NF1-OPG.

Thyroid Nodules: Emerging Trends in Detection and Visualization based on Citespace

BACKGROUND

Thyroid nodule (TN) is a highly prevalent clinical endocrine disease. Many countries have formed guidelines on the prevention and treatment of TN based on extensive research. However, there is a scarcity of TN-related literature based on bibliometrics.

OBJECTIVES

This study aimed to evaluate the scientific achievements and progress of TN research from a global perspective by investigating the literature for 20 years through bibliometrics.

METHODS

We searched the literature on TN in the core collection of the Web of Science database from 2002 to 2021 and used the Citespace software to analyze the co-authorship, co-citation, and co-occurrence of countries, institutions, authors, keywords, and co-cited literature.

RESULTS

We retrieved 12319 documents related to TN. The literature on TN has been growing since 2002. The United States has contributed the largest proportion of TN papers (20.64%), followed by China, Italy, and South Korea. The United States ranked first in terms of centrality (0.38). Haugen BR, Gharib H, and Cibas ES are the top three most cited authors. The papers published in Thyroid were cited most frequently (7952 times). The most prominent keywords were management, cancer, fine needle aspiration, diagnosis, malignant tumor, thyroid cancer, ultrasound, biopsy, benign, surgery, ablation, and cytology. All keywords could be divided into three categories: diagnosis stratification, treatment, and cancer. As far as potential hot spots are concerned, the keywords that have recently burst strongly and are still continuing are: "Association Guideline" (2018-2021), "Radiofrequency Ablation" (2017-2021), "Classification" (2019-2021), and "Data System" (2017-2021).

CONCLUSION

Based on the current trends, the number of publications on TN will continue to increase. The United States is the most active contributor to research in this field. Previous literature focused on stratification, cancer, surgery, and ablation, and there were different opinions on the stratification of diagnosis. There were relatively few studies on pathogenesis and treatment using medicine. More focus will be placed on association guidelines, radiofrequency ablation, classification, and data system, which may be the next popular topics in TN research.