Song-Yi Choi

Triple-negative breast cancer (TNBC) exhibits diverse histological and molecular characteristics. TNBC patients also have the poorest prognoses among those with various breast cancer subtypes, and no effective treatment strategy has been established for TNBC beyond non-specific chemotherapy. Recent studies have reported that the dysregulation of miRNAs is associated with tumor behavior, prognosis, and treatment responses in TNBC patients. Therefore, this study was conducted to identify miRNAs and key target proteins potentially associated with TNBC prognosis. Fresh-frozen tissue from relapsing and non-relapsing TNBC cases was examined for differentially expressed miRNAs using the Affymetrix GeneChip miRNA 4.0 array, while target genes and proteins were predicted using the miRwalk 2.0 database. The clinical significance of each differentially expressed miRNA was evaluated using the BreastMark database. Additional bioinformatics analyses were conducted to reveal associations with tumor-related signaling pathways; these analyses included protein–protein interaction network construction and Kyoto Encyclopedia of Genes and Genomes pathway annotation. Gene chip analysis identified three upregulated miRNAs (miR-500a, miR-501-3p, and miR-502-3p) and two downregulated miRNAs (miR-6798-5p and miR-7150) in patients with recurrence, and further bioinformatics analyses revealed that target proteins were significantly associated with cell cycle pathways. In addition, low expression of the miR-500a target protein UBE2Z was significantly associated with a poor prognosis. The expression levels of miR-500a and UBE2Z might be useful prognostic biomarkers in TNBC.

Gradual progressive weakness in a patient with diabetes mellitus can be caused by several conditions, including myelopathy, motor neuron disease, chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), and myopathy. Diagnosing the exact cause of progressive muscle weakness can be challenging in the presence of diabetic polyneuropathy (DPN). We report a case of CIDP with DPN in a 64-year-old woman who was initially misdiagnosed with amyotrophic lateral sclerosis. This case also demonstrates the importance of using the correct dose and duration for the treatment of CIDP.

It has been known that infection plays a role in the development of hypertension. However, the role of hypertension in the progression of infectious diseases remain unknown. Many countries with high rates of hypertension show geographical overlaps with those showing high incidence rates of tuberculosis (TB). To explore the role of hypertension in tuberculosis, we compared the effects of hypertension during mycobacterial infection, we infected both hypertensive Angiotensin II (Ang II) and control mice with Mycobacterium tuberculosis (Mtb) strain H37Ra by intratracheal injection. Ang II-induced hypertension promotes cell death through both apoptosis and necrosis in Mtb H37Ra infected mouse lungs. Interestingly, we found that lipid accumulation in pulmonary tissues was significantly increased in the hypertension group compared to the normal controls. Ang II-induced hypertension increases the formation of foamy macrophages during Mtb infection and it leads to cell death. Moreover, the hypertension group showed more severe granuloma formation and fibrotic lesions in comparison with the control group. Finally, we observed that the total number of mycobacteria was increased in the lungs in the hypertension group compared to the normal controls. Taken together, these results suggest that hypertension increases intracellular survival of Mtb through formation of foamy macrophages, resulting in severe pathogenesis of TB.

The Jeju horse is a native Korean species that has been breeding on Jeju Island since the 13th century. Their shape has a distinct appearance from the representative species, Thoroughbred. Here, we performed a comparison of the Jeju horse and Thoroughbred horse for the identification of genome-wide structure variation by using the next-generation sequencing (NGS) technique. We generated an average of 95.59 Gb of the DNA sequence, resulting in an average of 33.74 X sequence coverage from five Jeju horses. In addition, reads obtained from WGRS data almost covered the horse reference genome (mapped reads 98.4%). Based on our results, we identified 1,244,064 single nucleotide polymorphisms (SNPs), 113,498 genomic insertions, and 114,751 deletions through bioinformatics analysis. Interestingly, the results of the WGRS comparison indicated that the eqCD1a6 gene contains signatures of positive natural selection in Jeju horses. The eqCD1a6 gene is known to be involved in immunity. The eqCD1a6 gene of Jeju horses commonly contained 296 variants (275 SNPs and 21 INDELs) that were compared with its counterpart of two Thoroughbred horses. In addition, we used LOAA, digital PCR, to confirm the possibility of developing a molecular marker for species identification using variant sites. As a result, it was possible to confirm the result of the molecular marker with high accuracy. Nevertheless, eqCD1a6 was shown to be functionally intact. Taken together, we have found significant genomic variation in these two different horse species.

Identifying the patterns of gene expression in breast cancers is essential to understanding their pathophysiology and developing anticancer drugs. Breast cancer is a heterogeneous disease with different subtypes determined by distinct biological features. Luminal breast cancer is characterized by a relatively high expression of estrogen receptor (ER) and progesterone receptor (PR) genes, which are expressed in breast luminal cells. In ~25% of invasive breast cancers, human epidermal growth factor receptor 2 (HER2) is overexpressed; these cancers are categorized as the HER2 type. Triple-negative breast cancer (TNBC), in which the cancer cells do not express ER/PR or HER2, shows highly aggressive clinical outcomes. TNBC can be further classified into specific subtypes according to genomic mutations and cancer immunogenicity. Herein, we discuss the brief history of TNBC classification and its implications for promising treatments.

변승희, et al. J Korean Soc Radiol. 2020 Dec;82:e1. https://doi.org/10.3348/jksr.2020.0008

Background Triple-negative breast cancer (TNBC) is a heterogeneous entity that encompasses several subtypes with distinct molecular characteristics. The patients with TNBCs show unpredictable response to the chemotherapy, and further there is the lack of effective agents. Thus, many studies have been underway to discover targeted therapy suitable for patients with specific genetic alterations in each molecular subtypes. TNBCs are classified as four major molecular subtypes according to the gene expression patterns. These are luminal androgen receptor (LAR), mesenchymal-like, immunomodulatory (IM), and basal-like types. Conclusion Here, we discuss the unique molecular features of each subtype as well as promising targets for anti-cancer therapy.

Due to the rare occurrence of young-onset bladder cancer (YBC), its genomic characteristics remain largely unknown. Twenty-nine biopsy-proven YBC cases were collected using a nation-wide search for bladder cancer diagnosed at 20 years or younger. Whole exome sequencing and RNA sequencing were carried out in 21 and 11 cases, respectively, and compared with those of adult bladder cancer (ABC) cases obtained from public databases. Almost all YBCs were low grade, non-invasive papillary tumors. YBC had a low mutation burden and less complex copy number alterations. All cases harbored putative driver mutations. Mutations were most commonly found in HRAS (10 cases), with a preference for exon 5. FGFR3 gene fusions were noted with various partner genes (7 cases). The alterations on HRAS and FGFR3 occurred in a mutually exclusive manner. Others included KRAS mutations (2 cases), chromosomes 4p and 10q arm-level deletions (1 case), and ERCC2 mutation (1 case). There were no point mutations in TP53 and FGFR3. The gene expression profiles of YBC were similar to those of the ABC group with good prognosis. None of the YBCs and ABCs with YBC-like mutations showed progression to muscle-invasive tumors. Our results suggest that bladder cancer with YBC-like mutations represents an indolent bladder tumor, regardless of age.