Endothelial progenitor cell (EPC)-based stem cell therapy is a promising therapeutic strategy for vascular diseases. However, continuous in vitro expansion for clinical studies induces the loss of EPC functionality due to aging. In this study, we investigated the effects of StemRegenin-1 (SR-1), an antagonist of aryl hydrocarbon receptor (AhR), on replicative senescence in EPCs. We found that SR-1 maintained the expression of EPC surface markers, including stem cell markers, such as CD34, c-Kit, and CXCR4. Moreover, SR-1 long-term-treated EPCs preserved their characteristics. Subsequently, we demonstrated that SR-1 showed that aging phenotypes were reduced through senescence-associated phenotypes, such as β-galactosidase activity, SMP30, p21, p53, and senescence-associated secretory phenotype (SASP). SR-1 treatment also increased the proliferation, migration, and tube-forming capacity of senescent EPCs. SR-1 inhibited the AhR-mediated cytochrome P450 (CYP)1A1 expression, reactive-oxygen species (ROS) production, and DNA damage under oxidative stress conditions in EPCs. Furthermore, as a result of CYP1A1-induced ROS inhibition, it was found that accumulated intracellular ROS were decreased in senescent EPCs. Finally, an in vivo Matrigel plug assay demonstrated drastically enhanced blood vessel formation via SR-1-treated EPCs. In summary, our results suggest that SR-1 contributes to the protection of EPCs against cellular senescence.

There are many preclinical and epidemiological reports suggesting a correlation between 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoAR) or HMG-CoAR inhibitor (statin) treatment and prognosis in breast cancer. This study aimed to investigate the expression of HMG-CoAR in Korean patients with breast cancer. The expression of HMG-CoAR on tissue microarrays from 191 patients who underwent resection from 2005 to 2006 in the Pusan National University Hospital was assessed by immunohistochemistry (IHC). The IHC assessment by a board-certified pathologist included areas of both carcinoma and peritumoral tissue of the breast. The scores of cancer-specific staining were adjusted by the scores of peritumoral staining. The patients were followed for a median 9.1 years. Disease-free survival (DFS) was shorter in patients with a positive adjusted HMG-CoAR score by log-rank test (not reached vs 11.6 years, P = .011). After adjusting for age, T stage, N stage, pathological grade, perioperational chemotherapy, adjuvant radiotherapy, estrogen receptor positivity, progesterone receptor positivity, human epidermal growth factor receptor-2 positivity, and high Ki-67 (>10%), a positive adjusted HMG-CoAR IHC score was also associated with shorter DFS (hazard ratio = 2.638, 95% confidence interval [CI] 1.112–6.262, P = .028). The expression of HMG-CoAR might be an independent prognostic factor in breast cancer. There are established drugs targeting HMG-CoAR, and further studies on its potential as a predictive marker are needed.

This study investigated the protective effect of glutathione (GSH), an antioxidant drug, against doxorubicin (DOX)-induced cardiotoxicity. Human cardiac progenitor cells (hCPCs) treated with DOX (250 to 500 nM) showed increased viability and reduced ROS generation and apoptosis with GSH treatment (0.1 to 1 mM) for 24 h. In contrast to the 500 nM DOX group, pERK levels were restored in the group co-treated with GSH and suppression of ERK signaling improved hCPCs’ survival. Similarly to the previous results, the reduced potency of hCPCs in the 100 nM DOX group, which did not affect cell viability, was ameliorated by co-treatment with GSH (0.1 to 1 mM). Furthermore, GSH was protected against DOX-induced cardiotoxicity in the in vivo model (DOX 20 mg/kg, GSH 100 mg/kg). These results suggest that GSH is a potential therapeutic strategy for DOX-induced cardiotoxicity, which performs its function via ROS reduction and pERK signal regulation.

Primary rhabdomyosarcoma of the breast is very rare disease with poor prognosis and no definitive treatment has yet been established. A 17-year-old girl presented with right breast mass without distant metastasis in image study. The result of core needle biopsy was intraductal carcinoma; however, histopathologic finding after mastectomy was primary rhabdomyosarcoma of breast. Adjuvant chemotherapy was recommended because resection margin was involved by tumor cells, but she did not visit the clinic anymore. Five months later, tumor recurred with local invasion and chemotherapy of vincristine, doxorubicin, and cyclophosphamide alternating with ifosfamide and etoposide (VAC/IE) was done. In the course of chemotherapy and sequential follow-up, there was no tumor growth until now. Primary breast rhabdomyosarcoma is an uncommon disease, as a result diagnosis is often delayed. For the same reason, there is little information about treatment. This report may be helpful for managing the disease.

Female breast cancer is among the most prevalent cancers globally, often metastasizing to the brain. Despite advancements in treatment, brain metastasis incidence is rising, with a poor prognosis. Moreover, limited data exist on how breast cancer subtypes and patient characteristics impact survival. This study aimed to investigate prognostic factors affecting breast cancer patients with brain metastasis. We retrospectively reviewed 131 breast cancer patients with brain metastasis diagnosed at a single institution between 2010 and 2020. Demographic, clinical, pathological, and radiographic variables were analyzed. The median interval between breast cancer diagnosis and brain metastasis was 27 months. Patients diagnosed with a higher stage of breast cancer (median survival: stage 1: 97.2 months, stage 2: 44.4 months, stage 3: 38.1 months, stage 4: 13.0 months, P < .001) and those with ER-negative tumors (median survival: negative 25.3 months, positive 37.5 months, P = .034) had a shorter time between initial diagnosis and brain metastasis. Median survival after brain metastasis was 8.0 months. Multivariate analysis showed that triple-negative breast cancer was correlated to a high risk of death after brain metastasis (hazard ratio = 2.320, P < .001). Higher histological grade, low-performance status, extensive brain metastases, and leptomeningeal seeding was associated with shorter survival. Systemic chemotherapy after brain metastasis was the only treatment that improved survival (hazard ratio = 0.332, P < .001). The study suggests potential benefits of aggressive treatment, especially in nontriple-negative breast cancer subtypes, limited brain metastases, and good overall health. Further research with larger patient populations is needed.

The purpose of this study was to evaluate the efficacy and safety of rivaroxaban for the treatment of cancer-associated venous thromboembolism (VTE). We performed a retrospective chart review of cancer patients with a pulmonary embolism, deep vein thrombosis, or both. Our analysis included all patients who received rivaroxaban from March 2013 to June 2016 at the Hemato-Oncology Division at the Pusan National University Hospital in Korea. Preliminary results identified 123 patients with a history of cancer that were treated with rivaroxaban. The average duration of rivaroxaban therapy was 95.25 days. While 35 patients had resolved VTE after the initiation of rivaroxaban, only one patient had it recur on rivaroxaban treatment. Major bleeding was observed in 6 (4.9%) patients and minor bleeding in 12 (9.8%) patients. The majority of bleeding events occurred spontaneously and most incidences of bleeding could be treated conservatively. Recurrence and major bleeding events on rivaroxaban were relatively low despite the fact that many patients had metastatic disease. Among 52 patient deaths (42.3%), none were due to VTE or bleeding complications; the cause of death in the majority of cases was cancer progression. Rivaroxaban is effective and safe for the treatment of cancer-associated VTE.