Yong Sung Won

Significance of CD133 as a cancer stem cell markers focusing on the tumorigenicity of pancreatic cancer cell lines

Purpose The cancer stem cell hypothesis states that the capacity of a cancer to grow and propagate is dependent on a small subset of cells. To determine the significances of the cancer stem cell markers CD133, CD44, and CD24 using a comparative analysis with a focus on tumorigenicity. Methods Four pancreatic cancer cell lines, Capan-1, Mia-PACA-2, Panc-1, and SNU-410 were analyzed for the expressions of CD133, CD44, and CD24 by flow cytometry. The tumorigenicity was compared using tumor volumes and numbers of tumors formed/numbers of injection in nonobese diabetic severe combined deficiency mice. Fluorescence-activated cell sorting (FACS) analysis was used to confirm that xenograft explants originated from human pancreatic cancer cells. Results CD133 was positive in only Capan-1, CD44 positive in all, CD24 partially positive in Panc-1. After injecting 2 × 106 cells, all mice administered Capan-1 or Mia-Paca-2 developed tumors, 3 of 5 administered Panc-1 developed tumors, but no mouse administered SNU-410 developed any tumors. The volumes of Capan-1 tumors were seven times larger than those of Mia-Paca-2 tumors. When 2 × 105 or 2 × 104 of Capan-1 or Mia-Paca-2 was injected, tumors developed in all Capan-1 treated mice, but not in Mia-Paca-2 treated mice. Furthermore, xenograft explants of Capan-1 expressed CD133+CD44+ and Capan-1 injected mice developed lung metastasis. FACS analysis showed that xenograft explants originated from human pancreatic cancer cell lines. Conclusion CD133 positive cells have higher tumorigenic and metastatic potential than CD44 and CD24 positive cells, which suggests that CD133 might be a meaningful cell surface marker of pancreatic cancer stem cells.

Prognostic Significance of HER2 Gene Amplification According to Stage of Breast Cancer

It is well known that the amplification of the HER2 gene is closely associated with poor prognosis of breast cancer. However, there is controversy about the clinical significance of HER2 according to lymph node status in breast cancer. The aim of this study was to identify the differences in the prognostic significance of HER2 gene amplification according to the stages of breast cancer. We prepared a tissue array for fluorescence in situ hybridization (FISH) with breast cancer specimens from the surgery in 1994 to 1999. Total 338 cases of breast cancer were enrolled and the median follow-up period was 6.3 yr. The detection rates of HER2 gene amplification were as follows: 10.3% in stage I, 22.3% in stage II, and 43.8% in stage III. On survival analyses HER2-positive groups showed worse prognosis in stage III of breast cancer, but not in stage I or II. Multivariate analyses with a Cox-regression model also revealed that HER2 amplification was an independent prognostic factor only in stage III breast cancer. Regarding HER2 gene amplification as a prognostic factor of breast cancer, the clinical significance of the gene was found to be confined to advanced breast cancer.

A case of Riedel's thyroiditis associated with benign nodule: mimic of anaplastic transformation.

Riedels thyroiditis is a rare variant of thyroiditis and characterized by the replacement of thyroid parenchyma by extensive fibrosis. Typically, the thyroid is diffusely involved and a painless, hard anterior neck mass shows clinical features similar to those of anaplastic thyroid carcinoma: a rapidly enlarging, hard, fixed thyroid mass and symptoms such as dysphagia, dysphonia, and dyspnea. We experienced a case of Riedels thyroiditis that had presented rapidly growing, hard, fixed, thyroid mass mimicking anaplastic thyroid cancer in a 41-year-old female patient with longstanding benign thyroid nodule for 6 years. The clinical features were indistinguishable from that of anaplastic transformation and open biopsy could exclude anaplastic thyroid cancer. After surgery final diagnosis of Riedels thyroiditis could be made by typical microscopic findings and immunohistochemical studies. We reported the case with review of the related literatures.

Solid pseudopapillary tumor with hepatic metastasis

Solid pseudopapillary tumor of the pancreas is a rare tumor that affects young females with low malignant potential and good prognosis with more than 90% survival at 5 years. Metastasis is very rare. We report the case of a 74-year-old female who had pancreatic solid-pseudopapillary tumor and synchronous hepatic metastasis.

Current trends of major arterial diseases in Korea: based on data from the Health Insurance Review and Assessment Service

Purpose This study aims to figure out the changes of the prevalence and management of carotid arterial occlusive diseases (CAOD), abdominal aortic diseases (AAA), and arterial diseases of the lower extremities (LAOD) in Korea over the past 5 years. Methods Data were extracted from the Health Insurance Review and Assessment Service during the period from 2008 to 2012. Results The number of patients with CAOD increased by about 30% every year. From the year 2008, the number of open surgeries (OS) and endovascular treatments (ET) increased by more than 20% during each of the first 2 years and by 10% every year for 3 years thereafter for CAOD. ET was preferred to OS and occupied 77%–79% of the total number of procedures. The number of patients with AAA increased by 11%–17% every year. ET for AAA occupied 52% of the total number of procedures in 2008 and gradually increased to 70% in 2012. The number of patients who were diagnosed with LAOD fluctuated over the five years. The total number of procedures to treat LAOD increased each year by 20%–25%. ET for LAOD constantly increased by 18%–24% each year and occupied 80%–95% of the total number of procedures. Conclusion It is evident that the incidence of vascular diseases will be increasing as our society ages, not to mention its care costs. The need for long-range plans and guidelines are urgent.