Basal cell carcinoma and squamous cell carcinoma in a single tumor in the anterior auricular area.

The concurrence of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) in a single tumor is rarely encountered. We report a case of BCC and SCC in a single tumor in the anterior auricular area. A 70-year-old woman had been diagnosed with BCC by a punch biopsy performed at a dermatology clinic. We performed wide excision of the tumor with an ulcer in the anterior auricular area. Analysis of the biopsy specimen revealed the presence of both BCC and SCC in the tumor. This case illustrates that it is necessary to establish a precise diagnosis and formulate appropriate surgical and treatment plans considering the possibility that two carcinomas may coexist, although the possibility is low in patients with skin cancer.

Retroperitoneal leiomyosarcoma mimicking gastric cancer recurrence: A case report.

INTRODUCTION: Leiomyosarcoma is a rare soft tissue cancer that arises from smooth muscle cells that form involuntary muscles. Here, we report a rare case of retroperitoneal leiomyosarcoma that mimicked a metastatic tumor arising from a gastric cancer. PRESENTATION OF CASE: A 43-year-old man underwent radical total gastrectomy for gastric cancer. He underwent adjuvant chemotherapy with oral 5-fluorouracil (5-FU) for 2 years and regular follow-up. Twenty-nine months after gastrectomy, computed tomography (CT) was performed and revealed a solitary localized mass measuring 43 mm in diameter among retroperitoneal lymph nodes of the posterior inferior vena cava. This finding indicated that the previous gastric cancer recurred either in the lymph node or retroperitoneum. Second-line chemotherapy, consisting of oxaliplatin and 5-FU (FOLFOX) was administered in four cycles. However, serial CT scans showed increased tumor size. Retroperitoneal tumor did not respond to treatment, surgical resection was performed. Pathological findings led to a diagnosis of pleomorphic and epithelioid leiomyosarcoma without metastatic adenocarcinoma of the stomach. DISCUSSION: When a diagnosis of locoregional recurrence of gastric cancer in the retroperitoneum is considered, retroperitoneal leiomyosarcoma should also be considered in the differential diagnosis. CONCLUSION: Early diagnosis and concerted therapeutic efforts are important for managing misdiagnosed metastatic gastric cancer.

In Cellulo Mapping of Subcellular Localized Bilirubin.

Bilirubin (BR) is a de novo synthesized metabolite of human cells. However, subcellular localization of BR in the different organelles of human cells has been largely unknown. Here, utilizing UnaG as a genetically encoded fluorescent BR sensor, we report the existence of relatively BR-enriched and BR-depleted microspaces in various cellular organelles of live cells. Our studies indicate that (i) the cytoplasmic facing membrane of the endoplasmic reticulum (ER) and the nucleus are relatively BR-enriched spaces and (ii) mitochondrial intermembrane space and the ER lumen are relatively BR-depleted spaces. Thus, we demonstrate a relationship between such asymmetrical BR distribution in the ER membrane and the BR metabolic pathway. Furthermore, our results suggest plausible BR-transport and BR-regulating machineries in other cellular compartments, including the nucleus and mitochondria.

Proximity-Directed Labeling Reveals a New Rapamycin-Induced Heterodimer of FKBP25 and FRB in Live Cells.

Mammalian target of rapamycin (mTOR) signaling is a core pathway in cellular metabolism, and control of the mTOR pathway by rapamycin shows potential for the treatment of metabolic diseases. In this study, we employed a new proximity biotin-labeling method using promiscuous biotin ligase (pBirA) to identify unknown elements in the rapamycin-induced interactome on the FK506-rapamycin binding (FRB) domain in living cells. FKBP25 showed the strongest biotin labeling by FRB-pBirA in the presence of rapamycin. Immunoprecipitation and immunofluorescence experiments confirmed that endogenous FKBP25 has a rapamycin-induced physical interaction with the FRB domain. Furthermore, the crystal structure of the ternary complex of FRB-rapamycin-FKBP25 was determined at 1.67-Å resolution. In this crystal structure we found that the conformational changes of FRB generate a hole where there is a methionine-rich space, and covalent metalloid coordination was observed at C2085 of FRB located at the bottom of the hole. Our results imply that FKBP25 might have a unique physiological role related to metallomics in mTOR signaling.

Atypical pathogens in adult patients admitted with community-acquired pneumonia in Korea.

This study examined the prevalence of atypical pathogens causing community-acquired pneumonia (CAP) in Korea. We collected sera and clinical data for a period of 1 year for the adult patients consecutively admitted to Chunchon Sacred Heart Hospital with CAP. The diagnosis was made using serologic methods to detect antibodies for Mycoplasma pneumoniae, Chlamydia pneumoniae, Legionella spp., Chlamydia psittaci, and Coxiella burnetii. Among 81 recruited patients, C. pneumoniae (n = 10, 12.3%) was the leading cause of illness, followed by M. pneumoniae (n = 7, 8.6%). One case of C. burnetii pneumonia was detected, but there were no cases of Legionella spp. or C. psittaci. Three cases of C. pneumoniae pneumonia were co-infected with either M. pneumoniae or C. burnetii. There was no significant difference between atypical pneumonia and non-diagnosed pneumonia in terms of clinical manifestations. In conclusion, of the atypical pathogens causing CAP, C. pneumoniae and M. pneumoniae appear to be the important etiologic pathogens in Korea.