Normal cells produce adenosine 5′-triphosphate (ATP) mainly through mitochondrial oxidative phosphorylation (OXPHOS) when oxygen is available. Most cancer cells, on the other hand, are known to produce energy predominantly through accelerated glycolysis, followed by lactic acid fermentation even under normoxic conditions. This metabolic phenomenon, known as aerobic glycolysis or the Warburg effect, is less efficient compared with OXPHOS, from the viewpoint of the amount of ATP produced from one molecule of glucose. However, it and its accompanying pathway, the pentose phosphate pathway (PPP), have been reported to provide advantages for cancer cells by producing various metabolites essential for proliferation, malignant progression, and chemo/radioresistance. Here, focusing on a master transcriptional regulator of adaptive responses to hypoxia, the hypoxia-inducible factor 1 (HIF-1), we review the accumulated knowledge on the molecular basis and functions of the Warburg effect and its accompanying pathways. In addition, we summarize our own findings revealing that a novel HIF-1-activating factor enhances the antioxidant capacity and resultant radioresistance of cancer cells though reprogramming of the glucose metabolic pathway.

Objective:To investigate the prognostic value of fluorine-18 fludeoxyglucose (FDG) positron emission tomography (PET) parameters for small-cell lung cancer (SCLC), according to the primary tumour location, adjusted by conventional prognostic factors.Methods:From 2008 to 2013, we enrolled consecutive patients with histologically proven SCLC, who had undergone FDG-PET/CT prior to initial therapy. The primary tumour location was categorized into central or peripheral types. PET parameters and clinical variables were evaluated using univariate and multivariate analysis.Results:A total of 69 patients were enrolled in this study; 28 of these patients were categorized as having the central type and 41 patients as having the peripheral type. In univariate analysis, stage, serum neuron-specific enolase, whole-body metabolic tumour volume (WB-MTV) and whole-body total lesion glycolysis (WB-TLG) were found to be significant in both types of patients. In multivariate analysis, the independent prognostic factor was fo...

This review article comprehensively examines the diagnostic approach to thymic epithelial tumors (TETs) and other mediastinal masses, focusing on imaging modalities and differential diagnosis. Beginning with a discussion on traditional and contemporary classification systems for mediastinal tumors, including the Japanese Association for Research on the Thymus (JART) and International Thymic Interest Group (ITMIG) classifications, it highlights the shift towards computed tomography (CT)-based categorizations. Emphasis is placed on the importance of distinguishing between solid and cystic lesions in the anterior mediastinum, with detailed insights into imaging characteristics and histological features of various TET subtypes such as thymomas, thymic carcinomas, and thymic neuroendocrine tumors (NETs). The review also elucidates common differential diagnoses, including lymphomas and germ cell tumors, providing guidance on key imaging findings and considerations for accurate diagnosis. Furthermore, it underscores the significance of patient background and blood tests in differential diagnosis, discussing age-related prevalence patterns and tumor marker assessment. After addressing the diagnostic challenges posed by thymic cysts offering insights into their radiological features, management considerations, and potential complications, this review extends to other rare mediastinal lesions highlighting the need for a comprehensive evaluation for accurate identification and management of these tumors. Finally, as illustrative examples, we present six cases highlighting various aspects of anterior mediastinal tumors, including TET. These cases provide valuable insights into the diagnostic challenges, imaging characteristics, and management considerations encountered in clinical practice. The cases presented herein do not all illustrate typical images, courses, and diagnoses. However, they each contain significant implications. Thus, we present them with the belief that they will aid in understanding the intricate nuances of image diagnosis in actual clinical practice.