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Like other cancers, renal cell carcinoma (RCC) derives the essential energy for proliferation and survival from high rates of glycolysis rather than from oxidative phosphorylation of the mitochondrial respiration pathway. NDUFA4 (NADH Dehydrogenase (Ubiquinone) 1 Alpha Subcomplex, 4) is encoding a protein belonging to the respiratory chain of mitochondria. For a better understanding of the tumor biology and for identification of a potential new biomarker, we analyzed the regulation of NDUFA4 in RCC compared to normal tissue cells. Downregulation of NDUFA4 mRNA and protein was detected in RCC compared to normal renal tissues in quantitative real-time PCR as well as in western blot and immunohistochemical staining. Histological analysis revealed higher NDUFA4 expression in the distal tubules compared to the proximal tubules and the loop of Henle. A higher molecular weight of the NDUFA4 protein was discovered in RCC samples, possibly indicating a posttranslational modification. Moreover, NDUFA4 protein expression was predictive for cancer-specific survival. Our analysis revealed a potential new biomarker, but future studies are warranted to investigate the prognostic value of NDUF4A expression.

Small-cell lung cancer (SCLC) is an aggressive lung tumor subtype with poor prognosis(1-3). We sequenced 29 SCLC exomes, 2 genomes and 15 transcriptomes and found an extremely high mutation rate of 7.4 +/- 1 protein-changing mutations per million base pairs. Therefore, we conducted integrated analyses of the various data sets to identify pathogenetically relevant mutated genes. In all cases, we found evidence for inactivation of TP53 and RB1 and identified recurrent mutations in the CREBBP, EP300 and MLL genes that encode histone modifiers. Furthermore, we observed mutations in PTEN, SLIT2 and EPHA7, as well as focal amplifications of the FGFR1 tyrosine kinase gene. Finally, we detected many of the alterations found in humans in SCLC tumors from Tp53 and Rb1 double knockout mice(4). Our study implicates histone modification as a major feature of SCLC, reveals potentially therapeutically tractable genomic alterations and provides a generalizable framework for the identification of biologically relevant genes in the context of high mutational background.

Acquired chromosomal aberrations, including gene copy number alterations, are involved in the development and progression of human malignancies. SOX2, a transcription factor-coding gene located at 3q26.33, is known to be recurrently and specifically amplified in squamous cell carcinomas of the lung, the esophagus, and the oral cavity. In these organs, the SOX2 protein plays an important role in tumorigenesis and tumor survival. The aim of this study was to determine whether SOX2 amplification is also found in squamous cell carcinomas in other organs commonly affected by this tumor entity. In addition, we examined a large spectrum of lung cancer entities with neuroendocrine differentiation (ie, small cell cancers, large cell cancers, typical and atypical carcinoids) for SOX2 and TTF1 copy number gains to reveal potential molecular ties to squamous cell carcinomas or adenocarcinomas of the lung. Applying fluorescence in situ hybridization, we assessed squamous cell carcinomas of the cervix uteri (n = 47), the skin (n = 57), and the penis (n = 53) for SOX2 copy number alterations and detected amplifications in 28%, 28%, and 32% of tumors, respectively. Furthermore, we performed immunohistochemical SOX2 staining and found that SOX2 amplification is significantly associated with overexpression of the corresponding protein in squamous cell carcinomas (P < .001). Of the lung cancer entities with neuroendocrine differentiation, only small cell cancers and large cell cancers exhibited SOX2 or TTF1 amplifications at significant frequencies, indicating that at least a subset of these might be dedifferentiated forms of squamous cell carcinomas or adenocarcinomas of the lung. We conclude that SOX2 amplification and consequent SOX2 protein overexpression may represent important mechanisms of tumor initiation and progression in a considerable subset of squamous cell carcinomas.

Purpose Gleason grading is an important predictor of prostate cancer (PCa) outcomes. Studies using surrogate PCa end points suggest outcomes for Gleason score (GS) 7 cancers vary according to the predominance of pattern 4. These studies have influenced clinical practice, but it is unclear if rates of PCa mortality differ for 3 + 4 and 4 + 3 tumors. Using PCa mortality as the primary end point, we compared outcomes in Gleason 3 + 4 and 4 + 3 cancers, and the predictive ability of GS from a standardized review versus original scoring. Patients and Methods Three study pathologists conducted a blinded standardized review of 693 prostatectomy and 119 biopsy specimens to assign primary and secondary Gleason patterns. Tumor specimens were from PCa patients diagnosed between 1984 and 2004 from the Physicians' Health Study and Health Professionals Follow-Up Study. Lethal PCa (n = 53) was defined as development of bony metastases or PCa death. Hazard ratios (HR) were estimated according to original GS and standardized GS. We compared the discrimination of standardized and original grading with C-statistics from models of 10-year survival. Results For prostatectomy specimens, 4 + 3 cancers were associated with a three-fold increase in lethal PCa compared with 3 + 4 cancers (95% CI, 1.1 to 8.6). The discrimination of models of standardized scores from prostatectomy (C-statistic, 0.86) and biopsy (C-statistic, 0.85) were improved compared to models of original scores (prostatectomy C-statistic, 0.82; biopsy C-statistic, 0.72). Conclusion Ignoring the predominance of Gleason pattern 4 in GS 7 cancers may conceal important prognostic information. A standardized review of GS can improve prediction of PCa survival.