Allelic loss at 16q23.2 is associated with good prognosis in high grade prostate cancer

Genetic signatures of HPV-related and unrelated oropharyngeal carcinoma and their prognostic implications

PURPOSE

Patients with human papillomavirus (HPV)-containing oropharyngeal squamous cell carcinomas (OSCC) have a better prognosis than patients with HPV-negative OSCC. This may be attributed to different genetic pathways promoting cancer.

EXPERIMENTAL DESIGN

We used comparative genomic hybridization to identify critical genetic changes in 60 selected OSCC, 28 of which were associated with HPV-16 as determined by HPV-specific PCR and fluorescence in situ hybridization analysis and positive p16(INK4A) immunostaining. The results were correlated with HPV status and clinical data from patients.

RESULTS

Two thirds of OSCC harbored gain at 3q26.3-qter irrespective of HPV status. In HPV-negative tumors this alteration was associated with advanced tumor stage (P=0.013). In comparison with HPV-related OSCC, the HPV-negative tumors harbored: (a) a higher number of chromosomal alterations and amplifications (P=0.03 and 0.039, respectively); (b) significantly more losses at 3p, 5q, 9p, 15q, and 18q, and gains/amplifications at 11q13 (P=0.002, 0.03; <0.001, 0.02, 0.004, and 0.001, respectively); and (c) less often 16q losses and Xp gains (P=0.02 and 0.03). Survival analysis revealed a significantly better disease-free survival for HPV-related OSCC (P=0.02), whereas chromosome amplification was an unfavorable prognostic indicator for disease-free and overall survival (P=0.01 and 0.05, respectively). Interestingly, 16q loss, predominantly identified in HPV-related OSCC, was a strong indicator of favorable outcome (overall survival, P=0.008; disease-free survival, P=0.01) and none of these patients had a tumor recurrence.

CONCLUSIONS

Genetic signatures of HPV-related and HPV-unrelated OSCC are different and most likely underlie differences in tumor development and progression. In addition, distinct chromosomal alterations have prognostic significance.

Genomic biomarkers, androgen pathway and prostate cancer

Prostate cancer is the most frequent male malignancy diagnosed in western countries and the second leading cause of cancer-related deaths. The growth and function of the prostate gland depends on androgens. Owing to the importance of androgens in prostate development, genes involved in androgen biosynthesis and metabolism have been extensively studied. In this review, we address recent progress toward the use of inherited and acquired genetic variants to predict susceptibility and clinical outcomes of prostate cancer patients. Many of these genetic variants involve several genes related to the biosynthesis and metabolism of androgens, such as steroid-5-α-reductase, α polypeptide 2 (SRD5A2), cytochrome P450 (CYP)19A1, CYP17A1, hydroxy-δ-5-steroid dehydrogenase, 3 β- and steroid δ-isomerase 2 (HSD3B2) and androgen receptor (AR). With increasing knowledge, it may be possible to distinguish indolent from aggressive prostate tumors by molecular fingerprinting. Furthermore, with the emergence of new investigative tools, such as microarray platforms and comparative genomic hybridization (CGH) array, a variety of new genomic biomarkers will be available in the future to provide accurate prognostic and monitoring solutions for individualized patient care.

The clinical relevance of microsatellite alterations in head and neck squamous cell carcinoma: a critical review

Triggered by the existing confusion in the field, the current paper aimed to review the current knowledge of both microsatellite instability (MSI) and loss of heterozygosity (LOH) detected by microsatellite markers in head and neck squamous cell carcinoma (HNSCC), and to provide the reader with an assessment of their prognostic and predictive value in this tumor type. For both MSI and LOH, various detection methods were included such as mono- and polynucleotidemarkers and gel- as well as automated analyses. Only studies based on PCR techniques with microsatellite markers were considered. Taking the methodological problems occurring in investigations with microsatellite markers into account, LOH seems to be more common than MSI in HNSCC. Although both types of microsatellite alterations have been correlated with clinicopathological features of this tumor type, only LOH seems to have a clear prognostic value. The predictive value of both MSI and LOH is debatable. More research has to be performed to clearly establish LOH detection as a translational application in the HNSCC field, aiming to predict response to treatments or outcome, and eventually to use as a therapeutic target.

BCAR1 expression in prostate cancer: association with 16q23 LOH status, tumor progression and EGFR/KAI1 staining

BACKGROUND

The 16q23 locus has been recently suggested in both breast and prostate cancer to contain a gene involved in disease progression. The breast cancer antiestrogen resistance 1 (BCAR1) gene, located at 16q23, contributes to many cellular processes including migration and survival, and interacts in vitro with the growth factor receptor EGFR and the metastasis suppressor KAI1.

METHODS

BCAR1, EGFR, and KAI1 expression was studied by immunohistochemistry on a tissue microarray containing 100 localized prostate cancers (LPC), 15 hormone refractory prostate cancers (HRPC), and 15 lymph node metastasis (LNM). Forty eight of the LPC were also analyzed for 16q23 LOH status using microsatellite markers.

RESULTS

BCAR1 staining was present in 25% of LPC, associated with higher Gleason score, and in 60% and 80% of, respectively, LNM and HRPC. BCAR1 expression was inversely correlated with 16q23 LOH status (P < 0.001), and was associated with high EGFR staining (P < 0.02), and negative KAI1 expression (P < 0.01).

CONCLUSIONS

BCAR1 expression in LPC seems to be regulated at least in part by genetic events. The increased expression of BCAR1 with disease progression suggests a potential interest for both prognosis and treatment.