New treatments and shifting paradigms in differentiated thyroid cancer management.

BACKGROUND: Although most thyroid cancer patients have an excellent prognosis, 10% of low-risk cancers and 25% of high-risk cancers recur, with mortality rates in excess of 50% at 3 years for aggressive thyroid cancer. Traditional paradigms including surgery, I¹³¹ ablation, and TSH suppression do not offer additional therapeutic options for cancers that fail these interventions. Risk stratification and outcomes data are shifting the treatment paradigms to favor more individualized therapies based on risk, and new treatment targets have been identified with promise to treat more aggressive thyroid cancer. METHODS: The authors review the recent literature and published guidelines on thyroid cancer and summarize changing management paradigms and treatments of thyroid cancer. RESULTS: Outcomes data and risk stratification have promoted changes to traditional paradigms. Total/near-total thyroidectomy improves outcomes in both recurrence and mortality. Central compartment lymph node dissection facilitates nodal status determination and likely improves outcomes, while low-risk patients with small tumors are not likely to benefit from I¹³¹ remnant ablation. Early-phase studies have demonstrated significant improvement in progression-free survival with multikinase inhibitors targeting MAPK and angiogenic pathways. CONCLUSIONS: Risk stratification and outcomes data have modified treatment paradigms in thyroid cancer. Patients with progressive thyroid cancer that is no longer surgically resectable or iodine avid should be considered for treatment with multikinase inhibitors, preferably by enrollment in a therapeutic treatment trial.

Effect of actionable somatic mutations on racial/ethnic disparities in head and neck cancer prognosis.

BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide and minorities have the worst survival. However, the molecular mechanisms underlying survival disparities have not been elucidated. METHODS: In a retrospective study, we assessed association between HNSCC early death (<2 years) and 208 somatic mutations of 10 cancer-related genes in 214 patients: 98 non-Hispanic whites (46%), 72 Hispanic whites (34%), and 44 African Americans (20%). RESULTS: Hispanic whites and African Americans had significantly higher mutation rates for EGFR, HRAS, KRAS, and TP53. HNSCC early death was significantly associated with 3+ mutations (odds ratio [OR] = 2.78, 95% confidence interval [CI] = 1.16, 6.69), NOTCH1 mutations in non-Hispanic whites (OR = 5.51; 95% CI = 1.22-24.83) and TP53 mutations in Hispanic whites (OR = 3.84; 95% CI = 1.08-13.68) in multivariable analysis adjusted for age, sex, tumor site, and tumor stage. CONCLUSION: We have provided the proof-of-principal data to link racial/ethnic-specific somatic mutations and HNSCC prognosis and pave the way for precision medicine to overcome HNSCC survival disparities. © 2016 Wiley Periodicals, Inc. Head Neck 38:1234-1241, 2016.

AG490 inhibits G1-S traverse in BALB/c-3T3 cells following either mitogenic stimulation or exogenous expression of E2F-1.

AG490, a member of the tryphostin family of protein kinase inhibitors, repressed G(0)-G(1) traverse in BALB/c-3T3 cells. While the early induction of STAT activity was repressed by AG490, extracellular signal-regulated kinase (ERK) activation was unaffected and a pattern of gene expression suggested that cells exited G(0) in the presence of the inhibitor. Although AG490 did not alter the induction of cyclin D1 protein, neither cyclin D1- nor cyclin D3-associated kinase activity was observed in growth-inhibited cells. Surprisingly, p130 was partially phosphorylated, and E2F3A protein was expressed in mitogen-stimulated AG490-treated cells despite the lack of cyclin D-associated kinase activity. These data suggest that AG490 inhibits a cellular pathway required for mid-G(0)-G(1) traverse that is located after the induction of early processes potentially mediated by E2F (although independent of cyclin D-associated kinase activity) but before the late G(1) increase in E2F-dependent transcription. Infection of AG490-treated cells with an E2F-1 adenovirus caused the induction of cyclin A, but could not overcome the drug-induced cell cycle arrest that was coincident with the repression of cyclin-dependent kinase 2 (cdk2)-associated kinase activation. We conclude that cdk2-associated kinase activity is modulated by a cellular process repressed by AG490. Furthermore, this cdk2-associated kinase activity is required for G(0)-G(1) traverse in some role other than the regulation of E2F-dependent transcription.

Lifelong running reduces oxidative stress and degenerative changes in the testes of mice.

Regular exercise can counteract the adverse effects of aging on the musculoskeletal and cardiovascular systems. In males, the normal aging process is associated with reductions in testosterone production and impaired spermatogenesis, but the underlying mechanisms and their potential modification by exercise are unknown. Here, we report that lifelong regular exercise (running) protects the testes against the adverse effects of advancing age, and that this effect of running is associated with decreased amounts of oxidative damage to proteins, lipids, and DNA in spermatogenic and Leydig cells. Six-month-old male mice were divided into a sedentary group and a group that ran an average of 1.75 km/day, until the mice reached the age of 20 months. Seminiferous tubules of runners exhibited a full complement of cells at different stages of the spermatogenic process and a clear central lumen with large numbers of spermatozoa, in contrast to sedentary mice that exhibited disorganized spermatogenic cells and lacked spermatocytes in a central lumen. Levels of protein carbonyls, nitrotyrosine, lipid peroxidation products, and oxidatively modified DNA were significantly greater in spermatogenic and Leydig cells of sedentary mice compared with runners. These findings suggest that lifelong regular exercise suppresses aging of testes by a mechanism that involves reduced oxidative damage to spermatogenic and Leydig cells.