Lidia Perez-Villa

MEK1 (MAP2K1) and MEK2 (MAP2K2) are closely related dual-specificity protein kinases which function by phosphorylating both serine/threonine and tyrosine residues of their substrates ERK1 and ERK2, controlling fundamental cellular processes that include cell growth and proliferation. To investigate the prognostic significance of pMEK expression in the nucleus and cytoplasm among patients with locally advanced head and neck cancer treated with concurrent radiochemotherapy. Immunohistochemistry was performed on the retrieved archival tissue of 96 patients to detect pMEK, p53 and Ki-67. Sixty-six percent of patients were positive for pMEK expression in the nucleus and 41 % in cytoplasm. On univariate analysis, high nuclear pMEK was predictive of worse 5y-DFS and 5y-OS, with a trend to significance (26 % vs. 41 %, p = 0.09; 36 % vs. 47 %, p = 0.07). High cytoplasmic pMEK was predictive of better 5-y OS and 5-y DFS outcomes (61 % vs. 27 %, p = 0.01; 46 % vs. 22 %, p = 0.02). On multivariate analysis, low cytoplasmic pMEK and high nuclear pMEK predicted worse DFS and OS (p = 0.01; p = 0.04 and p = 0.02; p = 0.02 respectively). Subcellular localisation of pMEK has different prognosis in locally advanced head and neck cancer treated with radiochemotherapy.

Preoperative chemoradiotherapy (CRT) is the cornerstone of treatment for locally advanced rectal cancer (LARC). Although high local control is achieved, overall rates of distant control remain suboptimal. Colorectal carcinogenesis is associated with critical alterations of the Wnt/β-catenin pathway involved in proliferation and survival. The aim of this study was to assess whether CRT induces changes in the expression of β-catenin/E-cadherin, and to determine whether these changes are associated with survival.

Introduction: Recurrence risk in breast cancer varies throughout the follow-up time. We examined if these changes are related to the level of expression of the proliferation pathway and intrinsic subtypes. Methods: Expression of estrogen and progesterone receptor, Ki-67, human epidermal growth factor receptor 2 (HER2), epidermal growth factor receptor (EGFR) and cytokeratin 5/6 (CK 5/6) was performed on tissue-microarrays constructed from a large and uniformly managed series of early breast cancer patients (N = 1,249). Subtype definitions by four biomarkers were as follows: luminal A (ER + and/or PR+, HER2-, Ki-67 <14), luminal B (ER + and/or PR+, HER2-, Ki-67 ≥14), HER2-enriched (any ER, any PR, HER2+, any Ki-67), triple-negative (ER-, PR-, HER2-, any Ki-67). Subtype definitions by six biomarkers were as follows: luminal A (ER + and/or PR+, HER2-, Ki-67 <14, any CK 5/6, any EGFR), luminal B (ER + and/or PR+, HER2-, Ki-67 ≥14, any CK 5/6, any EGFR), HER2-enriched (ER-, PR-, HER2+, any Ki-67, any CK 5/6, any EGFR), Luminal-HER2 (ER + and/or PR+, HER2+, any Ki-67, any CK 5/6, any EGFR), Basal-like (ER-, PR-, HER2-, any Ki-67, CK5/6+ and/or EGFR+), triple-negative nonbasal (ER-, PR-, HER2-, any Ki-67, CK 5/6-, EGFR-). Each four- or six-marker defined intrinsic subtype was divided in two groups, with Ki-67 <14% or with Ki-67 ≥14%. Recurrence hazard rate function was determined for each intrinsic subtype as a whole and according to Ki-67 value. Results: Luminal A displayed a slow risk increase, reaching its maximum after three years and then remained steady. Luminal B presented most of its relapses during the first five years. HER2-enriched tumors show a peak of recurrence nearly twenty months post-surgery, with a greater risk in Ki-67 ≥14%. However a second peak occurred at 72 months but the risk magnitude was greater in Ki-67 <14%. Triple negative tumors with low proliferation rate display a smooth risk curve, but with Ki-67 ≥14% show sharp peak at nearly 18 months. Conclusions: Each intrinsic subtype has a particular pattern of relapses over time which change depending on the level of activation of the proliferation pathway assessed by Ki-67. These findings could have clinical implications both on adjuvant treatment trial design and on the recommendations concerning the surveillance of patients.

Cyclooxygenase-2 (COX2) is an enzyme that plays a role in different stages of the carcinogenic process and has prognostic and predictive values that have not yet been established. The objective of this study was to evaluate the role of COX2 overexpression in advanced squamous cell carcinoma of the larynx that has been treated with a phonation conservation protocol.