Age Differences in Types and Perceptions of Daily Stress.

The present study explores differences in daily stress across individuals of varying ages. Specifically, we explore whether age group (young adult, midlife, late midlife, later life) relates to differences in types of stress (family, friends, partner, health, finances, work), total stress exposure, and perceptions of daily stress intensity. Participants from the Notre Dame Study of Health & Well-being (NDHWB; N = 891) completed daily questionnaires assessing negative small life events and perceived stress for 8 weeks. Findings indicated that young adults reported a higher average number of family, spouse, finance, and work-related stress. Additionally, total daily stress was highest among young adults, and perceived stress was lowest among later life adults. Because daily stress relates to long-term mental and physical stress, gaining a better understanding of how individuals at different points in the life span uniquely experience stress can inform intervention and preventative care techniques aimed at promoting optimal well-being.

Dual inhibition of the PI3K and MAPK pathways enhances nab-paclitaxel/gemcitabine chemotherapy response in preclinical models of pancreatic cancer.

Standard chemotherapy for pancreatic ductal adenocarcinoma (PDAC), nab-paclitaxel (NPT) plus gemcitabine (Gem), has led to an average survival of 8.5 months. Presently, no therapeutics exist that effectively target the KRAS oncogene, activated in 95% of PDACs, but alternative strategies focus on inhibition of downstream effectors of KRAS signaling. Through combined inhibition of PI3K and MAPK signaling with MK-2206 (MK) and trametinib (Tra), enhancement of NPT + Gem response was evaluated. Median animal survival was significantly improved by the NPT + Gem combination (67% increase). Addition of MK-2206 or trametinib further increased median survival: NPT + Gem + MK (86%), NPT + Gem + Tra (105%), and NPT + Gem + MK + Tra (129%). In cell line-derived xenografts, the net tumor growth (in mm3) compared to controls (878.5) was significantly reduced by NPT + Gem (191.2), NPT + Gem + MK (150.7), NPT + Gem + Tra (62.2) and NPT + Gem + MK + Tra (49.9) therapies. In patient-derived xenografts, the combination of MK-2206 and trametinib with chemotherapy had an additive response in reducing tumor growth. Effects of therapy on tumor cell proliferation and apoptosis corresponded with tumor growth inhibition. These findings suggest that the standard chemotherapy response of PDAC can be enhanced through dual targeting of PI3K and MAPK signaling, which could lead to improved PDAC therapy.

Inhibition of the MEK/ERK pathway augments nab-paclitaxel-based chemotherapy effects in preclinical models of pancreatic cancer.

Nab-paclitaxel (NPT) combination with gemcitabine (Gem) represents the standard chemotherapy for pancreatic ductal adenocarcinoma (PDAC). Genetic alterations of the RAS/RAF/MEK/ERK (MAPK) signaling pathway yielding constitutive activation of the ERK cascade have been implicated as drivers of PDAC. Inhibition of downstream targets in the RAS-MAPK cascade such as MEK remains a promising therapeutic strategy. The efficacy of trametinib (Tra), a small molecule inhibitor of MEK1/2 kinase activity, in combination with nab-paclitaxel-based chemotherapy was evaluated in preclinical models of PDAC. The addition of trametinib to chemotherapy regimens showed a trend for an additive effect on tumor growth inhibition in subcutaneous AsPC-1 and Panc-1 PDAC xenografts. In a peritoneal dissemination model, median animal survival compared to controls (20 days) was increased after therapy with NPT (33 days, a 65% increase), Tra (31 days, a 55% increase), NPT+Tra (37 days, a 85% increase), NPT+Gem (39 days, a 95% increase) and NPT+Gem+Tra (49 days, a 145% increase). Effects of therapy on intratumoral proliferation and apoptosis corresponded with tumor growth inhibition. Trametinib effects were specifically accompanied by a decrease in phospho-ERK and an increase in cleaved caspase-3 and cleaved PARP-1 proteins. These findings suggest that the effects of nab-paclitaxel-based chemotherapy can be enhanced through specific inhibition of MEK1/2 kinase activity, and supports the clinical application of trametinib in combination with standard nab-paclitaxel-based chemotherapy in PDAC patients.