Purpose: To determine the incidence of Xp11 translocation renal cell carcinoma (RCC) in adult patients using cytogenetics and immunohistochemstry. Experimental Design: Cytogenetic studies were prospectively done using tumor samples from 443 consecutive adult Japanese patients (ages 15-89 years) who underwent nephrectomy for RCC. TFE3 immunohistochemistry was done for cases in which cytogenetic results were not obtained. Clinicopathologic characteristics of Xp11 translocation RCC were examined. Results: Mitotic cells suitable for cytogenetic analysis were obtained in 244 tumor samples (55%); among these, we identified 4 cases (1.6%) of Xp11 translocation RCC. TFE3 immunohistochemistry identified 3 positive cases (1.5%) among the remaining 199 cases. The median age of the 7 patients was 41 years (range, 15-59 years), and 15% of RCC patients (4 of 26) who were younger than ages 45 years had this type of RCC. Of the four Xp11 translocation RCC patients whose karyotypes were determined, two had an ASPL-TFE3 gene fusion. Of these 2, 1 had pulmonary metastasis at presentation, and the other developed liver metastasis 12 months after nephrectomy and died of the disease. The remaining two patients had PRCC-TFE3 and PSF-TFE3 gene fusions, respectively. Both had nodal involvement but remained disease free for 3 and 5 years, respectively, after surgical resection of lymph node metastases. Of the 3 immunohistochemically diagnosed patients, 1 had nodal metastases at presentation and died 9 months after surgery. Conclusions: This is the first report to determine the incidence of Xp11 translocation RCC in adult patients. We found that this disease is relatively common in young adults.

Dysregulation of the G₁/S transition in the cell cycle contributes to tumor development. The oncogenic transcription factors c-Jun and c-Myc are indispensable regulators at this transition, and their aberrant expression is associated with many malignancies. Degradation of c-Jun/c-Myc is a critical process for the G₁/S transition, which is initiated upon phosphorylation by glycogen synthase kinase 3 β (GSK3β). However, a specific kinase or kinases responsible for priming phosphorylation events that precede this GSK3β modification has not been definitively identified. Here, we found that the dual-specificity tyrosine phosphorylation–regulated kinase DYRK2 functions as a priming kinase of c-Jun and c-Myc. Knockdown of DYRK2 in human cancer cells shortened the G₁ phase and accelerated cell proliferation due to escape of c-Jun and c-Myc from ubiquitination-mediated degradation. In concert with these results, silencing DYRK2 increased cell proliferation in human cancer cells, and this promotion was completely impeded by codeprivation of c-Jun or c-Myc in vivo. We also found marked attenuation of DYRK2 expression in multiple human tumor samples. Downregulation of DYRK2 correlated with high levels of unphosphorylated c-Jun and c-Myc and, importantly, with invasiveness of human breast cancers. These results reveal that DYRK2 regulates tumor progression through modulation of c-Jun and c-Myc.

Summary: Stress and low socioeconomic status in humans confer increased vulnerability to morbidity and mortality. However, this association is not mechanistically understood nor has its causation been explored in animal models thus far. Recently, cellular senescence has been suggested as a potential mechanism linking lifelong stress to age‐related diseases and shorter life expectancy in humans. Here, we established a causal role for lifelong social stress on shortening lifespan and increasing the risk of cardiovascular disease in mice. Specifically, we developed a lifelong chronic psychosocial stress model in which male mouse aggressive behavior is used to study the impact of negative social confrontations on healthspan and lifespan. C57BL/6J mice identified through unbiased cluster analysis for receiving high while exhibiting low aggression, or identified as subordinate based on an ethologic criterion, had lower median and maximal lifespan, and developed earlier onset of several organ pathologies in the presence of a cellular senescence signature. Critically, subordinate mice developed spontaneous early‐stage atherosclerotic lesions of the aortic sinuses characterized by significant immune cells infiltration and sporadic rupture and calcification, none of which was found in dominant subjects. In conclusion, we present here the first rodent model to study and mechanistically dissect the impact of chronic stress on lifespan and disease of aging. These data highlight a conserved role for social stress and low social status on shortening lifespan and increasing the risk of cardiovascular disease in mammals and identify a potential mechanistic link for this complex phenomenon.

Multidrug‐resistant (MDR) multiple myeloma (MM) patients who fail chemotherapy frequently express MDR1 protein, which serves as an efflux pump that protects neoplastic cells. The expression of lung resistance protein (LRP), which mediates intercellular and nucleocytoplasmic transport, is also correlated with chemotherapy resistance and shorter survival of MM patients. Here, we investigated the chemotherapy‐induced change of MDR expression in MM patients using quantitative RT‐PCR. Overall expression levels of MDR1 and LRP in MM patients were significantly higher than those in control subjects and increased after chemotherapy. More than half of the patients exhibited increased expression of MDR1 (14/26) or LRP (17/26) after chemotherapy. Also, the expression of inhibitor of apoptosis proteins (IAP) was determined in association with the prognosis of the patients. Among patients with increased MDR1‐expression after chemotherapy, those with a poor outcome exhibited significant increases in survivin, cIAP1, cIAP2, and XIAP expression by chemotherapy compared with those with a good prognosis. Similarly, in the LRP expression‐increased group, patients with a poor outcome showed significant increases of cIAP1 and cIAP2 expression compared with those with longer survival. In patients with reduced‐MDR1 or LRP expression after chemotherapy, changes in the expression of IAPs induced by chemotherapy did not correlate with their prognosis. These findings indicate that IAP family proteins might play a role in worsening the prognosis of MM patients in association with chemotherapy‐induced overexpression of MDR1 or LRP. Am. J. Hematol., 2006.