Ampullary cancer: Evaluation of somatic and germline genetic alterations and association with clinical outcomes
CANCER
Authors: Wong, Winston; Lowery, Maeve A.; Berger, Michael F.; Kemel, Yelena; Taylor, Barry; Zehir, Ahmet; Srinivasan, Preethi; Bandlamudi, Chaitanya; Chou, Joanne; Capanu, Marinela; Varghese, Anna; Yu, Kenneth H.; Iacobuzio-Donahue, Christine A.; Shia, Jinru; Klimstra, David S.; Jarnagin, William R.; Stadler, Zsofia K.; O'Reilly, Eileen M.
Abstract
Background Ampullary carcinoma (AC) is a rare gastrointestinal cancer. Pathogenic germline alterations (PGAs) in BRCA2 and potentially targetable somatic alterations (SAs) in ERBB2 and ELF3 have been previously described in AC. Memorial Sloan Kettering Cancer Center has implemented an opt-in strategy for germline testing (GT) and somatic testing (ST) for patients with AC to further evaluate the spectrum of PGAs and SAs. Methods Forty-five patients with pathologically confirmed AC prospectively consented with the Memorial Sloan Kettering Integrated Mutation Profiling of Actionable Cancer Targets (MSK-IMPACT) test (410-468 genes). A subset of the cohort (23 of the 45 patients) also consented to GT with MSK-IMPACT (76-88 genes). Germline data for 21 of the remaining 22 patients who had not consented to GT were obtained in a de-identified fashion without clinical correlation. Clinicopathologic features, treatment histories, and survival data for consenting patients were collected and analyzed. Results Pancreaticobiliary, intestinal, and mixed features of the 2 types were the primary pathologic subtypes of AC identified in this cohort. No difference in median overall survival was found between pathologic subtypes. Eight of 44 patients (18%) were identified as harboring pathogenic mutations in BRCA2, ATM, RAD50, and MUTYH. In addition, this study found a wide spectrum of SAs in genes such as KRAS, MDM2, ERBB2, ELF3, and PIK3CA. Two patients in the cohort underwent SA-targeted therapy, and 1 had a partial radiographic response. Conclusions Mutations in multiple somatic and germline genes were identified in this cohort. Significantly, actionable targets were identified in the tumors, and broader testing for PGAs and SAs should be considered for all patients with AC.
A prion-like domain in ELF3 functions as a thermosensor inArabidopsis
NATURE
Authors: Jung, Jae-Hoon; Barbosa, Antonio D.; Hutin, Stephanie; Kumita, Janet R.; Gao, Mingjun; Derwort, Dorothee; Silva, Catarina S.; Lai, Xuelei; Pierre, Elodie; Geng, Feng; Kim, Sol-Bi; Baek, Sujeong; Zubieta, Chloe; Jaeger, Katja E.; Wigge, Philip A.
Abstract
The adaptability of the plantArabidopsis thalianato different temperatures is regulated by the ability of its ELF3 protein to undergo liquid-liquid phase separation, in a manner that is dependent on the protein's prion-like domain. Temperature controls plant growth and development, and climate change has already altered the phenology of wild plants and crops(1). However, the mechanisms by which plants sense temperature are not well understood. The evening complex is a major signalling hub and a core component of the plant circadian clock(2,3). The evening complex acts as a temperature-responsive transcriptional repressor, providing rhythmicity and temperature responsiveness to growth through unknown mechanisms(2,4-6). The evening complex consists of EARLY FLOWERING 3 (ELF3)(4,7), a large scaffold protein and key component of temperature sensing; ELF4, a small alpha-helical protein; and LUX ARRYTHMO (LUX), a DNA-binding protein required to recruit the evening complex to transcriptional targets. ELF3 contains a polyglutamine (polyQ) repeat(8-10), embedded within a predicted prion domain (PrD). Here we find that the length of the polyQ repeat correlates with thermal responsiveness. We show that ELF3 proteins in plants from hotter climates, with no detectable PrD, are active at high temperatures, and lack thermal responsiveness. The temperature sensitivity of ELF3 is also modulated by the levels of ELF4, indicating that ELF4 can stabilize the function of ELF3. In bothArabidopsisand a heterologous system, ELF3 fused with green fluorescent protein forms speckles within minutes in response to higher temperatures, in a PrD-dependent manner. A purified fragment encompassing the ELF3 PrD reversibly forms liquid droplets in response to increasing temperatures in vitro, indicating that these properties reflect a direct biophysical response conferred by the PrD. The ability of temperature to rapidly shift ELF3 between active and inactive states via phase transition represents a previously unknown thermosensory mechanism.