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Background Disabled-2 (Dab2) is known as a tumor suppressor as well as a Wnt pathway inhibitor. We previously reported that Dab2 was down-regulated due to gene promoter hypermethylation in lung cancer. Here, we aim to study if X-ray irradiation can induce de-methylation of the Dab2 gene and subsequently up-regulate its expression, and also to attempt to suppress the malignant biological behavior of and enhance the radiosensitivity in lung cancer cells with hypermethylation of the Dab2 gene. Methods Immunostaining was performed to investigate the relationship between Dab2 expression and lung cancer clinicopathological characteristics. Bisulfite sequencing PCR (BSP) was used to evaluate the methylation status of lung cancer cells with or without X-ray treatment. Real-time PCR and western Blot were performed to investigate the expression of Dab2, Wnt pathway factors, DNMTs and methyl CpG binding protein 2 (MeCP2). Colony Formation, matrigel invasion and xenograft experiment were performed to evaluate the malignant biological behavior of lung cancer cells with irradiation. Results The result of immunostaining of Dab2 in lung cancer tissues showed that decreased Dab2 expression was positively correlated with poor differentiation, lymph node metastasis, advanced TNM stage and poor prognosis. X-ray treatment significantly up-regulated Dab2 expression and inhibited Wnt factors in LK2 cells (with hypermethylation of the Dab2 gene promoter, P

Pleuropulmonary blastomas (PPB) are rare aggressive paediatric lung malignancies associated withDICER1variants. We present two cases, a 2-year-old girl with upper respiratory tract symptoms as well as a 6-month-old girl sibling undergoing screening due to family history of malignancy. Imaging of the 2-year-old girl revealed a large mass filling the right hemithorax which was determined to be a type II PPB after pathological examination. Imaging of the 6-month-old sibling demonstrated a small cystic lesion in the posterior basal segment of the right lower lobe which was determined to be a type 1r PPB after pathological examination. The 2-year-old girl received adjuvant chemotherapy while the baby sister underwent resection alone and both are alive and well at 12 months and 7 months, respectively. Sequence analysis in both cases confirmed the sameDICER1variation, c.2437-2A>G (likely pathogenic), which has not been previously described in the literature.

Rationale Signet-ring cell is a rare morphological finding in bone marrow, which usually indicates metastatic carcinoma from either the gastrointestinal tract or a primary hematolymphoid neoplasm. Here, we present a very unusual case of lobular breast carcinoma with metastasis to the bone marrow. Patient concerns A 67-year-old female with estrogen receptor (ER)-positive lobular breast carcinoma was staged as T3N3M0, and treated with modified radical mastectomy followed by chemotherapy and radiotherapy. One year after treatment, she was noted to have moderate thrombocytopenia on complete blood count with the remainder of the parameters within normal limits. Radiographic examination revealed no evidence of recurrent disease. Diagnosis Bone marrow biopsy was performed to exclude therapy-related myelodysplastic syndrome (MDS), which demonstrated hypercellularity with "hyperplastic" hematopoiesis. Upon closer inspection, a few signet-ring cells were identified which morphologically resembled histiocytes. These formed an interstitial infiltrate among the predominantly hematopoietic elements, and could have been easily overlooked. Immunohistochemistry demonstrated that these signet-ring cells were positive for pancytokeratin as well as ER which confirmed metastatic lobular breast carcinoma. On retrospective review of the aspirate smear, rare signet-ring cells were identified. Interventions The patient was treated with additional chemotherapy. Outcomes The patient eventually succumbed to overt dissemination after 14 months. Lessons Due to the relative discohesiveness of lobular breast carcinoma, the cells frequently assume single-cell infiltration in bone marrow. This attribute, along with small cell size, bland cytologic features and paucity of tissue response, contributes to its escaping from identification on hematoxylin-eosin (H&E) sections. In this case, the signet-ring cells were hidden in apparently hyperplastic hematopoiesis. Careful inspection raised the possibility of occult metastasis which was readily detected and confirmed with immunohistochemistry.

The heat shock response (HSR) is responsible for maintaining cellular and organismal health through the regulation of proteostasis. Recent data demonstrating that the mammalian HSR is regulated by SIRT1 suggest that this response may be under metabolic control. To test this hypothesis, we have determined the effect of caloric restriction in Caenorhabditis elegans on activation of the HSR and have found a synergistic effect on the induction of hsp70 gene expression. The homolog of mammalian SIRT1 in C. elegans is Sir2.1. Using a mutated C. elegans strain with a sir2.1 deletion, we show that heat shock and caloric restriction cooperate to promote increased survivability and fitness in a sir2.1-dependent manner. Finally, we show that caloric restriction increases the ability of heat shock to preserve movement in a polyglutamine toxicity neurodegenerative disease model and that this effect is dependent on sir2.1.