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Summary: The TMEM127 gene encodes a transmembrane protein of poorly known function that is mutated in pheochromocytomas, neural crest-derived tumors of adrenomedullary cells. Here, we report that, at single-nucleus resolution, TMEM127-mutant tumors share precursor cells and transcription regulatory elements with pheochromocytomas carrying mutations of the tyrosine kinase receptor RET. Additionally, TMEM127-mutant pheochromocytomas, human cells, and mouse knockout models of TMEM127 accumulate RET and increase its signaling. TMEM127 contributes to RET cellular positioning, trafficking, and lysosome-mediated degradation. Mechanistically, TMEM127 binds to RET and recruits the NEDD4 E3 ubiquitin ligase for RET ubiquitination and degradation via TMEM127 C-terminal PxxY motifs. Lastly, increased cell proliferation and tumor burden after TMEM127 loss can be reversed by selective RET inhibitors in vitro and in vivo. Our results define TMEM127 as a component of the ubiquitin system and identify aberrant RET stabilization as a likely mechanism through which TMEM127 loss-of-function mutations cause pheochromocytoma.

TMEM127 is a tumor suppressor protein, loss of which predisposes to catecholamine-secreting tumors. Here the authors show that TMEM127 expression is modulated by nutritional status and that it has a role in regulating organismal insulin sensitivity.

OBJECTIVE: The aim of this study is to compare surgery with adjuvant chemoradiotherapy versus non-surgical treatments for patients with early-stage small cell lung cancer (SCLC) based on the short-term and long-term efficacy. METHODS: SCLC patients who underwent a pulmonary lobectomy with post-surgical radiotherapy or chemotherapy were assigned to the surgical group. SCLC patients who received radiotherapy or chemotherapy alone were classified into the nonsurgical group. The clinical efficacy was evaluated as complete remission (CR), partial remission (PR), stable disease (SD), or progressive disease (PD). The total effectiveness rate was calculated as CR + PR. The 1-, 3-, and 5-year survival rates of the two groups were compared. RESULTS: Compared with the non-surgical group, the CR rate and the total effectiveness rate were higher in the surgical group, and the total effectiveness rate for male patients and patients without a smoking history were also higher in the surgical group. Distant metastasis and local recurrence concurrent with distant metastasis in the surgical group were both lower in the surgical group than in the non-surgical group. Compared with the non-surgical group, the local recurrence in male patients was lower in the surgical group, and patients in the surgical group had lower distant metastasis at TNM stage IIb. The 1-, 3-, and 5-year survival rates were higher in the surgical group than in the non-surgical group. CONCLUSIONS: These findings indicate that for patients with early-stage SCLC, better scores in effectiveness rate, disease progression, and 1-, 3-, and 5-year survival rates were observed in patients who underwent surgery followed by adjuvant chemoradiotherapy when compared with patients without surgical treatment. [ABSTRACT FROM AUTHOR]