MARCH6 promotes hepatocellular carcinoma development through up-regulation of ATF2.

BACKGROUND: Hepatocellular carcinoma (HCC) is a common cause of cancer mortality worldwide. Recent studies have shown that the polytopic enzyme membrane associated ring-CH-type finger 6 (MARCH6) participates in tumorigenesis, but its function in HCC development needs to be investigated. This study aimed to explore the role of MARCH6 in HCC. METHODS: Expression of MARCH6 in human HCC samples was checked by immunohistochemical staining assay. Clinical relevance of MARCH6 and activating transcription factor 2 (ATF2) was analyzed from TCGA database. CCK-8, EdU staining, colony formation and transwell were performed to assess cell proliferation, growth and migration. Xenografted tumorigenesis was used to examine in vivo role MARCH6. Immunoblotting was applied to detect protein abundance. RESULTS: We found that MARCH6 expression was elevated in human HCC samples. Over-expression of MARCH6 was associated with poor prognosis of HCC patients. Up-expression of MARCH6 promoted cell growth and migration of HCC cells. In contrast, the HCC cell growth and migration were suppressed by MARCH6 knockdown. Furthermore, the DNA synthesis was enhanced by MARCH6. The expression of ATF2 was potentiated by MARCH6 over-expression, while it was suppressed by MARCH6 silencing. TCGA database showed positive correlation between the expression of MARCH6 and ATF2. Importantly, ATF2 expression contributed to the oncogenic function of HCC cells. CONCLUSION: Our findings suggest that MARCH6-mediated ATF2 up-regulation contributes to HCC development. MARCH6 may be a promising target for the diagnosis and treatment of HCC.

mSigSDK - private, at scale, computation of mutation signatures.

In our previous work, we demonstrated that it is feasible to perform analysis on mutation signature data without the need for downloads or installations and analyze individual patient data at scale without compromising privacy. Building on this foundation, we developed an in-browser Software Development Kit (a JavaScript SDK), mSigSDK, to facilitate the orchestration of distributed data processing workflows and graphic visualization of mutational signature analysis results. We strictly adhered to modern web computing standards, particularly the modularization standards set by the ECMAScript ES6 framework (JavaScript modules). Our approach allows for the computation to be entirely performed by secure delegation to the computational resources of the user's own machine (in-browser), without any downloads or installations. The mSigSDK was developed primarily as a companion library to the mSig Portal resource of the National Cancer Institute Division of Cancer Epidemiology and Genetics (NIH/NCI/DCEG), with a focus on FAIR extensibility as components of other researchers' own data science constructs. Anticipated extensions include the programmatic operation of other mutation signature API ecosystems such as SIGNAL and COSMIC, advancing towards a data commons for mutational signature research (Grossman et al., 2016).

Low Dopamine D2 Receptor Expression Drives Gene Networks Related to GABA, cAMP, Growth and Neuroinflammation in Striatal Indirect Pathway Neurons.

Background: A salient effect of addictive drugs is to hijack the dopamine reward system, an evolutionarily conserved driver of goal-directed behavior and learning. Reduced dopamine type 2 receptor availability in the striatum is an important pathophysiological mechanism for addiction that is both consequential and causal for other molecular, cellular, and neuronal network differences etiologic for this disorder. Here, we sought to identify gene expression changes attributable to innate low expression of the Drd2 gene in the striatum and specific to striatal indirect medium spiny neurons (iMSNs). Methods: Cre-conditional, translating ribosome affinity purification (TRAP) was used to purify and analyze the translatome (ribosome-bound messenger RNA) of iMSNs from mice with low/heterozygous or wild-type Drd2 expression in iMSNs. Complementary electrophysiological recordings and gene expression analysis of postmortem brain tissue from human cocaine users were performed. Results: Innate low expression of Drd2 in iMSNs led to differential expression of genes involved in GABA (gamma-aminobutyric acid) and cAMP (cyclic adenosine monophosphate) signaling, neural growth, lipid metabolism, neural excitability, and inflammation. Creb1 was identified as a likely upstream regulator, among others. In human brain, expression of FXYD2, a modulatory subunit of the Na/K pump, was negatively correlated with DRD2 messenger RNA expression. In iMSN-TRAP-Drd2HET mice, increased Cartpt and reduced S100a10 (p11) expression recapitulated previous observations in cocaine paradigms. Electrophysiology experiments supported a higher GABA tone in iMSN-Drd2HET mice. Conclusions: This study provides strong molecular evidence that, in addiction, inhibition by the indirect pathway is constitutively enhanced through neural growth and increased GABA signaling.