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Background Progesterone Receptor Membrane Component 1 (PGRMC1) is expressed in many cancer cells, where it is associated with detrimental patient outcomes. It contains phosphorylated tyrosines which evolutionarily preceded deuterostome gastrulation and tissue differentiation mechanisms. Results We demonstrate that manipulating PGRMC1 phosphorylation status in MIA PaCa-2 (MP) cells imposes broad pleiotropic effects. Relative to parental cells over-expressing hemagglutinin-tagged wild-type (WT) PGRMC1-HA, cells expressing a PGRMC1-HA-S57A/S181A double mutant (DM) exhibited reduced levels of proteins involved in energy metabolism and mitochondrial function, and altered glucose metabolism suggesting modulation of the Warburg effect. This was associated with increased PI3K/AKT activity, altered cell shape, actin cytoskeleton, motility, and mitochondrial properties. An S57A/Y180F/S181A triple mutant (TM) indicated the involvement of Y180 in PI3K/AKT activation. Mutation of Y180F strongly attenuated subcutaneous xenograft tumor growth in NOD-SCID gamma mice. Elsewhere we demonstrate altered metabolism, mutation incidence, and epigenetic status in these cells. Conclusions Altogether, these results indicate that mutational manipulation of PGRMC1 phosphorylation status exerts broad pleiotropic effects relevant to cancer and other cell biology.

Alzheimer&rsquo, s disease (AD) is a progressive neurodegenerative disorder with an unclear cause. It appears that multiple factors participate in the process of neuronal damage including oxidative stress and accumulation of the protein amyloid &beta, (A&beta, ) in the brain. The search for a treatment for this disorder is essential as current medications are limited to alleviating symptoms and palliative effects. The aim of this study is to investigate the effects of mint extracts on selected mechanisms implicated in the development of AD. To enable a thorough investigation of mechanisms, including effects on &beta, secretase (the enzyme that leads to the formation of A&beta, ), on A&beta, aggregation, and on oxidative stress and apoptosis pathways, a neuronal cell model, SH-SY5Y cells, was selected. Six Mentha taxa were investigated for their in vitro &beta, secretase (BACE) and A&beta, aggregation inhibition activities. Moreover, their neuroprotective effects on H2O2-induced oxidative stress and apoptosis in SH-SY5Y cells were evaluated through caspase activity. Real-time PCR and Western blot analysis were carried out for the two most promising extracts to determine their effects on signalling pathways in SH-SY5Y cells. All mint extracts had strong BACE inhibition activity. M. requienii extracts showed excellent inhibition of A&beta, aggregation, while other extracts showed moderate inhibition. M. diemenica and M. requienii extracts lowered caspase activity. Exposure of SH-SY5Y cells to M. diemenica extracts resulted in a decrease in the expression of pro-apoptotic protein, Bax, and an elevation in the anti-apoptotic protein, Bcl-xL, potentially mediated by down-regulation of the ASK1-JNK pathway. These results indicate that mint extracts could prevent the formation of A&beta, and also could prevent their aggregation if they had already formed. M. diemenica and M. requienii extracts have potential to suppress apoptosis at the cellular level. Hence, mint extracts could provide a source of efficacious compounds for a therapeutic approach for AD.

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder that develops as a consequence of different factors such as oxidative stress and accumulation of the protein amyloid β (Aβ) in the brain, resulting in apoptosis of neuronal cells. The search for a treatment for this disorder is essential as current medications are limited to alleviating symptoms and palliative effects. The aim of this study is to investigate the effects of mint extracts on selected mechanisms implicated in the development of AD. To enable a thorough investigation of mechanisms, including effects on -secretase (the enzyme the leads to the formation of A), on Aβ aggregation, and on oxidative stress and apoptosis pathways, a neuronal cell model, SH-SY5Y cells was selected. Six Mentha taxa were investigated for their in vitro β-secretase (BACE) and Aβ-aggregation inhibition activities. Also, their neuroprotective effects on H2O2-induced oxidative stress and apoptosis in SH-SY5Y cells were evaluated through caspase activity. Real-time PCR and Western blot analysis were carried out for the two most promising extracts to determine their effects on signalling pathways in SH-SY5Y cells. All mint extracts had strong BACE inhibition activity. M. requienii extracts showed excellent inhibition of Aβ-aggregation, while other extracts showed moderate inhibition. M. diemenica and M. requienii extracts lowered caspase activity. Exposure of SH-SY5Y cells to M. diemenica extracts resulted in a decrease in the expression of pro-apoptotic protein, Bax, and an elevation in the anti-apoptotic protein, Bcl-xL, potentially mediated by down-regulation of ASK1-JNK pathway. These results indicate that mint extracts could prevent the formation of Aβ and also could prevent their aggregation if they had already formed. M. diemenica and M. requienii extracts have potential to suppress apoptosis at the cellular level. Hence, mint extracts could provide a source of efficacious compounds for a therapeutic approach for AD.

Background Progesterone receptor membrane component 1 (PGRMC1) is often elevated in cancers, and exists in alternative states of phosphorylation. A motif centered on PGRMC1 Y180 was evolutionarily acquired concurrently with the embryological gastrulation organizer that orchestrates vertebrate tissue differentiation. Results Here, we show that mutagenic manipulation of PGRMC1 phosphorylation alters cell metabolism, genomic stability, and CpG methylation. Each of several mutants elicited distinct patterns of genomic CpG methylation. Mutation of S57A/Y180/S181A led to increased net hypermethylation, reminiscent of embryonic stem cells. Pathways enrichment analysis suggested modulation of processes related to animal cell differentiation status and tissue identity, as well as cell cycle control and ATM/ATR DNA damage repair regulation. We detected different genomic mutation rates in culture. Conclusions A companion manuscript shows that these cell states dramatically affect protein abundances, cell and mitochondrial morphology, and glycolytic metabolism. We propose that PGRMC1 phosphorylation status modulates cellular plasticity mechanisms relevant to early embryological tissue differentiation.

PGRMC1 is a protein from the MAPR family with a range of cellular functions. PGRMC1 has been described to play a role in fertility, neuroprotection, steroidogenesis, membrane trafficking and in cancer cell biology. PGRMC1 represents a likely key regulator of cell metabolism and proliferation, as well as a potential target for anti-cancer therapies. To further understand the functions of PGRMC1 and the mechanism of the small molecule inhibitor of PGRMC1, AG-205, proteins differentially bound to PGRMC1 were identified following AG-205 treatment of MIA PaCa-2 cells. Our results suggest that AG-205 influences PGRMC1 interactions with the actin cytoskeleton. The binding of two PGRMC1-associated proteins that support this, RACK1 and alpha-Actinin-1, was reduced following AG-205 treatment. The biology associated with PGRMC1 binding partners identified here merits further investigation.

Background: Progesterone Receptor Membrane Component 1 (PGRMC1) is expressed in many cancer cells, where it is associated with detrimental patient outcomes. Multiple different functions and cellular locations have been attributed to PGRMC1 in a variety of contexts, however the mechanisms underlying PGRMC1 biology remain obscure. The protein contains several phosphorylated residues including tyrosines which were acquired in animal evolution prior to bilateral symmetry, and could be involved with animal cell differentiation mechanisms. Results: Here we demonstrate that mutagenic manipulation of PGRMC1 phosphorylation status in MIA PaCa-2 pancreatic cells exerts broad pleiotropic effects, influencing cell plasticity and tumorigenicity, as assayed by cell biological and proteomics measurements. Relative to parental cells over-expressing hemagglutinin-tagged wild-type PGRMC1-HA, cells expressing a PGRMC1-HA-S57A/S181A double mutant exhibited reduced levels of proteins involved in energy metabolism and mitochondrial function, and altered glucose metabolism suggesting modulation of the Warburg effect. This was associated with Rho-kinase inhibitor-sensitive changes including altered cell shape, motility, increased PI3K/Akt activity, and fragmented mitochondrial morphology. An S57A/Y180F/S181A triple mutant reduced PI3K/Akt activity, indicating involvement of Y180 in PI3K/Akt induction. Both triple mutant and Y180F single mutant cells exhibited attenuated mouse xenograft tumor growth. Conclusions: Phosphorylation status of the PGRMC1 tyrosine 180 regulatory motif exerts dramatic influence over cancer cell biology, including Warburg effect-like glucose metabolism. In accompanying papers we show that: 1) the cells examined here exhibit dramatically altered metabolism and epigenetic status, with the triple mutant inducing hypermethylation similar to that of embryonic stem cells, and that 2) Y180 was acquired in evolution concurrently with appearance of the organizer that induces animal gastrulation. Taken together, these results indicate that the undescribed mechanisms regulating PGRMC1 phosphorylation may be of great disease relevance and merit urgent investigation.