Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:2.7.10.1 (
ERK
)
95,504
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The ability of human embryonic stem cells (ESCs) to unlimited proliferation and huge differentiation potential makes them very attractive tool both for basic research and biological medicine. There are still little known about mechanisms that govern their differentiation or keep them in a pluripotency state. A variety of signaling events determines gene expression profiles responsible for such mechanisms activation. Protein kinases are key components of the signaling cascades. The knowledge about protein kinases expression profile in undifferentiated ESCs and embryoid bodies (EBs) will allow to understand early differentiation events. We constructed cDNA libraries containing fragments of protein kinases catalytic domain that were expressed in undifferentiated cells or EB of hESM01, hESM02 cell lines. We detected high level of
MAK-V
expression using Northern-blot hybridization. Semi-quantitative RT-PCR was used to compare the level of abundantly expressed kinases
MAK-V
, A-RAF-1, MARK3,
IGF1R
, NEK3 and NEK7 in undifferentiated ESCs or derived EBs.
...
PMID:[Protein kinases abundantly expressed in undifferentiated human ESC lines and derived embryoid bodies]. 1791 40
Breast cancer patients who are
HER2
-positive receive targeted inhibitors to
HER2
, including trastuzumab and lapatinib. While patients benefit from the use of
HER2
inhibitors, many fail therapy and almost all patients become resistant to treatment, indicating a critical need to prevent treatment failure. Several recent studies indicate that activation of autophagy contributes to trastuzumab and lapatinib resistance and demonstrate that impairing autophagy in breast cancer cells is therapeutically beneficial. Moreover, autophagy is mechanistically linked through signaling crosstalk to apoptotic pathways, where activation of one process impacts the other. Therefore, understanding the molecular mechanisms that control these processes may uncover novel areas of therapeutic intervention to combat or prevent resistance in breast cancer. We previously characterized the protein kinase
HUNK
as a breast cancer-promoting factor in
HER2
/neu-induced mammary tumor models, in which
HUNK
supported the survival of
HER2
/neu-positive tumor cells, likely through the regulation of apoptosis. Because significant crosstalk exists between apoptotic and autophagy proteins, we now examine if
HUNK
is also able to regulate cell survival through modulation of autophagy using
HER2
inhibitor sensitive and resistant breast cancer models. Furthermore, we investigate whether inhibiting
HUNK
impairs in vivo tumor growth that is initiated by
HER2
inhibitor-resistant breast cancer cells. Our findings indicate that therapeutically targeting
HUNK
is a potential strategy for overcoming resistance and that resistant breast cancer cells maintain
HUNK
expression to drive tumorigenesis, an observation that is consistent with a pro-survival role for this kinase.
...
PMID:Regulation of cell survival by HUNK mediates breast cancer resistance to HER2 inhibitors. 2551 31
Strategies for successful primary treatment of
HER2
-positive breast cancer include use of the
HER2
inhibitors trastuzumab or lapatinib in combination with standard chemotherapy. While successful, many patients develop resistance to these
HER2
inhibitors indicating an unmet need. Consequently, current research efforts are geared toward understanding mechanisms of resistance and the signaling modalities that regulate these mechanisms. We have undertaken a study to examine whether signaling molecules downstream of epidermal growth factor receptor, which often act as compensatory signaling outlets to circumvent
HER2
inhibition, can be co-targeted to overcome resistance. We identified JNK signaling as a potential area of intervention and now show that inhibiting JNK using the pan-JNK inhibitor, SP600125, is effective in the
HER2
-positive, resistant JIMT-1 xenograft mammary tumor model. We also investigate potential combination strategies to bolster the effects of JNK inhibition and find that co-targeting of JNK and the protein kinase
HUNK
can prohibit tumor growth of resistant
HER2
-positive mammary tumors in vivo.
...
PMID:Co-Targeting of JNK and HUNK in Resistant HER2-Positive Breast Cancer. 2704 89
Lactotroph adenoma, also called prolactinoma, is the most common pituitary tumor but little is known about its pathogenesis. Mouse models of prolactinoma can be useful to better understand molecular mechanisms involved in abnormal lactotroph cell proliferation and secretion. We have previously developed a prolactin receptor deficient (
Prlr
-/-
) mouse, which develops prolactinoma. The present study aims to explore the natural history of prolactinoma formation in
Prlr
-/-
mice, using hormonal, radiological, histological and molecular analyses to uncover mechanisms involved in lactotroph adenoma development.
Prlr
-/-
females develop large secreting prolactinomas from 12 months of age, with a penetrance of 100%, mimicking human aggressive densely granulated macroprolactinoma, which is a highly secreting subtype. Mean blood PRL measurements reach 14 902 ng/mL at 24 months in
Prlr
-/-
females while PRL levels were below 15 ng/mL in control mice (
p
< 0.01). By comparing pituitary microarray data of
Prlr
-/-
mice and an estrogen-induced prolactinoma model in ACI rats, we pinpointed 218 concordantly differentially expressed (DE) genes involved in cell cycle, mitosis, cell adhesion molecules, dopaminergic synapse and estrogen signaling. Pathway/gene-set enrichment analyses suggest that the transcriptomic dysregulation in both models of prolactinoma might be mediated by a limited set of transcription factors (i.e., STAT5, STAT3, AhR, ESR1, BRD4, CEBPD, YAP, FOXO1) and kinases (i.e., JAK2, AKT1, BRAF, BMPR1A, CDK8,
HUNK
,
ALK
,
FGFR1
, ILK). Our experimental results and their bioinformatic analysis provide insights into early genomic changes in murine models of the most frequent human pituitary tumor.
...
PMID:Natural and molecular history of prolactinoma: insights from a
Prlr
-/-
mouse model. 2946 61
HUNK
is a protein kinase that is implicated in
HER2
-positive (HER2+) breast cancer progression and resistance to
HER2
inhibitors. Though prior studies suggest there is therapeutic potential for targeting
HUNK
in HER2+ breast cancer, pharmacological agents that target
HUNK
are yet to be identified. A recent study showed that the broad-spectrum kinase inhibitor staurosporine binds to the
HUNK
catalytic domain, but the effect of staurosporine on
HUNK
enzymatic activity was not tested. We now show that staurosporine inhibits the kinase activity of a full length
HUNK
protein. Our findings further suggest that inhibiting
HUNK
with staurosporine has a strong effect on suppressing cell viability of
HER2
/neu mammary and breast cancer cells, which express high levels of
HUNK
protein and are dependent on
HUNK
for survival. Significantly, we use
in vitro
and
in vivo
methods to show that staurosporine synergizes with the
HER2
inhibitor lapatinib to restore sensitivity toward
HER2
inhibition in a
HER2
inhibitor resistant breast cancer model. Collectively, these studies indicate that pharmacological inhibition of
HUNK
kinase activity has therapeutic potential for HER2+ breast cancers, including HER2+ breast cancers that have developed drug resistance.
...
PMID:Staurosporine, an inhibitor of hormonally up-regulated neu-associated kinase. 3054 10