Impact of Toll-like Receptor 4 Expression on Inflammatory Responses Related to Premature Membrane Rupture Induced by Lipopolysaccharide.

OBJECTIVE: This study aimed to determine the mechanism through which the expression of Toll-like receptor 4 (TLR4) influences the lipopolysaccharide (LPS)-induced inflammatory response, a condition that is associated with premature rupture of membranes (PROM). METHODS: Human myeloid leukemia mononuclear cells (THP-1) were employed as the experimental model. These cells were treated with LPS and the TLR4 inhibitor CLI-095 and subsequently divided into three groups. A range of assays were utilized, including methyl thiazolyl tetrazole (MTT) assay, real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) for measuring TLR4 and tumor necrosis factor α (TNF-α) mRNA levels, double antibody sandwich enzyme-linked immunosorbent assay (ELISA) for assessing monocyte chemoattractant protein 1 (MCP-1) and matrix metalloproteinase 9 (MMP-9), as well as secretion levels of interleukin (IL)-6 and IL-1ß. And western blotting was used to detect the expression of extracellular signal-regulated kinase (ERK) and nuclear factor κB (NF-κB) p65, which are components of the TLR4 downstream signaling pathway. RESULTS: The LPS-induced proliferation of THP-1 cells was significantly inhibited (p < 0.05) when compared with normal THP-1 cells. Moreover, LPS also promoted TLR4 mRNA and protein expression levels, TNF-α mRNA expression, secretion of inflammatory factors, and phosphorylation of ERK and NF-κB p65 proteins (p < 0.05). On the other hand, administration of the TLR4 inhibitor CLI-095 significantly inhibited the expression of TLR4 mRNA and protein. It also effectively increased the proliferative activity of THP-1 cells and inhibited the secretion of TNF-α and inflammatory factors, as well as the phosphorylation of ERK and NF-κB p65 proteins (p < 0.05). CONCLUSIONS: In summary, suppressing TLR4 expression can mitigate inflammatory responses, thereby reducing the likelihood of premature rupture of membranes during pregnancy, which is often triggered by such inflammation.

Erratum: Estrogen receptor α/prolactin receptor bilateral crosstalk promotes bromocriptine resistance in prolactinomas: Erratum.

[This corrects the article DOI: 10.7150/ijms.51176.].

GASC1 promotes glioma progression by enhancing NOTCH1 signaling.

Recent studies have reported that gene amplified in squamous cell carcinoma 1 (GASC1) is involved in the progression of several types of cancer. However, whether GASC1 promotes glioma progression remains unknown. Therefore, the present study aimed to investigate the effect of GASC1 exposure on glioma tumorigenesis. The western blot demonstrated that grade III and IV glioma tissues exhibited a higher mRNA and protein expression of GASC1. Moreover, CD133+ U87 or U251 cells from magnetic cell separation exhibited a higher GASC1 expression. Invasion Transwell assay, clonogenic assay and wound healing assay have shown that GASC1 inhibition using a pharmacological inhibitor and specific short hairpin (sh)RNA suppressed the invasive, migratory and tumorsphere forming abilities of primary culture human glioma cells. Furthermore, GASC1­knockdown decreased notch receptor (Notch) responsive protein hes family bHLH transcription factor 1 (Hes1) signaling. GASC1 inhibition reduced notch receptor 1 (NOTCH1) expression, and a NOTCH1 inhibitor enhanced the effects of GASC1 inhibition on the CD133+ U87 or U251 cell tumorsphere forming ability, while NOTCH1 overexpression abrogated these effects. In addition, the GASC1 inhibitor caffeic acid and/or the NOTCH1 inhibitor DAPT (a γ­Secretase Inhibitor), efficiently suppressed the human glioma xenograft tumors. Thus, the present results demonstrated the importance of GASC1 in the progression of glioma and identified that GASC1 promotes glioma progression, at least in part, by enhancing NOTCH signaling, suggesting that GASC1/NOTCH1 signaling may be a potential therapeutic target for glioma treatment.

Pimozide augments bromocriptine lethality in prolactinoma cells and in a xenograft model via the STAT5/cyclin D1 and STAT5/Bcl­xL signaling pathways.

As hyperprolactinemia is observed in patients with bromocriptine­resistant prolactinoma, prolactin (PRL) has been implicated in the development of bromocriptine resistance. Since PRL primarily mediates cell survival and drug resistance via the Janus kinase­2 (JAK2)/signal transducer and activator of transcription 5A (STAT5) signaling pathway, the STAT5 inhibitor, pimozide, may inhibit cell proliferation and reverse bromocriptine resistance in prolactinoma cells. In the present study, compared with bromocriptine or pimozide alone, the combination of pimozide and bromocriptine exerted enhanced reduction in cell growth and proliferation, and increased apoptosis and cell cycle arrest in bromocriptine­resistant prolactinoma cells. A reduction in phospho­STAT5, cyclin D1 and B­cell lymphoma extra­large (Bcl­xL) expression levels were observed in cells treated with the combination of drugs. In addition, pimozide suppressed spheroid formation of human pituitary adenoma stem­like cells, and reduced the protein expression of the cancer stem cell markers, CD133 and nestin. Pimozide did not exert any additional antitumor activity in STAT5­knockdown primary culture cells of human bromocriptine­resistant prolactinomas. Furthermore, Pimozide combined with bromocriptine treatment significantly reduced human prolactinoma xenograft growth. Western blot and immunohistochemical analyses also demonstrated significant inhibition of cell proliferation and stem cell marker proteins in vivo. Collectively, these data indicated that pimozide treatment reduced prolactinoma growth by targeting both proliferating cells and stem cells, at least in part, by inhibiting the STAT5/Bcl­xL and STAT5/cyclin D1 signaling pathways.

Estrogen receptor α/prolactin receptor bilateral crosstalk promotes bromocriptine resistance in prolactinomas.

Prolactinomas are the most common type of functional pituitary adenoma. Although bromocriptine is the preferred first line treatment for prolactinoma, resistance frequently occurs, posing a prominent clinical challenge. Both the prolactin receptor (PRLR) and estrogen receptor α (ERα) serve critical roles in the development and progression of prolactinomas, and whether this interaction between PRLR and ERα contributes to bromocriptine resistance remains to be clarified. In the present study, increased levels of ERα and PRLR protein expression were detected in bromocriptine-resistant prolactinomas and MMQ cells. Prolactin (PRL) and estradiol (E2) were found to exert synergistic effects on prolactinoma cell proliferation. Furthermore, PRL induced the phosphorylation of ERα via the JAK2-PI3K/Akt-MEK/ERK pathway, while estrogen promoted PRLR upregulation via pERα. ERα inhibition abolished E2-induced PRLR upregulation and PRL-induced ERα phosphorylation, and fulvestrant, an ERα inhibitor, restored pituitary adenoma cell sensitivity to bromocriptine by activating JNK-MEK/ERK-p38 MAPK signaling and cyclin D1 downregulation. Collectively, these data suggest that the interaction between the estrogen/ERα and PRL/PRLR pathways may contribute to bromocriptine resistance, and therefore, that combination treatment with fulvestrant and bromocriptine (as opposed to either drug alone) may exert potent antitumor effects on bromocriptine-resistant prolactinomas.

Ovarian granulocytic sarcoma as the primary manifestation of acute myelogenous leukemia.

Granulocytic sarcoma (GS) usually occurs concomitantly with or after the onset of acute myeloid leukemia (AML) or other myeloproliferative disorders, however, GS of the ovary as the primary manifestation of AML is exceedingly rare. To the best of our knowledge, eight cases of ovarian GS as the first sign of AML have been reported in the literature. Here, we report the ninth case: a 27-year-old female who presented with an ovarian mass without any underlying hematologic disorder. A high index of suspicion aided by immunohistochemistry established the correct diagnosis of undifferentiated GS that involved the ovary. Simultaneously, laboratory findings indicated that the blood counts continually increased after surgery. Five days after the surgery, bone marrow biopsy confirmed the presence of AML. After establishing the diagnosis, the patient was sent to the hematology department to receive cytosine arabinoside and idarubicin chemotherapy. This report outlines an exceedingly rare case of AML that initially manifested as an ovarian GS. Awareness of this entity will enable earlier diagnosis and appropriate treatment.

Synchronous poorly-differentiated neuroendocrine carcinoma and gastrointestinal stromal tumor of the stomach: a case report with immunohistochemical and molecular genetic analyses of KIT and PDGFRA.

Although the stomach is the most common location for gastrointestinal stromal tumor (GIST) with co-primary tumors, the synchronous appearance of a poorly differentiated neuroendocrine carcinoma (NEC) and GIST in the stomach is extremely rare. To the best of our knowledge, this is the first case of gastric GIST coexisting with gastric NEC to be reported in the literature. The current study reports the case of a 71-year-old male with gastric poorly differentiated NEC and GIST discovered incidentally during surgical treatment of the NEC. Immunohistochemistry analysis showed that the NEC tumor cells were positive for CK (cytokeratin), CD57, synaptophysin, chromogranin, CD117 (KIT protein), Dog-1 (discovered on GIST-1 protein) and CD34. The synchronous GIST immunophenotype showed positivity for CD117, Dog-1 and CD34 (100%), whereas staining for CK, SMA, desmin and S100 was negative. Ki-67 labeling of proliferating cells was 90% in NEC and 1% in GIST. An accurate diagnosis was confirmed by immunohistochemical findings. Furthermore, genetic analysis using PCR direct sequencing identified no mutations in the KIT (exons 9, 11, 13 and 17) and PDGFRA (exons 12 and 18) genes. The patient developed lymph node metastases and underwent cisplatin-based chemotherapy after the operation. This is the first documented case of synchronous gastric GIST and NEC with the examination of protein expression and gene mutations in KIT and PDGFRA, which will help to further understand the etiology and pathogenesis of NEC coexisting with GIST in a gastric location.