STK33 Promotes the Growth and Progression of Human Pancreatic Neuroendocrine Tumour via Activation of the PI3K/AKT/mTOR Pathway

Unbiased comparison and modularization identify time-related transcriptomic reprogramming in exercised rat cartilage: Integrated data mining and experimental validation

Exercise is indispensable for maintaining cartilage integrity in healthy joints and remains a recommendation for knee osteoarthritis. Although the effects of exercise on cartilage have been implied, the detailed mechanisms, such as the effect of exercise time which is important for exercise prescription, remain elusive. In this study, bioinformatic analyses, including unbiased comparisons and modularization, were performed on the transcriptomic data of rat cartilage to identify the time-related genes and signaling pathways. We found that exercise had a notable effect on cartilage transcriptome. Exercise prominently suppressed the genes related to cell division, hypertrophy, catabolism, inflammation, and immune response. The downregulated genes were more prominent and stable over time than the upregulated genes. Although exercise time did not prominently contribute to the effects of exercise, it was a factor related to a batch of cellular functions and signaling pathways, such as extracellular matrix (ECM) homeostasis and cellular response to growth factors and stress. Two clusters of genes, including early and late response genes, were identified according to the expression pattern over time. ECM organization, BMP signaling, and PI3K-Akt signaling were early responsive in the exercise duration. Moreover, time-related signaling pathways, such as inositol phosphate metabolism, nicotinate/nicotinamide metabolism, cell cycle, and Fc epsilon RI signaling pathway, were identified by unbiased mapping and polarization of the highly time-correlated genes. Immunohistochemistry staining showed that Egfr was a late response gene that increased on day 15 of exercise. This study elucidated time-related transcriptomic reprogramming induced by exercise in cartilage, advancing the understanding of cartilage homeostasis.

Targeting PI3K/AKT/mTOR Signaling Pathway in Pancreatic Cancer: From Molecular to Clinical Aspects

Although pancreatic cancer (PC) was considered in the past an orphan cancer type due to its low incidence, it may become in the future one of the leading causes of cancer death. Pancreatic ductal adenocarcinoma (PDAC) is the most frequent type of PC, being a highly aggressive malignancy and having a 5-year survival rate of less than 10%. Non-modifiable (family history, age, genetic susceptibility) and modifiable (smoking, alcohol, acute and chronic pancreatitis, diabetes mellitus, intestinal microbiota) risk factors are involved in PC pathogenesis. Chronic inflammation induced by various factors plays crucial roles in PC development from initiation to metastasis. In multiple malignant conditions such as PC, cytokines, chemokines, and growth factors activate the class I phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) (PI3K/AKT/mTOR) signaling pathway, which plays key roles in cell growth, survival, proliferation, metabolism, and motility. Currently, mTOR, AKT, and PI3K inhibitors are used in clinical studies. Moreover, PI3K/mTOR dual inhibitors are being tested in vitro and in vivo with promising results for PC patients. The main aim of this review is to present PC incidence, risk factors, tumor microenvironment development, and PI3K/AKT/mTOR dysregulation and inhibitors used in clinical, in vivo, and in vitro studies.

Phosphatidylinositol 3-Kinase/Protein Kinase B/Mammalian Target of the Rapamycin Pathway-Related Protein Expression in Lung Squamous Cell Carcinoma and Its Correlation with Lymph Node Metastasis

The targeted therapy of lung squamous cell carcinoma (LSCC), a pathological type of non-small-cell lung cancer, is relatively lacking by contrast with lung adenocarcinoma. The overexpression or inhibition of intracellular signaling pathways leads to disease. To evaluate genes for a targeted therapy in LSCC, we analyzed PI3K pathway components in LSCC tissues and found elevated PI3K levels in LSCC tissues compared with adjacent counterparts. A comparison of PI3K levels in tissues with and without metastasis revealed that the PI3K pathway activity was greatly increased in metastatic tissues. Our findings suggest that the metastasis of cancer cells in patients with LSCC is closely related to the overexpression of PI3K pathway components in cancer tissues. We performed in vitro cell culture experiments and found that inhibition of PI3K activity decreased proliferation and increased apoptosis in H520 cells, suggesting that PI3K pathway inhibition limits LSCC cell proliferation. We hypothesize that LSCC metastasis is related to the overexpression of PI3K pathway components and inhibiting this pathway may help reduce the risk of lymph node metastasis in LSCC patients.

A Radiosensitivity Prediction Model Developed Based on Weighted Correlation Network Analysis of Hypoxia Genes for Lower-Grade Glioma

Background and Purpose

Hypoxia is one of the basic characteristics of the physical microenvironment of solid tumors. The relationship between radiotherapy and hypoxia is complex. However, there is no radiosensitivity prediction model based on hypoxia genes. We attempted to construct a radiosensitivity prediction model developed based on hypoxia genes for lower-grade glioma (LGG) by using weighted correlation network analysis (WGCNA) and least absolute shrinkage and selection operator (Lasso).

Methods

In this research, radiotherapy-related module genes were selected after WGCNA. Then, Lasso was performed to select genes in patients who received radiotherapy. Finally, 12 genes (AGK, ETV4, PARD6A, PTP4A2, RIOK3, SIGMAR1, SLC34A2, SMURF1, STK33, TCEAL1, TFPI, and UROS) were included in the model. A radiosensitivity-related risk score model was established based on the overall rate of The Cancer Genome Atlas (TCGA) dataset in patients who received radiotherapy. The model was validated in TCGA dataset and two Chinese Glioma Genome Atlas (CGGA) datasets. A novel nomogram was developed to predict the overall survival of LGG patients.

Results

We developed and verified a radiosensitivity-related risk score model based on hypoxia genes. The radiosensitivity-related risk score served as an independent prognostic indicator. This radiosensitivity-related risk score model has prognostic prediction ability. Moreover, a nomogram integrating risk score with age and tumor grade was established to perform better for predicting 1-, 3-, and 5-year survival rates.

Conclusions

We developed and validated a radiosensitivity prediction model that can be used by clinicians and researchers to predict patient survival rates and achieve personalized treatment of LGG.

NFYB potentiates STK33 activation to promote cisplatin resistance in diffuse large B-cell lymphoma

BACKGROUND

The aberrant expression of serine/threonine kinase 33 (STK33) has been implicated in cancers. However, its clinical significance and biological functions in diffuse large B cell lymphoma (DLBCL) remain largely unknown. In the present investigation, we delineated the expression of STK33 in DLBCL and its function in cisplatin resistance.

METHODS

First, genes associated with drug resistance as well as occurrence in DLBCL were analyzed by bioinformatics, followed by correlation analysis between STK33 expression and clinical baseline information of patients with DLBCL. Further, cisplatin-resistant DLBCL cell lines were constructed, and changes in cell sensitivity to cisplatin treatment were examined after interfering the expression of STK33 in parental cells as well as in drug-resistant cells, respectively. Subsequently, the downstream signaling pathways of STK33 were analyzed. Finally, the upstream regulatory mechanism of STK33 was predicted by bioinformatics as well as experimentally validated.

RESULTS

STK33 was overexpressed in the patients with DLBCL as well as in cisplatin-resistant DLBCL cells, and knockdown of STK33 significantly promoted sensitivity of resistant cells to cisplatin. Moreover, our further analysis revealed that STK33 promoted cisplatin resistance in DLBCL by activating the Hedgehog signaling pathway. We found in subsequent experiments that nuclear transcription factor Y subunit beta (NFYB) can bind to the STK33 promoter and thus promote STK33 expression.

CONCLUSIONS

The transcription factor NFYB expedites the transcription of SYK33 by binding to the STK33 promoter, thereby activating the Hedgehog signaling pathway in DLBCL cells, which in turn promotes the resistance of DLBCL cells to cisplatin.

Angiotensin II enhances the proliferation of Natural Killer/T-cell lymphoma cells via activating PI3K/Akt signaling pathway

The present study was to determine the roles of Angiotensin (Ang) II in the growth of lymphoma in nude mice and the proliferation and viability of the human Natural Killer/T (NK/T)-cell lymphoma cell line SNK-6, and the activation of downstream signaling pathway. Lymphoma samples and corresponding normal tissues were obtained from lymphoma patients. Proliferation of SNK-6 cells was detected by CCK8 or MTT assay. The levels of Ang II and its receptor Ang II type 1 receptor (AT1R) were higher in lymphoma tissues than those in control tissues. Ang II increased the lymphoma volume and size in nude mice, the proliferation and viability and the proliferating cell nuclear antigen (PCNA) and Ki67 levels of SNK-6 cells. Losartan, an antagonist of AT1R, reduced lymphoma volume and size in nude mice, and the proliferation and viability and the PCNA and Ki67 levels of SNK-6 cells. The levels of phosphorylated phosphatidylinositol 3-kinase (p-PI3K) and phosphorylated protein kinase B (p-Akt) were increased by Ang II and then reduced by losartan in SNK-6 cells. The proliferation and viability of SNK-6 cells were increased by Ang II, but these increases were inhibited by PI3K inhibitor wortmannin and Akt inhibitor MK2206. The increases of PCNA and Ki67 induced by Ang II were inhibited by wortmannin or MK2206 in SNK-6 cells. These results indicate that Ang II/AT1R is activated in lymphoma, and Ang II promotes the progression of lymphoma in nude mice and the proliferation and viability of SNK-6 cells via activating PI3K/Akt signaling pathway.

MNAT1 promotes proliferation and the chemo-resistance of osteosarcoma cell to cisplatin through regulating PI3K/Akt/mTOR pathway

Background

MNAT1 (menage a trois 1, MAT1), a cyclin-dependent kinase-activating kinase (CAK) complex, highly expressed in diverse cancers and was involved in cancer molecular pathogenesis. However, its deliverance profile and biological function in osteosarcoma (OS) remain unclear.

Methods

The expression of MNAT1 in OS was detected by western blot (WB) and immunohistochemistry (IHC). The potential relationship between MNAT1 molecular level expression and OS clinical expectations were analyzed according to tissues microarray (TMA). Proliferation potential of OS cells was evaluated in vitro based on CCK8 and OS cells colony formation assays, while OS cells transwell and in situ tissue source wound healing assays were employed to analyze the OS cells invasion and migration ability in vitro. A nude mouse xenograft model was used to detect tumor growth in vivo. In addition, ordinary bioinformatics analysis and experimental correlation verification were performed to investigate the underlying regulation mechanism of OS by MNAT1.

Results

In this research, we found and confirmed that MNAT1 was markedly over-expressed in OS tissue derived in situ, also, highly MNAT1 expression was closely associated with bad clinical expectations. Functional studies had shown that MNAT1 silencing could weaken the invasion, migration and proliferation of OS cells in vitro, and inhibit OS tumor growth in vivo. Mechanism study indicated that MNAT1 contributed to the progression of OS via the PI3K/Akt/mTOR pathway. We further verified that the MNAT1 was required in the regulation of OS chemo-sensitivity to cisplatin (DDP).

Conclusions

Taken together, the data of the present study demonstrate a novel molecular mechanism of MNAT1 involved in the formation of DDP resistance of OS cells.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-020-07687-3.

miR-107 inhibited malignant biological behavior of non-small cell lung cancer cells by regulating the STK33/ERK signaling pathway in vivo and vitro

Background

The role of miRNAs in non-small cell lung cancer (NSCLC) has been broadly studied and confirmed, and miR-107 has attracted an ever-growing level of attention. This study set out to research the mechanism of the effect of miR-107 on the malignant biological behavior of NSCLC in vivo and vitro.

Methods

The expression of miRNAs related to the development of NSCLC was detected by RT-qPCR. Western blotting was carried out to detect expression levels of serine/threonine kinase 33 (STK33) and proteins related to the extracellular regulated protein kinases (ERK) signaling pathway, while cell proliferation was detected using cell counting kit-8 (CCK-8). The cell apoptosis rate was measured using flow cytometry. The invasion ability was detected by Transwell assay. In vivo tumor growth assays were performed on mice. The expression ERK signaling pathway-related proteins in vivo was evaluated by immunohistochemistry staining. The targeted relationship between miR-107 and STK33 was confirmed by the dual luciferase reporter gene.

Results

In NSCLC cell lines and tissues, miR-107 was downregulated. Overexpression of miR-107 inhibited malignant biological behavior of NSCLC cell lines, and suppressed tumor growth in vivo. In addition, STK33 is one of the target genes of miR-107. Therefore, miR-107 suppressed cell proliferation and invasion and promoted tumor growth in vivo and cell apoptosis of NSCLC in vitro. The mechanism was found to be miR-107 targeting STK33, and a lack of STK33 led to the activation of ERK signaling pathway.

Conclusions

miR-107 inhibited malignant biological behavior of NSCLC through regulation of the STK33/ERK signaling pathway.

Involvement of the γ1 subunit of the large-conductance Ca2+-activated K+ channel in the proliferation of human somatostatinoma cells

Pancreatic neuroendocrine tumors (pNETs) occur due to the abnormal growth of pancreatic islet cells and predominantly develop in the duodenal-pancreatic region. Somatostatinoma is one of the pNETs associated with tumors of pancreatic δ cells, which produce and secrete somatostatin. Limited information is currently available on the pathogenic mechanisms of somatostatinoma. The large-conductance Ca²⁺-activated K⁺ (BK_Ca) channel is expressed in several types of cancer cells and regulates cell proliferation, migration, invasion, and metastasis. In the present study, the functional expression of the BK_Ca channel was examined in a human somatostatinoma QGP-1 cell line. In QGP-1 cells, outward currents were elicited by membrane depolarization at pCa 6.5 (300 nM) in the pipette solution and inhibited by the specific BK_Ca channel blocker, paxilline. Paxilline-sensitive currents were detected, even at pCa 8.0 (10 nM) in the pipette solution, in QGP-1 cells. In addition to the α and β2-4 subunits of the BK_Ca channel, the novel regulatory γ1 subunit (BK_Caγ1) was co-localized with the α subunit in QGP-1 cells. Paxilline-sensitive currents at pCa 8.0 in the pipette solution were reduced by the siRNA knockdown of BK_Caγ1. Store-operated Ca²⁺ entry was smaller in BK_Caγ1 siRNA-treated QGP-1 cells. The proliferation of QGP-1 cells was attenuated by paxilline or the siRNA knockdown of BK_Caγ1. These results strongly suggest that BK_Caγ1 facilitates the proliferation of human somatostatinoma cells. Therefore, BK_Caγ1 may be a novel therapeutic target for somatostatinoma.

Prognostic and predictive factors on overall survival and surgical outcomes in pancreatic neuroendocrine tumors: recent advances and controversies

Introduction: Recent advances in diagnostic modalities and therapeutic agents have raised the importance of prognostic factors in predicting overall survival, as well as predictive factors for surgical outcomes, in tailoring therapeutic strategies of patients with pancreatic neuroendocrine neoplasms (panNENs).Areas covered: Numerous recent studies of panNEN patients report the prognostic values of a number of clinically related factors (clinical, laboratory, imaging, treatment-related factors), pathological factors (histological, classification, grading) and molecular factors on long-term survival. In addition, an increasing number of studies showed the usefulness of various factors, specifically biomarkers and molecular makers, in predicting recurrence and mortality related to surgical treatment. Recent findings (from the last 3 years) in each of these areas, as well as recent controversies, are reviewed.Expert commentary: The clinical importance of prognostic and predictive factors for panNENs is markedly increased for both overall outcome and post resection, as a result of recent advances in all aspects of the diagnosis, management and treatment of panNENs. Despite the proven prognostic utility of routinely used tumor grading/classification and staging systems, further studies are required to establish these novel prognostic factors to support their routine clinical use.