Protein kinase C Inhibitors selectively modulate dynamics of cell adhesion molecules and cell death in human colon cancer cells

Targeting SMAD-Dependent Signaling: Considerations in Epithelial and Mesenchymal Solid Tumors

SMADs are the canonical intracellular effector proteins of the TGF-β (transforming growth factor-β). SMADs translocate from plasma membrane receptors to the nucleus regulated by many SMAD-interacting proteins through phosphorylation and other post-translational modifications that govern their nucleocytoplasmic shuttling and subsequent transcriptional activity. The signaling pathway of TGF-β/SMAD exhibits both tumor-suppressing and tumor-promoting phenotypes in epithelial-derived solid tumors. Collectively, the pleiotropic nature of TGF-β/SMAD signaling presents significant challenges for the development of effective cancer therapies. Here, we review preclinical studies that evaluate the efficacy of inhibitors targeting major SMAD-regulating and/or -interacting proteins, particularly enzymes that may play important roles in epithelial or mesenchymal compartments within solid tumors.

Verproside, the Most Active Ingredient in YPL-001 Isolated from Pseudolysimachion rotundum var. subintegrum, Decreases Inflammatory Response by Inhibiting PKCδ Activation in Human Lung Epithelial Cells

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease which causes breathing problems. YPL-001, consisting of six iridoids, has potent inhibitory efficacy against COPD. Although YPL-001 has completed clinical trial phase 2a as a natural drug for COPD treatment, the most effective iridoid in YPL-001 and its mechanism for reducing airway inflammation remain unclear. To find an iridoid most effectively reducing airway inflammation, we examined the inhibitory effects of the six iridoids in YPL-001 on TNF or PMA-stimulated inflammation (IL-6, IL-8, or MUC5AC) in NCI-H292 cells. Here, we show that verproside among the six iridoids most strongly suppresses inflammation. Both TNF/NF-κB-induced MUC5AC expression and PMA/PKCδ/EGR-1-induced IL-6/-8 expression are successfully reduced by verproside. Verproside also shows anti-inflammatory effects on a broad range of airway stimulants in NCI-H292 cells. The inhibitory effect of verproside on the phosphorylation of PKC enzymes is specific to PKCδ. Finally, in vivo assay using the COPD-mouse model shows that verproside effectively reduces lung inflammation by suppressing PKCδ activation and mucus overproduction. Altogether, we propose YPL-001 and verproside as candidate drugs for treating inflammatory lung diseases that act by inhibiting PKCδ activation and its downstream pathways.

FSIP1 Is Associated with Poor Prognosis and Can Be Used to Construct a Prognostic Model in Gastric Cancer

Gastric cancer (GC) is one of the most common upper gastrointestinal malignant tumors, and the incidence of the GC shows an increasing trend in the past years. Finding more sensitive markers will help to reveal the mechanism of GC progression and clinic diagnoses. This study first analyzed the mRNA expression level of FSIP1 in TCGA GC samples and the significance in predicting the prognosis. KEGG and GO analyses were used to explore the molecular mechanism of FSIP1 in GC progression. This study further retrospectively analyzed 166 clinical samples of GC from Harbin Medical University Cancer Hospital and evaluated the expression level of FSIP1 by immunohistochemistry. Kaplan-Meier and Cox multivariate analysis was used to investigate the prognostic value of FSIP1 expression in GC patients. We also identified correlations between FSIP1 and clinicopathological characteristics. This study found that the mRNA level of FSIP1 was significantly upregulated in GC compared with nontumor specimens and correlated with poor prognosis. Immunohistochemistry confirmed the results of bioinformatics analysis of the TCGA GC database. FSIP1 was associated with pTNM pathological stage, tumor location, and neural invasion. In addition, multivariate Cox regression analysis showed that FSIP1, T classification, and N classification were independent posterior factors of patients and could be combined with pathological features to construct a nomogram prognostic model. Overall, our results suggest that FSIP1 is expected to be an independent prognostic indicator of GC.

Tectoridin inhibits the progression of colon cancer through downregulating PKC/p38 MAPK pathway

Colon cancer is one of the most familiar malignancies worldwide, with high morbidity and high mortality. This study intended to explore the role and mechanism of tectoridin (TEC) in regulating the progression of colon cancer. First, colon cancer cell lines (HCT116 and SW480 cells) were treated with different doses of TEC (0-200 μM). Then, CCK8 and clone formation experiments were performed to detect cell proliferation. Flow cytometry and western blot were conducted to examine apoptosis. Subsequently, Transwell assay and wound-healing test was employed to determine the effect of TEC on colon cancer cell invasion and migration. Next, western blot was performed to monitor the PKC/p38 MAPK pathway activation. In addition, a tumor model was established in nude mice to explore the effect of TEC on tumor growth in vivo. TEC dose-dependently dampened the proliferation, migration and invasion of colon cancer cells and facilitated their apoptosis. In addition, TEC abated the tumor cell growth in vivo. Besides, TEC dose-dependently suppressed the expression of PKC and p38 MAPK. Moreover, inhibiting the PKC pathway almost cancel out the anti-tumor effects induced by TEC. TEC attenuates the colon cancer progression by inhibiting the PKC/p38 MAPK pathway.

Increased phospholipase D activity contributes to tumorigenesis in prostate cancer cell models

Prostate cancer (PCa) is the most frequent cancer among men and the first cause of death over 65. Approximately 90% of patients with advanced disease will develop bone metastasis, which dramatically reduces long-term survival. Therefore, effective therapies need to be developed, especially when disease is still well-localized. Phospholipase D (PLD), an enzyme that hydrolyzes phosphatidylcholine to yield phosphatidic acid, regulates several cellular functions as proliferation, survival, migration or vesicular trafficking. PLD is implicated in numerous diseases such as neurodegenerative, cardiovascular, autoimmune disorders or cancer. Indeed, PLD controls different aspects of oncogenesis including tumor progression and resistance to targeted therapies such as radiotherapy. PLD1 and PLD2 are the only isoforms with catalytic activity involved in cancer. Surprisingly, studies deciphering the role of PLD in the pathophysiology of PCa are scarce. Here we describe the correlation between PLD activity and PLD1 and PLD2 expression in PCa bone metastasis-derived cell lines C4-2B and PC-3. Next, by using PLD pharmacological inhibitors and RNA interference strategy, we validate the implication of PLD1 and PLD2 in cell viability, clonogenicity and proliferation of C4-2B and PC-3 cells and in migration capacity of PC-3 cells. Last, we show an increase in PLD activity as well as PLD2 protein expression during controlled starvation of PC-3 cells, concomitant with an augmentation of its migration capacity. Specifically, upregulation of PLD activity appears to be PKC-independent. Taken together, our results indicate that PLD, and in particular PLD2, could be considered as a potential therapeutic target for the treatment of PCa-derived bone metastasis.

Clinical significance of expression of fibrous sheath interacting protein 1 in colon cancer

BACKGROUND

The occurrence and development of colon cancer are complex, involving a variety of genetic changes, such as mutation and activation of oncogenes, inactivation of tumour suppressor genes, and aberrant proliferation and apoptosis regulation mechanisms. Fibrous sheath interacting protein 1 (FSIP1) is a newly discovered oncogene that is frequently activated in a variety of tumours such as breast cancer and bladder cancer. However, the clinical significance of FSIP1 in colon cancer is unclear. In this study, we analysed the clinical significance of expression of FSIP1 in human colon cancer, aimed to clarify the biological role of FSIP1 in the development and progression of colon cancer.

AIM

To investigate the clinical significance of expression of FSIP1 in colon cancer.

METHODS

From March 2011 to March 2014, 302 specimens of tumour tissues and paracancerous tissues were obtained from patients pathologically diagnosed with colon cancer at Shengjing Hospital of China Medical University. Immunohistochemistry was used to detect FSIP1 expression in colon cancer tissues and adjacent normal tissues. Spearman correlation coefficient and Cox regression analyses were used to determine the relationship between FSIP1 expression and clinicopathological factors and prognosis, as well as the impact on survival.

RESULTS

Compared with its expression in adjacent normal tissues, FSIP1 was expressed at higher levels in colon cancer tissues. Spearman correlation analysis showed that high expression of FSIP1 was positively correlated with clinicopathological stage, lymph node metastasis, and poor prognosis in colon cancer; it was negatively correlated with the degree of tumour differentiation. Cox regression analysis showed that high FSIP1 expression was an independent risk factor for the prognosis of colon cancer patients.

CONCLUSION

High expression of FSIP1 may be one of the important factors affecting the clinical outcome of colon cancer patients and leading to poor prognosis.