Pharmacological Mechanisms of Kirenol against Ovarian Carcinoma: A Network Pharmacology and Experimental Validation Study In Vitro

BACKGROUND

Ovarian carcinoma is an aggressive gynecological malignancy. Kirenol, a diterpene compound, has recently gained attention for its potential anticancer properties. However, its exact anti-tumor mechanism remains largely unexplored.

OBJECTIVE

In this study, we explored the inhibitory effects of Kirenol on ovarian cancer using network pharmacology and in vitro experiments and elucidated its underlying mechanisms.

METHODS

Through the utilization of molecular docking, we established a network of proteinprotein interactions (PPI), which unveiled CDK4 as an essential target. Additionally, gene enrichment and pathway analysis highlighted the significance of the PI3K/AKT pathway. The viability of ovarian cancer cells and normal ovarian epithelial cells was evaluated using CCK8 assays to determine the effect of Kirenol. Following in vitro tests, cell colony formation, wound healing, flow cytometry, and Western blotting were conducted to assess its impact on cell proliferation, metastasis, apoptosis, and the cell cycle.

RESULTS

Kirenol significantly reduced the viability of ovarian cancer cells (SKOV3 and A2780) compared to normal ovarian epithelial cells (IOSE-80). Moreover, Kirenol efficiently suppressed the growth and movement, caused a cell cycle halt, and stimulated programmed cell death in SKOV3 and A2780 cells. Through molecular analysis, it was observed that Kirenol increased the expression of Bax while decreasing the expression of MMP2, MMP9, and Bcl-2. It also attenuated the phosphorylation of PI3K, AKT, and RB and downregulated CDK4 and CCND1 expression. Notably, co-treatment with the PI3K pathway inhibitor LY294002 enhanced the inhibitory effect of Kirenol on ovarian cancer cells.

CONCLUSION

In summary, the combined results of our network pharmacology analysis and in vitro tests emphasized that Kirenol hinders the growth of ovarian cancer cells, causes cell cycle arrest, enhances apoptosis, and hampers migration, possibly by regulating the PI3K/AKT/CDK4 signaling pathway.

BRAF V600E immunohistochemistry as a useful tool in the diagnosis of melanomas with ambiguous morphologies and immunophenotypes

We report three melanoma cases in which BRAF V600E immunohistochemistry (IHC) was valuable for diagnosis. Patient 1: In a patient with a history of primary melanoma on the chest and metastatic melanoma to right breast after undergoing multiple local and systemic therapies, a lung metastasis exhibited chondroid differentiation, aberrant myofibroblastic marker expression, and rare pancytokeratin positivity, without melanocytic marker expression. Patient 2: After targeted and immunotherapy for primary melanoma on the scalp as well as regional and distant metastatic melanoma, an omental metastasis showed CDX2-positive glandular structures that were negative for melanocytic markers. It was initially misdiagnosed as primary gastrointestinal adenocarcinoma. Patient 3: A patient with history of melanoma showing epithelioid morphology on the right thigh presented with multiple soft tissue nodules on skin, lymph nodes and internal organs after being lost to follow-up for 4 years. A biopsy specimen from the right thigh showed spindled cells with scattered pancytokeratin cocktail positivity and ambiguous staining for melanocytic markers. For melanomas with ambiguous morphologies and/or immunophenotypes in each of the three patients, BRAF V600E expression by IHC was maintained in both primary and metastatic melanoma specimens examined. These cases highlight the utility of BRAF V600E IHC in the diagnosis of melanoma.

Internal Wireless Electrical Stimulation from Piezoelectric Barium Titanate Nanoparticles as a New Strategy for the Treatment of Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is an aggressive BC subtype with a higher metastatic rate and a worse 5-year survival ratio than the other BC. It is an urgent need to develop a noninvasive treatment with high efficiency to resist TNBC cell proliferation and invasion. Internal wireless electric stimulation (ES) based on piezoelectric materials is an emerging noninvasive strategy, with adjustable ES intensity and excellent biosafety. In this study, three different barium titanate nanoparticles (BTNPs) with different crystal phases and piezoelectric properties were studied. Varying intensities of internal ES were generated from the three BTNPs (i.e., BTO, U-BTO, P-BTO). In vitro tests revealed that the internal ES from BTNPs was efficient at reducing the proliferative potential of cancer cells, particularly BC cells. In vitro experiments on MDA-MB-231, a typical TNBC cell line, further revealed that the internal wireless ES from BTNPs significantly inhibited cell growth and migration up to about 82% and 60%, respectively. In vivo evaluation of MDA-MB-231 tumor-bearing mice indicated that internal ES not only resisted almost 70% tumor growth but also significantly inhibited lung metastasis. More importantly, in vitro and in vivo studies demonstrated a favorable correlation between the anticancer impact and the intensities of ES. The underlying mechanism of MDA-MB-231 cell proliferation and metastasis inhibition caused by internal ES was also investigated. In summary, our results revealed the effect and mechanism of internal ES from piezoelectric nanoparticles on TNBC cell proliferation and migration regulation and proposed a promising noninvasive therapeutic strategy for TNBC with minimal side effects while exhibiting good therapeutic efficiency.

Calotropis procera induced caspase dependent apoptosis and impaired Akt/mTOR signaling in 4T1 breast cancer cells

INTRODUCTION

Calotropis procera (Aiton) Dryand (Apocynaceae) is an herb that has been commonly used in folk medicine to treat various diseases for more than 1500 years.

AIMS

Our goal was to investigate the anti-metastatic effects of phenolics extracted from C. procera (CphE) against 4T1 breast cancer cells and in BALB/c mice.

METHODS

4T1 cells were treated with CphE and quercetin (as positive control) at concentrations that inhibited cell viability by 50% (IC50). Levels of reactive oxygen species (ROS), wound healing, and gene and protein expressions were determined following standard protocols. For the in vivo pilot study, the syngeneic BALB/c mouse model was used. 4T1 cells were injected into mammary fat pads. Tumors were allowed to grow for 9 days before gavage treatment with CphE (150 mg GAE/kg/day) or PBS (controls) for one week. Excised tumors, liver, and lungs were analyzed for gene and protein expression and histology.

RESULTS

In vitro results showed that CphE suppressed cell viability through apoptosis induction, via caspase-3 cleavage and total PARP reduction. CphE also scavenged ROS and suppressed Akt, mTOR, ERK1/2, CREB, and Src activation contributing to cell motility inhibition. CphE reduced IR, PTEN, TSC2, p70S6, and RPS6, protein levels, which are proteins involved in the PI3K/Akt/mTOR pathway, suggesting this pathway as CphE primary target. In vivo results showed downregulation of ERK1/2 activation by phosphorylation in tumor tissues, accompanied by angiogenesis reduction in tumor and lung tissues. A reduction of Cenpf mRNA levels in liver and lung tissues strongly suggested anti-invasive cancer activity of CphE.

CONCLUSION

CphE inhibited 4T1 cell signal pathways that play a key role in cell growth and invasion. The potential for in vitro results to be translated in vivo was confirmed. A complete animal study is guarantee to confirm the CphE anticancer and antimetastatic activity in vivo.

Metastasis of lung carcinoid in the thyroid gland after 18 years: it is never too late. A case report and review of the literature

Metastasis to the thyroid gland is a rare event. To date, only 11 cases of metastasis from neuroendocrine tumors (NETs) originating in the lung have been reported. We present a case of a patient in his 40s harboring two nodules in the thyroid gland that were diagnosed as well-differentiated NET (G1). Eighteen years before the patient underwent a lung lobectomy of the right upper lobe for a bronchial typical carcinoid with metastasis in one lymph node. Normal blood levels of calcitonin virtually ruled out the diagnosis of medullary thyroid carcinoma (MTC) and supported the diagnosis of a possible thyroid metastasis of the previous bronchial NET. Mutational analysis performed on both primary and metastasis tumor tissue did not show any mutation in the 409 genes analyzed.

Adenoid Cystic Carcinoma of the Breast

BACKGROUND

Contrast-enhanced spectral mammogram (CESM) is a modern technique providing additional information to detect or diagnose breast cancers.

INTRODUCTION

We present a rare ACC of the breast on CESM.

METHODS

A 49-year-old woman with surgicopathological proved ACC was reported with tumor features on CESM, sonography and contrast-enhanced magnetic resonance imaging (CE-MRI).

RESULTS

Sonography revealed a 1.4 cm × 1.2 cm × 1 cm circumscribe round mass in the upper outer quadrant of the left breast that was diagnosed with fibroadenoma. The mammogram did not show any discernible mass, however, the recombined subtracted images displayed a circumscribe mass with thin rim enhancement and enhanced internal patches that were resembling CE-MRI. Finally, the mass was proved to ACC.

CONCLUSION

CESM facilitates the detection of isodense cancer and provides the enhanced features for differential diagnosis. Resembling CE-MRI, CESM displayed rim enhancement and internal enhanced patches as diagnostic clues for this case of ACC.

Sam68 Promotes the Progression of Human Breast Cancer through inducing Activation of EphA3

BACKGROUND

Src associated with mitosis of 68 kDa (Sam68), is often highly expressed in human cancers. Overexpression of Sam68 has been shown to be correlated with poor survival prognosis in some cancer patients. However, little is known whether Sam68 plays a role in promoting metastasis in breast cancer.

MATERIALS AND METHODS

The expression of Sam68 protein in breast cancer tissue was detected by immunohistochemistry. Trans-well assay, wound-healing, real-time PCR and Western blotting analysis were used to detect the effect of Sam68 on promoting EMT or metastasis of breast cancer. Next-generation RNA sequencing was used to analyze genes that may be regulated by Sam68.

RESULTS

Sam68 plays a positive role in promoting breast cancer metastasis. Sam68 was found to be overexpressed in breast cancer along with lymph node metastasis. MMP-9 was also found to be overexpressed in breast cancer tissue and was correlated to the expression of Sam68 (P<0.01). Xenograft in NOD/SCID mice and in vitro experiments confirmed that the invasion and metastatic ability of breast cancer cells were regulated by Sam68. And EPHA3 could be up-regulated by Sam68 in breast cancer.

CONCLUSION

High expression of Sam68 participates in breast cancer metastasis by up-regulating the EPHA3 gene.

Glucose-Regulated Protein 94 Mediates the Proliferation and Metastasis through the Regulation of ETV1 and MAPK Pathway in Colorectal Cancer

Colorectal cancer (CRC) is a worldwide health problem. Glucose-regulated protein 94 (GRP94) is known as an important endoplasmic reticulum-stress response protein that shows correlation with aggressive cancer behavior. However, the role of GRP94 in CRC is still unclear. Our results showed that silencing GRP94 (GRP94-KD) reduced cell proliferation, invasion and migration of CRC cells and suppressed tumorigenesis in the xenograft mouse model. Rescue assay showed that ETV1 overexpression reversed the effect of GRP94 on cell proliferation and migration. In the molecular mechanism, we found that knockdown of GRP94 inhibited the level of MAPK pathway, including ERK/p-ERK, JNK/p-JNK, and p38/p-p38 signals. Cyclooxygenase-2 and epithelial-mesenchymal transformation biomarkers, such as N-cadherin, vimentin, and β-catenin were suppressed in GRP94 knockdown cells. Treatment of specific inhibitors of MAPK pathway showed that ERK/p-ERK, and p38/p-p38 inhibitors significantly influenced ETV1 expression as compared to JNK/p-JNK inhibitor. Our results indicated that silencing GRP94 repressed the ability of EMT process, cancer cell proliferation, metastasis, and CRC tumorigenesis. Therefore, GRP94 may play an important role in CRC by regulating ETV1 and MAPK pathway.

MicroRNA-362 negatively and positively regulates SMAD4 expression in TGF-β/SMAD signaling to suppress cell migration and invasion

Cell migration and invasion are modulated by epithelial-to-mesenchymal transition (EMT) and the reverse MET process. Despite the detection of microRNA-362 (miR-362, both the miR-362-5p and -3p species) in cancers, none of the identified miR-362 targets is a mesenchymal or epithelial factor to link miR-362 with EMT/MET and metastasis. Focusing on the TGF-β/SMAD signaling pathway in this work, luciferase assays and western blot data showed that miR-362 targeted and negatively regulated expression of SMAD4 and E-cadherin, but not SNAI1, which is regulated by SMAD4. However, miR-362 knockdown also down-regulated SMAD4 and SNAI1, but up-regulated E-cadherin expression. Wound-healing and transwell assays further showed that miR-362 knockdown suppressed cell migration and invasion, effects which were reversed by over-expressing SMAD4 or SNAI1, or by knocking down E-cadherin in the miR-362 knockdown cells. In orthotopic mice, miR-362 knockdown inhibited metastasis, and displayed the same SMAD4 and E-cadherin expression profiles in the tumors as in the in vitro studies. A scheme is proposed to integrate miR-362 negative regulation via SMAD4, and to explain miR-362 positive regulation of SMAD4 via miR-362 targeting of known SMAD4 suppressors, BRK and DACH1, which would have resulted in SMAD4 depletion and annulment of subsequent involvement in TGF-β signaling actions. Hence, miR-362 both negatively and positively regulates SMAD4 expression in TGF-β/SMAD signaling pathway to suppress cell motility and invasiveness and metastasis, and may explain the reported clinical association of anti-miR-362 with suppressed metastasis in various cancers. MiR-362 knockdown in miR-362-positive cancer cells may be used as a therapeutic strategy to suppress metastasis.

Novel Polymethoxylated Chalcones as Potential Compounds Against KRAS-Mutant Colorectal Cancers

BACKGROUND/OBJECTIVE

KRAS-mutant colorectal cancers (CRC) are tumors that are associated with poor prognosis. However, no effective treatments are available to target them. Therefore, we designed and synthesized novel chalcone analogs, small organic molecules, to investigate their effects on KRAS-mutant CRC cells.

METHODS

Fourteen new chalcone analogs were synthesized, optimized, characterized, and tested against two KRAS-mutant CRC cell lines (HCT-116 and LoVo), one p-53 and BRAF mutant CRC cell line (HT-29) and one normal immortalized colon cells (NCE-1 E6/E7). Effects on cell viability, apoptosis, cell cycle, migration, colony formation, EMT, and angiogenesis were investigated.

RESULTS

Compounds 3 and 14 were the most effective. Compound 3 showed potent activity against HCT-116 and LoVo cell lines (GI50 of 6.10 μM and 7.00 μM, respectively). While compound 14 showed GI50 of 8.60 μM and 8.80 μM on HCT-116 and LoVo cell lines, respectively. Both compounds were approximately 2-3 times more selective toward cancer cells rather than normal colon cells. Compound 3 was effective in inducing apoptosis in HCT-116 cells via Bax upregulation and Bcl-2 downregulation. Invasion and metastasis of KRAS-mutant cells were modulated by compounds 3 and 14 through significant inhibition of cell migration and the prevention of colony formation. In addition, they reversed EMT by downregulation of EMT markers (vimentin, fascin, and β- catenin) and upregulation of cell-cell adhesion marker, E-cadherin. Furthermore, compounds 3 and 14 had significantly inhibited angiogenesis in ovo.

CONCLUSION

Compounds 3 and 14 represent potent and selective leads for KRAS-mutant CRC cells, thus, further in vitro and in vivo studies are necessary to confirm their effect on KRAS-mutant CRCs.

Triple Negative Breast Cancer: How Neurokinin-1 Receptor Antagonists Could Be Used as a New Therapeutic Approach

Breast cancer (BC) is the most frequently diagnosed cancer and the leading cause of cancer death among females. BC cells not showing HER-2/Neu amplification and not expressing estrogen/ progesterone receptors are named triple-negative BC (TNBC) cells. TNBC represents 10-15% of all BC and is associated with an aggressive clinical course. TNBC patient prognosis, survival and response to current therapies are poor and for this reason, it is crucial to search for new therapeutic targets in TNBC to develop new therapeutic strategies. One of these targets is the neurokinin-1 receptor (NK-1R). It is well known that the substance P (SP)/NK-1R system is involved in cancer progression. TNBC cells overexpress the NK-1R and, after binding to this receptor, SP promotes the proliferation/ migration of TNBC cells. Non-peptide NK-1R antagonists (e.g., aprepitant) are known to exert, via the NK-1R, an antitumor action; TNBC cells die by apoptosis. In this review, we update the data on a promising therapeutic innovation: the use of NK-1R antagonists for the treatment of TNBC patients.

MiR-135-5p inhibits TGF-β-induced epithelial-mesenchymal transition and metastasis by targeting SMAD3 in breast cancer

Breast cancer (BC) is the most frequently diagnosed malignant tumors and the leading cause of death due to cancer in women around the world. A growing body of studies have documented that microRNA (miR)-135-5p is associated with the development and progression of BC. Considering that sekelsky mothers against dpp3 (SMAD3) plays a crucial role in transforming growth factor (TGF)-β/SMAD pathway and epithelial-mesenchymal transition (EMT) process, it is critical to elucidate the crosstalk and underlying regulatory mechanisms between miR-135-5p and SMAD3 in controlling TGF-β-mediated EMT in BC metastasis. Our results revealed a reciprocal expression pattern between miR-135-5p and SMAD3 mRNA in BC tissues and cell lines. Moreover, miR-135-5p was decreased in BC tissues compared to adjacent breast tissues; more interesting, miR-135-5p mRNA levels (Tumor/Normal, T/N) was further decreased in BC patients with lymph node metastasis, while SMAD3 mRNA levels were increased. Gain- and loss-of-function assays indicated that overexpression of miR-135-5p inhibited TGF-β-mediated EMT and BC metastasis in vitro and in vivo. Furthermore, knockdown of SMAD3 produced a consistent phenotype of miR-135-5p overexpression in breast cancer cells. Mechanistically, SMAD3, a pivotal transcriptional modulator of TGF-β/SMAD pathway, for the first time, was analyzed and identified as a target gene of miR-135-5p by bioinformatic algorithms and dual-luciferase reporter assays. Taken together, we clarified that miR-135-5p suppressed TGF-β-mediated EMT and BC metastasis by negatively regulating SMAD3 and TGF-β/SMAD signaling. Our findings supported that miR-135-5p may serve as a tumor suppressor, and be a valuable diagnostic biomarker for the treatment of BC.

Mogroside V Inhibits Hyperglycemia-induced Lung Cancer Cells Metastasis through Reversing EMT and Damaging Cytoskeleton

BACKGROUND

Diabetes Mellitus (DM) accelerates progress of lung cancer. Hyperglycemia, a critical feature of DM, promotes lung cancer metastasis. Mogroside V is a triterpenoid glycoside from Siraitia grosvenorii. Interestingly, mogroside V not only plays an anti-diabetic role, but also has anti-tumor effects.

OBJECTIVE

In this study, we investigated the metastatic efficiency of mogroside V in lung cancer cells cultured in hyperglycemia.

METHODS

Two lung cancer cell lines-A549 and H1299 were cultured in normoglycemia (5.5mM glucose) and hyperglycemia (25mM glucose). Cellular proliferation was tested by MTT, invasion was examined by transwell assay, migration was measured by wound healing assay, cytoskeleton was stained by Phalloidin-TRITC and the expressions of EMT markers and Rho-GTPase family protein were detected by western blot.

RESULTS

Hyperglycemia promoted the invasion and migration of A549 and H1299 cells compared with normoglycemia. Mogroside V inhibited the hyperglycemia-induced invasion and migration. Hyperglycemia promoted epithelial-mesenchymal transition (EMT), while mogroside V could reverse this process through up-regulating E-Cadherin expression and down-regulating N-Cadherin, Vimentin, Snail expressions. Furthermore, mogroside V fractured microfilaments and reduced Rho A, Rac1, Cdc42 and p-PAK1 expressions under hyperglycemic conditions.

CONCLUSION

These results suggest that mogroside V inhibits hyperglycemia-induced lung cancer cells migration and invasion through reversing EMT and damaging cytoskeleton.

Celastrus Orbiculatus Extracts Inhibit the Metastasis through Attenuating PI3K/Akt/mTOR Signaling Pathway in Human Gastric Cancer

BACKGROUND

Rapamycin receptor inhibitors have been applied in the clinic and achieved satisfactory therapeutic effect recently. The mechanisms did not clearly show how the Celastrus Orbiculatus Extracts (COE) inhibited the expression of the mammalian Target of Rapamycin (mTOR) in human gastric cancer cells. The aim of this study was to investigate whether the COE inhibited the metastasis through the mTOR signaling pathway in human gastric cancer MGC-803 cells.

METHODS

The abnormal expression level of mTOR protein was detected by immunohistochemistry in human gastric cancer tissue. The MGC-803/mTOR- cells were constructed by knockdown of mTOR using lentivirus infection technique. The human gastric cancer MGC-803/mTOR- cells were treated with different concentrations (20, 40, 80 μg/ml) of COE for 24 hours. The ability of cell metastasis was analyzed by the cell invasion and migration assay. The expression levels of PI3K/Akt/mTOR signaling pathway were detected by Western Blotting.

RESULTS

COE inhibited the proliferation, invasion and migration of MGC-803/mTOR- cells in a concentrationdependent manner. The expression of E-cadherin protein increased, and the expression of N-cadherin and Vimentin decreased simultaneously in the MGC-803/mTOR- cells. 4EBP1, p-4EBP1, P70S6k, p-P70S6k, mTOR, p-mTOR, PI3K and Akt proteins in MGC-803/mTOR- cells were reduced in a dose-dependent manner.

CONCLUSION

COE could not only inhibit cell growth, invasion and migration, but also inhibit the epithelialmesenchymal transition of gastric cancer cells. The molecular mechanism of COE inhibited the metastasis which may be related to the PI3K/Akt/mTOR signal pathway. This study provides ideas for the development of new anti-gastric cancer drugs.

DNA methylation maintains the CLDN1-EPHB6-SLUG axis to enhance chemotherapeutic efficacy and inhibit lung cancer progression

The loss of cancer-cell junctions and escape from the primary-tumor microenvironment are hallmarks of metastasis. A tight-junction protein, Claudin 1 (CLDN1), is a metastasis suppressor in lung adenocarcinoma. However, as a metastasis suppressor, the underlying molecular mechanisms of CLDN1 has not been well studied. Methods: The signaling pathway regulated by CLDN1 was analyzed by Metacore software and validated by immunoblots. The effect of the CLDN1-EPHB6-ERK-SLUG axis on the formation of cancer stem-like cells, drug resistance and metastasis were evaluated by sphere assay, aldefluor assay, flow cytometry, migration assay, cytotoxicity, soft agar assay, immunoprecipitation assay and xenograft experiments. Furthermore, the methylation-specific PCR, pyrosequencing assay, chromatin immunoprecipitation and reporter assay were used to study the epigenetic and RUNX3-mediated CLDN1 transcription. Finally, the molecular signatures of RUNX3/CLDN1/SLUG were used to evaluate the correlation with overall survival by using gene expression omnibus (GEO) data. Results: We demonstrated that CLDN1 repressed cancer progression via a feedback loop of the CLDN1-EPHB6-ERK1/2-SLUG axis, which repressed metastasis, drug resistance, and cancer stemness, indicating that CLDN1 acts as a metastasis suppressor. CLDN1 upregulated the cellular level of EPHB6 and enhanced its activation, resulting in suppression of ERK1/2 signaling. Interestingly, DNA hypermethylation of the CLDN1 promoter abrogated SLUG-mediated suppression of CLDN1 in low-metastatic cancer cells. In contrast, the histone deacetylase inhibitor trichostatin A or vorinostat facilitated CLDN1 expression in high-metastatic cancer cells and thus increased the efficacy of chemotherapy. Combined treatment with cisplatin and trichostatin A or vorinostat had a synergistic effect on cancer-cell death. Conclusions: This study revealed that DNA methylation maintains CLDN1 expression and then represses lung cancer progression via the CLDN1-EPHB6-ERK1/2-SLUG axis. Because CLDN1 enhances the efficacy of chemotherapy, CLDN1 is not only a prognostic marker but a predictive marker for lung adenocarcinoma patients who are good candidates for chemotherapy. Forced CLDN1 expression in low CLDN1-expressing lung adenocarcinoma will increase the chemotherapy response, providing a novel therapeutic strategy.

Long Noncoding RNA DCST1-AS1 Promotes Cell Proliferation and Metastasis in Triple-negative Breast Cancer by Forming a Positive Regulatory Loop with miR-873-5p and MYC

Background: DC-STAMP domain containing 1-antisense 1 (DCST1-AS1) is a long noncoding RNA (lncRNA) that is up-regulated in triple-negative breast cancer (TNBC) tissues. Here, we attempt to investigate the oncogenic property of DCST1-AS1.

Methods: LncRNA microarrays were used to detect differentially expressed lncRNA in cancerous tissues. Fluorescence in situ hybridization assay was used to detect the distribution of DCST1-AS1 in BT-549 and MDA-MB-231 cells. Lentiviral systems, inhibitors, siRNA and overexpression plasmids were used for gain- and loss-of-function experiments. Colony formation assay, wound healing assay, CCK8 assay, transwell assay, and flow cytometry assay were used to study the function of DCST1-AS1. Luciferase assay was used to verify the binding of MYC to the promoter region and the binding of miR-873-5p to DCST1-AS1. RNA immunoprecipitation assay was used to verify that argonaute 2 binds to both miR-873-5p and DCST1-AS1. Western blotting was used to measure changes in protein expression.

Results: Consistent with the microarray results, we found that DCST1-AS1 was up-regulated in both TNBC tissue samples and cell lines. DCST1-AS1 was positively correlated with distant metastasis and histopathological grades. DCST1-AS1 is distributed in both nucleus and cytoplasm. Knockdown of DCST1-AS1 inhibits TNBC cell proliferation and metastasis, while overexpression of DCST1-AS1 promotes TNBC cell proliferation and metastasis. We confirmed that DCST1-AS1 expression in TNBC cells is regulated by MYC. Furthermore, we found that DCST1-AS1 is negatively correlated with miR-873-5p in TNBC tissues and is a direct target gene of miR-873-5p. Argonaute 2 is involved in the binding of DCST1-AS1 and miR-873-5p and promotes the degradation of DCST1-AS1. The interaction of DCST1-AS1 with miR-873-5p ultimately up-regulated the expression of insulin-like growth factor 2 mRNA binding protein 1 (IGF2BP1), MYC, CD44 and lymphoid enhancer binding factor 1 (LEF1).

Conclusions:DCST1-AS1 is activated by MYC and is degraded by binding to miR-873-5p, thereby upregulating the expression of miR-873-5p downstream proteins IGF2BP1, MYC, LEF1 and CD44. MYC, DCST1-AS1 and miR-873-5p form a positive regulatory loop to promote TNBC cell proliferation and metastasis.

CREB1/Lin28/miR-638/VASP Interactive Network Drives the Development of Breast Cancer

Breast cancer is one of the most common malignant tumors worldwide. Metastasis remains the leading cause of death in breast cancer patients. Research on the mechanism of breast cancer metastasis has become a core issue in breast cancer research. Our previous series of studies have shown that VASP, as a key oncogene, plays an important role in the development of various tumors such as breast cancer. In this study, we find that miR-638 can target to inhibit VASP expression, and Lin28 acts as an RNA-binding protein to regulate the processing of miR-638, which inhibits its maturation and promotes the expression of VASP. In addition, we also find that CREB1 acts as a transcription factor that binds to the promoter of Lin28 gene and activates the Lin28/miR-638/VASP pathway. Furthermore, CREB1 can also directly bind to the promoter of VASP, and activate VASP expression, forming a CREB/Lin28/miR-638/VASP interactive network, which plays an important role in promoting cell proliferation and migration in breast cancer. Our study explained the mechanism of CREB1/Lin28/miR-638/VASP network promoting the development of breast cancer, which further elucidated the mechanism of VASP as a key oncogene, and also provided a theoretical basis for expanding new approaches to tumor biotherapy.

Significant Role of MUC1 in Development of Resistance to Currently Existing Anti-cancer Therapeutic Agents

As an extensively glycosylated transmembrane protein of epithelium, Mucin1 (MUC1) mostly protects cells from tensions induced by external milieu. Physiologically, during stress condition, MUC1 separates into MUC1-N and MUC1-C moieties, resulting in transduction of inward survival signals, essential for maintaining cell's functionality. Recent studies have proposed a significant correlation between MUC1 overexpression and amplification of cancer cell's proliferation and metastasis through modulation of multiple signaling pathways and cell-cell and cell-matrix interactions. It has been shown that MUC1- Cytoplasmic Domain (MUC1-CD) accelerates development of resistance to several anti-cancer therapeutic agents including bortezomib, trastuzumab and tamoxifen. Furthermore, MUC1-CD is also involved in promoting expression of multi drug resistance (MDR) genes and finally, silencing MUC1 expression was together with resensitization of human epidermal growth factor receptor 2 positive (HER2+) and/or estrogen receptor (ER+) positive breast cancer cells to bortezomib, trastuzumab and tamoxifen respectively. In this review, we briefly describe the role of MUC1 proto-oncogene in cancer cell's survival, tumor progression and metastasis and then continue with mentioning the mechanisms through which MUC1 induce resistance to various currently existing therapeutic agents in market including bortezomib, trastuzumab and tamoxifen.

HCP5 is a SMAD3-responsive long non-coding RNA that promotes lung adenocarcinoma metastasis via miR-203/SNAI axis

Introduction: Transforming growth factor-beta (TGFβ) signaling plays a vital role in lung adenocarcinoma (LUAD) progression. However, the involvement of TGFβ-regulated long non-coding RNAs (lncRNAs) in metastasis of LUAD remains poorly understood.

Methods: We performed bioinformatic analyses to identify putative lncRNAs regulated by TGF-β/SMAD3 and validated the results by quantitative PCR in LUAD cells. We performed luciferase reporter and chromatin immunoprecipitation assays to demonstrate the transcriptional regulation of the lncRNA histocompatibility leukocyte antigen complex P5 (HCP5) we decided to focus on. Stable HCP5 knockdown and HCP5-overexpressing A549 cell variants were generated respectively, to study HCP5 function and understand its mechanism of action. We also confirmed our findings in mouse xenografts and metastasis models. We analyzed the correlation between the level of lncRNA expression with EGFR, KRAS mutations, smoke state and prognostic of LUAD patients.

Results: We found that the lncRNA HCP5 is induced by TGFβ and transcriptionally regulated by SMAD3, which promotes LUAD tumor growth and metastasis. Moreover, HCP5 is overexpressed in tumor tissues of patients with LUAD, specifically in patients with EGFR and KRAS mutations and current smoker. HCP5 high expression level is positively correlated with poor prognosis of patients with LUAD. Finally, we demonstrated that upregulation of HCP5 increases the expression of Snail and Slug by sponging the microRNA-203 (miR-203) and promoting epithelial-mesenchymal transition (EMT) in LUAD cells.

Conclusions: Our work demonstrates that the lncRNA HCP5 is transcriptionally regulated by SMAD3 and acts as a new regulator in the TGFβ/SMAD signaling pathway. Therefore, HCP5 can serve as a potential therapeutic target in LUAD.

Disseminated nocardiosis with cerebral and subcutaneous lesions on low-dose prednisone

This case report is of a septuagenarian man on chronic low-dose prednisone who presented with disseminated nocardiosis (Nocardia cyriacigeorgica) that was initially mistaken for metastatic brain cancer. Neurologists should be aware of the potential for opportunistic infections with steroid use and to consider a definite tissue diagnosis with culture and histopathology prior to treatment.

Current Challenges of Cancer Anti-angiogenic Therapy and the Promise of Nanotherapeutics

With growing interest in cancer therapeutics, anti-angiogenic therapy has received considerable attention and is widely administered in several types of human cancers. Nonetheless, this type of therapy may induce multiple signaling pathways compared with cytotoxics and lead to worse outcomes in terms of resistance, invasion, metastasis, and overall survival (OS). Moreover, there are important challenges that limit the translation of promising biomarkers into clinical practice to monitor the efficiency of anti-angiogenic therapy. These pitfalls emphasize the urgent need for discovering alternative angiogenic inhibitors that target multiple angiogenic factors or developing a new drug delivery system for the current inhibitors. The great advantages of nanoparticles are their ability to offer effective routes that target the biological system and regulate different vital processes based on their unique features. Limited studies so far have addressed the effectiveness of nanoparticles in the normalization of the delicate balance between stimulating (pro-angiogenic) and inhibiting (anti-angiogenic) factors. In this review, we shed light on tumor vessels and their microenvironment and consider the current directions of anti-angiogenic and nanotherapeutic treatments. To the best of our knowledge, we consider an important effort in the understanding of anti-angiogenic agents (often a small volume of metals, nonmetallic molecules, or polymers) that can control the growth of new vessels.

Overexpression of MICAL2, a novel tumor-promoting factor, accelerates tumor progression through regulating cell proliferation and EMT

Molecule interacting with CasL 2 (MICAL2), a microtubule associated monooxygenase, is involved in cell growth, axon guidance, vesicle trafficking and apoptosis. Recent studies have demonstrated that MICAL2 is highly expressed in tumor and accelerates tumor progression and it is deemed to be a novel tumor-promoting factor. MICAL2 overexpression increases cell proliferation to accelerate tumor growth, and MICAL2 also promotes epithelial-mesenchymal transition (EMT)-related proteins to increase cancer cell metastasis. On mechanism, MICAL2 induces EMT by regulating SRF (serum response factor)/MRTF-A (myocardin related transcription factor A) signaling, Semaphorin/Plexin pathway and inducing ROS (Reactive oxygen species) production. In the present review, we introduced MICAL family, expatiated the structure and functions of MICALs, and summarized the mechanisms of MICAL2 involving tumor progression. The challenges and perspectives for MICAL2 in tumor are also discussed.

Systematic Correlation Analyses of Circulating Tumor Cells with Clinical Variables and Tumor Markers in Lung Cancer Patients

Measurement of circulating tumor cells (CTC) offers promise as a clinical biomarker to monitor disease status, therapeutic response, and progression in cancer patients. However, its clinical value in lung cancer patients has not been fully explored. We systematically evaluate the association of CTCs with clinical variables and tumor markers in a cohort of lung cancer patients. Using the CELLSEARCH System, CTCs were detected in both small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC) patients prior to therapy. Univariate analysis revealed that detection of CTC was related to histology, stage, tumor size, invasiveness, and lymphatic metastasis. CTCs were associated with distant metastases in NSCLC, but not in SCLC. Using multivariate analysis, we found that CTCs were independently correlated with disease stage, SCLC, and elevated serum neuron-specific enolase (NSE). These data suggest that CTCs are more likely to be detected in patients with stage IV disease and with SCLC, and that elevated serum NSE predicts the presence of CTCs.

Activin B Regulates Adhesion, Invasiveness, and Migratory Activities in Oral Cancer: a Potential Biomarker for Metastasis

Activin B, a homodimer of inhibin beta b (INHBB), is a multifunctional cytokine belonging to the transforming growth factor-β (TGF-β) family. However, the molecular functions and clinical relevance of activin B have not been determined in oral cancer. We investigated the critical roles of activin B in oral squamous cell carcinoma (OSCC). We performed quantitative reverse transcriptase-polymerase chain reaction, Western blotting, and immunohistochemistry to study INHBB expression in OSCC-derived cell lines and OSCC clinical samples. The INHBB expression levels were significantly (P < 0.05) overexpressed in OSCCs compared to normal counterparts in vitro and in vivo. Activin B-positivity in OSCC cases was significantly (P < 0.05) correlated with regional lymph node metastasis. The INHBB knockdown (shINHBB) cells promoted cellular adhesion and suppression of cellular invasiveness and migration. After treatment of shINHBB cells with activin B, those activities were restored similar to the shMock cells. In the processes of invasiveness and metastasis, the cells cause epithelial-mesenchymal transition (EMT). TGF-β and its family members are promoters of the EMT process. To investigate whether activin B is related to EMT, we examined the expressions of EMT-related genes and found that INHBB was related closely to EMT. Our results suggested for the first time that activin B indicates tumoral metastasis in OSCCs and might be a useful biomarker for OSCC metastasis.

Down-regulated miR-23a Contributes to the Metastasis of Cutaneous Melanoma by Promoting Autophagy

Melanoma is among the most aggressive tumors, and the occurrence of metastasis leads to a precipitous drop in the patients' survival. Therefore, identification of metastasis-associated biomarkers and therapeutic targets will contribute a lot to improving melanoma theranostics. Recently, microRNAs (miRNAs) have been implicated in modulating cancer invasion and metastasis, and are proved as potential non-invasive biomarkers in sera for various tumors. Here, we reported miR-23a as a novel metastasis-associated miRNA that played a remarkable role in modulating melanoma invasive and metastatic capacity and was of great value in predicting melanoma metastasis and prognosis. We found that serum miR-23a level was significantly down-regulated in metastatic melanoma patients and highly correlated with poor clinical outcomes. In addition, miR-23a level was also remarkably decreased in metastatic melanoma tissues and cell lines. Furthermore, overexpressed miR-23a suppressed the invasive and migratory property of melanoma cells by abrogating autophagy through directly targeting ATG12. Specially, miR-23a-ATG12 axis attenuated melanoma invasion and migration through autophagy-mediated AMPK-RhoA pathway. Finally, the overexpression of miR-23a prevented melanoma metastasis in vivo. Taken together, our findings demonstrate that the metastasis-associated miR-23a is not only a potential biomarker, but also a valuable therapeutic target for melanoma.

Overexpression of PAK1 Correlates with Aberrant Expression of EMT Markers and Poor Prognosis in Non-Small Cell Lung Cancer

Objective: p21-activated kinases (PAKs) are serine/threonine protein kinases. PAK1 and epithelial-mesenchymal transition (EMT) are key therapeutic targets in cancer. The clinical significance of PAK1 and its potential association with EMT phenotype in non-small cell lung cancer (NSCLC) was investigated. Methods: Immunohistochemistry was used to detect the expression of PAK1, and mesenchymal and epithelial markers (vimentin, N-cadherin, and E-cadherin) in 186 cases of NSCLC tissues and 50 cases of tumor-adjacent normal tissues. The correlation of PAK1 with the clinicopathological characteristics, prognosis, and mesenchymal and epithelial markers in NSCLC were analyzed. Results: Compared with the non-tumor tissues, PAK1, vimentin, and N-cadherin levels were markedly elevated in NSCLC tissues, whereas the E-cadherin levels were significantly decreased (P<0.05). The aberrant expression of PAK1 was significantly associated with TNM stage and metastasis (P<0.001). Patients who displayed high expression of PAK1 may achieve a poorer progression-free survival (PFS) and overall survival (OS), compared to those with low expression of PAK1 (P=0.001 and P<0.001). Univariate and multivariate analysis showed that high expression of PAK1 was an independent predictor of poor prognosis [hazard ratio (HR) =2.121, P<0.001, HR=1.928, P=0.001, respectively]. In addition, significant correlations were observed between the EMT markers and OS or PFS (P<0.01). Interestingly, PAK1 expression was positively correlated with vimentin and N-cadherin levels (r=0.473, P<0.001; r=0.526, P<0.001, respectively) and negatively correlated with E-cadherin levels (r=-0.463, P<0.001) in NSCLC tissues. Conclusion: PAK1 may promote NSCLC progression and metastasis through EMT, thereby exhibiting the potential of an efficient prognostic predictor in NSCLC patients.

MiR-93 Promotes Tumorigenesis and Metastasis of Non-Small Cell Lung Cancer Cells by Activating the PI3K/Akt Pathway via Inhibition of LKB1/PTEN/CDKN1A

BACKGROUND

Non-small cell lung cancer (NSCLC) accounts for approximately 85% of clinical lung cancer cases. MicroRNA-93 (miR-93) is an oncomiR in many types of human cancer, exerting pivotal effects in the development and progression of malignancies, including NSCLC. However, the mechanism underlying miR-93 involvement in NSCLC is unknown. Our purpose was to reveal and explain this mechanism, with the goal of contributing to the development of new diagnostic biomarkers and individualized therapeutic tools.

METHODS

The expression of miR-93 was determined in NSCLC cell lines A549, H1975, and H1299. The cells were transfected with control plasmids (Mock group), miR-93 overexpression plasmids (miR-93 Up group), or miR-93 inhibitor plasmids (miR-93 Down group) to generate stable miR-93-overexpressing or -depleted cells. The effects of miR-93 on proliferation, migration, and invasion of these cells were determined. The in vivo effects of miR-93 on tumor metastasis were determined in an NSCLC xenograft mouse model. The molecular mechanisms underlying these effects were investigated via dual luciferase reporter assay and western blotting.

RESULTS

MiR-93 expression levels were significantly greater in the NSCLC cell lines than in normal lung epithelial cells. Cell proliferation, migration, and invasion were significantly stimulated by miR-93 upregulation (all P<0.05) and inhibited by miR-93 downregulation. Dual luciferase reporter assay demonstrated that miR-93 directly bound with the 3'-untranslated region of the tumor suppressor gene LKB1. Western blotting analysis indicated that miR-93 activated the PI3K/Akt pathway by inhibiting LKB1, PTEN, and p21. Increased expression of miR-93 induced significant hepatic metastasis of lung cancer in the xenograft mouse model.

CONCLUSION

Overexpression of miR-93 facilitates tumorigenesis and metastasis of NSCLC. These findings provide novel insight into the mechanism of miR-93 involvement in NSCLC, suggesting that miR-93 may serve as a potential therapeutic target.

Breast Cancer Malignant Processes are Regulated by Pax-5 Through the Disruption of FAK Signaling Pathways

The study of genetic factors regulating breast cancer malignancy is a top priority to mitigate the morbidity and mortality associated with this disease. One of these factors, Pax-5, modulates cancer aggressiveness through the regulation of various components of the epithelial to mesenchymal transitioning (EMT) process. We have previously reported that Pax-5 expression profiles in cancer tissues inversely correlate with those of the Focal Adhesion Kinase (FAK), a potent activator of breast cancer malignancy. In this study, we set out to elucidate the molecular and regulatory relationship between Pax-5 and FAK in breast cancer processes. Interestingly, we found that Pax-5 mediated suppression of breast cancer cell migration is dependent of FAK activity. Our mechanistic examination revealed that Pax-5 inhibits FAK expression and activation. We also demonstrate that Pax-5 is a potent modulator of FAK repressors (p53 and miR-135b) and activator (NFκB) which results in the overall suppression of FAK-mediated signaling cascades. Altogether, our findings bring more insight to the molecular triggers regulating phenotypic transitioning process and signaling cascades leading to breast cancer progression.

MicroRNA-34c Suppresses Breast Cancer Migration and Invasion by Targeting GIT1

Abnormal expression of microRNAs plays important role in tumor metastasis. Migration and invasion of cancer cells accord for the metastasis and deterioration of breast cancer. However, the regulatory role of microRNAs in the invasion and migration of breast cancer cells has not completely understood yet. Here we found that microRNA-34c (miR-34c) was significantly downregulated in metastatic tissue of breast cancer. In vitro study showed that miR-34c negatively regulated GIT1 protein expression by binding to the 3'UTR of GIT1 mRNA. Consistently, GIT1 protein expression was found upregulated significantly in metastatic breast cancer. Moreover, miR-34c overexpression suppressed the expression of GIT1 protein, and this effect was restored by AMO-miR-34c in breast cancer cells. Overexpression of miR-34c suppressed cell migration and invasion in both MCF-7 and MDA-MD-231 breast cancer cells. Furthermore, knockdown of endogenous GIT1 expression reduced the migration and invasion of both two breast cancer cells. Collectively, miR-34c downregulation in breast cancer cells resulted in the upregulation of GIT1, which in turn enhanced the migration and invasion of breast cancer. This study highlights molecular mechanism of migration and invasion of breast cancer cells.

Rho GTPase RhoJ is Associated with Gastric Cancer Progression and Metastasis

Rho GTPases play a pivotal role in tumor progression by regulating tumor cell migration and invasion. However, the role of Rho GTPases in gastric cancer (GC) remains unexplored. This study aimed to investigate the clinical implications of RhoJ, which is an uncharted member of Rho family. RhoJ expression in human GC cell lines and surgical specimens from GC patients were analyzed. Moreover, in vitro gain-of-function analysis was performed to evaluate the malignant phenotypes of RhoJ-overexpressing GC cells. The extent of RhoJ expression varied among GC cell lines and GC patients. YCC-9 cell line displayed the strongest expression, while YCC-10, -11, and -16 showed scant expressions. Of the 70 GC patients, 34 (48.6%) had RhoJ expression in their GC tissue, and patients with high RhoJ expression had more diffuse type GC (73.5% vs. 41.7%), were at more advanced stages (stage III, IV: 85.3% vs. 58.4%), and had more frequent metastasis (47.1% vs. 11.1%), denoting that RhoJ has a potential role in GC progression and metastasis. High RhoJ expression significantly correlated with poor overall survival and recurrence-free survival after surgical resection of gastric cancer. Finally, In vitro gain-of-function experiments showed 41.3% enhanced motility and 60.4% enhanced invasiveness in RhoJ-overexpressing GC cells compared to control, with negligible difference in cell proliferation. Collectively, high RhoJ expression is an independent negative prognostic factor for the survival outcome of GC and correlated with the increased cell motility and invasiveness.

A Point Mutation in DNA Polymerase β (POLB) Gene Is Associated with Increased Progesterone Receptor (PR) Expression and Intraperitoneal Metastasis in Gastric Cancer

Increased expression of progesterone receptor (PR) has been reported in gastric cancer (GC). We have previously identified a functional T889C point mutation in DNA polymerase beta (POLB), a DNA repair gene in GC. To provide a detailed analysis of molecular changes associated with the mutation, human cDNA microarrays focusing on 18 signal transduction pathways were used to analyze differential gene expression profiles between GC tissues with T889C mutant in POLB gene and those with wild type. Among the differentially expressed genes, notably, PR was one of the significantly up-regulated genes in T889C mutant POLB tissues, which were subsequently confirmed in POLB gene transfected AGS cell line. Interestingly, patients with T889C mutation and PR positivity were associated with higher incidence of intraperitoneal metastasis (IM). In vitro studies indicate that PR expression was upregulated in AGS cell line when transfected with T889C mutant expression vector. Cotransfection of T889C mutant allele and PR gene induced cell migration in the cell line. These data demonstrated that T889C mutation-associated PR overexpression results in increased IM. Therefore, T889C mutation-associated PR overexpression may serve as a biomarker for an adverse prognosis for human GC.

Expression of SRSF3 is Correlated with Carcinogenesis and Progression of Oral Squamous Cell Carcinoma

OBJECTIVE

Oral squamous cell carcinoma (OSCC) is the most common malignancy of head and neck with high mortality rates. The mechanisms of initiation and development of OSCC remain largely unknown. Dysregulated alternative splicing of pre-mRNA has been associated with OSCC. Splicing factor SRSF3 is a proto-oncogene and overexpressed in multiple cancers. The aim of this study was to uncover the relationship between SRSF3 and carcinogenesis and progression of oral squamous cell carcinoma.

DESIGN AND METHODS

The expression of SRSF3 in oral normal, dysplasia, or carcinoma tissues was analyzed by immunohistochemistry. The expression levels of EMT-related genes were quantified by real-time quantitative RT-PCR. The expression of SRSF3 in DMBA treated primary cultured oral epithelial cells were analyzed by western blot.

RESULT

SRSF3 is overexpressed in oral cancer and moderate or severe dysplasia tissues. Patients with high grade cancer or lymphatic metastasis showed up-regulated expression of SRSF3. Knockdown of SRSF3 repressed the expression of Snail and N-cadherin in vitro. Carcinogen DMBA treated primary cultured oral epithelial cells showed significantly increased SRSF3 level than in control cells.

CONCLUSION

Our results suggested that SRSF3 is associated with the initiation and development of OSCC and may be a biomarker and therapeutic target of OSCC.

Long non-coding RNA MEG3 suppresses migration and invasion of thyroid carcinoma by targeting of Rac1

Thyroid cancer, the most common primary endocrine malignancy in adult, imperatively requires new therapeutic studies that could target the molecular regulatory mechanism. Even though emerging evidence showed that long noncoding RNAs (Lnc-RNAs) are involved in different biological characteristic of malignant tumor, such as cell growth and apoptosis as well as cancer progression and metastasis. Limited data are available on the function of Lnc-RNAs in thyroid cancer invasion and metastasis. Among the 5 tested lnc-RNAs , the present study demonstrates that MEG3 was significantly down-regulated in papillary thyroid carcinoma (PTC) tissues with lymph-node metastasis than in primary thyroid cancer. Moreover, the down- regulated MEG3 was associated with lymph-node metastasis. Over-expression of MEG3 could strongly inhibit the cell migration and invasion in TPC-1 and HTH83 thyroid cancer cell lines. In addition, we also showed that Rac1 was negatively regulated by lncRNA-MEG3 at the posttranscriptional level, via a specific target site within the 3΄UTR by dual luciferase reporter assay. The expression of Rac1 was inversely correlated with lncRNA-MEG3 expression in PTC tissues. Thus, this study suggests that MEG3 acts as novel suppressor of migration and invasion by targeting Rac1 gene.

Long Noncoding RNA: its partners and their roles in cancer

RNA transcripts, which do not encode proteins, have received considerable attention in recent years. These non-coding RNAs are classified into two groups: small non-coding RNAs and long non-coding RNAs (lncRNAs). Increasing evidence suggests that lncRNAs are emerging as key regulators in many biological processes. However, knowledge of the underlying mechanisms whereby they act is still limited. Here, we try to elucidate the way that lncRNAs function in the context of DNA, RNA and protein interaction networks. It is noteworthy that lncRNA and another type of non-coding RNA microRNA (miRNA) may 'talk' to each other more frequently than ever expected. Additionally, lncRNAs display aberrant expression profiles in different kinds of cancers, with their potential roles in carcinogenesis and cancer metastasis. We summarize the effect of some cancer related lncRNAs upon tumor biological events, including cell proliferation, apoptosis, invasion and metastasis. Finally, we focus on the clinical value of lncRNAs, considering their potential application in cancer diagnosis, prognosis and therapeutic intervention.

Down-regulated long non-coding RNA H19 inhibits carcinogenesis of renal cell carcinoma

Long non-coding RNAs (lncRNAs) have been shown to have important regulatory roles in cancer biology. LncRNA H19 has been recently shown to be upregulated and play important roles in several cancers such as breast cancer, bladder cancer, and gastric cancer. However, the role of H19 in clear cell renal carcinoma (ccRCC) remains largely unknown.The expression levels of lncRNA H19 in ccRCC tissues and renal cancer cell lines were evaluated by quantitative Real-time PCR (qRT-PCR). And its association with overall survival of patients was analyzed by statistical analysis. Small interfering RNA (siRNA) was used to suppress H19 expression in renal cancer cell lines. In vitro assays were performed to further explore its role in tumor progression.The relative level of H19 was significantly higher in ccRCC compared to the adjacent normal renal tissues. And higher expression of H19 was found in renal cancer cells compared to the nonmalignant renal cells HK-2. Furthermore, The ccRCC patients with higher H19 expression had more advanced clinical stage and poorer prognosis than those with lower expression, Kaplan-Meier analysis revealed that patients with higher H19 expression had a poorer overall survival and H19 expression could be an independent prognostic marker for ccRCC patient. The results of in vitro assays indicated that knockdown of H19 reduced cell proliferation, invasion, and migration. Our data suggested that lncRNA H19 might be considered as a potential prognostic indicator and a target for gene therapy of ccRCC.

Microtubule-associated protein Mdp3 promotes breast cancer growth and metastasis

Breast cancer is the most prevalent cancer in women worldwide with a high mortality rate, and the identification of new biomarkers and targets for this disease is greatly needed. Here we present evidence that microtubule-associated protein (MAP) 7 domain-containing protein 3 (Mdp3) is highly expressed in clinical samples and cell lines of breast cancer. The expression of Mdp3 correlates with clinicopathological parameters indicating breast cancer malignancy. In addition, Mdp3 promotes breast cancer cell proliferation and motility in vitro and stimulates breast cancer growth and metastasis in mice. Mechanistic studies reveal that γ-tubulin interacts with and recruits Mdp3 to the centrosome and that the centrosomal localization of Mdp3 is required for its activity to promote breast cancer cell proliferation and motility. These findings suggest a critical role for Mdp3 in the growth and metastasis of breast cancer and may have important implications for the management of this disease.

FGF10: Type III Epithelial Mesenchymal Transition and Invasion in Breast Cancer Cell Lines

Purpose: Fibroblastic growth factor-10 (FGF-10) has an important role in type I epithelial mesenchymal transition (EMT) during the embryonic period of life (gastrulation). Since EMT has a critical role during cancer cells invasion and metastasis (type III) this study sought to investigate the possible role of FGF-10 in type III EMT by monitoring breast cancer cell lines' behavior by FGF-10 regulation.

Methods: MCF-7 and MDA-MB-231 cell lines with different levels of FGF10 expression were treated with FGF-10 recombinant protein and FGF-10 siRNA, respectively.

Results: The cell viability, migration, colony formation and wound healing have a direct relationship with FGF-10 expression, while FGF-10 expression decreased apoptosis. All mesenchymal factors (such as vimentin, N cadherin, snail, slug, TGF-β) increased due to FGF-10 expression with contrary expression of epithelial markers (such as E-cadherin). Moreover, GSK3β phosphorylation (inactivation) increased with FGF-10 expression.

Conclusion: The important role of FGF-10 in type III EMT on cancer cells and initiation of metastasis via various kinds of signaling pathways has been suggested.

Regulation of Desmocollin3 Expression by Promoter Hypermethylation is Associated with Advanced Esophageal Adenocarcinomas

BACKGROUND: Desmocollin3 (DSC3) is a member of the cadherin superfamily of calcium-dependent cell adhesion molecules and plays an important role in tumor invasion and metastasis. In this study, we investigated the epigenetic mechanism that regulates DSC3 expression in esophageal adenocarcinomas (EACs). METHODS: Expression of DSC3 was analyzed by quantitative real-time polymerase chain reaction (qRT-PCR). The promoter DNA methylation level of DSC3 was examined using quantitative bisulfite pyrosequencing. RESULTS: The qRT-PCR analysis demonstrated significant down-regulation of the DSC3 mRNA levels in human EAC cell lines and tissue samples (P<.001). In addition, the EAC cell lines and tumor samples have aberrant promoter hypermethylation as compared to normal esophageal samples (P<.001). DSC3 promoter hypermethylation (>10% methylation level) was detected in 97.5% (39/40) of EAC samples whereas none of the normal tissue samples showed hypermethylation (P<.0001). There was a significant inverse correlation between promoter DNA methylation levels and mRNA expression folds for DSC3 (coefficient r=-0.685, P<.0001). Treatment of FLO-1 and SKGT4 EAC cells with 5-Aza-deoxytidine led to a significant reduction in the promoter DNA methylation levels with restoration of the DSC3 expression, suggesting that promoter DNA methylation is a key epigenetic mechanism regulating DSC3 expression. High DSC3 promoter DNA methylation levels were significantly correlated with advanced tumor stage (P<.001) and lymph node metastasis (P<.001). CONCLUSION: Taken together, our results demonstrate that epigenetic silencing of DSC3 is a frequent finding in EAC that is possibly associated with advanced stages.

Osteopontin splice variants differentially exert clinicopathological features and biological functions in gastric cancer

Purpose: Gastric cancer (GC) remains a leading cause of death worldwide, and an elevated expression of osteopontin (OPN) may correlate with its poor survival. Alternative splicing of OPN can result in three isoforms, OPN-a, OPN-b and OPN-c. The aim of our current study is to examine the expression pattern and biological functions of OPN splice variants in GC.

Methods: Firstly, we evaluated the expression of OPN splice variants in 7 gastric cell lines, 101 pairs of GC tissues and their adjacent non-tumor tissues by Quantative real-time PCR (QT-PCR). Gain-of-function experiments were subsequently performed to determine their diverse roles in malignant behaviors of GC. Besides, their differential effects on the regulation of crucial downstream molecules were further explored in the anti-apoptotic and pro-metastatic process.

Results: We found that OPN-b is the dominant kind of OPN isoform in GC cell lines. Although the expression levels of three variants were all elevated in GC tissues, increased OPN-b or OPN-c expression could correlate with clinicopathological features. Functional analyses further showed that OPN-b most strongly promoted GC cell survival possibly by regulation of Bcl-2 family proteins and CD44v expressions. Moreover, OPN-c most effectively stimulated GC metastatic activity by increasing secretion of MMP-2, uPa, and IL-8.

Conclusions: Our results suggest that OPN splice variants differentially exert clinicopathological features and biological functions in GC. Therefore, focusing on specific OPN isoform could be a novel direction for developing diagnostic and therapeutic approaches in GC.

Mucoepidermoid carcinoma - unknown primary and late distant metastasis: an unusual course of the disease

The authors report the case to understand this unusual presentation and prognosis of mucoepidermoid carcinoma following treatment. We present a case of mucoepidermoid carcinoma in a 67-year-old man. The cancer was diagnosed in the right side of his neck but the primary tumor remained unknown despite attempts at staging. The neck was treated successfully and followed up for 2 years. Metastasis of the primary lesion to the left triceps was diagnosed following a swelling noticed by the patient during the 2-year follow up period. Mucoepidermoid carcinoma can be a low, intermediate or high-grade malignancy and can metastasize to different parts of the body. However, this is the first case report of a metastasis to the triceps muscle.

An Underrated Potential Risk of Bronchiectasis: Lymph Node Metastasis of a Pulmonary Tumorlet

Pulmonary tumorlets occur as the result of extensive scar caused by bronchiectasis or other inflammatory processes. They are minute lesions found in close association with the bronchioles and may rarely metastasize to lymph nodes. We present a 35-year-old male patient who underwent bilobectomy inferior with a diagnosis of bronchiectasis of 20 years duration. Histologic examination showed cystic bronchiectasis with areas of multiple neuro-endocrine tumor-lets in addition to metastatic peribronchial lymph nodes. We emphasize the significance of early surgical treatment of bronchiectasis showing little to no response to medical therapy as well as peribronchial lymph node dissection.