Detection of cancer stem cells by EMT-specific biomarker-based peptide ligands

The occurrence of epithelial-mesenchymal transition (EMT) within tumors, which enables invasion and metastasis, is linked to cancer stem cells (CSCs) with drug and radiation resistance. We used two specific peptides, F7 and SP peptides, to detect EMT derived cells or CSCs. Human tongue squamous carcinoma cell line-SAS transfected with reporter genes was generated and followed by spheroid culture. A small molecule inhibitor-Unc0642 and low-dose ionizing radiation (IR) were used for induction of EMT. Confocal microscopic imaging and fluorescence-activated cell sorting analysis were performed to evaluate the binding ability and specificity of peptides. A SAS xenograft mouse model with EMT induction was established for assessing the binding affinity of peptides. The results showed that F7 and SP peptides not only specifically penetrated into cytoplasm of SAS cells but also bound to EMT derived cells and CSCs with high nucleolin and vimentin expression. In addition, the expression of CSC marker and the binding of peptides were increased in tumors isolated from Unc0642/IR-treated groups. Our study demonstrates the potential of these peptides for detecting EMT derived cells or CSCs and might provide an alternative isolation method for these subpopulations within the tumor in the future.

Mucoadhesive film containing α-mangostin shows potential role in oral cancer treatment

Background Oral cancer is often preceded by a mucosal lesion called an oral potentially malignant disorder (OPMD). Many plant-derived compounds are of value in medicine. The objectives of this study were to develop a soluble mucoadhesive film containing α-mangostin (α-MG), a compound extracted from the peel of mangosteen fruit, and determine its activities against oral cancer cells, against human papillomavirus type 16 (HPV-16) pseudovirus, and its anti-inflammatory properties. Methods A soluble mucoadhesive film containing α-MG was prepared. Oral squamous carcinoma cell line (SCC25), murine macrophage cells (RAW264.7), and human gingival fibroblast cell line were cultured. Anticancer activity and viability of SCC25 cells in response to α-MG film solution were determined by MTT assay. HPV-16 pseudovirus was constructed and effects of the film solution on attachment and post-attachment steps of the infection were investigated. Anti-inflammatory activity was assessed by nitric oxide (NO) inhibition. Fibroblast cell migration was determined by in vitro scratch assay. Results The soluble α-MG film showed cytotoxic effects on SCC25 cells in concentration > 125 µg/ml with IC50 of 152.5 µg/ml. Antiviral activity against HPV-16 pseudovirus was observed at attachment step, but not at post-attachment step. The film also possessed a strong anti-inflammatory effect and promoted wound healing without cytotoxicity. Conclusions Mucoadhesive film containing α-MG has a cytotoxic effect on oral squamous carcinoma cell line and an inhibitory effect on HPV-16 pseudovirus at attachment step. The α-MG film also shows a potent anti-inflammatory activity and enhances wound healing. Thus, the soluble α-MG film may have a potential role in treating oral cancer.

Carvacrol Induces Cell Apoptosis in Human Esophageal Squamous Carcinoma the Human Esophageal Squamous Carcinoma Cell Line (KYSE-150) Cells

Carvacrol is a natural phenol with antioxidant, antimicrobials, and anti-cancer activities. The present study aimed to explore the anti-cancer activity of carvacrol in human esophageal squamous carcinoma KYSE-150 cells. Cell proliferation and apoptosis were measured using WST-1 assay and cell death detection ELISA kit respectively. Caspase activities were determined with caspase fluorometric assay kits. WST-1 assay revealed that carvacrol suppressed KYSE-150 cell proliferation in both dose and time-dependent manner. Carvacrol could increase cell apoptosis in a dose-dependent manner through caspase-3 and caspase-9 activation. In addition, Bcl-2 mRNA levels were significantly decreased by carvacrol treatment. This study delivers that carvacrol exerts a favorable anti-cancer action against esophageal cancer via inhibiting cell proliferation and inducing cell apoptosis. These discoveries suggest that carvacrol is deserved to be further studied and developed as a chemotherapeutic agent for esophageal cancer.

The Role of the Hematopoietic Cell-Specific Protein 1-Associated Protein X-1 in Human Papillomavirus 16 E2-Induced Human Cervical Squamous Carcinoma Cell Apoptosis via a Mitochondria-Dependent Pathway

<b><i>Objectives:</i></b> Human papillomavirus 16 (HPV 16) E2 is a transcriptional regulator that plays a key role in regulating a variety of biological responses. Hematopoietic cell-specific protein 1-related protein X-1 (HAX-1) is a mitochondrial membrane protein, and the HAX-1 gene is involved in the occurrence, growth, invasion, and metastasis of various human malignant tumors. The purpose of this study was to investigate the relationships among HPV 16 E2, the role of HAX-1 gene, and the underlying intracellular apoptotic mechanism of human cervical squamous carcinoma cells (C33a and SiHa). <b><i>Methods:</i></b> In this study, HAX-1 expression was examined using real-time polymerase chain reaction, Western blot, and immunohistochemical staining analysis. Apoptosis of cells was assessed by flow cytometry. The mitochondrial function was assessed by the mitochondrial copy number, reactive oxygen species (ROS) generation, the mitochondrial membrane potential (ΔΨm), and mitochondrial morphology. <b><i>Results:</i></b> Our study demonstrated that the expression of the HAX-1 gene was significantly increased in human cervical carcinoma tissues relative to noncancerous cervix tissues. HPV 16 E2 inhibited HAX-1 protein expression. Overexpression of HAX-1 increased the mitochondrial copy number, decreased the production of ROS, and maintained the integrity of the mitochondrial membrane and morphology. So, enhanced expression of the HAX-1 gene could abrogate the HPV 16 E2-induced cell apoptosis. <b><i>Conclusion:</i></b> Therefore, these data support a mechanism that HAX-1 plays a crucial role in HPV 16 E2-induced human cervical squamous carcinoma cell apoptosis in a mitochondrial-dependent manner.

Assessment of MicroRNA (miR)-365 Effects on Oral Squamous Carcinoma Cell Line Phenotypes

miR-365 is a microRNA that regulates transcription and has been demonstrated to promote oncogenesis and metastasis in some cancers while suppressing these effects in others. Virtually no information is known about the presence or function of miR-365 in oral cancers. Based upon this information, the primary goal of this project was to evaluate the expression of miR-365 in existing oral cancer cell lines. Five commercially available oral cancer cell lines (SCC4, SCC9, SCC15, SCC25, and CAL27) were obtained and cultured. RNA was then screened by PCR using primers specific for miR-365, as well as matrix metalloproteinase (MMP-2) and a downstream cancer stem cell regulator (NKX2.1), and structural and metabolic standards (beta actin, GAPDH). miR-365 was detected among these oral cancers, and some cells also expressed NKX2.1 and MMP-2, which correlated with miR-365 levels. The relative expression of miR-365, NKX2.1, and MMP-2 RNA was higher than expected. Transfection of miR-365 resulted in a significant increase in proliferation, which was not observed in the negative controls. These data appear to confirm miR-365 expression in oral cancers, which may also be correlated with MMP-2 and NKX2.1 expression. Moreover, the fastest growing oral cancers with the highest viability produced the most miR-365. In addition, miR-365 transfected into cells significantly increased growth, even in normal cells. More research is needed to elucidate the pathways responsible for these observations.

Synergistic anti-cancer activity of combined 5-fuorouracil and gallic acid-stearylamine conjugate in A431 human squamous carcinoma cell line

Purpose: To evaluate the individual and synergistic anti-cancer effects of 5-fuorouracil (5-FU) and synthesized gallic acid-stearylamine (GA-SA) conjugate in A431 human squamous cancer cell line. Methods: Characterisation of the synthesised conjugate was performed using Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), and mass spectrometry (MS). The synergistic effect of the combination therapy (5-FU/GA-SA) was assessed by determining their inhibitory concentration (IC30) whereby A431 cells were treated with 5-FU:GA–SA conjugate at various ratios ranging from 5:1 to 1:5. Results: The cytotoxicity of 5-FU was 29 %, while that of the combination of 5-FU with GA–SA conjugate was as high as 60 %. Thus, this combination showed significant synergistic enhancement in cytotoxicity (p < 0.05). The results obtained also revealed that the IC30 values of 5-FU and the GA–SA conjugate were 1 and 10 µg/mL, respectively. The IC30 values of the combination ratios indicated that the dosages used in the study were safe in HaCaT normal cell line. Conclusion: These results indicate that 5-FU/GA–SA conjugate at a ratio of 1:1 is effective against A431 cell line (cancer cells)) but safe in HaCaT cell lines (normal cells).