Small-interfering RNA-mediated silencing of the MAPK p42 gene induces dual effects in HeLa cells

Role of the tumour protein P53 gene in human cervical squamous carcinoma cells: Discussing haematopoietic cell-specific protein 1-associated protein X-1-induced survival, migration and proliferation

The haematopoietic cell-specific protein 1-associated protein X-1 (HAX-1), as a mitochondrial membrane protein, induces cancer progression and metastasis. The present study aimed to investigate the role of HAX-1-induced survival, migration and proliferation of human cervical squamous carcinoma cells and to elucidate its potential molecular mechanisms. The level of HAX-1 was examined by quantitative polymerase chain reaction and western blot analyses. The survival, migration and proliferation of the human cervical squamous carcinoma SiHa cell line were measured by the water-soluble tetrazolium salt (WST-1) assay, Transwell assay and ³H-thymidine incorporation into DNA (³H-TdR) assay, respectively. The intracellular reactive oxygen species (ROS) was estimated by the fluorescence of H₂DCFDA, and the mitochondrial membrane potential was tested using a JC-1 probe. The expression of the HAX-1 gene was significantly increased in human cervical carcinoma tissues relative to non-cancerous cervix tissues. Overexpression of HAX-1 increased the survival, migration and proliferation ability of SiHa cells, decreased the production of ROS, and maintained the integrity of the mitochondrial membrane and morphology. The effect brought on these cells could be abrogated by the addition of wild-type tumour protein P53 (p53) or carbonyl cyanide-p-trifluoro methoxyphenylhydrazone-induced mitochondrial dysfunction. In summary, these data support the notion that HAX-1 induced the survival, migration and proliferation of human cervical squamous carcinoma cells by inhibiting its downstream regulatory factor p53 in SiHa cells.

Cervical cancer stem-like cells: systematic review and identification of reference genes for gene expression

Cervical cancer is the fourth most common cancer affecting women worldwide. Among many factors, the presence of cancer stem cells, a subpopulation of cells inside the tumor, has been associated with a worse prognosis. Considering the importance of gene expression studies to understand the biology of cervical cancer stem cells (CCSC), this work identifies stable reference genes for cervical cancer cell lines SiHa, HeLa, and ME180 as well as their respective cancer stem-like cells. A literature review was performed to identify validated reference genes currently used to normalize RT-qPCR data in cervical cancer cell lines. Then, cell lines were cultured in regular monolayer or in a condition that favors tumor sphere formation. RT-qPCR was performed using five reference genes: ACTB, B2M, GAPDH, HPRT1, and TBP. Stability was assessed to validate the selected genes as suitable reference genes. The evaluation validated B2M, GAPDH, HPRT1, and TBP in these experimental conditions. Among them, GAPDH and TBP presented the lowest variability according to the analysis by Normfinder, Bestkeeper, and ΔCq methods, being therefore the most adequate genes to normalize the combination of all samples. These results suggest that B2M, GAPDH, HPRT1, and TBP are suitable reference genes to normalize RT-qPCR data of established cervical cancer cell lines SiHa, HeLa, and ME180 as well as their derived cancer stem-like cells. Indeed, GAPDH and TBP seem to be the most convenient choices for studying gene expression in these cells in monolayers or spheres.

Recent advances in molecular biology and treatment strategies for intracranial germ cell tumors

BACKGROUND

Intracranial germ cell tumors (IGCTs) are a group of rare pediatric brain tumors which include various subtypes. The current understanding of the etiology of the tumors and their optimal management strategies remain controversial.

DATA SOURCES

The data on IGCTs were collected from articles published in the past 20 years, and the origin and etiology of IGCTs at molecular level as well as the relative roles of varied treatment strategies in different prognosis groups according to Matsutani's classification were reviewed.

RESULTS

Recent cellular and molecular evidence suggests that IGCTs may arise from the transformation of endogenous brain cells; and findings in the molecular characterization of IGCTs suggest roles of CCND2, RB1, and PRDM14 in the pathogenesis of IGCTs and identify the KIT/RAS and AKT1/mTOR pathways as potential therapeutic targets in future. According to Matsutani's classification of IGCTs, the good prognosis group includes both germinomas and mature teratomas. For germinomas, both radiation alone and reduced-dose radiotherapy in combination with adjuvant chemotherapy are effective, while complete surgical excision is recommended for mature teratomas. In the intermediate prognosis group, immature teratoma has been successfully treated with gamma knife surgery. However, for intermediate prognosis IGCTs other than immature teratomas, gross total resection with adjuvant chemotherapy and radiotherapy or gamma knife surgery may be necessary to achieve cure. In the poor prognosis group, survival outcomes are unsatisfactory, and complete surgical resection combined with more intensive chemotherapy and radiotherapy remains the best available treatment option at this time.

CONCLUSIONS

IGCTs should be strictly classified according to their pathological categories before administering pathology-specific treatments. Although open microsurgical excision is the traditional surgical strategy for IGCTs, recent publications also support the role of endoscopic surgical options for pineal region IGCTs.