HOXA10Homeobox Gene Regulates The Cell Cycle In Endometrial Cancer

Endometrial cancer is the fourth leading cause of cancer death in women and itsmolecular pathogenesis remains unclear， Homeobox genes （HOX） constitute asuperfamily of genes that control cell differentiation and morphogenesis duringembryonic development. These “master-regulatory” genes are characterized by thepresence of a signature DNA sequence that contains180bp nucleotide known as thehomeodomain. Homeobox genes are highly conserved throughout evolution and arecategorized into several families. The human homeobox genes contain at least39member, divided into A, B, C, D four clusters, in female，HOXA9，HOXA10，HOXA11 could regulate Mullerian ducts differentiation and morphogenesis to fallopian tube,uterus and cervix respectively. In normal menstrual cycle, HOXA10gene has a vitalfunction in regulating the endometrium proliferation, secretion and stripping. Inresent years, there are numerous examples of aberrant HOX genes expression incancer. We previously reported that expression of HOXA10gene decreased inendometrial cancer, enhanced HOXA10gene expression can inhibit cell invasion inendometrial cancer cell.Cell cycle event is one of the most important research aspects in cell biology.Loss the ability of cell cycle arrest and acquire unlimited proliferative capacity whichis the characteristics of the rapid progression of the cancer cell. Many studies haveshown that abnormal cell cycle-related protein expression is associated withtumorigenesis. The molecular mechanisms of regulation these genes have also beenthe hot research areas in oncology. As an inhibiting factor of CDKs, p21has beenextensively studied. Previous studies demonstrated that expression of p21genedecreased in endometrial cancer. It’s unclear that whether there has correlationbetween expression of HOXA10and p21gene, HOXA10could regulate the cell cycleand p21gene expression in endometrial cancer.Therefore, we prepared to detect the expression of HOXA10and p21gene inendometrial cancer, correlation analysis was analyzed by Pearson correlation. wetransfection HOXA10expression plasmid and HOXA10-siRNA to endometrial cancercells, up or down regulate HOXA10expression in endometrial cancer cell, exploredHOXA10gene regulate the cell cycle and p21gene expression, To elucidate themolecular mechanism of HOXA10regulate the development of endometrial cancerand provide the theoretical basis for biological targeted therapy. Part I The role of HOXA10and p21gene inendometrial cancerObjective: The aim of this study was to demonstrate the expression of HOXA10（homeobox gene） and p21gene in endometrial cancer and normalendometrium. Investigate the expression of HOXA10gene and p21gene in endometrial cancer.Methods: Extracted total RNA and total protein from endometrial cancer andnormal endometrium tissues, we used reversetranscription-Polymerase chain reaction,（RT-PCR） and Real-Timepolymerase chain reaction （Real-Time PCR） to detected theexpression of HOXA10and p21gene mRNA in normalendometrium and endometrial cancer. Expression of HOXA10protein in normal endometrium and endometrial cancer was detectedby western blot. the expression correlation between HOXA10andp21gene was analyzed by Pearson correlation.Results: Compared with normal endometrium, expression of HOXA10decreased in endometrial cancer （p<0.05）. With the increased cancergrade, HOXA10protein expression significantly reduced. Expressionof p21gene decreased in endometrial cancer （p<0.05）. There havepositive correlation between the expression of HOXA10and p21gene in normal endometrium and endometrial cancer （r=0.4445,p<0.05） Conclusions: Expression of HOXA10and p21gene decreased in endometrialcancer. With the increased cancer grade, HOXA10proteinexpression significantly reduced. There have positive correlationbetween the expression of HOXA10and p21gene in normalendometrium and endometrial cancer. Part II HOXA10homeobox gene regulates the cell cycleand the expression of p21^WAF1/CIP1genein endometrial cancerObjective: The aim of this study was to investigate HOXA10gene regulates thecell cycle and p21gene expression in endometrial cancer cell lines（ishikawa, KLE）Methods:1.We subcloned HOXA10CDS （by standard PCR） into the pCDNA3.1（+） to generate the HOXA10-pCDNA3.1plasmid2. We transfected HOXA10plasmid into endometrial cancer cell lines.RT-PCR、 Real-Time PCR and Western Blot was used todemonstrate p21gene expression after enforce expression ofHOXA10gene in endometrial cancer cell. FCM detected cell cyclechange.3. We used small interfering RNA （siRNA） technology to interfere the expression of HOXA10in endometrial cancer cells. RT-PCR、Real-Time PCR and Western Blot was used to demonstrate p21gene expression after knockdown expression of HOXA10gene inendometrial cancer cell.Results:1. the results of Gene sequencing showed that HOXA10generecombination plasmid was successfully constructed; HOXA10generecombination plasmid could accurate transcription in the cell,translation of HOXA10mRNA and protein.2. Enforcing HOXA10expression in endometrial cancer cell couldinducing cell cycle arrested in G1phase and upregulate p21genemRNA and protein3. P21gene mRNA and protein was down regulated after knockdownthe expression HOXA10in endometrial cancer cellConclusions: HOXA10gene could regulate cell cycle and p21gene expression inendometrial cancer...