Objective To establish human lung adenocarcinoma multidrug resistance cell lines in vitro,observe their biological characteristics,and investigate the mRNA expressions of DNA pol?,mdr 1,mrp1,GST-?,lrp and topo Ⅱ genes.Methods Paclitaxel-resistant cell lines(A549/TXL20) were established in vitro by exposure to stepwise increased concentrations of the drug in a cell culture medium.Biological morphology and cell cycles were analyzed by morphometry and flow cytometry.The chemoresistance indexes of cells were measured by methyl tetrazolium assay.Evaluation of growth and in vitro drug sensitivity were performed.RT-PCR was employed to analyze the mRNA expressions of the DNA pol?,mdr 1,mrp1,GST-?,lrp,and topo Ⅱ genes.Results ① Compared with parent cells,the resistant sublines had a lower confluent density.They were smaller and mixed with giant cells in different sizes and with different numbers of nucleoli,and the growth property of A549/TXL20 did not change significantly compared with A549 cell lines.② The resistant cells,A549/TXL20,were 19.3 times more resistant to paclitaxel and 67.4 times more resistant to cisplatin than the parent cells,and also demonstrated cross-resistance to mitomycin,vinblastine,and 5-fluouracil(5-FU). ③ Compared with the A549 celllines,an unreasonably higher level of drug resistance and lower drug concentration was detected in A549/TXL20 cells after exposure to the drug in the culture medium.④ The mRNA expression level of DNA pol?,mdr1,GST-?,mrp1 andlrp genes in A549/TXL20 cells was significantly higher than that in A549 cell lines(P

Objective:To evaluate the clinical efficacy of the bridge pedicled transplantation of medial leg fascial flap combined with medial hemisoleus muscle flap for contralateral leg soft tissue defect.Methods:Between January of 2012 and January of 2018, 12 patients with soft tissue defect of the leg were treated with bridge pedicled transplantation of contralateral medial leg fascial flap combined with medial hemisoleus muscle flap by posterior tibial artery. There were 9 males and 3 female, aged from 19 to 53 years (mean, 35 years). The size of the soft-tissue defects ranged from 12 cm×8 cm to 18 cm×9 cm. The immediate coverage of the fascial and muscle flaps and vessel pedicle were repaired by a meshed split-thickness skin graft. The donor site was closed directly. After the transplantation of the one pedicle and two flaps survived, vascular pedicle was cut off.Results:All the fascial and muscle flaps survived completely. No clinical vascular deficiency was found on the fascial and muscle flaps postoperatively. One case developed distal muscle flap small skin graft necrosis, and spontaneous healed after 2 weeks of dressing change. Follow-up period ranged from 2.5 to 4.5 years (mean 3.8 years). A good contour was confirmed both at the recipient and donor sites. Satisfactory clinical results were obtained in this series.Conclusion:This method is suitable for the treatment of soft tissue defects of the leg with only one major blood vessel, which reduces the damage to the donor site.

Objective:To evaluate the efficacy of the repairing anterior tibial adjacent double wounds by transposition with single-pedicle two flaps of the medial head of gastrocnemius.Methods:Between January of 2012 and January of 2018, 10 patients with the anterior tibial adjacent double wounds (7 males and 3 female, aged from 21 to 45 years) were treated by transposition with single-pedicle two flaps of the medial head of gastrocnemius. The size of the soft-tissue defects ranged from 2.0 cm×2.5 cm to 4.5 cm×4.0 cm. The medial head of the gastrocnemius was divided into two flaps with a single pedicle to repair two adjacent wounds of the anterior tibial. The muscle flaps were immediately covered by a meshed split-thickness skin graft, and the wound in donor site was closed directly.Results:All the muscle flaps survived completely. No clinical vascular deficiency was found on the muscle flaps postoperatively. Small wound dehiscence was developed in one patient and spontaneously healed 2 weeks after dressing change. Patients were followed up for 2.0 to 4.5 years. A good contour was confirmed at the recipient and donor sites. Satisfactory clinical results were obtained in this series.Conclusion:This method is suitable for the repair of two adjacent small wounds of the anterior tibial which can reduce the damage to the donor site.

Cancer stem cells (CSCs), a subpopulation of cancer cells with ability of initiating tumorigenesis, exist in many kinds of tumors including breast cancer. Cancer stem cells contribute to treatment resistance and relapse. Conventional treatments only kill differentiated cancer cells, but spare CSCs. Combining conventional treatments with therapeutic drugs targeting to CSCs will eradicate cancer cells more efficiently. Studying the molecular mechanisms of CSCs regulation is essential for developing new therapeutic strategies. Growing evidences showed CSCs are regulated by non-coding RNA (ncRNA) including microRNAs and long non-coding RNAs (lncRNAs), and histone-modifiers, such as let-7, miR-93, miR-100, HOTAIR, Bmi-1 and EZH2. Herein we review the roles of microRNAs, lncRNAs and histone-modifiers especially Polycomb family proteins in regulating breast cancer stem cells (BCSCs).
Breast Neoplasms ; genetics ; metabolism ; pathology ; Histones ; metabolism ; Humans ; Neoplastic Stem Cells ; metabolism ; RNA, Untranslated ; genetics ; metabolism