[Familial Y chromosome microdeletion with pericentric inversion of chromosome 19].

OBJECTIVE: To investigate the familial cytomolecular genetics of an infertile male. METHODS: We analyzed the clinical phenotypes and karyotypes of three males from the family of an infertile man, detected the sequence-tagged sites (STS) in the AZF deletions of the Y chromosome by multiplex polymerase chain reaction (PCR), and identified the target genes by multiplex ligation-dependent probe amplification (MLPA). RESULTS: The karyotypes of the proband and his brother were 46, XY, inv (19) (p13.3q13.1) and that of his father was 46, XY. The three males were all carriers of AZFc deletion of the Y chromosome, and all found with the same reduction of the gene copy number in the AZFb and AZFc regions. CONCLUSIONS: Combined use of karyotype analysis, Y chromosome STS PCR, and MLPA revealed the genetic causes of the male infertile family.

Combination of gefitinib and DNA methylation inhibitor decitabine exerts synergistic anti-cancer activity in colon cancer cells.

Despite recent advances in the treatment of human colon cancer, the chemotherapy efficacy against colon cancer is still unsatisfactory. In the present study, effects of concomitant inhibition of the epidermal growth factor receptor (EGFR) and DNA methyltransferase were examined in human colon cancer cells. We demonstrated that decitabine (a DNA methyltransferase inhibitor) synergized with gefitinib (an EGFR inhibitor) to reduce cell viability and colony formation in SW1116 and LOVO cells. However, the combination of the two compounds displayed minimal toxicity to NCM460 cells, a normal human colon mucosal epithelial cell line. The combination was also more effective at inhibiting the AKT/mTOR/S6 kinase pathway. In addition, the combination of decitabine with gefitinib markedly inhibited colon cancer cell migration. Furthermore, gefitinib synergistically enhanced decitabine-induced cytotoxicity was primarily due to apoptosis as shown by Annexin V labeling that was attenuated by z-VAD-fmk, a pan caspase inhibitor. Concomitantly, cell apoptosis resulting from the co-treatment of gefitinib and decitabine was accompanied by induction of BAX, cleaved caspase 3 and cleaved PARP, along with reduction of Bcl-2 compared to treatment with either drug alone. Interestingly, combined treatment with these two drugs increased the expression of XIAP-associated factor 1 (XAF1) which play an important role in cell apoptosis. Moreover, small interfering RNA (siRNA) depletion of XAF1 significantly attenuated colon cancer cells apoptosis induced by the combination of the two drugs. Our findings suggested that gefitinib in combination with decitabine exerted enhanced cell apoptosis in colon cancer cells were involved in mitochondrial-mediated pathway and induction of XAF1 expression. In conclusion, based on the observations from our study, we suggested that the combined administration of these two drugs might be considered as a novel therapeutic regimen for treating colon cancer.

Effect of hyperoxia on the viability and proliferation of the primary type II alveolar epithelial cells.

To observe the effect of hyperoxia on the growth of type II alveolar epithelial cells (AEC II). The lungs of 19-day gestation fetal rats were primary cultured and the AEC II were purified by differential adhesion method. The cells were divided into control (normoxia) group and hyperoxia group. The cell growth, cell viability, cell apoptosis, and cell cycle were examined at 2, 4, 6, and 8 days of normoxia or hyperoxia exposure. The number of cells in hyperoxia-exposed group significantly decreased as compared to those of air control group. Number of cells in hyperoxia group was the highest at day 2 of exposure and gradually decreased with time. The viability of cells exposed to hyperoxia was substantially reduced compared with cells exposed to air. Percentage of cells in G1 phase and S phase in hyperoxia group increased gradually with increase in exposure duration and significant differences were seen at day 4 and day 6 compared with either the preceding time points and also with corresponding air-exposed cells. The percentage of both early apoptotic cells (Annexin-V(+)/PI(-)) and late apoptotic cells and necrotic cells (Annexin-V(+)/PI(+)) increased significantly in cells exposed to hyperoxia compared with cells exposed to air. Hyperoxia inhibits proliferation, viability and growth of AEC II and promotes apoptosis.

[Expression of MnSOD mRNA and protein in esophageal squamous cell carcinoma and its clinical significance].

OBJECTIVE: To investigate the expression of manganese superoxide dismutase (MnSOD) and to determine the relationship between MnSOD expression and clinicopathological features, biological behaviors in esophageal carcinoma. METHODS: Immunohistochemistry (SP) and RT-PCR were respectively used to detect the expression of MnSOD in 45 specimens of esophageal carcinoma tissues and normal esophageal mucosa (5 cm distant from the margin of cancer). RESULTS: The positive rate of MnSOD protein expression was 31.1% in esophageal carcinoma tissues, significantly lower than 86.7% in the normal tissues (P < 0.05). The expressions of MnSOD mRNA and protein were significantly correlated with the lesion length, depths of invasion and histological grade (P < 0.05), but not with lymph node metastasis, lesion site and gross type of the tumor (P > 0.05). The relative content of MnSOD mRNA was (0.310 ± 0.036) and (0.482 ± 0.053) in the cancer and normal tissues, respectively, with a significant difference between the two groups (P < 0.05). The relative content of MnSOD mRNA was significantly related to lesion length, depths of invasion and histological grade (P < 0.05), but not correlated with lymph node status, lesion site and gross type of the tumor (P > 0.05). CONCLUSION: The expression of MnSOD protein and mRNA is decreased in esophageal carcinoma, suggesting that MnSOD gene may be closely associated with the carcinogenesis and the degree of malignancy. Detection of MnSOD expression may be useful in diagnosis, treatment and prognosis of esophageal carcinoma.