Objective To evaluate the effect of intrathecal methotrexate on activation of spinal astrocytes in a rat model of bone cancer pain (BCP).Methods Sixty female unmated Sprague-Dawley rats,aged 5-7 weeks,weighing 150-180 g,were randomly divided into 3 groups (n =20 each) using a random number table:sham operation group (group S),BCP group (group P),and BCP + methotrexate group (group PM).BCP was induced by injecting Walker-256 cancer cells into the medullary cavity of tibia.On day 7 after BCP,methotrexate 100 μg (diluted to 15 μl in artificial cerebrospinal fluid) was injected intrathecally over 10 s in group PM,and artificial ccrebrospinal fluid 15 μ1 was injected intrathecally over 10 s in S and P groups.The mechanical paw withdrawal threshold (MWT) was measured at 1 day before BCP and 3,7,14 and 21 days after BCP.Five rats were sacrificed after measurement of the pain threshold at 7,14 and 21 days after BCP,and the lumbar enlargement segments of the spinal cord were harvested for detection of the expression of glial fibrillary acidic protein (GFAP) by immuno-histochemistry.Five rats were sacrificed after measurement of the pain threshold at 14 days after BCP,and the expression of GFAP in the spinal cord was detected by Western blot.Results Compared with group S,the MWT was significantly decreased at 3,7,14 and 21 days after BCP in C and CM groups,the expression of GFAP was significantly up-regulated at each time point after BCP in group C,and the expression of GFAP was significantly up-regulated at 7 and 14 days after BCP in group CM (P＜0.05).Compared with group C,the MWT was significantly increased,and the expression of GFAP was significantly down-regulated at 14 and 21 days after BCP in group CM (P＜0.05).Conclusion The mechanism by which intrathecal methotrexate reduces BCP may be related to inhibition of spinal astrocyte activation in the rats.

Objective:To detect the status of PIK3CA in triple-negative breast cancer (TNBC) , and to analyze the relationships between PIK3CA mutation and clinical features and its impact on prognosis.Methods:From January 1, 2016 to December 31, 2018, 50 patients with primary TNBC admitted to Xinxiang Central Hospital of Henan Province were collected. The PIK3CA mutation status was detected, and the relationships between PIK3CA mutation and clinical characteristics of patients with TNBC and its impact on prognosis were analyzed.Results:PIK3CA gene mutation was detected in 9 of 50 TNBC patients, with a mutation frequency of 18.0%. H1047R mutation was found in 4 cases, E545K mutation in 3 cases and E542K mutation in 2 cases. PIK3CA gene mutation was not associated with age ( χ2=3.55, P=0.060) , tumor location ( χ2=1.01, P=0.315) , tumor size ( χ2<0.01, P>0.999) , lymph node status ( χ2=0.76, P=0.385) , clinical stage ( χ2=0.65, P=0.420) , Ki-67 value ( χ2<0.01, P>0.999) , P53 status ( χ2=0.02, P=0.894) and human epidermal growth factor receptor-2 (HER-2) status ( χ2=1.65, P=0.200) . Prognostic analysis showed that 3-year disease-free survival rates of wild-type PIK3CA patients was significantly higher than that of mutant PIK3CA patients (80.5% vs. 11.1%, χ2=28.23, P<0.001) . Conclusion:The frequency of PIK3CA gene mutation is higher in TNBC patients. There is no correlation between PIK3CA mutation and clinicopathologic features in TNBC patients. PIK3CA gene mutation may be significantly associated with poor prognosis of TNBC patients.