Breast Cancer Prognostic Indicators And Clinical Treatment Research

(Part ?)BackgroundBranched-chain amino acid transferase 1(BCAT1)could increase tumor metabolism and proliferation by decomposing branched-chain amino acids.Tumor stem cell marker CD 133 could promote tumor cell proliferation and invasion.Studies suggested that BCAT1 and CD 133 showed prognostic correlation in liver and colorectal cancer.However,the correlation between the expression level of BCAT1 and CD133 and prognosis of breast cancer remains unclear.In this study,the correlation between BCAT1 and CD 133 expression and the survival of breast cancer patients,especially of the triple-negative breast cancer(TNBC)patients,were investigated.MethodsA collection of 40 patients with breast cancer were included with collected samples from tumor tissue and normal breast tissue.The transcriptional expression of BCATl and CD133 was determined by qRT-PCR on the genetic level and by Western blot on the protein expression level.In addition,21 patients with breast cancer were included with samples from tumor tissue and normal breast tissue.On the metabolic level,the relative quantity of BCAA was determined by liquid-phase separation column chromatography.Bioinformatics analysis showed that the expression of BCAT1 and CD133 in breast cancer had potential prognostic correlation with DFS of breast cancer patients.The epigenetic upstream regulatory mechanisms and downstream pathways related to BCAT1 in breast cancer were also analyzed by literature review.In addition,291 TNBC patients were included with samples from tumor tissue and normal breast tissue.Paraffin-embedded tissue microarrays were constructed,and immunohistochemical staining was used to semi-quantitatively determine the expression levels of BCAT1 and CD 133 by H-scoring system.The cut-off points of expression scores were determined by the receiver operating characteristic curve.The relationship between the expression and the clinico-pathological characteristics as well as the prognosis of TNBC was evaluated.Additionally,bioinformatics analysis in terms of metabolism and epigenetics was conducted to analyze the upstream regulatory mechanisms and downstream pathways of BCAT1 in TNBC.ResultsAmong the breast cancer patients,the gene expression levels of BCAT1 and CD 133 increased with the advanced tumor stage,histological grade and axillary lymph node metastasis.The protein expression signals of BCAT1 and CD 133 in TNBC were higher than those of other subtypes.On metabolic level,the quantity of free BCAA in breast cancer tissues was higher than that in normal breast tissues,and the relative quantity of BCAA was higher than that of non-branched chain amino acids.Bioinformatics analysis revealed that elevated expression le'vel of BCAT1 and CD 133 was associated with compromised disease-free survival(DFS)of breast cancer(p<0.01).Among the collection of 291 TNBC patients,the median follow-up time was 68.7 months(range 1.37-103.6 months).The 5-year DFS of all patients was 72.5%and the 5-year overall survival(OS)was 82.5%.On protein level,there were 36 cases(12.4%)of TNBC tumor tissues with high expression of both BCAT1 and CD133,and the DFS(p<0.01)and OS(p<0.01)of this subgroup were significantly compromised.Increased expression of BCAT1 and of CD 133 were both associated with a decrease in TNBC patients' DFS(p<0.01)and OS(p<0.01).In view of TNBC immune response,high level of tumor infiltrating lymphocytes(TIL)was associated with improved DFS(p=0.002)and OS(p=0.006).In addition,multivariate Cox regression showed that the independent prognostic factors associated with compromised DFS and OS of TNBC were:high BCAT1 expression(DFS p=0.003,OS p=0.001),high expression of CD133(DFS p<0.001,OS p=0.001)and low TIL(DFS p=0.007,OS p=0.033).ConclusionsThe gene expression of BCAT1 and CD 133 in breast cancer increased with tumor stage,axillary lymph node metastasis and histological grade.The metabolic level of BCAA in breast cancer tissue is increased,and the protein expression levels of BCAT1 and CD 133 were increased in TNBC.High levels of BCAT1 and CD 133 were associated with decreased DFS of breast cancer.In TNBC,high immune response TIL levels were associated with improved prognosis.The high expression of BCAT1 and CD 133 protein was correlated with unfavorable prognosis of TNBC as independent prognostic indicators of TNBC.(Part ?)BackgroundAromatase inhibitors(AI)during the endocrine therapy of breast cancer might increase the risk of bone loss and fractures.The exploration of Al-related fracture characteristics could lead to more efficient monitoring and intervention of AI-related adverse events of fractures and improve clinical treatment benefit.This part of the study explored the association and pathogenesis of AI with fractures by mining and analyzing the clinical and medication information of fracture adverse events in the FDA Adverse Drug Reaction System(FAERS)in the United States,aiming to provide specified guidance for individualized endocrine therapy.MethodsClinical and medication information of AI-related fracture events reported in the FAERS database were collected from January 1,2004 to December 31,2018.The association between AI medication regimens and fractures were analyzed with nonproportional and Bayesian statistical methods.The clinical characteristics such as time of onset and outcome of AI-related fractures in different medication regimens were analyzed by applying four statistical methods of correlation test,including report ratio,proportional report ratio,Bayesian confidence progressive neural network method and multivariate term gamma-poison segment reduction method.ResultsA total of 23064 AI-related adverse event reports were screened,of which 657(2.85%)were fracture-related.Association analysis by 4 statistical methods of showed all positive association signals with anastrozole and two positive association signals with letrozole and exemestane.Fracture outcome of "admission to hospital or extended hospitalization" was reported the most in exemestane reports(37.2%,p=0.012).There was no significant difference(p=0.236)in the duration of fracture onset under medication of anastrozole(25.93±25.05 months),letrozole(20.67±22.97 months)and exemestane(21.80±23.69 months).Among the secondary suspected drugs reported with all 3 AIs,CDK4/6 inhibitor was most frequently reported(34 cases,16.8%).ConclusionsNo significant difference was detected from the time under AI medication before the fractures.A more prominent association of anastrozole with fracture was suggested.Attention should be paid to the monitoring of bone-related adverse events during clinical use of AI in the endocrine therapy of breast cancer.