Correlative Study On Changes Of Intestinal Flora Before And After Ep Regimen Chemotherapy In Small Cell Lung Cancer

Research Background:At present,lung cancer are the most common one of the malignant tumors in the world,its morbidity and mortality are the highest in malignant tumors.Histologically,lung cancer can be divided into non-small cell lung cancer(NSCLC)and small cell lung cancer(SCLC),NSCLC 85%,SCLC about 15%.SCLC is a class of neuroendocrine tumors with early metastasis,rapid growth,highly sensitive to radiotherapy and chemotherapy.According to the latest NCCN guidelines,The main treatment of SCLC is systemic intravenous chemotherapy,EP(etoposide + cisplatin)as its standard first-line treatment program.Chemotherapy drugs can cause all kinds of adverse reactions,nausea,vomiting,abdominal pain,diarrhea,abdominal distension and other gastrointestinal reactions is one of the most common side effects,these adverse reactions not only reduce the quality of life of patients,but also affect the efficacy of chemotherapy.Studies have shown that chemotherapy-induced gastrointestinal symptoms are closely related to intestinal flora [1].However,in recent years,the correlation between intestinal flora and lung cancer rarely reported,and small cell lung cancer chemotherapy research is no report.Now through the qualitative analysis of small cell lung cancer EP regimen before and after treatment of intestinal microflora structure and composition,To understand the changes of intestinal flora before and after SCLC chemotherapy in EP regimen.So as to clarify the relationship between SCLC chemotherapy and intestinal microflora changes,reduce the incidence of adverse reactions,improve the quality of life of patients,improve the efficacy of chemotherapy and prolong the survival of patients.Method:1?Clinical sample collection: 14 patients were enrolled in the study,They all pathologically were diagnosed with small cell lung cancer In the second hospital affiliated to Dalian Medical university.and They all adopt EP chemotherapy,Respectively collected fresh feces before and after chemotherapy,And then stored in a-80 ? refrigerator,1-14 samples for group A,B group of 15 to 28 samples.2?Fecal DNA extraction: Use E.Z.N.A.? Stool DNA Kit(200)extracted fecal DNA.3?Polymerase chain reaction-denaturing gradient gel electrophoresis(PCR-DG GE): The changes of intestinal microflora were studied by polymerase chain reactiondenaturing gradient gel electrophoresis(PCR-DGGE),To further complete the map analysis.4?Sequencing: The bands with significant were sequenced to identify the genus.5?Statistical analysis.Result:1?Sample collection: 14 patients were all successfully collected the fresh fecal samples before and after chemotherapy.2 ? Extraction of fecal DNA: The DNA were successfully extracted from the experimental samples,and the DNA concentration of each sample reached the experimental requirement.3?Characteristics of intestinal flora before and after EP regimen chemother apy in SCLC patients: The diversity index of intestinal flora in 14 patients aft er chemotherapy was slightly lower than that before chemotherapy,But the diff erence was not significant(P> 0.05).There was no significant difference in ab undance before and after chemotherapy(P> 0.05).4?Results of sequencing: Cutting the strips with obvious changes in DGG E spectra,It was found that the brightness of band 2,5,6 and 7was lower th an that before chemotherapy,and the brightness of bands 1,3 and 4 was stronger than that before chemotherapy.Band 1 is Parasutterella excrementihominis,homology is 95%,band 2 may be Lachnospiraceae bacterium,with 96% hom ology,the band 3 may be Clostridium sp,the homology is 86%,the band 4 is Subdoligranulum variabile,96% homology,The band 5 may be Peptoniphilu s sp,the homology is 83%,the band 6 is Pseudobutyrivibrio ruminis,its ho mology is 100%,the band 7 is Faecalibacterium prausni,and the homology i s 100%.5?The relationship between intestinal abundance(E),multivariate index(H)and related clinical factors in SCLC patients: The structure of intestinal flora i n SCLC patients was not significantly correlated with age,sex,clinical stage a nd adverse reactions such as gastrointestinal adverse reactions(P>0.05).Conclusion:1?The intestinal flora difference of SCLC patients EP program before and after chemotherapy was not significant.2?Changes of Intestinal Flora after EP Chemotherapy in SCLC Patients:The amount of Clostridium bacillus increased,the amount of Lachnospiraceae bacterium,Pseudobutyrivibrio ruminis decreased.3?There was no significant correlation between the intestinal flora of SCLC patients and the clinical factors such as age,sex,clinical stage and adverse reactions of gastrointestinal tract.