结核分枝杆菌L-型感染与肺癌的相关性初步研究

Study on the relationship between Mycobacterium tuberculosis L infection and lung cancer

目的:探寻结核分枝杆菌L-型(Mycobacterium tuberculosis L-forms,MTB-L)感染与肺癌发生的相关性。方法:实验设肺癌组(167例)、结核病组(65例)及非结核、非恶性肿瘤对照组(60例)。对各组的手术切除组织标本,分别用IK(intensified Kinyoun’s)抗酸染色检测MTB-L、经典抗酸(Ziehl-Neelsen,ZN)染色检测结核分枝杆菌(Mycobacterium tuberculosis,MTB)、原位杂交(in situ hybridization,ISH)检测MPB64基因在癌细胞核内的表达,并对部分标本进行细菌培养。结果:肺癌组患者中MTB-L阳性率为67.1%(112/167),MTB-杆菌型的阳性率为4.2%(7/167),2者比较差异有统计学意义(P<0.05)。肺癌组与结核病组(90.8%,59/65)的MTB-L比较,差异有统计学意义(P<0.05),与非结核、非恶性肿瘤对照组的1.7%(1/60)比较,差异有统计学意义(P<0.05)。肺癌组MPB64基因(癌细胞核内表达)的阳性率为80.2%(134/167),与结核病组的100%(65/65)比较,差异有统计学意义(P<0.05),与非结核、非恶性肿瘤对照组的3.3%(2/60)比较,差异有统计学意义(P<0.05)。肺癌组中各组织类型、组织学分级、病理分期及淋巴结有、无转移的MTB-L检测结果之间,差异均无统计学意义(P均>0.05),MPB64基因检测结果之间,差异均无统计学意义(P均>0.05)。有、无结核病史者MTB-L检测结果之间、MPB64基因检测结果之间,差异均无统计学意义(P均>0.05)。肺癌组47例标本培养检出人型MTB-L27株(57.4%),返祖为原杆菌型者的有18株(66.7%,18/27)。MTB-L与MTB(4.3%,2/47)检出率比较,差异有统计学意义(P<0.05)。结论:肺癌组织中MTB主要以L型存在;MTB-L的MPB64基因在肺癌组织的癌细胞核内高度表达;MTB-L与MPB64基因检测阳性率与各病理学特征及结核病史无关。

Objective：To explore the relationship between Mycobacterium tuberculosis L（MTB-L） infection and tumorigenesis of lung cancer. Methods：One hundred and sixty seven patients with lung cancer, 65 patients with tuberculosis, 60 non-cancer and non- tuberculosis patients as control group were included in the study. MTB-L in surgically resected specimens were detected by Intensified Kinyoun＇ s（IK） staining and MTB was detected by Ziehl-Neelsen staining. In situ hybridization （ISH）technique was used to determine the MPB64 gene＇ s expressions in nucleus of lung cancer cells. MTB and MTB-L in some specimens were cultured. SPSS 13.0 software was used for statistical analysis. The positive rates between groups were compared with chi-square test. Results：The positive rate of MTB-L in lung cancer patients was 67.1% （ 112/167 ） and the positive rate of MTB was 4.2% （7/167）, and the difference was signifi- cant between the two groups（ P 〈 0.05 ）. The positive rate of MTB-L in tuberculosis group （90.8%, 59/65 ）was significantly different compared with lung cancer group（ P 〈 0.05 ） and control group （ 1.7%, 1/60 ） （ P 〈 0.05 ）. There was significant difference in MPB64 gene expression in cell nucleus between lung cancer group and tuberculosis group [ 80.2% （134/167）vs 100% （65/65）, P 〈 0.05 ] and between lung cancer group and control group [ 80.2% （134/167）vs 3.3% （2/60）, P 〈 0.051- MTB-L level and MPB64 gene expres- sion had no significant difference between lung cancer tissues with various histological classifications, pathological grade, clinical sta- ging, and lymph node metastasis （ all P 〉 0.05 for MTB-L and all P 〉 0.05 for MPB64）. There was no significant difference in MTB- L level and MPB64 gene expression between the patients with and without tuberculosis history （ all P 〉 0.05 ）. Twenty seven strains of human type MTB-L （57.4%）and 18 （66.7%）strains come back to the ancestors MTB were detected out of 47 lung cancer specimens, and the difference was significant （ P 〈 0.05 ）. Conclusion： MTB-L is the primary type of MTB existing in the lung cancer tissues. MPB64 is highly expressed in the nucleus of lung cancer cells. MTB-L and MPB64 have no correlation with pathological features and tu- berculosis history.