The Correlation Between Mitochondrial DNA Haplogroups And Squamous Cell Carcinoma Of The Larynx In The Chinese Of Hunan Province

Objective: To study the Correlation between mitochondrial DNA haplogroups and laryngeal squamous cell cancer of the larynx in the Chinese of hunan Province and investigate the mitochondrial genetic susceptibility to laryngeal squamous cell cancer.Methods:Informed consent was obtained from each patient and the study was approved by relevant ethical review committee,154 Han individuals were sampled in Hunan, China:80 cases of laryngeal Squamous Cell Carcinoma,74 cases of normal controls.The whole-blood of all samples was collected with EDTA anticoagulant, then the mitochondrial DNA was extracted from the whole-blood samples. The mitochondrial DNA D-loop and the coding region of subunit ND3, ND4 L of mitochondrial respiratory chain complex enzymes were amplified by PCR,then the PCR products were sequenced.With the standard sequence comparison to identify mutations.With the revised Cambridge Reference Sequence(r CRS) comparison to identify mutations, then every sample was divided into haplogroup.Compare differences in the frequency of mitochondrial DNA haplogroup distribution in the different groups.The analysis of the data was done by using SPSS software version 20.0 and the P-value of less than 0.05 was considered to be significant.Results:1.There were significant differences in the distribution frequencies of the mitochondrial DNA haplogroup B and the sub haplogroup D4 of haplogroup D in the LSCC cases and controls, the haplogroup B(17.5% vs.6.8%P=0.04,OR=2.93,95%Cl=0.99-8.58),the haplogroup D4(10% vs.0%, P=0.02, OR=1.11,95%Cl=1.03-1.62);2. There were no significant differences that In the squamous cell cancer cases, the frequencies of haplogroup A、B、C、D、F、G、M are 4.7%、20.9%、0%、16.3%、9.3%、7%、27.9%,respectively,with the age at examination≥50years and with the age at examination<50years the frequencies of haplogroup A、B、C、D、F、G、M are 16.2%、13.5%、5.4%、27%、13.5%、0%、27%, respectively(P>0.05).3. There were no significant differences that In the normal control cases, the frequencies of haplogroup A、B、C、D、F、G、M are 9.7%、7.3%、4.9%、26.8%、26.8%、2.5%、29.3%,respectively,with the age at examination≥50years and with the age at examination<50years the frequencies of haplogroup A、B、C、D、F、G、M are 6.1%、0%、0%、9.1%、9.1%、6.1%、21.2%, respectively(P>0.05).4. In the squamous cell cancer cases, there were no significant differences in the distribution frequencies of the mitochondrial DNA haplogroup B and haplogroup D4 with the squamous cell cancer clinical staging.Conclusion:1. The hapogroup B and D4 are mayincrease risk of squamous cell cancer in Hunan population,They can consider as squamous cell cancer genetic screening the reference marks;2. Distribution of mt DNA haplogroups frequencieswere not associated with age in Hunan population.