Abstract
Background: Oral cavity cancer is a subgroup of head and neck cancer which is the world’s 6th most common cancer form. Oral squamous cell carcinomas (OSCC) constitute almost all oral cavity cancers, and OSCC are primarily attributed by excessive alcohol consumption and tobacco exposure. There is a lack of good tools to provide more accurate prognosis; biomarkers could be such a tool.
Methods: Five patients with stage IV OSCC with cervical lymph node involvement
were included and 6 samples were collected: One blood sample, 1 sample from
clinically healthy tissue, 3 tumour biopsies and 1 lymph node biopsy. Whole exome sequencing was carried out on the Illumina HiSeq1500 platform with paired-end 2x100 base-pair reads. Additional data analysis was performed for copy number variation.
Results: Mean sequence coverage was 93.6x with 84 % of bases covered by at least 20 read. An average of 479.1 somatic mutations were identified; 44.7 mutations per sample were identified as coding variants or splice site mutations. In our population, 13 genes have been identified with a mutation occurring in 2 or more patients. Mutations in TP53 were identified in 4 patients, MUC16 was seen mutated in 3 patients and the remaining gene mutations were identified in 2 patients. Two identical somatic mutations were observed in two different patients. The analysis of intra tumour heterogeneity and lymph node involvement shows that specimens in each patient are very homogenous, but evidence of heterogeneous subpopulations of tumour cells exists.
Conclusions: Use of next generation sequencing in oral cavity cancer can give
valuable insight into the biology of the disease. By investigating intra tumour
heterogeneity we see that the different tumour specimens in each patient are quite homogenous, but evidence of heterogeneous subpopulations exists with unique alterations that could give them a selective advantage in tumour growth and perhaps in drug resistance. Overall, analysis of lymph node involvement has shown that the samples are quite homogenous with the primary tumour, but also that different subpopulations with selective advantages could exist.
Methods: Five patients with stage IV OSCC with cervical lymph node involvement
were included and 6 samples were collected: One blood sample, 1 sample from
clinically healthy tissue, 3 tumour biopsies and 1 lymph node biopsy. Whole exome sequencing was carried out on the Illumina HiSeq1500 platform with paired-end 2x100 base-pair reads. Additional data analysis was performed for copy number variation.
Results: Mean sequence coverage was 93.6x with 84 % of bases covered by at least 20 read. An average of 479.1 somatic mutations were identified; 44.7 mutations per sample were identified as coding variants or splice site mutations. In our population, 13 genes have been identified with a mutation occurring in 2 or more patients. Mutations in TP53 were identified in 4 patients, MUC16 was seen mutated in 3 patients and the remaining gene mutations were identified in 2 patients. Two identical somatic mutations were observed in two different patients. The analysis of intra tumour heterogeneity and lymph node involvement shows that specimens in each patient are very homogenous, but evidence of heterogeneous subpopulations of tumour cells exists.
Conclusions: Use of next generation sequencing in oral cavity cancer can give
valuable insight into the biology of the disease. By investigating intra tumour
heterogeneity we see that the different tumour specimens in each patient are quite homogenous, but evidence of heterogeneous subpopulations exists with unique alterations that could give them a selective advantage in tumour growth and perhaps in drug resistance. Overall, analysis of lymph node involvement has shown that the samples are quite homogenous with the primary tumour, but also that different subpopulations with selective advantages could exist.
| Originalsprog | Engelsk |
|---|---|
| Publikationsdato | 2015 |
| Status | Udgivet - 2015 |
| Begivenhed | DSPR Forårsmøde 2015 - Panum, København, Danmark Varighed: 8. maj 2015 → 8. okt. 2015 |
Konference
| Konference | DSPR Forårsmøde 2015 |
|---|---|
| Lokation | Panum |
| Land/Område | Danmark |
| By | København |
| Periode | 08/05/2015 → 08/10/2015 |