Objectives:
This study aimed to quantify Haemophilus parainfluenzae (H. parainfluenzae) by percent average relative abundance, in oral squamous cell carcinoma (OSCC) tissues among a cohort of male patients. Comparisons were also made on the occurrence of H. parainfluenzae by selected host factors such as socio-demographic characteristics, life-style-related risk habits, site of the lesion and periodontal disease indicators.
Materials and Methods:
The sample comprised a 25 histologically confirmed OSCC tissues of male patients attended selected Oral & Maxillofacial (OMF) Units of public hospitals across Sri Lanka. This was a representative subset of a main unmatched case control study. The V1 to V3 region of the 16S r- RNA gene was amplified for sequencing using the degenerate primers. Sequencing, data processing and taxonomy assignment up to species level were accomplished by using standard methodologies. Comparisons were made on occurrence of H. parainfluenzae by age group, educational attainment, frequency of betel quid chewing, smoking, alcohol consumption, site of the lesion, oral hygiene status and periodontal disease status using Fisher’s exact test.
Results:
The percent average relative abundance of H. parainfluenzae of OSCC tissues was 2.99 % and the occurrence of H. parainfluenzae in 80% of samples were less than 2.99%. There were no statistically significant differences in the occurrence of H. parainfluenzae by socio-demographic factors, frequency of life-style risk habits, site of the OSCC and periodontal disease indicators.
Conclusions:
Our preliminary findings demonstrated occurrence of H. parainfluenzae, a significant bacterial species increasingly linked with dysbiosis of oral cancers in the OSCC tumour microenvironment of male patients. Within the limitations of the present study, further research is warranted to generate more conclusive evidence on quantification of H. parainfluenzae in OSCC tissues and to determine related host factors in comparison with matched healthy controls powered by larger sample sizes.