In an effort to explore potential ties between cholesterol levels and head and neck squamous cell carcinoma (HNSCC) risk, researchers reporting in PLOS Genetics consider the consequences of germline genetic variants with known cholesterol associations. The team focused on low-density lipoprotein cholesterol-lowering variants in five genes for a genome-wide association study of oral or oropharyngeal cancer risk that included nearly 188,600 individuals. While lower-than-usual LDL cholesterol in general did not appear to significantly influence the HNSCCs considered in their GWAS or follow-up analyses, the authors saw an apparent association between cholesterol-lowering variants in the PCSK9 gene and increased oral or oropharyngeal cancer risk. In contrast, variants in the LDLR gene that correspond with lower LDL cholesterol levels corresponded to lower-than-usual oral or oropharyngeal cancer risk. From these and other results, they suggest that the PCSK9-related risk "may be independent of cholesterol-lowering."
Canadian researchers compare microbial community profiles in non-small cell lung cancer (NSCLC) with those from unaffected lung tissue from the same participants for a paper in PLOS One. Based on 16S ribosomal RNA gene sequencing on matched tumor and normal samples from 29 individuals being treated for pulmonary adenocarcinoma or squamous cell carcinoma with lobectomy surgery, the team found that NSCLC and adjacent normal samples from the same patients tended to be more comparable than samples from different patients, though the extent of that similarity varied between individuals. "Each patient seems to possess its own bacterial signature," the authors report, noting that "[t]he two types of cancer tissue do not have a distinct bacterial profile that is shared by ever patient." Even so, they report, "the findings hint that "enteric, potentially pathogenic and pro-inflammatory bacteria were more frequently found in cancer than healthy tissue."
In PLOS One, a team from the US and Taiwan considers high-risk human papillomavirus prevalence in oropharyngeal cancers in Taiwan. Using multiplex HPV PCR MassArray-based testing for HPV genetic material, coupled with p16 staining for the virus, the researchers searched for HPV in formalin-fixed, paraffin-embedded oropharyngeal squamous cell carcinoma (OPSCC) in tumor samples from 541 individuals treated at a hospital in Taoyuan over nearly two decades, between the late 1990s and 2016. Their results suggest that some 28 percent of the successfully tested tumors were HPV-positive, particularly in individuals diagnosed with OPSCC when they were older, with HPV16 turning up most frequently. The presence of HPV appeared to coincide with longer disease-free and overall survival times, the authors note, while alcohol use was linked to earlier recurrence and death. "We found that HPV is present and likely an increasing etiological factor in these Taiwanese individuals with OPSCC," they write.