Using formalin fixed paraffin embedded tissue to characterize the microbiota in p16-positive and p16-negative tongue squamous cell carcinoma: a pilot study

BACKGROUND

Tongue squamous cell carcinoma (TSCC) is the most common oral cavity cancer, and p16 immunohistochemistry is an exact and available tool in the prognostic and predictive characterization of squamous cell cancers in the head and neck. Microorganisms have a close relationship with the development of TSCC. However, the association between oral bacteria and p16 status has not been well defined in the case of TSCC. Compared with traditional clinical microbial collection methods, formalin-fixed paraffin-embedded (FFPE) tissue samples have several advantages.

METHODS

To compare the microbiota compositions between p16-positive and p16-negative patients with TSCC, we performed a small pilot study of microbiological studies of TSCC by paraffin tissue. DNA from FFPE tissue blocks were extracted and microbiomes were profiled by sequencing the 16 S-rRNA-encoding gene (V1-V2/V3-V4/V4 regions). Alterations in the functional potential of the microbiome were predicted using PICRUSt, Tax4Fun, and BugBase.

RESULTS

A total of 60 patients with TSCC were enrolled in the study, however, some challenges associated with DNA damage in FFPE tissues existed, and only 27 (15 p16-positive and 12 p16-negative) passed DNA quality control. Nevertheless, we have tentatively found some meaningful results. The p16 status is associated with microbiota diversity, which is significantly increased in p16-positive patients compared with p16-negative patients. Desulfobacteria, Limnochordia, Phycisphaerae, Anaerolineae, Saccharimonadia and Kapabacteria had higher abundances among participants with p16-positive. Moreover, functional prediction revealed that the increase of these bacteria may enhance viral carcinogenesis in p16-positive TSCC.

CONCLUSIONS

Bacterial profiles showed a significant difference between p16-positive TSCC and p16-negative TSCC. These findings may provide insights into the relationship between p16 status and the microbial taxa in TSCC, and these bacteria may provide new clues for developing therapeutic targets for TSCC.

Androgen receptor expression in male breast cancer predicts inferior outcome and poor response to tamoxifen treatment

OBJECTIVE

Androgen receptor (AR) plays an important role in male breast cancer (MBC). Additionally, endocrine therapy is the most important treatment in oestrogen receptor (ER)-positive advanced breast cancer. This study was aimed to investigate the role of AR in MBC treatment and prognosis and to analyse the relationship between AR and the effect of tamoxifen treatment in MBC patients.

METHODS

AR protein levels and other tumour characteristics (e.g. expression of ER (ESR1), PR (PGR), AR, HER2 (ERBB2) and Ki-67 (MKI67)) in breast cancer tissue from 102 MBC patients were determined using immunohistochemical analysis. Additionally, the relationship between AR status and clinicopathological features was analysed using the χ(2)-test. Association with survival was initially analysed using the Kaplan-Meier method and the log-rank test, and Cox regression analysis was used to adjust for other prognostic indicators.

RESULTS

High expression of AR was not correlated with T-stage, histological grade, HER2 status and the status of other sex hormone receptors, but was associated with lymph node metastases (P=0.032). AR-positive patients showed significantly shorter 5-year overall survival (OS) rates (P=0.045) and 5-year disease-free survival (DFS) rates (P=0.026) than AR-negative patients. By contrast, for patients who received tamoxifen therapy, AR-negative patients showed a higher clinical benefit rate than AR-positive patients (P=0.025). Additionally, the median TTP and OS were significantly different (P=0.02 for TTP; P=0.029 for OS).

CONCLUSIONS

AR expression correlates strongly with both OS and DFS in patients with MBC. AR-positive patients can predict a poorer clinical outcome than AR-negative patients after adjuvant tamoxifen therapy.

Somatic mutation of KIT is rare in small cell lung cancer patients from Northeast China

Studies have confirmed that protein overexpression or mutations of KIT are involved in growth and development of a variety of cancers. however, little is known about data of gene mutation and protein expression in small cell lung cancer (SCLC) patients from northeast China.The aim of study is to investigate gene mutation and protein expression in such patients with small cell lung cancer (SCLC) and analyse their clinical significance.The expression of c-Kit protein was analyzed by immunohistochemistry in 77 SCLC samples and 22 normal lung samples. KIT mutations were screened in exons 9, 11, 13, 14, 17 and 18 by DNA direct sequencing.The study showed that positive staining for c-Kit was observed in 28 of 77 SCLC patients . There was no correlations between expression of c-Kit and sex, ages, smoking status, stage. only 1 case was found to have known T801I mutation in exon 17. The median survival (13.9 months) of cases with c-Kit-positive was shorter than that (19.9 months) of cases with c-Kit-negative. The finding revealed that stages was identified as an independent predictive factor for SCLC patients.Our finding reveals that somatic mutation of KIT is rare in SCLC patients from the northeast China and there is no enough evidence comfirming KIT inhibitors for treatment in SCLC.