Establishing the keratinocyte stem cell basis for skin field cancerisation and squamous cell carcinoma

Grantee: Girish Patel, Honorary Senior Lecturer, Cardiff University, UK

Amount: DKK 3,935,737

Epithelial tissues, the environmental barriers of our bodies, are constantly exposed to cancer causing agents. As such carcinoma, the cancer of epithelial tissues, are the most common form of cancer accounting for 85% of all cancers and 78% of all cancer associated deaths.

Many carcinomas arise from a pre-cancerous transformation, known as intraepithelial neoplasia or field cancerisation (FC), within which multiple carcinoma can develop.

By studying skin FC in a mouse model of human papillomavirus 8 infection (K14-HPV8-CER), we have uncovered specific expansion of only the Lrig1 hair follicle junctional zone keratinocyte stem cells (HFJZKSC) driven by ΔNp63 expression, which is the basis for skin FC 1-3.

These findings raised two important fundamental questions:

  1. How does HPV8 induce Lrig1 KSC expansion? The background for this proposal and ongoing work (Leo Foundation grant 2017, LF17070).
  2. Are Lrig1 derived cells responsible for squamous cell carcinoma (SCC)? The basis for this Leo grant proposal.

The current Leo Foundation grant allowed us to identify E6 as the HPV8 protein responsible for Lrig1 KSC expansion through activation of the STAT3 intracellular signalling pathway.

Therefore, we are now positioned for a follow-on grant to determine whether Lrig1 derived cells are responsible for FC associated SCC. Herein we aim to:

1) confirm that Lrig1 HFJZKSC proliferation is responsible KSC expansion into the infundibulum and adjoining interfollicular epidermis

2) test the hypothesis that Lrig1 HFJZKSC progeny give rise to papilloma and SCC

3) determine whether STAT3 mediate HFJZKSC expansion occurs in human skin FC.