Cancer Stem Cells in Lung Cancer, a Novel Frontier

Lung cancerLung cancer is the major cause of cancer-related deaths worldwide, exhibiting one of the lowest 5-year survival rates, due, primarily, to its late-stage diagnosis. It is categorized into small cell lung cancer (SCLC) and non-SCLC (NSCLC), with NSCLC further subdivided into adenocarcinoma, squamous cell carcinoma, and large cell carcinoma. NSCLC is the most common lung cancer, accounting for 85% of all cases. Treatment approaches are diverse and based on cancer subtype and stage. Those include chemotherapy, radiation therapy, immunotherapy and surgery. Despite advancements in therapies, lung cancer patients often experience high recurrence rates, metastasis, and chemotherapy and immunotherapy resistance. Lung stem cells (SCs), possessing self-renewal and proliferation capabilities, are resistant to conventional treatments, potentially contributing to cancer development and progression. Their presence in the lung tissue could be one of the main reasons why lung cancer is difficult to aboard. The signaling pathways and specific biomarkers of lung stem cells are currently under investigation due to their relevance in the development of new therapeutic agents targeting these cell populations and aiming to enhance current therapies for lung cancerLung cancer treatment. In the following chapter, we update the knowledge on lung stem cells, focusing on signaling pathways and their specific biomarkers, and discuss their role in lung tumorigenesis.