Cancer / Oncology/Small-cell lung cancer
Thoracic · type
Small-cell lung cancer
Subtype of Lung cancer
Clinical / Scientific
SCLC is a high-grade neuroendocrine carcinoma with near-universal TP53 and RB1 inactivation, high mitotic rate, , and initially chemosensitive but rapidly resistant biology. DLL3/Notch and MYC family subtypes are research classifiers. Checkpoint blockade is established in some first-line combinations; most adjunctive metabolic ideas remain preclinical.
Core Biological Drivers
TP53 + RB1 loss
Defining genetic events.
MYC family
Subtype-defining amplification in a subset.
Notch / DLL3
Lineage and target biology.
Paracrine neuroendocrine secretion
Peptide and lineage programmes.
Key Pathways
Scientific explanation
TP53 encodes a stress-responsive factor controlling cell-cycle arrest, and metabolic adaptation. Loss or mutation is among the most common cancer events.
Scientific explanation
MYC factors coordinate biomass accumulation, ribosome biogenesis, and glutamine use. Amplification or pathway activation is common.
Scientific explanation
Notch receptors undergo ligand-induced cleavage to NICD, altering lineage and stem/progenitor decisions. Context determines oncogenic versus tumour-suppressive roles.
Scientific explanation
Aerobic (Warburg metabolism) supports ATP, biomass and redox buffering even when oxygen is available. Hexokinase, PKM2 and lactate export are frequent nodes.
Scientific explanation
Homologous-recombination defects (BRCA1/2 and related) create dependence on PARP-mediated repair. Mismatch-repair deficiency creates hypermutation and immune visibility.
Scientific explanation
Intrinsic and extrinsic apoptotic programmes remove damaged cells. Evasion of is a hallmark, via BCL-2 family imbalance, death- decoys, or p53 loss.
Scientific explanation
BCL-2, BCL-XL, MCL-1 and BAX/BAK control outer-membrane permeabilization, a core checkpoint frequently skewed toward survival in lymphoid and solid tumours.
Scientific explanation
PD-1 on T cells engaging PD-L1/PD-L2 restrains cytotoxic function. Tumour or myeloid PD-L1 is a canonical adaptive immune-evasion axis.
Scientific explanation
recycles organelles and can support survival under nutrient or therapy stress. Context determines tumour-suppressive versus therapy-protective roles.
Pathway Convergence
Target → pathway → downstream effect → biological consequence. Shared intersections are mechanistic maps, not protocols.
Energy stress
Energetic stress activates AMPK, which can restrain mTORC1. Biguanides and related tools map onto this axis in models.
Inflammatory survival
Chronic cytokine tone activates NF-κB and STAT3 transcriptional programmes that favour survival, invasion and sometimes immune evasion.
Mitochondrial stress
Electron-transport stress raises ROS; NRF2-driven transcription can buffer that stress and support survival. Antioxidant interventions are dual-edged.
Metabolic Vulnerabilities
Aerobic supports ATP, biomass and acidification even when oxygen is available. Extent varies by tumour and remains a vulnerability hypothesis rather than a uniform target.
Glutamine anaplerosis and nucleotide nitrogen demand are prominent in MYC-high and rapidly proliferating tumours. Dependence is heterogeneous.
Tumor Microenvironment
Disordered vasculature creates , HIF-1α stabilization, induction and immune-suppressive adenosine/lactate milieus.
Metastasis Module
, protease-mediated invasion, , circulating tumour-cell survival and organ-specific colonization form the metastatic cascade. Pre-metastatic niches and vascular permeability influence tropism.
Resistance Biology
Rapid chemoresistance involves apoptotic threshold change, DNA-repair adaptation and lineage subtype switching.
Cancer Stemness
Wnt, Notch, Hedgehog, ALDH and CD44-associated programmes can mark stem-like fractions with quiescence and therapy tolerance. These markers are not interchangeable across tumour types.
Mechanism-Based Adjunctive Strategies
Compounds appear only where a mechanistic overlap exists for this cancer. Evidence tiers are not equivalent. Nothing here is a treatment recommendation.
Target / Mechanism
Benzimidazole that binds β-. Mammalian disruption, mitotic arrest and related signalling in cancer models are preclinical and are not an approved anticancer use.
Cancer relevance
disruption can trigger mitotic stress and in cell and animal models. This is not an established oncology use.
Experimental antimitotic / microtubule stress. Convergence: Apoptosis, p53.
Target / Mechanism
Lysosomotropic agent that raises endosomal/autophagosomal pH, impairing flux. Combination trials in oncology have been mixed; blockade is not equivalent to proven benefit.
Cancer relevance
Lysosomal pH elevation impairs flux. Early combination trials exist; benefit is not established and toxicity/retinal risk remain labelled concerns.
Autophagy-modulation research combinations. Convergence: Autophagy.
Disulfiram
Target / Mechanism
ALDH ; copper-complexed forms can inhibit proteasome and NF-κB-related survival programmes in models. Clinical oncology evidence remains limited.
Cancer relevance
ALDH and copper-dependent proteasome/NF-κB stress in models; clinical oncology remains limited.
ALDH / redox experimental context. Convergence: Cancer stemness, NF-κB, Oxidative stress.
Target / Mechanism
Modest complex I inhibition raises AMP:ATP, activating and restraining hepatic and -linked anabolism. Direct antineoplastic efficacy is not established from that pharmacology alone.
Cancer relevance
activation and restraint provide a metabolic rationale in - and -linked tumours. Human data are mixed and do not establish metformin as cancer therapy.
Metabolic adjunctive research context. Convergence: AMPK, mTOR, Glycolysis.
Target / Mechanism
uncoupler in cestodes; mammalian models report , Wnt/β-catenin and modulation. Those host-signalling findings are investigational/preclinical.
Cancer relevance
Models report Wnt/β-catenin, and effects. Host signalling findings remain investigational.
Wnt / STAT3 signalling models. Convergence: Wnt/β-catenin, JAK/STAT, mTOR.
Research Context
- Hallmarks. Hanahan D, Weinberg RA. Hallmarks of cancer: the next generation. Cell. 2011;144(5):646-674. https://doi.org/10.1016/j.cell.2011.02.013
- Warburg. Vander Heiden MG, Cantley LC, Thompson CB. Understanding the Warburg effect: the metabolic requirements of cell proliferation. Science. 2009;324(5930):1029-1033. https://doi.org/10.1126/science.1160809
- Resistance. Holohan C, Van Schaeybroeck S, Longley DB, Johnston PG. Cancer drug resistance: an evolving paradigm. Nat Rev Cancer. 2013;13(10):714-726. https://doi.org/10.1038/nrc3599
This oncology atlas is educational. Pathway maps, adjunctive strategies, and compound listings describe mechanistic relevance. They do not establish clinical efficacy, do not recommend treatment, and are not a substitute for oncology care. Evidence tiers are not equivalent.