HER2-amplified colorectal cancer

Subtype of Colorectal cancer

Clinical / Scientific

ERBB2 amplification is an uncommon CRC subset and a bypass of anti-EGFR therapy. Anti-HER2 strategies are molecularly rational; they are not the same evidence base as HER2+ breast cancer.

Core Biological Drivers

HER2 amplification

ERBB signalling bypass.

Key Pathways

HER2

Scientific explanation

HER2/ERBB2 amplification or overexpression produces ligand-independent ERBB signalling, classically in a subset of breast and gastroesophageal cancers and rarely in colorectal cancer.

MAPK/ERK

Scientific explanation

The RAS–RAF–MEK–ERK cascade transmits mitogenic RTK signals to programmes for proliferation and differentiation.

PI3K/AKT

Scientific explanation

phosphorylates PIP2 to PIP3, recruiting . supports growth, survival, glucose uptake and mTORC1 input. Pathway activation is common via PIK3CA mutation, PTEN loss or -tyrosine- signalling.

EGFR

Scientific explanation

EGFR is an ERBB-family tyrosine . Ligand activation or mutation (notably NSCLC exon 19/L858R) drives and signalling.

Pathway Convergence

Target → pathway → downstream effect → biological consequence. Shared intersections are mechanistic maps, not protocols.

Growth-factor signalling

Ligand or mutation-driven RTK input feeds PI3K/AKT and mTORC1, supporting anabolic growth. This is a map of signalling, not a treatment protocol.

Receptor tyrosine kinase
↓
PI3K/AKT
↓
mTOR
↓
Protein synthesis / growth

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.

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

Incomplete ERBB suppression and RAS co-mutation.

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.

EGCG

In VitroMechanistically Plausible

Target / Mechanism

Green-tea catechin with in-vitro effects on RTKs, epigenetic enzymes and redox. Clinical anticancer efficacy is not established.

Cancer relevance

Catechin effects on RTKs and redox in vitro. Clinical anticancer efficacy is not established.

RTK / redox dish models. Convergence: EGFR, PI3K/AKT.

Metformin

Clinical / Human EvidenceIn VivoIn VitroMechanistically Plausible

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.

Research Context

  1. HER2. Slamon DJ, et al. Human breast cancer: correlation of relapse and survival with amplification of the HER-2/neu oncogene. Science. 1987;235(4785):177-182. https://doi.org/10.1126/science.3798106
  2. CRC TCGA. The Cancer Genome Atlas Network. Comprehensive molecular characterization of human colon and rectal cancer. Nature. 2012;487(7407):330-337. https://doi.org/10.1038/nature11252

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.