Reprogramming the Tumor Microenvironment: Calebin A as a Polyphenolic Paradigm Shift in Controlling Inflammation, Stemness, and Resistance in Colorectal Cancer

Colorectal cancer (CRC) remains a leading cause of cancer mortality worldwide, largely due to inflammation-driven progression, cancer stemness, and multidrug resistance (MDR). The tumor microenvironment (TME) orchestrates these hallmarks through persistent NF-κB activation and cross-talk among stromal, immune, and cancer cells. This review consolidates mechanistic evidence on Calebin A (CA), a non-curcuminoid polyphenol from Curcuma longa, as a novel multitargeted agent capable of reprogramming the TME and redefining anticancer therapy. A literature integration was conducted across in vitro, ex vivo, and 3D TME models to assess CA's molecular targets, signaling pathways, and pharmacological challenges. CA directly interacts with redox-sensitive cysteine residues in NF-κB (p65) and IKKβ, inhibiting their activation and downstream transcriptional programs. This leads to decreased expression of MMP-9, CXCR4, β1-integrin, and CSC markers (CD44, CD133, ALDH1), along with activation of caspase-3-mediated apoptosis. Moreover, CA reverses MDR by suppressing cytokine-mediated stromal signaling, normalizing redox balance, and enhancing chemosensitivity to 5-FU and cisplatin. Emerging data from other malignancies reveal CA's ability to modulate STAT3, Wnt/β-catenin, and PI3K/Akt pathways, highlighting its universal microenvironmental reprogramming potential. Calebin A represents a polyphenolic paradigm shift in oncology-an agent that restores systemic homeostasis within the TME rather than merely inhibiting oncogenic pathways. Overcoming bioavailability challenges through nanotechnology and combination therapy may accelerate its clinical translation, positioning CA as a prototype for next-generation ecological therapeutics in cancer management. This review consolidates mechanistic evidence on Calebin A (CA), a non-curcuminoid polyphenol from Curcuma longa, as a novel multitargeted agent capable of reprogramming the TME and redefining anticancer therapy. A literature integration was conducted across in vitro, ex vivo, and 3D TME models to assess CA's molecular targets, signaling pathways, and pharmacological challenges. CA directly interacts with redox-sensitive cysteine residues in NF-κB (p65) and IKKβ, inhibiting their activation and downstream transcriptional programs. This leads to decreased expression of MMP-9, CXCR4, β1-integrin, and CSC markers (CD44, CD133, ALDH1), along with activation of caspase-3-mediated apoptosis. Moreover, CA reverses MDR by suppressing cytokine-mediated stromal signaling, normalizing redox balance, and enhancing chemosensitivity to 5-FU and cisplatin. Emerging data from other malignancies reveal CA's ability to modulate STAT3, Wnt/β-catenin, and PI3K/Akt pathways, highlighting its universal microenvironmental reprogramming potential. Calebin A represents a polyphenolic paradigm shift in oncology-an agent that restores systemic homeostasis within the TME rather than merely inhibiting oncogenic pathways. Overcoming bioavailability challenges through nanotechnology and combination therapy may accelerate its clinical translation, positioning CA as a prototype for next-generation ecological therapeutics in cancer management.