Across TCGA pan-cancer cohorts, IGKV4-1 mass-spec protein differs between tumor and matched normal tissue in 5 of 18 cancer types tested, making tumor–normal expression one of IGKV4-1’s most consistent transcriptional readouts.

The strongest signal is observed in head and neck squamous cell carcinoma (HNSC), where IGKV4-1 mass-spec protein is repressed in tumor relative to normal tissue. In most cancer types IGKV4-1 is over-expressed in tumor, although a few such as HNSC and COAD show the opposite, repressed pattern.

HNSC, COAD, and PDAC are the cancer types where IGKV4-1 tumor–normal differential expression is most reproducible.

mass-spec protein tumor vs normal associations by lineage

Ranked by sampling consensus. Fold-change is the tumor-versus-normal difference in IGKV4-1 mass-spec protein (log₂); positive values indicate higher expression in tumor. p-values are from the differential-expression test.

Lineage	Gender	Stage	Fold-change	p	Sampling consensus
HNSC	All	IV	−1.087	<.001	11	view →
COAD	Male	IV	−1.070	<.001	11	view →
PDAC	Female	All	+0.799	.001	4	view →
CCRCC	Male	All	+0.434	<.001	4	view →
LUAD	Female	All	−0.304	.025	2	view →

Pink = over-expressed in tumor, green = repressed in tumor. Showing the 5 strongest of 5 lineages.

Exploration

Same gene, other analysis: IGKV4-1 RNA expression & survival · all IGKV4-1 data types