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XAF1 / XIAP-associated factor 1 · IHC design guide
Design Immunohistochemistry for XAF1
Plan XAF1 staining in paraffin sections using cytoplasmic tissue staining as the main reference pattern (HPA tissue IHC). Compare controls and interpret intensity cautiously because antibody staining has low consistency with RNA expression (HPA tissue IHC).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
XAF1 Immunohistochemistry Experimental Design Guide
Expected localisation, validated protocols, controls and antibodies — the at-a-glance facts below, then the full design guide.
Must know before staining
| Expected localisation | Cytoplasmic tissue staining (HPA tissue IHC); nuclear location also reported (UniProt) | |
| Staining pattern | Cytoplasmic staining in most tissues, including glandular cells (HPA tissue IHC) | |
| Antigen retrieval | EDTA pH 8.0 HIER, heat-mediated (datasheet A03432-1) | |
| Positive control | Duodenum+4 more · see all | |
| Negative control | Adipose tissue+4 more · see all |
Important caveats
Reasons your staining may differ from the expected pattern.
| Fixation | Matched tissue-IHC evidence does not establish the fixation claim. Validate the specimen-specific method before use. (selected-SKU IHC image A03432-1) | |
| Caveat | Antibody staining has low consistency with RNA expression (HPA tissue IHC) | |
| Regulation | Often down-regulated in cancer cell lines (UniProt) | |
| Isoform / epitope | 7 isoforms; no processing annotated; epitope coverage unknown (UniProt) |
Section 1
Recommended XAF1 IHC & IF Protocols
The catalog antibody’s IHC-P protocol (datasheet: A03432-1) is followed by published XAF1 protocols for gastric cancer, renal cancer, and neuroblastoma specimens (PMC3695092; PMC3087333; PMC5085151).
| Sample | Paraffin-embedded human lung cancer tissue; fixative not specified (datasheet A03432-1) |
| Fixation | Image fixative and duration unreported (datasheet A03432-1); verify before use. |
| Sectioning | 4–5 µm sections on charged slides (standard) |
| Deparaffinisation | Xylene, graded ethanol series to water (standard) |
| Antigen retrieval | Heat retrieval: EDTA pH 8.0 (datasheet A03432-1); 20 min, 95–100 °C (standard) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet A03432-1) |
| Primary antibody | Rabbit anti-XAF1, 2-5 μg/ml (datasheet A03432-1) |
| Primary incubation | Overnight at 4 °C (datasheet A03432-1) |
| Detection | HRP-conjugated secondary, DAB chromogen (datasheet A03432-1) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | XAF1-positive staining in glandular cells of duodenum (HPA tissue IHC: High). HPA tissue profile: Cytoplasmic expression in most tissues. No signal in the no-primary control. |
💡Decision noteStart with EDTA pH 8.0 heat retrieval for the catalog antibody (datasheet: A03432-1). The published protocols used citrate, pressure cooking, or high pH buffer (PMC3695092; PMC3087333; PMC5085151).
Section 2
What Is the Expected XAF1 Staining Pattern?
XAF1 staining in paraffin sections is expected mainly in the cytoplasm, including glandular cells and kidney tubule cells with high reported staining (HPA tissue IHC). UniProt also places XAF1 in the nucleus and mitochondrion, with no transmembrane segment (UniProt Q6GPH4). The tissue IHC profile is Approved, but antibody staining has low consistency with RNA expression data; treat the pattern as a guide, not a definitive identity test (HPA tissue IHC).
| Distinct cytoplasmic staining in duodenal glands or kidney tubules, with little staining in adjacent negative cells. | This fits the reported high staining in duodenal glandular cells and kidney tubule cells, and the mainly cytoplasmic tissue profile (HPA tissue IHC). Check both cell identity and compartment before scoring a section as positive (standard IHC practice). |
| Predominantly nuclear staining with little cytoplasmic signal in a paraffin section. | This differs from the mainly cytoplasmic tissue IHC profile (HPA tissue IHC). Nuclear XAF1 remains biologically plausible (UniProt Q6GPH4), and nucleoplasmic signal is supported in ICC/IF (HPA subcellular); compare a positive tissue and antibody controls before calling the IHC pattern specific (standard IHC practice). |
| A sharp membrane rim or extracellular deposit is the dominant signal. | Neither pattern follows the reported cytoplasmic tissue staining (HPA tissue IHC) or the no-transmembrane topology (UniProt Q6GPH4). Consider nonspecific binding or detection artefact, then inspect a matched negative control and repeat with optimized washing (standard IHC practice). |
| Strong colour appears in an HPA-negative cell population, or colour is spread diffusely across the section. | Examples of reported undetected populations are adipocytes and lung alveolar cells (HPA tissue IHC). Staining there warrants checks for cross-reactivity, endogenous detection activity, or background; an HPA 'not detected' result is not proof that every specimen must be blank (HPA tissue IHC; standard IHC practice). |
| No cellular signal appears in a duodenal or kidney section used as a positive control. | HPA reports high staining in duodenal glandular cells and kidney tubule cells (HPA tissue IHC). If tissue integrity is adequate, review staining reagents, retrieval, primary-antibody conditions, and detection before interpreting an experimental negative (standard IHC practice). |
💡Expected XAF1 appearanceCall a paraffin IHC result positive when identifiable glandular or kidney tubule cells show clear, mainly cytoplasmic staining consistent with their reported High level (HPA tissue IHC); a dominant membrane rim, extracellular deposit, or uniform tissue haze should prompt artefact checks (UniProt Q6GPH4 topology; standard IHC practice).
| Tissue and cell selection | HPA reports High staining in duodenum, rectum, small intestine, thyroid gland, testis Leydig cells, and kidney tubule cells; adipocytes, lung alveolar cells, and several other listed populations were not detected (HPA tissue IHC). Choose controls by the named cell population, since a whole tissue can contain several cell types (standard IHC practice). |
| Compartment and application | Tissue IHC is mainly cytoplasmic (HPA tissue IHC), while supported ICC/IF localization is nucleoplasmic and mitochondrial (HPA subcellular); UniProt also lists cytoplasm, nucleus, and mitochondrion (UniProt Q6GPH4). Record the application and cellular context when comparing patterns. |
| Antibody evidence and transcript comparison | The listed antibody, HPA057302, is IHC Approved and ICC Supported (HPA antibodies). HPA describes low consistency between tissue antibody staining and RNA expression, despite low RNA tissue specificity (HPA tissue IHC); RNA abundance alone is an uncertain tie-breaker for a disputed stain. |
| Isoforms, topology, and processing | UniProt lists 7 isoforms, one annotated chain spanning residues 1–301, no signal peptide or propeptide, and no transmembrane segment (UniProt Q6GPH4). These annotations do not establish which isoforms the IHC antibody detects or how retrieval affects its epitope. |
| IF/ICC Q: Should nuclear or mitochondrial fluorescence match paraffin IHC? | A: Supported ICC/IF localization is mainly nucleoplasmic and mitochondrial, while tissue IHC is mainly cytoplasmic (HPA subcellular; HPA tissue IHC). Interpret each application against its own validated pattern; this section supplies no IF/ICC protocol. |
| Situation | Likely cause | Next action |
|---|---|---|
| Positive-control glandular or tubule cells show no stain. | The control misses its expected high-staining cells, or the staining run failed (HPA tissue IHC; standard IHC practice). | Confirm the named cells are present; then review reagent sequence, detection controls, retrieval, and the validated primary-antibody conditions before scoring test sections (standard IHC practice). |
| Nuclear signal dominates while cytoplasmic IHC signal is weak. | The pattern differs from HPA tissue IHC, although nuclear localization is reported by UniProt and supported by ICC/IF (HPA tissue IHC; UniProt Q6GPH4; HPA subcellular). | Record nuclear and cytoplasmic staining separately; compare the same run with an HPA-positive cell population and an appropriate negative control before assigning specificity (standard IHC practice). |
| Adipocytes or lung alveolar cells stain strongly. | These populations were reported as not detected (HPA tissue IHC); cross-reactivity or endogenous detection activity is possible (standard IHC practice). | Inspect primary-omission and detection controls, then compare staining in a high-staining reference population; avoid treating a single unexpected positive as confirmed XAF1 (standard IHC practice). |
| Uniform brown haze obscures cell borders. | Diffuse background can arise from insufficient blocking or washing, or excessive detection signal (standard IHC practice). | Use matched controls to locate the background source; adjust blocking, washing, or detection conditions while preserving a clear positive-control signal (standard IHC practice). |
| Colour concentrates on edges, folds, or extracellular material. | Those distributions do not match the mainly cytoplasmic tissue profile (HPA tissue IHC); section artefact or nonspecific signal is possible (standard IHC practice). | Assess intact, flat areas and a matched negative control; exclude deposits and damaged regions from cellular scoring (standard IHC practice). |
| Staining disagrees with an RNA-based expectation. | HPA explicitly reports low consistency between antibody staining and RNA expression data for this Approved tissue profile (HPA tissue IHC). | Report the observed cell type and compartment alongside the RNA discrepancy; rely on staining controls and independent evidence before making a target-specific conclusion (HPA tissue IHC; standard IHC practice). |
Experiment evidence
IHC & IF images showing XAF1 staining
A03432-1 · IHCIHC analysis of XAF1 using anti-XAF1 antibody (A03432-1). XAF1 was detected in a paraffin-embedded section of human lung cancer tissue. Heat
A03432-1 · IHCIHC analysis of XAF1 using anti-XAF1 antibody (A03432-1). XAF1 was detected in a paraffin-embedded section of human placenta tissue. Heat me
A03432 · IHCImmunohistochemical staining of human spleen tissue using XAF-1 antibody at 2 μg/mL.
A03432 · IFImmunofluorescence of XAF-1 in Human Spleen tissue with XAF-1 antibody at 10 μg/mL.
PA1218 · IFIF analysis of XAF1 using anti-XAF1 antibody (PA1218). XAF1 was detected in an immunocytochemical section of U2OS cells. Enzyme antigen retr
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000132530-XAF1/tissue/cerebral+cortex#imid_16202103
HPA · Thyroid glandHuman Protein Atlas IHC, Thyroid gland. Source: https://www.proteinatlas.org/ENSG00000132530-XAF1/tissue/thyroid+gland#imid_16202071
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000132530-XAF1/tissue/colon#imid_16202037
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000132530-XAF1/tissue/liver#imid_16202046
![HPA ICC-IF BJ [Human fibroblast] — XAF1 (HPA057302)](https://images.proteinatlas.org/57302/1368_H6_1_blue_red_green.jpg)
HPA · ICC-IF BJ [Human fibroblast]Human Protein Atlas immunofluorescence, BJ [Human fibroblast], antibody HPA057302; green = XAF1, blue = nucleus, red = microtubules.
![HPA ICC-IF BJ [Human fibroblast] — XAF1 (HPA057302)](https://images.proteinatlas.org/57302/1368_H6_2_blue_red_green.jpg)
HPA · ICC-IF BJ [Human fibroblast]Human Protein Atlas immunofluorescence, BJ [Human fibroblast], antibody HPA057302; green = XAF1, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for XAF1 IHC & IF
🧪Run duodenum first: its glandular cells should stain (HPA: High in duodenal glandular cells). Use cervix glandular cells as a negative tissue (HPA: Not detected in cervical glandular cells); on the duodenum slide, assess non-glandular cells for background against the no-primary control rather than assuming they lack XAF1 (HPA: duodenum row reports glandular cells only).
Positive control tissue: Duodenum (Glandular cells, HPA High)
Negative control tissue: Adipose tissue (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show XAF1 in BJ [Human fibroblast], SK-MEL-30, U2OS, with annotated localisation: Nucleoplasm (supported), Mitochondria (supported) (HPA subcellular).
Technical controls: Include no-primary (secondary-only) and matched rabbit immunoglobulin isotype controls (selected-SKU caption: rabbit primary); use XAF1-knockout material, if available, as a biological specificity control (standard IHC practice). Block endogenous peroxidase in duodenum before HRP/DAB detection (selected-SKU caption: HRP/DAB; standard IHC practice).
⚠️Feasibility: A target-specific fixation window or fixation effect is unreported, and the selected-SKU tissue-IHC caption does not state a fixative (selected-SKU caption: fixative not stated). The caption reports heat retrieval in EDTA at pH 8.0 for a paraffin section, but does not establish whether retrieval is required for duodenum (selected-SKU caption: lung cancer tissue, EDTA retrieval). Neither frozen sections nor IF/ICC is established as easier by the supplied evidence; duodenal glandular background should be judged against controls (HPA: High in duodenal glandular cells; standard IHC practice).
HPA tissue IHC evidence for XAF1
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Approved — Low consistency between antibody staining and RNA expression data.). Rows are taken directly from the HPA tissue chart — click any row's HPA link to view the source.
Positive expression · recommended positive controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Duodenum | Glandular cells | High | Protein (IHC) | HPA → |
| Endometrium | Glandular cells | Medium | Protein (IHC) | HPA → |
| Kidney | Cells in tubules | High | Protein (IHC) | HPA → |
| Rectum | Glandular cells | High | Protein (IHC) | HPA → |
| Small intestine | Glandular cells | High | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Adipose tissue | Adipocytes | Not detected | Protein (IHC) | HPA → |
| Cerebellum | Cells in granular layer | Not detected | Protein (IHC) | HPA → |
| Cervix | Glandular cells | Not detected | Protein (IHC) | HPA → |
| Lung | Alveolar cells | Not detected | Protein (IHC) | HPA → |
| Lymph node | Non-germinal center cells | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced XAF1 IHC Tips
Use compartment, cell type, and matched controls to troubleshoot XAF1 staining in paraffin sections; assess IF/ICC separately.
How should I troubleshoot weak XAF1 staining after antigen retrieval?
Start with heat-mediated retrieval in EDTA at pH 8.0 for paraffin sections (datasheet A03432-1). The selected XAF1 image used this retrieval before incubation with 2 μg/ml antibody overnight at 4°C (datasheet A03432-1). If staining is weak, compare retrieval heating and cooling conditions across matched sections while holding antibody concentration and detection constant (standard IHC practice). Include a tissue with documented XAF1 staining, such as kidney tubule cells, and inspect morphology for retrieval damage (HPA: High in kidney tubule cells; standard IHC practice). A stronger signal accompanied by damaged tissue does not establish better specific staining (standard IHC practice).
Could fixation explain variable XAF1 staining between paraffin blocks?
Target-specific sensitivity of XAF1 staining to fixation is unknown from the supplied evidence; the selected paraffin-section caption does not state a fixative (datasheet A03432-1). Record each block's fixative and fixation interval, then compare sections processed with the same retrieval and detection conditions (standard IHC practice). Prolonged or inconsistent fixation can change epitope accessibility in IHC generally, so assess tissue preservation and staining together (standard IHC practice). Use heat-mediated EDTA retrieval at pH 8.0 as the documented starting condition (datasheet A03432-1). Do not assign a block-to-block difference to XAF1 biology until processing differences and controls have been examined (standard IHC practice).
Should XAF1 staining be cytoplasmic, nuclear, or mitochondrial?
Evaluate XAF1 staining by compartment and cell type: tissue IHC commonly shows cytoplasmic expression, while the protein is also annotated in nuclei and mitochondria (HPA tissue IHC: cytoplasmic expression in most tissues; UniProt Q6GPH4: subcellular location). Nucleoplasm and mitochondria are supported locations in cell imaging (HPA subcellular: supported locations). The selected paraffin-section example demonstrates XAF1 detection in human lung cancer tissue but does not establish one exclusive compartment (datasheet A03432-1). Compare nuclear counterstain boundaries with the chromogenic deposit, and score nuclear and cytoplasmic signal separately when both are present (standard IHC practice). Treat a compartment shift as a finding to validate with controls and matched conditions (standard IHC practice).
Could XAF1 isoforms explain inconsistent staining across specimens?
XAF1 has 7 annotated isoforms, so epitope coverage matters when comparing antibodies or specimens (UniProt Q6GPH4: isoforms 1–7). The supplied caption establishes staining with A03432-1 in paraffin-embedded human lung cancer tissue, but supplies no epitope coordinates or isoform-specific reactivity (datasheet A03432-1). Check the antibody's documented immunogen or epitope before attributing discordant staining to an isoform, and use a second independently characterized epitope when available (standard IHC practice). XAF1 has no annotated transmembrane segment or glycosylation sites, but those annotations do not identify the antibody's binding site (UniProt Q6GPH4: topology and glycosylation). Keep retrieval and scoring conditions matched during antibody comparisons (standard IHC practice).
How can I investigate XAF1 localisation by multiplex IF?
For a separate IF/ICC experiment, pair XAF1 with a marker identifying the cell population being examined and a nuclear counterstain, then inspect overlap within individual cells (standard IF practice). XAF1 is intracellular, with cytoplasmic, nuclear, and mitochondrial locations reported; its sequence has no annotated transmembrane segment (UniProt Q6GPH4: subcellular location and topology). Permeabilise to expose the intracellular epitope, adjusting detergent conditions against morphology and the antibody's documented epitope accessibility (standard IF practice). Choose fluorophores and imaging channels after checking tissue autofluorescence, using an unstained section and single-label controls for multiplex separation (standard IF practice). Nucleoplasm and mitochondria are supported locations in cell imaging (HPA subcellular: supported locations).
What should I check when XAF1 DAB staining is diffuse?
Begin with a no-primary control and inspect whether diffuse color persists after the chromogenic detection steps (standard IHC practice). The selected paraffin-section example used 10% goat serum block, peroxidase-conjugated secondary detection, and DAB; these document that image's workflow, not the cause of background in another specimen (datasheet A03432-1). Include an endogenous peroxidase block, check secondary-antibody background, and optimize washing before increasing primary-antibody concentration (standard IHC practice). The documented primary condition was 2 μg/ml overnight at 4°C, which provides a starting point for matched-section titration (datasheet A03432-1). Judge improvement against preserved cell morphology and compartment-resolved signal (standard IHC practice).
How should I quantify XAF1 across heterogeneous tissue sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and tissue region before scoring, then record the percentage of positive cells and intensity or calculate an H-score from those measurements (standard IHC practice). Score nuclear and cytoplasmic compartments separately when both occur, because XAF1 has reported locations in each (UniProt Q6GPH4: subcellular location). For spatial comparisons, report positive-cell density per mm² of viable tissue and normalize to the number of evaluable cells or analyzed tissue area, as appropriate (standard IHC practice). Keep threshold, imaging settings, retrieval, and batch controls consistent across sections (standard IHC practice). Report cell-type-specific results because documented XAF1 staining varies among tissue cell populations (HPA tissue IHC: positive and not-detected cell populations).
How can I distinguish true XAF1 staining from artefact?
Ask whether signal falls within intact cells and a plausible XAF1 compartment, then compare its distribution with nuclear counterstain and tissue morphology (UniProt Q6GPH4: cytoplasm, nucleus, mitochondrion; standard IHC practice). Cell identity matters: HPA reports high staining in kidney tubule cells but no detection in lung alveolar cells, while its antibody staining has low consistency with RNA data (HPA tissue IHC). Exclude section-edge concentration, necrotic regions, and staining reproduced in a no-primary control before calling weak DAB signal positive (standard IHC practice). Endogenous peroxidase can mimic chromogenic signal, so examine the peroxidase-block control and detection controls (standard IHC practice). Confirm unexpected patterns with an independent antibody or orthogonal expression evidence (standard IHC practice).
Boster reagents
Best XAF1 / XIAP-associated factor 1 IHC Antibodies
Anti-XAF1 antibodies have image data for human tissue IHC (A03432-1 and A03432 IHC captions), human tissue IF (A03432 IF caption), and human cell IF/ICC (PA1218 IF caption).
Real IHC data
Anti-XAF1 Antibody ®
Cat # A03432-1
Real IHC data
Anti-XAF-1 Antibody
Cat # A03432
Real IF data
Anti-XIAP-associated factor 1 XAF1 Antibody ®
Cat # PA1218
A03432-1 shows IHC in paraffin sections of human lung cancer, placenta, and thyroid cancer (A03432-1 IHC captions). A03432 shows human spleen IHC and IF (A03432 image captions); PA1218 shows IF/ICC in human U2OS cells (PA1218 IF caption).
Which to pick: For tissue IHC, choose A03432-1 when working with human paraffin sections (A03432-1 applications and IHC captions); its captions do not report the fixative (A03432-1 IHC captions). For IF/ICC in human cells, choose PA1218, a polyclonal antibody with a U2OS IF image (PA1218 dilution_raw and IF caption). For work spanning human and mouse samples, consider A03432 because both species and IHC-P/IF are listed, while its supplied images show human spleen only (A03432 reactivity, applications, and image captions).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry Q6GPH4 (XAF1_HUMAN, XIAP-associated factor 1).
- Human Protein Atlas. XAF1 tissue IHC expression (reliability: Approved).
- Human Protein Atlas. XAF1 subcellular location (ICC-IF): Mainly localized to the nucleoplasm and mitochondria..
- Human Protein Atlas. XAF1 antibody validation summary (1 antibodies).
- SARM1 deficiency up-regulates XAF1, promotes neuronal apoptosis, and accelerates prion disease. The Journal of experimental medicine 2019 — PMC6446871.
- Circulating Methylated XAF1 DNA Indicates Poor Prognosis for Gastric Cancer. PloS one 2013 — PMC3695092.
- Down-regulation of the pro-apoptotic XIAP associated factor-1 (XAF1) during progression of clear-cell renal cancer. BMC cancer 2009 — PMC3087333.
- XAF1 promotes neuroblastoma tumor suppression and is required for KIF1Bβ-mediated apoptosis. Oncotarget 2016 — PMC5085151.
- PubMed PMID:11175744 — UniProt-cited evidence.
- PubMed PMID:17570219 — UniProt-cited evidence.
- PubMed PMID:14702039 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for XAF1 (XIAP-associated factor 1). Expected localisation Cytoplasmic tissue staining (HPA tissue IHC); nuclear location also reported (UniProt). Antigen retrieval: EDTA pH 8.0 HIER, heat-mediated (datasheet A03432-1). Validated IHC antibody: A03432-1 at 2-5 μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Duodenum (Glandular cells); negative Adipose tissue. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded human lung cancer tissue; fixative not specified (datasheet A03432-1); 2. Fixation: Image fixative and duration unreported (datasheet A03432-1); verify before use.; 3. Sectioning: 4–5 µm sections on charged slides (standard); 4. Deparaffinisation: Xylene, graded ethanol series to water (standard); 5. Antigen retrieval: Heat retrieval: EDTA pH 8.0 (datasheet A03432-1); 20 min, 95–100 °C (standard); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet A03432-1); 8. Primary antibody: Rabbit anti-XAF1, 2-5 μg/ml (datasheet A03432-1); 9. Primary incubation: Overnight at 4 °C (datasheet A03432-1). Watch for: Fixation: Matched tissue-IHC evidence does not establish the fixation claim. Validate the specimen-specific method before use. (selected-SKU IHC image A03432-1); Caveat: Antibody staining has low consistency with RNA expression (HPA tissue IHC); Isoform / epitope: 7 isoforms; no processing annotated; epitope coverage unknown (UniProt); Regulation: Often down-regulated in cancer cell lines (UniProt). Evidence: UniProt Q6GPH4, HPA tissue IHC · Approved, HPA ICC-IF · Mainly localized to the nucleoplasm and mitochondria., Datasheet A03432-1, PMC3695092, PMC3087333. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/XAF1/immunohistochemistry-ihc-guide.