HT55

HT55 is a human rectal adenocarcinoma cell line established from the primary rectal tumor of a 54-year-old Caucasian female. The line grows as an adherent monolayer with epithelial-like morphology. HT55 carries multiple heterozygous and homozygous loss-of-function mutations in the APC (adenomatous polyposis coli) tumor suppressor gene, including p.Gln1131Ter, p.Gln1303Ter, p.Arg1463Ser, p.Asn581Tyr, and p.Lys241Ter (all heterozygous), as well as a homozygous p.Arg213Leu substitution. This mutational profile renders HT55 a biologically relevant model of APC-driven colorectal carcinogenesis, reflecting the canonical WNT pathway dysregulation that drives the majority of human colorectal cancers.

HT55 is widely used in colorectal cancer research for studies of WNT/β-catenin signalling, APC tumor suppressor function, drug sensitivity and resistance, and preclinical evaluation of targeted agents against components of the WNT pathway. The line is suitable for in vitro pharmacological assays and xenograft studies in immunocompromised mouse models, providing an adherent, tractable in vitro platform for mechanistic and translational colorectal cancer research. The presence of multiple APC truncation mutations makes HT55 representative of the microsatellite-stable, chromosomally unstable colorectal cancer subtype commonly driven by APC loss-of-function.

37°C, 5% CO₂, humidified atmosphere.

1. Confirm that the vial remains deeply frozen upon delivery, as cells are shipped on dry ice to maintain optimal temperatures during transit.

2. Upon receipt, either store the cryovial immediately at temperatures below -150°C to ensure the preservation of cellular integrity, or proceed to step 3 if immediate culturing is required.

3. For immediate culturing, swiftly thaw the vial by immersing it in a 37°C water bath with clean water and an antimicrobial agent, agitating gently for 40-60 seconds until a small ice clump remains.

4. Perform all subsequent steps under sterile conditions in a flow hood, disinfecting the cryovial with 70% ethanol before opening.

5. Carefully open the disinfected vial and transfer the cell suspension into a 15 ml centrifuge tube containing 8 ml of room-temperature culture medium, mixing gently.

6. Centrifuge the mixture at 300 x g for 3 minutes to separate the cells and carefully discard the supernatant containing residual freezing medium.

7. Gently resuspend the cell pellet in 10 ml of fresh culture medium. For adherent cells, divide the suspension between two T25 culture flasks; for suspension cultures, transfer all the medium into one T25 flask to promote effective cell interaction and growth.

8. Adhere to established subculture protocols for continued growth and maintenance of the cell line, ensuring reliable experimental outcomes.

For long-term preservation, place vials in vapor-phase liquid nitrogen at about −150 to −196 °C. Storage at −80 °C is acceptable only as a short interim step before transfer to liquid nitrogen.

Cryopreserved cell lines are shipped on dry ice in validated, insulated packaging with sufficient refrigerant to maintain approximately −78 °C throughout transit. On receipt, inspect the container immediately and transfer vials without delay to appropriate storage.

At Cytion, we stand behind the quality and viability of our products. We guarantee that our cells will be viable at the start of culture for 60 days after shipment from our facilities. We assure that all materials conform to the specifications described in the Certificate of Analysis and/or Product Sheet.

For full details, please refer to our Warranty Statement.