Testing KIFC1 dependence across cancer types. Is cell survival more dependent on centrosome clustering or Survivin expression?

Kinesin family member C1 (KIFC1) is a motor protein that helps crosslink microtubules, transports cargo such as vesicles to the cell nucleus, and promotes accurate chromosome alignment and segregation during mitosis in healthy cells. In cancer, however, KIFC1 facilitates the clustering of supernumerary centrosomes, enabling the formation of pseudo-bipolar spindles and supporting the survival of cancer cells. KIFC1 has also been reported to promote the stability of the protein Survivin. Survivin, encoded by BIRC5, is an anti-apoptotic protein and mitotic regulator also frequently expressed in cancer. Both proteins are of therapeutic interest due to their roles in mitotic progression and survival. It is shown in the literature that many studies have focused greatly on breast cancer cell lines, but not as much compared to other cancer types, such as Ovarian, Colorectal and Central Nervous System (CNS) cancers. Therefore, this project aimed to investigate the dependency of cells on KIFC1 across Ovarian, Colorectal, and CNS cancer cell lines and determine whether KIFC1’s influence on centrosome clustering or Survivin expression plays a more critical role in cell survival. While KIFC1 has been well-studied in breast cancer, its function in other cancer types remains less understood. Six cell lines from the NCI-60 panel were selected: OVCAR8 and OVCAR4 (Ovarian), COLO205 and HT29 (Colorectal), and U251 and SNB-19 (CNS), representing cells with either high or low levels of centrosome amplification (CA) in each cancer type. Bioinformatic analysis using cBioPortal confirmed frequent alterations in KIFC1 and BIRC5 in cancers, with a weak correlation at the mRNA level. KIFC1 was knocked down using siRNAs, and the expression of KIFC1 and Survivin, as well as cell viability and apoptosis, were assessed using MTS assays and immunofluorescence staining. Other software, such as Fiji and GraphPad PRISM, was used to visualise, quantify, and interpret data findings from the experiments to fulfil the experimental design. This project demonstrates that many cancer cell lines depend on KIFC1 for proliferation and survival, highlighting it as a key therapeutic target. Survivin contributed variably, but overall cell viability was more strongly dependent on non-clustering cellular mechanisms. The KIFC1–Survivin relationship differed across cell types and appeared influenced by p53 status, with mutant p53 lines showing greater sensitivity to KIFC1 loss, whereas wild-type p53 lines showed resistance. In CNS cancers, apoptosis was the primary driver of reduced cell viability. cBioPortal analyses further confirmed the clinical relevance of KIFC1 and Survivin, supporting their combined targeting at the protein level. These findings highlight both the therapeutic promise and complexity of disrupting the KIFC1–Survivin axis in cancer and support further studies targeting KIFC1 therapeutically, including the development of Proteolysis-Targeting Chimaeras (PROTACs) to target KIFC1 across various cancer types.