The development of high-throughput sequencing and bioinformatics has led to an increase in the use of bioinformatics techniques to find novel biomarkers involved in tumor progression, survival, or prognosis of malignancies, which may greatly help with early diagnosis and prognosis assessment in malignant tumors[15-17]. It is challenging to timely improve the prognosis of patients with aggressive LUAD with a single targeted method or medication therapy due to the disease's rapid progression. In order to facilitate early intervention, it may be useful to build predictive models employing genes related with prognosis. But there aren't enough of these marks. As a result, it is necessary to screen for additional biomarkers with strong predictive performance so that they can be added to the candidate list.
Anoikis, a form of programmed cell death, happens when cells detach from the appropriate extracellular matrix, interfering with integrins' ability to adhere[18]. It is a crucial mechanism for preventing the growth or attachment of dysplastic cells to the wrong matrix. Anoikis is necessary for tissue homeostasis and development because it prevents detached epithelial cells from settling in other places[19]. Normal epithelial cells normally lose vital survival components and die through a process known as anoikis when they separate, however LUAD metastatic tumor cells develop resistance to anoikis, allowing them to start healing distant from the main lesion[20]. Anoikis dysregulation is presently of great interest to the scientific community because anchorage-dependent growth and the epithelial-mesenchymal transition, two characteristics linked to anoikis resistance, are essential steps in tumor progression and the metastatic dissemination of cancer cells[21-23]. The idea of targeting anoikis-related genes to stop LUAD progression and metastasis is highlighted by the fact that LUAD can acquire anoikis resistance through a variety of mechanisms. The complicated interaction of numerous factors impacting anoikis resistance in tumor pathophysiology is shown in polygenic analysis. Therefore, in the era of precision medicine for cancer, this polygenic method might enable characterization of tumor biology to enhance clinical decision-making.
In this study, we identified robust risk score features containing 8 genes, namely BUB1, CDKN3, IL17A, KIF18A, PCNA, PLK1, UBE2C and TIMP1. Previous studies have described certain associations between genes and the tumorigenesis and pathogenesis of cancer. A conserved mitotic Serine/Threonine kinase called BUB1 (budding uninhibited by benzimidazole 1) was initially discovered in budding yeast[24]. Bub1 plays a function in APC/C activation as well as SAC signaling, chromosomal alignment, and alignment[25]. CDKN3 (Cyclin-dependent kinase inhibitor-3) is a dual-specificity protein tyrosine phosphatase of the CDC14 group. Initially known as CDK-Associated Phosphatase(KAP), CDKN3 was discovered from a HeLa cDNA library as a CDK2 binding protein through a yeast two-hybrid screen[26]. The expression of CDKN3, which regulates cell division and is more prominent during the mitotic phase, inhibits the CDK-driven cell cycle, a crucial step in the development of cancer cells[27]. Rouvier et al. first identified IL-17A at the transcriptional level in a rodent T-cell hybridoma that resulted from the union of a mouse cytotoxic T cell clone with a rat T cell lymphoma in 1993. Through the production of IL-6, which in turn activates the oncogenic transcription factor signal transducer and activator of transcription 3 (STAT3) and upregulates pro-survival and pro-angiogenic genes in tumors, IL-17A can also accelerate tumor growth in vivo[28]. Kinesin-8 motors consist of KIF18A, KIF18B, and KIF19. The N-kinesin-8 molecular motor protein, also known as the kinesin family member 18A (KIF18A) protein, is mostly found in the cytoplasm and nucleus and has a molecular weight of 100 kDa. By controlling microtubule dynamics, chromosomal aggregation, and cell division, KIF18A physiologically ensures the proper development of cell mitosis. Previous studies have demonstrated that deregulation of KIF18A expression may have an impact on chromosomal segregation and/or instability, causing tumors to develop[29-31]. A DNA polymerase auxiliary protein known as PCNA, which is crucial for DNA replication, has the ability to extend DNA polymerase. It is connected to the process of cell division, takes part in DNA synthesis, and significantly regulates the cell cycle. PCNA and tumor cell proliferation are tightly associated, and a cell's expression of PCNA may indicate whether or not it is proliferating[32-33]. A crucial regulator of mitosis and cytokinesis in eukaryotes is PLK1 (Polo-like kinase 1), the prototype member of the polo-like family of serine/threonine kinases. The course of mitosis, centrosome assembly, chromosomal segregation, spindle elongation, and cytokinesis are all crucial processes that it affects[34]. UBE2C, an E2 ubiquitin-conjugating enzyme, collaborates with APC/C to play a crucial part in the ubiquitination system. It helps the cell cycle move from the M phase to the G1 phase by participating in the breakdown of mitotic cyclin B[35]. TIMP1 is one of the four members of the matrix metalloproteinase (MMP) inhibitor family (TIMP1, TIMP2, TIMP3 and TIMP4). TIMP1's primary job is to prevent extracellular matrix degradation caused by MMPs[36]. Studies conducted in vitro have shown that overexpression of TIMP1 can significantly increase the expression of genes related to signal transduction, apoptosis, and proliferation[37]. TIMP1 also showed anti-apoptotic action and was discovered to impair tumor cell sensitivity to a number of anticancer treatments by activating downstream pathways. It has been shown, in particular, that TIMP1 may bind to the CD63/integrin-1 complex and have anti-apoptotic effects[38].
The tumor microenvironment (TME), which is composed of the ECM, stroma cells, tumour vasculature, and different immune system cells, supports the onset and spread of cancer[39]. Recently, immunotherapy has been found as a new treatment option for this condition. Growing evidence indicates that the presence of innate immune cells in the tumor microenvironment, such as macrophages, neutrophils, dendritic cells, innate lymphoid cells, myeloid-derived suppressor cells, and natural killer cells, as well as adaptive immune cells such as T cells and B cells, can promote tumor development[40]. The milieu that develops from cross-talk between cancer cells and the proximal immune cells eventually encourages the growth and metastasis of tumors[41]. In the high-risk group with poor survival, the level of Plasma cells, T cells CD4 and Macrophages was significantly upregulated, suggesting its crucial role in the development of LUAD.
Given the variety of cells, anoikis studies carried out at the single-cell level may more properly reflect the effect of ANRGs on the course and prognosis of LUAD patients, even though our riskScore and the nomogram built on it have greater predictive performance. Additionally, a bigger sample size is needed for the calibration of the prediction model due to the small amount of data in this investigation.
In conclusion, our model based on eight genes can accurately predict the survival of LUAD patients, and the nomogram based on the model can assist medical professionals in creating customized LUAD treatments in clinical settings. Future investigations into the molecular pathways connected to this trait and prospective randomized clinical trials will be crucial from a clinical standpoint and could offer a blueprint for precision medicine.