CaMMKs to control inammation, food intake, adipogenesis, and glucose metabo­lism. In addition, its role in carcinogenesis has been established. Since androgen­receptor hyperactivity contributes to prostate cancer, CaMKK2 is also overexpressed in this disease [48]. New evidence suggests that CAMKK2 knockdown causes ves­icle-trafcking disruption disturbances. Because CAMKK2 inuences organelle integrity and membrane transport, it sustains cell proliferation, which is compatible with the role of autophagy in cancer development [49].

growth by inuencing DNA replication, metastasis, and angiogenesis [60, 61]. The activation of hypoxia inducible factor 1 subunit alpha, which is known as HIF1A/ HIF-1α, occurs in hypoxic conditions and improves the proliferation and survival of prostate cancer cells [62, 63]. Results show that HIF1A has a dual function in cancer regulation of autophagy [64]. By inuencing autophagy, HIF1A promotes tumor growth in prostate cancer. Autophagy induction occurs at the transcriptional level, where HIF1A binds to the Atg5 promoter and increases Atg5 expression. For tumor formation in nude mice, the HIF1A-ATG5-autophagy axis is crucial [65]. For upstream mediators involved in autophagy induction and the enhancement of pros­tate cancer progression, ATG5 could be a target [66]. Fibroblast growth factors (FGFs) are thought to have a wide variety of biological roles, such as regulating metabolism, development, angiogenesis, differentiation, and growth [67]. Metabolic homeostasis is linked to FGF21, which is released by the liver [68]. Reduced prolif­eration and survival rates are associated with downregulating FGF21, which may indicate an anti-tumor effect. Curiously, FGF21 slows the growth of prostate cancer by inducing autophagy and blocking the PI3K-AKT-MTOR axis [69]. Furthermore, there has been recent research on how an autophagic genetic signature affects pros­tate cancer susceptibility and prognosis. Using the Prostate adenocarcinoma (PRAD) dataset from The Cancer Genome Atlas (TCGA), Cheng and colleagues have discovered Differentially Expressed Autophagy-Related Genes (DEARGs), or differentially expressed autophagy-related genes. They found 16 DEARGs, 7 of which were linked to OS in prostate cancer patients. Furthermore, three prognostic genes (NPC1, BNIP3, and TP53) were linked to clinical features: increased levels of Niemann-Pick C1 protein (NPC1) and BCL2 interacting protein 3 (BNIP3) were strongly linked to advanced pathological T stages, and overexpression of NPC1 was substantially associated with higher International Society of Urological Pathology (ISUP) grades [70]. More than 20 Autophagy-Related Genes (ARGs) inuencing disease-free survival (DFS) associated with T status, N status, and Gleason score were also demonstrated in a study by Hu and colleagues [71]. The Human Autophagy Database retrieved the data; they compared the ARGs that were found to be differ­ently expressed with over 230 ARGs that were collected from the Cancer Genome Atlas (TCGA) database. The results corroborate earlier ndings from studies using biopsy samples. Indeed, studies have looked into how the expression of the four main autophagy proteins—LC3A, LC3B, Beclin 1, p62, and lactate dehydrogenase 5-LDH5—relates to the aggressiveness of cancer. When LDH5 levels were high and the Gleason score was high, it was because LC3A, LC3B, and p62 were highly expressed in the cytoplasm of the tumor cells (more than 50% of the cells in each region). In addition, there was a strong correlation between substantial Beclin-1 overexpression and extraprostatic invasion [72]; these results suggest that ARGs and phenotypical autophagy expression could be useful prognostic indicators.

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Once a tumor mass has formed, autophagy activation is critical for cancer cell sur­vival, despite the fact that it suppresses tumors in non-tumor cells and during early tumor cell formation. In order to achieve their higher energy rate and building block use, cancer cells exhibit an elevated metabolic demand. Adapting to metabolic deprivation, they increase autophagic ux and rely on energy supply [74]. As pros­tate cancer develops from normal to malignant tissue, research has revealed that STK11/LKB1 expression declines. Prostate carcinogenesis is dened histologically by a gradual progression from normal epithelium to invasive prostate cancer, as shown in high-grade prostate intraepithelial neoplasia (PIN). When using immuno­histochemistry, only normal or atrophic cells will display staining for STK11/LKB1 [75]. Dysplastic cells will not stain. Furthermore, it was demonstrated that stak11/ LKB1 expression inuenced the effect of p38MAPK inhibition on prostate cancer cell survival. Particularly, a treatment strategy based on p38MAPK inhibitors in conjunction with ADT may be benecial for prostate cancer patients lacking STK11/LKB1 expression. Patients with prostate cancer that express a lot of STK11/ LKB1 could benet from treatments that target the autophagic machinery or dual kinase inhibition, which targets both p38MAPK and AMPK.

metformin, an oral biguanide. Its autophagy-inhibiting effects are well-documented, and its method of action involves blocking mTOR through AMPK activation. This trigger is supposed to increase autophagic activity, however it instead blocks Beclin-1 and suppresses autophagy even after activating AMPK [80]. Nevertheless, metformin inhibits autophagy activity in a way that is reliant on environmental fac­tors. To that end, Chen and colleagues found that metformin may improve autoph­agy in prostate cancer cells in their most recent study. It has been demonstrated that metformin reduces cell proliferation by activating the AMPK system, which is linked to an increase in apoptotic activity and a larger autophagic ux [81]. Autophagy has multiple effects that determine cell viability, and these results are in line with those effects.

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activated [93]. Other molecular pathways that contribute to the progression of pros­tate cancer are also associated with autophagy’s anti- tumor effects [94]. An example of this would be the nding that overexpression of the hydroxysteroid 17-beta dehy­drogenase 4 gene enhances the growth and cancerous behavior of prostate cancer cells. Reduced prostate cancer progression is the result of HSD17B4 being acety­lated, which increases its breakdown by CMA [95]. Although autophagy is not involved in cell death in this scenario, it does lead to the degradation of a component that promotes the growth of prostate cancer.

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pathways. Breakdown of cytoskeletal and nuclear proteins, DNA fragmentation, cross-linking of proteins, creation of apoptotic bodies, production of ligands for phagocytic cell receptors, and absorption by phagocytic cells are all steps in this process that begins with caspase-3 cleavage. A parallel cell death process that does not rely on caspases is activated by the granzyme A pathway through damage to single-stranded DNA [105]. Figure4.2 shows the molecular prole of apoptosis.

Furthermore, the unique structural pathology mentioned earlier is the conse­quence of a number of biochemical variations that apoptotic cells exhibit, including protein cleavage, protein cross-linking, DNA disintegration, and phagocytic recog­nition [106]. The majority of cells express caspases in their inactive proenzyme form; when activated, these caspases can initiate a protease cascade by activating other procaspases. It is also possible for some procaspases to cluster and autoacti­vate. By provoking additional caspases, this proteolytic cascade speeds up the apop­totic signaling pathway, which in turn causes cells to die off quickly.

Fig. 4.2 The molecular prole of apoptosis (Biorender.com)

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inammation (caspase-1, -4, -5) [107, 108]. Not to mention, caspase-11 is known to control cytokine maturation and apoptosis in septic shock, caspase-12 is involved in endoplasmic-specic apoptosis and cytotoxicity caused by amyloid-β, caspase-13 is thought to be a gene specic to cattle, and caspase-14 is abundant in embryonic tis­sues but not in adult tissues [109–112]. Apoptotic cells also express and activate tissue transglutaminase, leading to extensive protein cross-linking [113]. Moreoevr, fragments of 180–200bp of DNA are also produced by endonucleases that are reli­ant on Ca2+ and Mg2+ [114]. Due to the ethidium bromide stain and ultraviolet light used in agarose gel electrophoresis, a distinctive “DNA ladder” may be seen. One such biochemical characteristic is the production of cell surface signals, which allow neighboring cells to quickly phagocytose apoptotic cells with little damage to the surrounding tissue. To do this, the normally inward-facing phosphatidylserine of the cell’s lipid bilayer is transferred to the outer layers of the plasma membrane for expression [115]. While phosphatidylserine externalization is a well-known phago­cyte recognition ligand, newer research has demonstrated that additional proteins may also be exposed on the surface of apoptotic cells during clearance. Two exam­ples are calreticulin and annexin I.