👤 Hammad Saleem

A plethora of factors contribute to cognitive impairment in Alzheimer's disease (AD), including neuroinflammation, synaptic dysfunction and gene alteration. In search of transcription factors controlling dysregulated genes in AD, we identified that the histone demethylase PHF2 (KDM7C) was a top-ranking candidate. Significant upregulation of PHF2 was found in AD human postmortem tissues, iPSC-derived neurons from AD patients, and a familial AD mouse model (5xFAD). ChIP-seq analysis and quantitative PCR profiling with bidirectional manipulation of Phf2 revealed that Phf2 regulated many genes critically involved in inflammatory pathways and neurodegeneration, including Stat3, Nfkbia, Nfkb2, Tnfrsf1a, Fgfr1, IL6st, Notch2, and Csf1. Knockdown of Phf2 in 5xFAD mice reduced the expression of inflammatory genes, leading to the substantial reduction of microglia/astrocyte activation and the restoration of glutamatergic synaptic function. Behavioral studies showed that Phf2 knockdown in 5xFAD mice significantly improved performance in the Barnes maze test, indicating a mitigation of spatial memory deficits. Our findings have revealed the epigenetic enzyme PHF2 as a regulator of neuroinflammatory processes in AD, linking its activity to both gene expression and cognitive outcomes. It suggests that targeting PHF2 could be a novel therapeutic approach for AD and other brain disorders involving neuroinflammation. Show less

Obesity is a highly complex, multifactorial disease influenced by dynamic interactions among genetic, epigenetic, environmental, and behavioral determinants that explicitly position genetics as the core. While advances in multi-omic integration have revolutionized our understanding of adiposity pathways, translation into personalized clinical nutrition remains a critical challenge. This review systematically consolidates emerging insights into the molecular and nutrigenomic architecture of obesity by integrating data from large-scale GWAS, functional epigenomics, nutrigenetic interactions, and microbiome-mediated metabolic programming. The primary aim is to systematically organize and synthesize recent genetic and genomic findings in obesity, while also highlighting how these discoveries can be contextualized within precision nutrition frameworks. A comprehensive literature search was conducted across PubMed, Scopus, and Web of Science up to July 2024 using MeSH terms, nutrigenomic-specific queries, and multi-omics filters. Eligible studies were classified into five domains: monogenic obesity, polygenic GWAS findings, epigenomic regulation, nutrigenomic signatures, and gut microbiome contributions. Over 127 candidate genes and 253 QTLs have been implicated in obesity susceptibility. Monogenic variants (e.g., Show less

Patients with inflammatory breast cancer (IBC) have aggressive biology and relatively inferior responses to standard-of-care (SOC) therapies. Understanding the efficacy of SOC therapies in IBC is critical to optimize outcomes. Our objective was to assess the progression-free survival (PFS) of metastatic hormone receptor-positive HER2-negative/low (HR+HER2-) IBC patients treated with CDK4/6 inhibitors (CDKIs) and hormonal therapy (HT). Data from 58 IBC patients with metastatic HR + /HER2- IBC from a single institution were reviewed. The medians (95% confidence intervals) of overall survival (OS), PFS, and time on treatment (ToT) from the time of CDKI initiation were reported via the Kaplan‒Meier method. Differences were tested by the log-rank test. We identified 58 patients (including 16 with de novo stage IV disease). The median OS, PFS, and ToT in the total cohort were 26 (16, 37), 7 (5, 10), and 7 (5, 10) months (mos), respectively. No differences were observed between pre-menopausal patients and postmenopausal patients. The OS, PFS, and ToT rates at the initial diagnosis of Stage III later developing metastatic breast cancer (MBC, N = 42) and de novo IV (N = 16) patients were 19 (15, 34) vs 34 (21, NR), 7 (5, 14) vs 9 (6, NR), and 6 (5, 10) vs 9 (4, NR) mos, respectively (ns). OS, PFS, and ToT in patients receiving CDKI in the first-line vs second-line metastatic setting were 27 (19, 44) vs 17 (12, 39), 7 (5, 15) vs 6 (3, NR), and 7 (5, 15) vs 6 (3, 20) mos, respectively (ns). Among the patients initially diagnosed with stage III disease later progressing to MBC, brain metastases were observed in 12/42 patients. Thirty-eight patients underwent genomic testing either before CDKI treatment (N = 21) or at progression (N = 17). Among the 38 patients who underwent genomic testing, 34 had mutations, most commonly in TP53, PIK3CA, FGFR1, CCND1, and ARID1A. ESR1 mutations were present in 0% of the samples tested prior to CDKI treatment, and 29% of the samples tested at progression. Patients with metastatic HR+HER2- IBC demonstrated a shorter time on treatment suggesting shorter duration of response on CDKI + HT, which is markedly inferior to reported data for non-IBC patients from phase III trials. Show less

Developing highly potent covalent inhibitors of Fibroblast growth factor receptors 1 (FGFR1) has always been a challenging task. In the current study, various computational techniques, such as 3D-QSAR, covalent docking, fingerprinting analysis, MD simulation followed by MMGB/PBSA, and per-residue energy decomposition analysis were used to explore the binding mechanism of pyrazolo[3,4-d]pyridazinone derivatives to FGFR1. The high q2 and r2 values for the CoMFA and CoMSIA models, suggest that the constructed 3D-QSAR models could reliably predict the bioactivities of FGFR1 inhibitors. The structural requirements revealed by the model's contour maps were strategically used to computationally create an in-house library of more than 100 new FGFR1 inhibitors using the R-group exploration technique implemented in the Spark Show less

Phthalates are widely used synthetic chemicals that determine endocrine disruption effects on female reproductivity and oviposition. Our study demonstrated that the mitochondrial quality in ovarian granulosa cells (GCs) is associated with a poor prognosis in female reproduction. However, the molecular mechanism of di-(2-ethylhexyl) phthalate (DEHP) exposure on the quail ovarian GC layer is still unknown. To validate the effects of DEHP on the GC layer, 8 days' old 150 female Japanese quail were treated orally with DEHP (250, 500, and 750 mg/kg BW/day) for 45 days to explore the toxic effects of DEHP on the ovarian GC layer. Histopathological assessment and ultrastructure observation found that DEHP decreased the thickness of the GC layer, resulted in mitochondrial damage, and activated mitocytosis. Additionally, the results further suggested that DEHP impacted the secretion of steroid hormones (reduced FSH, E2, and T levels and boosted Prog, PRL, and LH levels) by triggering mitocytosis (enhanced transcription of Show less

Genome-wide association studies (GWASs) have implicated ∼380 genetic loci for plasma lipid regulation. However, these loci only explain 17-27% of the trait variance, and a comprehensive understanding of the molecular mechanisms has not been achieved. In this study, we utilized an integrative genomics approach leveraging diverse genomic data from human populations to investigate whether genetic variants associated with various plasma lipid traits, namely, total cholesterol, high and low density lipoprotein cholesterol (HDL and LDL), and triglycerides, from GWASs were concentrated on specific parts of tissue-specific gene regulatory networks. In addition to the expected lipid metabolism pathways, gene subnetworks involved in "interferon signaling," "autoimmune/immune activation," "visual transduction," and "protein catabolism" were significantly associated with all lipid traits. In addition, we detected trait-specific subnetworks, including cadherin-associated subnetworks for LDL; glutathione metabolism for HDL; valine, leucine, and isoleucine biosynthesis for total cholesterol; and insulin signaling and complement pathways for triglyceride. Finally, by using gene-gene relations revealed by tissue-specific gene regulatory networks, we detected both known (e.g., APOH, APOA4, and ABCA1) and novel (e.g., F2 in adipose tissue) key regulator genes in these lipid-associated subnetworks. Knockdown of the F2 gene (coagulation factor II, thrombin) in 3T3-L1 and C3H10T1/2 adipocytes altered gene expression of Abcb11, Apoa5, Apof, Fabp1, Lipc, and Cd36; reduced intracellular adipocyte lipid content; and increased extracellular lipid content, supporting a link between adipose thrombin and lipid regulation. Our results shed light on the complex mechanisms underlying lipid metabolism and highlight potential novel targets for lipid regulation and lipid-associated diseases. Show less

Neurodegenerative diseases characterized by aberrant accumulation of undigested cellular components represent unmet medical conditions for which the identification of actionable targets is urgently needed. Here we identify a pharmacologically actionable pathway that controls cellular clearance via Akt modulation of transcription factor EB (TFEB), a master regulator of lysosomal pathways. We show that Akt phosphorylates TFEB at Ser467 and represses TFEB nuclear translocation independently of mechanistic target of rapamycin complex 1 (mTORC1), a known TFEB inhibitor. The autophagy enhancer trehalose activates TFEB by diminishing Akt activity. Administration of trehalose to a mouse model of Batten disease, a prototypical neurodegenerative disease presenting with intralysosomal storage, enhances clearance of proteolipid aggregates, reduces neuropathology and prolongs survival of diseased mice. Pharmacological inhibition of Akt promotes cellular clearance in cells from patients with a variety of lysosomal diseases, thus suggesting broad applicability of this approach. These findings open new perspectives for the clinical translation of TFEB-mediated enhancement of cellular clearance in neurodegenerative storage diseases. Show less

Evidence is sparse about the genetic determinants of major lipids in Pakistanis. Variants (n=45 000) across 2000 genes were assessed in 3200 Pakistanis and compared with 2450 Germans using the same gene array and similar lipid assays. We also did a meta-analysis of selected lipid-related variants in Europeans. Pakistani genetic architecture was distinct from that of several ethnic groups represented in international reference samples. Forty-one variants at 14 loci were significantly associated with levels of HDL-C, triglyceride, or LDL-C. The most significant lipid-related variants identified among Pakistanis corresponded to genes previously shown to be relevant to Europeans, such as CETP associated with HDL-C levels (rs711752; P<10(-13)), APOA5/ZNF259 (rs651821; P<10(-13)) and GCKR (rs1260326; P<10(-13)) with triglyceride levels; and CELSR2 variants with LDL-C levels (rs646776; P<10(-9)). For Pakistanis, these 41 variants explained 6.2%, 7.1%, and 0.9% of the variation in HDL-C, triglyceride, and LDL-C, respectively. Compared with Europeans, the allele frequency of rs662799 in APOA5 among Pakistanis was higher and its impact on triglyceride concentration was greater (P-value for difference <10(-4)). Several lipid-related genetic variants are common to Pakistanis and Europeans, though they explain only a modest proportion of population variation in lipid concentration. Allelic frequencies and effect sizes of lipid-related variants can differ between Pakistanis and Europeans. Show less

Asymmetric delivery and distribution of macromolecules are essential for cell polarity and for cellular functions such as differentiation, division, and signaling. Injury of podocytes, which are polarized epithelial cells, changes the dynamics of the actin meshwork, resulting in foot process retraction and proteinuria. Although the spatiotemporal control of specific protein-protein interactions is crucial for the establishment of cell polarity, the mechanisms controlling polarity-dependent differentiation and division are incompletely understood. In this study, yeast two-hybrid screens were performed using a podocyte cDNA library and the polarity protein PATJ as bait. The protein KIBRA was identified as an interaction partner of PATJ and was localized to podocytes, tubular structures, and collecting ducts. The last four amino acids of KIBRA mediated binding to the eighth PDZ domain of PATJ. In addition, KIBRA directly bound to synaptopodin, an essential organizer of the podocyte cytoskeleton. Stable knockdown of KIBRA in immortalized podocytes impaired directed cell migration, suggesting that KIBRA modulates the motility of podocytes by linking polarity proteins and cytoskeleton-associated protein complexes. Show less