High frequency of mutations of the PIK3CA gene in human cancers

Discovery of a selective PI3Kα inhibitor via structure-based virtual screening for targeted colorectal cancer therapy

Colorectal cancer (CRC) remains a leading cause of cancer-related mortality globally, driving an urgent need for effective therapies. A promising avenue of research focuses on the PI3K/AKT/mTOR signalling pathway, which is frequently disrupted by mutations in the PI3Kα subunit. Our cutting-edge study employed a structure-based virtual screening of ∼3000 compounds, leading to the discovery of F0608-0019, a highly potent and selective PI3Kα inhibitor. F0608-0019 demonstrated remarkable efficacy in suppressing HCT116 colorectal cancer cell proliferation, with an IC50 of 12.14 µM, while maintaining high selectivity by minimising activity against other PI3K isoforms. Advanced molecular dynamics simulations highlighted the stability of F0608-0019's binding interactions with key amino acids, such as TRP:780, ILE:932, and VAL:850, which are critical for its targeted action. These exciting findings reveal F0608-0019 as a leading candidate for innovative CRC therapies that selectively target PI3Kα dysregulation, offering promising new possibilities for effective CRC treatment.

Unravelling key signaling pathways for the therapeutic targeting of non-small cell lung cancer

Lung cancer (LC) remains the foremost cause of cancer-related mortality across the globe. Non-small cell lung cancer (NSCLC) is a type of LC that exhibits significant heterogeneity at histological and molecular levels. Genetic alterations in upstream signaling molecules activate cascades affecting apoptosis, proliferation, and differentiation. Disruption of these signaling pathways leads to the proliferation of cancer-promoting cells, progression of cancer, and resistance to its treatment. Recent insights into the function of signaling pathways and their fundamental mechanisms in the onset of various diseases could pave the way for new therapeutic approaches. Recently, numerous drug molecules have been created that target these cell signaling pathways and could be used alongside other standard therapies to achieve synergistic effects in mitigating the pathophysiology of NSCLC. Additionally, many researchers have identified several predictive biomarkers, and alterations in transcription factors and related pathways are employed to create new therapeutic strategies for NSCLC. Findings suggest using specific inhibitors to target cellular signaling pathways in tumor progression to treat NSCLC. This review investigates the role of signaling pathways in NSCLC development and explores novel therapeutic strategies to enhance clinical treatment options for NSCLC.

Targeting PI3K in cancer treatment: A comprehensive review with insights from clinical outcomes

The phosphoinositide 3-kinase (PI3K) pathway plays a crucial role in cancer, including cell growth, survival, metabolism, and metastasis. Its major role in tumor growth makes it a key target for cancer therapeutics, offering significant potential to slow tumor progression and enhance patient outcomes. Gain-of-function mutations, gene amplifications, and the loss of regulatory proteins like PTEN are frequently observed in malignancies, contributing to tumor development and resistance to conventional treatments such as chemotherapy and hormone therapy. As a result, PI3K inhibitors have received a lot of interest in cancer research. Several kinds of small-molecule PI3K inhibitors have been developed, including pan-PI3K inhibitors, isoform-specific inhibitors, and dual PI3K/mTOR inhibitors, each targeting a distinct component of the pathway. Some PI3K inhibitors such as idelalisib, copanlisib, duvelisib, alpelisib, and umbralisib have received FDA-approval, and are effective in the treatment of breast cancer and hematologic malignancies. Despite promising results in preclinical and clinical trials, the overall clinical success of PI3K inhibitors has been mixed. While some patients may get substantial advantages, a considerable number of them acquire resistance as a result of feedback activation of alternative pathways, adaptive tumor responses, and treatment-emergent mutations. The resistance mechanisms provide barriers to the sustained efficacy of PI3K-targeted treatments. This study reviews recent advancements in PI3K inhibitors, covering their clinical status, mechanism of action, resistance mechanisms, and strategies to overcome resistance.

Study of immunosenescence in the occurrence and immunotherapy of gastrointestinal malignancies

In human beings heterogenous, pervasive and lethal malignancies of different parts of the gastrointestinal (GI) tract viz., tumours of the oesophagus, stomach, small intestine, colon, and rectum, represent gastrointestinal malignancies. Primary treatment modality for gastric cancer includes chemotherapy, surgical interventions, radiotherapy, monoclonal antibodies and inhibitors of angiogenesis. However, there is a need to improve upon the existing treatment modality due to associated adverse events and the development of resistance towards treatment. Additionally, age has been found to contribute to increasing the incidence of tumours due to immunosenescence-associated immunosuppression. Immunosenescence is the natural process of ageing, wherein immune cells as well as organs begin to deteriorate resulting in a dysfunctional or malfunctioning immune system. Accretion of senescent cells in immunosenescence results in the creation of a persistent inflammatory environment or inflammaging, marked with elevated expression of pro-inflammatory and immunosuppressive cytokines and chemokines. Perturbation in the T-cell pools and persistent stimulation by the antigens facilitate premature senility of the immune cells, and senile immune cells exacerbate inflammaging conditions and the inefficiency of the immune system to identify the tumour antigen. Collectively, these conditions contribute positively towards tumour generation, growth and eventually proliferation. Thus, activating the immune cells to distinguish the tumour cells from normal cells and invade them seems to be a logical strategy for the treatment of cancer. Consequently, various approaches to immunotherapy, viz., programmed death ligand-1 (PD-1) inhibitors, Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) inhibitors etc are being extensively evaluated for their efficiency in gastric cancer. In fact, PD-1 inhibitors have been sanctioned as late late-line therapy modality for gastric cancer. The present review will focus on deciphering the link between the immune system and gastric cancer, and the alterations in the immune system that incur during the development of gastrointestinal malignancies. Also, the mechanism of evasion by tumour cells and immune checkpoints involved along with different approaches of immunotherapy being evaluated in different clinical trials will be discussed.

Switching from messenger RNAs to noncoding RNAs, METTL3 is a novel colorectal cancer diagnosis and treatment target

N6-methyladenosine (m6A) modification, one of the most prevalent RNA epigenetic modifications in eukaryotes, constitutes over 60% of all RNA methylation modifications. This dynamic modification regulates RNA processing, maturation, nucleocytoplasmic transport, translation efficiency, phase separation, and stability, thereby linking its dysregulation to diverse physiological and pathological processes. METTL3, a core catalytic component of the methyltransferase complex responsible for m6A deposition, is frequently dysregulated in diseases, including colorectal cancer (CRC). Although METTL3’s involvement in CRC pathogenesis has been documented, its precise molecular mechanisms and functional roles remain incompletely understood. METTL3 mediates CRC progression-encompassing proliferation, invasion, drug resistance, and metabolic reprogramming-through m6A-dependent modulation of both coding RNAs and noncoding RNAs. Its regulatory effects are primarily attributed to interactions with key signaling pathways at multiple stages of CRC development. Emerging evidence highlights METTL3 as a promising biomarker for CRC diagnosis and prognosis, as well as a potential therapeutic target. By synthesizing recent advances in METTL3 research within CRC, this review provides critical insights into novel strategies for clinical diagnosis and targeted therapy.

Therapeutic efficacy of TMTP1-modified EVs in overcoming bone metastasis and immune resistance in PIK3CA mutant NSCLC

Non-small cell lung cancer (NSCLC) with PIK3CA mutations demonstrates significant challenges in treatment due to enhanced bone metastasis and immune checkpoint resistance. This study investigates the efficacy of tumor-targeting peptide 1-modified cancer stem cell-derived extracellular vesicles (TMTP1-TSRP-EVs) in reshaping the tumor microenvironment and reversing immune checkpoint resistance in NSCLC. By integrating TMTP1-TSRP into EVs, we aim to specifically deliver therapeutic agents to NSCLC cells, focusing on inhibiting the PI3K/Akt/mTOR pathway, a crucial driver of oncogenic activity and immune evasion in PIK3CA-mutated cells. Our comprehensive in vitro and in vivo analyses show that TMTP1-TSRP-EVs significantly inhibit tumor growth, reduce PD-L1 expression, and enhance CD8+ T cell infiltration, effectively reversing the immune-suppressive microenvironment. Moreover, the in vivo models confirm that our approach not only suppresses bone metastases but also overcomes primary resistance to immune checkpoint inhibitors by modulating the expression of key immunological markers. These findings suggest that targeted delivery of TMTP1-TSRP-EVs could provide a novel therapeutic strategy for treating PIK3CA-mutant NSCLC, offering significant improvements over traditional therapies by directly targeting the molecular pathogenesis of tumor resistance and metastasis. Molecular Mechanisms Reshaping the TME to Halt PI3K-Mutant Bone Metastasis of NSCLC and Overcoming Primary ICI Resistance. (Created by BioRender).

Oncogenic Signalling Pathways in Cancer Immunotherapy: Leader or Follower in This Delicate Dance?

Immune checkpoint inhibitors have become a mainstay of treatment in many solid organ malignancies. Alongside this has been the rapid development in the identification and targeting of oncogenic drivers. The presence of alterations in oncogenic drivers not only predicts response to target therapy but can modulate the immune microenvironment and influence response to immunotherapy. Combining immune checkpoint inhibitors with targeted agents is an attractive therapeutic option but overlapping toxicity profiles may limit the clinical use of some combinations. In addition, there is growing evidence of shared resistance mechanisms that alter the response to immunotherapy when it is used after targeted therapy. Understanding this complex interaction between oncogenic drivers, targeted therapy and response to immune checkpoint inhibitors is vital for selecting the right treatment, at the right time for the right patient. In this review, we summarise the preclinical and clinical evidence of the influence of four common oncogenic alterations on immune checkpoint inhibitor response, combination therapies, and the presence of shared resistance mechanisms. We highlight the common resistance mechanisms and the need for more randomised trials investigating both combination and sequential therapy.

Role of the Wnt signaling pathway in the complex microenvironment of breast cancer and prospects for therapeutic potential (Review)

The focus on breast cancer treatment has shifted from the cytotoxic effects of single drugs on tumor cells to multidimensional multi‑pathway synergistic intervention strategies targeting the tumor microenvironment (TME). The activation of the Wnt signaling pathway in the TME of breast cancer cells serves a key regulatory role in tissue homeostasis and is a key driver of the carcinogenic process. Modulating the crosstalk between the Wnt pathway and TME of breast cancer is key for understanding the biological behavior of breast cancer and advancing the development of novel antitumor drugs. The present review aimed to summarize the complex mechanisms of the Wnt signaling pathway in the breast cancer TME, interactions between the Wnt signaling pathway and components of the breast cancer TME and breast cancer‑associated genes, as well as the interactions between the Wnt signaling pathway and other signaling cascades at the molecular level. Furthermore, the present review aimed to highlight the unique advantages of the Wnt signaling pathway in the macro‑regulation of the TME and the current therapeutic strategies targeting the Wnt signaling pathway, their potential clinical value and future research directions in breast cancer treatment.

C15orf39, a downstream effector of PI3K/AKT signaling, promotes gastric carcinogenesis and correlates with patient outcomes

The phosphatidylinositol-3-kinases (PI3K) signaling pathway is highly complex and well-known to exert oncogenic roles in multiple cancer types. Exploring new factors involved in this pathway may offer the potential for improving the early diagnosis and treatment strategies for cancers. Here we used gastric cancer (GC) as a model to identify co-regulated effectors downstream of three catalytic subunits of PI3K through high-throughput sequencing in PIK3CA, PIK3CB, and PIK3CD knockdown GC cells. C15orf39, a new uncharacterized gene, was selected due to the most significant expression change. qRT-PCR and immunohistochemistry analyses revealed that C15orf39 was frequently upregulated in GC tissues and strongly correlated with poor clinical outcomes in GC patients. Gain- and loss-of-function studies demonstrated that C15orf39 promoted GC cell proliferation, migration, and drug resistance. Mechanistically, C15orf39 promoted GC progression possibly via modulating cell mitosis and cell cycle. FOXK2, a transcription factor activated by PI3K/AKT signaling, could bind to the promoter of C15orf39 and positively regulate C15orf39 expression. These findings unveiled a new PI3K/AKT/FOXK2/C15orf39 signaling axis that promotes GC development and progression. C15orf39 may become a potential biomarker for early diagnosis and personalized treatment to improve the prognosis of GC patients.

CDK4/6 inhibition in early and advanced hormone receptor-positive, HER2-negative breast cancer

INTRODUCTION

Cyclin-dependent kinase 4 and 6 (CDK4/6) inhibition in combination with endocrine therapy is the mainstay of treatment for hormone receptor-positive, HER2-negative (HR  +  /HER2-) advanced breast cancer; the CDK4/6 inhibitors abemaciclib and ribociclib are also approved for high-risk, early-stage, HR  +  /HER2- breast cancer. Numerous studies exploring CDK4/6 inhibitors in the early-stage setting are ongoing, as well as many more exploring novel combinations in the metastatic setting.

AREAS COVERED

Here, we review the basis of CDK4/6 inhibition for HR  +/HER2- breast cancer, the pivotal clinical trials which led to regulatory approval, and ongoing trials evaluating novel combinations to further improve outcomes for those with both early and advanced HR+/HER2- breast cancer. Current literature was reviewed by a comprehensive search of PubMed MEDLINE (1/1/2000-12/31/2024).

EXPERT OPINION

CDK4/6 inhibitors are integral in the management of both advanced and high-risk, early-stage HR  +  /HER2- breast cancer. Biomarkers predictive of CDK 4/6 inhibitor (CDK4/6i) benefit remain elusive, and clinical and pathological features remain key to identifying those who are candidates for CDK4/6 inhibition in the early-stage setting. Numerous trials evaluating the role of a CDK4/6i with novel endocrine therapy partners and other targeted agents are ongoing, with the goal of improving outcomes for those with HR  +  /HER2- disease.

The genetic architecture of bone metastases: unveiling the role of epigenetic and genetic modifications in drug resistance

Bone metastases represent frequent and severe complications in various cancers, notably impacting prognosis and quality of life. This review article delves into the genetic and epigenetic mechanisms underpinning drug resistance in bone metastases, a key challenge in effective cancer treatment. The development of drug resistance in cancer can manifest as either intrinsic or acquired, with genetic heterogeneity playing a pivotal role. Intrinsic resistance is often due to pre-existing mutations, while acquired resistance evolves through genetic and epigenetic alterations during treatment. These alterations include mutations in driver genes like TP53 and RB1, epigenetic modifications such as DNA methylation and histone changes, and pathway alterations, notably involving RANK-RANKL signaling and the PI3K/AKT/mTOR cascade. Recent studies underline the significance of the tumor microenvironment in fostering drug resistance, with components such as cancer-associated fibroblasts and hypoxia playing crucial roles. The interactions between metastatic cancer cells and the bone microenvironment facilitate survival and the proliferation of drug-resistant clones. This review highlights the necessity of understanding these complex interactions to develop targeted therapies that can overcome resistance and improve treatment outcomes. Current therapeutic strategies and future directions are discussed, emphasizing the integration of genomic profiling and targeted interventions in managing bone metastases. The evolving landscape of genetic research, including the application of next-generation sequencing and CRISPR technology, offers promising avenues for novel and more effective therapeutic strategies. This comprehensive exploration aims to provide insights into the molecular intricacies of drug resistance in bone metastases, paving the way for improved clinical management and patient care.

Targeting the phosphatidylinositol-3-kinase (PI3K) and mitogen activated protein kinase (MAPK) signalling pathways to enhance chemoradiotherapy in locally advanced rectal cancer

Responses to neoadjuvant chemoradiotherapy for locally advanced rectal cancer are not uniform. The phosphatidylinositol-3 kinase (PI3K) and mitogen-activated protein kinase (MAPK) pathways are involved in tumorigenesis and treatment resistance in many cancers; therefore, targeting these pathways could enhance response to chemoradiotherapy. A panel of colorectal cancer (CRC) cell lines (n = 10) with varying PI3K and MAPK mutational backgrounds were treated with combinations of 5-Flourouracil (5-FU), radiation, the PI3K inhibitor copanlisib, and/or the MEK inhibitor refametinib, and their effects on proliferation in vitro were measured. BALB/c SCID mice were implanted with CRC cell lines representative of each mutational background, treated with copanlisib and/or chemoradiotherapy, and monitored for tumor growth. In vitro, PIK3CA mutated cell lines were most sensitive to copanlisib (IC50=28 nM) and KRAS mutated cell lines were most sensitive to refametinib (IC50 = 36 nM), while the combination of copanlisib and refametinib was synergistic in 9/10 cell lines tested. The addition of copanlisib to 5-FU chemoradiotherapy inhibited cell growth compared to 5-FU chemoradiotherapy alone, an effect that was most notable in LS-1034 (KRAS mutated) and Caco-2 (PIK3CA/KRAS wild-type) cell lines. In vivo copanlisib and 5-FU chemoradiotherapy reduced tumor growth in all xenograft models and increased overall survival in LS-1034 and Caco-2 xenografts. Our results suggest that activation of the kinase signalling pathway may modulate PI3K/MEK inhibitor responsiveness in colorectal cancer. Furthermore, the addition of copanlisib to 5-FU chemoradiotherapy resulted in an enhanced anti-proliferative cytotoxic effect compared to 5-FU chemoradiotherapy alone, regardless of the background mutational status, and supports further clinical development of this regimen.

Advances in cancer genomics and precision oncology

BACKGROUND

Next-generation sequencing has revolutionized genome science over the last two decades. Indeed, the wealth of sequence information on our genome has deepened our understanding on cancer. Cancer is a genetic disease caused by genetic or epigenetic alternations that affect the expression of genes that control cell functions, particularly cell growth and division. Utilization of next-generation sequencing in cancer gene panels has enabled the identification of actionable gene alterations in cancer patients to guide personalized precision medicine.

OBJECTIVE

The aim is to provide information that can identify actionable gene alterations, enabling personalized precision medicine for cancer patients.

RESULTS & DISCUSSION

Equipped with next-generation sequencing techniques, international collaboration programs on cancer genomics have identified numerous mutations, gene fusions, microsatellite variations, copy number variations, and epigenetics changes that promote the transformation of normal cells into tumors. Cancer classification has traditionally been based on cell type or tissue-of-origin and the morphological characteristics of the cancer. However, interactive genomic analyses have currently reclassified cancers based on systemic molecular-based taxonomy. Although all cancer-causing genes and mechanisms have yet to be completely understood or identified, personalized or precision medicine is now currently possible for some forms of cancer. Unlike the "one-size-fits-all" approach of traditional medicine, precision medicine allows for customized or personalized treatment based on genomic information.

CONCLUSION

Despite the availability of numerous cancer gene panels, technological innovation in genomics and expansion of knowledge on the cancer genome will allow precision oncology to manage even more types of cancers.

Combinatorial screen of targeted agents with the PI3K inhibitors inavolisib, alpelisib, duvelisib, and copanlisib in multi-cell type tumor spheroids

Dysregulation of the phosphatidylinositol 3-kinase (PI3K) pathway is a key contributor to cancer, making PI3K inhibitors a promising approach for targeted therapy. The selectivity of available inhibitors varies across different PI3K isoforms. Alpelisib and inavolisib are selective for the α-isoform, while duvelisib targets the δ- and γ-isoforms, and copanlisib is a pan-PI3K inhibitor, active against all isoforms. This study investigated the activity of these four PI3K inhibitors in combination with other targeted agents using multi-cell type tumor spheroids composed of 60% malignant cells, 25% endothelial cells, and 15% mesenchymal stem cells. Twenty-nine tumor spheroid models were evaluated, including twenty-six patient-derived cancer cell lines from the NCI Patient-Derived Models Repository and three established cell lines from the NCI-60 human tumor cell line panel. Additive and/or synergistic effects were observed with alpelisib or inavolisib or copanlisib in combination with a RAS/MEK/ERK pathway inhibitor, either selumetinib (MEK), ravoxertinib (ERK 1/2), or tovorafenib (DAY101, RAF). Combinations of each of these three PI3K inhibitors with the KRAS mutation specific inhibitors MTRX1133 (KRAS G12D) or sotorasib (KRAS G12C) had selective activity in cell lines harboring the corresponding target. Lastly, combination effects were observed from vertical inhibition of the PI3K/AKT/mTOR pathway with a PI3K inhibitor in combination with either the mTORC1/2 inhibitor sapanisertib or an AKT inhibitor, ipatasertib or afuresertib.

Vertical inhibition of p110α/AKT and N-cadherin enhances treatment efficacy in PIK3CA-aberrated ovarian cancer cells

Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha [PIK3CA, encoding PI3Kalpha (also known as p110α)] is one of the most commonly aberrated genes in human cancers. In serous ovarian cancer, PIK3CA amplification is highly frequent but PIK3CA point mutation is rare. However, whether PIK3CA amplification and PIK3CA driver mutations have the same functional impact in the disease is unclear. Here, we report that both PIK3CA amplification and E545K mutation are tumorigenic. While the protein kinase B (AKT) signaling axis was activated in both E545K knock-in cells and PIK3CA-overexpressing cells, the mitogen-activated protein kinase 3/1 (ERK1/2) pathway was induced selectively by E545K mutation but not PIK3CA amplification. Intriguingly, AKT signaling in these PIK3CA-aberrated cells increased transcriptional coactivator YAP1 (YAP) Ser127 phosphorylation and thereby cytoplasmic YAP levels, which in turn increased cell migration through Ras-related C3 botulinum toxin substrate 1 (RAC1) activation. In addition to the altered YAP signaling, AKT upregulated N-cadherin expression, which also contributed to cell migration. Pharmacological inhibition of N-cadherin reduced cell migratory potential. Importantly, co-targeting N-cadherin and p110α/AKT caused additive reduction in cell migration in vitro and metastases formation in vivo. Together, this study reveals the molecular pathways driven by the PIK3CA aberrations and the exploitable vulnerabilities in PIK3CA-aberrated serous ovarian cancer cells.

Molecular substratification of endometrial carcinomas with no special molecular profile (NSMP) by using a limited NGS custom panel may facilitate effective patient selection for the PIK3CA-targeted therapy

Endometrial carcinomas (EC) of no special molecular profile (NSMP) represent the largest molecular category of EC, comprising a mixture of tumors with different histology and molecular profiles. These facts likely point to different tumor biology, clinical outcomes, and targeted therapy responses within this molecular category. The PIK3CA is currently the only targetable kinase oncoprotein directly implicated in EC carcinogenesis. Investigating a unique single-institution cohort, we attempted to stratify NSMP ECs based on the presence of the PIK3CA pathogenic mutation. Those cases were further analyzed for other well-established-associated oncogenic driver gene mutations. Histological and clinical variables were also correlated in each case. Altogether, 175 ECs were prospectively tested by a limited custom NGS panel containing ARID1A, BCOR, BRCA1, BRCA2, CTNNB1, KRAS, MLH1, MSH2, MSH6, NRAS, PIK3CA, PMS2, POLD1, POLE, PTEN,and TP53 genes. We identified 24 PIK3CA mutated cases in the group of 80 NSMP ECs, with another co-occurring mutation in at least one oncogenic driver gene (CTNNB1, PTEN, ARID1A, KRAS, BCOR, PMS2) in 19 cases. In conclusion, a limited NGS panel can effectively test EC tissue for specific pathogenetically relevant oncogene mutations. The NSMP EC category contains 30% of the PIK3CA mutated cases. Of those, 21% contain the PIK3CA mutation as a sole EC-associated oncogene mutation, while 79% harbor at least one more mutated gene. These findings may inform future healthcare planning and improve the effectiveness of EC patient selection for the PIK3CA-targeted therapy.

Overexpression of PIK3CG in Cancer Cells Promotes Lung Cancer Cell Migration and Metastasis Through Enhanced MMPs Expression and Neutrophil Recruitment and Activation

Metastasis is a major cause of death in lung cancer. The aim of this study is to analyze the role and mechanism of PI3K catalytic subunit gamma (PIK3CG, also known as p110γ) in lung cancer cell migration and metastasis. Knockdown (KD) and overexpression (OE) of PIK3CG expression in lung cancer cell lines A549 and H1299 in vitro cultured was achieved. Two PIK3CG-specific inhibitors, Eganelisib and CAY10505, were used to treat A549 and H1299 cells. An experimental lung metastasis mouse model was constructed using tail vein injection of LLC cells. Finally, a co-culture system was established using Transwell chambers. Compared with the NC group, the number of cells that completed migration and the expression levels of matrix metalloproteinases (MMPs) were significantly reduced in the KD group and Eganelisib and CAY10505 treatment groups, while the number of cells that migrated successfully and the expression levels of MMPs were significantly increased in the OE group. Lung tissues of mice injected with PIK3CG-stabilized overexpressed LLC cells showed more pronounced lung cancer growth, lung metastatic nodules, neutrophil infiltration and MMPs expression. Co-culture with neutrophils, soluble extracts of neutrophils and cathepsin G all promoted the migration of lung cancer cells. PIK3CG overexpression in tumor cells significantly promoted the migration and metastasis of lung cancer cell.

Targeting NUCKS1 with a fragment of tRNAAsn(GUU) of Chinese yew for the treatment of colorectal cancer

Despite the discovery of numerous oncogenes in colorectal cancer (CRC), the development of associated drugs is limited, posing a significant challenge for CRC treatment. Identification of novel druggable targets is therefore crucial for the therapeutic development of CRC. Here, we report the first investigation on therapeutics targeting the potent oncogene NUCKS1 to suppress cancer progression. NUCKS1-orientated bioinformatics screening of NUCKS1 inhibitors from our library of tRNA fragments originated from medicinal plants identified tRF-T36, a 5' tRNA fragment of tRNAAsn(GUU) of Chinese yew (Taxus chinensis), exhibiting stronger inhibitory effects than taxol against CRC progression. Mechanistically, tRF-T36 binds directly to the 3' UTR of NUCKS1 mRNA to downregulate its expressions via RNAi pathway. High-throughput RNA sequencing indicated that the downregulated NUCKS1 induced by tRF-T36 further inhibits PI3K/Akt pathway, as verified by the significantly efficacy decrease of tRF-T36 mimic in co-treatment with 740Y-P, an agonist of PI3K/Akt pathway. Collectively, our findings emphasize the importance of NUCKS1 as a promising druggable target for CRC. Furthermore, the present study provides the first siRNA sequence, tRF-T36 mimic, as small RNA drug candidate, thereby shedding light on CRC therapeutics.

Hybrid granular cell tumor/perineurioma: a report of two rare cases with PIK3CA mutations

Hybrid peripheral nerve sheath tumors (PNSTs) are rare mesenchymal neoplasms with dual differentiation, most often combining two of the three main PNST types: schwannoma, neurofibroma, and perineurioma. Recognized by the WHO since 2013, these tumors can also exhibit fewer common combinations, such as hybrid granular cell tumor/perineurioma. We herein report two rare cases of hybrid granular cell tumor perineurioma with molecular analysis. Both tumors presented as dermal to subcutaneous, well-circumscribed lesions composed of a combination of spindled and granular cell components. By immunohistochemistry, the granular cells were positive for S100, SOX10, and CD68, while the perineurial cells were highlighted by EMA and GLUT1 stains. Subsequent molecular testing revealed pathogenic mutations involving PIK3CA in both cases. Our study expands on the clinical and pathologic spectrum and provides the first molecular data on these unusual neoplasms. Further, we provide a comprehensive review of the literature of all previously reported cases and briefly discuss relevant differential diagnoses and their molecular features.

Effects of AKT Inhibitors for PIK3CA/AKT1/PTEN-Altered Advanced or Metastatic Breast Cancer: A Meta-Analysis of Randomized Clinical Trials

PURPOSE

We aimed to answer the following question: How effective is the addition of AKT inhibitors to the treatment of advanced or metastatic breast cancer?

METHODS

We searched PubMed, Embase and Cochrane for randomized controlled trials (RCTs) that investigated AKT inhibitors for advanced or metastatic BC. We computed hazard-ratios (HRs) for binary endpoints.

RESULTS

A total of 5 RCTs were included in the meta-analysis, comprising 1,334 patients with BC. The use of AKT inhibitors demonstrated a significant improvement in OS (HR 0.70; 95% CI, 0.58-0.85; P < .001) and PFS (HR 0.6797; 95% CI, 0.5499-0.8403; P < .001) in the overall population. Within the PIK3CA/AKT1/PTEN-altered subgroup (n = 645), the OS rate also significantly favored AKT inhibitors over the control group (HR 0.62; 95% CI, 0.42-0.92; P = .019), as well as PFS (HR 0.5224; 95% CI, 0.3366-0.8105; P = .004).

CONCLUSIONS

Our findings suggest that the incorporation of AKT inhibitors holds promise for treating patients with advanced or metastatic PIK3CA/AKT1/PTEN-altered BC.

Nanomedicine innovations in colon and rectal cancer: advances in targeted drug and gene delivery systems

Nanotechnology has revolutionized cancer diagnostics and therapy, offering unprecedented possibilities to overcome the constraints of conventional treatments. This study provides a detailed overview of the current progress and difficulties in the creation of nanostructured materials, with a specific emphasis on their use in drug and gene delivery systems. The study examines tactics that attempt to improve the effectiveness and safety of chemotherapeutic drugs such as doxorubicin (Dox) by focusing on the potential of antibody-drug conjugates and functionalized nanoparticles. Moreover, it clarifies the challenges encountered in administering nanoparticles orally for gastrointestinal treatments, emphasizing the crucial physicochemical properties that affect their behavior in the gastrointestinal system. This study highlights the transformational potential of nanostructured materials in precision oncology by examining advanced breakthroughs such cell membrane-camouflaged nanoparticles and inorganic nanoparticles designed for gastrointestinal disorders. The text investigates the processes involved in the absorption of nanoparticles and their destruction in lysosomes, revealing the many methods in which enterocytes take up these particles. This study strongly supports the use of advanced nanoparticle-based methods to reduce the harmful effects on the whole body and improve the effectiveness of therapy, based on a thorough examination of current experiments on animals and humans. The main objective of this paper is to provide a fundamental comprehension that will stimulate more investigation and practical use in the field of cancer nanomedicine, advancing its boundaries.

Decoding the functional impact of the cancer genome through protein-protein interactions

Acquisition of genomic mutations enables cancer cells to gain fitness advantages under selective pressure and, ultimately, leads to oncogenic transformation. Interestingly, driver mutations, even within the same gene, can yield distinct phenotypes and clinical outcomes, necessitating a mutation-focused approach. Conversely, cellular functions are governed by molecular machines and signalling networks that are mostly controlled by protein-protein interactions (PPIs). The functional impact of individual genomic alterations could be transmitted through regulated nodes and hubs of PPIs. Oncogenic mutations may lead to modified residues of proteins, enabling interactions with other proteins that the wild-type protein does not typically interact with, or preventing interactions with proteins that the wild-type protein usually interacts with. This can result in the rewiring of molecular signalling cascades and the acquisition of an oncogenic phenotype. Here, we review the altered PPIs driven by oncogenic mutations, discuss technologies for monitoring PPIs and provide a functional analysis of mutation-directed PPIs. These driver mutation-enabled PPIs and mutation-perturbed PPIs present a new paradigm for the development of tumour-specific therapeutics. The intersection of cancer variants and altered PPI interfaces represents a new frontier for understanding oncogenic rewiring and developing tumour-selective therapeutic strategies.

Oncogenic activation of PI K3 CA in cancers: Emerging targeted therapies in precision oncology

Phosphoinositide 3-kinases (PI3Ks) are heterodimers consisting of a p110 catalytic subunit and a p85 regulatory subunit. The PIK3CA gene, which encodes the p110α, is the most frequently mutated oncogene in cancer. Oncogenic PIK3CA mutations activate the PI3K pathway, promote tumor initiation and development, and mediate resistance to anti-tumor treatments, making the mutant p110α an excellent target for cancer therapy. PIK3CA mutations occur in two hotspot regions: one in the helical domain and the other in the kinase domain. The PIK3CA helical and kinase domain mutations exert their oncogenic function through distinct mechanisms. For example, helical domain mutations of p110α gained direct interaction with insulin receptor substrate 1 (IRS-1) to activate the downstream signaling pathways. Moreover, p85β proteins disassociate from helical domain mutant p110α, translocate into the nucleus, and stabilize enhancer of zeste homolog 1/2 (EZH1/2). Due to the fundamental role of PI3Kα in tumor initiation and development, PI3Kα-specific inhibitors, represented by FDA-approved alpelisib, have developed rapidly in recent decades. However, side effects, including on-target side effects such as hyperglycemia, restrict the maximum dose and thus clinical efficacy of alpelisib. Therefore, developing p110α mutant-specific inhibitors to circumvent on-target side effects becomes a new direction for targeting PIK3CA mutant cancers. In this review, we briefly introduce the function of the PI3K pathway and discuss how PIK3CA mutations rewire cell signaling, metabolism, and tumor microenvironment, as well as therapeutic strategies under development to treat patients with tumors harboring a PIK3CA mutation.

Challenges and prospects in HER2-positive breast cancer-targeted therapy

Breast cancer remains the most prevalent malignancy among women globally and ranks as the leading cause of cancer-related mortality in this demographic. Approximately 13 %-15 % of all breast cancer cases are classified as HER2-positive, a subtype associated with a particularly unfavorable prognosis. A large number of patients with HER2-positive breast cancer continue to face disease progression after receiving standardized treatment. Given these challenges, a thorough exploration into the mechanisms underlying drug resistance in HER2-targeted therapy is imperative. This review focuses on the factors related to drug resistance in HER2-targeted therapy, including tumor heterogeneity, antibody-binding efficacy, variations in the tumor microenvironment, and abnormalities in signal activation and transmission. Additionally, corresponding strategies to counteract these resistance mechanisms are discussed, to advance therapeutic efficacy and clinical benefits in the management of HER2-positive breast cancer.

The Combined Assessment of CTC and ESR1 Status in Liquid Biopsy Samples Enhances the Clinical Value of Prediction in Metastatic Breast Cancer

Monitoring of metastatic breast cancer (mBC) is an important issue in the clinical management of patients. Liquid biopsy has become a non-invasive method for detecting and monitoring cancer in body fluids. The presence of circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA) in peripheral blood indicates poor prognosis and may contribute to early detection of progression, but assessment of these levels is still not routine clinical management. The main objective of this study was to estimate the frequency and clinical value of the ESR1 and PIK3CA mutations identified in circulating free DNA (cfDNA.) The second goal was to evaluate whether simultaneous evaluation of CTCs and mutation status in cfDNA increases the prognostic value of liquid biopsy. The results of the analysis of the CTC number and ESR1 and PIK3CA mutations in blood collected from 179 patients with metastatic breast cancer show that ESR1 mutations are more frequent in patients with advanced luminal breast cancer regardless of the type of the treatment. ESR1 mutations appear primarily during progression, as no mutations were found in primary tumor samples. The main conclusion of the study is that combined assessment of CTCs and ESR1 status in liquid biopsy may improve the prognostic value of liquid biopsy.

Developments in research and commercialization of PI3K and AKT targets: a patent-based landscape

PI3K and AKT signaling pathway has been linked to the pathophysiology of various diseases. This pathway has emerged as a crucial therapeutic strategy for cancer and other diseases. To better understand recent development of PI3K and AKT, a patent-based landscape study was performed. The results shows that both PI3K and AKT targets have shown prolific patent filings over the past 20 years. This study is the first to depict the therapeutic applications of both PI3K and AKT targets based on a patent big data analysis. Ten key therapeutic applications were identified, with over 77% of patents related to anti-cancer therapy for both PI3K and AKT targets. Additionally, our findings show that combination therapy is a distinguishing feature for drugs targeting both PI3K and AKT. The average time from patent application to drug approval for PI3K target drugs is 8.8 years. PI3K target drugs obtain market approval faster compared to AKT drugs. Approximately, 2 years of patent term extension could be obtained if the time from the patent application date to the drug approval date is less than 10 years.

Understanding the conformational dynamics of PI3Kα due to helical domain mutations: insights from Markov state model analysis

Phosphoinositide 3-kinases (PI3Ks) phosphorylate phosphoinositides on the membrane, which act as secondary signals for various cellular processes. PI3Kα, a heterodimer of the p110α catalytic subunit and the p85α regulatory subunit, is activated by growth factor receptors or mutations. Among these mutations, E545K present in the helical domain is strongly associated with cancer, and is known to disrupt interactions between the regulatory and catalytic subunits, leading to its constitutive activation. However, while the mutation's role in disrupting autoinhibition is well documented, the molecular mechanisms linking this mutation in the helical domain to the structural changes in the kinase domain remain poorly understood. This study aims to understand the conformational events triggered by the E545K mutation, elucidate how these changes propagate from the helical domain to the kinase domain, and identify crucial residues involved in the activation process. Molecular dynamics (MD) simulations combined with Markov state modeling (MSM) were employed to explore the conformational landscapes of both the wild-type and mutant systems. Structural and energetic analyses, including Molecular Mechanics Poisson-Boltzmann Surface Area (MM-PBSA) calculations, revealed that the E545K mutation significantly reduces the binding affinity between the regulatory and catalytic subunits. The mutation was found to induce a sliding motion of the regulatory subunit along the catalytic subunit, leading to the disruption of key salt-bridges between these domains. This disruption releases the inhibitory effect of the regulatory subunit, resulting in increased domain motion, particularly in the adaptor-binding domain (ABD). Enhanced flexibility in the ABD, helical, and C2 domains facilitates the rearrangement of the two lobes of kinase domain, thereby promoting activation. Additionally, the mutation appears to enhance PI3Kα's membrane affinity via the Ras-binding domain (RBD). Network analysis helped to identify key residues that may involve in allosteric signaling pathways, providing insights into the communication between domains. Druggable pockets in the metastable states were predicted followed by its docking with a PI3K inhibitor library. Docking studies revealed the crucial residues that may be participating in inhibitor binding. The identification of residues and regions involved in activation mechanisms using MSM helped to reveal the conformational events and the knowledge on probable allosteric pockets, which may be helpful in designing better therapeutics.

The Influence of Phosphoinositide Lipids in the Molecular Biology of Membrane Proteins: Recent Insights from Simulations

The phosphoinositide family of membrane lipids play diverse and critical roles in eukaryotic molecular biology. Much of this biological activity derives from interactions of phosphoinositide lipids with integral and peripheral membrane proteins, leading to modulation of protein structure, function, and cellular distribution. Since the discovery of phosphoinositides in the 1940s, combined molecular biology, biophysical, and structural approaches have made enormous progress in untangling this vast and diverse cellular network of interactions. More recently, in silico approaches such as molecular dynamics simulations have proven to be an asset in prospectively identifying, characterising, explaining the structural basis of these interactions, and in the best cases providing atomic level testable hypotheses on how such interactions control the function of a given membrane protein. This review details a number of recent seminal discoveries in phosphoinositide biology, enabled by advanced biomolecular simulation, and its integration with molecular biology, biophysical, and structural biology approaches. The results of the simulation studies agree well with experimental work, and in a number of notable cases have arrived at the key conclusion several years in advance of the experimental structures. SUMMARY: Hedger and Yen review developments in simulations of phosphoinositides and membrane proteins.

Integrative analysis of m7G methylation-associated genes prognostic signature with immunotherapy and identification of LARP1 as a key oncogene in head and neck squamous cell carcinoma

Background

N7-methylguanosine (m7G) methylation is an RNA modification associated with cancer progression, but its specific role in head and neck squamous cell carcinoma (HNSCC) remains unclear.

Methods

This study analyzed the differential expression of m7G-related genes (m7GRGs) in HNSCC using the TCGA-HNSCC dataset, identifying key pathways associated with the cell cycle, DNA replication, and focal adhesion. A LASSO-Cox regression model was constructed based on four m7GRGs (EIF3D, EIF1, LARP1, and METTL1) and validated with GEO datasets and clinical samples. Further validation of gene upregulation in HNSCC tissues was conducted using RT-qPCR and immunohistochemistry, while the role of LARP1 in HNSCC cells was assessed via knockout experiments.

Results

The constructed model demonstrated strong predictive performance, with the risk score significantly correlating with prognosis, immune infiltration, and drug sensitivity. An external dataset and clinical specimens further confirmed the model's predictive accuracy for immunotherapy response. Additionally, two regulatory axes-LINC00707/hsa-miR-30b-5p/LARP1 and SNHG16/hsa-miR-30b-5p/LARP1-were identified. LARP1 knockout experiments revealed that suppressing LARP1 markedly inhibited HNSCC cell proliferation, migration, and invasion.

Conclusion

The m7GRG-based prognostic model developed in this study holds strong clinical potential for predicting prognosis and therapeutic responses in HNSCC. The identification of LARP1 and its related regulatory pathways offers new avenues for targeted therapy in HNSCC.

Genomic Alterations in Molecularly Defined Oligodendrogliomas

BACKGROUND AND OBJECTIVES

Oligodendrogliomas are defined by IDH1/2 mutation and codeletion of chromosome arms 1p/19q. Although previous studies identified CIC , FUBP1 , and TERTp as frequently altered in oligodendrogliomas, the clinical relevance of these molecular signatures is unclear. Moreover, previous studies predominantly used research panels that are not readily available to providers and patients. Accordingly, we explore genomic alterations in molecularly defined oligodendrogliomas using clinically standardized next-generation sequencing (NGS) panels.

METHODS

A retrospective single-center study evaluated adults with pathologically confirmed IDH -mutant, 1p/19q-codeleted oligodendrogliomas diagnosed between 2005 and 2021. Genetic data from formalin-fixed, paraffin-embedded specimens were analyzed with the NGS Solid Tumor Panel at the Johns Hopkins Medical Laboratories, which tests more than 400 cancer-related genes. Kaplan-Meier plots and log-rank tests compared progression-free survival (PFS) and overall survival by variant status. χ 2 tests, t -tests, and Wilcoxon rank-sum tests were used to compare clinical characteristics between genomic variant status in the 10 most frequently altered genes.

RESULTS

Two hundred and seventy-seven patients with molecularly defined oligodendrogliomas were identified, of which 95 patients had available NGS reports. Ten genes had 9 or more patients with a genomic alteration, with CIC , FUBP1 , and TERTp being the most frequently altered genes (n = 60, 23, and 22, respectively). Kaplan-Meier curves showed that most genes were not associated with differences in PFS or overall survival. At earlier time points (PFS <100 months), CIC alterations conferred a reduction in PFS in patients ( P = .038).

CONCLUSION

Our study confirms the elevated frequency of CIC , FUBP1 , and TERTp alterations in molecularly defined oligodendrogliomas and suggests a potential relationship of CIC alteration to PFS at earlier time points. Understanding these genomic variants may inform prognosis or therapeutic recommendations as NGS becomes routine.

Use of metabolic imaging to monitor heterogeneity of tumour response following therapeutic mTORC1/2 pathway inhibition

The PI3K-mTOR-AKT pathway regulates tumour proliferation, gene expression and metabolism, but pathway inhibition induces heterogeneous feedback reactivation, limiting anti-tumour responses. Measuring heterogeneity of pathway inhibition in tissues using protein biomarker phosphorylation or location is challenging. An integrated multi-modal imaging workflow was developed to assess the heterogeneity of AZD2014 (mTORC1/2 inhibitor) response in a PTEN-null renal cancer model. Spatial responses of metabolite biomarkers were analysed by mass spectrometry imaging (MSI). Control and treated tumours were classified according to metabolite-defined regions enriched in control versus AZD2014-treated tumours, respectively. Noticeably, AZD2014-treated tumours retained regions similar to regions dominant in untreated tumours. Imaging mass cytometry analysis of protein biomarkers in 'control-like' regions following AZD2014 treatment showed reduced phospho-S6, indicating suppression, but retained high expression of the glucose transporter GLUT1. Increasing PI3K-AKT inhibition by combining with AZD8186 (PI3Kβ inhibitor) further decreased the control-like metabolic signature, showing PI3K-dependent resistance. This demonstrates that MSI-based workflows yield novel insights into the pharmacodynamic effects of mTORC1/2 inhibition in tumours, which classical biomarkers do not resolve. Coupling these workflows with spatial-omics approaches can deliver greater insights into heterogeneity of treatment response.

Atezolizumab and Bevacizumab prior to liver transplantation in hepatic angiosarcoma mimicking hepatocellular carcinoma

Hepatic angiosarcoma is a rare yet aggressive malignancy, which is prone to misdiagnosis due to the lack of specific molecular and radiological characteristics. The treatment regimens remain controversial and disappointing. Randomized clinical trials are limited due to the rarity of this specific aggressive malignancy. Independent case reports or series can provide relevant references for treatment. We reported the very first hepatic angiosarcoma received Atezolizumab and Bevacizumab as a first-line treatment prior to liver transplantation, which resulted in a partial pathological response under specific molecular mutations. This case illustrates the potential role of immune checkpoint inhibitor combined with anti-angiogenic therapy as an off-label treatment option warranting further investigation.

Correlation Between PIK3R1 Expression and Cell Growth in Human Breast Cancer Cell Line BT-474 and Clinical Outcomes

Background

While mutations in the PIK3CA gene play important roles in human breast carcinogenesis, PIK3R1 gene alterations are recognized as actionable mutations for clinical cancer treatment. We aimed to elucidate the role of PIK3R1 in cell proliferation on breast carcinoma and to correlate the PIK3R1 expression with patients' outcome using human tumor tissue arrays.

Methods

Using human BT-474 (estrogen receptor (ER)+/human epidermal growth factor receptor 2 (HER2)-high) breast carcinoma cell line as in vitro model, the role of PIK3R1 in cell proliferation was elucidated by knock-down of the PIK3R1 gene (ΔPIK3R1) in this cell line. Between January 2000 to December 2015, the records of a cohort of 440 patients in our hospital were retrospectively reviewed, including patients' survival. The correlations between PIK3R1 expression and patient prognosis, such as overall survival (OS) and disease-free survival (DFS), were elucidated by human breast cancer tumor tissue array immunostaining.

Results

After the PIK3R1 gene was silenced in the BT-474 line, there was an increased cell number and a decrease in the G0G1-fraction, and increased S-fraction and the S+G2M-fraction for the ΔPIK3R1-BT-474 cell line, as compared to their cell wild type (WT) line. Western blot analysis showed that decreased PIK3R1 protein levels were accompanied by an increase of the p-AKT and p-mTOR proteins in the ΔPIK3R1-BT-474 cell line, compared to the equivalent WT line. Using a human tumor tissue array, patients with high-expressed PIK3R1 protein had better outcomes in terms of DFS and OS, compared to those with low-expressed PIK3R1 protein, when breast cancer was at an early stage (stage I/II), but not across all stages of breast cancer in human patients.

Conclusions

We concluded that downregulated PIK3R1 in BT-474 cells resulted in an increased cell growth and upregulated AKT-mTOR signaling. Clinically, the high-expressed PIK3R1 protein in tumors correlates positively with patients' outcome in stage I and II breast cancer.

Phase Ib study of the oral PI3Kδ inhibitor linperlisib in patients with advanced solid tumors

BACKGROUND

Patients with advanced solid tumors have a suboptimal prognosis. This study investigated the safety and feasibility of linperlisib, a selective phosphatidylinositol 3-kinase delta isoform (PI3Kδ) inhibitor, for treating patients with advanced solid tumors.

METHODS

In this phase Ib, single-arm, open-label, multi-center clinical trial, patients with histologically confirmed advanced solid tumors from eight centers in China were enrolled to receive oral linperlisib (80 mg/day). The primary endpoint was safety.

RESULTS

Between August 2019 and June 2022, 94 patients were enrolled in the trial and received the study treatment. The most common (≥ 20%) treatment emergent adverse events (TEAEs) of all grades irrespective of causality were increased aspartate aminotransferase (AST) (26.6%), proteinuria (26.6%), decreased appetite (25.5%), increased alanine aminotransferase (ALT) (22.3%), weight loss (21.3%), and anemia (21.3%). The most common grade ≥ 3 TEAEs were diarrhea (4.3%), increased AST (3.2%), increased ALT (3.2%), neutropenia (3.2%), anemia (3.2%), increased blood alkaline phosphatase (3.2%). The objective response rate (ORR) was 1.1% (95% confidence interval [CI] 0.0-5.8), and the disease control rate (DCR) was 37.2% (95% CI 27.5-47.8). As of the data cutoff, the median follow-up time was 4.2 months (95% CI 2.8-6.9). The median progression-free survival (PFS) was 1.85 months (95% CI 1.79-1.88). The median overall survival (OS) was not reached.

CONCLUSION

Linperlisib showed an acceptable safety profile and preliminary clinical benefit in patients with a range of advanced solid tumors. Further studies of linperlisib safety and efficacy are warranted.

Non-Hotspot PIK3CA Variants Have Higher Variant Allele Frequency and are More Common in Syndromic Vascular Malformations

PIK3CA variants are known to cause vascular malformations. We were interested in studying the phenotypic spectrum, the location within the PIK3CA gene, and the variant allele frequency (VAF) of somatic PI3KCA variants in vascular malformations. Clinical data of consecutive patients with extracranial/extraspinal vascular malformations were collected in the context of the VASCOM cohort (2008-2022, n = 558). Starting October 2020, biopsy samples were tested with the TSO500 gene panel (Illumina). All consenting patients with PIK3CA variants were included in this study. Eighty-nine patients had available genetic results by June 2022. PIK3CA variants (n = 25) were found in 16 simple/combined (nonsyndromic) vascular malformations and in nine vascular malformations associated with other anomalies (syndromic). Four hotspot variants in exons 9 and 20 (c.1624G>A, c.1633G>A, c.3140A>G, c.3140A>T) were identified in 16/25 patients (VAF 0.9%-9.7%). Six non-hotspot variants (c.328_330del, c.323_337del, c.353G>A, c.1258T>C, c.3132T>A, c.3195_3203delinsT) were detected in nine patients (VAF 3.6%-31.7%). Non-hotspot variants were more frequent in syndromic than nonsyndromic vascular malformations (p = 0.0034) and exhibited a higher VAF than hotspot variants (p = 0.0253). Our study contributes to the growing body of knowledge of the genetic background in vascular malformations. Further studies will enrich the ever-growing list of pathogenic PIK3CA variants associated with vascular malformations.

MET Activation in Lung Cancer and Response to Targeted Therapies

The hepatocyte growth factor receptor (MET) is a receptor tyrosine kinase (RTK) that mediates the activity of a variety of downstream pathways upon its activation. These pathways regulate various physiological processes within the cell, including growth, survival, proliferation, and motility. Under normal physiological conditions, this allows MET to regulate various development and regenerative processes; however, mutations resulting in aberrant MET activity and the consequent dysregulation of downstream signaling can contribute to cellular pathophysiology. Mutations within MET have been identified in a variety of cancers and have been shown to mediate tumorigenesis by increasing RTK activity and downstream signaling. In lung cancer specifically, a number of patients have been identified as possessing MET alterations, commonly receptor amplification (METamp) or splice site mutations resulting in loss of exon 14 (METex14). Due to MET's role in mediating oncogenesis, it has become an attractive clinical target and has led to the development of various targeted therapies, including MET tyrosine kinase inhibitors (TKIs). Unfortunately, these TKIs have demonstrated limited clinical efficacy, as patients often present with either primary or acquired resistance to these therapies. Mechanisms of resistance vary but often occur through off-target or bypass mechanisms that render downstream signaling pathways insensitive to MET inhibition. This review provides an overview of the therapeutic landscape for MET-positive cancers and explores the various mechanisms that contribute to therapeutic resistance in these cases.

Current developments in PI3K-based anticancer agents: Designing strategies, biological activity, selectivity, structure-activity correlation, and docking insight

The phospatidylinositol-3 kinase (PI3K) pathway is a critical intracellular signalling mechanism that is changed or amplified in a variety of cancers, including breast, gastric, ovarian, colorectal, prostate, glioma, and endometrial. PI3K signalling is important for cancer cell survival, angiogenesis, and metastasis, making it a promising therapeutic target. The PI3K kinases in their different isoforms, namely α, β, δ, and γ, encode PIK3CA, PIK3CB, PIK3CD, and PIK3CG genes. Specific gene mutation or overexpression of the protein is responsible for the therapeutic failure of current therapeutics. There are several current and completed clinical trials using PI3K inhibitors (pan, isoform-specific, and dual PI3K/mTOR) to develop effective PI3K inhibitors capable of overcoming resistance to existing drugs. However, the bulk of these inhibitors have had their indications revoked or voluntarily withdrawn due to concerns about their harmful consequences. Several inhibitors containing medicinally privileged scaffolds like thiazole, triazine, benzimidazole, podophyllotoxin, pyridine, quinazoline, thieno-triazole, pyrimidine, triazole, benzofuran, imidazo-pyridazine, oxazole, coumarin, and azepine derivatives have been explored to target the PI3K pathway and/or a specific isoform in the current overview. This article reviews the structure, biological activities, and clinical status of PI3K inhibitors. It focuses on the development techniques, docking insight, and structure-activity connections of PI3K-based inhibitors. The findings provide useful insights and future approaches for the development of promising PI3K-based inhibitors.

Cerebral Cavernous Malformation: From Genetics to Pharmacotherapy

INTRODUCTION

Cerebral cavernous malformation (CCM) is a type of cerebrovascular abnormality in the central nervous system linked to both germline and somatic genetic mutations. Recent preclinical and clinical studies have shown that various drugs can effectively reduce the burden of CCM lesions. Despite significant progress, the mechanisms driving CCM remain incompletely understood, and to date, no drugs have been developed that can cure or prevent CCM. This review aims to explore the genetic mutations, molecular mechanisms, and pharmacological interventions related to CCM.

METHODS

Literatures on the genetic mechanisms and pharmacological treatments of CCM can be searched in PubMed and Web of Science.

RESULTS

Germline and somatic mutations mediate the onset and development of CCM through several molecular pathways. Medications such as statins, fasudil, rapamycin, and propranolol can alleviate CCM symptoms or hinder its progression by specifically modulating the corresponding targets.

CONCLUSIONS

Understanding the molecular mechanisms underlying CCM offers potential for targeted therapies. Further research into novel mutations and treatment strategies is essential for improving patient outcomes.

Improved production of class I phosphatidylinositol 4,5-bisphosphate 3-kinase

Phosphatidylinositol 4,5-bisphosphate 3-kinases (PI3K) are a family of kinases whose activity affects pathways needed for basic cell functions. As a result, PI3K is one of the most mutated genes in all human cancers and serves as an ideal therapeutic target for cancer treatment. Expanding on work done by other groups we improved protein yield to produce stable and pure protein using a variety of modifications including improved solubility tag, novel expression modalities, and optimized purification protocol and buffer. By these means, we achieved a 40-fold increase in yield for p110α/p85α and a 3-fold increase in p110α. We also used these protocols to produce comparable constructs of the β and δ isoforms of PI3K. Increased yield enhanced the efficiency of our downstream high throughput drug discovery efforts on the PIK3 family of kinases.

Molecular Basis of Oncogenic PI3K Proteins

The dysregulation of phosphatidylinositol 3-kinase (PI3K) signaling plays a pivotal role in driving neoplastic transformation by promoting uncontrolled cell survival and proliferation. This oncogenic activity is primarily caused by mutations that are frequently found in PI3K genes and constitutively activate the PI3K signaling pathway. However, tumorigenesis can also arise from nonmutated PI3K proteins adopting unique active conformations, further complicating the understanding of PI3K-driven cancers. Recent structural studies have illuminated the functional divergence among highly homologous PI3K proteins, revealing how subtle structural alterations significantly impact their activity and contribute to tumorigenesis. In this review, we summarize current knowledge of Class I PI3K proteins and aim to unravel the complex mechanism underlying their oncogenic traits. These insights will not only enhance our understanding of PI3K-mediated oncogenesis but also pave the way for the design of novel PI3K-based therapies to combat cancers driven by this signaling pathway.

The additive interaction of healthy lifestyles and genetic susceptibility on colorectal cancer risk in prediabetes: a large population-based prospective cohort study

OBJECTIVE

We aimed to investigate the interrelationships among polygenic risk scores (PRS), healthy lifestyle factors (HLFs), and colorectal cancer (CRC) risk in individuals with prediabetes. To investigate whether adherence to HLFs influence CRC risk in those with elevated PRS within this specific population.

METHODS

Data from 22,408 prediabetes participants without CRC at baseline were analyzed from the UK Biobank. HLFs were graded using healthy lifestyle scores (HLSs) and classified as favorable, intermediate, or unfavorable, while the PRS for CRC was categorized as high, medium, or low. Cox proportional hazards models were used to calculate hazard ratios (HR) and 95% confidence intervals (CI) for CRC risk.

RESULTS

High PRS (HR: 2.36; 95% CI: 1.86-3.00) and medium PRS (HR: 1.42; 95% CI: 1.09-1.83) prediabetes were associated with increased CRC risk compared to those with low PRS. HLFs were linked to lower CRC risk in a dose-response manner, with never smoking (HR: 0.69; 95% CI: 0.57-0.84) and maintaining a healthy BMI (HR: 0.64; 95% CI: 0.49-0.82) associated with reduced CRC risk. Adherence to favorable HLFs may reduce the CRC risk in those with medium (HR: 0.51; 95% CI: 0.27-0.95) and high PRS (HR: 0.62; 95% CI: 0.39-0.99) over 15 years of follow-up. In participants with high PRS and unfavorable HLFs, the excess risk due to the additive interaction between PRS and HLFs was 1.41% (p < 0.01), especially for women (1.07%).

CONCLUSIONS

There is an additive interaction of PRS and HLFs on CRC risk in individuals with prediabetes. Adopting favorable HLFs should be integrated into the management of prediabetes individuals to reduce the risk of CRC.

Recent advancements in biomarkers and molecular diagnostics in hormonal receptor-positive breast cancer

Molecular applications have limited use in breast cancer compared to other cancer types. In recent years, with an improving appreciation of the molecular genetics of breast cancer and innovative novel targeted and immune-mediated therapeutics, opportunities have arisen for more biomarker analysis and molecular applications in the diagnosis and treatment of both locally advanced and metastatic breast cancers. In hormone receptor-positive, HER2-negative breast cancers, a growing number of revolutionized personalized therapies are in clinical use or on trials, such as CDK4/6 inhibitors and immune checkpoint inhibitors in adjuvant and neoadjuvant settings, and PIK3CA inhibitors in metastatic disease. In this review, we focus on biomarkers associated with those new therapeutic targets and molecular applications for genetic alterations associated with drug resistance or interaction from a pathology perspective for selecting and optimizing breast cancer treatment.

Rapid, potent, and persistent covalent chemical probes to deconvolute PI3Kα signaling

Chemical probes have gained importance in the elucidation of signal transduction in biology. Insufficient selectivity and potency, lack of cellular activity and inappropriate use of chemical probes has major consequences on interpretation of biological results. The catalytic subunit of phosphoinositide 3-kinase α (PI3Kα) is one of the most frequently mutated genes in cancer, but fast-acting, high-quality probes to define PI3Kα's specific function to clearly separate it from other class I PI3K isoforms, are not available. Here, we present a series of novel covalent PI3Kα-targeting probes with optimized intracellular target access and kinetic parameters. On-target TR-FRET and off-target assays provided relevant kinetic parameters (k chem, k inact and K i) to validate our chemical probes. Additional intracellular nanoBRET tracer displacement measurements showed rapid diffusion across the cell membrane and extremely fast target engagement, while investigations of signaling downstream of PI3Kα via protein kinase B (PKB/Akt) and forkhead box O (FOXO) revealed blunted pathway activity in cancer cell lines with constitutively activated PI3Kα lasting for several days. In contrast, persistent PI3Kα inhibition was rapidly bypassed by other class I PI3K isoforms in cells lacking functional phosphatase and tensin homolog (PTEN). Comparing the rapidly-diffusing, fast target-engaging chemical probe 9 to clinical reversible PI3Kα-selective inhibitors alpelisib, inavolisib and 9r, a reversible analogue of 9, revealed 9's superior potency to inhibit growth (up to 600-fold) associated with sustained suppression of PI3Kα signaling in breast cancer cell lines. Finally, using a simple washout protocol, the utility of the highly-selective covalent PI3Kα probe 9 was demonstrated by the quantification of the coupling of insulin, EGF and CXCL12 receptors to distinct PI3K isoforms for signal transduction in response to ligand-dependent activation. Collectively, these findings along with the novel covalent chemical probes against PI3Kα provide insights into isoform-specific functions in cancer cells and highlight opportunities to achieve improved selectivity and long-lasting efficacy.

PIK3CA Mutations and Co-Mutations in Operated Non-Small Cell Lung Carcinoma

Background: Understanding PIK3CA mutations and co-mutations in non-small cell lung carcinoma (NSCLC) is critical to developing personalized treatment strategies. Therefore, this study aims to investigate PIK3CA mutations and the accompanying somatic variations in NSCLC. Methods: This retrospective study included 98 patients over 18 years of age who were diagnosed with NSCLC, operated on, and referred to the Molecular Pathology Laboratory between January 2019 and June 2024 for next-generation sequencing panel tests and ALK-ROS1 FISH analysis. Results: All patients were found to carry PIK3CA mutations. Among the 98 NSCLC patients analyzed, 16 (16.33%) were female and 82 (83.67%) were male. The average age of the patients was 64.53 ± 9.63 years, with an age range of 38-84 years, and the majority were 50 years or older. Of the cases, 51 presented the adenocarcinoma subtype, while the remaining 47 showed the squamous cell carcinoma subtype. A smoking history was present in 77 (78.57%) patients, while 21 (21.43%) had no smoking history. The most frequently detected pathogenic or likely pathogenic PIK3CA variations were c.1633G>A p.E545K (32.65%), c.1624G>A p.E542K (11.22%), c.3140A>G p.H1047R (11.22%), c.3140A>T p.H1047L (5.10%), c.1357G>C p.E453Q (4.08%), and c.3143A>G p.H1048R (2.04%). The top 10 mutations that most commonly accompanied PIK3CA variations were KRAS, NF1, TP53, EGFR, PTEN, BRAF, KIT, CDKN2A, SMARCA4, and ATM mutations, respectively. Conclusions:PIK3CA variations, along with other gene variations, may influence cancer progression and thus may play a crucial role in the determination of targeted treatment strategies.

Molecular characteristics of advanced colorectal cancer and multi-hit PIK3CA mutations

INTRODUCTION

Approximately 20% of patients living with colorectal cancer (CRC) have activating mutations in their tumors in the PIK3CA oncogene. Two or more activating mutations (multi-hit) for the PIK3CA allele increase PI3K⍺ signaling compared to single-point mutations, resulting in exceptional response to PI3K⍺ inhibition. We aimed to identify the prevalence of PIK3CA multi-hit mutations in metastatic CRC to identify patients who may benefit from PI3K inhibitors.

METHODS

The Foundation Medicine database (Boston, MA, USA) was analyzed for patients with CRC who underwent genomic profiling on tumor DNA isolated during routine clinical care from 2013 to 2021. Molecular and clinical variables were abstracted for patients with PIK3CA mutations.

RESULTS

We identified 49 051 patients with CRC who underwent Foundation Medicine testing. 710/41154 (1.7%) patients had multi-hit PIK3CA mutations, of which 53% were male (n = 448) with a median age of 60. Microsatellite status was available for 697 patients with multi-hit PIK3CA and 17.6% (123/697) were microsatellite instability-high. Clinically relevant mutations in KRAS and BRAFV600E were seen in 459/710 (64.7%) and 65/710 (9.1%), respectively. The 4 most common PIK3CA variants were H1047R (9.8%), E545K (9.2%), E542K (9.0%), and R88Q (7.1%). The most common variant pair was E542K-E545K (4.7%).

CONCLUSIONS

Multi-hit mutations in PIK3CA are seen in 1.7% of advanced CRC, a meaningful prevalence given the high burden of CRC worldwide, and may represent a subset of patients that have enhanced sensitivity to PI3K inhibition. Future investigation regarding the clinical utility of PI3K inhibitors is warranted in multi-hit PIK3CA CRC.

Molecular Profiling of Endocrine Resistance in HR+/HER2-Metastatic Breast Cancer: Insights from Extracellular Vesicles-Derived DNA and ctDNA in Liquid Biopsies

Standard treatments in hormone receptor-positive (HR+)/HER2-metastatic breast cancer (mBC) typically involve endocrine therapy (ET) combined with CDK4/6 inhibitors, yet resistance to ET remains a persistent challenge in advanced cases. A deeper knowledge of the use of liquid biopsy is crucial for the implementation of precision medicine in mBC with real-time treatment guidance. Our study assesses the prognostic value of PIK3CA and ESR1 mutations in DNA derived from extracellular vesicles (EV-DNA) in longitudinal plasma from 59 HR+/HER2-mBC patients previously exposed to aromatase inhibitors, with a comparative analysis against circulating tumor DNA (ctDNA). Mutations were evaluated by digital PCR. PIK3CA and ESR1 mutations were found in 22 and 25% of patients. Baseline ESR1 mutations in EV-DNA were associated with shorter progression-free survival (PFS) across the cohort, with the Y537S mutation showing a particularly strong impact on the outcome of fulvestrant-treated patients. In contrast, PIK3CA mutations in EV-DNA did not significantly correlate with PFS, whereas in ctDNA, they were linked to poor outcomes. Altogether, this study positions EV-DNA as a valuable biomarker alongside ctDNA, enriching the understanding of different analytes in liquid biopsy and supporting strategies for HR+/HER2-mBC in precision oncology.

Predict the Drug-Drug Interaction of a Novel PI3Kα/δ Inhibitor, TQ-B3525, and Its Two Metabolites Using Physiologically Based Pharmacokinetic Modeling

A novel dual PI3K α/δ inhibitor, TQ-B3525, has been developed for the targeted treatment of lymphoma and solid tumors. TQ-B3525 is primarily metabolized by CYP3A4 and FOM3, while also serving as a substrate for the P-glycoprotein transporter. The aim of this study was to anticipate the drug-drug interaction (DDI) of TQ-B3525 and its two metabolites with CYP3A4 enzyme potent inducer (rifampicin) and CYP3A4/P-gp inhibitor (itraconazole) utilizing a physiologically based pharmacokinetic (PBPK) modeling approach. Clinical data from healthy and cancer patient adults were employed to construct and evaluate the PBPK model for TQ-B3525, M3, and M8-3. Models involving rifampicin combined with midazolam, itraconazole combined with midazolam or digoxin were utilized to showcase the robustness of evaluating DDI effects. The simulated drug exposure of TQ-B3525, M3, and M8-3 in healthy and patient adults were consistent with clinical data, and the mean fold error values were within the acceptable ranges. The simulated results of positive substrates correspond to those reported in the literature. Co-administration with rifampicin reduces Cmax and AUC of TQ-B3525 to 76.1% and 46.0%, while increasing the levels of M3 and M8-3. With itraconazole, Cmax and AUC of TQ-B3525 rise to 131% and 204%, but decrease substantially for M3 and M8-3. PBPK model simulation results showed that the systemic exposure of TQ-B3525 was significantly affected when co-administered with CYP3A4/P-gp inducers and inhibitors. This indicates that the combination with strong inducers and inhibitors should be carefully avoided or adjust the dosage of TQ-B3525 in clinic.

A therapeutic algorithm guiding subsequent therapy selection after CDK4/6 inhibitors' failure: A review of current and investigational treatment for HR+/Her2- breast cancer

The first-line combination therapies utilizing cyclin-dependent kinase 4 and 6 inhibitors (CDK4/6i) with endocrine therapy (ET) have significantly impacted the course of hormone receptor positive (HR+)/Human Epidermal Growth Factor Receptor 2 negative (HER2-) advanced breast cancer (ABC). However, resistance often emerges, leading to a molecularly different disease. Estrogen receptor one (ESR1) gene mutations, driving resistance to aromatase inhibitors (AIs), may guide the use of fulvestrant or emerging oral selective estrogen receptor degraders (SERDs) like elacestrant. The dynamic nature of ESR1 mutations suggests potential guidance for continuing CDK4/6i therapy beyond progression. Targeting mutations like breast cancer gene 1 and 2 (BRCA 1/2) with Poly (ADP-ribose) polymerase (PARP) inhibitors or the PI3K/AKT/mTOR pathway provides therapeutic options. The advent of antibody-drug conjugates (ADCs) like trastuzumab deruxtecan (T-DXd) and novel agents targeting Trophoblast cell surface antigen-2 (Trop-2) introduces further complexity, underscoring the need for early intervention targeting specific genomic alterations in metastatic BC.

Carotenoids as modulators of the PI3K/Akt/mTOR pathway: innovative strategies in cancer therapy

Cancer progression is primarily driven by the uncontrolled activation of cellular signaling pathways, with the PI3K/Akt/mTOR (PAMT) pathway playing a central role. This pathway significantly contributes to the proliferation and survival of cancer cells, and its hyperactivity is a major challenge in managing several types of malignancies. This article delves into the promising potential of carotenoids, natural pigments found in abundance in fruits and vegetables, as a novel therapeutic strategy for cancer treatment. By specifically targeting and inhibiting the PAMT pathway, carotenoids may effectively disrupt the growth and survival of cancer cells. The article examines the complex mechanisms underlying these interactions and highlights the obstacles faced in cancer treatment. It proposes a compelling approach to developing therapies that leverage natural products to target this critical pathway, offering a fresh perspective on cancer treatment. Further research is essential to enhance the therapeutic efficacy of these compounds.

BIRC3 induces the phosphoinositide 3-kinase-Akt pathway activation to promote trastuzumab resistance in human epidermal growth factor receptor 2-positive gastric cancer

BACKGROUND

Trastuzumab-targeted therapy is currently the standard of care for advanced human epidermal growth factor receptor 2 (HER2)-positive gastric cancer. However, the emergence of resistance to trastuzumab poses significant challenges.

AIM

To identify the key genes associated with trastuzumab resistance. These results provide a basis for the development of interventions to address drug resistance and improve patient outcomes.

METHODS

High-throughput sequencing and bioinformatics were used to identify the differentially expressed pivotal gene BIRC3 and delineate its potential function and pathway regulation. Tumor samples were collected from patients with HER2-positive gastric cancer to evaluate the correlation between BIRC3 expression and trastuzumab resistance. We established gastric cancer cell lines with both highly expressed and suppressed levels of BIRC3, followed by comprehensive in vitro and in vivo experiments to confirm the involvement of BIRC3 in trastuzumab resistance and to elucidate its underlying mechanisms.

RESULTS

In patients with HER2-positive gastric cancer, there is a significant correlation between elevated BIRC3 expression in tumor tissues and higher T stage, tumor node metastasis stage, as well as poor overall survival and progression-free survival. BIRC3 is highly expressed in trastuzumab-resistant gastric cancer cell lines, where it inhibits tumor cell apoptosis and enhances trastuzumab resistance by promoting the phosphorylation and activation of the phosphoinositide 3-kinase-Akt (PI3K-AKT) pathway in HER2-positive gastric cancer cells, both in vivo and in vitro.

CONCLUSION

This study revealed a robust association between high BIRC3 expression and an unfavorable prognosis in patients with HER2-positive gastric cancer. Thus, the high expression of BIRC3 stimulated PI3K-AKT phosphorylation and activation, stimulating the proliferation of HER2-positive tumor cells and suppressing apoptosis, ultimately leading to trastuzumab resistance.