PIK3CA Is Regulated by CUX1, Promotes Cell Growth and Metastasis in Bladder Cancer via Activating Epithelial-Mesenchymal Transition

The PIK3CA gene and its pivotal role in tumor tropism of triple-negative breast cancer

The PIK3CA gene is a linchpin in the intricate molecular network governing triple-negative breast cancer (TNBC) tumor tropism, serving as a focal point for understanding this aggressive disease. Anchored within the PI3K/AKT/mTOR signaling axis, PIK3CA mutations exert substantial influence, driving cellular processes that highlight the unique biology of TNBC. This review meticulously highlights the association between PIK3CA mutations and distinct TNBC subtypes, elucidating the gene's multifaceted contributions to tumor tropism. Molecular dissection reveals how PIK3CA mutations dynamically modulate chemokine responses, growth factor signaling, and extracellular matrix interactions, orchestrating the complex migratory behaviour characteristic of TNBC cells. A detailed exploration of PIK3CA-targeted strategies in the therapeutic arena is presented, outlining the current landscape of clinical trials and precision medicine approaches. As the scientific narrative converges, this review underscores the critical role of PIK3CA in shaping the molecular intricacies of TNBC tumor tropism and illuminates pathways toward tailored interventions, promising a paradigm shift in the clinical management of TNBC.

Single-center analysis of a real-world cohort of patients with metastatic urothelial carcinoma evaluated by NGS: molecular landscape and efficacy of targeted therapies

PURPOSE

To describe the molecular profile of a real-world cohort of patients with metastatic urothelial carcinoma (mUC) and to evaluate the benefit of next-generation sequencing (NGS) panels in guiding therapy in patients with mUC and the outcomes of DNA-matched treatments recommended by a multidisciplinary molecular tumor board (MMTB).

METHODS

This was a single-center analysis of a real-world cohort of adult patients with mUC included in an ongoing trial that aimed to evaluate the clinical utility of NGS for solid tumors. Genomic analysis was performed for each patient, most of them using the Ion Torrent Oncomine Focus Assay. Genomic results were discussed during MMTB meetings.

RESULTS

We included 43 patients with mUC treated with platinum-based combinations and immunotherapy. Twenty-five patients (58.1%; 95% CI 43.4-72.9) had at least one tumor pathogenic alteration. The MMTB classified 16 (48.5%) of the 33 tumor pathogenic alterations found in our real-world cohort of mUC patients as ESCAT I, which is the maximum grade of actionability. After excluding patients who were not candidates for targeted therapies, the MMTB provided guidance on matched therapy for seven patients. Among these patients, three achieved a partial response for an overall response rate of 42.9%, a median progression-free survival of 7.3 months (95% CI 6.7-7.9) and a median overall survival of 10.9 months (95% CI 2.4-19.5).

CONCLUSIONS

We recommend that all patients with mUC undergo NGS at diagnosis given the high percentage of patients with pathogenic alterations in our real-world cohort and the efficacy data of patients treated with targeted therapies.

CUX1 attenuates the apoptosis of renal tubular epithelial cells induced by contrast media through activating the PI3K/AKT signaling pathway

OBJECTIVE

Contrast media (CM) is a commonly applied drug in medical examination and surgery. However, contrast-induced acute kidney injury (CIAKI) poses a severe threat to human life and health. Notably, the CUT-like homeobox 1 (CUX1) gene shows protective effects in a variety of cells. Therefore, the objective of this study was to provide a new target for the treatment of CIAKI through exploring the role and possible molecular mechanism of CUX1 in CIAKI.

METHOD

Blood samples were collected from 20 patients with CIAKI and healthy volunteers. Human kidney 2 (HK-2) cells were incubated with 200 mg/mL iohexol for 6 h to establish a contrast-induced injury model of HK-2 cells. Subsequently, qRT-PCR was used to detect the relative mRNA expression of CUX1; CCK-8 and flow cytometry to assess the proliferation and apoptosis of HK-2 cells; the levels of IL(interleukin)-1β, tumor necrosis factor alpha (TNF-α) and malondialdehyde (MDA) in cells and lactate dehydrogenase (LDH) activity in cell culture supernatant were detect; and western blot to observe the expression levels of CUX1 and the PI3K/AKT signaling pathway related proteins [phosphorylated phosphoinositide 3-kinase (p-PI3K), PI3K, phosphorylated Akt (p-AKT), AKT].

RESULTS

CUX1 expression was significantly downregulated in blood samples of patients with CIAKI and contrast-induced HK-2 cells. Contrast media (CM; iohexol) treatment significantly reduced the proliferation of HK-2 cells, promoted apoptosis, stimulated inflammation and oxidative stress that caused cell damage. CUX1 overexpression alleviated cell damage by significantly improving the proliferation level of HK-2 cells induced by CM, inhibiting cell apoptosis, and reducing the level of LDH in culture supernatant and the expression of IL-1β, TNF-α and MDA in cells. CM treatment significantly inhibited the activity of PI3K/AKT signaling pathway activity. Nevertheless, up-regulating CUX1 could activate the PI3K/AKT signaling pathway activity in HK-2 cells induced by CM.

CONCLUSION

CUX1 promotes cell proliferation, inhibits apoptosis, and reduces inflammation and oxidative stress in CM-induced HK-2 cells to alleviate CM-induced damage. The mechanism of CUX1 may be correlated with activation of the PI3K/AKT signaling pathway.

Natural History and Genomic Landscape of Chemotherapy-Resistant Muscle-Invasive Bladder Cancer

PURPOSE

Patients with residual invasive bladder cancer after neoadjuvant chemotherapy (NAC) and radical cystectomy have a poor prognosis. Data on adjuvant therapy for these patients are conflicting. We sought to evaluate the natural history and genomic landscape of chemotherapy-resistant bladder cancer to inform patient management and clinical trials.

METHODS

Data were collected on patients with clinically localized muscle-invasive urothelial bladder cancer treated with NAC and cystectomy at our institution between May 15, 2001, and August 15, 2019, and completed four cycles of gemcitabine and cisplatin NAC, excluding those treated with adjuvant therapies. Survival was estimated using the Kaplan-Meier method, and multivariable Cox proportional hazards models were used to identify predictors of recurrence-free survival (RFS). Genomic alterations were identified in targeted exome sequencing (Memorial Sloan Kettering Integrated Mutation Profiling of Actionable Cancer Targets) data from post-NAC specimens from a subset of patients.

RESULTS

Lymphovascular invasion (LVI) was the strongest predictor of RFS (hazard ratio, 2.15 [95% CI, 1.37 to 3.39]) on multivariable analysis. Patients with ypT2N0 disease without LVI had a significantly prolonged RFS compared with those with LVI (70% RFS at 5 years). Lymph node yield did not affect RFS. Among patients with sequencing data (n = 101), chemotherapy-resistant tumors had fewer alterations in DNA damage response genes compared with tumors from a publicly available chemotherapy-naïve cohort (15% v 29%; P = .021). Alterations in CDKN2A/B were associated with shorter RFS. PIK3CA alterations were associated with LVI. Potentially actionable alterations were identified in more than 75% of tumors.

CONCLUSION

Although chemotherapy-resistant bladder cancer generally portends a poor prognosis, patients with organ-confined disease without LVI may be candidates for close observation without adjuvant therapy. The genomic landscape of chemotherapy-resistant tumors is similar to chemotherapy-naïve tumors. Therapeutic opportunities exist for targeted therapies as adjuvant treatment in chemotherapy-resistant disease.

Prognostic analysis and validation of lncRNAs in bladder cancer on the basis of neutrophil extracellular traps

BACKGROUND

Complex interactions in the tumor microenvironment (TME) between bladder cancer (BLCA) and immune cells are critical for cancer progression. However, studies of neutrophil extracellular trap-associated long non-coding RNAs (NET-lncRNAs) in the TME of BLCA have not been reported. This study aims to screen for NET-lncRNAs in BLCA and to preliminarily explore their effects on BLCA development.

METHODS

The correlation of NET-related gene sets, which were identified from the cancer genome atlas (TCGA) BLCA datasets, with lncRNAs was analyzed and the prognosis-related genes were identified through random forest analysis. The least absolute shrinkage and selection operator (LASSO) model was utilized to obtain prognostic risk scores for NET-lncRNAs (NET-Score). We collected clinical BLCA samples, as well as SV-HUC-1 and BLCA cells, to validate the expression of NET-lncRNAs. Survival and independent prognostic analysis were performed. In J82 and UM-UC-3 cells, after NKILA expression was inhibited, cell proliferation and apoptosis levels were detected.

RESULTS

NET-related gene sets mainly included CREB5, MMP9, PADI4, CRISPLD2, CD93, DYSF, MAPK3, TECPR2, MAPK1 and PIK3CA. Then, four NET-lncRNAs, MAP 3 K4-AS1, MIR100HG, NKILA and THY1-AS1, were identified. NET-Score had the highest hazard ratio for BLCA. An elevated NET-Score was linked to a significant increase in immune cell infiltration and copy number variation, as well as a notable decrease in survival rate and drug sensitivity. NET-lncRNA-related genes were mainly enriched in the pathways of angiogenesis, immune response, cell cycle and T cell activation. MAP 3 K4-AS1, MIR100HG, NKILA and THY1-AS1 expressions were significantly increased in BLCA tissues. Compared with SV-HUC-1 cells, NKILA expression was elevated in J82 and UM-UC-3 cells. Inhibition of NKILA expression inhibited the proliferation and promoted apoptosis of J82 and UM-UC-3 cells.

CONCLUSIONS

Several NET-lncRNAs, including MAP 3 K4-AS1, MIR100HG, NKILA and THY1-AS1, were successfully screened in the BLCA. The NET-Score was an independent prognostic factor for BLCA. In addition, inhibition of NKILA expression suppressed BLCA cell development. The above NET-lncRNAs could serve as potential prognostic markers and targets in BLCA.

Homeobox Gene Expression Dysregulation as Potential Diagnostic and Prognostic Biomarkers in Bladder Cancer

Homeobox genes serve as master regulatory transcription factors that regulate gene expression during embryogenesis. A homeobox gene may have either tumor-promoting or tumor-suppressive properties depending on the specific organ or cell lineage where it is expressed. The dysregulation of homeobox genes has been reported in various human cancers, including bladder cancer. The dysregulated expression of homeobox genes has been associated with bladder cancer clinical outcomes. Although bladder cancer has high risk of tumor recurrence and progression, it is highly challenging for clinicians to accurately predict the risk of tumor recurrence and progression at the initial point of diagnosis. Cystoscopy is the routine surveillance method used to detect tumor recurrence. However, the procedure causes significant discomfort and pain that results in poor surveillance follow-up amongst patients. Therefore, the development of reliable non-invasive biomarkers for the early detection and monitoring of bladder cancer is crucial. This review provides a comprehensive overview of the diagnostic and prognostic potential of homeobox gene expression dysregulation in bladder cancer.

Cancer invasion and metastasis: Insights from murine pubertal mammary gland morphogenesis

Cancer invasion and metastasis accounts for the majority of cancer related mortality. A better understanding of the players that drive the aberrant invasion and migration of tumors cells will provide critical targets to inhibit metastasis. Postnatal pubertal mammary gland morphogenesis is characterized by highly proliferative, invasive, and migratory normal epithelial cells. Identifying the molecular regulators of pubertal gland development is a promising strategy since tumorigenesis and metastasis is postulated to be a consequence of aberrant reactivation of developmental stages. In this review, we summarize the pubertal morphogenesis regulators that are involved in cancer metastasis and revisit pubertal mammary gland transcriptome profiling to uncover both known and unknown metastasis genes. Our updated list of pubertal morphogenesis regulators shows that most are implicated in invasion and metastasis. This review highlights molecular linkages between development and metastasis and provides a guide for exploring novel metastatic drivers.

Analysis of the Relationship between Bladder Cancer Gene Mutation and Clinical Prognosis by High-Throughput Sequencing

OBJECTIVE

Bladder cancer is one of the most common malignant tumors in urology in China. The analysis of gene mutation in bladder cancer and its relationship with clinical characteristics and prognosis will provide a basis for accurate treatment of bladder cancer. The aim of this study was to analyze the mutations and functional regions of bladder cancer-related genes based on high-throughput sequencing, and to explore the relationship between mutations and clinicopathological features, as well as its prognosis and clinical implication.

METHODS

From April 2020 to October 2020, a total of 47 patients with bladder cancer in the Department of Urology, Affiliated Hospital of Chengde Medical College were studied. Gene sequencing was performed using Nextseq CN500 System, a high-throughput sequencing platform. The results of gene detection were described, and the relationship and clinical value of high frequency mutated genes with clinicopathological features and prognosis were systematically analyzed.

RESULTS

A total of 29 mutation genes, 61 exons, and 95 mutation sites were identified in this study. The frequencies of TP53, FGFR3, PIK3CA, ERBB2, MUC4, and KRAS mutation are relatively high, accounting for 59.92 % of the total mutation frequency. The TP53 was significantly associated with muscle invasive bladder cancer, T2 stage, and progression-free survival, while FGFR3 was significantly associated with non-muscle invasive bladder cancer and T1 stage.

CONCLUSION

High-throughput sequencing technology provides a successful approach for detecting bladder cancer gene mutations. The TP53, FGFR3, PIK3CA, ERBB2, MUC4, and KRAS genes have high mutation frequencies in bladder cancer patients. The TP53, FGFR3 and PIK3CA genes may play a predictive role in the prognosis of bladder cancer, which may hold certain guiding significance for in-depth study of the pathogenesis of bladder cancer and the development of targeted therapies.

LncRNA SNHG1 targets miR-340-5p/PIK3CA axis to regulate microvascular endothelial cell proliferation, migration, and angiogenesis in DR

Diabetic retinopathy (DR) is a serious long-term complication of diabetes. However, the current treatment of DR is still challenging. We aimed to investigate the role of lncRNA SNHG1/miR-340-5p/PIK3CA in DR and the mechanisms involved. Blood samples from clinical DR patients and healthy subjects were obtained. HRMECs were induced by high glucose for 24 h to establish the DR model. The vector for interfering or overexpressing lncRNA SNHG1, miR-340-5p, and PIK3CA was constructed. LncRNA SNHG1, miR-340-5p, and PIK3CA expressions were detected by qRT-PCR or Western blot. Cell proliferation and migration were detected by CCK-8 and Transwell assays. Blood vessel formation was detected by angiogenesis assay. Dual-luciferase reporter assay tested the interaction of lncRNA SNHG1 with miR-340-5p and miR-340-5p with PIK3CA. RIP measured the binding of miR-340-5p to PIK3CA. In the blood of DR patients and the DR model, lncRNA SNHG1 was increased and miR-340-5p expression was down-regulated. In the DR model, PIK3CA expression was elevated. Downregulation of lncRNA SNHG1 inhibited HRMECs proliferation, migration, and angiogenesis. LncRNA SNHG1 interacted with miR-340-5p, and up-regulation of miR-340-5p inhibited HRMECs proliferation, migration and angiogenesis. The inhibition of cell proliferation, migration, and angiogenesis of HRMECs caused by down-regulation of lncRNA SNHG1 was reversed by knockdown of miR-340-5p. miR-340-5p targeted PIK3CA, and downregulation of PIK3CA inhibited HRMECs proliferation, migration, and angiogenesis. The inhibition of HRMECs proliferation, migration and angiogenesis caused by down-regulation of lncRNA SNHG1 could be reversed by overexpression of PIK3CA. LncRNA SNHG1 targeted miR-340-5p/PIK3CA axis to regulate microvascular endothelial cell proliferation, migration, and angiogenesis in DR.

The expression and prognostic significance of PIK3CB in lung adenocarcinoma

OBJECTIVE

The aim of this study was to explore the expression and prognostic significance of PIK3CB in lung adenocarcinoma (LUAD) and to analyse the possible molecular mechanism that promotes LUAD development.

METHODS

Differences of PIK3CB expression at transcriptional level between LUAD and normal tissues were analysed with the Timer and UALCAN databases. Then, immunohistochemical staining was performed to investigate PIK3CB expression at the protein level, and relationships between PIK3CB and clinical characteristics were accessed. Univariate and multivariate Cox regression were performed to identify the independent prognostic risk factors for LUAD. Genetic alterations were analysed using the cBioPortal database. The main coexpressed genes and enrichment pathways of PIK3CB were estimated with the LinkedOmics database.

RESULTS

Compared with normal tissues, PIK3CB was higherly expressed in LUAD at the transcriptional level and protein level, respectively. PIK3CB expression was closely related to prognosis of LUAD patients, and PIK3CB protein expression was associated with lymph node metastasis and pathological differentiation, but not related to sex, age, pleural invasion, vascular invasion, tumour site, tumour size or clinical stage. PIK3CB and tumour size were independent risk factors for LUAD patients. The expression of PIK3CB was negatively correlated with AKT1 and AKT2, but there was no significant correlation with AKT3, and strong positive correlations with ARMC8, DNAJC13 and PIK3R4. The main enrichment pathways of PIK3CB and related genes included adherens junctions and the phosphatidylinositol signalling pathways, ErbB signalling pathways, Hedgehog signalling pathways, and C-type lectin receptor signalling pathways. Therefore, we hypothesized that PIK3CB expression did not promote LUAD development through the classical PI3K/AKT pathway.

CONCLUSION

High PIK3CB expression was associated with the development of LUAD and worse prognosis. PIK3CB was an independent risk factor for LUAD patients. Therefore, this study provides a reliable reference for the prognostic assessment and targeted therapy for LUAD patients.

A Novel Ferroptosis-Related Prognostic Signature Reveals Macrophage Infiltration and EMT Status in Bladder Cancer

Bladder cancer (BC) belongs to one of the most common and highly heterogeneous malignancies. Ferroptosis is a newly discovered regulated cell death (RCD), characterized by accumulation of toxic lipid peroxides, and plays a crucial role in tumor progression. Here, we conducted a comprehensive analysis on the transcriptomics data of ferroptosis-related genes in BC based on The Cancer Genome Atlas (TCGA) and three Gene Expression Omnibus (GEO) datasets. In our study, a 6-gene signature was identified based on the potential prognostic ferroptotic regulatory genes. Furthermore, our signature revealed a good independent prognostic ability in BC. Patients with low-risk score exhibited higher FGFR3 mutation rates while high risk score had a positive association with higher RB1 mutation rates. Meanwhile, higher proportions of macrophages were observed in high BC risk group simultaneously with four methods. Unexpectedly, the risk score showed a significant positive correlation with epithelial-mesenchymal transition (EMT) status. Functional assays indicated that CRYAB and SQLE knockdown was associated with attenuated invasion capacity. Our study revealed a ferroptosis-related risk model for predicting prognostic and BC progression. Our results indicate that targeting ferroptosis may be a therapeutic strategy for BC.

LPCAT1 Promotes Cutaneous Squamous Cell Carcinoma via EGFR-Mediated Protein Kinase B/p38MAPK Signaling Pathways

Cutaneous squamous cell carcinoma (cSCC) is the second most common form of skin cancer. LPCAT1, a lysophosphatidylcholine acyltransferase, takes a center stage in membrane lipid remodeling. LPCAT1 is elevated in several cancers and contributes to cancer development. However, its role and molecular mechanisms in cSCC remain to be elucidated. In this study, we found that LPCAT1 was upregulated in cSCC tissues and in cell lines. In vitro, loss-of-function and gain-of-function experiments demonstrated that LPCAT1 facilitated cSCC cell proliferation, protected cells against apoptosis, accelerated epithelial‒mesenchymal transition, and enhanced cell metastasis. Mechanistically, LPCAT1 regulated EGFR signaling. The oncogenic effect of LPCAT1 was mediated by EGFR/protein kinase B and EGFR/p38MAPK pathways in cSCC. Using the xenograft mouse model, we consolidated the results mentioned earlier. In conclusion, LPCAT1 contributed to cSCC progression through EGFR-mediated protein kinase B and p38MAPK signaling pathways. LPCAT1 may serve as a target for therapeutic intervention in cSCC.