Zhihua Liu

Systematic benchmarking of high-throughput subcellular spatial transcriptomics platforms across human tumors

Abstract Recent advancements in spatial transcriptomics technologies have significantly enhanced resolution and throughput, underscoring an urgent need for systematic benchmarking. Here, we generate serial tissue sections from colon adenocarcinoma, hepatocellular carcinoma, and ovarian cancer samples for systematic evaluation. Using these uniformly processed samples, we generate spatial transcriptomics data across four high-throughput platforms with subcellular resolution: Stereo-seq v1.3, Visium HD FFPE, CosMx 6K, and Xenium 5K. To establish ground truth datasets, we profile proteins on tissue sections adjacent to all platforms using CODEX and perform single-cell RNA sequencing on the same samples. Leveraging manual nuclear segmentation and detailed annotations, we systematically assess each platform’s performance across capture sensitivity, specificity, diffusion control, cell segmentation, cell annotation, spatial clustering, and concordance with adjacent CODEX. The uniformly generated and processed multi-omics dataset could advance computational method development and biological discoveries. The dataset is accessible via SPATCH, a user-friendly web server for visualization and download.

OTUB2 silencing promotes ovarian cancer via mitochondrial metabolic reprogramming and can be synthetically targeted by CA9 inhibition

Ovarian cancer is an aggressive gynecological tumor characterized by a high relapse rate and chemoresistance. Ovarian cancer exhibits the cancer hallmark of elevated glycolysis, yet effective strategies targeting cancer cell metabolic reprogramming to overcome therapeutic resistance in ovarian cancer remain elusive. Here, we revealed that epigenetic silencing of Otubain 2 (OTUB2) is a driving force for mitochondrial metabolic reprogramming in ovarian cancer, which promotes tumorigenesis and chemoresistance. Mechanistically, OTUB2 silencing destabilizes sorting nexin 29 pseudogene 2 (SNX29P2), which subsequently prevents hypoxia-inducible factor-1 alpha (HIF-1α) from von Hippel–Lindau tumor suppressor-mediated degradation. Elevated HIF-1α activates the transcription of carbonic anhydrase 9 (CA9) and drives ovarian cancer progression and chemoresistance by promoting glycolysis. Importantly, pharmacological inhibition of CA9 substantially suppressed tumor growth and synergized with carboplatin in the treatment ofOTUB2-silenced ovarian cancer. Thus, our study highlights the pivotal role of OTUB2/SNX29P2 in suppressing ovarian cancer development and proposes that targeting CA9-mediated glycolysis is an encouraging strategy for the treatment of ovarian cancer.

RUNX1-IT1 acts as a scaffold of STAT1 and NuRD complex to promote ROS-mediated NF-κB activation and ovarian cancer progression

Dysregulated expression of long-stranded non-coding RNAs is strongly associated with carcinogenesis. However, the precise mechanisms underlying their involvement in ovarian cancer pathogenesis remain poorly defined. Here, we found that lncRNA RUNX1-IT1 plays a crucial role in the progression of ovarian cancer. Patients with high RUNX1-IT1 expression had shorter survival and poorer outcomes. Notably, knockdown of RUNX1-IT1 suppressed the proliferation, migration and invasion of ovarian cancer cells in vitro, and reduced the formation of peritoneum metastasis in vivo. Mechanistically, RUNX1-IT1 bound to HDAC1, the core component of the NuRD complex, and STAT1, acting as a molecular scaffold of the STAT1 and NuRD complex to regulate intracellular reactive oxygen homeostasis by altering the histone modification status of downstream targets including GPX1. Consequently, RUNX1-IT1 activated NF-κB signaling and altered the biology of ovarian cancer cells. In conclusion, our findings demonstrate that RUNX1-IT1 promotes ovarian malignancy and suggest that targeting RUNX1-IT1 represents a promising therapeutic strategy for ovarian cancer treatment.

USP48 Sustains Chemoresistance and Metastasis in Ovarian Cancer

Background: Ubiquitin specific protease 48 (USP48) is a member of the deubiquitinating enzymes (DUBs) family. However, the function of USP48 in ovarian cancer remains unclear. Objective: The present study reveals that USP48 knockdown could significantly inhibit cell migration and invasion in ES2, 3AO and A2780 cells, without affecting cell proliferation. Methods: After carboplatin (CBP) treatment, the USP48 ablation increases the apoptosis rate, and the cleaved PARP and cleaved caspase 3 expression levels in ES2, 3AO and A2780 cells. The subcutaneous tumor and intraperitoneally injected experiments demonstrated that the USP48 knockdown significantly increases responsiveness to CBP, and alleviates the metastasis in vivo. Meanwhile, USP48 deficiency results in the improved survival of mice. Results: Finally, the analysis of clinical samples and the TCGA and Kaplan-Meier Plot database revealed that the high expression of USP48 in ovarian cancer patients is associated with poor survival and resistance to CBP therapy. Conclusion: In summary, USP48 may be a potential therapeutic target for ovarian cancer patients.

JOSD1 inhibits mitochondrial apoptotic signalling to drive acquired chemoresistance in gynaecological cancer by stabilizing MCL1

Gynaecological cancer is a main subtype of cancer in women, and acquired chemoresistance is a major contributor to the poor prognosis of gynaecological cancer, but its underlying mechanism remains ill-defined. JOSD1 has been recognized as a deubiquitinase, but its biological functions remain largely unknown, especially in the context of cancer. Here we established a chemoresistant xenograft model and acquired chemoresistant cell lines to mimic the establishment of acquired chemoresistance. We identified that JOSD1 is the most upregulated DUB during the development of chemoresistance. JOSD1 depletion led to severe apoptosis in gynaecological cancer cells both in vivo and in vitro. Mechanistically, we showed that JOSD1 deubiquitinated and stabilized MCL1 to suppress mitochondrial apoptotic signalling. JOSD1 overexpression caused chemoresistance in gynaecological cancer by upregulating the MCL1 protein. Importantly, high JOSD1 expression was correlated with poor prognosis among ovarian cancer patients, and serum JOSD1 levels could be a marker for clinical diagnosis. Our study showed that JOSD1 is a novel and critical oncogene that contributes to the acquisition of chemoresistance by inhibiting mitochondrial apoptotic signalling via MCL1 stabilization. We also suggest that JOSD1 is an ideal therapeutic target and a promising diagnostic marker.

The deubiquitinase USP11 promotes ovarian cancer chemoresistance by stabilizing BIP

Comparison between laparoscopic and abdominal radical hysterectomy for stage IB1 and tumor size <2 cm cervical cancer with visible or invisible tumors: a multicentre retrospective study

To compare 5-year disease-free survival (DFS) and overall survival (OS) rates of laparoscopic radical hysterectomy (LRH) and abdominal radical hysterectomy (ARH) for stage IB1 and tumor size <2 cm with visible or invisible tumors. We retrospectively compared the oncological outcomes of 1,484 cervical cancer patients with IB1 and tumor size <2 cm on final pathology, who received ARH (n=899) or LRH (n=585) between January 2004 and December 2016. Patients were divided into visible tumor subgroup (ARH: n=668, LRH: n=444) and invisible tumor subgroup (ARH: n=231, LRH: n=141) according to tumor type. LRH and ARH showed similar 5-year DFS and OS rates (93.3% vs. 93.1%, p=0.997; 96.2% vs. 97.5%, p=0.351) in total study population. LRH was not associated with worse 5-year DFS rate (hazard ratio [HR]=0.96; 95% confidence interval [CI]=0.58-1.58; p=0.871) or OS rate (HR=1.37; 95% CI=0.65-2.89; p=0.409) by multivariable analysis. In the visible tumor subgroups, LRH and ARH showed similar 5-year DFS and OS rates (91.9% vs. 91.9%, p=0.933; 95.0% vs. 96.9%, p=0.276), and LRH was not associated with worse 5-year DFS or OS rate (p=0.804, p=0.324). In the invisible tumor subgroups, LRH and ARH also showed similar 5-year DFS and OS rates (97.3% vs. 97.1%, p=0.815; 100% vs. 99.5%, p=0.449), and LRH was not associated with worse 5-year DFS rate (p=0.723). Among patients with stage IB1 and tumor size <2 cm, whether the tumor is visible or not, the oncological outcomes of LRH and ARH among cervical cancer patients are comparable. This suggests that LRH may be suitable for stage IB1 and tumor size <2 cm with visible or invisible tumors. International Clinical Trials Registry Platform Identifier: CHiCTR180017778.

Targeting de novo pyrimidine synthesis confers vulnerability to copper-mediated ATR inactivation in PARP inhibitor-resistant ovarian cancer

Although poly(ADP-ribose) polymerase (PARP) inhibitors (PARPi) as monotherapy or in combination with other DNA-damaging agents exhibit promising clinical efficacy, the therapeutic responses are usually transient, with subsequent development of acquired resistance posing a significant challenge. Here, through a small-molecule compound screening, we identify elesclomol, a potent copper ionophore, which sensitizes BRCA-proficient ovarian cancer cells to PARPi by inhibiting activation of the ATR-CHK1 pathway. Mechanistically, we demonstrate that copper directly binds to ATRIP, a critical cofactor of ATR activation, disrupting the ATR-ATRIP interaction, further impairing ATR-mediated DNA damage repair signaling and potentiating PARPi sensitivity. Importantly, we reveal a secondary metabolic vulnerability in PARPi-resistant ovarian cancer associated with de novo pyrimidine synthesis, suggesting that targeting this pathway as an effective strategy to eradicate drug-adaptive residual tumors and resistant patient-derived xenograft models following ATR and PARP co-inhibition. These findings propose de novo pyrimidine synthesis as an adaptive metabolic vulnerability that can be therapeutically targeted to overcome PARPi resistance in BRCA-proficient ovarian cancer.