PTGR1 expression

Approximately 10% of ccRCC patients in the TCGA cohort showed mutational signatures consistent with ERCC2 inactivation associated NER deficiency and also substantial levels of PTGR1 expression. These patients may be responsive to irofulven, a previously abandoned anticancer agent that has minimal activity in NER-proficient cells.

Our results provide valuable biomarkers for clinical testing of LP-184 in a large subset of genetically defined characterized refractory carcinomas. High PTGR1 expression and deleterious DDR mutations are present in approximately one third of PDAC making these patients ideal candidates for clinical trials of LP-184.

Additionally, we identified key transcription factors that significantly increase PTGR1 expression, such as SRF and RUNX3, providing potential new targets to address metformin resistance in PCa. In conclusion, our study sheds new light on the cellular mechanism underlying metformin resistance and the regulation of the SE-TFs-PTGR1 axis, offering potential avenues to enhance metformin's therapeutic efficacy in PCa.

H460 KEAP1/STK11 mutant cell line derived xenograft model was used to demonstrate the anti-tumor activity of LP-184. LP-184 displayed strong nanomolar potency in 7 day ex vivo treatment in a panel of patient derived lung cancer models carrying ATM, BRCA1 or CHEK1 mutations with IC50s in the range of 30 - 200 nM, which turned out to be 12-350 times superior to that of Olaparib across the same models. LP-184 is highly effective in selected molecular subsets of lung cancer in proof-of-concept ex vivo and in vivo studies, supporting its clinical development in small cell and non-small cell lung cancers. IND-enabling repeat dose GLP toxicology studies of LP-184 show it to be well tolerated in rats and dogs. A first-in-human dose escalation Phase 1A trial with LP-184 is expected to enroll all advanced solid tumors including lung cancers.

LP-184 treatment resulted in complete tumor regression (107-141% TGI) in 10/10 HR deficient triple negative breast cancer PDX models of which 7/10 were resistant Olaparib/ Niraparib and to Doxorubicin/ Cyclophosphamide. Unlike PARPi, LP-184 has striking activity in both NERD as well as HRD cancers. These strong data have prompted the development of a soon to be launched clinical trial to translate the broad preclinical anticancer activity of LP-184 in solid tumors with HR/NER pathway defects, such as pancreatic, prostate, ovarian and breast cancers.

LP-184, a small-molecule DNA-damaging agent, is known to be synthetically lethal in tumors with DNA-repair deficiencies, including tumors with ATM mutations...These MCL cell lines included cell lines resistant to ibrutinib, zanubrutinib, venetoclax, and bortezomib...Because ATM orchestrates the activities of the NER and HR pathways, MCL patients with ATM deficiencies are likely to have better responses to LP-284 treatment. Collectively, these data indicate that LP-284 is a promising preclinical DNA-damaging agent that possesses nanomolar-range anti-tumor activities in multiple and diverse MCL cell lines, with the potential to treat MCL patients who are resistant to other therapies.

> 50% of newly diagnosed GBMs fail to respond to standard of care temozolomide (TMZ) due to MGMT expression (i.e.unmethylated mgmt promoter) and essentially all GBMs ultimately develop TMZ resistance. LP-184 was also active in vitro against models of brain metastases from primary lung and breast cancers. These findings identify LP-184 as a promising new agent and support its further development for treating CNS tumors in adult and pediatric populations.

Furthermore, overexpression of PTGR1 in A549 cells increased the rate and total amount of oxo-fatty acid saturation. These findings will further facilitate the study of electrophilic fatty acid metabolism and signaling in the context of inflammatory diseases and cancer where they have been shown to have anti-inflammatory and anti-proliferative signaling properties.