Biology subjects

Hemmes, A.

Publications and source records attributed to Hemmes, A..

3 recordsLinked to original sources

bioRxiv2021

PI3Kβ inhibition restores ALK inhibitor sensitivity in ALK-rearranged lung cancer

For non-small cell lung cancer (NSCLC) patients with ALK-rearranged tumors, treatment with ALK inhibitors can improve outcomes. However, clinical resistance typically develops over time, and in the majority of cases resistance mechanisms are ALK-independent. We generated tumor cell cultures from multiple regions of an ALK-rearranged clinical tumor specimen, and deployed functional drug screens to identify modulators of resistance to ALK inhibitors. This identified a role for PI3K{beta} and EGFR in regulating resistance to ALK inhibition. Furthermore, inhibition of ALK elicited activation of EGFR, and inhibition of PI3K{beta} rescued EGFR-mediated ALK inhibitor resistance. In ALK-rearranged primary cultures, cell lines and in vivo xenograft models, combined inhibition of ALK and PI3K{beta} prevented compensatory MAPK and PI3K-AKT pathway reactivation and selectively targeted the cancer cells. The combinatorial effect was seen even in the background of TP53 mutations and in epithelial-mesenchymal transformed cells. In conclusion, combinatorial ALK and PI3K{beta} inhibitor treatment carries promise as a treatment for ALK-rearranged NSCLC.

cancer biology↗

bioRxiv2020

The role of SOX9 in non-small cell lung cancer progression is histopathology-selective.

The transcription factor SOX9 is a key regulator of multiple developmental processes, and is frequently re-expressed in non-small cell lung cancer (NSCLC). Its precise role in the progression of NSCLC histopathologies has however remained elusive. We show that SOX9 expression relates to poor outcome and invasive histopathology in human adenocarcinomas, and is absent in murine early minimally invasive and human in situ adenocarcinoma. Interestingly, despite wide SOX9 expression across advanced NSCLC histotypes, its genetic deletion in the murine KrasG12D;Lkb1-/- model selectively disrupted only the growth of papillary NSCLC, without affecting the initiation of precursor lesions or growth of mucinous or squamous tissue. Spatial tissue phenotyping indicated a requirement of SOX9 expression for the progression of surfactant protein C-expressing progenitor cells, which gave rise to papillary tumours. Intriguingly, while SOX9 expression was dispensable for squamous tissue formation, its loss in fact led to enhanced squamous tumour metastasis, which was associated with altered collagen IV deposition in the basement membrane. Our work therefore demonstrates histopathology-selective roles for SOX9 in NSCLC progression, namely a requirement for papillary adenocarcinoma progression, but opposing metastasis-suppressing function in squamous histotype tissue. This attests to a pleiotropic SOX9 function, linked to the cell of origin and microenvironmental tissue contexts.

cancer biology↗

bioRxiv2020

Functional diagnostics using fresh uncultured lung tumor cells to guide personalized treatments

Functional profiling of a cancer patients tumor cells holds potential to tailor personalized cancer treatment. Here we report the utility of Fresh Uncultured Tumor-derived EpCAM+ epithelial Cells (FUTC) for ex vivo drug response interrogation. Analysis of murine Kras mutant FUTCs demonstrated pharmacological and adaptive signaling profiles comparable to subtype-matched cultured cells. Applying FUTC profiling on non-small cell lung cancer patient samples, we generated robust drug response data in 18 of 19 cases, where the cells exhibited targeted drug sensitivities corresponding to their oncogenic drivers. In one of these cases, an EGFR mutant lung adenocarcinoma patient refractory to osimertinib, FUTC profiling was used to guide compassionate treatment. FUTC profiling identified selective sensitivity to disulfiram and the combination of carboplatin plus etoposide and the patient received substantial clinical benefit from the treatment with these agents. We conclude that FUTC profiling provides a robust, rapid, and actionable assessment of personalized cancer treatment options.

cancer biology↗