The artemisinin family of compounds is cytopathic in certain cancer cell lines that are positive for human papillomaviruses (HPV) and can potentially drive the regression of dysplastic lesions. We evaluated the efficacy of topical dihydroartemisinin (DHA) on cervical dysplasia and anal dysplasia in two papillomavirus mouse models: K14E6/E7 transgenic mice, which express HPV16 oncogenes; and immunodeficient NOD/SCID gamma (NSG) mice infected with Mus musculus papillomavirus (MmuPV1). Mice started treatment with DHA at 25 weeks of age (K14E6/E7) or 20 weeks post infection (MmuPV1-infected), when the majority of mice are known to have papillomavirus-induced low- to high-grade dysplasia. Mice were treated with or without topical DHA at the cervix or anus and with or without topical treatment with the chemical carcinogen 7,12 dimethylbenz(a)anthracene (DMBA) at the anus of in transgenic mice to induce neoplastic progression. Mice were monitored for overt tumor growth, and tissue was harvested after 20 weeks of treatment and scored for severity of histological disease. For MmuPV1-infected mice, anogenital lavages were taken to monitor for viral clearance. Tissues were also evaluated for viral gene expression at the RNA and/or protein levels. Treatment with topical DHA did not reduce dysplasia in the anogenital tract in either papillomavirus-induced mouse model and did not prevent progression to anal cancer in the DMBA-treated K14E6/E7 mice.

Select protease inhibitors (PI) have been found to be effective in decreasing human papillomavirus oncoprotein expression. This study evaluated whether the topical PI, Saquinavir (SQV), promotes viral clearance in an infectious mouse model with Mus musculus papillomavirus I (MmuPV1). NOD scid gamma (NSG) mice were anally infected with similar to 4 x 10(8) viral genome equivalents of MmuPV1 and 120 days post-infection (when majority have high-grade anal dysplasia), began topical treatments: control (mock), 7,12-dimethylbenz(a)anthracene (DMBA) only, once weekly to promote carcinogenesis, 1% SQV only, daily (Monday - Friday), and SQV + DMBA. Viral MmuPV1 load was analyzed from anal lavages pre and post-treatment. Anal tissue was harvested, processed, and evaluated for drug absorption, grade of anal disease, and anal viral RNA. Results suggest that topical SQV promotes decreased viral shedding in female mice treated with SQV.

Anal cancer is a major health problem. This study seeks to determine if the topical protease inhibitor Saquinavir (SQV), is effective at the prevention of anal cancer in transgenic mice with established anal dysplasia. K14E6/E7 mice were entered into the study when the majority spontaneously developed high-grade anal dysplasia. To ensure carcinoma development, a subset of the mice was treated with a topical carcinogen: 7,12-Dimethylbenz[a]anthracene (DMBA). Treatment groups included: no treatment, DMBA only, and topical SQV with/without DMBA. After 20 weeks of treatment, anal tissue was harvested and evaluated histologically. SQV was quantified in the blood and anal tissue, and tissue samples underwent analysis for E6, E7, p53, and pRb. There was minimal systemic absorption of SQV in the sera despite high tissue concentrations. There were no differences in tumor-free survival between SQV-treated and respective control groups but there was a lower grade of histological disease in the mice treated with SQV compared to those untreated. Changes in E6 and E7 levels with SQV treatment suggest that SQV may function independently of E6 and E7. Topical SQV decreased histological disease progression in HPV transgenic mice with or without DMBA treatment without local side effects or significant systemic absorption.

Low-grade anal dysplasia is a disease that can progress to high-grade anal dysplasia and eventually anal cancer if left untreated. Research has shown that low-grade anal dysplasia is marked by significant autophagic dysfunction. We hypothesized that systemic induction of autophagy, via phosphoinositide 3-kinase/mammalian target of rapamycin (PI3K/mTOR) inhibition, would be effective in preventing anal cancer development in human papillomavirus (HPV) mice (K14E6/E7) with established low-grade anal dysplasia. Mice began treatment at 15 weeks of age, when 75% of mice spontaneously develop low-grade anal dysplasia, and were divided into the following groups: no treatment, systemic LY3023414 (4.5 mg/kg, dual PI3K/mTOR inhibitor) alone, topical 7,12 dimethylbenz[a]anthracene (DMBA) alone, or systemic LY3023414 and topical DMBA. Groups were compared for final histology, PI3K activity, mTOR activity, autophagic induction (light chain 3B (LC3β)), autophagic function (p62 protein), and tumor-free survival. Untreated mice or mice treated with LY3023414 alone did not progress to cancer. There was a statistically significant decrease in the number of mice that developed histologic evidence of cancer when comparing mice that received systemic LY3203414 with topical DMBA versus those that received topical DMBA alone (p = 0.0003). PI3K and mTOR activity decreased in groups treated with systemic LY3023414 and topical DMBA as compared with those treated with topical DMBA alone (p = 0.0005 and p = 0.0271, respectively). LC3β and p62 expression was not statistically altered with systemic LY3023414 treatment. Mice developed less overt tumors and had increased tumor-free survival when treated with systemic LY3023414 in the presence of topical DMBA compared to topical DMBA alone (p = 0.0016 and p < 0.001, respectively). Systemic LY3023414 treatment is effective in anal cancer prevention in the setting of established low-grade anal dysplasia in an HPV-associated mouse model of anal cancer.

Glucocorticoids promote muscle atrophy by inducing a class of proteins called atrogenes, resulting in reductions in muscle size and strength. In this work, we evaluated whether a mouse model with pre-existing diet-induced obesity had altered glucocorticoid responsiveness. We observed that all animals treated with the synthetic glucocorticoid dexamethasone had reduced strength, but that obesity exacerbated this effect. These changes were concordant with more pronounced reductions in muscle size, particularly in Type II muscle fibers, and potentiated induction of atrogene expression in the obese mice relative to lean mice. Furthermore, we show that the reductions in lean mass do not fully account for the dexamethasone-induced insulin resistance observed in these mice. Together these data suggest that obesity potentiates glucocorticoid-induced muscle atrophy.

KRAS G12D is a common oncogenic driver mutation in diverse cancers, including non–small cell lung cancer, colorectal cancer, and pancreatic cancer. KRASG12D inhibitors have recently progressed into clinical trials but will likely face innate or acquired drug resistance similar to that which has been observed for KRASG12C inhibitors, such as activation of receptor tyrosine kinases, KRAS independence, and reactivation of RAS–MAPK signaling. This study investigates heterobifunctional small-molecule dual inhibitors that simultaneously target both KRASG12D and protein chaperone HSP90 in KRASG12D-mutated cancer cell lines and patient-derived organoids. Our findings reveal that the efficacy of the clinical-stage KRASG12D inhibitor MRTX1133 varies, with notable resistance being observed in some cell line and organoid models. In contrast, KRASG12D–HSP90 dual inhibitors were found to broadly display superior effectiveness in inducing apoptosis, reducing cell viability, and suppressing key downstream signaling pathways such as AKT and ERK1/2 in MRTX1133-resistant models. The rationale for targeting HSP90, which is preferentially activated in cancer cells, alongside KRASG12D, arises from the ability of HSP90 inhibition to destabilize substrate client proteins that are essential for cancer cell survival and have also been implicated in resistance to KRAS inhibitors. This dual-inhibitor approach presents a promising new strategy to combat de novo and acquired drug resistance in KRASG12D-mutated cancers and potentially paves the way for improved clinical outcomes by addressing the complex molecular mechanisms underlying cancer cell evolution that enables resistance to conventional inhibitors.