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MDM2 has been established as a biomarker indicating poor prognosis for individuals undergoing immune checkpoint inhibitor (ICI) treatment for different malignancies by various pancancer studies. Specifically, patients who have MDM2 amplification are vulnerable to the development of hyperprogressive disease (HPD) following anticancer immunotherapy, resulting in marked deleterious effects on survival rates. The mechanism of MDM2 involves its role as an oncogene during the development of malignancy, and MDM2 can promote both metastasis and tumor cell proliferation, which indirectly leads to disease progression. Moreover, MDM2 is vitally involved in modifying the tumor immune microenvironment (TIME) as well as in influencing immune cells, eventually facilitating immune evasion and tolerance. Encouragingly, various MDM2 inhibitors have exhibited efficacy in relieving the TIME suppression caused by MDM2. These results demonstrate the prospects for breakthroughs in combination therapy using MDM2 inhibitors and anticancer immunotherapy., (© 2024. The Author(s).)

The purpose of this study was to investigate the efficacy and safety of programmed cell death 1 (PD-1) and programmed cell death 1 ligand (PD-L1) inhibitors using a meta-analysis of present trials for advanced melanoma. A fully recursive literature search of the primary electronic databases for available trials was performed. The objective response rate (ORR) and the median progression-free survival (PFS) of clinical responses were considered the main endpoints to evaluate the efficacy, whereas Grade 3-4 adverse effects (AEs) were analyzed to evaluate safety. The ORR of PD-1 and PD-L1 inhibitors was 30% (95% CI: 25-35%). No significant difference in the ORR was observed after the comparisons of low-dose, median-dose, and high-dose cohorts. In addition, the rate of Grade 3-4 AEs was 9% (95% CI: 6-12%). According to the 3 randomized controlled trials that compared PD-1 inhibitors with chemotherapy, the difference between these 2 groups was found to be statistically significant with respect to the ORR, PFS and the incidence of Grade 3-4 AEs; that is, the relative risk (RR) of the ORR was 3.42 (95% CI: 2.49-4.69, P < 0.001), the hazard ratio (HR) of the PFS was 0.50 (95% CI: 0.44-0.58, P < 0.001), and the RR of Grade 3-4 AEs was 0.45 (95% CI: 0.31-0.65, P < 0.001). According to a meta-analysis of limited concurrent studies, PD-1 and PD-L1 inhibitors appear to be associated with improved response rates, superior response durability and tolerable toxicity in patients with advanced melanoma.

Background: Crizotinib was granted accelerated approval by the Food and Drug Administration in 2011 for the treatment of anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer (NSCLC). To evaluate the efficacy and safety of crizotinib, we performed a meta-analysis of published clinical trials using the random effect model., Methods: The efficacy and safety of crizotinib was evaluated based on 1-year overall survival (OS), progression-free survival (PFS), overall response rate (ORR), partial response, complete response, stable disease, and dose reduction or cessation because of crizotinib toxicity., Results: Six clinical trials were included in the meta-analysis. Crizotinib treatment demonstrated a 1-year OS of 66.8% (95% CI, 52.2-78.8%) and a PFS of 8.6 months (95% CI, 7.3-9.9 months). The aggregate ORR, partial response and complete response rates were 61.2%, 59.8% and 1.5%, respectively. The proportion of patients achieving stable disease was 42.6% (95% CI, 17.3-72.5%). The most frequently reported adverse effects of crizotinib were mild visual disturbances, nausea, vomiting, diarrhea, constipation, edema, reduction in glomerular filtration rate, and generally reversible but sometimes severe elevations in aspartate aminotransferase and alanine aminotransferase. The proportion of patients who required dose reduction or cessation because of crizotinib toxicity was 6.5% (95% CI, 4.1-10.1%)., Conclusions: This meta-analysis revealed extended survival and improved response rates in patients treated with crizotinib. As a novel, targeted anticancer agent, crizotinib appears to be a favorable treatment option for patients with locally advanced or metastatic ALK-positive NSCLC.

The objective of this study was to investigate the stem cell-like properties of drug-resistant colon cancer cells. Oxaliplatin was used to induce the drug-resistant subline of HCT116(p53+/+) cell line. The stem cell-like characteristics of the drug-resistant subline were assayed for the proliferation capacity, cell cycle, adhesion, invasion, multiple drug resistance, and clone sphere formation capacity. The expression of ABCG2 (ATP-binding cassette superfamily G member 2) and "stemness" indicators SOX2 (SRY-related HMG box-containing transcription factor-2) and OCT4 (octamer-binding transcription factor 4) was determined by Western blot. We established the HCT116(p53+/+)-oxaliplatin subline (HCT116(p53+/+)OXA), which was resistant to oxaliplatin with a resistance index (RI) of 3.03 ± 0.14. The HCT116(p53+/+)OXA was also resistant to Taxol, showing lower proliferation, higher adhesion and invasion ability, greater proportion of G0/G1 phase, and higher sphere-forming capacity than its parental cells. SOX2, OCT4, and ABCG2 were expressed at higher levels in drug-resistant cells than in their parental cells. We verified that the HCT116(p53+/+)OXA was enriched with cancer stem cell properties and provided an ideal cell model for drug-resistance study.

Chidamide, the structural analog of MS-275, is a novel and promising histone deacetylase (HDAC) inhibitor for use in cancer therapy. To investigate its effects on cancer cell growth, MTT assay was performed in 10 human cancer cell lines. The data showed that the IC50 of Chidamide ranged from 1 to 13 µM, which was comparable to that of MS-275 in half of the tested cell lines. Furthermore, the growth curve indicated that cell growth was gradually inhibited with an increase in Chidamide dosage, and the inhibition was reversed after drug removal in two hepatocelluclar carcinoma cell lines, BEL-7402 and HCC-9204. To determine cell cycle and apoptosis, FACS was carried out in the BEL-7402 and HCC-9204 cells treated with Chidamide. A decrease in the cell population at S phase and an increase in the cell population at G1 phase occurred in a dose-dependent manner. In addition, Chidamide induced apoptosis and up-regulated p21 mRNA expression. These results suggest that Chidamide may arrest the cell cycle and inhibit the growth of hepatocellular carcinoma cells through up-regulation of p21. Further studies are required to clarify the antitumor activity of Chidamide in vivo and its mechanism in anticancer therapy.

Dysregulation of apoptosis is a pilot event before cancer development and plays important roles for cancer to develop resistance to chemical therapeutics. So exploring strategies to recovery the apoptosis balance is a charming and long-endeavored aim in the attempts to conquer cancers. The present study shows an exciting potency of a fusion peptide to inhibit and target to cancer cells, which is composed of BH3 (Bcl-2 Homology 3) effector domain from PUMA (p53 upregulated modulator of apoptosis) and targeting domain of trans-activator of transcription (TAT) and DV3. The in vitro results demonstrated cancer growth inhibition by the fusion peptide in colon cancer cells, as well as in lung adenocarcinoma cell line and breast carcinoma cell line of human origin. But the viability of HEK293, a noncancerous cell line, was not affected, indicating the cancer specificity of the fusion peptide. Apoptosis activation was induced by the peptide through the mitochondria pathway. In vivo studies displayed its tumor inhibiting ability by intratumoral injection. When the fusion peptide was administered systematically by tail vein, the peptide targeted the established tumors in nude mice. No other organs were significantly involved. The fusion peptide is an artificially designed molecule worthy of further evaluation and development.

Arsenic trioxide (As2O3) induces apoptosis in certain types of cancer cells. But the detailed mechanisms of As2O3 efficacy are not completely known. Here we demonstrate that As2O3 has a therapeutic effect on cervical cancer in vitro and in vivo. We investigated the As2O3-induced apoptosis in various cervical cancer cells. The apoptosis was triggered by mitochondrial pathway and associated with dissociation of Bcl-2 from Bax and VDAC, then the release of cytochrome c from Bax and VDAC channel, resulting in the activation of caspase-9 and caspase-3. The overexpression of Bcl-2 counteracted the As2O3-mediated apoptosis. The As2O3 treatment also resulted in an increased M phase cell cycle distribution by inducing microtubule polymerization. Two independent death-signaling pathways in cervical cancer cells were activated, one dominated by JNK/p38/GADD45 and one by p53 signals. Further investigation involving assessment of As2O3 on tumor cell growth in mice indicated that As203 also inhibited in vivo tumor growth. As2O3 as an inhibitor of cervical cancer proliferation both in vitro and in vivo suggests a potential clinical application in cervical cancer therapies.

Esophageal cancer is one of the most lethal human tumors, characterized by relative chemoresistance and poor prognosis. Researchers have been seeking for multimodality to improve its outcome of therapy. PUMA (p53 upregulated modulator of apoptosis) is a potent proapoptotic molecule that is rapidly induced in cells following DNA damage and is required for p53-induced apoptosis. We evaluated the therapeutic potential of PUMA adenovirus against esophageal cancer cell lines (KYSE-150, KYSE-410, KYSE-510 and YES-2). Infection with Ad-PUMA (PUMA Adenovirus) resulted in the more powerful cytotoxicity in these cell lines compared with Ad-p53. Furthermore, we assessed the efficacy of a combined treatment with Ad-PUMA and anticancer drug (cisplatin, paclitaxel, 5-fluorouracil, respectively) for these cells and found PUMA significantly increased the chemosensitivity of esophageal cancer cells, which may result from more abundant apoptosis induction. Interestingly, Ad-PUMA was found to be more efficient than Ad-p53 in inhibiting cell growth and enhancing the chemosensitivity of esophageal cancer cell lines irrespective of the p53 status. These results suggest that Ad-PUMA is a potent cytotoxic agent and could be a promising alternative in the cancer gene therapy in combination with chemotherapeutic agents.

Background: Breast cancer (BC) metastasis is the leading cause of poor prognosis and therapeutic failure. However, the mechanisms underlying cancer metastasis are far from clear. Methods: We screened candidate genes related to metastasis through genome-wide CRISPR screening and high-throughput sequencing of patients with metastatic BC, followed by a panel of metastatic model assays. The effects of tetratricopeptide repeat domain 17 (TTC17) on migration, invasion, and colony formation ability together with the responses to anticancer drugs were investigated in vitro and in vivo. The mechanism mediated by TTC17 was determined by RNA sequencing, Western blotting, immunohistochemistry, and immunofluorescence. The clinical significance of TTC17 was evaluated using BC tissue samples combined with clinicopathological data. Results: We identified the loss of TTC17 as a metastasis driver in BC, and its expression was negatively correlated with malignancy and positively correlated with patient prognosis. TTC17 loss in BC cells promoted their migration, invasion, and colony formation capacity in vitro and lung metastasis in vivo. Conversely, overexpressing TTC17 suppressed these aggressive phenotypes. Mechanistically, TTC17 knockdown in BC cells resulted in the activation of the RAP1/CDC42 pathway along with a disordered cytoskeleton in BC cells, and pharmacological blockade of CDC42 abolished the potentiation of motility and invasiveness caused by TTC17 silencing. Research on BC specimens demonstrated reduced TTC17 and increased CDC42 in metastatic tumors and lymph nodes, and low TTC17 expression was linked to more aggressive clinicopathologic characteristics. Through screening the anticancer drug library, the CDC42 inhibitor rapamycin and the microtubule-stabilizing drug paclitaxel showed stronger inhibition of TTC17-silenced BC cells, which was confirmed by more favorable efficacy in BC patients and tumor-bearing mice receiving rapamycin or paclitaxel in the TTC17Low arm. Conclusions: TTC17 loss is a novel factor promoting BC metastasis, that enhances migration and invasion by activating RAP1/CDC42 signaling and sensitizes BC to rapamycin and paclitaxel, which may improve stratified treatment strategies under the concept of molecular phenotyping-based precision therapy of BC. [ABSTRACT FROM AUTHOR]