p53, HER2 and tumor cell apoptosis correlate with clinical outcome after neoadjuvant bevacizumab plus chemotherapy in breast cancer

DNA damage, demethylation and anticancer activity of DNA methyltransferase (DNMT) inhibitors

Role of DNA damage and demethylation on anticancer activity of DNA methyltransferase inhibitors (DNMTi) remains undefined. We report the effects of DNMT1 gene deletion/disruption (DNMT1-/-) on anticancer activity of a class of DNMTi in vitro, in vivo and in human cancers. The gene deletion markedly attenuated cytotoxicity and growth inhibition mediated by decitabine, azacitidine and 5-aza-4'-thio-2'-deoxycytidine (aza-T-dCyd) in colon and breast cancer cells. The drugs induced DNA damage that concurred with DNMT1 inhibition, subsequent G2/M cell-cycle arrest and apoptosis, and upregulated p21 in DNMT1+/+ versus DNMT1-/- status, with aza-T-dCyd the most potent. Tumor growth and DNMT1 were significantly inhibited, and p21 was upmodulated in mice bearing HCT116 DNMT1+/+ xenograft and bladder PDX tumors. DNMT1 gene deletion occurred in ~ 9% human colon cancers and other cancer types at varying degrees. Decitabine and azacitidine demethylated CDKN2A/CDKN2B genes in DNMT1+/+ and DNMT1-/- conditions and increased histone-H3 acetylation with re-expression of p16INK4A/p15INK4B in DNMT1-/- state. Thus, DNMT1 deletion confers resistance to DNMTi, and their anti-cancer activity is determined by DNA damage effects. Patients with DNMT1 gene deletions may not respond to DNMTi treatment.

TP53 mutation-associated immune infiltration and a novel risk score model in HNSCC

In HNSCC, few studies have focused on the relationship between wild-type TP53 and mutant TP53-related immunity and prognosis. Our objective was to explore how TP53 mutation regulates the immunophenotype of HNSCC and thus affects the prognosis of HNSCC. Cox and Lasso regression were used to establish a prognostic model of TP53-related immune genes, on which basis a nomogram was used to establish a clinical prediction model, and ROC curves were further used to evaluate the effectiveness of the model. The risk of death in the TP53_WT group was only 0.68 times that in the TP53_Mut group (HR = 0.68, CI: 0.5–0.91, P < 0.05). T cells, CD8 T cells, cytotoxic lymphocytes, B lineage, NK cells, myeloid dendritic cells, and fibroblasts were significantly different between the TP53_Mut and TP53_WT groups (all P < 0.05). Time - dependent ROC curves of nomogram were plotted for 1-, 3-, and 5-year survival to further verify the predictive power of the nomogram for prognosis, and the AUCs were 0.78, 0.82, and 0.83, respectively. We showed there are significant differences in the immune microenvironment associated with wild-type TP53 and mutant TP53. The immune model associated with TP53 mutation has a good prediction ability for the prognosis of HNSCC and may be of reference value for other tumors with high mutation rate of TP53. Notably, the effect of TP53 mutation on the prognosis of HNSCC could be illustrated from an immunologic perspective.

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The differences in the immune microenvironment associated with wild-type TP53 and mutant TP53, affect the patient's sensitivity to immunotherapy.

TET2 and DNMT3A mutations and exceptional response to 4'-thio-2'-deoxycytidine in human solid tumor models

Background

Challenges remain on the selection of patients who potentially respond to a class of drugs that target epigenetics for cancer treatment. This study aims to investigate TET2/DNMT3A mutations and antitumor activity of a novel epigenetic agent in multiple human cancer cell lines and animal models.

Methods

Seventeen cancer cell lines and multiple xenograft models bearing representative human solid tumors were subjected to 4′-thio-2′-deoxycytidine (T-dCyd) or control treatment. Gene mutations in cell lines were examined by whole exome and/or Sanger sequencing. Specific gene expression was measured in cells and xenograft tumor samples by Western blotting and immunohistochemistry. TET2/DNMT3A mutation status in 47,571 human tumor samples was analyzed at cBioPortal for Cancer Genomics.

Results

Cell survival was significantly inhibited by T-dCyd in breast BT549, lung NCI-H23, melanoma SKMEL5 and renal ACHN cancer lines harboring deleterious TET2 and nonsynonymous DNMT3A mutations compared to 13 lines without such mutation pattern (P = 0.007). The treatment upregulated p21 and induced cell cycle arrest in NCI-H23 cells, and dramatically inhibited their xenograft tumor growth versus wildtype models. T-dCyd administrations led to a significant p21 increase and near eradication of tumor cells in the double-mutant xenografts by histological evaluation. TET2/DNMT3A was co-mutated in human lung, breast, skin and kidney cancers and frequently in angioimmunoblastic and peripheral T cell lymphomas and several types of leukemia.

Conclusions

Cell and animal models with concurrent mutations in TET2 and DNMT3A were sensitive to T-dCyd treatment. The mutations were detectable in human solid tumors and frequently occur in some hematological malignancies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13045-021-01091-5.

Association of Independent Prognostic Factors and Treatment Modality With Survival and Recurrence Outcomes in Breast Cancer

Importance

It is not well understood whether prognostic factors in breast cancer are affected by specific treatment and vary by clinical outcome type compared with untreated patients.

Objective

To identify independent clinical and molecular measurements associated with overall survival (OS) and recurrence-free survival (RFS) by homogeneous treatment in women with breast cancer.

Design, Setting, and Participants

This prognostic study included 956 patients diagnosed with invasive breast cancer from hospital centers across 4 geographical regions of the United States who participated in the accreditation program of the Commission on Cancer of the American College of Surgeons from 1985 to 1997. The duration of follow-up ranged from 1 to 282 months. The study analysis was conducted from June 10, 2019, to March 18, 2020.

Main Outcomes and Measures

Analysis of OS and RFS in patients who underwent chemotherapy, radiotherapy, or endocrine therapy alone compared with no systemic or locoregional therapy. Cox proportional hazards regression models were used to estimate independent performance and 95% CI of age, tumor size, number of positive nodes (nodal status), tumor grades 2 and 3, p53 status, estrogen receptor (ER) status, and ERBB2 (formerly HER2) status.

Results

Among 956 participants, median age was 61 (range, 25-96) years. Age (adjusted hazard ratio [AHR], 2.24; 95% CI, 1.27-3.94; P = .01) and high grade (AHR, 2.05; 95% CI, 1.09-3.86; P = .02), in addition to nodal status and tumor size, were independently associated with OS and RFS, respectively, in untreated patients. p53 status (AHR, 2.11; 95% CI, 1.07-4.18; P = .03) and ER status (AHR, 0.46; 95% CI, 0.23-0.92; P = .03) were associated with higher and lower risks of death, respectively, whereas nodal status (AHR, 1.13; 95% CI, 1.06-1.20; P < .005), high grade (AHR, 4.01; 95% CI, 1.51-10.70; P = .01), and ERBB2 positivity (AHR, 2.67; 95% CI, 1.25-5.70; P = .01) were associated with the risk of recurrence after endocrine therapy. Tumor size (AHR for OS, 2.76 [95% CI, 1.79-4.31; P < .005]; AHR for RFS, 2.27 [95% CI, 1.23-4.18; P = .01]) and ERBB2 status (AHR for OS, 5.35 [95% CI, 1.31-21.98; P = .02]; AHR for RFS, 6.05 [95% CI, 1.48-24.78; P = .01]) were independently associated with radiotherapy outcomes, and nodal status was significantly associated with chemotherapy outcomes (AHR for OS, 1.06 [95% CI, 1.02-1.09; P < .005]; AHR for RFS, 1.05 [95% CI, 1.01-1.09; P = .01]).

Conclusions and Relevance

In this study, independent prognostic factors were associated with specific treatment and weighted by the outcome category with reference to untreated patients within biological and clinical contexts.

Emodin promotes the arrest of human lymphoma Raji cell proliferation through the UHRF1‑DNMT3A‑∆Np73 pathways

Emodin is an active constituent found in the roots and rhizomes of numerous Chinese medicinal herbs. It exerts antitumor activity against Dalton's lymphoma in vivo, although the detailed mechanisms by which emodin induces apoptosis remains to be elucidated. The present study aimed to analyze the mechanisms underlying the response to emodin treatment. Using lymphoma Raji cells, an emodin‑induced cell proliferating inhibition model was first established, then flow cytometry, western blotting, reverse transcription‑quantitative polymerase chain reaction and luciferase reporter assay were performed. It was found that emodin decreased the percentage of Raji cell viability, induced apoptosis, and increased the activation of caspase 3, caspase 9 and poly (ADP‑ribose) polymerase through the downregulation of ubiquitin‑like protein containing PHD and RING domains 1 (UHRF1). The emodin‑induced downregulation of UHRF1 led to an increase in the level of DNA methyltransferase 3A, which in turn inhibited the activity of p73 promoter 2 and decreased the levels of NH2‑terminally truncated dominant‑negative p73. The treatment of Raji cells with emodin combined with doxorubicin led increased cell death of Raji cells, indicating that emodin may sensitize Raji cells to doxorubicin‑induced apoptosis.

Inhibition of Growth and Metastasis of Tumor in Nude Mice after Intraperitoneal Injection of Bevacizumab

Objective

To explore the inhibitory effect of bevacizumab, a vascular endothelial growth factor antibody, on angiogenesis in human osteosarcoma of nude mice.

Methods

Twenty‐one nude mice were inoculated with red fluorescent protein (RFP)‐labeled human osteosarcoma cell line 143B‐RFP, that is, clones that expressed RFP in the cytoplasm, and randomly assigned to one of three groups: G1 (Control group, injected with saline solution); G2 (intraperitoneal bevacizumab 2 mg/kg twice per week) and G3 (intraperitoneal bevacizumab 5 mg/kg, twice per week). The tumor‐bearing mice were examined in a fluorescence light box that was illuminated periodically. The primary tumors were measured by fluorescence imaging weekly and their volumes calculated.

Results

The mean tumor volumes were significantly smaller in the G3 (186.4 ± 100.8 mm³) than the control group (587.0 ± 406.8 mm³) (P < 0.05) on Day 31, and again significantly smaller in the G3 (677.3 ± 461.9 mm³) than the control group (3162.6 ± 1529.2 mm³) on Day 38 (P < 0.01). The average tumor volume in the G2 group was 493.5 ± 425.4 mm³ on Day 31 and 1870.1 ± 1524.8 mm³ on Day 38. The effect on tumor volume was greater in the G3 than the G2 group. Three mice in the G2 group, four in the G3 group and four in the control group developed lung metastases that were confirmed by pathological examination; these differences were not statistically significant (P < 0.05).

Conclusions

Bevacizumab exhibits strong antiangiogenesis activity in experimental osteosarcoma in a nude mouse model but does not influence the incidence of lung metastasis. Our findings may have considerable potential for the treatment of osteosarcoma.

High pKDR immunohistochemical expression is an unfavourable prognostic biomarker in patients with advanced colorectal cancer treated with chemotherapy plus bevacizumab

PURPOSE

To analyse the prognostic role of the immunohistochemical expression of pKDR in patients with advanced colorectal cancer treated with oxaliplatin and fluoropyrimidines combination chemotherapy with or without bevacizumab.

METHODS

Retrospective multicentre study, carried out at four hospitals in the Valencian Community (Spain). Patients evolution was compared based on the immunohistochemical expression of pKDR, classified using 4 categories: 0 (undetectable), 1 (mild), 2 (moderate) and 3 (high intensity). Patients were divided into two groups for the analysis: group 1 with low expression (0-1) vs. group 2 with high expression (2-3).

RESULTS

Histological samples for the pKDR analysis were available for 84 of the 112 patients selected. Seven (8.3 %) had undetectable or mild expression of pKDR (Group 1) and 77 (91.7 %) showed moderate or high expression of pKDR (Group 2). Response rate in Group 1 was 100 % compared to 54.2 % in Group 2 (p = 0.019). Progression-free survival (PFS) (15 vs. 12 months, p = 0.4) and overall survival (OS) (28 vs. 22 months, p = 0.09) were numerically but not significantly higher in patients from Group 1 vs. Group 2. Patients from Group 2 who received bevacizumab presented a significantly higher PFS (13 vs. 11, p = 0.015) and a numerically higher OS (23 vs. 17 months, p = 0.27) than those treated exclusively with chemotherapy.

CONCLUSIONS

Our results suggest that the absence or low expression of pKDR is associated with a better prognostic profile in patients with advanced colorectal cancer treated with chemotherapy and bevacizumab. Patients with a high pKDR expression benefit from the combination of chemotherapy with bevacizumab.

The significance of combining VEGFA, FLT1, and KDR expressions in colon cancer patient prognosis and predicting response to bevacizumab

Targeting angiogenesis through inhibition of the vascular endothelial growth factor (VEGF) pathway has been successful in the treatment of late stage colorectal cancer. However, not all patients benefit from inhibition of VEGF. Ras status is a powerful biomarker for response to anti-epidermal growth factor receptor therapy; however, an appropriate biomarker for response to anti-VEGF therapy is yet to be identified. VEGF and its receptors, FLT1 and KDR, play a crucial role in colon cancer progression; individually, these factors have been shown to be prognostic in colon cancer; however, expression of none of these factors alone was predictive of tumor response to anti-VEGF therapy. In the present study, we analyzed the expression levels of VEGFA, FLT1, and KDR in two independent colon cancer datasets and found that high expression levels of all three factors afforded a very poor prognosis. The observation was further confirmed in another independent colon cancer dataset, wherein high levels of expression of this three-gene signature was predictive of poor prognosis in patients with proficient mismatch repair a wild-type KRas status, or mutant p53 status. Most importantly, this signature also predicted tumor response to bevacizumab, an antibody targeting VEGFA, in a cohort of bevacizumab-treated patients. Since bevacizumab has been proven to be an important drug in the treatment of advanced stage colon cancer, our results suggest that the three-gene signature approach is valuable in terms of its prognostic value, and that it should be further evaluated in a prospective clinical trial to investigate its predictive value to anti-VEGF treatment.

Chemotherapy mediates intestinal injury via p53/p53 upregulated modulator of apoptosis (PUMA) signaling pathway

OBJECTIVE

The aim of this study was to investigate the potential mechanism and signaling pathway involved in chemotherapy-induced intestinal mucosal injury (CIMI), which is a common physiopathological problem in patients with cancer.

METHODS

For the in vivo experiment, mice received intraperitoneal injection of 5-fluorouracil (5-FU) at a dose of 75 mg/kg/day for 1, 3 or 5 days. Villus height and crypt depth of the small intestine, cell apoptosis and proliferation were then examined to determine the extent of CIMI. The expressions of Akt, p53, PUMA and p21 were evaluated both in vivo in mice models and in vitro in the IEC-6 and HCT116 cell lines.

RESULTS

After 5-FU therapy both the intestinal villus height (275.93 μm vs 164.52 μm, P < 0.001) and crypt depth (64.13 μm vs 42.48 μm, P < 0.001) were decreased. The apoptotic index was greatly increased from 0.32% to 15.84% (P < 0.001) and proliferation was suppressed (63.58% vs 39.15%, P < 0.001). Additionally, p53 expression was significantly increased in the intestinal crypt along with the expressions of PUMA and p21. Western blot showed that the administration of 5-FU induced p53/PUMA-mediated apoptosis and upregulated p21 expression to suppress cell proliferation.

CONCLUSION

Chemotherapy might mediate intestinal injury via p53/PUMA-mediated apoptotic signaling and the suppression of proliferation in response to p21.

Small activating RNA restores the activity of the tumor suppressor HIC-1 on breast cancer

HIC-1 is a gene that is hypermethylated in cancer, and commonly downregulated in human breast cancer. However, the precise mechanisms and molecular pathways regulated by HIC-1 remain unclear. We assessed HIC-1 expression on a tissue microarray containing 80 cases of breast cancer. We also analyzed its biological function by restoring HIC-1 expression using 5-aza-2′ deoxycytidine (5-CdR) and small-activating RNAs for the reversal of HIC-1 tumor suppressive effects on MCF-7 and MDA-MB-231 cell lines. An Agilent Q44h global expressing microarray was probed after restoring the expression of HIC-1. Data demonstrated that HIC-1 expression was reduced significantly in breast cancer tissues. HIC-1 immunohistochemistry resulted in mean staining scores in cancer tissue and normal ductal epithelia of 3.54 and 8.2, respectively (p<0.01). 5-CdR partially reversed HIC-1 expression, and modulated cell growth and apoptosis. dsHIC1-2998, an saRNA, showed activating efficacy in breast cancer cells. A group of differentially expressed genes were characterized by cDNA microarray. Upon saRNA treatment, genes upregulated included those involved in immune activation, cell cycle interference, the induction of apoptosis, anti-metastasis, and cell differentiation. Downregulated genes included oncogenes and those that play roles in cell invasion, cell growth, and cell division. Our findings may provide valuable resources not only for gene functional studies, but also for potential clinical applications to develop novel drug targets.

Controlling escape from angiogenesis inhibitors

Selective inhibition of vascular endothelial growth factor (VEGF) increases the efficacy of chemotherapy and has beneficial effects on multiple advanced cancers, but response is often limited and the disease eventually progresses. Changes in the tumour microenvironment--hypoxia among them--that result from vascular pruning, suppressed angiogenesis and other consequences of VEGF inhibition can promote escape and tumour progression. New therapeutic approaches that target pathways that are involved in the escape mechanisms add the benefits of blocking tumour progression to those of slowing tumour growth by inhibiting angiogenesis.

Tumor stromal vascular endothelial growth factor A is predictive of poor outcome in inflammatory breast cancer

Background

Inflammatory breast cancer (IBC) is a highly angiogenic disease; thus, antiangiogenic therapy should result in a clinical response. However, clinical trials have demonstrated only modest responses, and the reasons for these outcomes remain unknown. Therefore, the purpose of this retrospective study was to determine the prognostic value of protein levels of vascular endothelial growth factor (VEGF-A), one of the main targets of antiangiogenic therapy, and its receptors (VEGF-R1 and -R2) in IBC tumor specimens.

Patients and Methods

Specimens from IBC and normal breast tissues were obtained from Algerian patients. Tumor epithelial and stromal staining of VEGF-A, VEGF-R1, and VEGF-R2 was evaluated by immunohistochemical analysis in tumors and normal breast tissues; this expression was correlated with clinicopathological variables and breast cancer-specific survival (BCSS) and disease-free survival (DFS) duration.

Results

From a set of 117 IBC samples, we evaluated 103 ductal IBC tissues and 25 normal specimens. Significantly lower epithelial VEGF-A immunostaining was found in IBC tumor cells than in normal breast tissues (P <0.01), cytoplasmic VEGF-R1 and nuclear VEGF-R2 levels were slightly higher, and cytoplasmic VEGF-R2 levels were significantly higher (P = 0.04). Sixty-two percent of IBC tumors had high stromal VEGF-A expression. In univariate analysis, stromal VEGF-A levels predicted BCSS and DFS in IBC patients with estrogen receptor-positive (P <0.01 for both), progesterone receptor-positive (P = 0.04 and P = 0.03), HER2+ (P = 0.04 and P = 0.03), and lymph node involvement (P <0.01 for both). Strikingly, in a multivariate analysis, tumor stromal VEGF-A was identified as an independent predictor of poor BCSS (hazard ratio [HR]: 5.0; 95% CI: 2.0-12.3; P <0.01) and DFS (HR: 4.2; 95% CI: 1.7-10.3; P <0.01).

Conclusions

To our knowledge, this is the first study to demonstrate that tumor stromal VEGF-A expression is a valuable prognostic indicator of BCSS and DFS at diagnosis and can therefore be used to stratify IBC patients into low-risk and high-risk groups for death and relapses. High levels of tumor stromal VEGF-A may be useful for identifying IBC patients who will benefit from anti-angiogenic treatment.