Aldehyde Dehydrogenase 1 Expression Predicts Chemoresistance and Poor Clinical Outcomes in Patients with Locally Advanced Cervical Cancer Treated with Neoadjuvant Chemotherapy Prior to Radical Hysterectomy

Effect of ALDH1A1 and CD44 on Survival and Disease Recurrence in Patients With Osteosarcoma

PURPOSE

Emerging evidence suggests that osteosarcoma stem cells (OSCs) may be responsible for tumor initiation propagation, recurrence, and resistance to therapy. We set out to evaluate the relationship between the abundance of ALDH1A1 and CD44-positive cells in biopsy and resection samples on disease recurrence and overall survival.

METHODS

A retrospective review of 20 patients, including biopsy and resection samples, was performed at a comprehensive cancer center. Additionally, we queried the publicly available TARGET dataset of osteosarcoma patients.

RESULTS

Neither the percentages of ALDH1A1-positive cells nor CD44-positive cells were significantly associated with overall mortality or disease recurrence in either biopsy or resection samples. Unlike our institutional data, overall survival was significantly correlated to higher ALDH1A1 expression in the TARGET dataset both in univariate and age-adjusted analyses.

CONCLUSIONS

ADLH1 and CD44, potential markers of OSCs, were not found to be reliable clinical immunohistochemical prognostic markers for osteosarcoma patient survival, specifically disease-free survival. Osteosarcoma patients with high ALDH1A1 RNA expression showed improved overall survival in examining a national genomic database of osteosarcoma patients but again no association with disease-free survival. The potential of CD44 and ALDH1A1 as cellular-specific prognostic markers of survival, and as possible molecular targets, may be limited in osteosarcoma.

Regulation of the aryl hydrocarbon receptor in cancer and cancer stem cells of gynecological malignancies: An update on signaling pathways

Gynecological malignancies are a female type of cancers that affects the reproductive system. Cancer metastasis or recurrence mediated by cellular invasiveness occurs at advanced stages of cancer progression. Cancer Stem Cells (CSCs) enrichment in tumors leads to chemoresistance, which results in cancer mortality. Exposure to environmental pollutants such as polycyclic aromatic hydrocarbons is associated with an increased the risk of CSC enrichment in gynecological cancers. One of the important pathways that mediates the metabolism and bioactivation of these environmental chemicals is the transcription factor, aryl hydrocarbon receptor (AhR). The present review explores the molecular mechanisms regulating the crosstalk and interaction of the AhR with cancer-related signaling pathways, such as apoptosis, epithelial-mesenchymal transition, immune checkpoints, and G-protein-coupled receptors in several gynecological malignancies such as ovarian, uterine, endometrial, and cervical cancers. The review also discusses the potential of targeting the AhR pathway as a novel chemotherapy for gynecological cancers.

Cancer Stem Cells and Their Possible Implications in Cervical Cancer: A Short Review

Cervical cancer (CC) is the fourth most common type of gynecological malignancy affecting females worldwide. Most CC cases are linked to infection with high-risk human papillomaviruses (HPV). There has been a significant decrease in the incidence and death rate of CC due to effective cervical Pap smear screening and administration of vaccines. However, this is not equally available throughout different societies. The prognosis of patients with advanced or recurrent CC is particularly poor, with a one-year relative survival rate of a maximum of 20%. Increasing evidence suggests that cancer stem cells (CSCs) may play an important role in CC tumorigenesis, metastasis, relapse, and chemo/radio-resistance, thus representing potential targets for a better therapeutic outcome. CSCs are a small subpopulation of tumor cells with self-renewing ability, which can differentiate into heterogeneous tumor cell types, thus creating a progeny of cells constituting the bulk of tumors. Since cervical CSCs (CCSC) are difficult to identify, this has led to the search for different markers (e.g., ABCG2, ITGA6 (CD49f), PROM1 (CD133), KRT17 (CK17), MSI1, POU5F1 (OCT4), and SOX2). Promising therapeutic strategies targeting CSC-signaling pathways and the CSC niche are currently under development. Here, we provide an overview of CC and CCSCs, describing the phenotypes of CCSCs and the potential of targeting CCSCs in the management of CC.

Phytocompounds from the medicinal and dietary plants: Multi-target agents for cancer prevention and therapy

Cervical cancer is the fourth leading cause of cancer death among women worldwide. Due to cervical cancer's high incidence and mortality, there is an unmet demand for effective diagnostic, therapeutic, and preventive agents. At present, the preferred treatment strategies for advanced metastatic cervical cancer include surgery, radiotherapy, and chemotherapy. However, cervical cancer is gradually developing resistance to chemotherapy, thereby reducing its efficacy. Over the last several decades, phytochemicals, a general term for compounds produced from plants, have gained attention for their role in preventing cervical cancer. This role in cervical cancer prevention has garnered attention on the medicinal properties of fruits and vegetables. Phytochemicals are currently being evaluated for their ability to block proteins involved in carcinogenesis and chemoresistance against cervical cancer. Chemoresistance to cancer drugs like cisplatin, doxorubicin, and 5-fluorouracil has become a significant limitation of drug-based chemotherapy. However, the combination of cisplatin with other phytochemicals has been identified as a promising alternative to subjugate cisplatin resistance. Phytochemicals are promising chemo-preventive and chemotherapeutic agents as they possess antioxidant, anti-inflammatory, and anti-proliferative potential against many cancers, including cervical cancer. Furthermore, the ability of the phytochemicals to modulate cellular signaling pathways through up and down regulation of various proteins has been claimed for their therapeutic potential. Phytochemicals also display a wide range of biological functions, including cell cycle arrest, apoptosis induction, inhibition of invasion, and migration in cervical cancer cells. Numerous studies have revealed the critical role of different signaling proteins and their signaling pathways in the pathogenesis of cervical cancer. Here, we review the ability of several dietary phytochemicals to alter carcinogenesis by modulating various molecular targets.

Changes in Stem Cell Regulation and Epithelial Organisation during Carcinogenesis and Disease Progression in Gynaecological Malignancies

Simple Summary

Recent advances in our understanding of the stem cell potential in adult tissues have far-reaching implications for cancer research, and this creates new opportunities for the development of new therapeutic strategies. Here we outline changes in stem cell biology that characterize main gynaecological malignancies, ovarian, endometrial, and cervical cancer, and focus on specific differences between them. We highlight the importance of the local niche environment as a driver of malignant transformation in addition to mutations in key cancer-driving genes. Patient-derived organoids capture in vitro main aspects of cancer tissue architecture and stemness regulatory mechanisms, thus providing a valuable new platform for a personalized approach in the treatment of gynecological malignancies. This review summarizes the main achievement and formulates remaining open questions in this fast-evolving research field.

Abstract

Gynaecological malignancies represent a heterogeneous group of neoplasms with vastly different aetiology, risk factors, molecular drivers, and disease outcomes. From HPV-driven cervical cancer where early screening and molecular diagnostics efficiently reduced the number of advanced-stage diagnosis, prevalent and relatively well-treated endometrial cancers, to highly aggressive and mostly lethal high-grade serous ovarian cancer, malignancies of the female genital tract have unique presentations and distinct cell biology features. Recent discoveries of stem cell regulatory mechanisms, development of organoid cultures, and NGS analysis have provided valuable insights into the basic biology of these cancers that could help advance new-targeted therapeutic approaches. This review revisits new findings on stemness and differentiation, considering main challenges and open questions. We focus on the role of stem cell niche and tumour microenvironment in early and metastatic stages of the disease progression and highlight the potential of patient-derived organoid models to study key events in tumour evolution, the appearance of resistance mechanisms, and as screening tools to enable personalisation of drug treatments.

A Novel Targeted Therapy System for Cervical Cancer: Co-Delivery System of Antisense LncRNA of MDC1 and Oxaliplatin Magnetic Thermosensitive Cationic Liposome Drug Carrier

BACKGROUND

This study was aimed to prepare a novel magnetic thermosensitive cationic liposome drug carrier for the codelivery of Oxaliplatin (OXA) and antisense lncRNA of MDC1 (MDC1-AS) to Cervical cancer cells and evaluate the efficiency of this drug carrier and its antitumor effects on Cervical cancer.

METHODS

Thermosensitive magnetic cationic liposomes were prepared using thin-film hydration method. The OXA and MDC1-AS vectors were loaded into the codelivery system, and the in vitro OXA thermosensitive release activity, efficiency of MDC1-AS regulating MDC1, in vitro cytotoxicity, and in vivo antitumor activity were determined.

RESULTS

The codelivery system had desirable targeted delivery efficacy, OXA thermosensitive release, and MDC1-AS regulating MDC1. Codelivery of OXA and MDC1-AS enhanced the inhibition of cervical cancer cell growth in vitro and in vivo, compared with single drug delivery.

CONCLUSION

The novel codelivery of OXA and MDC1-AS magnetic thermosensitive cationic liposome drug carrier can be applied in the combined chemotherapy and gene therapy for cervical cancer.

The Effect of Neoadjuvant Chemotherapy on Lymph Node Metastasis of FIGO Stage IB1-IIB Cervical Cancer: A Systematic Review and Meta-Analysis

Objectives

This study aimed to assess the effect of neoadjuvant chemotherapy (NACT) on the rate of lymph node metastasis (LNM) in FIGO stage IB1-IIB cervical cancer patients and compare the LNM between NACT plus surgery and surgery only.

Methods

We identified 34 eligible studies in PubMed, Web of Science, Cochrane Library, and EMBASE from inception to July 27, 2019. Data analyses were performed by Stata (version 13) and Revman (version 5.3).

Results

In these 34 included studies, the pooled incidence of LNM was estimated as 23% (95% CI, 0.20-0.26; I² = 79.6%, P<0.001). In the subgroup analysis, we identified five factors, including study type, year of publication, continents from which patients came, histological type and the FIGO stage. When taking FIGO stage into consideration, the LNM rate was 13% in stage IB (95% CI: 0.10-0.15; I² = 5.5%, P=0.385), 23% in stage IIA (95% CI: 0.18-0.28; I² = 0%, P=0.622), and 27% in stage IIB (95% CI: 0.20-0.33; I² = 0%, P=0.898), respectively. Through the comparison between NACT plus surgery and surgery only based on the six randomized controlled trials, the incidence of positive lymph nodes was lower in patients receiving NACT plus surgery than surgery only (RR=0.57, 95% CI: 0.39-0.83; I² = 60.5%, P=0.027). The 5-year OS was higher in the NACT + surgery group than surgery-only group (RR=1.13, 95% CI: 1.03-1.23; I² = 0.0%, P=0.842).

Conclusions

Among cervical cancer in stage IB1-IIB, the preoperative NACT plus radical surgery resulted in a 23% probability of LNM, which was lower than those receiving radical surgery only. In stage IIA and IIB, the effect of NACT to reduce LNM was more obvious.

ALDH-1-positive cells exhibited a radioresistant phenotype that was enhanced with hypoxia in cervical cancer

BACKGROUND

We have previously found there was a small subpopulation of cells with cancer stem cell-like phenotype ALDH-1 in cervical cancer. Radiotherapy has been applied in most of the cervical cancer. However,the mechanisms underlying radioresistance still remained elusive. Our study is to explore whether ALDH+ cell promotes radioresistance by hypoxia.

METHODS

Cells were respectively cultured in hypoxia and normoxia environment and analyzed for marker stability, and cell cycle distribution.

RESULTS

Cell growth, apoptosis, cell cycle, sphere formation were affected by hypoxia. ALDH-1 and CHK2 were upregulated after hypoxia.

CONCLUSIONS

Here we show that ALDH-1 positive cells contribute to cervical carcinoma radioresistance through preferential activation of the DNA damage checkpoint response and an increase in DNA repair capacity. The fraction of these cells is enriched after radiation in cervical carcinoma.

Quantitative Changes in the Population of Cancer Stem Cells after Radiation Exposure in a Dose of 10 Gy as a Prognostic Marker of Immediate Results of the Treatment of Squamous Cell Cervical Cancer

Prognostic significance of the proportion of cancer stem cells in cervical scrapings from 38 patients with uterine cervical cancer before treatment and after irradiation in a total dose of 10 Gy was assessed for immediate results of radio- and combined chemoradiotherapy evaluated by the degree of tumor regression in 3-6 months after the treatment. Cancer stem cells were detected as cells with CD44+CD24low immunophenotype by flow cytometry. The proportion of cancer stem cells in patients with the complete tumor regression decreased by on average 2.2±1.1% after irradiation, while in patients with partial regression this indicator increased by on average 3.3±2.3% (p=0.03). Multiple regression analysis revealed two independent indicators affecting tumor regression: the stage of the disease (which is quite expected) and change in the proportion of cancer stem cells after the first irradiation sessions (R=0.60, p<0.002 for the model in the whole). The proportion of cancer stem cells before the treatment did not have prognostic significance.

Cervical cancer stem cell-associated genes: Prognostic implications in cervical cancer

Cervical cancer is the fourth most common type of gynecological malignancy to affect females, worldwide. Although high-risk human papillomavirus (HR-HPV) infection is the primary etiologic agent associated with the development of cervical cancer, cancer stem cells (CSCs) also serve a prominent role in the development, metastasis, recurrence and prognosis of the disease. CSCs are a small subpopulation of cells that have the ability to self-renew and are present in the majority of tumors, including cervical cancer. Studies describing the phenotype of cervical CSCs (CCSCs) vary in their definition of the expression pattern of principal biomarkers, including Musashi-1, aldehyde dehydrogenase 1, Oct3/4, Sox2 and CD49f. However, these markers are not observed in all cancers, although several may be present in multiple tumor types. The present review describes the potential biomarkers of CSCs in cervical cancer. These CCSC biomarkers may serve as molecular targets to enhance the efficacy and reduce the side effects associated with chemotherapeutic treatment in HR-HPV-positive cervical cancer.

Prognostic value of ALDH1 and Nestin in advanced cancer: a systematic meta-analysis with trial sequential analysis

Background

Novel prognostic markers and therapeutic targets for advanced cancer are urgently needed. This report with trial sequential analysis (TSA) was first conducted to provide robust estimates of the correlation between aldehyde dehydrogenase 1 (ALDH1) and Nestin and clinical outcomes of advanced cancer patients.

Methods

Hazard ratios (HRs) with 95% confidence intervals (CIs) were summarized for overall survival (OS), disease-free survival (DFS), progression-free survival (PFS), cancer-specific survival (CSS), relapse/recurrence-free survival (RFS), and metastasis-free survival (MFS) from multivariable analysis. TSA was performed to control for random errors.

Results

A total of 20 studies with 2050 patients (ALDH1: 15 studies with 1557 patients and Nestin: 5 studies with 493 patients) were identified. ALDH1 (HR = 2.28, p < 0.001) and Nestin (HR = 2.39, p < 0.001) were associated with a worse OS, as confirmed by TSA. Nestin positivity was linked to a poor PFS (HR = 2.08, p < 0.001), but ALDH1 was not linked to DFS, RFS, MFS, or PFS, and TSA showed that more studies were needed. Subgroup analysis by tumor type indicated that ALDH1 positivity may be associated with shorter OS in breast, head and neck cancers, but there was no association with colorectal cancer. Subgroup analysis by study source showed that ALDH1 positivity was correlated with a worse OS for Japanese (HR = 1.94, p = 0.002) and European patients (HR = 4.15, p < 0.001), but there was no association for Chinese patients. Subgroup analysis by survival rate showed that ALDH1 positivity correlated with poor OS at ⩾ 5 years (HR = 2.33, p < 0.001) or 10 years (HR = 1.76, p = 0.038).

Conclusions

ALDH1 may be more valuable as an effective therapeutic target than Nestin for improving the long-term survival rate of advanced cancer. Additional prospective clinical trials are needed across different cancer types.

Neoadjuvant Chemotherapy with Taxane and Platinum Followed by Radical Hysterectomy for Stage IB2-IIB Cervical Cancer: Impact of Histology Type on Survival

The current study examined the histology-specific impact of neoadjuvant chemotherapy (NACT) with a taxane/platinum regimen on survival in women with locally-advanced cervical cancer who underwent radical hysterectomy. This nation-wide retrospective cohort study examined women with clinical stage IB2-IIB cervical cancer who received NACT prior to radical hysterectomy from 2004–2008 (n = 684). NACT type (taxane/platinum versus others) was correlated with survival based on histology: 511 squamous versus 173 non-squamous. Taxane/platinum chemotherapy use was more common in non-squamous compared to squamous tumors (53.8% versus 20.7%, P < 0.001). In both histology types, the taxane/platinum regimen was more frequently utilized over time (both, P < 0.01). Among squamous tumors, women who received taxane/platinum chemotherapy had survival comparable to those who received other regimens: 5-year rates for disease-free survival, 69.0% versus 70.1%, P = 0.98; and cause-specific survival, 80.0% versus 81.0%, P = 0.93. Similarly, in non-squamous tumors, disease-free survival (5-year rates: 60.4% versus 59.0%, P = 0.86) and cause-specific survival (74.7% versus 76.3%, P = 0.70) were similar. In conclusion, use of taxane/platinum regimens for NACT significantly increased during the study period. Irrespective of histology type, in women with clinical stage IB2-IIB cervical cancer who underwent NACT prior to radical hysterectomy, taxane/platinum regimens had a similar effect on survival compared to non-taxane/platinum regimens.

Cancer Stem Cells from Tumor Cell Lines Activate the DNA Damage Response Pathway after Ionizing Radiation More Efficiently Than Noncancer Stem Cells

Recently, a subpopulation of tumor cells, called cancer stem cells (CSC), has been characterized, and these have emerged as a major topic in cancer research. CSC are proposed to repair DNA damage more efficiently than the rest of tumor cells, resisting chemotherapy or radiotherapy and causing clinical recurrence and metastasis. We aimed to determine the molecular basis of radioresistance and first compared the response to ionizing radiation (IR) between cancer stem cell-enriched cultures grown as spheres and conventional tumor cell line cultures grown as monolayer, from HeLa and MCF-7 cancer cell lines. To verify that our sphere cultures were enriched in CSC, we evaluated the double staining of CD49f and ALDH activity for HeLa cells by flow cytometry. We then evaluated whether differences could exist in sensor elements in the DNA damage response pathway among these cultures. We found that CSC cultures showed less sensitivity to radiation than conventional tumor cell line cultures. We observed a higher baseline expression of activated response sensor proteins of DNA damage, such as ATM, H2A.X, and PARP1, in untreated CSC cultures. These findings provide the first evidence, to our knowledge, that DNA damage response sensor proteins are present and preferentially activated in CSC, as opposed to the bulk of cells in monolayer cultures. Likewise, they provide the basis for biological differences in response to IR between CSC and other tumor cell populations. Understanding the DNA damage response pathway may provide therapeutic targets to sensitize CSC to cytotoxic therapies to improve current cancer treatments.

Upregulation of stem cell markers ALDH1A1 and OCT4 as potential biomarkers for the early detection of cervical carcinoma

Previous studies have reported the upregulation of stem cell biomarkers that are associated with tumorigenesis, in particular with cancer infiltration, recurrence and metastasis. Infection by human papilloma virus (HPV) is the main etiopathological factor of cervical carcinogenesis, but the expression of stem cell markers in cervical carcinoma and HPV infection have yet to be investigated so far. A total of 94 cases of fresh cervical tissues, 116 cases of paraffin-embedded cervical specimens and 72 cases of peripheral blood samples were collected from Uighur women who were either diagnosed with cervical squamous cell carcinoma (SCC) or cervical intraepithelial neoplasia (CIN) II-III, or from healthy subjects (negative controls, NC). HPV infection was detected in tissue DNA by polymerase chain reaction (PCR) with a HPV genotyping kit. The mRNA expression levels of aldehyde dehydrogenase 1 family member A1 (ALDH1A1), nanog homeobox (NANOG), POU class 5 homeobox 1 (OCT4), SRY-box 2 (SOX2) and twist family BHLH transcription factor 1 (Twist1) were determined using reverse transcription-quantitative PCR (RT-qPCR). Histological analysis was performed in order to examine the protein expression of ALDH1A1 and OCT4 in paraffin-embedded tissue specimens by immunohistochemical staining and the plasma levels of those two proteins was measured by ELISA. RT-qPCR analysis indicated a significant increase in the mRNA expression of ALDH1A1 and OCT4 in CIN II-III and SCC tissue specimens compared with NC (P<0.05). Although the expression levels of NANOG, SOX2 and Twist1 were significantly higher in SCC compared with NC (P<0.05), no significant difference was revealed in CIN II-III tissues compared with SCC or NC (P>0.05). Subsequent analysis by immunohistochemistry staining confirmed that the upregulation of ALDH1A1 and OCT4 was also significantly increased in SCC and CIN II-III compared with controls at the protein level. Notably, ELISA analysis detected significantly higher levels of ALDH1A1 and OCT4 in the peripheral blood (plasma) of patients with SCC compared with healthy subjects. The upregulation of stem cell markers ALDH1A1 and OCT4 in cervical carcinoma and its precursor lesions, in particular in the peripheral blood, indicates that ALDH1A1 and OCT4 may serve as biomarkers for the early detection of cervical carcinoma or for the monitoring of treatment of patients.

Acquired treatment response from neoadjuvant chemotherapy predicts a favorable prognosis for local advanced cervical cancer: A meta-analysis

BACKGROUND

Local advanced cervical cancer (LACC) is a considerable health crisis for women, and neoadjuvant chemotherapy (NACT) followed by radical surgery has been a suggested therapy method. However, the correlation between the tumor treatment response to NACT and the prognosis of LACC remains controversial.

METHODS

A comprehensive meta-analysis was performed to precisely assess the prognostic role of the clinical response and pathological response to NACT for LACC. The included studies were identified using PubMed and Web of Science up to July 2017. Hazard ratios (HR) and corresponding 95% confidence intervals (95% CI) for overall survival (OS) and disease-free survival (DFS) were determined using Review Manager (version 5.3) and Stata (version 12).

RESULTS

A total of 13 publications of 4727 cases were included. The treatment clinical response rate ranged from 58.49% to 86.54%, and the pathological response rate was 7.5% to 78.81%. Our combined results suggested that a clinical response was favorable for OS (HR=3.36, 95% CI: 2.41-4.69) and DFS (HR=2.36, 95% CI: 1.82-3.06). Further, a pathological response predicts favorable OS (HR=5.45, 95% CI: 3.42-8.70) and DFS (HR=3.61, 95% CI: 2.0-6.52).

CONCLUSION

The response to NACT, including the clinical and pathological response, was associated with a favorable prognosis for patients with LACC. However, the predictive value of this factor in clinical practice warrants further in-depth research.

TAK1 inhibitor 5Z-7-oxozeaenol sensitizes cervical cancer to doxorubicin-induced apoptosis

Aberrant activation of nuclear factor-κB (NF-κB) allows cancer cells to escape chemotherapy-induced cell death and acts as one of the major mechanisms of acquired chemoresistance in cervical cancer. TAK1, a crucial mediator that upregulates NF-κB activation in response to cellular genotoxic stress, is required for tumor cell viability and survival. Herein, we examined whether TAK1 inhibition is a potential therapeutic strategy for treating cervical cancer. We found that TAK1 inhibitor 5Z-7-oxozeaenol significantly augmented the cytotoxic effects of Dox in a panel of cervical cancer cell lines. Treatment with 5Z-7-oxozeaenol hindered Dox-induced NF-κB activation and promoted Dox-induced apoptosis in cervical cancer cells. Moreover, 5Z-7-oxozeaenol showed similar effects in both positive and negative human papillomavirus-infected cervical cancer cells. Taken together, our results provide evidence that TAK1 inhibition significantly sensitizes cervical cancer cells to chemotherapy-induced cell death and supports the use of TAK1 inhibitor with current chemotherapies in the clinic for patients with refractory cervical cancer.

The association between short-term response and long-term survival for cervical cancer patients undergoing neoadjuvant chemotherapy: a system review and meta-analysis

Controversy exists regarding whether a short-term response has an impact on the long-term survival of cervical cancer patients undergoing neoadjuvant chemotherapy (NACT). This study was designed to identify the predictive role of an early response by pooling the results of previous studies. The PubMed and Embase databases were searched through July 2016, and the associations between an early response and disease-free survival (DFS) were pooled by hazard ratio (HR) using random effects models. Six studies involving 490 cervical cancer patients, with 336 responders and 154 non-responders, were finally included in the meta-analysis. The HR for 1-year DFS between early responders and non-responders was 0.25 (95% CI 0.10-0.58, P = 0.001). The HRs for 2-, 3-, 4-, and 5-year DFS were 0.28 (95% CI 0.15-0.56), 0.27 (95% CI 0.16-0.45), 0.29 (95% CI 0.17-0.50) and 0.33 (95% CI 0.20-0.54), respectively. No obvious heterogeneity was found among the studies, with I² = 0, and a sensitivity analysis showed that all pooled results were robust with logHR confidence limits < 0. An early response was associated with DFS, and responders achieved a significantly higher survival rate than non-responders. This finding should be validated in future prospective studies.

Molecular markers of DNA damage and repair in cervical cancer patients treated with cisplatin neoadjuvant chemotherapy: an exploratory study

Neoadjuvant (or induction) chemotherapy can be used for cervical cancer patients with locally advanced disease; this treatment is followed by radical surgery and/or radiation therapy. Cisplatin is considered to be the most active platinum agent drug for this cancer, with a response rate of 20%. In order to understand how the cisplatin treatment affects the stress response, in this work, we performed an exploratory study to analyze a number of stress proteins before and after cisplatin neoadjuvant chemotherapy. The study involved 14 patients; the pre- and post-chemotherapy paired biopsies were examined by hematoxylin and eosin staining and by immunohistochemistry. The proteins evaluated were p53, P16/INK4A, MSH2, nuclear protein transcriptional regulator 1 (NUPR1), and HSPB1 (total: HSPB1/t and phosphorylated: HSPB1/p). These proteins were selected because there is previous evidence of their relationship with drug resistance. The formation of platinum-DNA adducts was also studied. There was a great variation in the expression levels of the mentioned proteins in the pre-chemotherapy biopsies. After chemotherapy, p53 was not significantly affected by cisplatin, as well as P16/INK4A and MSH2 while nuclear NUPR1 content tended to decrease (p = 0.056). Cytoplasmic HSPB1/t expression levels decreased significantly following cisplatin therapy while nuclear HSPB1/t and HSPB1/p tended to increase. Since the most significant changes following chemotherapy appeared in the HSPB1 expression levels, the changes were confirmed by Western blot. The platinum-DNA adducts were observed in HeLa cell in apoptosis; however, in the tumor samples, the platinum-DNA adducts were observed in morphologically healthy tumor cells; these cells displayed nuclear HSPB1/p. Further mechanistic studies should be performed to reveal how HSPB1/p is related with drug resistance. When the correlations of the markers with the response to neoadjuvant chemotherapy were examined, only high pre-chemotherapy levels of cytoplasmic HSPB1/p correlated with a poor clinical and pathological response to neoadjuvant cisplatin chemotherapy (p = 0.056) suggesting that this marker could be useful opening its study in a larger number of cases.

Overview of Cancer Stem Cells and Stemness for Community Oncologists

Advances in cancer research in the past have led to an evolving understanding of cancer pathogenesis and the development of novel drugs that significantly improve patient outcomes. However, many patients still encounter treatment resistance, recurrence, or metastasis and eventually die from progressing disease. Experimental evidence indicates that a subpopulation of cancer cells, called cancer stem cells (CSCs), possess "stemness" properties similar to normal stem cells, including self-renewal, differentiation, and proliferative potential. These stemness properties are lost during differentiation and are governed by pathways such as STAT3, NANOG, NOTCH, WNT, and HEDGEHOG, which are highly dysregulated in CSCs due to genetic and epigenetic changes. Promising results have been observed in preclinical models targeting these CSCs through the disruption of stemness pathways in combination with current treatment modalities. This has led to anti-CSC-based clinical trials in multiple stages of development. In this review, we discuss the role of CSCs and stemness pathways in cancer treatment and how they relate to clinical observations. Because CSCs and the stemness pathways governing them may explain the negative clinical outcomes observed during treatment, it is important for oncologists to understand how they contribute to cancer progression and how they may be targeted to improve patient outcomes.

Meta-analysis showing that early response to neoadjuvant chemotherapy predicts better survival among cervical cancer patients

This study was designed to identify the prognostic value of early response to neoadjuvant chemotherapy (NACT) for long-term survival of cervical cancer patients. We searched Pubmed and EMBASE for studies published through July 2016 on outcomes of cervical patients that received NACT. Eight studies involving 825 cervical cancer patients were ultimately included in our meta-analysis. We pooled the hazard ratios (HR) according to random-effects models and used funnel plots with Egger's and Begg's tests to explore potential publication bias. The HR between early response and 1-year overall survival (OS) was 3.60 (95% CI 1.93–6.72; I² = 0). Similar results were found in the analysis of 3-year OS (HR 3.34; 95% CI 2.28–4.90; I² = 0) and 5-year OS (HR 3.44; 95% CI 2.40–4.94; I² = 0). Sensitivity analysis showed that all of the pooled results were robust, and all logHRs had confidence limits > 0. Our findings indicate that early response is associated with long-term survival, and responders achieved a higher survival rate than non-responders.