Stratified phase II trial to establish the usefulness of the collagen gel droplet embedded culture-drug sensitivity test (CD-DST) for advanced gastric cancer

CircRNA: A new class of targets for gastric cancer drug resistance therapy

Gastric cancer (GC) is one of the most common malignancies worldwide. Patients with advanced GC need palliative care to ensure survival. This includes the use of chemotherapy agents, such as cisplatin, 5-fluorouracil, oxaliplatin, paclitaxel, and pemetrexed, as well as targeted agents. However, the emergence of drug resistance evidence in poor patient outcomes and poor prognosis is a motivation to determine the specific mechanism of drug resistance. Interestingly, circular RNAs (circRNAs) play an important part in the carcinogenesis and progression of GC and are involved in GC drug resistance. This review systematically summarizes the functions and mechanisms of circRNAs underlying GC drug resistance, especially chemoresistance. It also emphasizes that circRNAs can serve as promising targets for improving drug resistance and therapeutic efficacy.

Knockdown of ENTPD5 inhibits tumor metastasis and growth via regulating the GRP78/p-eIF-2α/CHOP pathway in serous ovarian cancer

Background

Dysregulation of Ectonucleoside Triphospahate Diphosphohydrolase 5 (ENTPD5) in tumors might be associated with tumor progression, while the role of ENTPD5 in the growth and metastasis of serous ovarian cancer (SOC) is still unclear.

Methods

ENTPD5 expression patterns in ovarian cancer tissues were analyzed by qRT-PCR and immunohistochemistry assay (IHC). Two SOC cell lines, SKOV3 and OVCAR8, were stably transfected with lentivirus to build knockdown and overexpression cell lines. Clone formation assay, collagen gel droplet culture technology, wound healing assay and flow cytometry were used to assess the migration and growth traits of SOC cells. Expression levels of ENTPD5, glucose regulated protein 78 (GRP78), eukaryotic translation initiation factor 2 alpha (eIF-2α), phosphorylated -eIF-2α and, C/EBP homologous protein (CHOP) in SOC cells were detected by Western blot.

Results

Compared to fallopian tube tissues, the expression of ENTPD5 was significantly higher in tumor tissues obtained from SOC patients, and positively correlated with clinical stage and metastasis. ENTPD5 knockdown robustly inhibited cell proliferation, migration, whereas ENTPD5 overexpression elicited the opposite effect on SOC cells. ENTPD5 knockdown arrested cell cycle in G0/G1 phase and increased apoptosis. Importantly, ENTPD5 knockdown was associated with significantly decreased protein levels for GRP78, CHOP, and p-eIF-2α, suggesting possible involvement of ENTPD5 in endoplasmic reticulum stress (ERS).

Conclusions

Our study demonstrates that ENTPD5 knockdown inhibited SOC cell proliferation, migration and restrained the activation of the GRP78/p-eIF-2α/CHOP pathway, which provides a potentially effective therapeutic target for the treatment of SOC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13048-022-00996-0.

Benefits of functional assays in personalized cancer medicine: more than just a proof-of-concept

As complex and heterogeneous diseases, cancers require a more tailored therapeutic management than most pathologies. Recent advances in anticancer drug development, including the immuno-oncology revolution, have been too often plagued by unsatisfying patient response rates and survivals. In reaction to this, cancer care has fully transitioned to the “personalized medicine” concept. Numerous tools are now available tools to better adapt treatments to the profile of each patient. They encompass a large array of diagnostic assays, based on biomarkers relevant to targetable molecular pathways. As a subfamily of such so-called companion diagnostics, chemosensitivity and resistance assays represent an attractive, yet insufficiently understood, approach to individualize treatments. They rely on the assessment of a composite biomarker, the ex vivo functional response of cancer cells to drugs, to predict a patient's outcome. Systemic treatments, such as chemotherapies, as well as targeted treatments, whose efficacy cannot be fully predicted yet by other diagnostic tests, may be assessed through these means. The results can provide helpful information to assist clinicians in their decision-making process. We explore here the most advanced functional assays across oncology indications, with an emphasis on tests already displaying a convincing clinical demonstration. We then recapitulate the main technical obstacles faced by researchers and clinicians to produce more accurate, and thus more predictive, models and the recent advances that have been developed to circumvent them. Finally, we summarize the regulatory and quality frameworks surrounding functional assays to ensure their safe and performant clinical implementation. Functional assays are valuable in vitro diagnostic tools that already stand beyond the “proof-of-concept” stage. Clinical studies show they have a major role to play by themselves but also in conjunction with molecular diagnostics. They now need a final lift to fully integrate the common armament used against cancers, and thus make their way into the clinical routine.

Yes associated protein 1 promotes resistance to 5-fluorouracil in gastric cancer by regulating GLUT3-dependent glycometabolism reprogramming of tumor-associated macrophages

The antimetabolite 5-fluorouracil (5-FU) is a widely used chemotherapy regimen for the treatment of gastric cancer (GC). However, resistance to 5-FU remains a major drawback in the clinical use. The treatments of anti-tumor chemo-agents recruit tumor associated macrophages (TAMs) which are highly implicated in the chemoresistance development, but the underlying molecular mechanism is unclear. Here, we demonstrate that YAP1 is overexpressed in resistant GC tissues compared to sensitive GC tissues. Further, IL-3 secreted by YAP1-overexpressed GC could skew macrophage polarization to M2-like phenotype and inducing GLUT3-depended glycolysis program. Meanwhile, polarized M2 macrophages enhance 5-FU resistance in tumor cells by secreting CCL8 and activating phosphorylation of JAK1/STAT3 signaling pathway.

Evaluating the effectiveness of chemotherapy for thymic epithelial tumors using the CD-DST method

BACKGROUND

Thymic epithelial tumors (TET) are frequently eligible for curative-intent surgical resection. For locally advanced TETs, chemotherapy has been used to both reduce the tumor burden and achieve prolonged disease control. However, effective therapy for this disease largely remains to be determined. Here, we report the chemosensitivity of 100 patients with TETs determined by the collagen gel droplet embedded culture-drug sensitivity test (CD-DST).

METHODS

A total of 100 patients with TETs underwent surgical resection. The efficacy of antitumor agents on TET cells was tested by CD-DST.

RESULTS

Thymic epithelial tumors were pathologically confirmed after surgery: two cases were type A thymoma, 17 were type AB, 12 were type B1, 44 were type B2, 12 were type B3, and there were 13 cases with thymic carcinoma. A total of 36% patients with TETs were sensitive to different types of chemotherapeutic agents. There was no significant differences in age, histological type, clinical staging, or association with autoimmune diseases between sensitive and nonsensitive cases. Type B1 and B2 thymoma were relatively more sensitive to chemotherapeutic agents (6/12 and 18/44, respectively), while sensitivity of type B3 cases to chemotherapeutic agents was much lower (only 2/12). Cases with type A thymoma were not sensitive to any antitumor drugs. Among 11 chemotherapeutic agents tested in our study, the sensitivity of TETs to EPI was the highest (16%). No patients with thymoma were sensitive to Alimta (Pemetrexed).

CONCLUSIONS

Our work illuminates the effectiveness of chemotherapy for TETs and provides important clues for choosing antitumor drugs with relatively high drug sensitivity to TETs in advance.

Collagen gel droplet-embedded culture drug sensitivity test (CD-DST) predicts the effect of adjuvant chemotherapy on pancreatic cancer

PURPOSE

We evaluated the clinical effectiveness of collagen gel droplet-embedded culture drug sensitivity tests (CD-DSTs) in predicting the efficacy of adjuvant chemo-therapeutic treatments for pancreatic cancer (PC).

METHODS

The clinicopathological characteristics and prognoses of 22 PC patients who underwent CD-DST after pancreatectomy at Tohoku University between 2012 and 2016 were analyzed retrospectively. Eligibility criteria were resectable or borderline resectable PC, successful evaluation for 5-fluorouracil sensitivity by CD-DST, treatment with S-1 adjuvant chemotherapy, and no preoperative chemotherapy.

RESULTS

The rate of successful evaluation by CD-DST was 52.3% in PC. The optimal T/C ratio, defined as the ratio of the number of cancer cells in the treatment group (T) to that in the control group (C), for 5-fluorouracil was 85% using receiver operating characteristic curve analysis. The sensitive group (T/C ratio < 85%; n = 11) had a better recurrence-free survival rate than the resistant group (T/C ratio ≥ 85%; n = 11; P = 0.029). A Cox proportional hazards regression model demonstrated that sensitivity to 5-fluorouracil was an independent predictor of recurrence on multivariate analysis (hazard ratio 3.28; 95.0% CI 1.20-9.84; P = 0.020).

CONCLUSIONS

CD-DSTs helped to predict PC recurrence after S-1 adjuvant chemotherapy.

Vacquinol‑1 induces apoptosis in hepatocellular carcinoma cell

Vacquinol‑1 (Vacq), a quinolone derivative, has recently been reported to display potent antitumor effects in glioblastomas by inducing cellular massive vacuolization and cell death. However, whether Vacq induces cytotoxicities in other types of cancers, and the potential underlying mechanism, remain to be investigated. In the present study, it was revealed that Vacq suppressed cell growth and colony formation in the hepatocellular carcinoma (HCC) cell lines BEL7402 and Huh7. In addition, treatment with Vacq increased the number of early and late apoptotic cells as assessed by flow cytometry with fluorescein isothiocyanate‑conjugated Annexin V and propidium iodide double staining. Notably, the effect by Vacq in the tested cells could be inhibited by pretreatment with a broad specificity caspase inhibitor Z‑VAD‑FMK, suggesting that Vacq may induce apoptosis in HCC cells. Morphologically, exposure to Vacq resulted in nuclear fragmentation and the apoptotic body formation in HCC cells. Furthermore, Vacq treatment increased the cleavage of caspase‑3, caspase‑9 and poly(adenosine diphosphate‑ribose) polymerase‑1. Mechanistic analysis revealed that Vacq upregulated the expressions of pro‑apoptotic proteins [B‑cell lymphoma 2 (bcl‑2)‑associated X protein (Bax) and Bcl‑2‑like protein 11] and downregulated the pro‑survival protein, Bcl‑2, expression in HCC cells. Furthermore, Vacq induced Bax translocation. Of note, Vacq displayed inhibitory effects on patient‑derived HCC cells in two‑dimensional (2D) and three-dimensional (3D) cultures. Taken together, the data suggested that Vacq induced intrinsic apoptosis and may be utilized as an effective reagent for HCC treatment.

Clinical study on collagen gel droplet-embedded culture drug sensitivity test for multidrug combination chemotherapy and super selective intra-arterial infusion chemoradiotherapy in oral squamous cell carcinoma

Using trace three-dimensional culture, the collagen gel droplet-embedded culture drug sensitivity test (CD-DST) can be tested even in cases with a small number of cells, including oral squamous cell carcinoma (OSCC), and evaluation of the antitumor effect with a drug concentration close to the in vivo level is possible. The present report aimed to evaluate the utility of the CD-DST in the assessment of the in vitro efficacy of single-agent and multidrug combination chemotherapy for OSCC in comparison with the clinical response rates and to examine the possible clinical application of CD-DST for such cases. A total of 33 OSCC patients from whom 33 samples were obtained from January 2010 to September 2015 were included. CD-DST was performed, individually and in combination, on the three drugs [i.e., cisplatin (CDDP), 5-fluorouracil (5-FU), and docetaxel (DOC)] and on super selective intra-arterial infusion chemoradiotherapy (IACRT). The overall evaluable rate of the CD-DST in OSCC was 81.8% (27 of 33 cases) and the sensitivity to each anticancer drug was evaluated. The in vitro efficacy rates of IACRT, cisplatin + 5-fluorouracil, and docetaxel + cisplatin + 5-fluorouracil (TPF) confirmed the estimated clinical response rates. In 14 of 33 patients, the results of CD-DST were compared with clinical efficacy, which was judged based on measurable lesions on imaging. For TPF therapy, the sensitivity test of the IACRT had a positive predictive value of 90.9% (10 of 11 cases) and a negative predictive value of 100% (3 of 3 cases); the accuracy of the susceptibility test for the anticancer agents was 92.8% (13 of 14 cases). The CD-DST may be useful in selecting multidrug combination chemotherapy and IACRT for OSCC, however, accumulation of further clinical data is required in the future.

Collagen gel droplet-embedded culture drug sensitivity test for adjuvant chemotherapy after complete resection of non-small-cell lung cancer

PURPOSE

We conducted a prospective clinical study to individualize adjuvant chemotherapy after complete resection of non-small-cell lung cancer (NSCLC), based on the drug sensitivity test.

METHODS

Patients with resectable c-stage IB-IIIA NSCLC were registered between 2005 and 2010. We performed the collagen gel droplet-embedded culture drug sensitivity test (CD-DST) on a fresh surgical specimen to assess in vitro chemosensitivity and evaluated the prognostic outcome after adjuvant chemotherapy with carboplatin/paclitaxel based on the CD-DST.

RESULTS

Among 92 registered patients, 87 were eligible for inclusion in the analysis. The success rate of CD-DST was 86% and chemosensitivity to carboplatin and/or paclitaxel was evident in 57 (76%) of the 75 patients. Adjuvant chemotherapy was completed in 22 (73%) of 30 patients. The 5-year overall survival rates were 71, 73, and 75% for all, CD-DST success, and chemosensitive patients, respectively. The 5-year disease-free survival and overall survival rates of the chemosensitive patients who completed adjuvant chemotherapy using carboplatin/paclitaxel were 68 and 82%, respectively. The 5-year disease-free survival and overall survival rates of the patients with stage II-IIIA chemosensitive NSCLC were 58 and 75%, respectively. Comparative analyses of the chemosensitive and non-chemosensitive/CD-DST failure groups showed no significant survival difference.

CONCLUSIONS

CD-DST can be used to evaluate chemosensitivity after lung cancer surgery; however, its clinical efficacy for assessing individualized treatment remains uncertain.

Effect of wound fluid on chemotherapy sensitivity of T24 bladder cancer cells with different enhancer of zeste homolog 2 status

The present study investigated the effect of zeste homolog 2 (EZH2) and wound fluid (WF) on chemotherapy sensitivities of T24 bladder cancer cells by using a collagen gel droplet embedded culture-drug sensitivity test (CD-DST). T24 bladder cancer cells with different EZH2 expression levels were co-cultured with postoperative WF from patients with bladder cancer. The CD-DST was performed to detect the sensitivity of tumor cells to gemcitabine and cis-diamminedichloridoplatinum (II) (cisplatin, DDP). The survival rates of the bladder cancer cells were used to determine the drug's chemotherapeutic effect. EZH2 knockdown increased the sensitivity of the cells to gemcitabine and DDP, whereas EZH2 overexpression decreased the chemotherapeutic sensitivity. Except for the situation of EZH2 overexpression, co-culturing with WF induced significantly higher drug resistance in tumor cells. Overexpression of EZH2 and surgery-induced WF promoted the drug resistance of bladder cancer cells to the investigated chemotherapeutic agents, suggesting that more studies are needed to investigate the key mechanisms underlying the EZH2- and WF-induced reduction of susceptibility to chemotherapy drugs.

Impact of in vitro chemosensitivity test-guided platinum-based adjuvant chemotherapy on the surgical outcomes of patients with p-stage IIIA non-small cell lung cancer that underwent complete resection

The impact of in vitro chemosensitivity test-guided platinum-based adjuvant chemotherapy on the surgical outcomes of patients undergoing complete resection for locally advanced non-small cell lung cancer (NSCLC) has yet to be elucidated. In the present study, the utility of adjuvant chemotherapy based on the collagen gel droplet embedded culture drug sensitivity test (CD-DST) in patients with p (pathology)-stage IIIA NSCLC was retrospectively analyzed. A series of 39 patients that had received platinum-based adjuvant chemotherapy following complete resection between 2007 and 2012 were enrolled. Their surgical specimens were subjected to the CD-DST. The patients were subsequently classified into two groups on the basis of in vitro anti-cancer drug sensitivity data obtained using the CD-DST: The sensitive group (25 patients) were treated with regimens including one or two of the anti-cancer drug(s) that were indicated to be effective by the CD-DST, whereas the non-sensitive group (14 patients) were treated with chemotherapy regimens that did not include any CD-DST-selected anti-cancer drugs. There were no significant differences in the background characteristics of the two groups [including in respect of the pathological TN (tumor-lymph node) stage, tumor histology, epidermal growth factor receptor mutation status, the frequency of each chemotherapy regimen, and the number of administered cycles]. The 5-year disease-free survival (DFS) rate of the sensitive group was 32.3%, whereas that of the non-sensitive group was 14.3% (P=0.037). In contrast, no difference in overall survival (OS) was observed (P=0.76). Multivariate analysis revealed that adjuvant chemotherapy based on the CD-DST had a significant favorable effect on the DFS (P=0.01). Therefore, the present study has demonstrated that CD-DST data obtained from surgical specimens aid the selection of effective platinum-based adjuvant chemotherapy regimens for patients undergoing complete resection for p-stage IIIA NSCLC. The use of CD-DST-guided platinum-based regimens may have a beneficial impact on the DFS of such patients.

Collagen gel droplet-embedded culture drug sensitivity testing in hard palate cancer-predicted antitumor efficacy of cetuximab: A case report

In vitro anticancer drug sensitivity assessments have been performed for various types of cancer, and an association with clinical response has been observed. The collagen gel droplet-embedded culture drug sensitivity test (CD-DST) is an in vitro anticancer drug sensitivity test that has recently reported to be useful in oral squamous cell carcinoma (OSCC). CD-DST allows for the analysis of a smaller number of cells compared with other anticancer drug sensitivity tests. The present study reported a successful analysis of anticancer drug sensitivity using CD-DST on cervical lymph node tissue dissected following neoadjuvant chemotherapy from a 55-year-old man with advanced hard palate cancer. Tumor resection and bilateral neck dissection were performed following neoadjuvant chemotherapy (docetaxel + cisplatin + 5-fluorouracil; TPF) for hard palate cancer T2N2cM0. Local recurrence and cervical multiple skin metastasis occurred ~8 months after surgery, and the patient received six doses of cetuximab (C-mab) + cisplatin + 5-fluorouracil (C-mab + PF) administration, which is a type of molecular-targeted therapy. Following the use of the CD-DST method, the clinical response was noted as stable disease following execution of TPF and partial response following execution of C-mab + PF. In addition, low sensitivity by TPF and high sensitivity by C-mab + PF were reported. The CD-DST method reflected the clinical response for the patient, and the results of the current study indicate that CD-DST is a useful tool for selecting chemotherapeutic drugs for patients with OSCC.

The Collagen Gel Droplet-embedded Culture Drug Sensitivity Test in Relapsed Hepatoblastoma

There are few treatment options for patients with unresectable or refractory hepatoblastoma which has failed to respond to the standard treatment. The rarity of the disease and lack of experimental materials have hampered the development of new treatments. In this study, the collagen gel droplet-embedded culture drug sensitivity test was used to evaluate the effectiveness of the multikinase inhibitors sorafenib and sunitinib, and other drugs, in relapsed hepatoblastoma tumor tissues. Tumor samples from 6 patients with relapsed hepatoblastoma were tested for drug sensitivity by the collagen gel droplet-embedded culture drug sensitivity test; evaluable results were obtained from 5 of them. All samples were judged to be sensitive to sorafenib with a 50% growth inhibitory concentration (IC50) of 0.5 to 3.1 μg/mL. Sunitinib did not achieve IC50 in 2 of 3 samples within the tested concentration range based on clinically observed serum concentrations. In the drug combination assay using a hepatoblastoma cell line, sorafenib showed synergistic effects with SN-38, an active metabolite of irinotecan. Our results provide the basic science background warranting future clinical trials of a combination of sorafenib and irinotecan for relapsed or refractory hepatoblastoma.

Relationships of MMP-9, E-cadherin, and VEGF expression with clinicopathological features and response to chemosensitivity in gastric cancer

The matrix metalloproteinase-9, E-cadherin, and vascular endothelial growth factor play an important role in behavior of tumor cell growth, invasion, and metastasis. In this study, we investigated the relationships of matrix metalloproteinase-9, E-cadherin, and vascular endothelial growth factor expression with clinicopathological features and results of chemosensitivity tested by collagen gel droplet–embedded culture–drug sensitivity test in gastric cancer. Fresh specimens were used for collagen gel droplet–embedded culture–drug sensitivity test and paired fixed specimens were used for immunohistochemistry. Positive expression of matrix metalloproteinase-9 was associated with poorly differentiated carcinoma (p = 0.032), lymph node metastasis (p = 0.022), and tumor stage (p = 0.023). Negative expression of E-cadherin was associated with poorly differentiated carcinoma (p = 0.007), lymph node metastasis (p = 0.012), and tumor stage (p = 0.007). Positive expression of vascular endothelial growth factor was associated with tumor size (p = 0.040) and stage (p = 0.007). Collagen gel droplet–embedded culture–drug sensitivity test was successfully evaluated in 56 patients. Among them, 29 (51.7%) patients were resistant to TS-1 and 31 (55.3%) patients were resistant to L-OHP. The L-OHP resistance rate in vascular endothelial growth factor positive patients was significantly higher than that in negative patients (p = 0.031). The L-OHP resistance rate in E-cadherin negative patients was significantly higher than that in positive patients (p = 0.014). In conclusion, matrix metalloproteinase-9, E-cadherin, and vascular endothelial growth factor were involved in tumor invasion and metastasis. Positive expression of matrix metalloproteinase-9 and vascular endothelial growth factor and negative expression of E-cadherin were malignant markers for gastric cancer. Positive expression of vascular endothelial growth factor and negative expression of E-cadherin were associated with L-OHP resistance.

Influence of wound fluid on chemotherapy sensitivity in primary breast cancer cells

Objective

To investigate the effect of WF on chemotherapy sensitivities of primary breast cancer cells from breast cancer patients by using CD-DST.

Results

In general, the WF-treated cells showed remarkable increase in survival rates as compared to the control cells cultured without WF among different anticancer drug subgroups. This trend was generally observed in all the tumor cells from the premenopausal, postmenopausal, T2, N0, N1, luminal B, and TN patients.

Methods

The sensitivities of WF-treated primary breast cancer cells, from 21 patients who underwent a radical resection for breast cancer from September 2014 to July 2015, to anticancer drugs: EPI, CDDP, DOC, VNR, 5-FU+LV, and PAC, were obtained using CD-DST. The survival rates of the breast cancer cells were recorded and used to gauge the chemotherapeutic effect.

Conclusions

Surgery-induced WF promotes the drug resistance of primary breast cancer cells to chemotherapy, suggesting that surgery may have adverse effects on breast cancer patients. More studies are needed to investigate the key factors in WF that enhance the susceptibility to chemotherapy drugs.

Precision or Personalized Medicine for Cancer Chemotherapy: Is there a Role for Herbal Medicine

Although over 100 chemotherapeutic agents are currently available for the treatment of cancer patients, the overall long term clinical benefit is disappointing due to the lack of effectiveness or severe side effects from these agents. In order to improve the therapeutic outcome, a new approach called precision medicine or personalized medicine has been proposed and initiated by the U.S. National Institutes of Health. However, the limited availability of effective medications and the high cost are still the major barriers for many cancer patients. Thus alternative approaches such as herbal medicines could be a feasible and less costly option. Unfortunately, scientific evidence for the efficacy of a majority of herbal medicines is still lacking and their development to meet FDA approval or other regulatory agencies is a big challenge. However, herbal medicines may be able to play an important role in precision medicine or personalized medicine. This review will focus on the existing and future technologies that could speed the development of herbal products for treatment of resistant cancer in individual patients. Specifically, it will concentrate on reviewing the phenotypic (activity based) rather than genotypic (mechanism based) approach to develop herbal medicine useful for personalized cancer chemotherapy.

Exploratory phase II trial in a multicenter setting to evaluate the clinical value of a chemosensitivity test in patients with gastric cancer (JACCRO-GC 04, Kubota memorial trial)

BACKGROUND

Although postoperative adjuvant chemotherapy with S-1, an oral fluoropyrimidine, has become a standard of care for gastric cancer in Japan, nonresponders may suffer from the cost and adverse reactions without clinical benefit. This multicenter exploratory phase II trial was conducted to see whether a chemosensitivity test, the collagen gel droplet embedded culture drug sensitivity test (CD-DST), can adequately select patients for chemotherapy.

METHODS

The CD-DST using four different concentrations of 5-fluorouracil was conducted with resected specimens from preregistered patients who underwent gastrectomy with D2 or more extensive lymphadenectomy. Patients who were histopathologically confirmed to have stage II or greater disease without distant metastasis were eligible for final enrollment. All patients underwent protocol-specified adjuvant chemotherapy with S-1. Three-year relapse-free survival was compared between patients determined as sensitive by the CD-DST (responders) and those deemed insensitive (nonresponders). Appropriate cutoff values for in vitro growth inhibition were defined when the hazard ratio for relapse in responders and the log-rank P values were at their minimum.

RESULTS

Of the 311 patients enrolled, 14 were ineligible and 27 failed to start the protocol treatment. The CD-DST failed in 64 other patients, and survival analyses were conducted with the remaining 206 patients (39 stage II disease, 155 stage III disease, and 12 stage IV disease). The outcome of patients who were determined to be responders was significantly superior to that of nonresponders regardless of the 5-fluorouracil concentrations, although no differences in clinicopathologic characteristics were observed between the two groups, except for age.

CONCLUSIONS

The CD-DST identified those who benefit from adjuvant chemotherapy. It deserves further evaluation in the setting of a prospective randomized trial. ClinicalTrials.gov identifier: NCT00287755.

Drug sensitivity testing platforms for gastric cancer diagnostics

Gastric cancer diagnostics has traditionally been histomorphological and primarily the domain of surgical pathologists. Although there is an increasing usage of molecular and genomic techniques for clinical diagnostics, there is an emerging field of personalised drug sensitivity testing. In this review, we describe the various personalised drug sensitivity testing platforms and discuss the challenges facing clinical adoption of these assays for gastric cancer.

High Expression of Pyruvate Kinase M2 is Associated with Chemosensitivity to Epirubicin and 5-Fluorouracil in Breast Cancer

BACKGROUND

Pyruvate kinase M2 (PKM2) is the key enzyme in the Warburg effect, and it was recently reported to be involved in the metabolic pathways of chemotherapeutic drugs. However, the role of PKM2 in breast cancer and its influence in the sensitivity to front-line anticancer drugs remains unclear.

METHODS

In this study, we examined the correlation between the expression of PKM2 and the sensitivity of primary breast cancer cells to anticancer drugs. PKM2 expression was studied by immunohistochemistry using biopsy samples of 296 patients diagnosed with invasive breast carcinoma, and the collagen gel droplet embedded culture-drug sensitivity tests (CD-DST) was conducted to all the patients to detect in vitro chemosensitivity after surgery.

RESULTS

We found high PKM2 expression was significantly associated with in vitro chemosensitivity to epirubicin (EPI) (P=0.019) and 5-fluorouracil (5-Fu) (P=0.009) in breast cancer patients. Then we used a small group of neoadjuvant chemotherapy cases to confirm that the higher PKM2 expression, the better pathological response to therapy was obtained in patients treated with EPI-based or EPI plus 5-Fu chemotherapy regimens. Although univariate and multivariate analysis indicated that high PKM2 was a poor independent predictor of progression free survival (PFS) and overall survival (OS) in breast cancer, patients with PKM2 high expression who received EPI-based or EPI plus 5-Fu chemotherapy were found to have a longer PFS (P=0.003, P=0.013) and OS (P=0.003, P=0.004) than patients treated with non-EPI/5-Fu-based regimens, respectively.

CONCLUSIONS

Our findings confirmed the poor prognosis of high PKM2 expression in breast cancer patients and revealed the predictive value of high PKM2 in the therapeutic response to EPI and 5-Fu. Moreover, our results provide the guidance of individual treatment for breast cancer patients who are foreboded a poor prognosis by the presence of high PKM2 status.